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 17 namespace 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. 21 LLVM_LIBC_FUNCTION(int, munmap, (void *addr, size_t size)) { 22 int ret = LIBC_NAMESPACE::syscall_impl<int>( 23 SYS_munmap, reinterpret_cast<long>(addr), 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