X-Git-Url: https://git.sesse.net/?p=cubemap;a=blobdiff_plain;f=thread.cpp;h=2aaf34f11441cefe3befcba7b33cc08c6d4f6db6;hp=7aded3bb8cda25790550a3818a4b3a40ff205496;hb=562cf44b96b5c0260d1a1ab18b2dd2408b6d1fc8;hpb=94561762b1294b76508eb5554aedbb56fcaececc

diff --git a/thread.cpp b/thread.cpp
index 7aded3b..2aaf34f 100644
--- a/thread.cpp
+++ b/thread.cpp
@@ -1,23 +1,33 @@
+#include <assert.h>
+#include <errno.h>
+#include <poll.h>
+#include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <signal.h>
+#include <unistd.h>
 
+#include "log.h"
+#include "mutexlock.h"
 #include "thread.h"
-	
+
 Thread::~Thread() {}
 
 void Thread::run()
 {
-	should_stop = false;
+	pthread_mutex_init(&should_stop_mutex, NULL);
+	should_stop_status = false;
 	pthread_create(&worker_thread, NULL, &Thread::do_work_thunk, this);
 }
 
 void Thread::stop()
 {
-	should_stop = true;
-	pthread_kill(worker_thread, SIGHUP);
+	{
+		MutexLock lock(&should_stop_mutex);
+		should_stop_status = true;
+	}
+	wakeup();
 	if (pthread_join(worker_thread, NULL) == -1) {
-		perror("pthread_join");
+		log_perror("pthread_join");
 		exit(1);
 	}
 }
@@ -25,7 +35,62 @@ void Thread::stop()
 void *Thread::do_work_thunk(void *arg)
 {
 	Thread *thread = reinterpret_cast<Thread *>(arg);
+
+	// Block SIGHUP; only the main thread should see that.
+	// (This isn't strictly required, but it makes it easier to debug that indeed
+	// SIGUSR1 was what woke us up.)
+	sigset_t set;
+	sigaddset(&set, SIGHUP);
+	int err = pthread_sigmask(SIG_BLOCK, &set, NULL);
+	if (err != 0) {
+		errno = err;
+		log_perror("pthread_sigmask");
+		exit(1);
+	}
+
+	// Block SIGUSR1, and store the old signal mask.
+	sigemptyset(&set);
+	sigaddset(&set, SIGUSR1);
+	err = pthread_sigmask(SIG_BLOCK, &set, &thread->sigset_without_usr1_block);
+	if (err != 0) {
+		errno = err;
+		log_perror("pthread_sigmask");
+		exit(1);
+	}
+
+	// Call the right thunk.
 	thread->do_work();
 	return NULL;
 }
 
+bool Thread::wait_for_activity(int fd, short events, const struct timespec *timeout_ts)
+{
+	pollfd pfd;
+	pfd.fd = fd;
+	pfd.events = events;
+
+	for ( ;; ) {
+		int nfds = ppoll(&pfd, (fd == -1) ? 0 : 1, timeout_ts, &sigset_without_usr1_block);
+		if (nfds == -1 && errno == EINTR) {
+			return false;
+		}
+		if (nfds == -1) {
+			log_perror("poll");
+			usleep(100000);
+			continue;
+		}
+		assert(nfds <= 1);
+		return (nfds == 1);
+	}
+}
+
+void Thread::wakeup()
+{
+	pthread_kill(worker_thread, SIGUSR1);
+}
+
+bool Thread::should_stop()
+{
+	MutexLock lock(&should_stop_mutex);
+	return should_stop_status;
+}