xref: /llvm-project/libc/src/__support/OSUtil/windows/io.cpp (revision ded080152acceca5d68014d63f5027a6d8266cbb)
1*ded08015SSirui Mu //===------------- Windows implementation of IO utils -----------*- C++ -*-===//
2*ded08015SSirui Mu //
3*ded08015SSirui Mu // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*ded08015SSirui Mu // See https://llvm.org/LICENSE.txt for license information.
5*ded08015SSirui Mu // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*ded08015SSirui Mu //
7*ded08015SSirui Mu //===----------------------------------------------------------------------===//
8*ded08015SSirui Mu 
9*ded08015SSirui Mu #include "io.h"
10*ded08015SSirui Mu #include "src/__support/macros/config.h"
11*ded08015SSirui Mu 
12*ded08015SSirui Mu // On Windows we cannot make direct syscalls since Microsoft changes system call
13*ded08015SSirui Mu // IDs periodically. We must rely on functions exported from ntdll.dll or
14*ded08015SSirui Mu // kernel32.dll to invoke system service procedures.
15*ded08015SSirui Mu #define WIN32_LEAN_AND_MEAN
16*ded08015SSirui Mu #include <Windows.h>
17*ded08015SSirui Mu 
18*ded08015SSirui Mu namespace LIBC_NAMESPACE_DECL {
19*ded08015SSirui Mu 
20*ded08015SSirui Mu void write_to_stderr(cpp::string_view msg) {
21*ded08015SSirui Mu   ::HANDLE stream = ::GetStdHandle(STD_ERROR_HANDLE);
22*ded08015SSirui Mu   ::WriteFile(stream, msg.data(), msg.size(), nullptr, nullptr);
23*ded08015SSirui Mu }
24*ded08015SSirui Mu 
25*ded08015SSirui Mu } // namespace LIBC_NAMESPACE_DECL
26