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

   1 #define _GNU_SOURCE
   2 #include "pthread_impl.h"
   3 #include "libc.h"
   4 #include <sys/mman.h>
   5
   6 int pthread_getattr_np(pthread_t t, pthread_attr_t *a)
   7 {
   8         *a = (pthread_attr_t){0};
   9         a->_a_detach = !!t->detached;
  10         if (t->stack) {
  11                 a->_a_stackaddr = (uintptr_t)t->stack;
  12                 a->_a_stacksize = t->stack_size;
  13         } else {
  14                 char *p = (void *)libc.auxv;
  15                 size_t l = PAGE_SIZE;
  16                 p += -(uintptr_t)p & PAGE_SIZE-1;
  17                 a->_a_stackaddr = (uintptr_t)p;
  18                 while (mremap(p-l-PAGE_SIZE, PAGE_SIZE, 2*PAGE_SIZE, 0)==MAP_FAILED && errno==ENOMEM)
  19                         l += PAGE_SIZE;
  20                 a->_a_stacksize = l;
  21         }
  22         return 0;
  23 }