xref: /freebsd/contrib/llvm-project/llvm/lib/Support/InitLLVM.cpp (revision a90b9d0159070121c221b966469c3e36d912bf82)
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 
26 void 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 
36 using namespace llvm;
37 using namespace llvm::sys;
38 
39 InitLLVM::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(Argc, Argv);
60   sys::PrintStackTraceOnErrorSignal(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 
101 InitLLVM::~InitLLVM() {
102 #ifdef __MVS__
103   CleanupStdHandles(nullptr);
104 #endif
105   llvm_shutdown();
106 }
107