1//===---------- Linux implementation of the POSIX munmap function ---------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "src/sys/mman/munmap.h"
10
11#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
12#include "src/__support/common.h"
13
14#include "src/errno/libc_errno.h"
15#include <sys/syscall.h> // For syscall numbers.
16
17namespace LIBC_NAMESPACE {
18
19// This function is currently linux only. It has to be refactored suitably if
20// mmap is to be supported on non-linux operating systems also.
21LLVM_LIBC_FUNCTION(int, munmap, (void *addr, size_t size)) {
22 int ret = LIBC_NAMESPACE::syscall_impl<int>(
23 SYS_munmap, ts: reinterpret_cast<long>(addr), ts: size);
24
25 // A negative return value indicates an error with the magnitude of the
26 // value being the error code.
27 if (ret < 0) {
28 libc_errno = -ret;
29 return -1;
30 }
31
32 return 0;
33}
34
35} // namespace LIBC_NAMESPACE
36

source code of libc/src/sys/mman/linux/munmap.cpp