libusbmuxd: use a monitor to handle device events and use a device list cache

this greatly improves the lookup speed if a lot of devices are attached.

1 files changed, 74 insertions, 24 deletions

diff --git a/libusbmuxd/libusbmuxd.c b/libusbmuxd/libusbmuxd.c
index 956dd90..8470ddc 100644
--- a/libusbmuxd/libusbmuxd.c
+++ b/libusbmuxd/libusbmuxd.c
@@ -68,8 +68,13 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 static int libusbmuxd_debug = 0;
 #define DEBUG(x, y, ...) if (x <= libusbmuxd_debug) fprintf(stderr, (y), __VA_ARGS__);
 
+static int libusbmuxd_initialized = 0;
+
 static struct collection devices;
+static int handle_events = 0;
+
 static usbmuxd_event_cb_t event_cb = NULL;
+static void* event_user_data = NULL;
 #ifdef WIN32
 HANDLE devmon = NULL;
 CRITICAL_SECTION mutex;
@@ -77,7 +82,7 @@ static int mutex_initialized = 0;
 #define LOCK if (!mutex_initialized) { InitializeCriticalSection(&mutex); mutex_initialized = 1; } EnterCriticalSection(&mutex);
 #define UNLOCK LeaveCriticalSection(&mutex);
 #else
-pthread_t devmon;
+pthread_t devmon = 0;
 pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
 #define LOCK pthread_mutex_lock(&mutex)
 #define UNLOCK pthread_mutex_unlock(&mutex)	
@@ -619,15 +624,15 @@ static void *device_monitor(void *data)
 #ifndef WIN32
 	pthread_cleanup_push(device_monitor_cleanup, NULL);
 #endif
-	while (event_cb) {
+	while (handle_events) {
 
 		listenfd = usbmuxd_listen();
 		if (listenfd < 0) {
 			continue;
 		}
 
-		while (event_cb) {
-			int res = get_next_event(listenfd, event_cb, data);
+		while (handle_events) {
+			int res = get_next_event(listenfd, event_cb, event_user_data);
 			if (res < 0) {
 			    break;
 			}
@@ -642,34 +647,32 @@ static void *device_monitor(void *data)
 	return NULL;
 }
 
-int usbmuxd_subscribe(usbmuxd_event_cb_t callback, void *user_data)
+int usbmuxd_init()
 {
-	int res;
-
-	if (!callback) {
-		return -EINVAL;
-	}
-	event_cb = callback;
-
+	int res = 0;
+	handle_events = 1;
 #ifdef WIN32
-	res = 0;
-	devmon = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)device_monitor, user_data, 0, NULL);
+	devmon = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)device_monitor, NULL, 0, NULL);
 	if (devmon == NULL) {
 		res = GetLastError();
 	}
 #else
-	res = pthread_create(&devmon, NULL, device_monitor, user_data);
+	res = pthread_create(&devmon, NULL, device_monitor, NULL);
 #endif
 	if (res != 0) {
 		DEBUG(1, "%s: ERROR: Could not start device watcher thread!\n", __func__);
+		handle_events = 0;
 		return res;
 	}
+	struct timespec ts = {0, 250000000};
+	nanosleep(&ts, NULL);
+	libusbmuxd_initialized = 1;
 	return 0;
 }
 
-int usbmuxd_unsubscribe()
+int usbmuxd_deinit()
 {
-	event_cb = NULL;
+	handle_events = 0;
 
 	shutdown_socket(listenfd, SHUT_RDWR);
 
@@ -683,6 +686,33 @@ int usbmuxd_unsubscribe()
 		pthread_join(devmon, NULL);
 	}
 #endif
+	libusbmuxd_initialized = 0;
+	return 0;
+}
+
+int usbmuxd_subscribe(usbmuxd_event_cb_t callback, void *user_data)
+{
+	if (!callback) {
+		return -EINVAL;
+	}
+	event_cb = callback;
+	event_user_data = user_data;
+
+	if (!libusbmuxd_initialized) {
+		usbmuxd_init();
+	} else {
+		FOREACH(usbmuxd_device_info_t *dev, &devices) {
+			generate_event(callback, dev, UE_DEVICE_ADD, user_data);
+		} ENDFOREACH
+	}
+
+	return 0;
+}
+
+int usbmuxd_unsubscribe()
+{
+	event_cb = NULL;
+	event_user_data = NULL;
 
 	return 0;
 }
@@ -711,14 +741,14 @@ retry:
 	}
 
 	use_tag++;
-	LOCK;
+	//LOCK;
 	if (send_listen_packet(sfd, use_tag) > 0) {
 		res = -1;
 		// get response
 		if (usbmuxd_get_result(sfd, use_tag, &res) && (res == 0)) {
 			listen_success = 1;
 		} else {
-			UNLOCK;
+			//UNLOCK;
 			close_socket(sfd);
 #ifdef HAVE_PLIST
 			if ((res == RESULT_BADVERSION) && (proto_version != 1)) {
@@ -732,7 +762,7 @@ retry:
 	}
 
 	if (!listen_success) {
-		UNLOCK;
+		//UNLOCK;
 		DEBUG(1, "%s: Could not send listen request!\n", __func__);
 		return -1;
 	}
@@ -741,12 +771,12 @@ retry:
 
 	// receive device list
 	while (1) {
-		if (receive_packet(sfd, &hdr, &payload, 1000) > 0) {
+		if (receive_packet(sfd, &hdr, &payload, 250) > 0) {
 			if (hdr.message == MESSAGE_DEVICE_ADD) {
 				dev = payload;
 				usbmuxd_device_info_t *devinfo = (usbmuxd_device_info_t*)malloc(sizeof(usbmuxd_device_info_t));
 				if (!devinfo) {
-					UNLOCK;
+					//UNLOCK;
 					DEBUG(1, "%s: Out of memory!\n", __func__);
 					free(payload);
 					return -1;
@@ -790,7 +820,7 @@ retry:
 			break;
 		}
 	}
-	UNLOCK;
+	//UNLOCK;
 
 	// explicitly close connection
 	close_socket(sfd);
@@ -824,16 +854,34 @@ int usbmuxd_device_list_free(usbmuxd_device_info_t **device_list)
 int usbmuxd_get_device_by_udid(const char *udid, usbmuxd_device_info_t *device)
 {
 	usbmuxd_device_info_t *dev_list = NULL;
+	int result = 0;
 
 	if (!device) {
 		return -EINVAL;
 	}
+
+	if (!libusbmuxd_initialized) {
+		usbmuxd_init();
+	}
+
+	if (udid && devmon && (pthread_kill(devmon, 0) == 0)) {
+		result = -ENODEV;
+		FOREACH(usbmuxd_device_info_t *dev, &devices) {
+		if (dev && dev->udid && (strcmp(dev->udid, udid) == 0)) {
+			device->handle = dev->handle;
+			device->product_id = dev->product_id;
+			strcpy(device->udid, dev->udid);
+			result = 1;
+			break;
+		}
+		} ENDFOREACH
+		return result;
+	} else {
 	if (usbmuxd_get_device_list(&dev_list) < 0) {
 		return -ENODEV;
 	}
 
 	int i;
-	int result = 0;
 	for (i = 0; dev_list[i].handle > 0; i++) {
 	 	if (!udid) {
 			device->handle = dev_list[i].handle;
@@ -853,6 +901,8 @@ int usbmuxd_get_device_by_udid(const char *udid, usbmuxd_device_info_t *device)
 
 	free(dev_list);
 
+	}
+
 	return result;
 }