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@vls
Created August 26, 2011 10:30
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Python 2.6.5 subprocess SIG_PIPE bug fix
from sub import *
import sys
import os
import types
import traceback
import gc
import signal
import errno
class Popen_new(Popen):
def _execute_child(self, args, executable, preexec_fn, close_fds,
cwd, env, universal_newlines,
startupinfo, creationflags, shell,
p2cread, p2cwrite,
c2pread, c2pwrite,
errread, errwrite):
"""Execute program (POSIX version)"""
if isinstance(args, types.StringTypes):
args = [args]
else:
args = list(args)
if shell:
args = ["/bin/sh", "-c"] + args
if executable is None:
executable = args[0]
# For transferring possible exec failure from child to parent
# The first char specifies the exception type: 0 means
# OSError, 1 means some other error.
errpipe_read, errpipe_write = os.pipe()
try:
try:
self._set_cloexec_flag(errpipe_write)
gc_was_enabled = gc.isenabled()
# Disable gc to avoid bug where gc -> file_dealloc ->
# write to stderr -> hang. http://bugs.python.org/issue1336
gc.disable()
try:
self.pid = os.fork()
except:
if gc_was_enabled:
gc.enable()
raise
self._child_created = True
if self.pid == 0:
# Child
try:
# Close parent's pipe ends
if p2cwrite is not None:
os.close(p2cwrite)
if c2pread is not None:
os.close(c2pread)
if errread is not None:
os.close(errread)
os.close(errpipe_read)
# Dup fds for child
if p2cread is not None:
os.dup2(p2cread, 0)
if c2pwrite is not None:
os.dup2(c2pwrite, 1)
if errwrite is not None:
os.dup2(errwrite, 2)
# Close pipe fds. Make sure we don't close the same
# fd more than once, or standard fds.
if p2cread is not None and p2cread not in (0,):
os.close(p2cread)
if c2pwrite is not None and c2pwrite not in (p2cread, 1):
os.close(c2pwrite)
if errwrite is not None and errwrite not in (p2cread, c2pwrite, 2):
os.close(errwrite)
# Close all other fds, if asked for
if close_fds:
self._close_fds(but=errpipe_write)
if cwd is not None:
os.chdir(cwd)
import signal
signals = ('SIGPIPE', 'SIGXFZ', 'SIGXFSZ')
for sig in signals:
if hasattr(signal, sig):
signal.signal(getattr(signal, sig), signal.SIG_DFL)
if preexec_fn:
preexec_fn()
if env is None:
os.execvp(executable, args)
else:
os.execvpe(executable, args, env)
except:
exc_type, exc_value, tb = sys.exc_info()
# Save the traceback and attach it to the exception object
exc_lines = traceback.format_exception(exc_type,
exc_value,
tb)
exc_value.child_traceback = ''.join(exc_lines)
os.write(errpipe_write, pickle.dumps(exc_value))
# This exitcode won't be reported to applications, so it
# really doesn't matter what we return.
os._exit(255)
# Parent
if gc_was_enabled:
gc.enable()
finally:
# be sure the FD is closed no matter what
os.close(errpipe_write)
if p2cread is not None and p2cwrite is not None:
os.close(p2cread)
if c2pwrite is not None and c2pread is not None:
os.close(c2pwrite)
if errwrite is not None and errread is not None:
os.close(errwrite)
# Wait for exec to fail or succeed; possibly raising exception
# Exception limited to 1M
data = _eintr_retry_call(os.read, errpipe_read, 1048576)
finally:
# be sure the FD is closed no matter what
os.close(errpipe_read)
if data != "":
_eintr_retry_call(os.waitpid, self.pid, 0)
child_exception = pickle.loads(data)
for fd in (p2cwrite, c2pread, errread):
if fd is not None:
os.close(fd)
raise child_exception
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