From: Jeongmo Yang <jm80.yang@samsung.com>
Date: Wed, 19 Jun 2024 05:02:00 +0000 (+0900)
Subject: Add defensive code for clearing locked mutex
X-Git-Tag: accepted/tizen/8.0/unified/20240701.172933^0
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6338e88f11ff59631f4ef62350b326bc572d2c27;p=platform%2Fcore%2Fapi%2Fcamera.git

Add defensive code for clearing locked mutex

- The mutex can be cleared although it's locked while calling client user callback.
- Add defensive code to avoid clearing locked mutex.

[Version] 0.4.120
[Issue Type] Improvement

Change-Id: Ib6abaeba5a05c5cdb7f5667c4719c6a2e89bdfe2
Signed-off-by: Jeongmo Yang <jm80.yang@samsung.com>
---

diff --git a/packaging/capi-media-camera.spec b/packaging/capi-media-camera.spec
index 147ca36..59b59ee 100644
--- a/packaging/capi-media-camera.spec
+++ b/packaging/capi-media-camera.spec
@@ -1,6 +1,6 @@
 Name:       capi-media-camera
 Summary:    A Camera API
-Version:    0.4.119
+Version:    0.4.120
 Release:    0
 Group:      Multimedia/API
 License:    Apache-2.0
diff --git a/src/camera.c b/src/camera.c
index bd33b1e..c4b4291 100644
--- a/src/camera.c
+++ b/src/camera.c
@@ -1748,6 +1748,8 @@ static void __camera_client_user_callback(camera_cb_info_s *cb_info, char *recv_
 	}
 
 	g_mutex_unlock(&cb_info->user_cb_mutex[event]);
+
+	CAM_LOG_DEBUG("done - event[%d]", event);
 }
 
 static gboolean __camera_idle_event_callback(gpointer data)
@@ -2395,8 +2397,17 @@ static void __camera_mutex_cond_clear(camera_cb_info_s *cb_info)
 	g_mutex_clear(&cb_info->mp_data_mutex);
 	g_mutex_clear(&cb_info->bridge_lock);
 
-	for (i = 0 ; i < MUSE_CAMERA_EVENT_TYPE_NUM ; i++)
+	for (i = 0 ; i < MUSE_CAMERA_EVENT_TYPE_NUM ; i++) {
+		/* The mutex can be locked when the user callback is called in idle callback.
+		   This code will wait until it's unlocked and avoid crash by clearing locked mutex. */
+		if (!g_mutex_trylock(&cb_info->user_cb_mutex[i])) {
+			CAM_LOG_WARNING("user_cb_mutex[%d] is locked somewhere", i);
+			g_mutex_lock(&cb_info->user_cb_mutex[i]);
+		}
+
+		g_mutex_unlock(&cb_info->user_cb_mutex[i]);
 		g_mutex_clear(&cb_info->user_cb_mutex[i]);
+	}
 
 	for (i = 0 ; i < MUSE_CAMERA_API_MAX ; i++) {
 		g_mutex_clear(&cb_info->api_mutex[i]);