mremap.c raw

   1  #define _GNU_SOURCE
   2  #include <unistd.h>
   3  #include <sys/mman.h>
   4  #include <errno.h>
   5  #include <stdint.h>
   6  #include <stdarg.h>
   7  #include "syscall.h"
   8  
   9  static void dummy(void) { }
  10  weak_alias(dummy, __vm_wait);
  11  
  12  void *__mremap(void *old_addr, size_t old_len, size_t new_len, int flags, ...)
  13  {
  14  	va_list ap;
  15  	void *new_addr = 0;
  16  
  17  	if (new_len >= PTRDIFF_MAX) {
  18  		errno = ENOMEM;
  19  		return MAP_FAILED;
  20  	}
  21  
  22  	if (flags & MREMAP_FIXED) {
  23  		__vm_wait();
  24  		va_start(ap, flags);
  25  		new_addr = va_arg(ap, void *);
  26  		va_end(ap);
  27  	}
  28  
  29  	return (void *)syscall(SYS_mremap, old_addr, old_len, new_len, flags, new_addr);
  30  }
  31  
  32  weak_alias(__mremap, mremap);
  33