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
   8 static void dummy(int x) { }
   9 weak_alias(dummy, __aio_atfork);
  10
  11 pid_t _Fork(void)
  12 {
  13         pid_t ret;
  14         sigset_t set;
  15         __block_all_sigs(&set);
  16         __aio_atfork(-1);
  17         LOCK(__abort_lock);
  18 #ifdef SYS_fork
  19         ret = __syscall(SYS_fork);
  20 #else
  21         ret = __syscall(SYS_clone, SIGCHLD, 0);
  22 #endif
  23         if (!ret) {
  24                 pthread_t self = __pthread_self();
  25                 self->tid = __syscall(SYS_gettid);
  26                 self->robust_list.off = 0;
  27                 self->robust_list.pending = 0;
  28                 self->next = self->prev = self;
  29                 __thread_list_lock = 0;
  30                 libc.threads_minus_1 = 0;
  31                 if (libc.need_locks) libc.need_locks = -1;
  32         }
  33         UNLOCK(__abort_lock);
  34         __aio_atfork(!ret);
  35         __restore_sigs(&set);
  36         return __syscall_ret(ret);
  37 }