llvm/lib/Support/InitLLVM.cpp

   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 }