src/llvm/lib/Support/ErrorHandling.cpp

   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
  39 using namespace llvm;
  40
  41 static fatal_error_handler_t ErrorHandler = nullptr;
  42 static void *ErrorHandlerUserData = nullptr;
  43
  44 static sys::Mutex ErrorHandlerMutex;
  45
  46 void 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
  54 void llvm::remove_fatal_error_handler() {
  55   llvm::MutexGuard Lock(ErrorHandlerMutex);
  56   ErrorHandler = nullptr;
  57   ErrorHandlerUserData = nullptr;
  58 }
  59
  60 void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) {
  61   report_fatal_error(Twine(Reason), GenCrashDiag);
  62 }
  63
  64 void llvm::report_fatal_error(const std::string &Reason, bool GenCrashDiag) {
  65   report_fatal_error(Twine(Reason), GenCrashDiag);
  66 }
  67
  68 void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) {
  69   report_fatal_error(Twine(Reason), GenCrashDiag);
  70 }
  71
  72 void 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
 105 void 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
 124 static 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
 131 void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) {
 132   install_fatal_error_handler(bindingsErrorHandler,
 133                               LLVM_EXTENSION reinterpret_cast<void *>(Handler));
 134 }
 135
 136 void 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
 149 std::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