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