Making these thread programs pointy

Author: Babkock

network/http.c

@@ -105,7 +105,9 @@ static void serve_file(FILE *stream, struct stat *stat, char *filename) {
 }
 
 static void serve_directory(int cfd, char *filename) {
-	char buf[BBUFSIZE];
+	//char buf[BBUFSIZE];
+	char *buf;
+	buf = (char *)malloc((sizeof(char) * BBUFSIZE));
 
 	sprintf(buf, "HTTP/1.1 200 OK\r\n%s%s%s%s%s%s%s%s",
 		"Server: My Web Server\r\n",
@@ -124,9 +126,13 @@ static void serve_directory(int cfd, char *filename) {
 	DIR *d;
 
 	if ((fd = open(filename, O_RDONLY, 0)) < 0) {
+		free(buf);
+		buf = NULL;
 		error("Could not open directory\n");
 	}
 	if (write(cfd, buf, strlen(buf)) < 0) {
+		free(buf);
+		buf = NULL;
 		error("Could not write to buffer\n");
 	}
 	d = fdopendir(fd);
@@ -154,6 +160,9 @@ static void serve_directory(int cfd, char *filename) {
 	}
 	sprintf(buf, "</tbody></table></body></html>");
 	write(cfd, buf, strlen(buf));
+	//
+	free(buf);
+	buf = NULL;
 
 	close(fd);
 	closedir(d);

thread/condsignal.c

@@ -14,12 +14,48 @@ int done = 0;
 
 pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
 pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
-void *entry(void *id);
+
+static void *entry(void *id) {
+	const int realId = (long)id;
+	int i;
+
+	for (i = 0; i < 5; i++) {
+		printf("Thread %d: working %d / 5\n", realId, i);
+		sleep(1);
+	}
+
+	/* acquire mutex from main(), then release back to main() after
+	 * condition is signalled */
+	if (pthread_mutex_lock(&lock) != 0) {
+		fprintf(stderr, "Thread %d could not lock mutex, error %d\n", realId, errno);
+		abort();
+	}
+
+	/* thread is finished */
+	done++;
+	printf("Thread %d is done. %d threads done. Signalling...\n", realId, done);
+
+	/* wake the sleeping main thread */
+	if (pthread_cond_signal(&cond) != 0) {
+		fprintf(stderr, "Thread %d could not wake sleeping main, error %d\n", realId, errno);
+		abort();
+	}
+	
+	if (pthread_mutex_unlock(&lock) != 0) {
+		fprintf(stderr, "Thread %d could not unlock mutex, error %d\n", realId, errno);
+		abort();
+	}
+
+	pthread_exit(NULL);
+	return NULL;
+}
 
 int main(void) {
+	int t;
 	printf("Main thread starting\n");
 	pthread_t *threads = (pthread_t *)malloc(sizeof(pthread_t) * THREADS);
-	for (int t = 0; t < THREADS; t++)
+	
+	for (t = 0; t < THREADS; t++)
 		pthread_create(&threads[t], NULL, entry, (void *)(long)t);
 
 	if (pthread_mutex_init(&lock, NULL) != 0) {
@@ -52,41 +88,10 @@ int main(void) {
 		free(threads);
 		return 1;
 	}
+
+	pthread_exit(NULL);
 	pthread_mutex_destroy(&lock);
 	free(threads);
 	return 0;
 }
 
-void *entry(void *id) {
-	const int realId = (long)id;
-
-	for (int i = 0; i < 5; i++) {
-		printf("Thread %d: working %d / 5\n", realId, i);
-		sleep(1);
-	}
-
-	/* acquire mutex from main(), then release back to main() after
-	 * condition is signalled */
-	if (pthread_mutex_lock(&lock) != 0) {
-		fprintf(stderr, "Thread %d could not lock mutex, error %d\n", realId, errno);
-		abort();
-	}
-
-	/* thread is finished */
-	done++;
-	printf("Thread %d is done. %d threads done. Signalling...\n", realId, done);
-
-	/* wake the sleeping main thread */
-	if (pthread_cond_signal(&cond) != 0) {
-		fprintf(stderr, "Thread %d could not wake sleeping main, error %d\n", realId, errno);
-		abort();
-	}
-	
-	if (pthread_mutex_unlock(&lock) != 0) {
-		fprintf(stderr, "Thread %d could not unlock mutex, error %d\n", realId, errno);
-		abort();
-	}
-
-	return NULL;
-}
-

thread/mutex.c

@@ -6,40 +6,52 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#define THREADS 4
 
-pthread_t tid[4];
 int counter;
-pthread_mutex_t lock;
+pthread_mutex_t *lock;
 
-void *handler(void *arg) {
-	pthread_mutex_lock(&lock);
+static void *handler(void *arg) {
+	pthread_mutex_lock(lock);
 	counter++;
+	printf("Arg = %s\n", arg);
 	printf("Job %d has started\n", counter);
 	sleep(2);
 	printf("Job %d has finished\n", counter);
-	pthread_mutex_unlock(&lock);
+	pthread_mutex_unlock(lock);
 	return NULL;
 }
 
 int main(void) {
 	int i, error;
 
-	if (pthread_mutex_init(&lock, NULL) != 0) {
+	pthread_t *tid = (pthread_t *)malloc((sizeof(pthread_t) * THREADS));
+	lock = (pthread_mutex_t *)malloc(sizeof(pthread_mutex_t));
+
+	if (pthread_mutex_init(lock, NULL) != 0) {
 		fprintf(stderr, "Cannot init mutex\n");
 		return 1;
 	}
 
 	for (i = 0; i < 4; i++) {
-		error = pthread_create(&(tid[i]), NULL, &handler, NULL);
+		error = pthread_create(&tid[i], NULL, &handler, "hello");
 		if (error != 0) {
 			fprintf(stderr, "Thread can't be created: [%s]\n", strerror(error));
 		}
 	}
+	if (error != 0) {
+		free(lock);
+		free(tid);
+		return 1;
+	}
+
 	for (i = 0; i < 4; i++) {
 		pthread_join(tid[i], NULL);
 	}
 
-	pthread_mutex_destroy(&lock);
+	pthread_mutex_destroy(lock);
+	free(lock);
+	free(tid);
 
 	return 0;
 }