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File: //opt/saltstack/salt/lib/python3.10/site-packages/salt/minion.py
"""
Routines to set up a minion
"""

import binascii
import collections
import contextlib
import copy
import errno
import functools
import gc
import logging
import multiprocessing
import os
import random
import signal
import stat
import sys
import threading
import time
import traceback
import types
import uuid
from collections import OrderedDict

import salt
import salt.beacons
import salt.channel.client
import salt.cli.daemons
import salt.client
import salt.crypt
import salt.defaults.events
import salt.defaults.exitcodes
import salt.engines
import salt.ext.tornado
import salt.ext.tornado.gen
import salt.ext.tornado.ioloop
import salt.loader
import salt.loader.lazy
import salt.payload
import salt.pillar
import salt.serializers.msgpack
import salt.syspaths
import salt.transport
import salt.utils.args
import salt.utils.atomicfile
import salt.utils.context
import salt.utils.data
import salt.utils.dictdiffer
import salt.utils.dictupdate
import salt.utils.error
import salt.utils.event
import salt.utils.extmods
import salt.utils.files
import salt.utils.jid
import salt.utils.minion
import salt.utils.minions
import salt.utils.network
import salt.utils.platform
import salt.utils.process
import salt.utils.schedule
import salt.utils.ssdp
import salt.utils.state
import salt.utils.user
import salt.utils.zeromq
from salt._compat import ipaddress
from salt.config import DEFAULT_MINION_OPTS
from salt.defaults import DEFAULT_TARGET_DELIM
from salt.exceptions import (
    CommandExecutionError,
    CommandNotFoundError,
    SaltClientError,
    SaltDaemonNotRunning,
    SaltException,
    SaltInvocationError,
    SaltMasterUnresolvableError,
    SaltReqTimeoutError,
    SaltSystemExit,
)
from salt.template import SLS_ENCODING
from salt.utils.ctx import RequestContext
from salt.utils.debug import enable_sigusr1_handler
from salt.utils.event import tagify
from salt.utils.network import parse_host_port
from salt.utils.process import ProcessManager, SignalHandlingProcess, default_signals
from salt.utils.zeromq import ZMQ_VERSION_INFO, zmq

try:
    import psutil

    HAS_PSUTIL = True
except ImportError:
    HAS_PSUTIL = False

try:
    import resource

    HAS_RESOURCE = True
except ImportError:
    HAS_RESOURCE = False

try:
    import salt.utils.win_functions

    HAS_WIN_FUNCTIONS = True
except ImportError:
    HAS_WIN_FUNCTIONS = False


log = logging.getLogger(__name__)


# Event used to abort an in-progress resolve_dns() retry loop. The minion
# signal handler sets this so that a SIGTERM arriving while the minion is
# stuck retrying master DNS resolution can shut the io_loop down promptly
# instead of waiting for ``retry_dns`` seconds * forever. See #69466.
_RESOLVE_DNS_ABORT = threading.Event()


def request_resolve_dns_abort():
    """
    Signal any in-progress resolve_dns() retry loop to abort on its next
    wakeup. Used by the minion shutdown path so SIGTERM is not blocked by
    a synchronous ``time.sleep`` inside the DNS retry loop.
    """
    _RESOLVE_DNS_ABORT.set()


def _interruptible_sleep(duration, abort_event, chunk=1.0):
    """
    Sleep up to ``duration`` seconds in ``chunk``-second slices, returning
    early if ``abort_event`` becomes set. Returns True if the event was
    observed set (i.e. the sleep was aborted), False otherwise.

    Using small chunks rather than ``abort_event.wait(duration)`` keeps
    behavior consistent across platforms where ``Event.wait`` may starve
    other threads sharing the GIL during very long timeouts.
    """
    if duration <= 0:
        return abort_event.is_set()
    deadline = time.monotonic() + duration
    while True:
        if abort_event.is_set():
            return True
        remaining = deadline - time.monotonic()
        if remaining <= 0:
            return abort_event.is_set()
        time.sleep(min(chunk, remaining))


# To set up a minion:
# 1. Read in the configuration
# 2. Generate the function mapping dict
# 3. Authenticate with the master
# 4. Store the AES key
# 5. Connect to the publisher
# 6. Handle publications


def resolve_dns(opts, fallback=True):
    """
    Resolves the master_ip and master_uri options
    """
    ret = {}
    check_dns = True
    if opts.get("file_client", "remote") == "local" and not opts.get(
        "use_master_when_local", False
    ):
        check_dns = False
    import salt.utils.network

    if check_dns is True:
        try:
            if opts["master"] == "":
                raise SaltSystemExit
            ret["master_ip"] = salt.utils.network.dns_check(
                opts["master"], int(opts["master_port"]), True, opts["ipv6"]
            )
        except SaltClientError:
            retry_dns_count = opts.get("retry_dns_count", None)
            if opts["retry_dns"]:
                # Clear any leftover abort from a previous resolve. The flag
                # is only meaningful for the duration of an active retry
                # loop; if it is already set when we enter we honor it on
                # the first iteration below.
                while True:
                    if retry_dns_count is not None:
                        if retry_dns_count == 0:
                            raise SaltMasterUnresolvableError
                        retry_dns_count -= 1
                    log.error(
                        "Master hostname: '%s' not found or not responsive. "
                        "Retrying in %s seconds",
                        opts["master"],
                        opts["retry_dns"],
                    )
                    aborted = _interruptible_sleep(
                        opts["retry_dns"], _RESOLVE_DNS_ABORT
                    )
                    if aborted:
                        log.warning(
                            "Master DNS retry loop aborted by shutdown "
                            "request before '%s' could be resolved.",
                            opts["master"],
                        )
                        raise SaltMasterUnresolvableError
                    try:
                        ret["master_ip"] = salt.utils.network.dns_check(
                            opts["master"], int(opts["master_port"]), True, opts["ipv6"]
                        )
                        break
                    except SaltClientError:
                        pass
            else:
                if fallback:
                    ret["master_ip"] = "127.0.0.1"
                else:
                    raise
        except SaltSystemExit:
            unknown_str = "unknown address"
            master = opts.get("master", unknown_str)
            if master == "":
                master = unknown_str
            if opts.get("__role") == "syndic":
                err = (
                    "Master address: '{}' could not be resolved. Invalid or"
                    " unresolveable address. Set 'syndic_master' value in minion"
                    " config.".format(master)
                )
            else:
                err = (
                    "Master address: '{}' could not be resolved. Invalid or"
                    " unresolveable address. Set 'master' value in minion config.".format(
                        master
                    )
                )
            log.error(err)
            raise SaltSystemExit(code=42, msg=err)
    else:
        ret["master_ip"] = "127.0.0.1"

    if "master_ip" in ret and "master_ip" in opts:
        if ret["master_ip"] != opts["master_ip"]:
            log.warning(
                "Master ip address changed from %s to %s",
                opts["master_ip"],
                ret["master_ip"],
            )
    if opts["source_interface_name"]:
        log.trace("Custom source interface required: %s", opts["source_interface_name"])
        interfaces = salt.utils.network.interfaces()
        log.trace("The following interfaces are available on this Minion:")
        log.trace(interfaces)
        if opts["source_interface_name"] in interfaces:
            if interfaces[opts["source_interface_name"]]["up"]:
                addrs = (
                    interfaces[opts["source_interface_name"]]["inet"]
                    if not opts["ipv6"]
                    else interfaces[opts["source_interface_name"]]["inet6"]
                )
                ret["source_ip"] = addrs[0]["address"]
                log.debug("Using %s as source IP address", ret["source_ip"])
            else:
                log.warning(
                    "The interface %s is down so it cannot be used as source to connect"
                    " to the Master",
                    opts["source_interface_name"],
                )
        else:
            log.warning(
                "%s is not a valid interface. Ignoring.", opts["source_interface_name"]
            )
    elif opts["source_address"]:
        ret["source_ip"] = salt.utils.network.dns_check(
            opts["source_address"], int(opts["source_ret_port"]), True, opts["ipv6"]
        )
        log.debug("Using %s as source IP address", ret["source_ip"])
    if opts["source_ret_port"]:
        ret["source_ret_port"] = int(opts["source_ret_port"])
        log.debug("Using %d as source port for the ret server", ret["source_ret_port"])
    if opts["source_publish_port"]:
        ret["source_publish_port"] = int(opts["source_publish_port"])
        log.debug(
            "Using %d as source port for the master pub", ret["source_publish_port"]
        )
    ret["master_uri"] = "tcp://{ip}:{port}".format(
        ip=ret["master_ip"], port=opts["master_port"]
    )
    log.debug("Master URI: %s", ret["master_uri"])

    return ret


def prep_ip_port(opts):
    """
    parse host:port values from opts['master'] and return valid:
        master: ip address or hostname as a string
        master_port: (optional) master returner port as integer

    e.g.:
      - master: 'localhost:1234' -> {'master': 'localhost', 'master_port': 1234}
      - master: '127.0.0.1:1234' -> {'master': '127.0.0.1', 'master_port' :1234}
      - master: '[::1]:1234' -> {'master': '::1', 'master_port': 1234}
      - master: 'fe80::a00:27ff:fedc:ba98' -> {'master': 'fe80::a00:27ff:fedc:ba98'}
    """
    ret = {}
    # Use given master IP if "ip_only" is set or if master_ip is an ipv6 address without
    # a port specified. The is_ipv6 check returns False if brackets are used in the IP
    # definition such as master: '[::1]:1234'.
    if opts["master_uri_format"] == "ip_only":
        ret["master"] = ipaddress.ip_address(opts["master"])
    else:
        try:
            host, port = parse_host_port(opts["master"])
        except ValueError as exc:
            raise SaltClientError(exc)
        ret = {"master": host}
        if port:
            ret.update({"master_port": port})

    return ret


def get_proc_dir(cachedir, **kwargs):
    """
    Given the cache directory, return the directory that process data is
    stored in, creating it if it doesn't exist.
    The following optional Keyword Arguments are handled:

    mode: which is anything os.makedir would accept as mode.

    uid: the uid to set, if not set, or it is None or -1 no changes are
         made. Same applies if the directory is already owned by this
         uid. Must be int. Works only on unix/unix like systems.

    gid: the gid to set, if not set, or it is None or -1 no changes are
         made. Same applies if the directory is already owned by this
         gid. Must be int. Works only on unix/unix like systems.
    """
    # pylint: disable=logging-fstring-interpolation
    fn_ = os.path.join(cachedir, "proc")
    mode = kwargs.pop("mode", None)

    if mode is None:
        mode = {}
    else:
        mode = {"mode": mode}

    if not os.path.isdir(fn_):
        # proc_dir is not present, create it with mode settings
        os.makedirs(fn_, **mode)

    d_stat = os.stat(fn_)

    # if mode is not an empty dict then we have an explicit
    # dir mode. So lets check if mode needs to be changed.
    if mode:
        mode_part = stat.S_IMODE(d_stat.st_mode)
        if mode_part != mode["mode"]:
            os.chmod(fn_, (d_stat.st_mode ^ mode_part) | mode["mode"])

    if hasattr(os, "chown"):
        # only on unix/unix like systems
        uid = kwargs.pop("uid", -1)
        gid = kwargs.pop("gid", -1)

        # pylint: disable=logging-fstring-interpolation
        # if uid and gid are both -1 then go ahead with
        # no changes at all
        if (d_stat.st_uid != uid or d_stat.st_gid != gid) and [
            i for i in (uid, gid) if i != -1
        ]:
            # pylint: disable=logging-fstring-interpolation
            os.chown(fn_, uid, gid)

    return fn_


def load_args_and_kwargs(func, args, data=None, ignore_invalid=False):
    """
    Detect the args and kwargs that need to be passed to a function call, and
    check them against what was passed.
    """
    argspec = salt.utils.args.get_function_argspec(func)
    _args = []
    _kwargs = {}
    invalid_kwargs = []

    for arg in args:
        if isinstance(arg, dict) and arg.get("__kwarg__", False) is True:
            # if the arg is a dict with __kwarg__ == True, then its a kwarg
            for key, val in arg.items():
                # Skip __kwarg__ when checking kwargs
                if key == "__kwarg__":
                    continue
                if argspec.keywords or key in argspec.args:
                    # Function supports **kwargs or is a positional argument to
                    # the function.
                    _kwargs[key] = val
                else:
                    # **kwargs not in argspec and parsed argument name not in
                    # list of positional arguments. This keyword argument is
                    # invalid.
                    invalid_kwargs.append(f"{key}={val}")
            continue

        else:
            string_kwarg = salt.utils.args.parse_input([arg], condition=False)[
                1
            ]  # pylint: disable=W0632
            if string_kwarg:
                if argspec.keywords or next(iter(string_kwarg.keys())) in argspec.args:
                    # Function supports **kwargs or is a positional argument to
                    # the function.
                    _kwargs.update(string_kwarg)
                else:
                    # **kwargs not in argspec and parsed argument name not in
                    # list of positional arguments. This keyword argument is
                    # invalid.
                    for key, val in string_kwarg.items():
                        invalid_kwargs.append(f"{key}={val}")
            else:
                _args.append(arg)

    if invalid_kwargs and not ignore_invalid:
        salt.utils.args.invalid_kwargs(invalid_kwargs)

    if argspec.keywords and isinstance(data, dict):
        # this function accepts **kwargs, pack in the publish data
        for key, val in data.items():
            _kwargs[f"__pub_{key}"] = val

    return _args, _kwargs


def eval_master_func(opts):
    """
    Evaluate master function if master type is 'func'
    and save it result in opts['master']
    """
    if "__master_func_evaluated" not in opts:
        # split module and function and try loading the module
        mod_fun = opts["master"]
        mod, fun = mod_fun.split(".")
        try:
            master_mod = salt.loader.raw_mod(opts, mod, fun)
            if not master_mod:
                raise KeyError
            # we take whatever the module returns as master address
            opts["master"] = master_mod[mod_fun]()
            # Check for valid types
            if not isinstance(opts["master"], ((str,), list)):
                raise TypeError
            opts["__master_func_evaluated"] = True
        except KeyError:
            log.error("Failed to load module %s", mod_fun)
            sys.exit(salt.defaults.exitcodes.EX_GENERIC)
        except TypeError:
            log.error("%s returned from %s is not a string", opts["master"], mod_fun)
            sys.exit(salt.defaults.exitcodes.EX_GENERIC)
        log.info("Evaluated master from module: %s", mod_fun)


def master_event(type, master=None):
    """
    Centralized master event function which will return event type based on event_map
    """
    event_map = {
        "connected": "__master_connected",
        "disconnected": "__master_disconnected",
        "failback": "__master_failback",
        "alive": "__master_alive",
    }

    if type == "alive" and master is not None:
        return f"{event_map.get(type)}_{master}"

    return event_map.get(type, None)


def service_name():
    """
    Return the proper service name based on platform
    """
    return "salt_minion" if "bsd" in sys.platform else "salt-minion"


class MinionBase:
    def __init__(self, opts):
        self.opts = opts
        self.beacons_leader = opts.get("beacons_leader", True)

    def gen_modules(self, initial_load=False, context=None):
        """
        Tell the minion to reload the execution modules

        CLI Example:

        .. code-block:: bash

            salt '*' sys.reload_modules
        """
        if context is None:
            context = {}
        if initial_load:
            self.opts["pillar"] = salt.pillar.get_pillar(
                self.opts,
                self.opts["grains"],
                self.opts["id"],
                self.opts["saltenv"],
                pillarenv=self.opts.get("pillarenv"),
            ).compile_pillar()

        self.utils = salt.loader.utils(self.opts, context=context)
        self.functions = salt.loader.minion_mods(
            self.opts, utils=self.utils, context=context
        )
        self.serializers = salt.loader.serializers(self.opts)
        self.returners = salt.loader.returners(
            self.opts, functions=self.functions, context=context
        )
        self.proxy = salt.loader.proxy(
            self.opts, functions=self.functions, returners=self.returners
        )
        # TODO: remove
        self.function_errors = {}  # Keep the funcs clean
        self.states = salt.loader.states(
            self.opts,
            functions=self.functions,
            utils=self.utils,
            serializers=self.serializers,
            context=context,
        )
        self.rend = salt.loader.render(
            self.opts, functions=self.functions, context=context
        )
        #        self.matcher = Matcher(self.opts, self.functions)
        self.matchers = salt.loader.matchers(self.opts)
        self.functions["sys.reload_modules"] = self.gen_modules
        self.executors = salt.loader.executors(
            self.opts, functions=self.functions, proxy=self.proxy, context=context
        )

    @staticmethod
    def process_schedule(minion, loop_interval):
        try:
            if hasattr(minion, "schedule"):
                minion.schedule.eval()
            else:
                log.error(
                    "Minion scheduler not initialized. Scheduled jobs will not be run."
                )
                return
            # Check if scheduler requires lower loop interval than
            # the loop_interval setting
            if minion.schedule.loop_interval < loop_interval:
                loop_interval = minion.schedule.loop_interval
                log.debug("Overriding loop_interval because of scheduled jobs.")
        except Exception as exc:  # pylint: disable=broad-except
            log.error("Exception %s occurred in scheduled job", exc)
        return loop_interval

    def process_beacons(self, functions):
        """
        Evaluate all of the configured beacons, grab the config again in case
        the pillar or grains changed
        """
        if "config.merge" in functions:
            b_conf = functions["config.merge"](
                "beacons", self.opts["beacons"], omit_opts=True
            )
            if b_conf:
                return self.beacons.process(
                    b_conf, self.opts["grains"]
                )  # pylint: disable=no-member
        return []

    @salt.ext.tornado.gen.coroutine
    def eval_master(self, opts, timeout=60, safe=True, failed=False, failback=False):
        """
        Evaluates and returns a tuple of the current master address and the pub_channel.

        In standard mode, just creates a pub_channel with the given master address.

        With master_type=func evaluates the current master address from the given
        module and then creates a pub_channel.

