musl/src/thread/pthread_atfork.c

49 lines
911 B
C

#include <pthread.h>
#include "libc.h"
static struct atfork_funcs {
void (*prepare)(void);
void (*parent)(void);
void (*child)(void);
struct atfork_funcs *prev, *next;
} *funcs;
static int lock[2];
void __fork_handler(int who)
{
struct atfork_funcs *p;
if (!funcs) return;
if (who < 0) {
LOCK(lock);
for (p=funcs; p; p = p->next) {
if (p->prepare) p->prepare();
funcs = p;
}
} else {
for (p=funcs; p; p = p->prev) {
if (!who && p->parent) p->parent();
else if (who && p->child) p->child();
funcs = p;
}
UNLOCK(lock);
}
}
int pthread_atfork(void (*prepare)(void), void (*parent)(void), void (*child)(void))
{
struct atfork_funcs *new = malloc(sizeof *new);
if (!new) return -1;
LOCK(lock);
new->next = funcs;
new->prev = 0;
new->prepare = prepare;
new->parent = parent;
new->child = child;
if (funcs) funcs->prev = new;
funcs = new;
UNLOCK(lock);
return 0;
}