nsz Git - musl/blob - src/thread/pthread_self.c

   1 #include "pthread_impl.h"
   2
   3 static struct pthread main_thread;
   4
   5 #undef errno
   6 static int *errno_location()
   7 {
   8         return pthread_self()->errno_ptr;
   9 }
  10
  11 static int init_main_thread()
  12 {
  13         main_thread.tlsdesc[0] = -1;
  14         main_thread.tlsdesc[1] = (long)&main_thread;
  15         main_thread.tlsdesc[2] = SIZE_MAX/PAGE_SIZE;
  16         main_thread.tlsdesc[3] = 0x51;
  17         main_thread.self = &main_thread;
  18         main_thread.errno_ptr = __errno_location();
  19         if (__set_thread_area(main_thread.tlsdesc) < 0)
  20                 return -1;
  21         syscall1(__NR_set_tid_address, (long)&main_thread.tid);
  22         libc.errno_location = errno_location;
  23         main_thread.tid = main_thread.pid = getpid();
  24         return 0;
  25 }
  26
  27 #undef pthread_self
  28
  29 pthread_t pthread_self()
  30 {
  31         static int init, failed;
  32         if (!init) {
  33                 if (failed) return 0;
  34                 if (init_main_thread() < 0) failed = 1;
  35                 if (failed) return 0;
  36                 init = 1;
  37         }
  38         return __pthread_self();
  39 }