        With master_type=failover takes the list of masters and loops through them.
        The first one that allows the minion to create a pub_channel is then
        returned. If this function is called outside the minions initialization
        phase (for example from the minions main event-loop when a master connection
        loss was detected), 'failed' should be set to True. The current
        (possibly failed) master will then be removed from the list of masters.
        """
        # return early if we are not connecting to a master
        if opts["master_type"] == "disable":
            log.warning("Master is set to disable, skipping connection")
            self.connected = False
            raise salt.ext.tornado.gen.Return((None, None))

        # Run masters discovery over SSDP. This may modify the whole configuration,
        # depending of the networking and sets of masters.
        self._discover_masters()

        # check if master_type was altered from its default
        if opts["master_type"] != "str" and opts["__role"] != "syndic":
            # check for a valid keyword
            if opts["master_type"] == "func":
                eval_master_func(opts)

            # if failover or distributed is set, master has to be of type list
            elif opts["master_type"] in ("failover", "distributed"):
                if isinstance(opts["master"], list):
                    log.info(
                        "Got list of available master addresses: %s", opts["master"]
                    )

                    if opts["master_type"] == "distributed":
                        master_len = len(opts["master"])
                        if master_len > 1:
                            secondary_masters = opts["master"][1:]
                            master_idx = binascii.crc32(opts["id"]) % master_len
                            try:
                                preferred_masters = opts["master"]
                                preferred_masters[0] = opts["master"][master_idx]
                                preferred_masters[1:] = [
                                    m
                                    for m in opts["master"]
                                    if m != preferred_masters[0]
                                ]
                                opts["master"] = preferred_masters
                                log.info(
                                    "Distributed to the master at '%s'.",
                                    opts["master"][0],
                                )
                            except (KeyError, AttributeError, TypeError):
                                log.warning(
                                    "Failed to distribute to a specific master."
                                )
                        else:
                            log.warning(
                                "master_type = distributed needs more than 1 master."
                            )

                    if opts["master_shuffle"]:
                        log.warning(
                            "Use of 'master_shuffle' detected. 'master_shuffle' is"
                            " deprecated in favor of 'random_master'. Please update"
                            " your minion config file."
                        )
                        opts["random_master"] = opts["master_shuffle"]

                    opts["auth_tries"] = 0
                    if (
                        opts["master_failback"]
                        and opts["master_failback_interval"] == 0
                    ):
                        opts["master_failback_interval"] = opts["master_alive_interval"]
                # if opts['master'] is a str and we have never created opts['master_list']
                elif isinstance(opts["master"], str) and ("master_list" not in opts):
                    # We have a string, but a list was what was intended. Convert.
                    # See issue 23611 for details
                    opts["master"] = [opts["master"]]
                elif opts["__role"] == "syndic":
                    log.info("Syndic setting master_syndic to '%s'", opts["master"])

                # if failed=True, the minion was previously connected
                # we're probably called from the minions main-event-loop
                # because a master connection loss was detected. remove
                # the possibly failed master from the list of masters.
                elif failed:
                    if failback:
                        # failback list of masters to original config
                        opts["master"] = opts["master_list"]
                    else:
                        log.info(
                            "Moving possibly failed master %s to the end of "
                            "the list of masters",
                            opts["master"],
                        )
                        if opts["master"] in opts["local_masters"]:
                            # create new list of master with the possibly failed
                            # one moved to the end
                            failed_master = opts["master"]
                            opts["master"] = [
                                x for x in opts["local_masters"] if opts["master"] != x
                            ]
                            opts["master"].append(failed_master)
                        else:
                            opts["master"] = opts["master_list"]
                else:
                    log.error(
                        "master_type set to 'failover' but 'master' is not of type list"
                        " but of type %s",
                        type(opts["master"]),
                    )
                    sys.exit(salt.defaults.exitcodes.EX_GENERIC)
                # If failover is set, minion have to failover on DNS errors instead of retry DNS resolve.
                # See issue 21082 for details
                if opts["retry_dns"] and opts["master_type"] == "failover":
                    log.critical(
                        "'master_type' set to 'failover' but 'retry_dns' is not 0."
                        " Setting 'retry_dns' to 0 to failover to the next master on"
                        " DNS errors."
                    )
                    opts["retry_dns"] = 0
            else:
                log.error(
                    "Invalid keyword '%s' for variable 'master_type'",
                    opts["master_type"],
                )
                sys.exit(salt.defaults.exitcodes.EX_GENERIC)

        # FIXME: if SMinion don't define io_loop, it can't switch master see #29088
        # Specify kwargs for the channel factory so that SMinion doesn't need to define an io_loop
        # (The channel factories will set a default if the kwarg isn't passed)
        factory_kwargs = {"timeout": timeout, "safe": safe}
        if getattr(self, "io_loop", None):
            factory_kwargs["io_loop"] = self.io_loop  # pylint: disable=no-member

        tries = opts.get("master_tries", 1)
        attempts = 0

        # if we have a list of masters, loop through them and be
        # happy with the first one that allows us to connect
        if isinstance(opts["master"], list):
            conn = False
            last_exc = None
            opts["master_uri_list"] = []
            opts["local_masters"] = copy.copy(opts["master"])

            # shuffle the masters and then loop through them
            if opts["random_master"]:
                # master_failback is only used when master_type is set to failover
                if opts["master_type"] == "failover" and opts["master_failback"]:
                    secondary_masters = opts["local_masters"][1:]
                    random.shuffle(secondary_masters)
                    opts["local_masters"][1:] = secondary_masters
                else:
                    random.shuffle(opts["local_masters"])

            # This sits outside of the connection loop below because it needs to set
            # up a list of master URIs regardless of which masters are available
            # to connect _to_. This is primarily used for masterless mode, when
            # we need a list of master URIs to fire calls back to.
            for master in opts["local_masters"]:
                opts["master"] = master
                opts.update(prep_ip_port(opts))
                if opts["master_type"] == "failover":
                    try:
                        opts["master_uri_list"].append(
                            resolve_dns(opts, False)["master_uri"]
                        )
                    except SaltClientError:
                        continue
                else:
                    opts["master_uri_list"].append(resolve_dns(opts)["master_uri"])

            if not opts["master_uri_list"]:
                msg = "No master could be resolved"
                log.error(msg)
                raise SaltClientError(msg)

            pub_channel = None
            while True:
                if attempts != 0:
                    # Give up a little time between connection attempts
                    # to allow the IOLoop to run any other scheduled tasks.
                    yield salt.ext.tornado.gen.sleep(opts["acceptance_wait_time"])
                attempts += 1
                if tries > 0:
                    log.debug("Connecting to master. Attempt %s of %s", attempts, tries)
                else:
                    log.debug(
                        "Connecting to master. Attempt %s (infinite attempts)", attempts
                    )
                for master in opts["local_masters"]:
                    opts["master"] = master
                    opts.update(prep_ip_port(opts))
                    if opts["master_type"] == "failover":
                        try:
                            opts.update(resolve_dns(opts, False))
                        except SaltClientError:
                            continue
                    else:
                        opts.update(resolve_dns(opts))

                    # on first run, update self.opts with the whole master list
                    # to enable a minion to re-use old masters if they get fixed
                    if "master_list" not in opts:
                        opts["master_list"] = copy.copy(opts["local_masters"])

                    self.opts = opts

                    pub_channel = salt.channel.client.AsyncPubChannel.factory(
                        opts, **factory_kwargs
                    )
                    try:
                        yield pub_channel.connect()
                        conn = True
                        # If we reached here, we are connected. We set pub_channel to None
                        # so that the finally block doesn't close it, but we keep a reference
                        # in the returnable variable.
                        ret_pub_channel = pub_channel
                        pub_channel = None
                        break
                    except SaltClientError as exc:
                        last_exc = exc
                        if exc.strerror.startswith("Could not access"):
                            log.info(
                                "Failed to initiate connection with Master %s: check"
                                " ownership/permissions. Error message: %s",
                                opts["master"],
                                exc,
                            )
                        else:
                            log.info(
                                "Master %s could not be reached, trying next master (if"
                                " any)",
                                opts["master"],
                            )
                        continue
                    finally:
                        if pub_channel:
                            pub_channel.close()

                if conn:
                    pub_channel = ret_pub_channel

                if not conn:
                    if attempts == tries:
                        # Exhausted all attempts. Return exception.
                        self.connected = False
                        self.opts["master"] = copy.copy(self.opts["local_masters"])
                        log.error(
                            "No master could be reached or all masters "
                            "denied the minion's connection attempt."
                        )
                        # If the code reaches this point, 'last_exc'
                        # should already be set.
                        raise last_exc  # pylint: disable=E0702
                else:
                    self.tok = pub_channel.auth.gen_token(b"salt")
                    self.connected = True
                    raise salt.ext.tornado.gen.Return((opts["master"], pub_channel))

        # single master sign in
        else:
            if opts["random_master"]:
                log.warning(
                    "random_master is True but there is only one master specified."
                    " Ignoring."
                )
            pub_channel = None
            while True:
                if attempts != 0:
                    # Give up a little time between connection attempts
                    # to allow the IOLoop to run any other scheduled tasks.
                    yield salt.ext.tornado.gen.sleep(opts["acceptance_wait_time"])
                attempts += 1
                if tries > 0:
                    log.debug("Connecting to master. Attempt %s of %s", attempts, tries)
                else:
                    log.debug(
                        "Connecting to master. Attempt %s (infinite attempts)", attempts
                    )
                opts.update(prep_ip_port(opts))
                opts.update(resolve_dns(opts))
                try:
                    if self.opts["transport"] == "detect":
                        self.opts["detect_mode"] = True
                        for trans in salt.transport.TRANSPORTS:
                            if trans == "zeromq" and not zmq:
                                continue
                            self.opts["transport"] = trans
                            pub_channel = salt.channel.client.AsyncPubChannel.factory(
                                self.opts, **factory_kwargs
                            )
                            yield pub_channel.connect()
                            if not pub_channel.auth.authenticated:
                                continue
                            del self.opts["detect_mode"]
                            break
                    else:
                        pub_channel = salt.channel.client.AsyncPubChannel.factory(
                            self.opts, **factory_kwargs
                        )
                        yield pub_channel.connect()
                    self.tok = pub_channel.auth.gen_token(b"salt")
                    self.connected = True
                    raise salt.ext.tornado.gen.Return((opts["master"], pub_channel))
                except SaltClientError:
                    if pub_channel:
                        pub_channel.close()
                    if attempts == tries:
                        # Exhausted all attempts. Return exception.
                        self.connected = False
                        raise

    def _discover_masters(self):
        """
        Discover master(s) and decide where to connect, if SSDP is around.
        This modifies the configuration on the fly.
        :return:
        """
        if (
            self.opts["master"] == DEFAULT_MINION_OPTS["master"]
            and self.opts["discovery"] is not False
        ):
            master_discovery_client = salt.utils.ssdp.SSDPDiscoveryClient()
            masters = {}
            for att in range(self.opts["discovery"].get("attempts", 3)):
                try:
                    att += 1
                    log.info("Attempting %s time(s) to discover masters", att)
                    masters.update(master_discovery_client.discover())
                    if not masters:
                        time.sleep(self.opts["discovery"].get("pause", 5))
                    else:
                        break
                except Exception as err:  # pylint: disable=broad-except
                    log.error("SSDP discovery failure: %s", err)
                    break

            if masters:
                policy = self.opts.get("discovery", {}).get("match", "any")
                if policy not in ["any", "all"]:
                    log.error(
                        'SSDP configuration matcher failure: unknown value "%s". '
                        'Should be "any" or "all"',
                        policy,
                    )
                else:
                    mapping = self.opts["discovery"].get("mapping", {})
                    for addr, mappings in masters.items():
                        for proto_data in mappings:
                            cnt = len(
                                [
                                    key
                                    for key, value in mapping.items()
                                    if proto_data.get("mapping", {}).get(key) == value
                                ]
                            )
                            if policy == "any" and bool(cnt) or cnt == len(mapping):
                                self.opts["master"] = proto_data["master"]
                                return

    def _return_retry_timer(self, max=False):
        """
        Based on the minion configuration, either return a randomized timer or
        just return the value of the return_retry_timer.
        """
        msg = "Minion return retry timer set to %s seconds"
        if self.opts.get("return_retry_timer_max"):
            if max:
                return self.opts["return_retry_timer_max"]
            try:
                random_retry = random.randint(
                    self.opts["return_retry_timer"], self.opts["return_retry_timer_max"]
                )
                retry_msg = msg % random_retry
                log.debug("%s (randomized)", msg % random_retry)
                return random_retry
            except ValueError:
                # Catch wiseguys using negative integers here
                log.error(
                    "Invalid value (return_retry_timer: %s or "
                    "return_retry_timer_max: %s). Both must be positive "
                    "integers.",
                    self.opts["return_retry_timer"],
                    self.opts["return_retry_timer_max"],
                )
                log.debug(msg, DEFAULT_MINION_OPTS["return_retry_timer"])
                return DEFAULT_MINION_OPTS["return_retry_timer"]
        else:
            log.debug(msg, self.opts.get("return_retry_timer"))
            return self.opts.get("return_retry_timer")


class SMinion(MinionBase):
    """
    Create an object that has loaded all of the minion module functions,
    grains, modules, returners etc.  The SMinion allows developers to
    generate all of the salt minion functions and present them with these
    functions for general use.
    """

    def __init__(self, opts, context=None):
        # Late setup of the opts grains, so we can log from the grains module
        import salt.loader

        opts["grains"] = salt.loader.grains(opts)
        super().__init__(opts)

        # Clean out the proc directory (default /var/cache/salt/minion/proc)
        if self.opts.get("file_client", "remote") == "remote" or self.opts.get(
            "use_master_when_local", False
        ):
            io_loop = salt.ext.tornado.ioloop.IOLoop.current()

            @salt.ext.tornado.gen.coroutine
            def eval_master():
                """
                Wrap eval master in order to close the returned publish channel.
                """
                master, pub_channel = yield self.eval_master(self.opts, failed=True)
                pub_channel.close()

            io_loop.run_sync(
                lambda: eval_master()  # pylint: disable=unnecessary-lambda
            )
        self.gen_modules(initial_load=True, context=context)

        # If configured, cache pillar data on the minion
        if self.opts["file_client"] == "remote" and self.opts.get(
            "minion_pillar_cache", False
        ):
            import salt.utils.yaml

            pdir = os.path.join(self.opts["cachedir"], "pillar")
            if not os.path.isdir(pdir):
                os.makedirs(pdir, 0o700)
            ptop = os.path.join(pdir, "top.sls")
            if self.opts["saltenv"] is not None:
                penv = self.opts["saltenv"]
            else:
                penv = "base"
            cache_top = {penv: {self.opts["id"]: ["cache"]}}
            with salt.utils.files.fopen(ptop, "wb") as fp_:
                salt.utils.yaml.safe_dump(cache_top, fp_, encoding=SLS_ENCODING)
                os.chmod(ptop, 0o600)
            cache_sls = os.path.join(pdir, "cache.sls")
            with salt.utils.files.fopen(cache_sls, "wb") as fp_:
                salt.utils.yaml.safe_dump(
                    self.opts["pillar"], fp_, encoding=SLS_ENCODING
                )
                os.chmod(cache_sls, 0o600)


class MasterMinion:
    """
    Create a fully loaded minion function object for generic use on the
    master. What makes this class different is that the pillar is
    omitted, otherwise everything else is loaded cleanly.
    """

    def __init__(
        self,
        opts,
        returners=True,
        states=True,
        rend=True,
        matcher=True,
        whitelist=None,
        ignore_config_errors=True,
    ):
        self.executors = None
        self.matchers = None
        self.opts = salt.config.mminion_config(
            opts["conf_file"], opts, ignore_config_errors=ignore_config_errors
        )
        self.whitelist = whitelist
        self.mk_returners = returners
        self.mk_states = states

        self.mk_rend = rend
        self.mk_matcher = matcher
        self.returners = None
        self.functions = None
        self.utils = None
        self.proxy = None
        self.gen_modules(initial_load=True)

    def destroy(self):
        """
        Destroy the MasterMinion object
        """
        if self.returners is not None:
            # Some returners have a destroy method
            for returner in self.returners:
                try:
                    func = self.returners[returner]
                    if hasattr(func, "destroy"):
                        func.destroy()
                except Exception:  # pylint: disable=broad-except
                    pass
            if hasattr(self.returners, "destroy"):
                self.returners.destroy()
            self.returners = {}
        if self.functions is not None and hasattr(self.functions, "destroy"):
            self.functions.destroy()
        self.functions = {}
        if self.utils is not None and hasattr(self.utils, "destroy"):
            self.utils.destroy()
        self.utils = {}
        if hasattr(self, "states") and self.states is not None:
            if hasattr(self.states, "destroy"):
                self.states.destroy()
            self.states = {}
        if hasattr(self, "rend") and self.rend is not None:
            if hasattr(self.rend, "destroy"):
                self.rend.destroy()
            self.rend = {}
        if hasattr(self, "matchers") and self.matchers is not None:
            if hasattr(self.matchers, "destroy"):
                self.matchers.destroy()
            self.matchers = {}
        if hasattr(self, "executors") and self.executors is not None:
            if hasattr(self.executors, "destroy"):
                self.executors.destroy()
            self.executors = {}
        if hasattr(self, "proxy") and self.proxy is not None:
            if hasattr(self.proxy, "destroy"):
                self.proxy.destroy()
            self.proxy = {}
        if hasattr(self, "serializers") and self.serializers is not None:
            if hasattr(self.serializers, "destroy"):
                self.serializers.destroy()
            self.serializers = {}
        if self.opts and "grains" in self.opts:
            if hasattr(self.opts["grains"], "destroy"):
                self.opts["grains"].destroy()
            self.opts["grains"] = {}

    def __enter__(self):
        return self

    def __exit__(self, *args):
        self.destroy()

    def gen_modules(self, initial_load=False):
        """
        Tell the minion to reload the execution modules

        CLI Example:

        .. code-block:: bash

            salt '*' sys.reload_modules
        """
        self.utils = salt.loader.utils(self.opts)
        self.functions = salt.loader.minion_mods(
            self.opts,
            utils=self.utils,
            whitelist=self.whitelist,
            initial_load=initial_load,
        )
        self.serializers = salt.loader.serializers(self.opts)
        if self.mk_returners:
            self.returners = salt.loader.returners(self.opts, self.functions)
        if self.mk_states:
            self.states = salt.loader.states(
                self.opts, self.functions, self.utils, self.serializers
            )
        if self.mk_rend:
            self.rend = salt.loader.render(self.opts, self.functions)
        if self.mk_matcher:
            self.matchers = salt.loader.matchers(self.opts)
        self.functions["sys.reload_modules"] = self.gen_modules


class MinionManager(MinionBase):
    """
    Create a multi minion interface, this creates as many minions as are
    defined in the master option and binds each minion object to a respective
    master.
    """

    def __init__(self, opts):
        super().__init__(opts)
        self.auth_wait = self.opts["acceptance_wait_time"]
        self.max_auth_wait = self.opts["acceptance_wait_time_max"]
        self.minions = []
        self.jid_queue = []

        self.io_loop = salt.ext.tornado.ioloop.IOLoop.current()
        self.process_manager = ProcessManager(name="MultiMinionProcessManager")
        self.io_loop.spawn_callback(
            self.process_manager.run, **{"asynchronous": True}
        )  # Tornado backward compat
        self.event_publisher = None
        self.event = None

    # pylint: disable=W1701
    def __del__(self):
        self.destroy()

    # pylint: enable=W1701

    def _bind(self):
        # start up the event publisher, so we can see events during startup
        self.event_publisher = salt.utils.event.AsyncEventPublisher(
            self.opts,
            io_loop=self.io_loop,
        )
        self.event = salt.utils.event.get_event(
            "minion", opts=self.opts, io_loop=self.io_loop
        )
        self.event.subscribe("")
        self.event.set_event_handler(self.handle_event)

    @salt.ext.tornado.gen.coroutine
    def handle_event(self, package):
        try:
            yield [_.handle_event(package) for _ in self.minions]
        except Exception as exc:  # pylint: disable=broad-except
            log.error("Error dispatching event. %s", exc)

    def destroy(self):
        """
        Tear down the MinionManager
        """
        if hasattr(self, "process_manager") and self.process_manager is not None:
            self.process_manager.stop_restarting()
            self.process_manager.kill_children()
        if hasattr(self, "minions"):
            for minion in self.minions:
                if hasattr(minion, "destroy"):
                    minion.destroy()
            self.minions = []

    def _create_minion_object(
        self,
        opts,
        timeout,
        safe,
        io_loop=None,
        loaded_base_name=None,
        jid_queue=None,
        load_grains=True,
    ):
        """
        Helper function to return the correct type of object
        """
        return Minion(
            opts,
            timeout,
            safe,
            io_loop=io_loop,
            loaded_base_name=loaded_base_name,
            jid_queue=jid_queue,
            load_grains=load_grains,
        )

    def _check_minions(self):
        """
        Check the size of self.minions and raise an error if it's empty
        """
        if not self.minions:
            log.error("Minion unable to successfully connect to a Salt Master.")

    def _spawn_minions(self, timeout=60):
        """
        Spawn all the coroutines which will sign in to masters
        """
        masters = self.opts["master"]
        if (self.opts["master_type"] in ("failover", "distributed")) or not isinstance(
            self.opts["master"], list
        ):
            masters = [masters]

        beacons_leader = True
        for master in masters:
            s_opts = copy.deepcopy(self.opts)
            s_opts["master"] = master
            s_opts["multimaster"] = True
            s_opts["beacons_leader"] = beacons_leader
            if beacons_leader:
                beacons_leader = False
            minion = self._create_minion_object(
                s_opts,
                s_opts["auth_timeout"],
                False,
                io_loop=self.io_loop,
                loaded_base_name="salt.loader.{}".format(s_opts["master"]),
                jid_queue=self.jid_queue,
            )
            self.io_loop.spawn_callback(self._connect_minion, minion)
        self.io_loop.call_later(timeout, self._check_minions)

    @salt.ext.tornado.gen.coroutine
    def _connect_minion(self, minion):
        """
        Create a minion, and asynchronously connect it to a master
        """
        last = 0  # never have we signed in
        auth_wait = minion.opts["acceptance_wait_time"]
        failed = False
        while True:
            try:
                if minion.opts.get("beacons_before_connect", False):
                    minion.setup_beacons(before_connect=True)
                if minion.opts.get("scheduler_before_connect", False):
                    minion.setup_scheduler(before_connect=True)
                if minion.opts.get("master_type", "str") != "disable":
                    yield minion.connect_master(failed=failed)
                minion.tune_in(start=False)
                self.minions.append(minion)
                break
            except SaltClientError as exc:
                yield minion.destroy_async()
                failed = True
                log.error(
                    "Error while bringing up minion for multi-master. Is "
                    "master at %s responding? The error message was %s",
                    minion.opts["master"],
                    exc,
                )
                if auth_wait < self.max_auth_wait:
                    auth_wait += self.auth_wait
                yield salt.ext.tornado.gen.sleep(auth_wait)  # TODO: log?
            except SaltMasterUnresolvableError:
                yield minion.destroy_async()
                err = (
                    "Master address: '{}' could not be resolved. Invalid or"
                    " unresolveable address. Set 'master' value in minion config.".format(
                        minion.opts["master"]
                    )
                )
                log.error(err)
                break
            except Exception as e:  # pylint: disable=broad-except
                yield minion.destroy_async()
                failed = True
                log.critical(
                    "Unexpected error while connecting to %s",
                    minion.opts["master"],
                    exc_info=True,
                )
                # Match SaltClientError path: without a delay, connect_master can be
                # retried in a tight loop and create zmq contexts faster than they are
                # torn down (libzMQ pthread / EMFILE failures on some hosts).
                if auth_wait < self.max_auth_wait:
                    auth_wait += self.auth_wait
                yield salt.ext.tornado.gen.sleep(auth_wait)

