mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-06-28 07:18:30 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

Work towards improving signals and processes

Browse source
This commit is contained in:
Justine Tunney 2021-01-27 19:34:02 -08:00
parent de703b182c
commit d7ac16a9ed
96 changed files with 1474 additions and 427 deletions
Download patch file Download diff file Expand all files Collapse all files

17
libc/calls/atfork.c
View file

@ -16,12 +16,13 @@
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/bits/bits.h"
#include "libc/macros.h"
#include "libc/runtime/runtime.h"
#include "libc/sysv/errfuns.h"
static struct AtFork {
size_t i;
volatile size_t i;
struct AtForkCallback {
void (*fn)(void *);
void *arg;
@ -33,17 +34,25 @@ static struct AtFork {
*
* @return 0 on success, or -1 w/ errno
* @note vfork() won't invoke callbacks
* @asyncsignalsafe
*/
int atfork(void *fn, void *arg) {
if (g_atfork.i == ARRAYLEN(g_atfork.p)) return enomem();
g_atfork.p[g_atfork.i++] = (struct AtForkCallback){.fn = fn, .arg = arg};
return 0;
size_t i;
for (;;) {
i = g_atfork.i;
if (i == ARRAYLEN(g_atfork.p)) return enomem();
if (cmpxchg(&g_atfork.i, i, i + 1)) {
g_atfork.p[i] = (struct AtForkCallback){.fn = fn, .arg = arg};
return 0;
}
}
}
/**
* Triggers callbacks registered by atfork().
*
* @note only fork() should call this
* @asyncsignalsafe
*/
void __onfork(void) {
size_t i;