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

   1 #include <unistd.h>
   2 #include <string.h>
   3 #include <signal.h>
   4 #include "syscall.h"
   5 #include "libc.h"
   6 #include "pthread_impl.h"
   7
   8 static void dummy(int x)
   9 {
  10 }
  11
  12 weak_alias(dummy, __fork_handler);
  13
  14 pid_t fork(void)
  15 {
  16         pid_t ret;
  17         sigset_t set;
  18         __fork_handler(-1);
  19         __block_all_sigs(&set);
  20 #ifdef SYS_fork
  21         ret = __syscall(SYS_fork);
  22 #else
  23         ret = __syscall(SYS_clone, SIGCHLD, 0);
  24 #endif
  25         if (!ret) {
  26                 pthread_t self = __pthread_self();
  27                 self->tid = __syscall(SYS_gettid);
  28                 self->robust_list.off = 0;
  29                 self->robust_list.pending = 0;
  30                 self->next = self->prev = self;
  31                 libc.threads_minus_1 = 0;
  32         }
  33         __restore_sigs(&set);
  34         __fork_handler(!ret);
  35         return __syscall_ret(ret);
  36 }