    # Multi Master Tune In
    def tune_in(self):
        """
        Bind to the masters

        This loop will attempt to create connections to masters it hasn't connected
        to yet, but once the initial connection is made it is up to ZMQ to do the
        reconnect (don't know of an API to get the state here in salt)
        """
        self._bind()

        # Fire off all the minion coroutines
        self._spawn_minions()

        # serve forever!
        self.io_loop.start()

    @property
    def restart(self):
        for minion in self.minions:
            if minion.restart:
                return True
        return False

    def stop(self, signum, parent_sig_handler):
        """
        Stop minions managed by the MinionManager

        Called from cli.daemons.Minion._handle_signals().
        Adds stop_async as callback to the io_loop to prevent blocking.
        """
        # Trip the resolve_dns() abort flag first so a minion currently
        # stuck in the synchronous DNS retry loop wakes up and releases
        # the io_loop, allowing stop_async (scheduled below) to actually
        # run. Without this, a SIGTERM that arrives while a master
        # hostname is unresolvable is silently swallowed until systemd
        # escalates to SIGKILL. See #69466.
        request_resolve_dns_abort()
        self.io_loop.add_callback(  # pylint: disable=not-callable
            self.stop_async, signum, parent_sig_handler
        )

    @salt.ext.tornado.gen.coroutine
    def stop_async(self, signum, parent_sig_handler):
        """
        Stop minions managed by the MinionManager allowing the io_loop to run
        and any remaining events to be processed before stopping the minions.
        """

        # Sleep to allow any remaining events to be processed.
        # This gives the minion time to send final "return" messages to the Master.
        # Ideally, we would dynamically wait for all pending messages to be flushed
        # from the I/O loop instead of using a static sleep amount, but for now
        # this 5-second window handles most cases.
        yield salt.ext.tornado.gen.sleep(5)

        # Continue to stop the minions
        for minion in self.minions:
            minion.process_manager.stop_restarting()
            minion.process_manager.send_signal_to_processes(signum)
            # kill any remaining processes
            minion.process_manager.kill_children()
            yield minion.destroy_async()
        if self.event_publisher is not None:
            self.event_publisher.close()
            self.event_publisher = None
        if self.event is not None:
            self.event.destroy()
            self.event = None

        # Call the parent signal handler
        parent_sig_handler(signum, None)


class Minion(MinionBase):
    """
    This class instantiates a minion, runs connections for a minion,
    and loads all of the functions into the minion
    """

    def __init__(
        self,
        opts,
        timeout=60,
        safe=True,
        loaded_base_name=None,
        io_loop=None,
        jid_queue=None,
        load_grains=True,
    ):  # pylint: disable=W0231
        """
        Pass in the options dict
        """
        # this means that the parent class doesn't know *which* master we connect to
        super().__init__(opts)

        # Clean up stale queue lock that might have been left behind if the minion
        # was killed forcefully (SIGKILL). This ensures recovery on restart.
        # In multimaster, each Minion instance has its own per-master lock path,
        # so this cleanup cannot interfere across masters sharing a cachedir.
        lock_path = salt.utils.state.queue_lock_path(self.opts)
        if os.path.isfile(lock_path):
            try:
                os.remove(lock_path)
                log.info("Removed stale lock file: %s", lock_path)
            except OSError:
                pass

        # Clean up orphaned running_ files from crashed minions
        # These can be left behind if minion crashes after rename but before cleanup
        self._cleanup_orphaned_queue_files()

        self.timeout = timeout
        self.safe = safe

        self._running = None
        self.subprocess_list = salt.utils.process.SubprocessList()
        self.loaded_base_name = loaded_base_name
        self.connected = False
        self.restart = False
        # Flag meaning minion has finished initialization including first connect to the master.
        # True means the Minion is fully functional and ready to handle events.
        self.ready = False
        self.jid_queue = [] if jid_queue is None else jid_queue
        self.periodic_callbacks = {}
        self.req_channel = None
        # Track when system resource limits are hit (EMFILE/ENFILE) to apply backpressure
        self._system_resource_limit_hit_timestamp = 0

        if io_loop is None:
            self.io_loop = salt.ext.tornado.ioloop.IOLoop.current()
        else:
            self.io_loop = io_loop

        # Warn if ZMQ < 3.2
        if zmq:
            if ZMQ_VERSION_INFO < (3, 2):
                log.warning(
                    "You have a version of ZMQ less than ZMQ 3.2! There are "
                    "known connection keep-alive issues with ZMQ < 3.2 which "
                    "may result in loss of contact with minions. Please "
                    "upgrade your ZMQ!"
                )
        # Late setup of the opts grains, so we can log from the grains
        # module.  If this is a proxy, however, we need to init the proxymodule
        # before we can get the grains.  We do this for proxies in the
        # post_master_init
        if not salt.utils.platform.is_proxy():
            if load_grains:
                self.opts["grains"] = salt.loader.grains(opts)
        else:
            if self.opts.get("beacons_before_connect", False):
                log.warning(
                    "'beacons_before_connect' is not supported "
                    "for proxy minions. Setting to False"
                )
                self.opts["beacons_before_connect"] = False
            if self.opts.get("scheduler_before_connect", False):
                log.warning(
                    "'scheduler_before_connect' is not supported "
                    "for proxy minions. Setting to False"
                )
                self.opts["scheduler_before_connect"] = False

        log.info("Creating minion process manager")

        if self.opts["random_startup_delay"]:
            sleep_time = random.randint(0, self.opts["random_startup_delay"])
            log.info(
                "Minion sleeping for %s seconds due to configured "
                "startup_delay between 0 and %s seconds",
                sleep_time,
                self.opts["random_startup_delay"],
            )
            time.sleep(sleep_time)

        self.process_manager = ProcessManager(name="MinionProcessManager")
        self.io_loop.spawn_callback(self.process_manager.run, **{"asynchronous": True})
        # We don't have the proxy setup yet, so we can't start engines
        # Engines need to be able to access __proxy__
        if not salt.utils.platform.is_proxy():
            self.io_loop.spawn_callback(
                salt.engines.start_engines, self.opts, self.process_manager
            )

        # Install the SIGINT/SIGTERM handlers if not done so far
        if signal.getsignal(signal.SIGINT) is signal.SIG_DFL:
            # No custom signal handling was added, install our own
            signal.signal(signal.SIGINT, self._handle_signals)

        if signal.getsignal(signal.SIGTERM) is signal.SIG_DFL:
            # No custom signal handling was added, install our own
            signal.signal(signal.SIGTERM, self._handle_signals)

    def _handle_signals(self, signum, sigframe):
        self._running = False
        # escalate the signals to the process manager
        self.process_manager._handle_signals(signum, sigframe)
        time.sleep(1)
        sys.exit(0)

    def _cleanup_orphaned_queue_files(self):
        """
        Clean up orphaned running_ queue files that may have been left behind
        if the minion crashed after renaming queued_ to running_ but before cleanup.
        """
        for queue_dir in (
            salt.utils.state.state_queue_dir(self.opts),
            salt.utils.state.job_queue_dir(self.opts),
        ):
            if not os.path.exists(queue_dir):
                continue

            try:
                for fn in os.listdir(queue_dir):
                    if not fn.startswith("running_") or not fn.endswith(".p"):
                        continue

                    path = os.path.join(queue_dir, fn)
                    try:
                        # Check if file is older than 5 minutes (300 seconds)
                        # This gives running jobs time to complete and clean up
                        stat_info = os.stat(path)
                        age_seconds = time.time() - stat_info.st_mtime

                        if age_seconds > 300:  # 5 minutes
                            log.info(
                                "Removing orphaned running queue file: %s (age: %.1fs)",
                                path,
                                age_seconds,
                            )
                            os.remove(path)
                    except OSError as exc:
                        log.debug(
                            "Could not check/cleanup running file %s: %s", path, exc
                        )
            except OSError as exc:
                log.debug("Could not list queue directory %s: %s", queue_dir, exc)

    def sync_connect_master(self, timeout=None, failed=False):
        """
        Block until we are connected to a master
        """
        self._sync_connect_master_success = False
        log.debug("sync_connect_master")

        def on_connect_master_future_done(future):
            self._sync_connect_master_success = True
            self.io_loop.stop()

        self._connect_master_future = self.connect_master(failed=failed)
        # finish connecting to master
        self._connect_master_future.add_done_callback(on_connect_master_future_done)
        if timeout:
            self.io_loop.call_later(timeout, self.io_loop.stop)
        try:
            self.io_loop.start()
        except KeyboardInterrupt:
            self.destroy()
        # I made the following 3 line oddity to preserve traceback.
        # Please read PR #23978 before changing, hopefully avoiding regressions.
        # Good luck, we're all counting on you.  Thanks.
        if self._connect_master_future.done():
            future_exception = self._connect_master_future.exception()
            if future_exception:
                exc_info = self._connect_master_future.exc_info()
                # This needs to be re-raised to preserve restart_on_error behavior.
                raise exc_info[0].with_traceback(exc_info[1], exc_info[2])
        if timeout and self._sync_connect_master_success is False:
            raise SaltDaemonNotRunning("Failed to connect to the salt-master")

    @salt.ext.tornado.gen.coroutine
    def connect_master(self, failed=False):
        """
        Return a future which will complete when you are connected to a master
        """
        if hasattr(self, "pub_channel") and self.pub_channel:
            self.pub_channel.on_recv(None)
            if hasattr(self.pub_channel, "auth"):
                self.pub_channel.auth.invalidate()
            if hasattr(self.pub_channel, "close"):
                self.pub_channel.close()
        if hasattr(self, "req_channel") and self.req_channel:
            yield self.req_channel.close_async()
            yield salt.ext.tornado.gen.sleep(0)
            self.req_channel = None

        # Consider refactoring so that eval_master does not have a subtle side-effect on the contents of the opts array
        master, self.pub_channel = yield self.eval_master(
            self.opts, self.timeout, self.safe, failed
        )

        # a long-running req channel
        self.req_channel = salt.channel.client.AsyncReqChannel.factory(
            self.opts, io_loop=self.io_loop
        )
        log.debug("Connecting minion's long-running req channel")
        yield self.req_channel.connect()
        yield self._post_master_init(master)

    @salt.ext.tornado.gen.coroutine
    def handle_payload(self, payload, reply_func):
        self.payloads.append(payload)
        yield reply_func(payload)
        self.payload_ack.notify()

    # TODO: better name...
    @salt.ext.tornado.gen.coroutine
    def _post_master_init(self, master):
        """
        Function to finish init after connecting to a master

        This is primarily loading modules, pillars, etc. (since they need
        to know which master they connected to)

        If this function is changed, please check ProxyMinion._post_master_init
        to see if those changes need to be propagated.

        Minions and ProxyMinions need significantly different post master setups,
        which is why the differences are not factored out into separate helper
        functions.
        """
        if self.connected:
            self.opts["master"] = master

            # Initialize pillar before loader to make pillar accessible in modules
            async_pillar = salt.pillar.get_async_pillar(
                self.opts,
                self.opts["grains"],
                self.opts["id"],
                self.opts["saltenv"],
                pillarenv=self.opts.get("pillarenv"),
            )
            self.opts["pillar"] = yield async_pillar.compile_pillar()
            async_pillar.destroy()

        if not self.ready:
            self._setup_core()
        elif self.connected and self.opts["pillar"]:
            # The pillar has changed due to the connection to the master.
            # Reload the functions so that they can use the new pillar data.
            (
                self.functions,
                self.returners,
                self.function_errors,
                self.executors,
            ) = self._load_modules()
            if hasattr(self, "schedule"):
                self.schedule.functions = self.functions
                self.schedule.returners = self.returners

        if not hasattr(self, "schedule"):
            self.schedule = salt.utils.schedule.Schedule(
                self.opts,
                self.functions,
                self.returners,
                cleanup=[master_event(type="alive")],
            )

        # add default scheduling jobs to the minions scheduler
        if self.opts["mine_enabled"] and "mine.update" in self.functions:
            self.schedule.add_job(
                {
                    "__mine_interval": {
                        "function": "mine.update",
                        "minutes": self.opts["mine_interval"],
                        "jid_include": True,
                        "maxrunning": 2,
                        "run_on_start": True,
                        "return_job": self.opts.get("mine_return_job", False),
                    }
                },
                persist=True,
            )
            log.info("Added mine.update to scheduler")
        else:
            self.schedule.delete_job("__mine_interval", persist=True)

        # add master_alive job if enabled
        if (
            self.opts["transport"] != "tcp"
            and self.opts["master_alive_interval"] > 0
            and self.connected
        ):
            self.schedule.add_job(
                {
                    master_event(type="alive", master=self.opts["master"]): {
                        "function": "status.master",
                        "seconds": self.opts["master_alive_interval"],
                        "jid_include": True,
                        "maxrunning": 1,
                        "return_job": False,
                        "kwargs": {"master": self.opts["master"], "connected": True},
                    }
                },
                persist=True,
            )
            if (
                self.opts["master_failback"]
                and "master_list" in self.opts
                and self.opts["master"] != self.opts["master_list"][0]
            ):
                self.schedule.add_job(
                    {
                        master_event(type="failback"): {
                            "function": "status.ping_master",
                            "seconds": self.opts["master_failback_interval"],
                            "jid_include": True,
                            "maxrunning": 1,
                            "return_job": False,
                            "kwargs": {"master": self.opts["master_list"][0]},
                        }
                    },
                    persist=True,
                )
            else:
                self.schedule.delete_job(master_event(type="failback"), persist=True)
        else:
            self.schedule.delete_job(
                master_event(type="alive", master=self.opts["master"]), persist=True
            )
            self.schedule.delete_job(master_event(type="failback"), persist=True)

    def _prep_mod_opts(self):
        """
        Returns a copy of the opts with key bits stripped out
        """
        mod_opts = {}
        for key, val in self.opts.items():
            if key == "logger":
                continue
            mod_opts[key] = val
        return mod_opts

    def _load_modules(
        self, force_refresh=False, notify=False, grains=None, opts=None, context=None
    ):
        """
        Return the functions and the returners loaded up from the loader
        module
        """
        opt_in = True
        if not opts:
            opts = self.opts
            opt_in = False
        # if this is a *nix system AND modules_max_memory is set, lets enforce
        # a memory limit on module imports
        # this feature ONLY works on *nix like OSs (resource module doesn't work on windows)
        modules_max_memory = False
        old_mem_limit = None
        if opts.get("modules_max_memory", -1) > 0 and HAS_PSUTIL and HAS_RESOURCE:
            log.debug(
                "modules_max_memory set, enforcing a maximum of %s",
                opts["modules_max_memory"],
            )
            modules_max_memory = True
            old_mem_limit = resource.getrlimit(resource.RLIMIT_AS)
            rss, vms = psutil.Process(os.getpid()).memory_info()[:2]
            mem_limit = rss + vms + opts["modules_max_memory"]
            resource.setrlimit(resource.RLIMIT_AS, (mem_limit, mem_limit))
        elif opts.get("modules_max_memory", -1) > 0:
            if not HAS_PSUTIL:
                log.error(
                    "Unable to enforce modules_max_memory because psutil is missing"
                )
            if not HAS_RESOURCE:
                log.error(
                    "Unable to enforce modules_max_memory because resource is missing"
                )

        # This might be a proxy minion
        if hasattr(self, "proxy"):
            proxy = self.proxy
        else:
            proxy = None

        if context is None:
            context = {}

        if grains is None:
            opts["grains"] = salt.loader.grains(
                opts, force_refresh, proxy=proxy, context=context
            )
        self.utils = salt.loader.utils(opts, proxy=proxy, context=context)

        if opts.get("multimaster", False):
            s_opts = copy.deepcopy(opts)
            functions = salt.loader.minion_mods(
                s_opts,
                utils=self.utils,
                proxy=proxy,
                loaded_base_name=self.loaded_base_name,
                notify=notify,
                context=context,
            )
        else:
            functions = salt.loader.minion_mods(
                opts,
                utils=self.utils,
                notify=notify,
                proxy=proxy,
                context=context,
            )
        returners = salt.loader.returners(opts, functions, proxy=proxy, context=context)
        errors = {}
        if "_errors" in functions:
            errors = functions["_errors"]
            functions.pop("_errors")

        # we're done, reset the limits!
        if modules_max_memory is True:
            resource.setrlimit(resource.RLIMIT_AS, old_mem_limit)

        executors = salt.loader.executors(opts, functions, proxy=proxy, context=context)

        if opt_in:
            self.opts = opts

        return functions, returners, errors, executors

    def _send_req_sync(self, load, timeout):
        with salt.utils.event.get_event("minion", opts=self.opts, listen=True) as event:
            request_id = str(uuid.uuid4())
            log.trace("Send request to main id=%s", request_id)
            event.fire_event(
                load,
                f"__master_req_channel_payload/{request_id}/{self.opts['master']}",
                timeout=timeout,
            )
            ret = event.get_event(
                tag=f"__master_req_channel_return/{request_id}",
                wait=timeout,
            )
            if ret:
                if ret.get("error"):
                    raise salt.exceptions.SaltReqTimeoutError(
                        f"Request timed out in main process: {ret['error']}"
                    )
                log.trace("Reply from main %s", request_id)
                return ret["ret"]
            raise salt.exceptions.SaltReqTimeoutError("Request timed out")

    @salt.ext.tornado.gen.coroutine
    def _send_req_async(self, load, timeout):
        # XXX: This is only used by syndic
        with salt.utils.event.get_event("minion", opts=self.opts, listen=True) as event:
            request_id = str(uuid.uuid4())
            log.trace("Send request to main id=%s", request_id)
            yield event.fire_event_async(
                load,
                f"__master_req_channel_payload/{request_id}/{self.opts['master']}",
                timeout=timeout,
            )
            start = time.time()
            while time.time() - start < timeout:
                ret = event.get_event(
                    tag=f"__master_req_channel_return/{request_id}", no_block=True
                )
                if ret:
                    break
                yield salt.ext.tornado.gen.sleep(0.3)
            else:
                raise TimeoutError("Did not recieve return event")
            log.trace("Reply from main %s", request_id)
            raise salt.ext.tornado.gen.Return(ret["ret"])

    @salt.ext.tornado.gen.coroutine
    def _send_req_async_main(self, load, timeout):
        """
        Send a request to the master's request server. To be called from the
        top level process in the main thread only. Worker threads and
        processess should call _send_req_sync or _send_req_async as nessecery.
        """
        ret = yield self.req_channel.send(
            load, timeout=timeout, tries=self.opts["return_retry_tries"]
        )
        raise salt.ext.tornado.gen.Return(ret)

    def _fire_master_prepare(
        self, data, tag, events, pretag, include_startup_grains=False
    ):
        load = {
            "id": self.opts["id"],
            "cmd": "_minion_event",
            "pretag": pretag,
            "tok": self.tok,
        }
        if events:
            load["events"] = events
        elif data and tag:
            load["data"] = data
            load["tag"] = tag
        elif not data and tag:
            load["data"] = {}
            load["tag"] = tag
        else:
            return

        if include_startup_grains:
            grains_to_add = {
                k: v
                for k, v in self.opts.get("grains", {}).items()
                if k in self.opts["start_event_grains"]
            }
            load["grains"] = grains_to_add
        return load

    @salt.ext.tornado.gen.coroutine
    def _fire_master_main(
        self,
        data=None,
        tag=None,
        events=None,
        pretag=None,
        timeout=60,
        timeout_handler=None,
        include_startup_grains=False,
    ):
        load = self._fire_master_prepare(
            data, tag, events, pretag, include_startup_grains
        )
        if timeout_handler is None:

            def handle_timeout(*_):
                log.info(
                    "fire_master failed: master could not be contacted. Request"
                    " timed out."
                )
                return True

            timeout_handler = handle_timeout

        yield self._send_req_async_main(load, timeout)

    def _fire_master(
        self,
        data=None,
        tag=None,
        events=None,
        pretag=None,
        timeout=60,
        timeout_handler=None,
        include_startup_grains=False,
    ):
        """
        Fire an event on the master, or drop message if unable to send.
        """
        load = self._fire_master_prepare(
            data, tag, events, pretag, include_startup_grains
        )
        try:
            self._send_req_sync(load, timeout)
        except salt.exceptions.SaltReqTimeoutError:
            log.info(
                "fire_master failed: master could not be contacted. Request timed"
                " out."
            )
            return False
        except Exception:  # pylint: disable=broad-except
            log.info("fire_master failed: %s", traceback.format_exc())
            return False
        return True

