ErrorHandling.cpp revision 276479 
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/Support/ErrorHandling.h"
16#include "llvm-c/Core.h"
17#include "llvm/ADT/SmallVector.h"
18#include "llvm/ADT/Twine.h"
19#include "llvm/Config/config.h"
20#include "llvm/Support/Debug.h"
21#include "llvm/Support/Errc.h"
22#include "llvm/Support/Signals.h"
23#include "llvm/Support/Mutex.h"
24#include "llvm/Support/MutexGuard.h"
25#include "llvm/Support/Threading.h"
26#include "llvm/Support/WindowsError.h"
27#include "llvm/Support/raw_ostream.h"
28#include <cassert>
29#include <cstdlib>
30
31#if defined(HAVE_UNISTD_H)
32# include <unistd.h>
33#endif
34#if defined(_MSC_VER)
35# include <io.h>
36# include <fcntl.h>
37#endif
38
39using namespace llvm;
40
41static fatal_error_handler_t ErrorHandler = nullptr;
42static void *ErrorHandlerUserData = nullptr;
43
44static sys::Mutex ErrorHandlerMutex;
45
46void llvm::install_fatal_error_handler(fatal_error_handler_t handler,
47                                       void *user_data) {
48  llvm::MutexGuard Lock(ErrorHandlerMutex);
49  assert(!ErrorHandler && "Error handler already registered!\n");
50  ErrorHandler = handler;
51  ErrorHandlerUserData = user_data;
52}
53
54void llvm::remove_fatal_error_handler() {
55  llvm::MutexGuard Lock(ErrorHandlerMutex);
56  ErrorHandler = nullptr;
57  ErrorHandlerUserData = nullptr;
58}
59
60void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) {
61  report_fatal_error(Twine(Reason), GenCrashDiag);
62}
63
64void llvm::report_fatal_error(const std::string &Reason, bool GenCrashDiag) {
65  report_fatal_error(Twine(Reason), GenCrashDiag);
66}
67
68void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) {
69  report_fatal_error(Twine(Reason), GenCrashDiag);
70}
71
72void llvm::report_fatal_error(const Twine &Reason, bool GenCrashDiag) {
73  llvm::fatal_error_handler_t handler = nullptr;
74  void* handlerData = nullptr;
75  {
76    // Only acquire the mutex while reading the handler, so as not to invoke a
77    // user-supplied callback under a lock.
78    llvm::MutexGuard Lock(ErrorHandlerMutex);
79    handler = ErrorHandler;
80    handlerData = ErrorHandlerUserData;
81  }
82
83  if (handler) {
84    handler(handlerData, Reason.str(), GenCrashDiag);
85  } else {
86    // Blast the result out to stderr.  We don't try hard to make sure this
87    // succeeds (e.g. handling EINTR) and we can't use errs() here because
88    // raw ostreams can call report_fatal_error.
89    SmallVector<char, 64> Buffer;
90    raw_svector_ostream OS(Buffer);
91    OS << "LLVM ERROR: " << Reason << "\n";
92    StringRef MessageStr = OS.str();
93    ssize_t written = ::write(2, MessageStr.data(), MessageStr.size());
94    (void)written; // If something went wrong, we deliberately just give up.
95  }
96
97  // If we reached here, we are failing ungracefully. Run the interrupt handlers
98  // to make sure any special cleanups get done, in particular that we remove
99  // files registered with RemoveFileOnSignal.
100  sys::RunInterruptHandlers();
101
102  exit(1);
103}
104
105void llvm::llvm_unreachable_internal(const char *msg, const char *file,
106                                     unsigned line) {
107  // This code intentionally doesn't call the ErrorHandler callback, because
108  // llvm_unreachable is intended to be used to indicate "impossible"
109  // situations, and not legitimate runtime errors.
110  if (msg)
111    dbgs() << msg << "\n";
112  dbgs() << "UNREACHABLE executed";
113  if (file)
114    dbgs() << " at " << file << ":" << line;
115  dbgs() << "!\n";
116  abort();
117#ifdef LLVM_BUILTIN_UNREACHABLE
118  // Windows systems and possibly others don't declare abort() to be noreturn,
119  // so use the unreachable builtin to avoid a Clang self-host warning.
120  LLVM_BUILTIN_UNREACHABLE;
121#endif
122}
123
124static void bindingsErrorHandler(void *user_data, const std::string& reason,
125                                 bool gen_crash_diag) {
126  LLVMFatalErrorHandler handler =
127      LLVM_EXTENSION reinterpret_cast<LLVMFatalErrorHandler>(user_data);
128  handler(reason.c_str());
129}
130
131void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) {
132  install_fatal_error_handler(bindingsErrorHandler,
133                              LLVM_EXTENSION reinterpret_cast<void *>(Handler));
134}
135
136void LLVMResetFatalErrorHandler() {
137  remove_fatal_error_handler();
138}
139
140#ifdef LLVM_ON_WIN32
141
142#include <winerror.h>
143
144// I'd rather not double the line count of the following.
