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

source code of llvm/lib/Support/InitLLVM.cpp