static void uninstallSignalHandler(void)
{
KSLOG_DEBUG("Uninstalling signal handlers.");
const int* fatalSignals = kssignal_fatalSignals();
int fatalSignalsCount = kssignal_numFatalSignals();
for(int i = 0; i < fatalSignalsCount; i++)
{
KSLOG_DEBUG("Restoring original handler for signal %d", fatalSignals[i]);
sigaction(fatalSignals[i], &g_previousSignalHandlers[i], NULL);
}
KSLOG_DEBUG("Signal handlers uninstalled.");
}
void kscrashsentry_uninstallSignalHandler(void)
{
KSLOG_DEBUG("Uninstalling signal handlers.");
if(!g_installed)
{
KSLOG_DEBUG("Signal handlers were already uninstalled.");
return;
}
const int* fatalSignals = kssignal_fatalSignals();
int fatalSignalsCount = kssignal_numFatalSignals();
for(int i = 0; i < fatalSignalsCount; i++)
{
KSLOG_DEBUG("Restoring original handler for signal %d", fatalSignals[i]);
sigaction(fatalSignals[i], &g_previousSignalHandlers[i], NULL);
}
KSLOG_DEBUG("Signal handlers uninstalled.");
g_installed = 0;
}
bool kscrashsentry_installSignalHandler(KSCrash_SentryContext* context)
{
KSLOG_DEBUG("Installing signal handler.");
if(g_installed)
{
KSLOG_DEBUG("Signal handler already installed.");
return true;
}
g_installed = 1;
g_context = context;
if(g_signalStack.ss_size == 0)
{
KSLOG_DEBUG("Allocating signal stack area.");
g_signalStack.ss_size = SIGSTKSZ;
g_signalStack.ss_sp = malloc(g_signalStack.ss_size);
}
KSLOG_DEBUG("Setting signal stack area.");
if(sigaltstack(&g_signalStack, NULL) != 0)
{
KSLOG_ERROR("signalstack: %s", strerror(errno));
goto failed;
}
const int* fatalSignals = kssignal_fatalSignals();
int fatalSignalsCount = kssignal_numFatalSignals();
if(g_previousSignalHandlers == NULL)
{
KSLOG_DEBUG("Allocating memory to store previous signal handlers.");
g_previousSignalHandlers = malloc(sizeof(*g_previousSignalHandlers)
* (unsigned)fatalSignalsCount);
}
struct sigaction action = {{0}};
action.sa_flags = SA_SIGINFO | SA_ONSTACK;
#ifdef __LP64__
action.sa_flags |= SA_64REGSET;
#endif
sigemptyset(&action.sa_mask);
action.sa_sigaction = &kssighndl_i_handleSignal;
for(int i = 0; i < fatalSignalsCount; i++)
{
KSLOG_DEBUG("Assigning handler for signal %d", fatalSignals[i]);
if(sigaction(fatalSignals[i], &action, &g_previousSignalHandlers[i]) != 0)
{
char sigNameBuff[30];
const char* sigName = kssignal_signalName(fatalSignals[i]);
if(sigName == NULL)
{
snprintf(sigNameBuff, sizeof(sigNameBuff), "%d", fatalSignals[i]);
sigName = sigNameBuff;
}
KSLOG_ERROR("sigaction (%s): %s", sigName, strerror(errno));
// Try to reverse the damage
for(i--;i >= 0; i--)
{
sigaction(fatalSignals[i], &g_previousSignalHandlers[i], NULL);
}
goto failed;
}
}
KSLOG_DEBUG("Signal handlers installed.");
return true;
failed:
KSLOG_DEBUG("Failed to install signal handlers.");
g_installed = 0;
return false;
}