mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-31 05:58:33 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 7

issue7213: Open the pipes used by subprocesses with the FD_CLOEXEC flag from

Browse source 
the C code, using pipe2() when available.  Adds unittests for close_fds and
cloexec behaviors.
This commit is contained in:
Gregory P. Smith 2010-12-13 07:59:39 +00:00
parent f560485388
commit 51ee270876
10 changed files with 195 additions and 17 deletions
Download patch file Download diff file Expand all files Collapse all files

44
Modules/_posixsubprocess.c
View file

@ -1,6 +1,10 @@
/* Authors: Gregory P. Smith & Jeffrey Yasskin */
#include "Python.h"
#ifdef HAVE_PIPE2
#define _GNU_SOURCE
#endif
#include <unistd.h>
#include <fcntl.h>
#define POSIX_CALL(call) if ((call) == -1) goto error
@ -398,6 +402,45 @@ Returns: the child process's PID.\n\
Raises: Only on an error in the parent process.\n\
");
PyDoc_STRVAR(subprocess_cloexec_pipe_doc,
"cloexec_pipe() -> (read_end, write_end)\n\n\
Create a pipe whose ends have the cloexec flag set.");
static PyObject *
subprocess_cloexec_pipe(PyObject *self, PyObject *noargs)
{
int fds[2];
int res;
#ifdef HAVE_PIPE2
Py_BEGIN_ALLOW_THREADS
res = pipe2(fds, O_CLOEXEC);
Py_END_ALLOW_THREADS
#else
/* We hold the GIL which offers some protection from other code calling
* fork() before the CLOEXEC flags have been set but we can't guarantee
* anything without pipe2(). */
long oldflags;
res = pipe(fds);
if (res == 0) {
oldflags = fcntl(fds[0], F_GETFD, 0);
if (oldflags < 0) res = oldflags;
}
if (res == 0)
res = fcntl(fds[0], F_SETFD, oldflags | FD_CLOEXEC);
if (res == 0) {
oldflags = fcntl(fds[1], F_GETFD, 0);
if (oldflags < 0) res = oldflags;
}
if (res == 0)
res = fcntl(fds[1], F_SETFD, oldflags | FD_CLOEXEC);
#endif
if (res != 0)
return PyErr_SetFromErrno(PyExc_OSError);
return Py_BuildValue("(ii)", fds[0], fds[1]);
}
/* module level code ********************************************************/
@ -407,6 +450,7 @@ PyDoc_STRVAR(module_doc,
static PyMethodDef module_methods[] = {
{"fork_exec", subprocess_fork_exec, METH_VARARGS, subprocess_fork_exec_doc},
{"cloexec_pipe", subprocess_cloexec_pipe, METH_NOARGS, subprocess_cloexec_pipe_doc},
{NULL, NULL} /* sentinel */
};