145#define MAP_ERR_TO_COND(x, y)                                                  \
146  case x:                                                                      \
147    return make_error_code(errc::y)
148
149std::error_code llvm::mapWindowsError(unsigned EV) {
150  switch (EV) {
151    MAP_ERR_TO_COND(ERROR_ACCESS_DENIED, permission_denied);
152    MAP_ERR_TO_COND(ERROR_ALREADY_EXISTS, file_exists);
153    MAP_ERR_TO_COND(ERROR_BAD_UNIT, no_such_device);
154    MAP_ERR_TO_COND(ERROR_BUFFER_OVERFLOW, filename_too_long);
155    MAP_ERR_TO_COND(ERROR_BUSY, device_or_resource_busy);
156    MAP_ERR_TO_COND(ERROR_BUSY_DRIVE, device_or_resource_busy);
157    MAP_ERR_TO_COND(ERROR_CANNOT_MAKE, permission_denied);
158    MAP_ERR_TO_COND(ERROR_CANTOPEN, io_error);
159    MAP_ERR_TO_COND(ERROR_CANTREAD, io_error);
160    MAP_ERR_TO_COND(ERROR_CANTWRITE, io_error);
161    MAP_ERR_TO_COND(ERROR_CURRENT_DIRECTORY, permission_denied);
162    MAP_ERR_TO_COND(ERROR_DEV_NOT_EXIST, no_such_device);
163    MAP_ERR_TO_COND(ERROR_DEVICE_IN_USE, device_or_resource_busy);
164    MAP_ERR_TO_COND(ERROR_DIR_NOT_EMPTY, directory_not_empty);
165    MAP_ERR_TO_COND(ERROR_DIRECTORY, invalid_argument);
166    MAP_ERR_TO_COND(ERROR_DISK_FULL, no_space_on_device);
167    MAP_ERR_TO_COND(ERROR_FILE_EXISTS, file_exists);
168    MAP_ERR_TO_COND(ERROR_FILE_NOT_FOUND, no_such_file_or_directory);
169    MAP_ERR_TO_COND(ERROR_HANDLE_DISK_FULL, no_space_on_device);
170    MAP_ERR_TO_COND(ERROR_INVALID_ACCESS, permission_denied);
171    MAP_ERR_TO_COND(ERROR_INVALID_DRIVE, no_such_device);
172    MAP_ERR_TO_COND(ERROR_INVALID_FUNCTION, function_not_supported);
173    MAP_ERR_TO_COND(ERROR_INVALID_HANDLE, invalid_argument);
174    MAP_ERR_TO_COND(ERROR_INVALID_NAME, invalid_argument);
175    MAP_ERR_TO_COND(ERROR_LOCK_VIOLATION, no_lock_available);
176    MAP_ERR_TO_COND(ERROR_LOCKED, no_lock_available);
177    MAP_ERR_TO_COND(ERROR_NEGATIVE_SEEK, invalid_argument);
178    MAP_ERR_TO_COND(ERROR_NOACCESS, permission_denied);
179    MAP_ERR_TO_COND(ERROR_NOT_ENOUGH_MEMORY, not_enough_memory);
180    MAP_ERR_TO_COND(ERROR_NOT_READY, resource_unavailable_try_again);
181    MAP_ERR_TO_COND(ERROR_OPEN_FAILED, io_error);
182    MAP_ERR_TO_COND(ERROR_OPEN_FILES, device_or_resource_busy);
183    MAP_ERR_TO_COND(ERROR_OUTOFMEMORY, not_enough_memory);
184    MAP_ERR_TO_COND(ERROR_PATH_NOT_FOUND, no_such_file_or_directory);
185    MAP_ERR_TO_COND(ERROR_BAD_NETPATH, no_such_file_or_directory);
186    MAP_ERR_TO_COND(ERROR_READ_FAULT, io_error);
187    MAP_ERR_TO_COND(ERROR_RETRY, resource_unavailable_try_again);
188    MAP_ERR_TO_COND(ERROR_SEEK, io_error);
189    MAP_ERR_TO_COND(ERROR_SHARING_VIOLATION, permission_denied);
190    MAP_ERR_TO_COND(ERROR_TOO_MANY_OPEN_FILES, too_many_files_open);
191    MAP_ERR_TO_COND(ERROR_WRITE_FAULT, io_error);
192    MAP_ERR_TO_COND(ERROR_WRITE_PROTECT, permission_denied);
193    MAP_ERR_TO_COND(WSAEACCES, permission_denied);
194    MAP_ERR_TO_COND(WSAEBADF, bad_file_descriptor);
195    MAP_ERR_TO_COND(WSAEFAULT, bad_address);
196    MAP_ERR_TO_COND(WSAEINTR, interrupted);
197    MAP_ERR_TO_COND(WSAEINVAL, invalid_argument);
198    MAP_ERR_TO_COND(WSAEMFILE, too_many_files_open);
199    MAP_ERR_TO_COND(WSAENAMETOOLONG, filename_too_long);
200  default:
201    return std::error_code(EV, std::system_category());
202  }
203}
204
205#endif
206