ErrorHandling.cpp revision 309124 
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/ErrorHandling.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/Error.h"
23#include "llvm/Support/ManagedStatic.h"
24#include "llvm/Support/Mutex.h"
25#include "llvm/Support/MutexGuard.h"
26#include "llvm/Support/Signals.h"
27#include "llvm/Support/Threading.h"
28#include "llvm/Support/WindowsError.h"
29#include "llvm/Support/raw_ostream.h"
30#include <cassert>
31#include <cstdlib>
32
33#if defined(HAVE_UNISTD_H)
34# include <unistd.h>
35#endif
36#if defined(_MSC_VER)
37# include <io.h>
38# include <fcntl.h>
39#endif
40
41using namespace llvm;
42
43static fatal_error_handler_t ErrorHandler = nullptr;
44static void *ErrorHandlerUserData = nullptr;
45
46static ManagedStatic<sys::Mutex> ErrorHandlerMutex;
47
48void llvm::install_fatal_error_handler(fatal_error_handler_t handler,
49                                       void *user_data) {
50  llvm::MutexGuard Lock(*ErrorHandlerMutex);
51  assert(!ErrorHandler && "Error handler already registered!\n");
52  ErrorHandler = handler;
53  ErrorHandlerUserData = user_data;
54}
55
56void llvm::remove_fatal_error_handler() {
57  llvm::MutexGuard Lock(*ErrorHandlerMutex);
58  ErrorHandler = nullptr;
59  ErrorHandlerUserData = nullptr;
60}
61
62void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) {
63  report_fatal_error(Twine(Reason), GenCrashDiag);
64}
65
66void llvm::report_fatal_error(const std::string &Reason, bool GenCrashDiag) {
67  report_fatal_error(Twine(Reason), GenCrashDiag);
68}
69
70void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) {
71  report_fatal_error(Twine(Reason), GenCrashDiag);
72}
73
74void llvm::report_fatal_error(const Twine &Reason, bool GenCrashDiag) {
75  llvm::fatal_error_handler_t handler = nullptr;
76  void* handlerData = nullptr;
77  {
78    // Only acquire the mutex while reading the handler, so as not to invoke a
79    // user-supplied callback under a lock.
80    llvm::MutexGuard Lock(*ErrorHandlerMutex);
81    handler = ErrorHandler;
82    handlerData = ErrorHandlerUserData;
83  }
84
85  if (handler) {
86    handler(handlerData, Reason.str(), GenCrashDiag);
87  } else {
88    // Blast the result out to stderr.  We don't try hard to make sure this
89    // succeeds (e.g. handling EINTR) and we can't use errs() here because
90    // raw ostreams can call report_fatal_error.
91    SmallVector<char, 64> Buffer;
92    raw_svector_ostream OS(Buffer);
93    OS << "LLVM ERROR: " << Reason << "\n";
94    StringRef MessageStr = OS.str();
95    ssize_t written = ::write(2, MessageStr.data(), MessageStr.size());
96    (void)written; // If something went wrong, we deliberately just give up.
97  }
98
99  // If we reached here, we are failing ungracefully. Run the interrupt handlers
100  // to make sure any special cleanups get done, in particular that we remove
101  // files registered with RemoveFileOnSignal.
102  sys::RunInterruptHandlers();
103
104  exit(1);
105}
106
107void llvm::llvm_unreachable_internal(const char *msg, const char *file,
108                                     unsigned line) {
109  // This code intentionally doesn't call the ErrorHandler callback, because
110  // llvm_unreachable is intended to be used to indicate "impossible"
111  // situations, and not legitimate runtime errors.
112  if (msg)
113    dbgs() << msg << "\n";
114  dbgs() << "UNREACHABLE executed";
115  if (file)
116    dbgs() << " at " << file << ":" << line;
117  dbgs() << "!\n";
118  abort();
119#ifdef LLVM_BUILTIN_UNREACHABLE
120  // Windows systems and possibly others don't declare abort() to be noreturn,
121  // so use the unreachable builtin to avoid a Clang self-host warning.
122  LLVM_BUILTIN_UNREACHABLE;
123#endif
124}
125
126static void bindingsErrorHandler(void *user_data, const std::string& reason,
127                                 bool gen_crash_diag) {
128  LLVMFatalErrorHandler handler =
129      LLVM_EXTENSION reinterpret_cast<LLVMFatalErrorHandler>(user_data);
130  handler(reason.c_str());
131}
132
133void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) {
134  install_fatal_error_handler(bindingsErrorHandler,
135                              LLVM_EXTENSION reinterpret_cast<void *>(Handler));
136}
137
138void LLVMResetFatalErrorHandler() {
139  remove_fatal_error_handler();
140}
141
142#ifdef LLVM_ON_WIN32
143
144#include <winerror.h>
145
146// I'd rather not double the line count of the following.