    @salt.ext.tornado.gen.coroutine
    def _handle_decoded_payload(self, data):
        """
        Override this method if you wish to handle the decoded data
        differently.
        """
        yield self._handle_decoded_payload_impl(data)

    async def _handle_decoded_payload_impl(self, data):
        """
        Async implementation of _handle_decoded_payload
        """
        # Ensure payload is unicode. Disregard failure to decode binary blobs.
        if "user" in data:
            log.info(
                "User %s Executing command %s with jid %s",
                data["user"],
                data["fun"],
                data["jid"],
            )
        else:
            log.info("Executing command %s with jid %s", data["fun"], data["jid"])
        log.debug("Command details %s", data)

        # Don't duplicate jobs
        log.trace("Started JIDs: %s", self.jid_queue)
        # Check bypass flag early to prevent deduplication of queued jobs
        bypass_check = data.get("__ignore_process_count_max", False)
        if self.jid_queue is not None:
            if data["jid"] in self.jid_queue:
                if not bypass_check:
                    return
            else:
                self.jid_queue.append(data["jid"])
                if len(self.jid_queue) > self.opts["minion_jid_queue_hwm"]:
                    self.jid_queue.pop(0)

        if isinstance(data["fun"], str):
            if data["fun"] == "sys.reload_modules":
                (
                    self.functions,
                    self.returners,
                    self.function_errors,
                    self.executors,
                ) = self._load_modules()
                self.schedule.functions = self.functions
                self.schedule.returners = self.returners

        if self.opts.get("grains_refresh_pre_exec"):
            if hasattr(self, "proxy"):
                proxy = self.proxy
            else:
                proxy = None
            self.opts["grains"] = salt.loader.grains(
                self.opts, force_refresh=True, proxy=proxy
            )

        # Check if we should bypass the process_count_max check
        # This is used for jobs that have been queued and are now being released
        bypass_process_count_max = data.pop("__ignore_process_count_max", False)

        # Enforce resource limits (FDs and Memory) before checking process counts
        # This safeguard is critical to prevent crashes under high load
        if not bypass_process_count_max:
            if not self._has_fd_headroom():
                log.warning("Insufficient FD headroom, queuing job %s", data["jid"])
                self._queue_job(data)
                return

            if not self._has_memory_headroom():
                log.warning("Insufficient memory headroom, queuing job %s", data["jid"])
                self._queue_job(data)
                return

        # Check process count and potentially queue - only acquire lock when needed
        if not bypass_process_count_max:
            # Use internal subprocess list for accurate counting
            # This is racy but acceptable for the common case
            running_processes = [
                p for p in self.subprocess_list.processes if p.is_alive()
            ]
            process_count = len(running_processes)
            process_count_max = self._get_effective_process_count_max()

            if process_count >= process_count_max:
                # At process limit - need to acquire lock for atomic queuing
                try:
                    async with salt.utils.state.acquire_async_queue_lock(self.opts):
                        # Re-check count under lock to avoid race
                        running_processes = [
                            p for p in self.subprocess_list.processes if p.is_alive()
                        ]
                        process_count = len(running_processes)
                        process_count_max = self._get_effective_process_count_max()

                        if process_count >= process_count_max:
                            log.warning(
                                "Maximum number of processes reached while executing jid %s,"
                                " queuing... (Running: %s, Max: %s)",
                                data["jid"],
                                process_count,
                                process_count_max,
                            )
                            self._queue_job(data)
                            return
                except salt.exceptions.FileLockError:
                    log.warning(
                        "Failed to acquire job_queue lock for jid %s, queuing anyway.",
                        data["jid"],
                    )
                    # If we can't get the lock, we assume high contention and queue it to be safe.
                    # Or we could just proceed (unsafe). Queuing is safer for stability.
                    self._queue_job(data)
                    return

        # Execute the job and get the process handle
        proc = self._invoke_execution(data)

        # Write placeholder proc file with the ACTUAL PID to prevent "Invisible Gap"
        # This ensures that when the child starts and checks 'running()', it sees itself.
        if proc:
            proc_dir = os.path.join(self.opts["cachedir"], "proc")
            if not os.path.isdir(proc_dir):
                try:
                    os.makedirs(proc_dir)
                except OSError:
                    pass

            proc_fn = os.path.join(proc_dir, str(data["jid"]))

            # Use the real PID from the handle (multiprocessing) or current PID (threading)
            real_pid = getattr(proc, "pid", os.getpid())
            if real_pid is None:
                real_pid = os.getpid()

            placeholder_data = data.copy()
            placeholder_data["pid"] = real_pid

            try:
                with salt.utils.files.fopen(proc_fn, "w+b") as fp_:
                    salt.payload.dump(placeholder_data, fp_)
            except OSError:
                log.error("Failed to write placeholder proc file %s", proc_fn)

        # Now that the placeholder proc file is written, we can safely delete
        # the running_ queue file to close the "invisible gap".
        for qf in ("_job_queue_file", "_state_queue_file"):
            if qf in data:
                try:
                    os.remove(data[qf])
                except OSError:
                    pass

    def _queue_job(self, data):
        """
        Queue a job to disk because process_count_max is reached.
        """
        queue_dir = salt.utils.state.job_queue_dir(self.opts)
        if not os.path.exists(queue_dir):
            try:
                os.makedirs(queue_dir)
            except OSError:
                pass

        # Use timestamp to ensure FIFO ordering
        # We use microseconds to avoid collisions
        jid = data.get("jid")
        fn = f"queued_{int(time.time() * 1000000)}_{jid}.p"
        path = os.path.join(queue_dir, fn)

        try:
            tmp_path = path + ".tmp"
            with salt.utils.files.fopen(tmp_path, "w+b") as fp_:
                salt.payload.dump(data, fp_)
            salt.utils.atomicfile.atomic_rename(tmp_path, path)
            log.info("Queued job %s to %s", jid, path)
        except OSError:
            log.error("Failed to write job queue file %s", path)

    def _has_fd_headroom(self, critical_only=False):
        """
        Check if we have enough file descriptors available to start a new process safely.
        Returns True if we have headroom, False otherwise.
        """
        if not HAS_RESOURCE:
            return True

        try:
            soft_limit, _ = resource.getrlimit(resource.RLIMIT_NOFILE)
            if soft_limit == resource.RLIM_INFINITY:
                return True

            # Count current open FDs
            # This is specific to Linux/Unix with /proc
            if os.path.isdir("/proc/self/fd"):
                current_fds = len(os.listdir("/proc/self/fd"))
            else:
                try:
                    import psutil

                    p = psutil.Process()
                    current_fds = p.num_fds()
                except Exception:  # pylint: disable=broad-exception-caught
                    return True

            # Global critical check (always enforced)
            if current_fds >= soft_limit - 100:
                log.warning(
                    "FD critical limit reached (Open: %s, Limit: %s). Pausing queue processing.",
                    current_fds,
                    soft_limit,
                )
                return False

            if not critical_only:
                # Check if we are running in threading mode (multiprocessing=False)
                # If so, we need to be more conservative with file descriptors
                if not self.opts.get("multiprocessing", True):
                    # Use 80% of the available file descriptors as the limit (20% headroom)
                    limit = int(soft_limit * 0.8)
                    if current_fds >= limit:
                        log.warning(
                            "FD limit reached (Open: %s, Limit: %s, Threshold: %s). Pausing queue processing.",
                            current_fds,
                            soft_limit,
                            limit,
                        )
                        return False

            return True
        except Exception:  # pylint: disable=broad-exception-caught
            return True

    def _has_memory_headroom(self):
        """
        Check if we have enough memory to start a new process.
        Returns True if we have headroom, False otherwise.
        """
        if not HAS_PSUTIL:
            return True

        try:
            import psutil

            mem = psutil.virtual_memory()
            if mem.percent > 95:
                log.warning(
                    "Memory limit reached (Used: %s%%). Pausing queue processing.",
                    mem.percent,
                )
                return False
        except Exception:  # pylint: disable=broad-exception-caught
            return True
        return True

    def _get_effective_process_count_max(self):
        """
        Calculate the effective process_count_max.
        If configured value is > 0, use it.
        If <= 0 (unlimited), calculate a safe limit based on RLIMIT_NOFILE.
        """
        limit = self.opts.get("process_count_max")
        if limit is not None and limit > 0:
            return limit

        if not HAS_RESOURCE:
            return 100  # Conservative default

        try:
            soft_limit, _ = resource.getrlimit(resource.RLIMIT_NOFILE)
            if soft_limit == resource.RLIM_INFINITY:
                return 1000  # Large but not unlimited
        except Exception:  # pylint: disable=broad-exception-caught
            return 100

        # Conservative estimates:
        # Threading: 15 FDs per job
        # Multiprocessing: 5 FDs per job (IPC overhead in parent)
        is_threading = not self.opts.get("multiprocessing", True)
        fds_per_job = 15 if is_threading else 5

        # Reserve FDs for the main process base usage
        reserved = 100

        safe_limit = (soft_limit - reserved) // fds_per_job
        return max(1, safe_limit)

    def _invoke_execution(self, data):
        # We stash an instance references to allow for the socket
        # communication in Windows. You can't pickle functions, and thus
        # python needs to be able to reconstruct the reference on the other
        # side.

        instance = self
        creds_map = None
        multiprocessing_enabled = self.opts.get("multiprocessing", True)
        name = "ProcessPayload(jid={})".format(data["jid"])
        if multiprocessing_enabled:
            if salt.utils.platform.spawning_platform():
                # let python reconstruct the minion on the other side if we're
                # running on windows
                instance = None
                creds_map = salt.crypt.AsyncAuth.creds_map
            with default_signals(signal.SIGINT, signal.SIGTERM):
                process = SignalHandlingProcess(
                    target=self._target,
                    name=name,
                    args=(instance, self.opts, data, self.connected, creds_map),
                )
        else:
            process = threading.Thread(
                target=self._target,
                args=(instance, self.opts, data, self.connected, creds_map),
                name=name,
            )

        if multiprocessing_enabled:
            with default_signals(signal.SIGINT, signal.SIGTERM):
                # Reset current signals before starting the process in
                # order not to inherit the current signal handlers
                try:
                    process.start()
                except OSError as exc:
                    if exc.errno in (
                        errno.EAGAIN,
                        errno.EMFILE,
                        errno.ENFILE,
                        errno.ENOMEM,
                    ):
                        log.warning(
                            "System resource limit reached while starting process for jid %s, queuing job. Error: %s",
                            data["jid"],
                            exc,
                        )
                        self._system_resource_limit_hit_timestamp = time.time()
                        self._queue_job(data)
                        return None
                    raise
        else:
            try:
                process.start()
            except OSError as exc:
                if exc.errno in (
                    errno.EAGAIN,
                    errno.EMFILE,
                    errno.ENFILE,
                    errno.ENOMEM,
                ):
                    log.warning(
                        "System resource limit reached while starting thread for jid %s, queuing job. Error: %s",
                        data["jid"],
                        exc,
                    )
                    self._system_resource_limit_hit_timestamp = time.time()
                    self._queue_job(data)
                    return None
                raise
        self.subprocess_list.add(process)
        return process

    def setup_process_queue_processing(self):
        """
        Set up the process queue processing.
        """
        if "process_queue" not in self.periodic_callbacks:
            self.add_periodic_callback(
                "process_queue", self.process_process_queue, interval=0.3
            )

    def process_process_queue(self):
        """
        Check the process queue for pending jobs and execute them if slots are available.
        Runs as an async task on the main loop.
        """
        if getattr(self, "_process_queue_processing_active", False):
            return

        self._process_queue_processing_active = True
        self.io_loop.spawn_callback(self._process_process_queue_async)

    @salt.ext.tornado.gen.coroutine
    def _process_process_queue_async(self):
        """
        Async body of process_process_queue.
        """
        yield self._process_process_queue_async_impl()

    async def _process_process_queue_async_impl(self):
        """
        Async implementation of _process_process_queue_async
        """
        try:
            queue_dir = salt.utils.state.job_queue_dir(self.opts)
            if not os.path.exists(queue_dir):
                return

            # Check process count max first to avoid lock contention if we are obviously full
            # This is an optimization; we check again under lock.
            process_count_max = self._get_effective_process_count_max()
            # If process_count_max is <= 0 (unlimited), we still check the queue because we might
            # have queued jobs due to system resource exhaustion (OS limits).

            # Acquire shared queue lock (protects both state_queue and job_queue)
            try:
                # We use a short timeout because we run every 1s.
                # If we can't get it, we'll try next time.
                async with salt.utils.state.acquire_async_queue_lock(self.opts):
                    # Check actual process count
                    # Use internal subprocess list for accurate counting
                    running_processes = [
                        p for p in self.subprocess_list.processes if p.is_alive()
                    ]
                    process_count = len(running_processes)
                    process_count_max = self._get_effective_process_count_max()

                    if process_count >= process_count_max:
                        return

                    # Backpressure: If we recently hit system resource limits, pause processing
                    # to allow the system to recover and drain.
                    if self._system_resource_limit_hit_timestamp > 0:
                        # 5 second cool-down period
                        if time.time() - self._system_resource_limit_hit_timestamp < 5:
                            log.debug(
                                "Backpressure active: Pausing queue processing due to recent resource exhaustion."
                            )
                            return
                        else:
                            self._system_resource_limit_hit_timestamp = 0

                    # Proactive check for FD limits before trying to pop anything
                    if not self._has_fd_headroom():
                        log.debug(
                            "Backpressure active: Pausing queue processing due to approaching FD limit."
                        )
                        self._system_resource_limit_hit_timestamp = time.time()
                        return

                    # Check for queued jobs
                    files = []
                    try:
                        for fn in os.listdir(queue_dir):
                            if fn.startswith("queued_") and fn.endswith(".p"):
                                files.append(fn)
                    except OSError:
                        pass

                    if not files:
                        return

                    log.info(
                        "Process queue processing: found %d queued files (Running: %d, Max: %d)",
                        len(files),
                        process_count,
                        process_count_max,
                    )

                    # Sort by timestamp (FIFO)
                    files.sort()

                    # Calculate slots available
                    if process_count_max > 0:
                        slots_available = max(0, process_count_max - process_count)
                    else:
                        # If unlimited (but queued due to OS limits), assume we can try a batch.
                        # We use a conservative batch size to avoid hitting limits again immediately.
                        slots_available = 10

                    # Process up to slots_available files
                    for fn in files[:slots_available]:
                        path = os.path.join(queue_dir, fn)

                        # Re-check process count before processing each job (count may have changed)
                        current_process_count = len(
                            [p for p in self.subprocess_list.processes if p.is_alive()]
                        )
                        current_process_count_max = (
                            self._get_effective_process_count_max()
                        )

                        if current_process_count >= current_process_count_max:
                            log.debug(
                                "Process queue processing: Process count changed, stopping batch. "
                                "Current: %d, Max: %d",
                                current_process_count,
                                current_process_count_max,
                            )
                            break

                        try:
                            with salt.utils.files.fopen(path, "rb") as fp_:
                                data = salt.payload.load(fp_)
                        except (OSError, ValueError) as exc:
                            if isinstance(exc, OSError) and exc.errno in (
                                errno.EMFILE,
                                errno.ENFILE,
                            ):
                                log.error(
                                    "Process queue processing: Too many open files, cannot read queued job %s. Waiting.",
                                    fn,
                                )
                                # If we can't read one due to EMFILE, likely can't read others. Stop this batch.
                                break
                            log.error("Failed to load queued job %s, removing.", fn)
                            try:
                                os.remove(path)
                            except OSError:
                                pass
                            continue

                        # Mark to bypass checks (we already checked count)
                        data["__ignore_process_count_max"] = True

                        log.info("Re-submitting queued job %s", data.get("jid"))

                        if hasattr(self, "io_loop"):
                            self.io_loop.spawn_callback(
                                self._handle_decoded_payload, data
                            )
                        else:
                            self.io_loop.spawn_callback(
                                self._handle_decoded_payload, data
                            )

                        # Rename file to running_ to avoid duplicate execution
                        # and to close the invisible gap for check_prior_running_states
                        running_fn = fn.replace("queued_", "running_", 1)
                        running_path = os.path.join(queue_dir, running_fn)
                        try:
                            os.rename(path, running_path)
                            data["_job_queue_file"] = running_path
                        except OSError:
                            pass

            except (salt.exceptions.FileLockError, OSError) as exc:
                if isinstance(exc, salt.exceptions.FileLockError) or (
                    isinstance(exc, OSError)
                    and exc.errno in (errno.EMFILE, errno.ENFILE)
                ):
                    log.error(
                        "Process queue processing: Unable to acquire queue lock due to system resource exhaustion (%s). Waiting.",
                        exc,
                    )
                    return
                raise
        except Exception:  # pylint: disable=broad-exception-caught
            log.critical("Process queue processing failed", exc_info=True)
        finally:
            self._process_queue_processing_active = False

    def ctx(self):
        """
        Return a single context manager for the minion's data
        """
        exitstack = contextlib.ExitStack()
        exitstack.enter_context(self.functions.context_dict.clone())
        exitstack.enter_context(self.returners.context_dict.clone())
        exitstack.enter_context(self.executors.context_dict.clone())
        return exitstack

    @classmethod
    def _target(cls, minion_instance, opts, data, connected, creds_map):
        if creds_map:
            salt.crypt.AsyncAuth.creds_map = creds_map
        if not minion_instance:
            minion_instance = cls(opts, load_grains=False)
            minion_instance.connected = connected
            if not hasattr(minion_instance, "functions"):
                (
                    functions,
                    returners,
                    function_errors,
                    executors,
                ) = minion_instance._load_modules(grains=opts["grains"])
                minion_instance.functions = functions
                minion_instance.returners = returners
                minion_instance.function_errors = function_errors
                minion_instance.executors = executors
            if not hasattr(minion_instance, "proc_dir"):
                uid = salt.utils.user.get_uid(user=opts.get("user", None))
                minion_instance.proc_dir = get_proc_dir(opts["cachedir"], uid=uid)

        def run_func(minion_instance, opts, data):
            if isinstance(data["fun"], tuple) or isinstance(data["fun"], list):
                return Minion._thread_multi_return(minion_instance, opts, data)
            else:
                return Minion._thread_return(minion_instance, opts, data)

        with salt.ext.tornado.stack_context.StackContext(
            functools.partial(RequestContext, {"data": data, "opts": opts})
        ):
            with salt.ext.tornado.stack_context.StackContext(minion_instance.ctx):
                run_func(minion_instance, opts, data)

    def _execute_job_function(
        self, function_name, function_args, executors, opts, data
    ):
        """
        Executes a function within a job given it's name, the args and the executors.
        It also checks if the function is allowed to run if 'blackout mode' is enabled.
        """
        minion_blackout_violation = False
        if self.connected and self.opts["pillar"].get("minion_blackout", False):
            whitelist = self.opts["pillar"].get("minion_blackout_whitelist", [])
            # this minion is blacked out. Only allow saltutil.refresh_pillar and the whitelist
            if (
                function_name != "saltutil.refresh_pillar"
                and function_name not in whitelist
            ):
                minion_blackout_violation = True
        # use minion_blackout_whitelist from grains if it exists
        if self.opts["grains"].get("minion_blackout", False):
            whitelist = self.opts["grains"].get("minion_blackout_whitelist", [])
            if (
                function_name != "saltutil.refresh_pillar"
                and function_name not in whitelist
            ):
                minion_blackout_violation = True
        if minion_blackout_violation:
            raise SaltInvocationError(
                "Minion in blackout mode. Set 'minion_blackout' "
                "to False in pillar or grains to resume operations. Only "
                "saltutil.refresh_pillar allowed in blackout mode."
            )

        if function_name in self.functions:
            func = self.functions[function_name]
            args, kwargs = load_args_and_kwargs(func, function_args, data)
        else:
            # only run if function_name is not in minion_instance.functions and allow_missing_funcs is True
            func = function_name
            args, kwargs = function_args, data
        self.functions.pack["__context__"]["retcode"] = 0

        if isinstance(executors, str):
            executors = [executors]
        elif not isinstance(executors, list) or not executors:
            raise SaltInvocationError(
                "Wrong executors specification: {}. String or non-empty list expected".format(
                    executors
                )
            )
        if opts.get("sudo_user", "") and executors[-1] != "sudo":
            executors[-1] = "sudo"  # replace the last one with sudo
        log.trace("Executors list %s", executors)  # pylint: disable=no-member

        for name in executors:
            fname = f"{name}.execute"
            if fname not in self.executors:
                raise SaltInvocationError(f"Executor '{name}' is not available")
            return_data = self.executors[fname](opts, data, func, args, kwargs)
            if return_data is not None:
                return return_data

        return None

    @classmethod
    def _thread_return(cls, minion_instance, opts, data):
        """
        This method should be used as a threading target, start the actual
        minion side execution.
        """
        minion_instance.gen_modules()
        fn_ = os.path.join(minion_instance.proc_dir, str(data["jid"]))

        if opts.get("multiprocessing", True):
            salt.utils.process.appendproctitle(f"{cls.__name__}._thread_return")

