mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-05-23 05:42:29 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

Overhaul process spawning

Browse source
This commit is contained in:
Justine Tunney 2023-09-10 08:12:43 -07:00
parent 99dc1281f5
commit 26e254fb4d
No known key found for this signature in database
GPG key ID: BE714B4575D6E328
96 changed files with 1848 additions and 1541 deletions
Download patch file Download diff file Expand all files Collapse all files

23
libc/stdio/popen.c
View file

@ -22,6 +22,7 @@
#include "libc/intrin/weaken.h"
#include "libc/paths.h"
#include "libc/runtime/runtime.h"
#include "libc/stdio/fflush.internal.h"
#include "libc/stdio/internal.h"
#include "libc/stdio/stdio.h"
#include "libc/sysv/consts/f.h"
@ -42,6 +43,7 @@
* @param mode can be:
* - `"r"` for reading from subprocess standard output
* - `"w"` for writing to subprocess standard input
* - `"e"` for `O_CLOEXEC` on returned file
* @raise EINVAL if `mode` is invalid or specifies read+write
* @raise EMFILE if process `RLIMIT_NOFILE` has been reached
* @raise ENFILE if system-wide file limit has been reached
@ -53,7 +55,7 @@
* @threadsafe
*/
FILE *popen(const char *cmdline, const char *mode) {
FILE *f;
FILE *f, *f2;
int e, rc, pid, dir, flags, pipefds[2];
flags = fopenflags(mode);
if ((flags & O_ACCMODE) == O_RDONLY) {
@ -77,6 +79,14 @@ FILE *popen(const char *cmdline, const char *mode) {
// we can't rely on cloexec because cocmd builtins don't execve
if (pipefds[0] != !dir) unassert(!close(pipefds[0]));
if (pipefds[1] != !dir) unassert(!close(pipefds[1]));
// "The popen() function shall ensure that any streams from
// previous popen() calls that remain open in the parent
// process are closed in the new child process." -POSIX
for (int i = 0; i < __fflush.handles.i; ++i) {
if ((f2 = __fflush.handles.p[i]) && f2->pid) {
close(f2->fd);
}
}
_Exit(_cocmd(3,
(char *[]){
"popen",
@ -88,18 +98,21 @@ FILE *popen(const char *cmdline, const char *mode) {
default:
f->pid = pid;
unassert(!close(pipefds[!dir]));
if (!(flags & O_CLOEXEC)) {
unassert(!fcntl(pipefds[dir], F_SETFD, 0));
}
return f;
case -1:
e = errno;
unassert(!fclose(f));
unassert(!close(pipefds[!dir]));
fclose(f);
close(pipefds[!dir]);
errno = e;
return NULL;
}
} else {
e = errno;
unassert(!close(pipefds[0]));
unassert(!close(pipefds[1]));
close(pipefds[0]);
close(pipefds[1]);
errno = e;
return NULL;
}