X-Git-Url: https://git.sesse.net/?p=cubemap;a=blobdiff_plain;f=thread.cpp;h=2aaf34f11441cefe3befcba7b33cc08c6d4f6db6;hp=f719eacb95c5379a2d664f23c49c04e0b50b767b;hb=562cf44b96b5c0260d1a1ab18b2dd2408b6d1fc8;hpb=4856c49f1b63753ce86ad759ee649a1117628a8e

diff --git a/thread.cpp b/thread.cpp
index f719eac..2aaf34f 100644
--- a/thread.cpp
+++ b/thread.cpp
@@ -1,71 +1,96 @@
+#include <assert.h>
+#include <errno.h>
+#include <poll.h>
+#include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <errno.h>
 
 #include "log.h"
+#include "mutexlock.h"
 #include "thread.h"
-	
+
 Thread::~Thread() {}
 
 void Thread::run()
 {
-	should_stop = false;
-	int pipefd[2];
-	if (pipe2(pipefd, O_CLOEXEC) == -1) {
-		log_perror("pipe");
-		exit(1);
-	}
-	stop_fd_read = pipefd[0];
-	stop_fd_write = pipefd[1];
+	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;
-	char ch = 0;
-	int err;
-	do {
-		err = write(stop_fd_write, &ch, 1);
-	} while (err == -1 && errno == EINTR);
-
-	if (err == -1) {
-		log_perror("write");
+	{
+		MutexLock lock(&should_stop_mutex);
+		should_stop_status = true;
+	}
+	wakeup();
+	if (pthread_join(worker_thread, NULL) == -1) {
+		log_perror("pthread_join");
 		exit(1);
 	}
+}
 
-	do {
-		err = close(stop_fd_write);
-	} while (err == -1 && errno == EINTR);
+void *Thread::do_work_thunk(void *arg)
+{
+	Thread *thread = reinterpret_cast<Thread *>(arg);
 
-	if (err == -1) {
-		log_perror("close");
-		// Can continue (we have close-on-exec).
+	// 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);
 	}
 
-	pthread_kill(worker_thread, SIGHUP);
-	if (pthread_join(worker_thread, NULL) == -1) {
-		log_perror("pthread_join");
+	// 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);
 	}
-	
-	do {
-		err = close(stop_fd_read);
-	} while (err == -1 && errno == EINTR);
 
-	if (err == -1) {
-		log_perror("close");
-		// Can continue (we have close-on-exec).
+	// 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::do_work_thunk(void *arg)
+void Thread::wakeup()
 {
-	Thread *thread = reinterpret_cast<Thread *>(arg);
-	thread->do_work();
-	return NULL;
+	pthread_kill(worker_thread, SIGUSR1);
 }
 
+bool Thread::should_stop()
+{
+	MutexLock lock(&should_stop_mutex);
+	return should_stop_status;
+}