        sdata = {"pid": os.getpid()}
        sdata.update(data)
        log.info("Starting a new job %s with PID %s", data["jid"], sdata["pid"])
        with salt.utils.files.fopen(fn_, "w+b") as fp_:
            fp_.write(salt.payload.dumps(sdata))
        ret = {"success": False}
        function_name = data["fun"]
        function_args = data["arg"]
        executors = (
            data.get("module_executors")
            or getattr(minion_instance, "module_executors", [])
            or opts.get("module_executors", ["direct_call"])
        )
        allow_missing_funcs = any(
            [
                minion_instance.executors[f"{executor}.allow_missing_func"](
                    function_name
                )
                for executor in executors
                if f"{executor}.allow_missing_func" in minion_instance.executors
            ]
        )
        try:
            if (
                function_name in minion_instance.functions
                or allow_missing_funcs is True
            ):
                try:
                    return_data = minion_instance._execute_job_function(
                        function_name, function_args, executors, opts, data
                    )
                    log.info(
                        "Job %s execution finished, return_data: %s",
                        data["jid"],
                        return_data,
                    )

                    if isinstance(return_data, types.GeneratorType):
                        ind = 0
                        iret = {}
                        for single in return_data:
                            if isinstance(single, dict) and isinstance(iret, dict):
                                iret.update(single)
                            else:
                                if not iret:
                                    iret = []
                                iret.append(single)
                            tag = tagify(
                                [data["jid"], "prog", opts["id"], str(ind)], "job"
                            )
                            event_data = {"return": single}
                            minion_instance._fire_master(event_data, tag)
                            ind += 1
                        ret["return"] = iret
                    else:
                        ret["return"] = return_data

                    retcode = minion_instance.functions.pack["__context__"].get(
                        "retcode", salt.defaults.exitcodes.EX_OK
                    )
                    if retcode == salt.defaults.exitcodes.EX_OK:
                        # No nonzero retcode in __context__ dunder. Check if return
                        # is a dictionary with a "result" or "success" key.
                        try:
                            if isinstance(return_data, dict):
                                func_result = all(
                                    return_data.get(x, True)
                                    for x in ("result", "success")
                                )
                            else:
                                func_result = True
                        except Exception:  # pylint: disable=broad-except
                            # return data is not a dict
                            func_result = True
                        if not func_result:
                            retcode = salt.defaults.exitcodes.EX_GENERIC

                    ret["retcode"] = retcode
                    ret["success"] = retcode == salt.defaults.exitcodes.EX_OK
                except CommandNotFoundError as exc:
                    msg = f"Command required for '{function_name}' not found"
                    log.debug(msg, exc_info=True)
                    ret["return"] = f"{msg}: {exc}"
                    ret["out"] = "nested"
                    ret["retcode"] = salt.defaults.exitcodes.EX_GENERIC
                except CommandExecutionError as exc:
                    log.error(
                        "A command in '%s' had a problem: %s",
                        function_name,
                        exc,
                        exc_info_on_loglevel=logging.DEBUG,
                    )
                    ret["return"] = f"ERROR: {exc}"
                    ret["out"] = "nested"
                    ret["retcode"] = salt.defaults.exitcodes.EX_GENERIC
                except SaltInvocationError as exc:
                    log.error(
                        "Problem executing '%s': %s",
                        function_name,
                        exc,
                        exc_info_on_loglevel=logging.DEBUG,
                    )
                    ret["return"] = f"ERROR executing '{function_name}': {exc}"
                    ret["out"] = "nested"
                    ret["retcode"] = salt.defaults.exitcodes.EX_GENERIC
                except SaltClientError as exc:
                    log.error(
                        "Problem executing '%s': %s",
                        function_name,
                        exc,
                    )
                    ret["return"] = f"ERROR executing '{function_name}': {exc}"
                    ret["out"] = "nested"
                    ret["retcode"] = salt.defaults.exitcodes.EX_GENERIC
                except TypeError as exc:
                    # XXX: This can ba extreemly missleading when something outside of a
                    # execution module call raises a TypeError. Make this it's own
                    # type of exception when we start validating state and
                    # execution argument module inputs.
                    msg = "Passed invalid arguments to {}: {}\n{}".format(
                        function_name,
                        exc,
                        minion_instance.functions[function_name].__doc__ or "",
                    )
                    log.warning(msg, exc_info_on_loglevel=logging.DEBUG)
                    ret["return"] = msg
                    ret["out"] = "nested"
                    ret["retcode"] = salt.defaults.exitcodes.EX_GENERIC
                except Exception:  # pylint: disable=broad-except
                    msg = "The minion function caused an exception"
                    log.warning(msg, exc_info_on_loglevel=True)
                    salt.utils.error.fire_exception(
                        salt.exceptions.MinionError(msg), opts, job=data
                    )
                    ret["return"] = f"{msg}: {traceback.format_exc()}"
                    ret["out"] = "nested"
                    ret["retcode"] = salt.defaults.exitcodes.EX_GENERIC
            else:
                docs = minion_instance.functions["sys.doc"](f"{function_name}*")
                if docs:
                    docs[function_name] = minion_instance.functions.missing_fun_string(
                        function_name
                    )
                    ret["return"] = docs
                else:
                    ret["return"] = minion_instance.functions.missing_fun_string(
                        function_name
                    )
                    mod_name = function_name.split(".")[0]
                    if mod_name in minion_instance.function_errors:
                        ret["return"] += " Possible reasons: '{}'".format(
                            minion_instance.function_errors[mod_name]
                        )
                ret["success"] = False
                ret["retcode"] = salt.defaults.exitcodes.EX_GENERIC
                ret["out"] = "nested"

            if isinstance(ret["return"], dict) and ret["return"].get("__no_return__"):
                # This is used to suppress the return for queued jobs
                # The job will be executed later and will return then
                # TODO: make this a configurable feature in the future
                log.trace(
                    "Suppressing return for job %s because __no_return__ is set",
                    data["jid"],
                )
                return

            ret["jid"] = data["jid"]
            ret["fun"] = data["fun"]
            ret["fun_args"] = data["arg"]
            if "user" in data:
                ret["user"] = data["user"]
            if "master_id" in data:
                ret["master_id"] = data["master_id"]
            if "metadata" in data:
                if isinstance(data["metadata"], dict):
                    ret["metadata"] = data["metadata"]
                else:
                    log.warning(
                        "The metadata parameter must be a dictionary. Ignoring."
                    )
            if minion_instance.connected:
                minion_instance._return_pub(
                    ret,
                    timeout=minion_instance.opts["return_retry_tries"]
                    * minion_instance._return_retry_timer(max=True),
                )
            else:
                log.warning(
                    "Minion not connected, cannot return data for job %s", data["jid"]
                )

            # Add default returners from minion config
            # Should have been converted to comma-delimited string already
            if isinstance(opts.get("return"), str):
                if data["ret"]:
                    data["ret"] = ",".join((data["ret"], opts["return"]))
                else:
                    data["ret"] = opts["return"]

            log.debug("minion return: %s", ret)
            # TODO: make a list? Seems odd to split it this late :/
            if data["ret"] and isinstance(data["ret"], str):
                if "ret_config" in data:
                    ret["ret_config"] = data["ret_config"]
                if "ret_kwargs" in data:
                    ret["ret_kwargs"] = data["ret_kwargs"]
                ret["id"] = opts["id"]
                for returner in set(data["ret"].split(",")):
                    try:
                        returner_str = f"{returner}.returner"
                        if returner_str in minion_instance.returners:
                            minion_instance.returners[returner_str](ret)
                        else:
                            returner_err = minion_instance.returners.missing_fun_string(
                                returner_str
                            )
                            log.error(
                                "Returner %s could not be loaded: %s",
                                returner_str,
                                returner_err,
                            )
                    except Exception as exc:  # pylint: disable=broad-except
                        log.exception(
                            "The return failed for job %s: %s", data["jid"], exc
                        )
        finally:
            try:
                os.remove(fn_)
            except OSError:
                pass

    @classmethod
    def _thread_multi_return(cls, minion_instance, opts, data):
        """
        This method should be used as a threading target, start the actual
        minion side execution.
        """
        minion_instance.gen_modules()
        fn_ = os.path.join(minion_instance.proc_dir, str(data["jid"]))

        if opts.get("multiprocessing", True):
            salt.utils.process.appendproctitle(f"{cls.__name__}._thread_multi_return")

        sdata = {"pid": os.getpid()}
        sdata.update(data)
        log.info("Starting a new job with PID %s", sdata["pid"])
        try:
            with salt.utils.files.fopen(fn_, "w+b") as fp_:
                fp_.write(salt.payload.dumps(sdata))
        except OSError as exc:
            if exc.errno in (errno.EAGAIN, errno.EMFILE, errno.ENFILE, errno.ENOMEM):
                log.error(
                    "System resource limit reached while writing proc file for job %s: %s. Aborting.",
                    data["jid"],
                    exc,
                )
                minion_instance._system_resource_limit_hit_timestamp = time.time()
                # If we can't write the proc file, we shouldn't run the job because
                # we can't track it. This will prevent "ghost" jobs.
                # Since we are already in the child process/thread, we just return.
                # The parent will see the process die.
                # However, for queue processing to work, we need to handle this earlier.
                # But here, we just fail gracefully instead of crashing hard.
                return
            raise

        multifunc_ordered = opts.get("multifunc_ordered", False)
        num_funcs = len(data["fun"])
        if multifunc_ordered:
            ret = {
                "return": [None] * num_funcs,
                "retcode": [None] * num_funcs,
                "success": [False] * num_funcs,
            }
        else:
            ret = {"return": {}, "retcode": {}, "success": {}}
        executors = (
            data.get("module_executors")
            or getattr(minion_instance, "module_executors", [])
            or opts.get("module_executors", ["direct_call"])
        )

        try:
            for ind in range(0, num_funcs):
                function_name = data["fun"][ind]
                function_args = data["arg"][ind]
                if not multifunc_ordered:
                    ret["success"][function_name] = False
                try:
                    return_data = minion_instance._execute_job_function(
                        function_name, function_args, executors, opts, data
                    )

                    key = ind if multifunc_ordered else data["fun"][ind]
                    ret["return"][key] = return_data
                    retcode = minion_instance.functions.pack["__context__"].get(
                        "retcode", 0
                    )
                    if retcode == 0:
                        # No nonzero retcode in __context__ dunder. Check if return
                        # is a dictionary with a "result" or "success" key.
                        try:
                            if isinstance(ret["return"][key], dict):
                                func_result = all(
                                    ret["return"][key].get(x, True)
                                    for x in ("result", "success")
                                )
                            else:
                                func_result = True
                        except Exception:  # pylint: disable=broad-except
                            # return data is not a dict
                            func_result = True
                        if not func_result:
                            retcode = 1

                    ret["retcode"][key] = retcode
                    ret["success"][key] = retcode == 0
                except Exception as exc:  # pylint: disable=broad-except
                    trb = traceback.format_exc()
                    log.warning("The minion function caused an exception: %s", exc)
                    if multifunc_ordered:
                        ret["return"][ind] = trb
                    else:
                        ret["return"][data["fun"][ind]] = trb
                ret["jid"] = data["jid"]
                ret["fun"] = data["fun"]
                ret["fun_args"] = data["arg"]
                if "user" in data:
                    ret["user"] = data["user"]
            if "metadata" in data:
                ret["metadata"] = data["metadata"]
            if minion_instance.connected:
                log.info("Attempting to return data for job %s", data["jid"])
                minion_instance._return_pub(ret)
            else:
                log.warning(
                    "Minion not connected, cannot return data for job %s", data["jid"]
                )
        finally:
            try:
                os.remove(fn_)
            except OSError:
                pass
        if data["ret"]:
            if "ret_config" in data:
                ret["ret_config"] = data["ret_config"]
            if "ret_kwargs" in data:
                ret["ret_kwargs"] = data["ret_kwargs"]
            for returner in set(data["ret"].split(",")):
                ret["id"] = opts["id"]
                try:
                    minion_instance.returners[f"{returner}.returner"](ret)
                except Exception as exc:  # pylint: disable=broad-except
                    log.error("The return failed for job %s: %s", data["jid"], exc)

    def _prepare_return_pub(self, ret, ret_cmd="_return"):
        jid = ret.get("jid", ret.get("__jid__"))
        fun = ret.get("fun", ret.get("__fun__"))
        fn_ = os.path.join(self.proc_dir, str(jid))
        if os.path.isfile(fn_):
            try:
                os.remove(fn_)
            except OSError:
                # The file is gone already
                pass
        log.info("Returning information for job: %s", jid)
        if ret.get("comment") == "Job queued for execution":
            log.warning("Sending 'Job Queued' return for job %s", jid)
        log.trace("Return data: %s", ret)
        if ret_cmd == "_syndic_return":
            load = {
                "cmd": ret_cmd,
                "id": self.opts["uid"],
                "jid": jid,
                "fun": fun,
                "arg": ret.get("arg"),
                "tgt": ret.get("tgt"),
                "tgt_type": ret.get("tgt_type"),
                "load": ret.get("__load__"),
            }
            if "__master_id__" in ret:
                load["master_id"] = ret["__master_id__"]
            load["return"] = {}
            for key, value in ret.items():
                if key.startswith("__"):
                    continue
                load["return"][key] = value
        else:
            load = {"cmd": ret_cmd, "id": self.opts["id"]}
            for key, value in ret.items():
                load[key] = value

        if "out" in ret:
            if isinstance(ret["out"], str):
                load["out"] = ret["out"]
            else:
                log.error("Invalid outputter %s. This is likely a bug.", ret["out"])
        else:
            try:
                oput = self.functions[fun].__outputter__
            except (KeyError, AttributeError, TypeError):
                pass
            else:
                if isinstance(oput, str):
                    load["out"] = oput
        if self.opts["cache_jobs"]:
            # Local job cache has been enabled
            if ret["jid"] == "req":
                ret["jid"] = salt.utils.jid.gen_jid(self.opts)
            try:
                salt.utils.minion.cache_jobs(self.opts, ret["jid"], ret)
            except OSError as exc:
                if exc.errno in (errno.EMFILE, errno.ENFILE):
                    log.error(
                        "System resource limit reached while caching job %s: %s",
                        ret["jid"],
                        exc,
                    )
                    self._system_resource_limit_hit_timestamp = time.time()
                else:
                    raise
        return load

    @salt.ext.tornado.gen.coroutine
    def _return_pub_main(self, ret, ret_cmd="_return", timeout=60):
        jid = ret.get("jid", ret.get("__jid__"))
        load = self._prepare_return_pub(ret, ret_cmd)
        if not self.opts["pub_ret"]:
            return ""

        def timeout_handler(*_):
            log.warning(
                "The minion failed to return the job information for job %s. "
                "This is often due to the master being shut down or "
                "overloaded. If the master is running, consider increasing "
                "the worker_threads value.",
                jid,
            )
            return True

        try:
            ret_val = yield self._send_req_async_main(load, timeout=timeout)
        except SaltReqTimeoutError:
            timeout_handler()
            ret_val = ""
        log.trace("ret_val = %s", ret_val)  # pylint: disable=no-member
        raise salt.ext.tornado.gen.Return(ret_val)

    def _return_pub(self, ret, ret_cmd="_return", timeout=60):
        """
        Return the data from the executed command to the master server
        """
        jid = ret.get("jid", ret.get("__jid__"))
        load = self._prepare_return_pub(ret, ret_cmd)
        if not self.opts["pub_ret"]:
            return ""

        def timeout_handler(*_):
            log.warning(
                "The minion failed to return the job information for job %s. "
                "This is often due to the master being shut down or "
                "overloaded. If the master is running, consider increasing "
                "the worker_threads value.",
                jid,
            )
            return True

        # Ensure the worker waits at least as long as the main process may
        # spend retrying, so it doesn't time out before the main process
        # can signal back with either a result or an error event.
        retry_budget = (
            self._return_retry_timer(max=True) * self.opts["return_retry_tries"]
        )
        effective_timeout = max(timeout, retry_budget)

        try:
            ret_val = self._send_req_sync(load, timeout=effective_timeout)
        except SaltReqTimeoutError:
            timeout_handler()
            return ""
        log.trace("ret_val = %s", ret_val)  # pylint: disable=no-member
        return ret_val

    def _return_pub_multi(self, rets, ret_cmd="_return", timeout=60, sync=True):
        """
        Return the data from the executed command to the master server
        """
        # XXX: This is only used by syndic and should be moved to the Syndic class.
        # XXX: The sync flag is only called with sync=False. Which also means
        # deprecating sync means we can remove Minion._send_req_async.
        if not isinstance(rets, list):
            rets = [rets]
        jids = {}
        for ret in rets:
            jid = ret.get("jid", ret.get("__jid__"))
            fun = ret.get("fun", ret.get("__fun__"))
            fn_ = os.path.join(self.proc_dir, str(jid))
            if os.path.isfile(fn_):
                try:
                    os.remove(fn_)
                except OSError:
                    # The file is gone already
                    pass
            log.info("Returning information for job: %s", jid)
            load = jids.setdefault(jid, {})
            if ret_cmd == "_syndic_return":
                if not load:
                    load.update(
                        {
                            "id": self.opts["id"],
                            "jid": jid,
                            "fun": fun,
                            "arg": ret.get("arg"),
                            "tgt": ret.get("tgt"),
                            "tgt_type": ret.get("tgt_type"),
                            "load": ret.get("__load__"),
                            "return": {},
                        }
                    )
                if "__master_id__" in ret:
                    load["master_id"] = ret["__master_id__"]
                for key, value in ret.items():
                    if key.startswith("__"):
                        continue
                    load["return"][key] = value
            else:
                load.update({"id": self.opts["id"]})
                for key, value in ret.items():
                    load[key] = value

            if "out" in ret:
                if isinstance(ret["out"], str):
                    load["out"] = ret["out"]
                else:
                    log.error("Invalid outputter %s. This is likely a bug.", ret["out"])
            else:
                try:
                    oput = self.functions[fun].__outputter__
                except (KeyError, AttributeError, TypeError):
                    pass
                else:
                    if isinstance(oput, str):
                        load["out"] = oput
            if self.opts["cache_jobs"]:
                # Local job cache has been enabled
                salt.utils.minion.cache_jobs(self.opts, load["jid"], ret)

        load = {"cmd": ret_cmd, "load": list(jids.values())}

        def timeout_handler(*_):
            log.warning(
                "The minion failed to return the job information for job %s. "
                "This is often due to the master being shut down or "
                "overloaded. If the master is running, consider increasing "
                "the worker_threads value.",
                jid,
            )
            return True

        if sync:
            try:
                ret_val = self._send_req_sync(load, timeout=timeout)
            except SaltReqTimeoutError:
                timeout_handler()
                return ""
        else:
            with salt.ext.tornado.stack_context.ExceptionStackContext(timeout_handler):
                # pylint: disable=unexpected-keyword-arg
                ret_val = self._send_req_async(
                    load, timeout=timeout, callback=lambda f: None
                )
                # pylint: enable=unexpected-keyword-arg

        log.trace("ret_val = %s", ret_val)  # pylint: disable=no-member
        return ret_val

    def _state_run(self):
        """
        Execute a state run based on information set in the minion config file
        """
        if self.opts["startup_states"]:
            if (
                self.opts.get("master_type", "str") == "disable"
                and self.opts.get("file_client", "remote") == "remote"
            ):
                log.warning(
                    "Cannot run startup_states when 'master_type' is set "
                    "to 'disable' and 'file_client' is set to "
                    "'remote'. Skipping."
                )
            else:
                data = {"jid": "req", "ret": self.opts.get("ext_job_cache", "")}
                if self.opts["startup_states"] == "sls":
                    data["fun"] = "state.sls"
                    data["arg"] = [self.opts["sls_list"]]
                elif self.opts["startup_states"] == "top":
                    data["fun"] = "state.top"
                    data["arg"] = [self.opts["top_file"]]
                else:
                    data["fun"] = "state.highstate"
                    data["arg"] = []
                self.io_loop.add_callback(self._handle_decoded_payload, data)

    def _refresh_grains_watcher(self, refresh_interval_in_minutes):
        """
        Create a loop that will fire a pillar refresh to inform a master about a change in the grains of this minion
        :param refresh_interval_in_minutes:
        :return: None
        """
        if "__update_grains" not in self.opts.get("schedule", {}):
            if "schedule" not in self.opts:
                self.opts["schedule"] = {}
            self.opts["schedule"].update(
                {
                    "__update_grains": {
                        "function": "event.fire",
                        "args": [{}, "grains_refresh"],
                        "minutes": refresh_interval_in_minutes,
                    }
                }
            )

