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
34using namespace llvm;
35
36static fatal_error_handler_t ErrorHandler = 0;
37static void *ErrorHandlerUserData = 0;
38
39void llvm::install_fatal_error_handler(fatal_error_handler_t handler,
40                                       void *user_data) {
41  assert(!llvm_is_multithreaded() &&
42         "Cannot register error handlers after starting multithreaded mode!\n");
43  assert(!ErrorHandler && "Error handler already registered!\n");
44  ErrorHandler = handler;
45  ErrorHandlerUserData = user_data;
46}
47
48void llvm::remove_fatal_error_handler() {
49  ErrorHandler = 0;
50}
51
52void llvm::report_fatal_error(const char *Reason) {
53  report_fatal_error(Twine(Reason));
54}
55
56void llvm::report_fatal_error(const std::string &Reason) {
57  report_fatal_error(Twine(Reason));
58}
59
60void llvm::report_fatal_error(StringRef Reason) {
61  report_fatal_error(Twine(Reason));
62}
63
64void llvm::report_fatal_error(const Twine &Reason) {
65  if (ErrorHandler) {
66    ErrorHandler(ErrorHandlerUserData, Reason.str());
67  } else {
68    // Blast the result out to stderr.  We don't try hard to make sure this
69    // succeeds (e.g. handling EINTR) and we can't use errs() here because
70    // raw ostreams can call report_fatal_error.
71    SmallVector<char, 64> Buffer;
72    raw_svector_ostream OS(Buffer);
73    OS << "LLVM ERROR: " << Reason << "\n";
74    StringRef MessageStr = OS.str();
75    ssize_t written = ::write(2, MessageStr.data(), MessageStr.size());
76    (void)written; // If something went wrong, we deliberately just give up.
77  }
78
79  // If we reached here, we are failing ungracefully. Run the interrupt handlers
80  // to make sure any special cleanups get done, in particular that we remove
81  // files registered with RemoveFileOnSignal.
82  sys::RunInterruptHandlers();
83
84  exit(1);
85}
86
87void llvm::llvm_unreachable_internal(const char *msg, const char *file,
88                                     unsigned line) {
89  // This code intentionally doesn't call the ErrorHandler callback, because
90  // llvm_unreachable is intended to be used to indicate "impossible"
91  // situations, and not legitimate runtime errors.
92  if (msg)
93    dbgs() << msg << "\n";
94  dbgs() << "UNREACHABLE executed";
95  if (file)
96    dbgs() << " at " << file << ":" << line;
97  dbgs() << "!\n";
98  abort();
99}
100