catch2/include/internal/catch_fatal_condition.cpp
2022-12-12 08:09:47 -08:00

244 lines
8.8 KiB
C++

/*
* Created by Phil on 21/08/2014
* Copyright 2014 Two Blue Cubes Ltd. All rights reserved.
*
* Distributed under the Boost Software License, Version 1.0. (See accompanying
* file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
*
*/
/** \file
* This file provides platform specific implementations of FatalConditionHandler
*
* This means that there is a lot of conditional compilation, and platform
* specific code. Currently, Catch2 supports a dummy handler (if no
* handler is desired), and 2 platform specific handlers:
* * Windows' SEH
* * POSIX signals
*
* Consequently, various pieces of code below are compiled if either of
* the platform specific handlers is enabled, or if none of them are
* enabled. It is assumed that both cannot be enabled at the same time,
* and doing so should cause a compilation error.
*
* If another platform specific handler is added, the compile guards
* below will need to be updated taking these assumptions into account.
*/
#include "catch_fatal_condition.h"
#include "catch_context.h"
#include "catch_enforce.h"
#include "catch_run_context.h"
#include "catch_windows_h_proxy.h"
#include <algorithm>
#if !defined( CATCH_CONFIG_WINDOWS_SEH ) && !defined( CATCH_CONFIG_POSIX_SIGNALS )
namespace Catch {
// If neither SEH nor signal handling is required, the handler impls
// do not have to do anything, and can be empty.
void FatalConditionHandler::engage_platform() {}
void FatalConditionHandler::disengage_platform() {}
FatalConditionHandler::FatalConditionHandler() = default;
FatalConditionHandler::~FatalConditionHandler() = default;
} // end namespace Catch
#endif // !CATCH_CONFIG_WINDOWS_SEH && !CATCH_CONFIG_POSIX_SIGNALS
#if defined( CATCH_CONFIG_WINDOWS_SEH ) && defined( CATCH_CONFIG_POSIX_SIGNALS )
#error "Inconsistent configuration: Windows' SEH handling and POSIX signals cannot be enabled at the same time"
#endif // CATCH_CONFIG_WINDOWS_SEH && CATCH_CONFIG_POSIX_SIGNALS
#if defined( CATCH_CONFIG_WINDOWS_SEH ) || defined( CATCH_CONFIG_POSIX_SIGNALS )
namespace {
//! Signals fatal error message to the run context
void reportFatal( char const * const message ) {
Catch::getCurrentContext().getResultCapture()->handleFatalErrorCondition( message );
}
//! Minimal size Catch2 needs for its own fatal error handling.
//! Picked anecdotally, so it might not be sufficient on all
//! platforms, and for all configurations.
constexpr std::size_t minStackSizeForErrors = 32 * 1024;
} // end unnamed namespace
#endif // CATCH_CONFIG_WINDOWS_SEH || CATCH_CONFIG_POSIX_SIGNALS
#if defined( CATCH_CONFIG_WINDOWS_SEH )
namespace Catch {
struct SignalDefs { DWORD id; const char* name; };
// There is no 1-1 mapping between signals and windows exceptions.
// Windows can easily distinguish between SO and SigSegV,
// but SigInt, SigTerm, etc are handled differently.
static SignalDefs signalDefs[] = {
{ static_cast<DWORD>(EXCEPTION_ILLEGAL_INSTRUCTION), "SIGILL - Illegal instruction signal" },
{ static_cast<DWORD>(EXCEPTION_STACK_OVERFLOW), "SIGSEGV - Stack overflow" },
{ static_cast<DWORD>(EXCEPTION_ACCESS_VIOLATION), "SIGSEGV - Segmentation violation signal" },
{ static_cast<DWORD>(EXCEPTION_INT_DIVIDE_BY_ZERO), "Divide by zero error" },
};
static LONG CALLBACK topLevelExceptionFilter(PEXCEPTION_POINTERS ExceptionInfo) {
for (auto const& def : signalDefs) {
if (ExceptionInfo->ExceptionRecord->ExceptionCode == def.id) {
reportFatal(def.name);
}
}
// If its not an exception we care about, pass it along.
// This stops us from eating debugger breaks etc.
return EXCEPTION_CONTINUE_SEARCH;
}
// Since we do not support multiple instantiations, we put these
// into global variables and rely on cleaning them up in outlined
// constructors/destructors
static LPTOP_LEVEL_EXCEPTION_FILTER previousTopLevelExceptionFilter = nullptr;
// For MSVC, we reserve part of the stack memory for handling
// memory overflow structured exception.
