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/Signals.h" 24 #include "llvm/Support/Threading.h" 25 #include "llvm/Support/WindowsError.h" 26 #include "llvm/Support/raw_ostream.h" 27 #include <cassert> 28 #include <cstdlib> 29 #include <mutex> 30 #include <new> 31 32 #if defined(HAVE_UNISTD_H) 33 # include <unistd.h> 34 #endif 35 #if defined(_MSC_VER) 36 # include <io.h> 37 # include <fcntl.h> 38 #endif 39 40 using namespace llvm; 41 42 static fatal_error_handler_t ErrorHandler = nullptr; 43 static void *ErrorHandlerUserData = nullptr; 44 45 static fatal_error_handler_t BadAllocErrorHandler = nullptr; 46 static void *BadAllocErrorHandlerUserData = nullptr; 47 48 // Mutexes to synchronize installing error handlers and calling error handlers. 49 // Do not use ManagedStatic, or that may allocate memory while attempting to 50 // report an OOM. 51 static std::mutex ErrorHandlerMutex; 52 static std::mutex BadAllocErrorHandlerMutex; 53 54 void llvm::install_fatal_error_handler(fatal_error_handler_t handler, 55 void *user_data) { 56 std::lock_guard<std::mutex> Lock(ErrorHandlerMutex); 57 assert(!ErrorHandler && "Error handler already registered!\n"); 58 ErrorHandler = handler; 59 ErrorHandlerUserData = user_data; 60 } 61 62 void llvm::remove_fatal_error_handler() { 63 std::lock_guard<std::mutex> Lock(ErrorHandlerMutex); 64 ErrorHandler = nullptr; 65 ErrorHandlerUserData = nullptr; 66 } 67 68 void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) { 69 report_fatal_error(Twine(Reason), GenCrashDiag); 70 } 71 72 void llvm::report_fatal_error(const std::string &Reason, bool GenCrashDiag) { 73 report_fatal_error(Twine(Reason), GenCrashDiag); 74 } 75 76 void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) { 77 report_fatal_error(Twine(Reason), GenCrashDiag); 78 } 79 80 void llvm::report_fatal_error(const Twine &Reason, bool GenCrashDiag) { 81 llvm::fatal_error_handler_t handler = nullptr; 82 void* handlerData = nullptr; 83 { 84 // Only acquire the mutex while reading the handler, so as not to invoke a 85 // user-supplied callback under a lock. 86 std::lock_guard<std::mutex> Lock(ErrorHandlerMutex); 87 handler = ErrorHandler; 88 handlerData = ErrorHandlerUserData; 89 } 90 91 if (handler) { 92 handler(handlerData, Reason.str(), GenCrashDiag); 93 } else { 94 // Blast the result out to stderr. We don't try hard to make sure this 95 // succeeds (e.g. handling EINTR) and we can't use errs() here because 96 // raw ostreams can call report_fatal_error. 97 SmallVector<char, 64> Buffer; 98 raw_svector_ostream OS(Buffer); 99 OS << "LLVM ERROR: " << Reason << "\n"; 100 StringRef MessageStr = OS.str(); 101 ssize_t written = ::write(2, MessageStr.data(), MessageStr.size()); 102 (void)written; // If something went wrong, we deliberately just give up. 103 } 104 105 // If we reached here, we are failing ungracefully. Run the interrupt handlers 106 // to make sure any special cleanups get done, in particular that we remove 107 // files registered with RemoveFileOnSignal. 