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