    @salt.ext.tornado.gen.coroutine
    def _fire_master_minion_start(self):
        include_grains = False
        if self.opts["start_event_grains"]:
            include_grains = True
        # Send an event to the master that the minion is live
        if self.opts["enable_legacy_startup_events"]:
            # Old style event. Defaults to False in 3001 release.
            yield self._fire_master_main(
                "Minion {} started at {}".format(self.opts["id"], time.asctime()),
                "minion_start",
                include_startup_grains=include_grains,
            )
        # send name spaced event
        yield self._fire_master_main(
            "Minion {} started at {}".format(self.opts["id"], time.asctime()),
            tagify([self.opts["id"], "start"], "minion"),
            include_startup_grains=include_grains,
        )

    def module_refresh(self, force_refresh=False, notify=False):
        """
        Refresh the functions and returners.
        """
        if not hasattr(self, "schedule"):
            return
        log.debug("Refreshing modules. Notify=%s", notify)
        self.functions, self.returners, _, self.executors = self._load_modules(
            force_refresh, notify=notify
        )

        self.schedule.functions = self.functions
        self.schedule.returners = self.returners

        self.beacons_refresh()

    def beacons_refresh(self):
        """
        Refresh the functions and returners.
        """
        if not self.beacons_leader:
            return
        log.debug("Refreshing beacons.")
        # Preserve the interval_map so beacon intervals aren't reset on refresh
        prev_interval_map = {}
        if hasattr(self, "beacons") and hasattr(self.beacons, "interval_map"):
            prev_interval_map = self.beacons.interval_map
        # Close existing beacon modules to release resources (e.g. inotify fds)
        # before replacing the Beacon instance.
        if hasattr(self, "beacons"):
            self.beacons.close_beacons()
        self.beacons = salt.beacons.Beacon(
            self.opts, self.functions, interval_map=prev_interval_map
        )

    def matchers_refresh(self):
        """
        Refresh the matchers
        """
        log.debug("Refreshing matchers.")
        self.matchers = salt.loader.matchers(self.opts)

    def pillar_schedule_refresh(self, current, new):
        """
        Refresh the schedule in pillar
        """
        # delete any pillar schedule items not
        # in the updated pillar values.
        for item in list(current):
            if item not in new:
                del current[item]

        # Update any entries that have changed
        pillar_schedule = {}
        for item in current:
            schedule_item = current[item]
            # ignore any of the internal keys
            ignore = [item for item in schedule_item if item.startswith("_")]
            if item in new:
                diff = salt.utils.dictdiffer.deep_diff(
                    schedule_item, new[item], ignore=ignore
                )
                if diff.get("new"):
                    pillar_schedule[item] = new[item]
                else:
                    pillar_schedule[item] = schedule_item

        # Add any new entries
        for item in new:
            if item not in pillar_schedule:
                pillar_schedule[item] = new[item]

        return pillar_schedule

    # TODO: only allow one future in flight at a time?
    @salt.ext.tornado.gen.coroutine
    def pillar_refresh(self, force_refresh=False, clean_cache=False):
        """
        Refresh the pillar
        """
        self.module_refresh(force_refresh)

        if self.connected:
            log.debug("Refreshing pillar.")
            async_pillar = salt.pillar.get_async_pillar(
                self.opts,
                self.opts["grains"],
                self.opts["id"],
                self.opts["saltenv"],
                pillarenv=self.opts.get("pillarenv"),
                clean_cache=clean_cache,
            )
            try:
                new_pillar = yield async_pillar.compile_pillar()
            except SaltClientError:
                # Do not exit if a pillar refresh fails.
                log.error(
                    "Pillar data could not be refreshed. "
                    "One or more masters may be down!"
                )
            else:
                current_schedule = self.opts["pillar"].get("schedule", {})
                new_schedule = new_pillar.get("schedule", {})
                new_pillar["schedule"] = self.pillar_schedule_refresh(
                    current_schedule, new_schedule
                )
                self.opts["pillar"] = new_pillar
            finally:
                async_pillar.destroy()
        self.matchers_refresh()
        self.beacons_refresh()
        with salt.utils.event.get_event(
            "minion", opts=self.opts, listen=False, io_loop=self.io_loop
        ) as evt:
            try:
                yield evt.fire_event_async(
                    {"complete": True},
                    tag=salt.defaults.events.MINION_PILLAR_REFRESH_COMPLETE,
                )
            except Exception as exc:  # pylint: disable=broad-except
                log.error("Error firing pillar refresh complete event: %s", exc)

    def manage_schedule(self, tag, data):
        """
        Refresh the functions and returners.
        """
        func = data.get("func", None)
        name = data.get("name", None)
        schedule = data.get("schedule", None)
        where = data.get("where", None)
        persist = data.get("persist", None)
        fire_event = data.get("fire_event", None)

        funcs = {
            "delete": ("delete_job", (name, persist)),
            "add": ("add_job", (schedule, persist)),
            "modify": ("modify_job", (name, schedule, persist)),
            "enable": ("enable_schedule", (persist,)),
            "disable": ("disable_schedule", (persist,)),
            "enable_job": ("enable_job", (name, persist)),
            "run_job": ("run_job", (name,)),
            "disable_job": ("disable_job", (name, persist)),
            "postpone_job": ("postpone_job", (name, data)),
            "skip_job": ("skip_job", (name, data)),
            "reload": ("reload", (schedule,)),
            "list": ("list", (where,)),
            "save_schedule": ("save_schedule", ()),
            "get_next_fire_time": ("get_next_fire_time", (name,)),
            "job_status": ("job_status", (name, fire_event)),
        }

        # Call the appropriate schedule function
        try:
            alias, params = funcs.get(func)
            getattr(self.schedule, alias)(*params)
        except TypeError:
            log.error('Function "%s" is unavailable in salt.utils.scheduler', func)

    def manage_beacons(self, tag, data):
        """
        Manage Beacons
        """
        if not self.beacons_leader:
            return

        func = data.get("func", None)
        name = data.get("name", None)
        beacon_data = data.get("beacon_data", None)
        include_pillar = data.get("include_pillar", None)
        include_opts = data.get("include_opts", None)

        funcs = {
            "add": ("add_beacon", {"name": name, "beacon_data": beacon_data}),
            "modify": ("modify_beacon", {"name": name, "beacon_data": beacon_data}),
            "delete": ("delete_beacon", {"name": name}),
            "enable": ("enable_beacons", {}),
            "disable": ("disable_beacons", {}),
            "enable_beacon": ("enable_beacon", {"name": name}),
            "disable_beacon": ("disable_beacon", {"name": name}),
            "list": (
                "list_beacons",
                {"include_opts": include_opts, "include_pillar": include_pillar},
            ),
            "list_available": ("list_available_beacons", {}),
            "validate_beacon": (
                "validate_beacon",
                {"name": name, "beacon_data": beacon_data},
            ),
            "reset": ("reset", {}),
        }

        # Call the appropriate beacon function
        try:
            alias, params = funcs.get(func)
            getattr(self.beacons, alias)(**params)
        except TypeError:
            log.error('Function "%s" is unavailable in salt.utils.beacons', func)

    def environ_setenv(self, tag, data):
        """
        Set the salt-minion main process environment according to
        the data contained in the minion event data
        """
        environ = data.get("environ", None)
        if environ is None:
            return False
        false_unsets = data.get("false_unsets", False)
        clear_all = data.get("clear_all", False)
        import salt.modules.environ as mod_environ

        return mod_environ.setenv(environ, false_unsets, clear_all)

    def _pre_tune(self):
        """
        Set the minion running flag and issue the appropriate warnings if
        the minion cannot be started or is already running
        """
        if self._running is None:
            self._running = True
        elif self._running is False:
            log.error(
                "This %s was scheduled to stop. Not running %s.tune_in()",
                self.__class__.__name__,
                self.__class__.__name__,
            )
            return
        elif self._running is True:
            log.error(
                "This %s is already running. Not running %s.tune_in()",
                self.__class__.__name__,
                self.__class__.__name__,
            )
            return

        try:
            log.info(
                "%s is starting as user '%s'",
                self.__class__.__name__,
                salt.utils.user.get_user(),
            )
        except Exception as err:  # pylint: disable=broad-except
            # Only windows is allowed to fail here. See #3189. Log as debug in
            # that case. Else, error.
            log.log(
                salt.utils.platform.is_windows() and logging.DEBUG or logging.ERROR,
                "Failed to get the user who is starting %s",
                self.__class__.__name__,
                exc_info=err,
            )

    def _mine_send(self, tag, data):
        """
        Send mine data to the master
        """
        # Consider using a long-running req channel to send mine data
        with salt.channel.client.ReqChannel.factory(self.opts) as channel:
            data["tok"] = self.tok
            try:
                ret = channel.send(
                    data,
                    timeout=self._return_retry_timer(),
                    tries=self.opts["return_retry_tries"],
                )
                return ret
            except SaltReqTimeoutError:
                log.warning("Unable to send mine data to master.")
                return None

    @salt.ext.tornado.gen.coroutine
    def handle_event(self, package):
        """
        Handle an event from the epull_sock (all local minion events)
        """
        if not self.ready:
            raise salt.ext.tornado.gen.Return()
        tag, data = salt.utils.event.SaltEvent.unpack(package)

        if "proxy_target" in data and self.opts.get("metaproxy") == "deltaproxy":
            proxy_target = data["proxy_target"]
            if proxy_target not in self.deltaproxy_objs:
                raise salt.ext.tornado.gen.Return()
            _minion = self.deltaproxy_objs[proxy_target]
        else:
            _minion = self

        log.debug("Minion of '%s' is handling event tag '%s'", self.opts["master"], tag)
        if tag.startswith("module_refresh"):
            _minion.module_refresh(
                force_refresh=data.get("force_refresh", False),
                notify=data.get("notify", False),
            )
        elif tag.startswith("__master_req_channel_payload"):
            request_id, job_master = tag.rsplit("/", 2)[1:]
            if job_master == self.opts["master"]:
                ret = None
                try:
                    ret = yield _minion.req_channel.send(
                        data,
                        timeout=_minion._return_retry_timer(),
                        tries=_minion.opts["return_retry_tries"],
                    )
                except salt.exceptions.SaltReqTimeoutError:
                    log.error(
                        "Timeout encountered while sending %r request. id=%s",
                        data,
                        request_id,
                    )
                    with salt.utils.event.get_event(
                        "minion", opts=self.opts, listen=False, io_loop=self.io_loop
                    ) as event:
                        try:
                            yield event.fire_event_async(
                                {"ret": None, "error": "timeout"},
                                f"__master_req_channel_return/{request_id}",
                            )
                        except Exception as exc:  # pylint: disable=broad-except
                            log.error(
                                "Error firing master request timeout event: %s", exc
                            )
                    raise salt.ext.tornado.gen.Return()
                with salt.utils.event.get_event(
                    "minion", opts=self.opts, listen=False, io_loop=self.io_loop
                ) as event:
                    try:
                        yield event.fire_event_async(
                            {"ret": ret},
                            f"__master_req_channel_return/{request_id}",
                        )
                    except Exception as exc:  # pylint: disable=broad-except
                        log.error("Error firing master request return event: %s", exc)
            else:
                log.debug(
                    "Skipping req for other master: cmd=%s master=%s id=%s",
                    data["cmd"],
                    job_master,
                    request_id,
                )
        elif tag.startswith("pillar_refresh"):
            yield _minion.pillar_refresh(
                force_refresh=data.get("force_refresh", False),
                clean_cache=data.get("clean_cache", False),
            )
        elif tag.startswith("beacons_refresh"):
            _minion.beacons_refresh()
        elif tag.startswith("matchers_refresh"):
            _minion.matchers_refresh()
        elif tag.startswith("manage_schedule"):
            _minion.manage_schedule(tag, data)
        elif tag.startswith("manage_beacons"):
            _minion.manage_beacons(tag, data)
        elif tag.startswith("grains_refresh"):
            if (
                data.get("force_refresh", False)
                or _minion.grains_cache != _minion.opts["grains"]
            ):
                yield _minion.pillar_refresh(force_refresh=True)
                _minion.grains_cache = _minion.opts["grains"]
        elif tag.startswith("environ_setenv"):
            self.environ_setenv(tag, data)
        elif tag.startswith("_minion_mine"):
            self._mine_send(tag, data)
        elif tag.startswith("fire_master"):
            if self.connected:
                log.debug(
                    "Forwarding event %s to master %s",
                    data["tag"],
                    self.opts["master"],
                )
                yield self._fire_master_main(
                    data["data"],
                    data["tag"],
                    data["events"],
                    data["pretag"],
                )
            else:
                log.debug(
                    "Master %s is not connected, dropping event %s",
                    self.opts["master"],
                    data["tag"],
                )
        elif tag.startswith(master_event(type="disconnected")) or tag.startswith(
            master_event(type="failback")
        ):
            # if the master disconnect event is for a different master, raise an exception
            if (
                tag.startswith(master_event(type="disconnected"))
                and data["master"] != self.opts["master"]
            ):
                # not mine master, ignore
                raise salt.ext.tornado.gen.Return()
            if tag.startswith(master_event(type="failback")):
                # if the master failback event is not for the top master, raise an exception
                if data["master"] != self.opts["master_list"][0]:
                    raise SaltException(
                        "Bad master '{}' when mine failback is '{}'".format(
                            data["master"], self.opts["master"]
                        )
                    )
                # if the master failback event is for the current master, raise an exception
                elif data["master"] == self.opts["master"][0]:
                    raise SaltException(
                        "Already connected to '{}'".format(data["master"])
                    )

            if self.connected:
                # we are not connected anymore
                self.connected = False
                log.info("Connection to master %s lost", self.opts["master"])
                if self.opts["transport"] != "tcp":
                    self.schedule.delete_job(name=master_event(type="alive"))

                log.info("Trying to tune in to next master from master-list")

                if hasattr(self, "pub_channel"):
                    self.pub_channel.on_recv(None)
                    if hasattr(self.pub_channel, "auth"):
                        self.pub_channel.auth.invalidate()
                    if hasattr(self.pub_channel, "close"):
                        self.pub_channel.close()
                if hasattr(self, "req_channel") and self.req_channel:
                    yield self.req_channel.close_async()
                    yield salt.ext.tornado.gen.sleep(0)
                    self.req_channel = None

                # if eval_master finds a new master for us, self.connected
                # will be True again on successful master authentication
                try:
                    master, self.pub_channel = yield self.eval_master(
                        opts=self.opts,
                        failed=True,
                        failback=tag.startswith(master_event(type="failback")),
                    )
                except SaltClientError:
                    pass

                if self.connected:
                    self.opts["master"] = master

                    # re-init the subsystems to work with the new master
                    log.info(
                        "Re-initialising subsystems for new master %s",
                        self.opts["master"],
                    )

                    self.req_channel = salt.channel.client.AsyncReqChannel.factory(
                        self.opts, io_loop=self.io_loop
                    )
                    yield self.req_channel.connect()

                    # put the current schedule into the new loaders
                    self.opts["schedule"] = self.schedule.option("schedule")
                    (
                        self.functions,
                        self.returners,
                        self.function_errors,
                        self.executors,
                    ) = self._load_modules()
                    # make the schedule to use the new 'functions' loader
                    self.schedule.functions = self.functions
                    self.pub_channel.on_recv(self._handle_payload)
                    yield self._fire_master_minion_start()
                    log.info("Minion is ready to receive requests!")

                    # update scheduled job to run with the new master addr
                    if self.opts["transport"] != "tcp":
                        schedule = {
                            "function": "status.master",
                            "seconds": self.opts["master_alive_interval"],
                            "jid_include": True,
                            "maxrunning": 1,
                            "return_job": False,
                            "kwargs": {
                                "master": self.opts["master"],
                                "connected": True,
                            },
                        }
                        self.schedule.modify_job(
                            name=master_event(type="alive", master=self.opts["master"]),
                            schedule=schedule,
                        )

                        if self.opts["master_failback"] and "master_list" in self.opts:
                            if self.opts["master"] != self.opts["master_list"][0]:
                                schedule = {
                                    "function": "status.ping_master",
                                    "seconds": self.opts["master_failback_interval"],
                                    "jid_include": True,
                                    "maxrunning": 1,
                                    "return_job": False,
                                    "kwargs": {"master": self.opts["master_list"][0]},
                                }
                                self.schedule.modify_job(
                                    name=master_event(type="failback"),
                                    schedule=schedule,
                                )
                            else:
                                self.schedule.delete_job(
                                    name=master_event(type="failback"), persist=True
                                )
                else:
                    self.restart = True
                    self.io_loop.stop()

        elif tag.startswith(master_event(type="connected")):
            # handle this event only once. otherwise it will pollute the log
            # also if master type is failover all the reconnection work is done
            # by `disconnected` event handler and this event must never happen,
            # anyway check it to be sure
            if not self.connected and self.opts["master_type"] != "failover":
                log.info("Connection to master %s re-established", self.opts["master"])
                self.connected = True
                # modify the __master_alive job to only fire,
                # if the connection is lost again
                if self.opts["transport"] != "tcp":
                    schedule = {
                        "function": "status.master",
                        "seconds": self.opts["master_alive_interval"],
                        "jid_include": True,
                        "maxrunning": 1,
                        "return_job": False,
                        "kwargs": {"master": self.opts["master"], "connected": True},
                    }

                    self.schedule.modify_job(
                        name=master_event(type="alive", master=self.opts["master"]),
                        schedule=schedule,
                    )
        elif tag.startswith("__schedule_return"):
            # reporting current connection with master
            if data["schedule"].startswith(master_event(type="alive", master="")):
                if data["return"]:
                    log.debug(
                        "Connected to master %s",
                        data["schedule"].split(master_event(type="alive", master=""))[
                            1
                        ],
                    )
            yield self._return_pub_main(data, ret_cmd="_return")
        elif tag.startswith("_salt_error"):
            if self.connected:
                log.debug("Forwarding salt error event tag=%s", tag)
                yield self._fire_master_main(data, tag)
        elif tag.startswith("salt/auth/creds"):
            key = tuple(data["key"])
            log.debug(
                "Updating auth data for %s: %s -> %s",
                key,
                salt.crypt.AsyncAuth.creds_map.get(key),
                data["creds"],
            )
            salt.crypt.AsyncAuth.creds_map[tuple(data["key"])] = data["creds"]
        elif tag.startswith("__beacons_return"):
            if self.connected:
                log.debug("Firing beacons to master")
                yield self._fire_master_main(events=data["beacons"])

    def cleanup_subprocesses(self):
        """
        Clean up subprocesses and spawned threads.
        """
        # Add an extra fallback in case a forked process leaks through
        multiprocessing.active_children()
        self.subprocess_list.cleanup()
        if self.schedule:
            self.schedule.cleanup_subprocesses()

    def _setup_core(self):
        """
        Set up the core minion attributes.
        This is safe to call multiple times.
        """
        if not self.ready:
            # First call. Initialize.
            (
                self.functions,
                self.returners,
                self.function_errors,
                self.executors,
            ) = self._load_modules()
            self.mod_opts = self._prep_mod_opts()
            #            self.matcher = Matcher(self.opts, self.functions)
            self.matchers = salt.loader.matchers(self.opts)
            if self.beacons_leader:
                self.beacons = salt.beacons.Beacon(self.opts, self.functions)
            uid = salt.utils.user.get_uid(user=self.opts.get("user", None))
            self.proc_dir = get_proc_dir(self.opts["cachedir"], uid=uid)
            self.grains_cache = self.opts["grains"]
            self.ready = True

    def setup_beacons(self, before_connect=False):
        """
        Set up the beacons.
        This is safe to call multiple times.
        """
        # In multimaster configuration the only one minion shall execute beacons
        if not self.beacons_leader:
            return

        self._setup_core()
        loop_interval = self.opts["loop_interval"]
        if "beacons" not in self.periodic_callbacks:
            self.beacons = salt.beacons.Beacon(self.opts, self.functions)

            def handle_beacons():
                # Process Beacons
                beacons = None
                try:
                    beacons = self.process_beacons(self.functions)
                except Exception:  # pylint: disable=broad-except
                    log.critical("The beacon errored: ", exc_info=True)
                if beacons:
                    with salt.utils.event.get_event(
                        "minion",
                        opts=self.opts,
                        listen=False,
                    ) as event:
                        event.fire_event({"beacons": beacons}, "__beacons_return")

            if before_connect:
                # Make sure there is a chance for one iteration to occur before connect
                handle_beacons()

            self.add_periodic_callback("beacons", handle_beacons)

    def setup_scheduler(self, before_connect=False):
        """
        Set up the scheduler.
        This is safe to call multiple times.
        """
        self._setup_core()

        loop_interval = self.opts["loop_interval"]

        if "schedule" not in self.periodic_callbacks:
            if "schedule" not in self.opts:
                self.opts["schedule"] = {}
            if not hasattr(self, "schedule"):
                self.schedule = salt.utils.schedule.Schedule(
                    self.opts,
                    self.functions,
                    self.returners,
                    utils=self.utils,
                    cleanup=[master_event(type="alive")],
                )

            try:
                if self.opts["grains_refresh_every"]:  # In minutes, not seconds!
                    log.debug(
                        "Enabling the grains refresher. Will run every %d minute(s).",
                        self.opts["grains_refresh_every"],
                    )
                    self._refresh_grains_watcher(abs(self.opts["grains_refresh_every"]))
            except Exception as exc:  # pylint: disable=broad-except
                log.error(
                    "Exception occurred in attempt to initialize grain refresh "
                    "routine during minion tune-in: %s",
                    exc,
                )

