ErrorHandling.cpp revision 212904 
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/System/Signals.h"
20#include "llvm/System/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
34using namespace llvm;
35using namespace std;
36
37static fatal_error_handler_t ErrorHandler = 0;
38static void *ErrorHandlerUserData = 0;
39
40void 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
49void llvm::remove_fatal_error_handler() {
50  ErrorHandler = 0;
51}
52
53void llvm::report_fatal_error(const char *Reason) {
54  report_fatal_error(Twine(Reason));
55}
56
57void llvm::report_fatal_error(const std::string &Reason) {
58  report_fatal_error(Twine(Reason));
59}
60
61void llvm::report_fatal_error(const Twine &Reason) {
62  if (ErrorHandler) {
63    ErrorHandler(ErrorHandlerUserData, Reason.str());
64  } else {
65    // Blast the result out to stderr.  We don't try hard to make sure this
66    // succeeds (e.g. handling EINTR) and we can't use errs() here because
67    // raw ostreams can call report_fatal_error.
68    SmallVector<char, 64> Buffer;
69    raw_svector_ostream OS(Buffer);
70    OS << "LLVM ERROR: " << Reason << "\n";
71    StringRef MessageStr = OS.str();
72    (void)::write(2, MessageStr.data(), MessageStr.size());
73  }
74
75  // If we reached here, we are failing ungracefully. Run the interrupt handlers
76  // to make sure any special cleanups get done, in particular that we remove
77  // files registered with RemoveFileOnSignal.
78  sys::RunInterruptHandlers();
79
80  exit(1);
81}
82
83void llvm::llvm_unreachable_internal(const char *msg, const char *file,
84                                     unsigned line) {
85  // This code intentionally doesn't call the ErrorHandler callback, because
86  // llvm_unreachable is intended to be used to indicate "impossible"
87  // situations, and not legitimate runtime errors.
88  if (msg)
89    dbgs() << msg << "\n";
90  dbgs() << "UNREACHABLE executed";
91  if (file)
92    dbgs() << " at " << file << ":" << line;
93  dbgs() << "!\n";
94  abort();
95}
96