_Fork.c raw

   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  
   9  static void dummy(int x) { }
  10  weak_alias(dummy, __aio_atfork);
  11  
  12  pid_t _Fork(void)
  13  {
  14  	pid_t ret;
  15  	sigset_t set;
  16  	__block_all_sigs(&set);
  17  	__aio_atfork(-1);
  18  	LOCK(__abort_lock);
  19  #ifdef SYS_fork
  20  	ret = __syscall(SYS_fork);
  21  #else
  22  	ret = __syscall(SYS_clone, SIGCHLD, 0);
  23  #endif
  24  	if (!ret) {
  25  		pthread_t self = __pthread_self();
  26  		self->tid = __syscall(SYS_gettid);
  27  		self->robust_list.off = 0;
  28  		self->robust_list.pending = 0;
  29  		self->next = self->prev = self;
  30  		__thread_list_lock = 0;
  31  		libc.threads_minus_1 = 0;
  32  		if (libc.need_locks) libc.need_locks = -1;
  33  	}
  34  	UNLOCK(__abort_lock);
  35  	__aio_atfork(!ret);
  36  	__restore_sigs(&set);
  37  	return __syscall_ret(ret);
  38  }
  39