nsz Git - musl/blob - src/process/_Fork.c

   1 #include <unistd.h>
   2 #include <signal.h>
   3 #include "syscall.h"
   4 #include "libc.h"
   5 #include "lock.h"
   6 #include "pthread_impl.h"
   7 #include "aio_impl.h"
   8 #include "fork_impl.h"
   9
  10 static void dummy(int x) { }
  11 weak_alias(dummy, __aio_atfork);
  12
  13 void __post_Fork(int ret)
  14 {
  15         if (!ret) {
  16                 pthread_t self = __pthread_self();
  17                 self->tid = __syscall(SYS_set_tid_address, &__thread_list_lock);
  18                 self->robust_list.off = 0;
  19                 self->robust_list.pending = 0;
  20                 self->next = self->prev = self;
  21                 __thread_list_lock = 0;
  22                 libc.threads_minus_1 = 0;
  23                 if (libc.need_locks) libc.need_locks = -1;
  24         }
  25         UNLOCK(__abort_lock);
  26         if (!ret) __aio_atfork(1);
  27 }
  28
  29 pid_t _Fork(void)
  30 {
  31         pid_t ret;
  32         sigset_t set;
  33         __block_all_sigs(&set);
  34         LOCK(__abort_lock);
  35 #ifdef SYS_fork
  36         ret = __syscall(SYS_fork);
  37 #else
  38         ret = __syscall(SYS_clone, SIGCHLD, 0);
  39 #endif
  40         __post_Fork(ret);
  41         __restore_sigs(&set);
  42         return __syscall_ret(ret);
  43 }