374 lines · cpp
1//===- lib/Support/ErrorHandling.cpp - Callbacks for errors ---------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file defines an API used to indicate fatal error conditions. Non-fatal10// errors (most of them) should be handled through LLVMContext.11//12//===----------------------------------------------------------------------===//13 14#include "llvm/Support/ErrorHandling.h"15#include "llvm-c/ErrorHandling.h"16#include "llvm/ADT/SmallVector.h"17#include "llvm/ADT/Twine.h"18#include "llvm/Config/config.h"19#include "llvm/Config/llvm-config.h" // for LLVM_ENABLE_THREADS20#include "llvm/Support/Debug.h"21#include "llvm/Support/Errc.h"22#include "llvm/Support/Errno.h"23#include "llvm/Support/Error.h"24#include "llvm/Support/Process.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#include <mutex>32#include <new>33 34#if defined(HAVE_UNISTD_H)35# include <unistd.h>36#endif37#if defined(_WIN32)38# include <io.h>39# include <fcntl.h>40#endif41 42using namespace llvm;43 44static fatal_error_handler_t ErrorHandler = nullptr;45static void *ErrorHandlerUserData = nullptr;46 47static fatal_error_handler_t BadAllocErrorHandler = nullptr;48static void *BadAllocErrorHandlerUserData = nullptr;49 50#if LLVM_ENABLE_THREADS == 151// Mutexes to synchronize installing error handlers and calling error handlers.52// Do not use ManagedStatic, or that may allocate memory while attempting to53// report an OOM.54//55// This usage of std::mutex has to be conditionalized behind ifdefs because56// of this script:57// compiler-rt/lib/sanitizer_common/symbolizer/scripts/build_symbolizer.sh58// That script attempts to statically link the LLVM symbolizer library with the59// STL and hide all of its symbols with 'opt -internalize'. To reduce size, it60// cuts out the threading portions of the hermetic copy of libc++ that it61// builds. We can remove these ifdefs if that script goes away.62static std::mutex ErrorHandlerMutex;63static std::mutex BadAllocErrorHandlerMutex;64#endif65 66static bool write_retry(int fd, const char *buf, size_t count) {67 while (count > 0) {68 ssize_t written = sys::RetryAfterSignal(-1, ::write, fd, buf, count);69 if (written <= 0)70 return false;71 buf += written;72 count -= written;73 }74 return true;75}76 77void llvm::install_fatal_error_handler(fatal_error_handler_t handler,78 void *user_data) {79#if LLVM_ENABLE_THREADS == 180 std::lock_guard<std::mutex> Lock(ErrorHandlerMutex);81#endif82 assert(!ErrorHandler && "Error handler already registered!\n");83 ErrorHandler = handler;84 ErrorHandlerUserData = user_data;85}86 87void llvm::remove_fatal_error_handler() {88#if LLVM_ENABLE_THREADS == 189 std::lock_guard<std::mutex> Lock(ErrorHandlerMutex);90#endif91 ErrorHandler = nullptr;92 ErrorHandlerUserData = nullptr;93}94 95void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) {96 report_fatal_error(Twine(Reason), GenCrashDiag);97}98 99void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) {100 report_fatal_error(Twine(Reason), GenCrashDiag);101}102 103void llvm::report_fatal_error(const Twine &Reason, bool GenCrashDiag) {104 llvm::fatal_error_handler_t handler = nullptr;105 void* handlerData = nullptr;106 {107 // Only acquire the mutex while reading the handler, so as not to invoke a108 // user-supplied callback under a lock.109#if LLVM_ENABLE_THREADS == 1110 std::lock_guard<std::mutex> Lock(ErrorHandlerMutex);111#endif112 handler = ErrorHandler;113 handlerData = ErrorHandlerUserData;114 }115 116 if (handler) {117 handler(handlerData, Reason.str().c_str(), GenCrashDiag);118 } else {119 // Blast the result out to stderr. We don't try hard to make sure this120 // succeeds (e.g. handling EINTR) and we can't use errs() here because121 // raw ostreams can call report_fatal_error.122 SmallVector<char, 64> Buffer;123 raw_svector_ostream OS(Buffer);124 OS << "LLVM ERROR: " << Reason << "\n";125 StringRef MessageStr = OS.str();126 write_retry(2, MessageStr.data(), MessageStr.size());127 }128 129 // If we reached here, we are failing ungracefully. Run the interrupt handlers130 // to make sure any special cleanups get done, in particular that we remove131 // files registered with RemoveFileOnSignal.132 sys::RunInterruptHandlers();133 134 if (GenCrashDiag)135 abort();136 else137 exit(1);138}139 140void llvm::reportFatalInternalError(const char *reason) {141 report_fatal_error(reason, /*GenCrashDiag=*/true);142}143void llvm::reportFatalInternalError(StringRef reason) {144 report_fatal_error(reason, /*GenCrashDiag=*/true);145}146void llvm::reportFatalInternalError(const Twine &reason) {147 report_fatal_error(reason, /*GenCrashDiag=*/true);148}149void llvm::reportFatalUsageError(const char *reason) {150 report_fatal_error(reason, /*GenCrashDiag=*/false);151}152void llvm::reportFatalUsageError(StringRef reason) {153 report_fatal_error(reason, /*GenCrashDiag=*/false);154}155void llvm::reportFatalUsageError(const Twine &reason) {156 report_fatal_error(reason, /*GenCrashDiag=*/false);157}158 159void llvm::install_bad_alloc_error_handler(fatal_error_handler_t handler,160 void *user_data) {161#if LLVM_ENABLE_THREADS == 1162 std::lock_guard<std::mutex> Lock(BadAllocErrorHandlerMutex);163#endif164 assert(!BadAllocErrorHandler &&165 "Bad alloc error handler already registered!\n");166 BadAllocErrorHandler = handler;167 BadAllocErrorHandlerUserData = user_data;168}169 170void llvm::remove_bad_alloc_error_handler() {171#if LLVM_ENABLE_THREADS == 1172 std::lock_guard<std::mutex> Lock(BadAllocErrorHandlerMutex);173#endif174 BadAllocErrorHandler = nullptr;175 BadAllocErrorHandlerUserData = nullptr;176}177 178void llvm::report_bad_alloc_error(const char *Reason, bool GenCrashDiag) {179 fatal_error_handler_t Handler = nullptr;180 void *HandlerData = nullptr;181 {182 // Only acquire the mutex while reading the handler, so as not to invoke a183 // user-supplied callback under a lock.184#if LLVM_ENABLE_THREADS == 1185 std::lock_guard<std::mutex> Lock(BadAllocErrorHandlerMutex);186#endif187 Handler = BadAllocErrorHandler;188 HandlerData = BadAllocErrorHandlerUserData;189 }190 191 if (Handler) {192 Handler(HandlerData, Reason, GenCrashDiag);193 llvm_unreachable("bad alloc handler should not return");194 }195 196#ifdef LLVM_ENABLE_EXCEPTIONS197 // If exceptions are enabled, make OOM in malloc look like OOM in new.198 throw std::bad_alloc();199#else200 // Don't call the normal error handler. It may allocate memory. Directly write201 // an OOM to stderr and abort.202 const char *OOMMessage = "LLVM ERROR: out of memory\n";203 const char *Newline = "\n";204 write_retry(2, OOMMessage, strlen(OOMMessage));205 write_retry(2, Reason, strlen(Reason));206 write_retry(2, Newline, strlen(Newline));207 abort();208#endif209}210 211#ifdef LLVM_ENABLE_EXCEPTIONS212// Do not set custom new handler if exceptions are enabled. In this case