Remove signalThread and move reaping to catchSignals

This commit is contained in:
literallyvoid
2025-04-12 16:41:18 -07:00
parent b03ecb3d74
commit 97591c825a

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@ -14,64 +14,6 @@ std::mutex reap_mtx;
std::list<pid_t> reap;
volatile bool reload;
void* signalThread(void* args) {
int err;
int signum;
sigset_t mask;
sigemptyset(&mask);
sigaddset(&mask, SIGCHLD);
while (true) {
err = sigwait(&mask, &signum);
if (err != 0) {
spdlog::error("sigwait failed: {}", strerror(errno));
continue;
}
switch (signum) {
case SIGCHLD:
spdlog::debug("Received SIGCHLD in signalThread");
if (!reap.empty()) {
reap_mtx.lock();
for (auto it = reap.begin(); it != reap.end(); ++it) {
if (waitpid(*it, nullptr, WNOHANG) == *it) {
spdlog::debug("Reaped child with PID: {}", *it);
it = reap.erase(it);
}
}
reap_mtx.unlock();
}
break;
default:
spdlog::debug("Received signal with number {}, but not handling", signum);
break;
}
}
}
void startSignalThread() {
int err;
sigset_t mask;
sigemptyset(&mask);
sigaddset(&mask, SIGCHLD);
// Block SIGCHLD so it can be handled by the signal thread
// Any threads created by this one (the main thread) should not
// modify their signal mask to unblock SIGCHLD
err = pthread_sigmask(SIG_BLOCK, &mask, nullptr);
if (err != 0) {
spdlog::error("pthread_sigmask failed in startSignalThread: {}", strerror(err));
exit(1);
}
pthread_t thread_id;
err = pthread_create(&thread_id, nullptr, signalThread, nullptr);
if (err != 0) {
spdlog::error("pthread_create failed in startSignalThread: {}", strerror(err));
exit(1);
}
}
static int signal_pipe_write_fd;
// Write a single signal to `signal_pipe_write_fd`.
@ -87,8 +29,8 @@ static void writeSignalToPipe(int signum) {
// This initializes `signal_pipe_write_fd`, and sets up signal handlers.
//
// This function will run forever, emitting every `SIGUSR1`, `SIGUSR2`,
// `SIGINT`, and `SIGRTMIN + 1`...`SIGRTMAX` signal received to
// `signal_handler`.
// `SIGINT`, `SIGCHLD`, and `SIGRTMIN + 1`...`SIGRTMAX` signal received
// to `signal_handler`.
static void catchSignals(waybar::SafeSignal<int> &signal_handler) {
int fd[2];
pipe(fd);
@ -108,6 +50,7 @@ static void catchSignals(waybar::SafeSignal<int> &signal_handler) {
std::signal(SIGUSR1, writeSignalToPipe);
std::signal(SIGUSR2, writeSignalToPipe);
std::signal(SIGINT, writeSignalToPipe);
std::signal(SIGCHLD, writeSignalToPipe);
for (int sig = SIGRTMIN + 1; sig <= SIGRTMAX; ++sig) {
std::signal(sig, writeSignalToPipe);
@ -156,6 +99,19 @@ static void handleSignalMainThread(int signum) {
reload = false;
waybar::Client::inst()->reset();
break;
case SIGCHLD:
spdlog::debug("Received SIGCHLD in signalThread");
if (!reap.empty()) {
reap_mtx.lock();
for (auto it = reap.begin(); it != reap.end(); ++it) {
if (waitpid(*it, nullptr, WNOHANG) == *it) {
spdlog::debug("Reaped child with PID: {}", *it);
it = reap.erase(it);
}
}
reap_mtx.unlock();
}
break;
default:
spdlog::debug("Received signal with number {}, but not handling", signum);
break;
@ -166,8 +122,6 @@ int main(int argc, char* argv[]) {
try {
auto* client = waybar::Client::inst();
startSignalThread();
waybar::SafeSignal<int> posix_signal_received;
posix_signal_received.connect([&](int signum) {
handleSignalMainThread(signum);