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/unified/20240701.191826~3
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b35138e5861ab9c47ff1f921939cda43f0e15802;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] 1.0.2
[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 29928a6..75d5fa3 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:    1.0.1
+Version:    1.0.2
 Release:    0
 Group:      Multimedia/API
 License:    Apache-2.0
diff --git a/src/camera.c b/src/camera.c
index 1f4fa41..24f0193 100644
--- a/src/camera.c
+++ b/src/camera.c
@@ -1713,6 +1713,8 @@ static void __camera_client_user_callback(camera_cb_info_s *cb_info, char *recv_
 		CAM_LOG_WARNING("unhandled event %d", event);
 		break;
 	}
+
+	CAM_LOG_DEBUG("done - event[%d]", event);
 }
 
 static gboolean __camera_idle_event_callback(gpointer data)
@@ -2367,8 +2369,17 @@ static void __camera_mutex_cond_clear(camera_cb_info_s *cb_info)
 	g_mutex_clear(&cb_info->mp_data_lock);
 	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_lock[i])) {
+			CAM_LOG_WARNING("user_cb_lock[%d] is locked somewhere", i);
+			g_mutex_lock(&cb_info->user_cb_lock[i]);
+		}
+
+		g_mutex_unlock(&cb_info->user_cb_lock[i]);
 		g_mutex_clear(&cb_info->user_cb_lock[i]);
+	}
 
 	for (i = 0 ; i < MUSE_CAMERA_API_MAX ; i++) {
 		g_mutex_clear(&cb_info->api_lock[i]);