/usr/lib/python2.7/distutils/spawn.py is in libpython2.7-stdlib 2.7.6-8ubuntu0.5.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 | """distutils.spawn
Provides the 'spawn()' function, a front-end to various platform-
specific functions for launching another program in a sub-process.
Also provides the 'find_executable()' to search the path for a given
executable name.
"""
__revision__ = "$Id$"
import sys
import os
from distutils.errors import DistutilsPlatformError, DistutilsExecError
from distutils.debug import DEBUG
from distutils import log
def spawn(cmd, search_path=1, verbose=0, dry_run=0):
"""Run another program, specified as a command list 'cmd', in a new process.
'cmd' is just the argument list for the new process, ie.
cmd[0] is the program to run and cmd[1:] are the rest of its arguments.
There is no way to run a program with a name different from that of its
executable.
If 'search_path' is true (the default), the system's executable
search path will be used to find the program; otherwise, cmd[0]
must be the exact path to the executable. If 'dry_run' is true,
the command will not actually be run.
Raise DistutilsExecError if running the program fails in any way; just
return on success.
"""
# cmd is documented as a list, but just in case some code passes a tuple
# in, protect our %-formatting code against horrible death
cmd = list(cmd)
if os.name == 'posix':
_spawn_posix(cmd, search_path, dry_run=dry_run)
elif os.name == 'nt':
_spawn_nt(cmd, search_path, dry_run=dry_run)
elif os.name == 'os2':
_spawn_os2(cmd, search_path, dry_run=dry_run)
else:
raise DistutilsPlatformError, \
"don't know how to spawn programs on platform '%s'" % os.name
def _nt_quote_args(args):
"""Quote command-line arguments for DOS/Windows conventions.
Just wraps every argument which contains blanks in double quotes, and
returns a new argument list.
"""
# XXX this doesn't seem very robust to me -- but if the Windows guys
# say it'll work, I guess I'll have to accept it. (What if an arg
# contains quotes? What other magic characters, other than spaces,
# have to be escaped? Is there an escaping mechanism other than
# quoting?)
for i, arg in enumerate(args):
if ' ' in arg:
args[i] = '"%s"' % arg
return args
def _spawn_nt(cmd, search_path=1, verbose=0, dry_run=0):
executable = cmd[0]
cmd = _nt_quote_args(cmd)
if search_path:
# either we find one or it stays the same
executable = find_executable(executable) or executable
log.info(' '.join([executable] + cmd[1:]))
if not dry_run:
# spawn for NT requires a full path to the .exe
try:
rc = os.spawnv(os.P_WAIT, executable, cmd)
except OSError, exc:
# this seems to happen when the command isn't found
if not DEBUG:
cmd = executable
raise DistutilsExecError, \
"command %r failed: %s" % (cmd, exc[-1])
if rc != 0:
# and this reflects the command running but failing
if not DEBUG:
cmd = executable
raise DistutilsExecError, \
"command %r failed with exit status %d" % (cmd, rc)
def _spawn_os2(cmd, search_path=1, verbose=0, dry_run=0):
executable = cmd[0]
if search_path:
# either we find one or it stays the same
executable = find_executable(executable) or executable
log.info(' '.join([executable] + cmd[1:]))
if not dry_run:
# spawnv for OS/2 EMX requires a full path to the .exe
try:
rc = os.spawnv(os.P_WAIT, executable, cmd)
except OSError, exc:
# this seems to happen when the command isn't found
if not DEBUG:
cmd = executable
raise DistutilsExecError, \
"command %r failed: %s" % (cmd, exc[-1])
if rc != 0:
# and this reflects the command running but failing
if not DEBUG:
cmd = executable
log.debug("command %r failed with exit status %d" % (cmd, rc))
raise DistutilsExecError, \
"command %r failed with exit status %d" % (cmd, rc)
if sys.platform == 'darwin':
from distutils import sysconfig
_cfg_target = None
_cfg_target_split = None
def _spawn_posix(cmd, search_path=1, verbose=0, dry_run=0):
log.info(' '.join(cmd))
if dry_run:
return
executable = cmd[0]
exec_fn = search_path and os.execvp or os.execv
env = None
if sys.platform == 'darwin':
global _cfg_target, _cfg_target_split
if _cfg_target is None:
_cfg_target = sysconfig.get_config_var(
'MACOSX_DEPLOYMENT_TARGET') or ''
if _cfg_target:
_cfg_target_split = [int(x) for x in _cfg_target.split('.')]
if _cfg_target:
# ensure that the deployment target of build process is not less
# than that used when the interpreter was built. This ensures
# extension modules are built with correct compatibility values
cur_target = os.environ.get('MACOSX_DEPLOYMENT_TARGET', _cfg_target)
if _cfg_target_split > [int(x) for x in cur_target.split('.')]:
my_msg = ('$MACOSX_DEPLOYMENT_TARGET mismatch: '
'now "%s" but "%s" during configure'
% (cur_target, _cfg_target))
raise DistutilsPlatformError(my_msg)
env = dict(os.environ,
MACOSX_DEPLOYMENT_TARGET=cur_target)
exec_fn = search_path and os.execvpe or os.execve
pid = os.fork()
if pid == 0: # in the child
try:
if env is None:
exec_fn(executable, cmd)
else:
exec_fn(executable, cmd, env)
except OSError, e:
if not DEBUG:
cmd = executable
sys.stderr.write("unable to execute %r: %s\n" %
(cmd, e.strerror))
os._exit(1)
if not DEBUG:
cmd = executable
sys.stderr.write("unable to execute %r for unknown reasons" % cmd)
os._exit(1)
else: # in the parent
# Loop until the child either exits or is terminated by a signal
# (ie. keep waiting if it's merely stopped)
while 1:
try:
pid, status = os.waitpid(pid, 0)
except OSError, exc:
import errno
if exc.errno == errno.EINTR:
continue
if not DEBUG:
cmd = executable
raise DistutilsExecError, \
"command %r failed: %s" % (cmd, exc[-1])
if os.WIFSIGNALED(status):
if not DEBUG:
cmd = executable
raise DistutilsExecError, \
"command %r terminated by signal %d" % \
(cmd, os.WTERMSIG(status))
elif os.WIFEXITED(status):
exit_status = os.WEXITSTATUS(status)
if exit_status == 0:
return # hey, it succeeded!
else:
if not DEBUG:
cmd = executable
raise DistutilsExecError, \
"command %r failed with exit status %d" % \
(cmd, exit_status)
elif os.WIFSTOPPED(status):
continue
else:
if not DEBUG:
cmd = executable
raise DistutilsExecError, \
"unknown error executing %r: termination status %d" % \
(cmd, status)
def find_executable(executable, path=None):
"""Tries to find 'executable' in the directories listed in 'path'.
A string listing directories separated by 'os.pathsep'; defaults to
os.environ['PATH']. Returns the complete filename or None if not found.
"""
if path is None:
path = os.environ['PATH']
paths = path.split(os.pathsep)
base, ext = os.path.splitext(executable)
if (sys.platform == 'win32' or os.name == 'os2') and (ext != '.exe'):
executable = executable + '.exe'
if not os.path.isfile(executable):
for p in paths:
f = os.path.join(p, executable)
if os.path.isfile(f):
# the file exists, we have a shot at spawn working
return f
return None
else:
return executable
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