108 sys::RunInterruptHandlers(); 109 110 exit(1); 111 } 112 113 void llvm::install_bad_alloc_error_handler(fatal_error_handler_t handler, 114 void *user_data) { 115 std::lock_guard<std::mutex> Lock(BadAllocErrorHandlerMutex); 116 assert(!ErrorHandler && "Bad alloc error handler already registered!\n"); 117 BadAllocErrorHandler = handler; 118 BadAllocErrorHandlerUserData = user_data; 119 } 120 121 void llvm::remove_bad_alloc_error_handler() { 122 std::lock_guard<std::mutex> Lock(BadAllocErrorHandlerMutex); 123 BadAllocErrorHandler = nullptr; 124 BadAllocErrorHandlerUserData = nullptr; 125 } 126 127 void llvm::report_bad_alloc_error(const char *Reason, bool GenCrashDiag) { 128 fatal_error_handler_t Handler = nullptr; 129 void *HandlerData = nullptr; 130 { 131 // Only acquire the mutex while reading the handler, so as not to invoke a 132 // user-supplied callback under a lock. 133 std::lock_guard<std::mutex> Lock(BadAllocErrorHandlerMutex); 134 Handler = BadAllocErrorHandler; 135 HandlerData = BadAllocErrorHandlerUserData; 136 } 137 138 if (Handler) { 139 Handler(HandlerData, Reason, GenCrashDiag); 140 llvm_unreachable("bad alloc handler should not return"); 141 } 142 143 #ifdef LLVM_ENABLE_EXCEPTIONS 144 // If exceptions are enabled, make OOM in malloc look like OOM in new. 145 throw std::bad_alloc(); 146 #else 147 // Don't call the normal error handler. It may allocate memory. Directly write 148 // an OOM to stderr and abort. 149 char OOMMessage[] = "LLVM ERROR: out of memory\n"; 150 (void)::write(2, OOMMessage, strlen(OOMMessage)); 151 abort(); 152 #endif 153 } 154 155 void llvm::llvm_unreachable_internal(const char *msg, const char *file, 156 unsigned line) { 157 // This code intentionally doesn't call the ErrorHandler callback, because 158 // llvm_unreachable is intended to be used to indicate "impossible" 159 // situations, and not legitimate runtime errors. 160 if (msg) 161 dbgs() << msg << "\n"; 162 dbgs() << "UNREACHABLE executed"; 163 if (file) 164 dbgs() << " at " << file << ":" << line; 165 dbgs() << "!\n"; 166 abort(); 167 #ifdef LLVM_BUILTIN_UNREACHABLE 168 // Windows systems and possibly others don't declare abort() to be noreturn, 169 // so use the unreachable builtin to avoid a Clang self-host warning. 170 LLVM_BUILTIN_UNREACHABLE; 171 #endif 172 } 173 174 static void bindingsErrorHandler(void *user_data, const std::string& reason, 175 bool gen_crash_diag) { 176 LLVMFatalErrorHandler handler = 177 LLVM_EXTENSION reinterpret_cast<LLVMFatalErrorHandler>(user_data); 178 handler(reason.c_str()); 179 } 180 181 void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) { 182 install_fatal_error_handler(bindingsErrorHandler, 183 LLVM_EXTENSION reinterpret_cast<void *>(Handler)); 184 } 185 186 void LLVMResetFatalErrorHandler() { 187 remove_fatal_error_handler(); 188 } 189 190 #ifdef LLVM_ON_WIN32 191 192 #include <winerror.h> 193 194 // I'd rather not double the line count of the following. 