github.com/afumu/libc@v0.0.6/musl/src/mman/mremap.c (about)

     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);