libc-top-half/musl/src/thread/__unmapself.c

   1 #include "pthread_impl.h"
   2 #include "atomic.h"
   3 #include "syscall.h"
   4 /* cheat and reuse CRTJMP macro from dynlink code */
   5 #include "dynlink.h"
   6
   7 static void *unmap_base;
   8 static size_t unmap_size;
   9 static char shared_stack[256];
  10
  11 static void do_unmap()
  12 {
  13         __syscall(SYS_munmap, unmap_base, unmap_size);
  14         __syscall(SYS_exit);
  15 }
  16
  17 void __unmapself(void *base, size_t size)
  18 {
  19         char *stack = shared_stack + sizeof shared_stack;
  20         stack -= (uintptr_t)stack % 16;
  21         unmap_base = base;
  22         unmap_size = size;
  23         CRTJMP(do_unmap, stack);
  24 }