FatalConditionHandler::FatalConditionHandler() {
ULONG guaranteeSize = static_cast<ULONG>(minStackSizeForErrors);
if (!SetThreadStackGuarantee(&guaranteeSize)) {
// We do not want to fully error out, because needing
// the stack reserve should be rare enough anyway.
Catch::cerr()
<< "Failed to reserve piece of stack."
<< " Stack overflows will not be reported successfully.";
}
}
// We do not attempt to unset the stack guarantee, because
// Windows does not support lowering the stack size guarantee.
FatalConditionHandler::~FatalConditionHandler() = default;
void FatalConditionHandler::engage_platform() {
// Register as a the top level exception filter.
previousTopLevelExceptionFilter = SetUnhandledExceptionFilter(topLevelExceptionFilter);
}
void FatalConditionHandler::disengage_platform() noexcept {
if (SetUnhandledExceptionFilter(previousTopLevelExceptionFilter) != topLevelExceptionFilter) {
Catch::cerr()
<< "Unexpected SEH unhandled exception filter on disengage."
<< " The filter was restored, but might be rolled back unexpectedly.";
}
previousTopLevelExceptionFilter = nullptr;
}
} // end namespace Catch
#endif // CATCH_CONFIG_WINDOWS_SEH
#if defined( CATCH_CONFIG_POSIX_SIGNALS )
#include <signal.h>
namespace Catch {
struct SignalDefs {
int id;
const char* name;
};
static SignalDefs signalDefs[] = {
{ SIGINT, "SIGINT - Terminal interrupt signal" },
{ SIGILL, "SIGILL - Illegal instruction signal" },
{ SIGFPE, "SIGFPE - Floating point error signal" },
{ SIGSEGV, "SIGSEGV - Segmentation violation signal" },
{ SIGTERM, "SIGTERM - Termination request signal" },
{ SIGABRT, "SIGABRT - Abort (abnormal termination) signal" }
};
// Older GCCs trigger -Wmissing-field-initializers for T foo = {}
// which is zero initialization, but not explicit. We want to avoid
// that.
#if defined(__GNUC__)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wmissing-field-initializers"
#endif
static char* altStackMem = nullptr;
static std::size_t altStackSize = 0;
static stack_t oldSigStack{};
static struct sigaction oldSigActions[sizeof(signalDefs) / sizeof(SignalDefs)]{};
static void restorePreviousSignalHandlers() {
// We set signal handlers back to the previous ones. Hopefully
// nobody overwrote them in the meantime, and doesn't expect
// their signal handlers to live past ours given that they
// installed them after ours..
for (std::size_t i = 0; i < sizeof(signalDefs) / sizeof(SignalDefs); ++i) {
sigaction(signalDefs[i].id, &oldSigActions[i], nullptr);
}
// Return the old stack
sigaltstack(&oldSigStack, nullptr);
}
static void handleSignal( int sig ) {
char const * name = "<unknown signal>";
for (auto const& def : signalDefs) {
if (sig == def.id) {
name = def.name;
break;
}
}
// We need to restore previous signal handlers and let them do
// their thing, so that the users can have the debugger break
// when a signal is raised, and so on.
restorePreviousSignalHandlers();
reportFatal( name );
raise( sig );
}
FatalConditionHandler::FatalConditionHandler() {
assert(!altStackMem && "Cannot initialize POSIX signal handler when one already exists");
if (altStackSize == 0) {
altStackSize = std::max(static_cast<size_t>(SIGSTKSZ), minStackSizeForErrors);
}
altStackMem = new char[altStackSize]();
}
FatalConditionHandler::~FatalConditionHandler() {
delete[] altStackMem;
// We signal that another instance can be constructed by zeroing
// out the pointer.
altStackMem = nullptr;
}
void FatalConditionHandler::engage_platform() {
stack_t sigStack;
sigStack.ss_sp = altStackMem;
sigStack.ss_size = altStackSize;
sigStack.ss_flags = 0;
sigaltstack(&sigStack, &oldSigStack);
struct sigaction sa = { };
sa.sa_handler = handleSignal;
sa.sa_flags = SA_ONSTACK;
for (std::size_t i = 0; i < sizeof(signalDefs)/sizeof(SignalDefs); ++i) {
sigaction(signalDefs[i].id, &sa, &oldSigActions[i]);
}
}
#if defined(__GNUC__)
# pragma GCC diagnostic pop
#endif
void FatalConditionHandler::disengage_platform() {
restorePreviousSignalHandlers();
}
} // end namespace Catch
#endif // CATCH_CONFIG_POSIX_SIGNALS