lib/Support/ErrorHandling.cpp

   1 //===- lib/Support/ErrorHandling.cpp - Callbacks for errors ---------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file defines an API used to indicate fatal error conditions.  Non-fatal
  11 // errors (most of them) should be handled through LLVMContext.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "llvm/ADT/Twine.h"
  16 #include "llvm/Support/Debug.h"
  17 #include "llvm/Support/ErrorHandling.h"
  18 #include "llvm/Support/raw_ostream.h"
  19 #include "llvm/Support/Signals.h"
  20 #include "llvm/Support/Threading.h"
  21 #include "llvm/ADT/SmallVector.h"
  22 #include "llvm/Config/config.h"
  23 #include <cassert>
  24 #include <cstdlib>
  25
  26 #if defined(HAVE_UNISTD_H)
  27 # include <unistd.h>
  28 #endif
  29 #if defined(_MSC_VER)
  30 # include <io.h>
  31 # include <fcntl.h>
  32 #endif
  33
  34 using namespace llvm;
  35 using namespace std;
  36
  37 static fatal_error_handler_t ErrorHandler = 0;
  38 static void *ErrorHandlerUserData = 0;
  39
  40 void llvm::install_fatal_error_handler(fatal_error_handler_t handler,
  41                                        void *user_data) {
  42   assert(!llvm_is_multithreaded() &&
  43          "Cannot register error handlers after starting multithreaded mode!\n");
  44   assert(!ErrorHandler && "Error handler already registered!\n");
  45   ErrorHandler = handler;
  46   ErrorHandlerUserData = user_data;
  47 }
  48
  49 void llvm::remove_fatal_error_handler() {
  50   ErrorHandler = 0;
  51 }
  52
  53 void llvm::report_fatal_error(const char *Reason) {
  54   report_fatal_error(Twine(Reason));
  55 }
  56
  57 void llvm::report_fatal_error(const std::string &Reason) {
  58   report_fatal_error(Twine(Reason));
  59 }
  60
  61 void llvm::report_fatal_error(StringRef Reason) {
  62   report_fatal_error(Twine(Reason));
  63 }
  64
  65 void llvm::report_fatal_error(const Twine &Reason) {
  66   if (ErrorHandler) {
  67     ErrorHandler(ErrorHandlerUserData, Reason.str());
  68   } else {
  69     // Blast the result out to stderr.  We don't try hard to make sure this
  70     // succeeds (e.g. handling EINTR) and we can't use errs() here because
  71     // raw ostreams can call report_fatal_error.
  72     SmallVector<char, 64> Buffer;
  73     raw_svector_ostream OS(Buffer);
  74     OS << "LLVM ERROR: " << Reason << "\n";
  75     StringRef MessageStr = OS.str();
  76     ssize_t written = ::write(2, MessageStr.data(), MessageStr.size());
  77     (void)written; // If something went wrong, we deliberately just give up.
  78   }
  79
  80   // If we reached here, we are failing ungracefully. Run the interrupt handlers
  81   // to make sure any special cleanups get done, in particular that we remove
  82   // files registered with RemoveFileOnSignal.
  83   sys::RunInterruptHandlers();
  84
  85   exit(1);
  86 }
  87
  88 void llvm::llvm_unreachable_internal(const char *msg, const char *file,
  89                                      unsigned line) {
  90   // This code intentionally doesn't call the ErrorHandler callback, because
  91   // llvm_unreachable is intended to be used to indicate "impossible"
  92   // situations, and not legitimate runtime errors.
  93   if (msg)
  94     dbgs() << msg << "\n";
  95   dbgs() << "UNREACHABLE executed";
  96   if (file)
  97     dbgs() << " at " << file << ":" << line;
  98   dbgs() << "!\n";
  99   abort();
 100 }