preflight: replace idevice_event_* with thread safe implementation

idevice_event_subscribe() calls usbmuxd_subscribe() which will
start a thread waiting for device add/remove events. But this
implementation is not able to handle more than one "subscription".
However the preflight worker will start a thread for _each_ device
resulting in a really messed up situation if more than one device
is attached at the same time. This fix will use usbmuxd's internal
device_remove function calling a preflight callback to make this
implementation thread safe.

4 files changed, 31 insertions, 12 deletions

diff --git a/src/device.c b/src/device.c
index b6cc32a..1e3cc83 100644
--- a/src/device.c
+++ b/src/device.c
@@ -112,6 +112,7 @@ struct mux_device
 	uint16_t next_sport;
 	unsigned char *pktbuf;
 	uint32_t pktlen;
+	void *preflight_cb_data;
 };
 
 static struct collection device_list;
@@ -648,6 +649,7 @@ int device_add(struct usb_device *usbdev)
 	dev->next_sport = 1;
 	dev->pktbuf = malloc(DEV_MRU);
 	dev->pktlen = 0;
+	dev->preflight_cb_data = NULL;
 	struct version_header vh;
 	vh.major = htonl(1);
 	vh.minor = htonl(0);
@@ -674,6 +676,9 @@ void device_remove(struct usb_device *usbdev)
 				client_device_remove(dev->id);
 				collection_free(&dev->connections);
 			}
+			if (dev->preflight_cb_data) {
+				preflight_device_remove_cb(dev->preflight_cb_data);
+			}
 			collection_remove(&device_list, dev);
 			free(dev->pktbuf);
 			free(dev);
@@ -690,7 +695,17 @@ void device_set_visible(int device_id)
 			dev->visible = 1;
 			break;
 		}
-	} ENDFOREACH	
+	} ENDFOREACH
+}
+
+void device_set_preflight_cb_data(int device_id, void* data)
+{
+	FOREACH(struct mux_device *dev, &device_list) {
+		if(dev->id == device_id) {
+			dev->preflight_cb_data = data;
+			break;
+		}
+	} ENDFOREACH
 }
 
 int device_get_count(int include_hidden)
diff --git a/src/device.h b/src/device.h
index d7c82ca..95d470e 100644
--- a/src/device.h
+++ b/src/device.h
@@ -41,6 +41,7 @@ void device_client_process(int device_id, struct mux_client *client, short event
 void device_abort_connect(int device_id, struct mux_client *client);
 
 void device_set_visible(int device_id);
+void device_set_preflight_cb_data(int device_id, void* data);
 
 int device_get_count(int include_hidden);
 int device_get_list(int include_hidden, struct device_info *p);
diff --git a/src/preflight.c b/src/preflight.c
index 283c6d9..b011344 100644
--- a/src/preflight.c
+++ b/src/preflight.c
@@ -30,11 +30,14 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 
 #include <sys/time.h>
 
+#ifdef HAVE_LIBIMOBILEDEVICE
 #include <libimobiledevice/libimobiledevice.h>
 #include <libimobiledevice/lockdown.h>
 #include <libimobiledevice/notification_proxy.h>
+#endif
 
 #include "preflight.h"
+#include "device.h"
 #include "client.h"
 #include "conf.h"
 #include "log.h"
@@ -65,15 +68,12 @@ static void lockdownd_set_untrusted_host_buid(lockdownd_client_t lockdown)
 	free(system_buid);
 }
 
-static void idevice_callback(const idevice_event_t* event, void* userdata)
+void preflight_device_remove_cb(void *data)
 {
-	struct cb_data *cbdata = (struct cb_data*)userdata;
-	idevice_t dev = cbdata->dev;
-	struct idevice_private *_dev = (struct idevice_private*)dev;
-
-	if (event->event == IDEVICE_DEVICE_REMOVE && !strcmp(_dev->udid, event->udid)) {
-		cbdata->is_device_connected = 0;
-	}
+	if (!data)
+		return;
+	struct cb_data *cbdata = (struct cb_data*)data;
+	cbdata->is_device_connected = 0;
 }
 
 static void np_callback(const char* notification, void* userdata)
@@ -246,7 +246,7 @@ retry:
 		cbdata.is_device_connected = 1;
 
 		np_set_notify_callback(np, np_callback, (void*)&cbdata);
-		idevice_event_subscribe(idevice_callback, (void*)&cbdata);
+		device_set_preflight_cb_data(info->id, (void*)&cbdata);
 
 		const char* spec[] = {
 			"com.apple.mobile.lockdown.request_pair",
@@ -267,8 +267,6 @@ retry:
 		}
 		usbmuxd_log(LL_INFO, "%s: Finished waiting for notification from device %s, is_device_connected %d", __func__, _dev->udid, cbdata.is_device_connected);
 
-		idevice_event_unsubscribe();
-
 		if (cbdata.np) {
 			np_client_free(cbdata.np);
 		}
@@ -326,6 +324,10 @@ leave:
 
 	return NULL;
 }
+#else
+void preflight_device_remove_cb(void *data)
+{
+}
 #endif
 
 void preflight_worker_device_add(struct device_info* info)
diff --git a/src/preflight.h b/src/preflight.h
index 62349d1..4c8aa60 100644
--- a/src/preflight.h
+++ b/src/preflight.h
@@ -26,6 +26,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 extern void userpref_get_system_buid(char **systembuid);
 extern void userpref_device_record_get_host_id(const char *udid, char **host_id);
 
+void preflight_device_remove_cb(void *data);
 void preflight_worker_device_add(struct device_info* info);
 
 #endif