            # TODO: actually listen to the return and change period
            def handle_schedule():
                self.process_schedule(self, loop_interval)

            if before_connect:
                # Make sure there is a chance for one iteration to occur before connect
                handle_schedule()

            self.add_periodic_callback("schedule", handle_schedule)

    def setup_state_queue_processing(self):
        """
        Set up the state queue processing.
        This is safe to call multiple times.
        """
        if "state_queue" not in self.periodic_callbacks:
            # We add the periodic callback directly. The callback itself handles
            # threading to avoid blocking the loop.
            self.add_periodic_callback(
                "state_queue", self.process_state_queue, interval=0.3
            )

    def process_state_queue(self):
        """
        Check the state queue for pending jobs and execute them if safe.
        Runs as an async task on the main loop.
        """
        if getattr(self, "_state_queue_processing_active", False):
            return

        self._state_queue_processing_active = True
        self.io_loop.spawn_callback(self._process_state_queue_async)

    @salt.ext.tornado.gen.coroutine
    def _process_state_queue_async(self):
        """
        Async body of process_state_queue.
        """
        yield self._process_state_queue_async_impl()

    async def _process_state_queue_async_impl(self):
        try:
            queue_dir = salt.utils.state.state_queue_dir(self.opts)
            if not os.path.exists(queue_dir):
                return

            # Acquire lock to check queue
            try:
                async with salt.utils.state.acquire_async_queue_lock(self.opts):
                    # Check for queued jobs
                    files = []
                    try:
                        for fn in os.listdir(queue_dir):
                            if fn.startswith("queued_") and fn.endswith(".p"):
                                files.append(fn)
                    except OSError:
                        pass

                    if not files:
                        return

                    # Sort by JID to ensure we process in the order expected by the state system's
                    # dependency check (_prior_running_states), which relies on JID comparison.
                    # Filename: queued_<timestamp>_<jid>.p
                    def sort_key(fn):
                        try:
                            # Extract JID part (after second underscore, before .p)
                            parts = fn.split("_")
                            if len(parts) >= 3:
                                # state.py uses parts[2] as the JID. We should match this to ensure
                                # consistent sorting, even if the filename has extra underscores.
                                jid_str = parts[2]
                                if jid_str.endswith(".p"):
                                    jid_str = jid_str[:-2]
                                return int(jid_str)
                        except (ValueError, IndexError):
                            pass
                        return float("inf")

                    files.sort(key=sort_key)

                    # Pick the candidate to check for conflicts
                    candidate_fn = files[0]
                    candidate_jid = None
                    try:
                        parts = candidate_fn.split("_")
                        if len(parts) >= 3:
                            jid_str = parts[2]
                            if jid_str.endswith(".p"):
                                jid_str = jid_str[:-2]
                            candidate_jid = int(jid_str)
                    except (ValueError, IndexError):
                        pass

                    log.trace(
                        "State queue processing: found %d queued files in %s, candidate: %s",
                        len(files),
                        queue_dir,
                        candidate_fn,
                    )

                    # Check if this candidate is blocked by any active jobs
                    # Use get_active_states to ensure we see jobs even if they share our PID (placeholder)
                    try:
                        active = salt.utils.state.get_active_states(self.opts)
                    except OSError as exc:
                        log.error(
                            "State queue processing: System resource exhaustion preventing active job check (%s). Waiting.",
                            exc,
                        )
                        return

                    # Use the shared utility logic to determine if we should run
                    blocking_jobs = salt.utils.state.check_prior_running_states(
                        self.opts, candidate_jid, active
                    )

                    if blocking_jobs:
                        log.debug(
                            "State queue processing: candidate job %s is blocked by active jobs: %s. Waiting.",
                            candidate_jid,
                            [j["jid"] for j in blocking_jobs],
                        )
                        return

                    # Pick oldest
                    fn = files[0]
                    path = os.path.join(queue_dir, fn)

                    try:
                        with salt.utils.files.fopen(path, "rb") as fp_:
                            data = salt.payload.load(fp_)
                    except (OSError, ValueError) as exc:
                        # If we can't open the file due to resource limits, we MUST NOT delete it.
                        if isinstance(exc, OSError) and exc.errno in (
                            errno.EMFILE,
                            errno.ENFILE,
                        ):
                            log.error(
                                "State queue processing: Too many open files, cannot read queued job %s. Waiting.",
                                fn,
                            )
                            return

                        # Corrupt or unreadable?
                        log.error("Failed to load queued job %s, removing.", fn)
                        try:
                            os.remove(path)
                        except OSError:
                            pass
                        return

                    # Extract JID from filename to ensure the execution JID matches the
                    # queuing JID used for ordering. Ideally these would match in the
                    # payload, but state.py generates a new JID for the payload while
                    # using the original JID for the filename. This mismatch causes
                    # the loop (Running New > Queued Old).
                    try:
                        parts = fn.split("_")
                        if len(parts) >= 3:
                            jid_str = parts[2]
                            if jid_str.endswith(".p"):
                                jid_str = jid_str[:-2]
                            # Verify it's an int before using it
                            int(jid_str)
                            data["jid"] = jid_str
                            log.info(
                                "Updated execution JID to match queued filename: %s",
                                jid_str,
                            )
                    except (ValueError, IndexError):
                        pass

                    # Execute
                    log.info(
                        "Popping queued job %s from the queue for execution",
                        data.get("jid"),
                    )

                    # Rename file to running_ to close the invisible gap
                    running_fn = fn.replace("queued_", "running_", 1)
                    running_path = os.path.join(queue_dir, running_fn)
                    try:
                        os.rename(path, running_path)
                        data["_state_queue_file"] = running_path
                    except OSError as exc:
                        log.error("Failed to rename queued job file %s: %s", path, exc)
                        return

                    # Mark job to bypass process_count_max checks since it has already waited
                    # its turn in the State queue and we don't want it to starve.
                    data["__ignore_process_count_max"] = True

                    if hasattr(self, "io_loop"):
                        self.io_loop.spawn_callback(self._handle_decoded_payload, data)
                    else:
                        # Fallback if io_loop is not explicit (should not happen in Minion)
                        self.io_loop.spawn_callback(self._handle_decoded_payload, data)

            except (OSError, salt.exceptions.FileLockError) as exc:
                if isinstance(exc, salt.exceptions.FileLockError) or (
                    isinstance(exc, OSError)
                    and exc.errno in (errno.EMFILE, errno.ENFILE)
                ):
                    log.error(
                        "State queue processing: Unable to acquire queue lock due to system resource exhaustion (%s). Waiting.",
                        exc,
                    )
                    return
                # Re-raise other errors
                raise

        except Exception:  # pylint: disable=broad-exception-caught
            log.critical("State queue processing failed", exc_info=True)
        finally:
            self._state_queue_processing_active = False

    def add_periodic_callback(self, name, method, interval=1):
        """
        Add a periodic callback to the event loop and call its start method.
        If a callback by the given name exists this method returns False
        """
        if name in self.periodic_callbacks:
            return False
        self.periodic_callbacks[name] = salt.ext.tornado.ioloop.PeriodicCallback(
            method,
            interval * 1000,
        )
        self.periodic_callbacks[name].start()
        return True

    def remove_periodic_callback(self, name):
        """
        Remove a periodic callback.
        If a callback by the given name does not exist this method returns False
        """
        callback = self.periodic_callbacks.pop(name, None)
        if callback is None:
            return False
        callback.stop()
        return True

    # Main Minion Tune In
    def tune_in(self, start=True):
        """
        Lock onto the publisher. This is the main event loop for the minion
        :rtype : None
        """
        self._pre_tune()

        log.debug("Minion '%s' trying to tune in", self.opts["id"])

        if start:
            if self.opts.get("beacons_before_connect", False):
                self.setup_beacons(before_connect=True)
            if self.opts.get("scheduler_before_connect", False):
                self.setup_scheduler(before_connect=True)
            self.sync_connect_master()
        if self.connected:
            self.io_loop.add_callback(self._fire_master_minion_start)
            log.info("Minion is ready to receive requests!")

        # Make sure to gracefully handle SIGUSR1
        enable_sigusr1_handler()

        # Make sure to gracefully handle CTRL_LOGOFF_EVENT
        if HAS_WIN_FUNCTIONS:
            salt.utils.win_functions.enable_ctrl_logoff_handler()

        # On first startup execute a state run if configured to do so
        self._state_run()

        self.setup_beacons()
        self.setup_scheduler()
        self.setup_state_queue_processing()
        self.setup_process_queue_processing()
        self.add_periodic_callback("cleanup", self.cleanup_subprocesses)

        # schedule the stuff that runs every interval
        ping_interval = self.opts.get("ping_interval", 0) * 60
        if ping_interval > 0 and self.connected:

            def ping_master():
                try:

                    def ping_timeout_handler(*_):
                        if self.opts.get("auth_safemode", False):
                            log.error(
                                "** Master Ping failed. Attempting to restart minion**"
                            )
                            delay = self.opts.get("random_reauth_delay", 5)
                            log.info("delaying random_reauth_delay %ss", delay)
                            try:
                                self.functions["service.restart"](service_name())
                            except KeyError:
                                # Probably no init system (running in docker?)
                                log.warning(
                                    "ping_interval reached without response "
                                    "from the master, but service.restart "
                                    "could not be run to restart the minion "
                                    "daemon. ping_interval requires that the "
                                    "minion is running under an init system."
                                )

                    self.io_loop.add_callback(
                        self._fire_master_main,
                        "ping",
                        "minion_ping",
                        timeout_handler=ping_timeout_handler,
                    )
                except Exception:  # pylint: disable=broad-except
                    log.warning(
                        "Attempt to ping master failed.", exc_on_loglevel=logging.DEBUG
                    )

            self.remove_periodic_callback("ping")
            self.add_periodic_callback("ping", ping_master, ping_interval)

        # add handler to subscriber
        if hasattr(self, "pub_channel") and self.pub_channel is not None:
            self.pub_channel.on_recv(self._handle_payload)
        elif self.opts.get("master_type") != "disable":
            log.error("No connection to master found. Scheduled jobs will not run.")

        # Periodic full-generation gc.collect() to reap reference cycles
        # created by Tornado coroutine timeouts (FutureWithTimeout,
        # Runner.handle_yield closures, traceback objects, etc.).  Python's
        # default GC thresholds (700, 10, 10) run generation-2 too rarely
        # for the rate these cycles accumulate in a busy minion (~50 MB/hr
        # of cyclic garbage measured under stress).  Reaping every 60 s
        # keeps the working set steady.
        self.add_periodic_callback("gc_collect", gc.collect, interval=60)

        if start:
            try:
                self.io_loop.start()
                if self.restart:
                    self.destroy()
            except (
                KeyboardInterrupt,
                RuntimeError,
            ):  # A RuntimeError can be re-raised by Tornado on shutdown
                self.destroy()

    def _handle_payload(self, payload):
        if payload is not None and payload["enc"] == "aes":
            if self._target_load(payload["load"]):
                self.io_loop.spawn_callback(
                    self._handle_decoded_payload, payload["load"]
                )
            elif self.opts["zmq_filtering"]:
                # In the filtering enabled case, we'd like to know when minion sees something it shouldn't
                log.trace(
                    "Broadcast message received not for this minion, Load: %s",
                    payload["load"],
                )
        # If it's not AES, and thus has not been verified, we do nothing.
        # In the future, we could add support for some clearfuncs, but
        # the minion currently has no need.

    def _target_load(self, load):
        # Verify that the publication is valid
        if (
            "tgt" not in load
            or "jid" not in load
            or "fun" not in load
            or "arg" not in load
        ):
            return False
        # Verify that the publication applies to this minion

        # It's important to note that the master does some pre-processing
        # to determine which minions to send a request to. So for example,
        # a "salt -G 'grain_key:grain_val' test.ping" will invoke some
        # pre-processing on the master and this minion should not see the
        # publication if the master does not determine that it should.

        if "tgt_type" in load:
            match_func = self.matchers.get(
                "{}_match.match".format(load["tgt_type"]), None
            )
            if match_func is None:
                return False
            if load["tgt_type"] in ("grain", "grain_pcre", "pillar"):
                delimiter = load.get("delimiter", DEFAULT_TARGET_DELIM)
                if not match_func(load["tgt"], delimiter=delimiter):
                    return False
            elif not match_func(load["tgt"]):
                return False
        else:
            if not self.matchers["glob_match.match"](load["tgt"]):
                return False

        return True

    @salt.ext.tornado.gen.coroutine
    def destroy_async(self):
        """
        Async teardown for use on the minion I/O loop. Ensures REQ transport
        ``close_async`` completes before the next connect attempt (see ``connect_master``).
        """
        self._running = False
        if hasattr(self, "process_manager") and self.process_manager is not None:
            self.process_manager.stop_restarting()
            self.process_manager.kill_children()
        if hasattr(self, "schedule"):
            del self.schedule
        if hasattr(self, "pub_channel") and self.pub_channel is not None:
            self.pub_channel.on_recv(None)
            self.pub_channel.close()
            self.pub_channel = None
        if hasattr(self, "req_channel") and self.req_channel is not None:
            yield self.req_channel.close_async()
            yield salt.ext.tornado.gen.sleep(0)
            self.req_channel = None
        if hasattr(self, "periodic_callbacks"):
            for cb in self.periodic_callbacks.values():
                cb.stop()

    def destroy(self):
        """
        Tear down the minion
        """
        self._running = False
        if hasattr(self, "process_manager") and self.process_manager is not None:
            self.process_manager.stop_restarting()
            self.process_manager.kill_children()
        if hasattr(self, "schedule"):
            del self.schedule
        if hasattr(self, "pub_channel") and self.pub_channel is not None:
            self.pub_channel.on_recv(None)
            self.pub_channel.close()
        if hasattr(self, "req_channel") and self.req_channel is not None:
            self.req_channel.close()
        if hasattr(self, "periodic_callbacks"):
            for cb in self.periodic_callbacks.values():
                cb.stop()

        # Clean up loaders
        if hasattr(self, "functions") and self.functions is not None:
            if hasattr(self.functions, "destroy"):
                self.functions.destroy()
            self.functions = {}
        if hasattr(self, "returners") and self.returners is not None:
            if hasattr(self.returners, "destroy"):
                self.returners.destroy()
            self.returners = {}
        if hasattr(self, "states") and self.states is not None:
            if hasattr(self.states, "destroy"):
                self.states.destroy()
            self.states = {}
        if hasattr(self, "rend") and self.rend is not None:
            if hasattr(self.rend, "destroy"):
                self.rend.destroy()
            self.rend = {}
        if hasattr(self, "matchers") and self.matchers is not None:
            if hasattr(self.matchers, "destroy"):
                self.matchers.destroy()
            self.matchers = {}
        if hasattr(self, "executors") and self.executors is not None:
            if hasattr(self.executors, "destroy"):
                self.executors.destroy()
            self.executors = {}
        if hasattr(self, "utils") and self.utils is not None:
            if hasattr(self.utils, "destroy"):
                self.utils.destroy()
            self.utils = {}

    # pylint: disable=W1701
    def __del__(self):
        self.destroy()

    # pylint: enable=W1701


class Syndic(Minion):
    """
    Make a Syndic minion, this minion will use the minion keys on the
    master to authenticate with a higher level master.
    """

    def __init__(self, opts, **kwargs):
        self.local = None
        self.forward_events = None
        self._syndic_interface = opts.get("interface")
        self._syndic = True
        # force auth_safemode True because Syndic don't support autorestart
        opts["auth_safemode"] = True
        opts["loop_interval"] = 1
        super().__init__(opts, **kwargs)
        self.mminion = salt.minion.MasterMinion(opts)
        self.jid_forward_cache = set()
        self.jids = {}
        self.raw_events = []
        self.pub_future = None

    def _handle_decoded_payload(self, data):
        """
        Override this method if you wish to handle the decoded data
        differently.
        """
        # TODO: even do this??
        data["to"] = int(data.get("to", self.opts["timeout"])) - 1
        # Only forward the command if it didn't originate from ourselves
        if data.get("master_id", 0) != self.opts.get("master_id", 1):
            self.syndic_cmd(data)

    def syndic_cmd(self, data):
        """
        Take the now clear load and forward it on to the client cmd
        """
        # Set up default tgt_type
        if "tgt_type" not in data:
            data["tgt_type"] = "glob"

        kwargs = {"auth_list": data.pop("auth_list", [])}

        # optionally add a few fields to the publish data
        for field in (
            "master_id",  # which master the job came from
            "user",  # which user ran the job
        ):
            if field in data:
                kwargs[field] = data[field]

        def timeout_handler(*args):
            log.warning("Unable to forward pub data: %s", args[1])
            return True

        with salt.ext.tornado.stack_context.ExceptionStackContext(timeout_handler):
            self.local.pub_async(
                data["tgt"],
                data["fun"],
                data["arg"],
                data["tgt_type"],
                data["ret"],
                data["jid"],
                data["to"],
                io_loop=self.io_loop,
                callback=lambda _: None,
                **kwargs,
            )

    def _send_req_sync(self, load, timeout):
        return self.req_channel.send(
            load, timeout=timeout, tries=self.opts["return_retry_tries"]
        )

    @salt.ext.tornado.gen.coroutine
    def _send_req_async(self, load, timeout):
        ret = yield self.async_req_channel.send(
            load, timeout=timeout, tries=self.opts["return_retry_tries"]
        )
        return ret

    def fire_master_syndic_start(self):
        # Send an event to the master that the minion is live
        if self.opts["enable_legacy_startup_events"]:
            # Old style event. Defaults to false in 3001 release.
            self._fire_master(
                "Syndic {} started at {}".format(self.opts["id"], time.asctime()),
                "syndic_start",
            )
        self._fire_master(
            "Syndic {} started at {}".format(self.opts["id"], time.asctime()),
            tagify([self.opts["id"], "start"], "syndic"),
        )

    # TODO: clean up docs
    def tune_in_no_block(self):
        """
        Executes the tune_in sequence but omits extra logging and the
        management of the event bus assuming that these are handled outside
        the tune_in sequence
        """
        # Instantiate the local client
        self.local = salt.client.get_local_client(
            self.opts["_minion_conf_file"], io_loop=self.io_loop
        )

        # add handler to subscriber
        self.pub_channel.on_recv(self._process_cmd_socket)
        self.req_channel = salt.channel.client.ReqChannel.factory(self.opts)
        self.async_req_channel = salt.channel.client.AsyncReqChannel.factory(self.opts)

    def _process_cmd_socket(self, payload):
        if payload is not None and payload["enc"] == "aes":
            log.trace("Handling payload")
            self._handle_decoded_payload(payload["load"])
        # If it's not AES, and thus has not been verified, we do nothing.
        # In the future, we could add support for some clearfuncs, but
        # the syndic currently has no need.

    @salt.ext.tornado.gen.coroutine
    def reconnect(self):
        if hasattr(self, "pub_channel"):
            self.pub_channel.on_recv(None)
            if hasattr(self.pub_channel, "close"):
                self.pub_channel.close()
            del self.pub_channel

        # if eval_master finds a new master for us, self.connected
        # will be True again on successful master authentication
        master, self.pub_channel = yield self.eval_master(opts=self.opts)

        if self.connected:
            self.opts["master"] = master
            self.pub_channel.on_recv(self._process_cmd_socket)
            log.info("Minion is ready to receive requests!")

        raise salt.ext.tornado.gen.Return(self)

    @salt.ext.tornado.gen.coroutine
    def destroy_async(self):
        """
        Async teardown on the I/O loop (see :meth:`Minion.destroy_async`).
        """
        yield Minion.destroy_async(self)
        if self.local is not None:
            self.local.destroy()
            self.local = None

        if self.forward_events is not None:
            self.forward_events.stop()
            self.forward_events = None

    def destroy(self):
        """
        Tear down the syndic minion
        """
        # We borrowed the local clients poller so give it back before
        # it's destroyed. Reset the local poller reference.
        super().destroy()
        if self.local is not None:
            self.local.destroy()
            self.local = None
        if hasattr(self, "mminion") and self.mminion is not None:
            self.mminion.destroy()
            self.mminion = None

        if self.forward_events is not None:
            self.forward_events.stop()
            self.forward_events = None


# TODO: need a way of knowing if the syndic connection is busted
class SyndicManager(MinionBase):
    """
    Make a MultiMaster syndic minion, this minion will handle relaying jobs and returns from
    all minions connected to it to the list of masters it is connected to.

