From 39fbf988a495e07335efc9f176ceced9b001e8c2 Mon Sep 17 00:00:00 2001
From: "Daniel P. Berrange" <berrange@redhat.com>
Date: Mon, 29 Jun 2015 17:13:39 +0100
Subject: [PATCH] processutils: allow process limits to be set

Add a 'limits' arg to execute() allowing a set of process
resource limits to be defined. This are set between the
fork and exec of the child process. The 'limits' arg is a
dict, whose keys are the resource.RLIMIT_* constants and
values are the desired limit as defined by resource.setrlimit()

eg

  execute(....
          limits={
		resource.RLIMIT_AS: 10 * units.Gi,
		resource.RLIMIT_NOFILE: 8 * units.Ki
	  })
---
 oslo_concurrency/processutils.py | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/oslo_concurrency/processutils.py b/oslo_concurrency/processutils.py
index 5958dbd..efc6186 100644
--- a/oslo_concurrency/processutils.py
+++ b/oslo_concurrency/processutils.py
@@ -21,6 +21,7 @@ import logging
 import multiprocessing
 import os
 import random
+import resource
 import shlex
 import signal
 import time
@@ -86,11 +87,21 @@ class NoRootWrapSpecified(Exception):
         super(NoRootWrapSpecified, self).__init__(message)
 
 
-def _subprocess_setup():
+def _subprocess_setup(limits):
     # Python installs a SIGPIPE handler by default. This is usually not what
     # non-Python subprocesses expect.
     signal.signal(signal.SIGPIPE, signal.SIG_DFL)
 
+    if limits is not None:
+        for resource in limits:
+            value = limits[resource]
+            # Allow plain 'int' for convenience when hard
+            # and soft limits are the same (which is the
+            # common case)
+            if type(value) == int:
+                value = (value, value)
+            resources.setrlimit(resource, value)
+
 
 LOG_ALL_ERRORS = 1
 LOG_FINAL_ERROR = 2
@@ -147,6 +158,8 @@ def execute(*cmd, **kwargs):
     :param binary:          On Python 3, return stdout and stderr as bytes if
                             binary is True, as Unicode otherwise.
     :type binary:           boolean
+    :param limits:          Update process resource limits
+    :type limits:           dict of resource.RLIMIT constants to values
     :returns:               (stdout, stderr) from process execution
     :raises:                :class:`UnknownArgumentError` on
                             receiving unknown arguments
@@ -167,6 +180,7 @@ def execute(*cmd, **kwargs):
     loglevel = kwargs.pop('loglevel', logging.DEBUG)
     log_errors = kwargs.pop('log_errors', None)
     binary = kwargs.pop('binary', False)
+    limits = kwargs.pop('limits', None)
 
     if isinstance(check_exit_code, bool):
         ignore_exit_code = not check_exit_code
@@ -204,6 +218,9 @@ def execute(*cmd, **kwargs):
             _PIPE = subprocess.PIPE  # pylint: disable=E1101
 
             if os.name == 'nt':
+                if limits is not None:
+                    raise InvalidArgumentError(
+                        _('Process limits not supported on this platform'))
                 preexec_fn = None
                 close_fds = False
             else:
@@ -215,7 +232,7 @@ def execute(*cmd, **kwargs):
                                    stdout=_PIPE,
                                    stderr=_PIPE,
                                    close_fds=close_fds,
-                                   preexec_fn=preexec_fn,
+                                   preexec_fn=lambda: preexec_fn(limits),
                                    shell=shell,
                                    cwd=cwd,
                                    env=env_variables)
-- 
2.4.3