147#define MAP_ERR_TO_COND(x, y)                                                  \
148  case x:                                                                      \
149    return make_error_code(errc::y)
150
151std::error_code llvm::mapWindowsError(unsigned EV) {
152  switch (EV) {
153    MAP_ERR_TO_COND(ERROR_ACCESS_DENIED, permission_denied);
154    MAP_ERR_TO_COND(ERROR_ALREADY_EXISTS, file_exists);
155    MAP_ERR_TO_COND(ERROR_BAD_UNIT, no_such_device);
156    MAP_ERR_TO_COND(ERROR_BUFFER_OVERFLOW, filename_too_long);
157    MAP_ERR_TO_COND(ERROR_BUSY, device_or_resource_busy);
158    MAP_ERR_TO_COND(ERROR_BUSY_DRIVE, device_or_resource_busy);
159    MAP_ERR_TO_COND(ERROR_CANNOT_MAKE, permission_denied);
160    MAP_ERR_TO_COND(ERROR_CANTOPEN, io_error);
161    MAP_ERR_TO_COND(ERROR_CANTREAD, io_error);
162    MAP_ERR_TO_COND(ERROR_CANTWRITE, io_error);
163    MAP_ERR_TO_COND(ERROR_CURRENT_DIRECTORY, permission_denied);
164    MAP_ERR_TO_COND(ERROR_DEV_NOT_EXIST, no_such_device);
165    MAP_ERR_TO_COND(ERROR_DEVICE_IN_USE, device_or_resource_busy);
166    MAP_ERR_TO_COND(ERROR_DIR_NOT_EMPTY, directory_not_empty);
167    MAP_ERR_TO_COND(ERROR_DIRECTORY, invalid_argument);
168    MAP_ERR_TO_COND(ERROR_DISK_FULL, no_space_on_device);
169    MAP_ERR_TO_COND(ERROR_FILE_EXISTS, file_exists);
170    MAP_ERR_TO_COND(ERROR_FILE_NOT_FOUND, no_such_file_or_directory);
171    MAP_ERR_TO_COND(ERROR_HANDLE_DISK_FULL, no_space_on_device);
172    MAP_ERR_TO_COND(ERROR_INVALID_ACCESS, permission_denied);
173    MAP_ERR_TO_COND(ERROR_INVALID_DRIVE, no_such_device);
174    MAP_ERR_TO_COND(ERROR_INVALID_FUNCTION, function_not_supported);
175    MAP_ERR_TO_COND(ERROR_INVALID_HANDLE, invalid_argument);
176    MAP_ERR_TO_COND(ERROR_INVALID_NAME, invalid_argument);
177    MAP_ERR_TO_COND(ERROR_LOCK_VIOLATION, no_lock_available);
178    MAP_ERR_TO_COND(ERROR_LOCKED, no_lock_available);
179    MAP_ERR_TO_COND(ERROR_NEGATIVE_SEEK, invalid_argument);
180    MAP_ERR_TO_COND(ERROR_NOACCESS, permission_denied);
181    MAP_ERR_TO_COND(ERROR_NOT_ENOUGH_MEMORY, not_enough_memory);
182    MAP_ERR_TO_COND(ERROR_NOT_READY, resource_unavailable_try_again);
183    MAP_ERR_TO_COND(ERROR_OPEN_FAILED, io_error);
184    MAP_ERR_TO_COND(ERROR_OPEN_FILES, device_or_resource_busy);
185    MAP_ERR_TO_COND(ERROR_OUTOFMEMORY, not_enough_memory);
186    MAP_ERR_TO_COND(ERROR_PATH_NOT_FOUND, no_such_file_or_directory);
187    MAP_ERR_TO_COND(ERROR_BAD_NETPATH, no_such_file_or_directory);
188    MAP_ERR_TO_COND(ERROR_READ_FAULT, io_error);
189    MAP_ERR_TO_COND(ERROR_RETRY, resource_unavailable_try_again);
190    MAP_ERR_TO_COND(ERROR_SEEK, io_error);
191    MAP_ERR_TO_COND(ERROR_SHARING_VIOLATION, permission_denied);
192    MAP_ERR_TO_COND(ERROR_TOO_MANY_OPEN_FILES, too_many_files_open);
193    MAP_ERR_TO_COND(ERROR_WRITE_FAULT, io_error);
194    MAP_ERR_TO_COND(ERROR_WRITE_PROTECT, permission_denied);
195    MAP_ERR_TO_COND(WSAEACCES, permission_denied);
196    MAP_ERR_TO_COND(WSAEBADF, bad_file_descriptor);
197    MAP_ERR_TO_COND(WSAEFAULT, bad_address);
198    MAP_ERR_TO_COND(WSAEINTR, interrupted);
199    MAP_ERR_TO_COND(WSAEINVAL, invalid_argument);
200    MAP_ERR_TO_COND(WSAEMFILE, too_many_files_open);
201    MAP_ERR_TO_COND(WSAENAMETOOLONG, filename_too_long);
202  default:
203    return std::error_code(EV, std::system_category());
204  }
205}
206
207#endif
208