    Modes (controlled by `syndic_mode`:
        sync: This mode will synchronize all events and publishes from higher level masters
        cluster: This mode will only sync job publishes and returns

    Note: jobs will be returned best-effort to the requesting master. This also means
    (since we are using zmq) that if a job was fired and the master disconnects
    between the publish and return, that the return will end up in a zmq buffer
    in this Syndic headed to that original master.

    In addition, since these classes all seem to use a mix of blocking and non-blocking
    calls (with varying timeouts along the way) this daemon does not handle failure well,
    it will (under most circumstances) stall the daemon for ~15s trying to forward events
    to the down master
    """

    # time to connect to upstream master
    SYNDIC_CONNECT_TIMEOUT = 5
    SYNDIC_EVENT_TIMEOUT = 5

    def __init__(self, opts, io_loop=None):
        opts["loop_interval"] = 1
        super().__init__(opts)
        self._closing = False
        self.mminion = salt.minion.MasterMinion(opts)
        # sync (old behavior), cluster (only returns and publishes)
        self.syndic_mode = self.opts.get("syndic_mode", "sync")
        self.syndic_failover = self.opts.get("syndic_failover", "random")

        self.auth_wait = self.opts["acceptance_wait_time"]
        self.max_auth_wait = self.opts["acceptance_wait_time_max"]

        self._has_master = threading.Event()
        self.jid_forward_cache = set()

        if io_loop is None:
            self.io_loop = salt.ext.tornado.ioloop.IOLoop.current()
        else:
            self.io_loop = io_loop

        # List of events
        self.raw_events = []
        # Dict of rets: {master_id: {event_tag: job_ret, ...}, ...}
        self.job_rets = {}
        # List of delayed job_rets which was unable to send for some reason and will be resend to
        # any available master
        self.delayed = []
        # Keep track of retries for Syndics between multiple Master of Masters
        self.tries = collections.defaultdict(int)
        # Active pub futures: {master_id: (future, [job_ret, ...]), ...}
        self.pub_futures = {}

    def _spawn_syndics(self):
        """
        Spawn all the coroutines which will sign in the syndics
        """
        self._syndics = OrderedDict()  # mapping of opts['master'] -> syndic
        masters = self.opts["master"]
        if not isinstance(masters, list):
            masters = [masters]
        for master in masters:
            s_opts = copy.copy(self.opts)
            s_opts["master"] = master
            self._syndics[master] = self._connect_syndic(s_opts)

    @salt.ext.tornado.gen.coroutine
    def _connect_syndic(self, opts):
        """
        Create a syndic, and asynchronously connect it to a master
        """
        last = 0  # never have we signed in
        auth_wait = opts["acceptance_wait_time"]
        failed = False
        while True:
            log.debug("Syndic attempting to connect to %s", opts["master"])
            try:
                syndic = Syndic(
                    opts,
                    timeout=self.SYNDIC_CONNECT_TIMEOUT,
                    safe=False,
                    io_loop=self.io_loop,
                )
                yield syndic.connect_master(failed=failed)
                # set up the syndic to handle publishes (specifically not event forwarding)
                syndic.tune_in_no_block()

                # Send an event to the master that the minion is live
                syndic.fire_master_syndic_start()

                log.info("Syndic successfully connected to %s", opts["master"])
                break
            except SaltClientError as exc:
                failed = True
                log.error(
                    "Error while bringing up syndic for multi-syndic. Is the "
                    "master at %s responding?",
                    opts["master"],
                )
                if auth_wait < self.max_auth_wait:
                    auth_wait += self.auth_wait
                yield salt.ext.tornado.gen.sleep(auth_wait)  # TODO: log?
            except (KeyboardInterrupt, SystemExit):  # pylint: disable=try-except-raise
                raise
            except Exception:  # pylint: disable=broad-except
                failed = True
                log.critical(
                    "Unexpected error while connecting to %s",
                    opts["master"],
                    exc_info=True,
                )

        raise salt.ext.tornado.gen.Return(syndic)

    def _mark_master_dead(self, master):
        """
        Mark a master as dead. This will start the sign-in routine
        """
        # if its connected, mark it dead
        if self._syndics[master].done():
            syndic = self._syndics[master].result()  # pylint: disable=no-member
            self._syndics[master] = syndic.reconnect()
        else:
            # TODO: debug?
            log.info(
                "Attempting to mark %s as dead, although it is already marked dead",
                master,
            )

    def _call_syndic(self, func, args=(), kwargs=None, master_id=None):
        """
        Wrapper to call a given func on a syndic, best effort to get the one you asked for
        """
        if kwargs is None:
            kwargs = {}
        successful = False
        # Call for each master
        for master, syndic_future in self.iter_master_options(master_id):
            if not syndic_future.done() or syndic_future.exception():
                log.error(
                    "Unable to call %s on %s, that syndic is not connected",
                    func,
                    master,
                )
                continue

            try:
                getattr(syndic_future.result(), func)(*args, **kwargs)
                successful = True
            except SaltClientError:
                log.error("Unable to call %s on %s, trying another...", func, master)
                self._mark_master_dead(master)
        if not successful:
            log.critical("Unable to call %s on any masters!", func)

    def _return_pub_syndic(self, values, master_id=None):
        """
        Wrapper to call the '_return_pub_multi' a syndic, best effort to get the one you asked for
        """
        func = "_return_pub_multi"
        for master, syndic_future in self.iter_master_options(master_id):
            if not syndic_future.done() or syndic_future.exception():
                log.error(
                    "Unable to call %s on %s, that syndic is not connected",
                    func,
                    master,
                )
                continue

            future, data = self.pub_futures.get(master, (None, None))
            if future is not None:
                if not future.done():
                    if master == master_id:
                        # Targeted master previous send not done yet, call again later
                        return False
                    else:
                        # Fallback master is busy, try the next one
                        continue
                elif future.exception():
                    # Previous execution on this master returned an error
                    log.error(
                        "Unable to call %s on %s, trying another...", func, master
                    )
                    self._mark_master_dead(master)
                    del self.pub_futures[master]
                    self.tries[master] += 1
                    if self.tries[master] < self.opts.get("syndic_retries", 3):
                        # Add not sent data to the delayed list and try the next master
                        self.delayed.extend(data)
                    else:
                        self.tries = collections.defaultdict(int)
                        return True
                    continue
                else:
                    self.tries = collections.defaultdict(int)

            future = getattr(syndic_future.result(), func)(
                values, "_syndic_return", timeout=self._return_retry_timer(), sync=False
            )
            self.pub_futures[master] = (future, values)
            return True
        # Loop done and didn't exit: wasn't sent, try again later
        return False

    def iter_master_options(self, master_id=None):
        """
        Iterate (in order) over your options for master
        """
        masters = list(self._syndics.keys())
        if self.opts["syndic_failover"] == "random":
            random.shuffle(masters)
        if master_id not in self._syndics:
            master_id = masters.pop(0)
        else:
            masters.remove(master_id)

        while True:
            yield master_id, self._syndics[master_id]
            if not masters:
                break
            master_id = masters.pop(0)

    def _reset_event_aggregation(self):
        self.job_rets = {}
        self.raw_events = []

    def reconnect_event_bus(self, something):
        future = self.local.event.set_event_handler(self._process_event)
        self.io_loop.add_future(future, self.reconnect_event_bus)

    # Syndic Tune In
    def tune_in(self):
        """
        Lock onto the publisher. This is the main event loop for the syndic
        """
        self._spawn_syndics()
        # Instantiate the local client
        self.local = salt.client.get_local_client(
            self.opts["_minion_conf_file"], io_loop=self.io_loop
        )
        self.local.event.subscribe("")

        log.debug("SyndicManager '%s' trying to tune in", self.opts["id"])

        # register the event sub to the poller
        self.job_rets = {}
        self.raw_events = []
        self._reset_event_aggregation()
        future = self.local.event.set_event_handler(self._process_event)
        self.io_loop.add_future(future, self.reconnect_event_bus)

        # forward events every syndic_event_forward_timeout
        self.forward_events = salt.ext.tornado.ioloop.PeriodicCallback(
            self._forward_events,
            self.opts["syndic_event_forward_timeout"] * 1000,
        )
        self.forward_events.start()

        # Make sure to gracefully handle SIGUSR1
        enable_sigusr1_handler()

        self.io_loop.start()

    def _process_event(self, raw):
        # TODO: cleanup: Move down into event class
        mtag, data = self.local.event.unpack(raw)
        log.trace("Got event %s", mtag)  # pylint: disable=no-member
        job_event = False
        return_event = True

        tag_parts = mtag.split("/")
        if (
            len(tag_parts) >= 4
            and tag_parts[1] == "job"
            and salt.utils.jid.is_jid(tag_parts[2])
        ):
            job_event = True

        if self.syndic_mode == "cluster" and data.get("master_id", 0) == self.opts.get(
            "master_id", 1
        ):
            return_event = False

        if job_event and tag_parts[3] == "ret" and "return" in data:
            if "jid" not in data:
                # Not a job return
                return
            if not return_event:
                log.debug("Return received with matching master_id, not forwarding")
                return

            master = data.get("master_id")
            jdict = self.job_rets.setdefault(master, {}).setdefault(mtag, {})
            if not jdict:
                jdict["__fun__"] = data.get("fun")
                jdict["__jid__"] = data["jid"]
                jdict["__load__"] = {}
                fstr = "{}.get_load".format(self.opts["master_job_cache"])
                # Only need to forward each load once. Don't hit the disk
                # for every minion return!
                if data["jid"] not in self.jid_forward_cache:
                    jdict["__load__"].update(self.mminion.returners[fstr](data["jid"]))
                    self.jid_forward_cache.add(data["jid"])
                    if (
                        len(self.jid_forward_cache)
                        > self.opts["syndic_jid_forward_cache_hwm"]
                    ):
                        # Pop the oldest jid from the cache
                        tmp = sorted(list(self.jid_forward_cache))
                        tmp.pop(0)
                        self.jid_forward_cache = set(tmp)
            if master is not None:
                # __'s to make sure it doesn't print out on the master cli
                jdict["__master_id__"] = master
            ret = {}
            for key in "return", "retcode", "success", "fun_args":
                if key in data:
                    ret[key] = data[key]
            jdict[data["id"]] = ret
        else:
            # TODO: config to forward these? If so we'll have to keep track of who
            # has seen them
            # if we are the top level masters-- don't forward all the minion events

            if (
                self.syndic_mode == "sync"
                # Even in cluster mode we need to forward the raw event with the minions
                # list to determine which minions we expect to return on the master of masters.
                or (
                    return_event and (salt.utils.jid.is_jid(mtag) and "minions" in data)
                )
            ):
                # Add generic event aggregation here
                if "retcode" not in data:
                    self.raw_events.append({"data": data, "tag": mtag})

    def _forward_events(self):
        log.trace("Forwarding events")  # pylint: disable=no-member
        if self.raw_events:
            events = self.raw_events
            self.raw_events = []
            self._call_syndic(
                "_fire_master",
                kwargs={
                    "events": events,
                    "pretag": tagify(self.opts["id"], base="syndic"),
                    "timeout": self._return_retry_timer(),
                },
            )
        if self.delayed:
            res = self._return_pub_syndic(self.delayed)
            if res:
                self.delayed = []
        for master in list(self.job_rets.keys()):
            values = list(self.job_rets[master].values())
            res = self._return_pub_syndic(values, master_id=master)
            if res:
                del self.job_rets[master]

    def destroy(self):
        if self._closing is True:
            return
        self._closing = True
        if self.local is not None:
            self.local.destroy()
            self.local = None
        if hasattr(self, "mminion") and self.mminion is not None:
            self.mminion.destroy()
            self.mminion = None


class ProxyMinionManager(MinionManager):
    """
    Create the multi-minion interface but for proxy minions
    """

    def _create_minion_object(
        self,
        opts,
        timeout,
        safe,
        io_loop=None,
        loaded_base_name=None,
        jid_queue=None,
        load_grains=True,
    ):
        """
        Helper function to return the correct type of object
        """
        return ProxyMinion(
            opts,
            timeout,
            safe,
            io_loop=io_loop,
            loaded_base_name=loaded_base_name,
            jid_queue=jid_queue,
            load_grains=True,
        )


def proxy_load_failure_message(proxy_loader, fq_proxyname):
    """
    Build the error message a proxy minion should abort with when its
    proxymodule's ``init`` and/or ``shutdown`` are unavailable.

    Historically all three call sites (``salt.metaproxy.proxy``,
    ``salt.metaproxy.deltaproxy`` and ``salt.minion.ProxyMinion``) emitted
    a single hard-coded sentence — "Proxymodule X is missing an init() or
    a shutdown() or both" — regardless of *why* those functions weren't
    in the loader. In practice that wording is wrong far more often than
    it is right: a missing dependency, an ``ImportError`` while loading
    the proxymodule, or any ``__virtual__()`` returning ``False`` all
    surface the same misleading message even though the module itself
    defines both functions.

    This helper inspects the proxy ``LazyLoader`` and distinguishes the
    two situations:

    * If the proxymodule itself never loaded (it is in the loader's
      ``missing_modules``), surface the underlying reason via
      :meth:`LazyLoader.missing_fun_string` so the operator can see the
      real cause (e.g. a failed ``__virtual__`` or import error).
    * Otherwise keep the historical "missing an init() or a shutdown()"
      wording — that case really does indicate a malformed proxymodule.

    Both branches end with the same "Salt-proxy aborted." suffix that
    callers and external log scrapers may rely on.
    """
    proxy_init_func_name = f"{fq_proxyname}.init"
    if fq_proxyname not in proxy_loader.loaded_modules:
        reason = proxy_loader.missing_fun_string(proxy_init_func_name)
        return (
            f"Proxymodule {fq_proxyname} could not be loaded: {reason}. "
            "Salt-proxy aborted."
        )
    return (
        f"Proxymodule {fq_proxyname} is missing an init() or a shutdown() "
        "or both. Check your proxymodule.  Salt-proxy aborted."
    )


def _metaproxy_call(opts, fn_name):
    loaded_base_name = "{}.{}".format(opts["id"], salt.loader.lazy.LOADED_BASE_NAME)
    metaproxy = salt.loader.metaproxy(opts, loaded_base_name=loaded_base_name)
    try:
        metaproxy_name = opts["metaproxy"]
    except KeyError:
        metaproxy_name = "proxy"
        log.debug(
            "No metaproxy key found in opts for id %s. Defaulting to standard proxy"
            " minion",
            opts["id"],
        )

    metaproxy_fn = metaproxy_name + "." + fn_name
    return metaproxy[metaproxy_fn]


class ProxyMinion(Minion):
    """
    This class instantiates a 'proxy' minion--a minion that does not manipulate
    the host it runs on, but instead manipulates a device that cannot run a minion.
    """

    # TODO: better name...
    @salt.ext.tornado.gen.coroutine
    def _post_master_init(self, master):
        """
        Function to finish init after connecting to a master

        This is primarily loading modules, pillars, etc. (since they need
        to know which master they connected to)

        If this function is changed, please check Minion._post_master_init
        to see if those changes need to be propagated.

        ProxyMinions need a significantly different post master setup,
        which is why the differences are not factored out into separate helper
        functions.
        """
        mp_call = _metaproxy_call(self.opts, "post_master_init")
        return mp_call(self, master)

    @salt.ext.tornado.gen.coroutine
    def subproxy_post_master_init(self, minion_id, uid):
        """
        Function to finish init for the sub proxies

        :rtype : None
        """
        mp_call = _metaproxy_call(self.opts, "subproxy_post_master_init")
        return mp_call(self, minion_id, uid)

    def tune_in(self, start=True):
        """
        Lock onto the publisher. This is the main event loop for the minion
        :rtype : None
        """
        mp_call = _metaproxy_call(self.opts, "tune_in")
        return mp_call(self, start)

    def _target_load(self, load):
        """
        Verify that the publication is valid and applies to this minion
        """
        mp_call = _metaproxy_call(self.opts, "target_load")
        return mp_call(self, load)

    def _handle_payload(self, payload):
        mp_call = _metaproxy_call(self.opts, "handle_payload")
        return mp_call(self, payload)

    @salt.ext.tornado.gen.coroutine
    def _handle_decoded_payload(self, data):
        mp_call = _metaproxy_call(self.opts, "handle_decoded_payload")
        return mp_call(self, data)

    @classmethod
    def _target(cls, minion_instance, opts, data, connected, creds_map):

        mp_call = _metaproxy_call(opts, "target")
        return mp_call(cls, minion_instance, opts, data, connected, creds_map)

    @classmethod
    def _thread_return(cls, minion_instance, opts, data):
        mp_call = _metaproxy_call(opts, "thread_return")
        return mp_call(cls, minion_instance, opts, data)

    @classmethod
    def _thread_multi_return(cls, minion_instance, opts, data):
        mp_call = _metaproxy_call(opts, "thread_multi_return")
        return mp_call(cls, minion_instance, opts, data)


class SProxyMinion(SMinion):
    """
    Create an object that has loaded all of the minion module functions,
    grains, modules, returners etc.  The SProxyMinion allows developers to
    generate all of the salt minion functions and present them with these
    functions for general use.
    """

    def gen_modules(self, initial_load=False, context=None):
        """
        Tell the minion to reload the execution modules

        CLI Example:

        .. code-block:: bash

            salt '*' sys.reload_modules
        """
        # need sync of custom grains as may be used in pillar compilation
        salt.utils.extmods.sync(self.opts, "grains")
        self.opts["grains"] = salt.loader.grains(self.opts)
        self.opts["pillar"] = salt.pillar.get_pillar(
            self.opts,
            self.opts["grains"],
            self.opts["id"],
            saltenv=self.opts["saltenv"],
            pillarenv=self.opts.get("pillarenv"),
        ).compile_pillar()

        if "proxy" not in self.opts["pillar"] and "proxy" not in self.opts:
            errmsg = (
                'No "proxy" configuration key found in pillar or opts '
                "dictionaries for id {id}. Check your pillar/options "
                "configuration and contents. Salt-proxy aborted.".format(
                    id=self.opts["id"]
                )
            )
            log.error(errmsg)
            self._running = False
            raise SaltSystemExit(code=salt.defaults.exitcodes.EX_GENERIC, msg=errmsg)

        if "proxy" not in self.opts:
            self.opts["proxy"] = self.opts["pillar"]["proxy"]

        # Then load the proxy module
        self.proxy = salt.loader.proxy(self.opts)

        self.utils = salt.loader.utils(self.opts, proxy=self.proxy, context=context)

        self.functions = salt.loader.minion_mods(
            self.opts, utils=self.utils, notify=False, proxy=self.proxy, context=context
        )
        self.returners = salt.loader.returners(
            self.opts, functions=self.functions, proxy=self.proxy, context=context
        )
        self.matchers = salt.loader.matchers(self.opts)
        self.functions["sys.reload_modules"] = self.gen_modules
        self.executors = salt.loader.executors(
            self.opts,
            functions=self.functions,
            proxy=self.proxy,
            context=context,
        )

        fq_proxyname = self.opts["proxy"]["proxytype"]

        # we can then sync any proxymodules down from the master
        # we do a sync_all here in case proxy code was installed by
        # SPM or was manually placed in /srv/salt/_modules etc.
        self.functions["saltutil.sync_all"](saltenv=self.opts["saltenv"])

        self.functions.pack["__proxy__"] = self.proxy
        self.proxy.pack["__salt__"] = self.functions
        self.proxy.pack["__ret__"] = self.returners
        self.proxy.pack["__pillar__"] = self.opts["pillar"]

        # Reload utils as well (chicken and egg, __utils__ needs __proxy__ and __proxy__ needs __utils__
        self.utils = salt.loader.utils(self.opts, proxy=self.proxy, context=context)
        self.proxy.pack["__utils__"] = self.utils

        # Reload all modules so all dunder variables are injected
        self.proxy.reload_modules()

        if (
            f"{fq_proxyname}.init" not in self.proxy
            or f"{fq_proxyname}.shutdown" not in self.proxy
        ):
            errmsg = proxy_load_failure_message(self.proxy, fq_proxyname)
            log.error(errmsg)
            self._running = False
            raise SaltSystemExit(code=salt.defaults.exitcodes.EX_GENERIC, msg=errmsg)

        self.module_executors = self.proxy.get(
            f"{fq_proxyname}.module_executors", lambda: []
        )()
        proxy_init_fn = self.proxy[fq_proxyname + ".init"]
        proxy_init_fn(self.opts)

        self.opts["grains"] = salt.loader.grains(self.opts, proxy=self.proxy)

        #  Sync the grains here so the proxy can communicate them to the master
        self.functions["saltutil.sync_grains"](saltenv="base")
        self.grains_cache = self.opts["grains"]
        self.ready = True