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#include <unistd.h>
#include <errno.h>
#include "libc.h"
#include "lock.h"
#include "pthread_impl.h"
#include "fork_impl.h"
static volatile int *const dummy_lockptr = 0;
weak_alias(dummy_lockptr, __at_quick_exit_lockptr);
weak_alias(dummy_lockptr, __atexit_lockptr);
weak_alias(dummy_lockptr, __gettext_lockptr);
weak_alias(dummy_lockptr, __locale_lockptr);
weak_alias(dummy_lockptr, __random_lockptr);
weak_alias(dummy_lockptr, __sem_open_lockptr);
weak_alias(dummy_lockptr, __stdio_ofl_lockptr);
weak_alias(dummy_lockptr, __syslog_lockptr);
weak_alias(dummy_lockptr, __timezone_lockptr);
weak_alias(dummy_lockptr, __bump_lockptr);
weak_alias(dummy_lockptr, __vmlock_lockptr);
static volatile int *const *const atfork_locks[] = {
&__at_quick_exit_lockptr,
&__atexit_lockptr,
&__gettext_lockptr,
&__locale_lockptr,
&__random_lockptr,
&__sem_open_lockptr,
&__stdio_ofl_lockptr,
&__syslog_lockptr,
&__timezone_lockptr,
&__bump_lockptr,
};
static void dummy(int x) { }
weak_alias(dummy, __fork_handler);
weak_alias(dummy, __malloc_atfork);
weak_alias(dummy, __ldso_atfork);
static void dummy_0(void) { }
weak_alias(dummy_0, __tl_lock);
weak_alias(dummy_0, __tl_unlock);
pid_t fork(void)
{
sigset_t set;
__fork_handler(-1);
__block_app_sigs(&set);
int need_locks = libc.need_locks > 0;
if (need_locks) {
__ldso_atfork(-1);
__inhibit_ptc();
for (int i=0; i<sizeof atfork_locks/sizeof *atfork_locks; i++)
if (*atfork_locks[i]) LOCK(*atfork_locks[i]);
__malloc_atfork(-1);
__tl_lock();
}
pthread_t self=__pthread_self(), next=self->next;
pid_t ret = _Fork();
int errno_save = errno;
if (need_locks) {
if (!ret) {
for (pthread_t td=next; td!=self; td=td->next)
td->tid = -1;
if (__vmlock_lockptr) {
__vmlock_lockptr[0] = 0;
__vmlock_lockptr[1] = 0;
}
}
__tl_unlock();
__malloc_atfork(!ret);
for (int i=0; i<sizeof atfork_locks/sizeof *atfork_locks; i++)
if (*atfork_locks[i])
if (ret) UNLOCK(*atfork_locks[i]);
else **atfork_locks[i] = 0;
__release_ptc();
__ldso_atfork(!ret);
}
__restore_sigs(&set);
__fork_handler(!ret);
if (ret<0) errno = errno_save;
return ret;
}
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