OOM213// errors are handled by throwing 'std::bad_alloc'.214void llvm::install_out_of_memory_new_handler() {215}216#else217// Causes crash on allocation failure. It is called prior to the handler set by218// 'install_bad_alloc_error_handler'.219static void out_of_memory_new_handler() {220 llvm::report_bad_alloc_error("Allocation failed");221}222 223// Installs new handler that causes crash on allocation failure. It is called by224// InitLLVM.225void llvm::install_out_of_memory_new_handler() {226 std::new_handler old = std::set_new_handler(out_of_memory_new_handler);227 (void)old;228 assert((old == nullptr || old == out_of_memory_new_handler) &&229 "new-handler already installed");230}231#endif232 233void llvm::llvm_unreachable_internal(const char *msg, const char *file,234 unsigned line) {235 // This code intentionally doesn't call the ErrorHandler callback, because236 // llvm_unreachable is intended to be used to indicate "impossible"237 // situations, and not legitimate runtime errors.238 if (msg)239 dbgs() << msg << "\n";240 dbgs() << "UNREACHABLE executed";241 if (file)242 dbgs() << " at " << file << ":" << line;243 dbgs() << "!\n";244 abort();245#ifdef LLVM_BUILTIN_UNREACHABLE246 // Windows systems and possibly others don't declare abort() to be noreturn,247 // so use the unreachable builtin to avoid a Clang self-host warning.248 LLVM_BUILTIN_UNREACHABLE;249#endif250}251 252static void bindingsErrorHandler(void *user_data, const char *reason,253 bool gen_crash_diag) {254 LLVMFatalErrorHandler handler =255 LLVM_EXTENSION reinterpret_cast<LLVMFatalErrorHandler>(user_data);256 handler(reason);257}258 259void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) {260 install_fatal_error_handler(bindingsErrorHandler,261 LLVM_EXTENSION reinterpret_cast<void *>(Handler));262}263 264void LLVMResetFatalErrorHandler() {265 remove_fatal_error_handler();266}267 268#ifdef _WIN32269 270#define WIN32_NO_STATUS271#include "llvm/Support/Windows/WindowsSupport.h"272#undef WIN32_NO_STATUS273#include <ntstatus.h>274#include <winerror.h>275 276// This is equivalent to NtCurrentTeb()->LastStatusValue, but the public277// _TEB definition does not expose the LastStatusValue field directly.278// Avoid offsetting into this structure by calling RtlGetLastNtStatus279// from ntdll.dll.280//281// The return of this function will roughly match that of282// GetLastError, but this lower level API disambiguates some cases283// that GetLastError does not.284//285// For more information, see:286// https://www.geoffchappell.com/studies/windows/km/ntoskrnl/inc/api/pebteb/teb/index.htm287// https://github.com/llvm/llvm-project/issues/89137288extern "C" NTSYSAPI NTSTATUS NTAPI RtlGetLastNtStatus();289 290// This function obtains the last error code and maps it. It may call291// RtlGetLastNtStatus, which is a lower level API that can return a292// more specific error code than GetLastError.293std::error_code llvm::mapLastWindowsError() {294 unsigned EV = ::GetLastError();295 // The mapping of NTSTATUS to Win32 error loses some information; special296 // case the generic ERROR_ACCESS_DENIED code to check the underlying297 // NTSTATUS and potentially return a more accurate error code.298 if (EV == ERROR_ACCESS_DENIED) {299 llvm::errc code = RtlGetLastNtStatus() == STATUS_DELETE_PENDING300 ? errc::delete_pending301 : errc::permission_denied;302 return make_error_code(code);303 }304 return mapWindowsError(EV);305}306 