llvm-6502/lib/Support/ErrorHandling.cpp
Zachary Turner 89e90b25e3 Make the error-handling functions thread-safe.
Prior to this change, error handling functions must be installed
and removed only inside of an llvm_[start/stop]_multithreading
pair.  This change allows error handling functions to be installed
any time, and from any thread.

Reviewed by: chandlerc

Differential Revision: http://reviews.llvm.org/D4140

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210937 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-13 21:20:44 +00:00

137 lines
4.5 KiB
C++

//===- lib/Support/ErrorHandling.cpp - Callbacks for errors ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines an API used to indicate fatal error conditions. Non-fatal
// errors (most of them) should be handled through LLVMContext.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/ErrorHandling.h"
#include "llvm-c/Core.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Config/config.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Signals.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/MutexGuard.h"
#include "llvm/Support/Threading.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
#include <cstdlib>
#if defined(HAVE_UNISTD_H)
# include <unistd.h>
#endif
#if defined(_MSC_VER)
# include <io.h>
# include <fcntl.h>
#endif
using namespace llvm;
static fatal_error_handler_t ErrorHandler = nullptr;
static void *ErrorHandlerUserData = nullptr;
static sys::Mutex ErrorHandlerMutex;
void llvm::install_fatal_error_handler(fatal_error_handler_t handler,
void *user_data) {
llvm::MutexGuard Lock(ErrorHandlerMutex);
assert(!ErrorHandler && "Error handler already registered!\n");
ErrorHandler = handler;
ErrorHandlerUserData = user_data;
}
void llvm::remove_fatal_error_handler() {
llvm::MutexGuard Lock(ErrorHandlerMutex);
ErrorHandler = nullptr;
ErrorHandlerUserData = nullptr;
}
void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) {
report_fatal_error(Twine(Reason), GenCrashDiag);
}
void llvm::report_fatal_error(const std::string &Reason, bool GenCrashDiag) {
report_fatal_error(Twine(Reason), GenCrashDiag);
}
void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) {
report_fatal_error(Twine(Reason), GenCrashDiag);
}
void llvm::report_fatal_error(const Twine &Reason, bool GenCrashDiag) {
llvm::fatal_error_handler_t handler = nullptr;
void* handlerData = nullptr;
{
// Only acquire the mutex while reading the handler, so as not to invoke a
// user-supplied callback under a lock.
llvm::MutexGuard Lock(ErrorHandlerMutex);
handler = ErrorHandler;
handlerData = ErrorHandlerUserData;
}
if (handler) {
handler(handlerData, Reason.str(), GenCrashDiag);
} else {
// Blast the result out to stderr. We don't try hard to make sure this
// succeeds (e.g. handling EINTR) and we can't use errs() here because
// raw ostreams can call report_fatal_error.
SmallVector<char, 64> Buffer;
raw_svector_ostream OS(Buffer);
OS << "LLVM ERROR: " << Reason << "\n";
StringRef MessageStr = OS.str();
ssize_t written = ::write(2, MessageStr.data(), MessageStr.size());
(void)written; // If something went wrong, we deliberately just give up.
}
// If we reached here, we are failing ungracefully. Run the interrupt handlers
// to make sure any special cleanups get done, in particular that we remove
// files registered with RemoveFileOnSignal.
sys::RunInterruptHandlers();
exit(1);
}
void llvm::llvm_unreachable_internal(const char *msg, const char *file,
unsigned line) {
// This code intentionally doesn't call the ErrorHandler callback, because
// llvm_unreachable is intended to be used to indicate "impossible"
// situations, and not legitimate runtime errors.
if (msg)
dbgs() << msg << "\n";
dbgs() << "UNREACHABLE executed";
if (file)
dbgs() << " at " << file << ":" << line;
dbgs() << "!\n";
abort();
#ifdef LLVM_BUILTIN_UNREACHABLE
// Windows systems and possibly others don't declare abort() to be noreturn,
// so use the unreachable builtin to avoid a Clang self-host warning.
LLVM_BUILTIN_UNREACHABLE;
#endif
}
static void bindingsErrorHandler(void *user_data, const std::string& reason,
bool gen_crash_diag) {
LLVMFatalErrorHandler handler =
LLVM_EXTENSION reinterpret_cast<LLVMFatalErrorHandler>(user_data);
handler(reason.c_str());
}
void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) {
install_fatal_error_handler(bindingsErrorHandler,
LLVM_EXTENSION reinterpret_cast<void *>(Handler));
}
void LLVMResetFatalErrorHandler() {
remove_fatal_error_handler();
}