llvm/lib/Support/ErrorHandling.cpp
Filip Pizlo 0739140b05 Expose install_fatal_error_handler() through the C API.
I expose the API with some caveats:

- The C++ API involves a traditional void* opaque pointer for the fatal 
error callback.  The C API doesn’t do this.  I don’t think that the void* 
opaque pointer makes any sense since this is a global callback - there will 
only be one of them.  So if you need to pass some data to your callback, 
just put it in a global variable.

- The bindings will ignore the gen_crash_diag boolean.  I ignore it because 
(1) I don’t know what it does, (2) it’s not documented AFAIK, and (3) I 
couldn’t imagine any use for it.  I made the gut call that it probably 
wasn’t important enough to expose through the C API.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192864 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-17 01:38:28 +00:00

122 lines
4.0 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/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/Threading.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm-c/Core.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 = 0;
static void *ErrorHandlerUserData = 0;
void llvm::install_fatal_error_handler(fatal_error_handler_t handler,
void *user_data) {
assert(!llvm_is_multithreaded() &&
"Cannot register error handlers after starting multithreaded mode!\n");
assert(!ErrorHandler && "Error handler already registered!\n");
ErrorHandler = handler;
ErrorHandlerUserData = user_data;
}
void llvm::remove_fatal_error_handler() {
ErrorHandler = 0;
}
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) {
if (ErrorHandler) {
ErrorHandler(ErrorHandlerUserData, 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 =
reinterpret_cast<LLVMFatalErrorHandler>(user_data);
handler(reason.c_str());
}
void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) {
install_fatal_error_handler(
bindingsErrorHandler, reinterpret_cast<void*>(Handler));
}
void LLVMResetFatalErrorHandler() {
remove_fatal_error_handler();
}