307// I'd rather not double the line count of the following.308#define MAP_ERR_TO_COND(x, y) \309 case x: \310 return make_error_code(errc::y)311 312std::error_code llvm::mapWindowsError(unsigned EV) {313 switch (EV) {314 MAP_ERR_TO_COND(ERROR_ACCESS_DENIED, permission_denied);315 MAP_ERR_TO_COND(ERROR_ALREADY_EXISTS, file_exists);316 MAP_ERR_TO_COND(ERROR_BAD_NETPATH, no_such_file_or_directory);317 MAP_ERR_TO_COND(ERROR_BAD_PATHNAME, no_such_file_or_directory);318 MAP_ERR_TO_COND(ERROR_BAD_UNIT, no_such_device);319 MAP_ERR_TO_COND(ERROR_BROKEN_PIPE, broken_pipe);320 MAP_ERR_TO_COND(ERROR_BUFFER_OVERFLOW, filename_too_long);321 MAP_ERR_TO_COND(ERROR_BUSY, device_or_resource_busy);322 MAP_ERR_TO_COND(ERROR_BUSY_DRIVE, device_or_resource_busy);323 MAP_ERR_TO_COND(ERROR_CANNOT_MAKE, permission_denied);324 MAP_ERR_TO_COND(ERROR_CANTOPEN, io_error);325 MAP_ERR_TO_COND(ERROR_CANTREAD, io_error);326 MAP_ERR_TO_COND(ERROR_CANTWRITE, io_error);327 MAP_ERR_TO_COND(ERROR_CURRENT_DIRECTORY, permission_denied);328 MAP_ERR_TO_COND(ERROR_DEV_NOT_EXIST, no_such_device);329 MAP_ERR_TO_COND(ERROR_DEVICE_IN_USE, device_or_resource_busy);330 MAP_ERR_TO_COND(ERROR_DIR_NOT_EMPTY, directory_not_empty);331 MAP_ERR_TO_COND(ERROR_DIRECTORY, invalid_argument);332 MAP_ERR_TO_COND(ERROR_DISK_FULL, no_space_on_device);333 MAP_ERR_TO_COND(ERROR_FILE_EXISTS, file_exists);334 MAP_ERR_TO_COND(ERROR_FILE_NOT_FOUND, no_such_file_or_directory);335 MAP_ERR_TO_COND(ERROR_HANDLE_DISK_FULL, no_space_on_device);336 MAP_ERR_TO_COND(ERROR_INVALID_ACCESS, permission_denied);337 MAP_ERR_TO_COND(ERROR_INVALID_DRIVE, no_such_device);338 MAP_ERR_TO_COND(ERROR_INVALID_FUNCTION, function_not_supported);339 MAP_ERR_TO_COND(ERROR_INVALID_HANDLE, invalid_argument);340 MAP_ERR_TO_COND(ERROR_INVALID_NAME, invalid_argument);341 MAP_ERR_TO_COND(ERROR_INVALID_PARAMETER, invalid_argument);342 MAP_ERR_TO_COND(ERROR_LOCK_VIOLATION, no_lock_available);343 MAP_ERR_TO_COND(ERROR_LOCKED, no_lock_available);344 MAP_ERR_TO_COND(ERROR_NEGATIVE_SEEK, invalid_argument);345 MAP_ERR_TO_COND(ERROR_NOACCESS, permission_denied);346 MAP_ERR_TO_COND(ERROR_NOT_ENOUGH_MEMORY, not_enough_memory);347 MAP_ERR_TO_COND(ERROR_NOT_READY, resource_unavailable_try_again);348 MAP_ERR_TO_COND(ERROR_NOT_SUPPORTED, not_supported);349 MAP_ERR_TO_COND(ERROR_OPEN_FAILED, io_error);350 MAP_ERR_TO_COND(ERROR_OPEN_FILES, device_or_resource_busy);351 MAP_ERR_TO_COND(ERROR_OUTOFMEMORY, not_enough_memory);352 MAP_ERR_TO_COND(ERROR_PATH_NOT_FOUND, no_such_file_or_directory);353 MAP_ERR_TO_COND(ERROR_READ_FAULT, io_error);354 MAP_ERR_TO_COND(ERROR_REPARSE_TAG_INVALID, invalid_argument);355 MAP_ERR_TO_COND(ERROR_RETRY, resource_unavailable_try_again);356 MAP_ERR_TO_COND(ERROR_SEEK, io_error);357 MAP_ERR_TO_COND(ERROR_SHARING_VIOLATION, permission_denied);358 MAP_ERR_TO_COND(ERROR_TOO_MANY_OPEN_FILES, too_many_files_open);359 MAP_ERR_TO_COND(ERROR_WRITE_FAULT, io_error);360 MAP_ERR_TO_COND(ERROR_WRITE_PROTECT, permission_denied);361 MAP_ERR_TO_COND(WSAEACCES, permission_denied);362 MAP_ERR_TO_COND(WSAEBADF, bad_file_descriptor);363 MAP_ERR_TO_COND(WSAEFAULT, bad_address);364 MAP_ERR_TO_COND(WSAEINTR, interrupted);365 MAP_ERR_TO_COND(WSAEINVAL, invalid_argument);366 MAP_ERR_TO_COND(WSAEMFILE, too_many_files_open);367 MAP_ERR_TO_COND(WSAENAMETOOLONG, filename_too_long);368 default:369 return std::error_code(EV, std::system_category());370 }371}372 373#endif374