1//===-- InitLLVM.cpp -----------------------------------------------------===//
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 "llvm/Support/InitLLVM.h"
10#include "llvm/ADT/StringRef.h"
11#include "llvm/Support/AutoConvert.h"
12#include "llvm/Support/Error.h"
13#include "llvm/Support/ErrorHandling.h"
14#include "llvm/Support/ManagedStatic.h"
15#include "llvm/Support/Signals.h"
16
17#ifdef _WIN32
18#include "llvm/Support/Windows/WindowsSupport.h"
19#endif
20
21#if defined(HAVE_UNISTD_H)
22#include <unistd.h>
23#else
24#ifndef STDIN_FILENO
25#define STDIN_FILENO 0
26#endif
27#ifndef STDOUT_FILENO
28#define STDOUT_FILENO 1
29#endif
30#ifndef STDERR_FILENO
31#define STDERR_FILENO 2
32#endif
33#endif
34
35void CleanupStdHandles(void *Cookie) {
36 llvm::raw_ostream *Outs = &llvm::outs(), *Errs = &llvm::errs();
37 Outs->flush();
38 Errs->flush();
39 llvm::restoreStdHandleAutoConversion(STDIN_FILENO);
40 llvm::restoreStdHandleAutoConversion(STDOUT_FILENO);
41 llvm::restoreStdHandleAutoConversion(STDERR_FILENO);
42}
43
44using namespace llvm;
45using namespace llvm::sys;
46
47InitLLVM::InitLLVM(int &Argc, const char **&Argv,
48 bool InstallPipeSignalExitHandler) {
49#ifndef NDEBUG
50 static std::atomic<bool> Initialized{false};
51 assert(!Initialized && "InitLLVM was already initialized!");
52 Initialized = true;
53#endif
54
55 // Bring stdin/stdout/stderr into a known state.
56 sys::AddSignalHandler(FnPtr: CleanupStdHandles, Cookie: nullptr);
57
58 if (InstallPipeSignalExitHandler)
59 // The pipe signal handler must be installed before any other handlers are
60 // registered. This is because the Unix \ref RegisterHandlers function does
61 // not perform a sigaction() for SIGPIPE unless a one-shot handler is
62 // present, to allow long-lived processes (like lldb) to fully opt-out of
63 // llvm's SIGPIPE handling and ignore the signal safely.
64 sys::SetOneShotPipeSignalFunction(sys::DefaultOneShotPipeSignalHandler);
65 // Initialize the stack printer after installing the one-shot pipe signal
66 // handler, so we can perform a sigaction() for SIGPIPE on Unix if requested.
67 StackPrinter.emplace(args&: Argc, args&: Argv);
68 sys::PrintStackTraceOnErrorSignal(Argv0: Argv[0]);
69 install_out_of_memory_new_handler();
70
71#ifdef __MVS__
72
73 // We use UTF-8 as the internal character encoding. On z/OS, all external
74 // output is encoded in EBCDIC. In order to be able to read all
75 // error messages, we turn conversion to EBCDIC on for stderr fd.
76 std::string Banner = std::string(Argv[0]) + ": ";
77 ExitOnError ExitOnErr(Banner);
78
79 // If turning on conversion for stderr fails then the error message
80 // may be garbled. There is no solution to this problem.
81 ExitOnErr(errorCodeToError(llvm::enableAutoConversion(STDERR_FILENO)));
82 ExitOnErr(errorCodeToError(llvm::enableAutoConversion(STDOUT_FILENO)));
83#endif
84
85#ifdef _WIN32
86 // We use UTF-8 as the internal character encoding. On Windows,
87 // arguments passed to main() may not be encoded in UTF-8. In order
88 // to reliably detect encoding of command line arguments, we use an
89 // Windows API to obtain arguments, convert them to UTF-8, and then
90 // write them back to the Argv vector.
91 //
92 // There's probably other way to do the same thing (e.g. using
93 // wmain() instead of main()), but this way seems less intrusive
94 // than that.
95 std::string Banner = std::string(Argv[0]) + ": ";
96 ExitOnError ExitOnErr(Banner);
97
98 ExitOnErr(errorCodeToError(windows::GetCommandLineArguments(Args, Alloc)));
99
100 // GetCommandLineArguments doesn't terminate the vector with a
101 // nullptr. Do it to make it compatible with the real argv.
102 Args.push_back(nullptr);
103
104 Argc = Args.size() - 1;
105 Argv = Args.data();
106#endif
107}
108
109InitLLVM::~InitLLVM() {
110 CleanupStdHandles(Cookie: nullptr);
111 llvm_shutdown();
112}
113