195 #define MAP_ERR_TO_COND(x, y) \ 196 case x: \ 197 return make_error_code(errc::y) 198 199 std::error_code llvm::mapWindowsError(unsigned EV) { 200 switch (EV) { 201 MAP_ERR_TO_COND(ERROR_ACCESS_DENIED, permission_denied); 202 MAP_ERR_TO_COND(ERROR_ALREADY_EXISTS, file_exists); 203 MAP_ERR_TO_COND(ERROR_BAD_UNIT, no_such_device); 204 MAP_ERR_TO_COND(ERROR_BUFFER_OVERFLOW, filename_too_long); 205 MAP_ERR_TO_COND(ERROR_BUSY, device_or_resource_busy); 206 MAP_ERR_TO_COND(ERROR_BUSY_DRIVE, device_or_resource_busy); 207 MAP_ERR_TO_COND(ERROR_CANNOT_MAKE, permission_denied); 208 MAP_ERR_TO_COND(ERROR_CANTOPEN, io_error); 209 MAP_ERR_TO_COND(ERROR_CANTREAD, io_error); 210 MAP_ERR_TO_COND(ERROR_CANTWRITE, io_error); 211 MAP_ERR_TO_COND(ERROR_CURRENT_DIRECTORY, permission_denied); 212 MAP_ERR_TO_COND(ERROR_DEV_NOT_EXIST, no_such_device); 213 MAP_ERR_TO_COND(ERROR_DEVICE_IN_USE, device_or_resource_busy); 214 MAP_ERR_TO_COND(ERROR_DIR_NOT_EMPTY, directory_not_empty); 215 MAP_ERR_TO_COND(ERROR_DIRECTORY, invalid_argument); 216 MAP_ERR_TO_COND(ERROR_DISK_FULL, no_space_on_device); 217 MAP_ERR_TO_COND(ERROR_FILE_EXISTS, file_exists); 218 MAP_ERR_TO_COND(ERROR_FILE_NOT_FOUND, no_such_file_or_directory); 219 MAP_ERR_TO_COND(ERROR_HANDLE_DISK_FULL, no_space_on_device); 220 MAP_ERR_TO_COND(ERROR_INVALID_ACCESS, permission_denied); 221 MAP_ERR_TO_COND(ERROR_INVALID_DRIVE, no_such_device); 222 MAP_ERR_TO_COND(ERROR_INVALID_FUNCTION, function_not_supported); 223 MAP_ERR_TO_COND(ERROR_INVALID_HANDLE, invalid_argument); 224 MAP_ERR_TO_COND(ERROR_INVALID_NAME, invalid_argument); 225 MAP_ERR_TO_COND(ERROR_LOCK_VIOLATION, no_lock_available); 226 MAP_ERR_TO_COND(ERROR_LOCKED, no_lock_available); 227 MAP_ERR_TO_COND(ERROR_NEGATIVE_SEEK, invalid_argument); 228 MAP_ERR_TO_COND(ERROR_NOACCESS, permission_denied); 229 MAP_ERR_TO_COND(ERROR_NOT_ENOUGH_MEMORY, not_enough_memory); 230 MAP_ERR_TO_COND(ERROR_NOT_READY, resource_unavailable_try_again); 231 MAP_ERR_TO_COND(ERROR_OPEN_FAILED, io_error); 232 MAP_ERR_TO_COND(ERROR_OPEN_FILES, device_or_resource_busy); 233 MAP_ERR_TO_COND(ERROR_OUTOFMEMORY, not_enough_memory); 234 MAP_ERR_TO_COND(ERROR_PATH_NOT_FOUND, no_such_file_or_directory); 235 MAP_ERR_TO_COND(ERROR_BAD_NETPATH, no_such_file_or_directory); 236 MAP_ERR_TO_COND(ERROR_READ_FAULT, io_error); 237 MAP_ERR_TO_COND(ERROR_RETRY, resource_unavailable_try_again); 238 MAP_ERR_TO_COND(ERROR_SEEK, io_error); 239 MAP_ERR_TO_COND(ERROR_SHARING_VIOLATION, permission_denied); 240 MAP_ERR_TO_COND(ERROR_TOO_MANY_OPEN_FILES, too_many_files_open); 241 MAP_ERR_TO_COND(ERROR_WRITE_FAULT, io_error); 242 MAP_ERR_TO_COND(ERROR_WRITE_PROTECT, permission_denied); 243 MAP_ERR_TO_COND(WSAEACCES, permission_denied); 244 MAP_ERR_TO_COND(WSAEBADF, bad_file_descriptor); 245 MAP_ERR_TO_COND(WSAEFAULT, bad_address); 246 MAP_ERR_TO_COND(WSAEINTR, interrupted); 247 MAP_ERR_TO_COND(WSAEINVAL, invalid_argument); 248 MAP_ERR_TO_COND(WSAEMFILE, too_many_files_open); 249 MAP_ERR_TO_COND(WSAENAMETOOLONG, filename_too_long); 250 default: 251 return std::error_code(EV, std::system_category()); 252 } 253 } 254 255 #endif 256