v4l2: codec: Fix GValue leak

The levels and profiles probe function returned a dynamically allocated GValue
that was leaked. Simplify this by using a stack allocated GValue and a boolean
return value.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/599>

4 files changed, 48 insertions, 41 deletions

diff --git a/sys/v4l2/gstv4l2codec.c b/sys/v4l2/gstv4l2codec.c
index 4ec47a31ab..11223438d8 100644
--- a/sys/v4l2/gstv4l2codec.c
+++ b/sys/v4l2/gstv4l2codec.c
@@ -34,19 +34,19 @@
 
 #include <gst/gst.h>
 
-GValue *
-gst_v4l2_codec_probe_profiles (const GstV4l2Codec * codec, gint video_fd)
+gboolean
+gst_v4l2_codec_probe_profiles (const GstV4l2Codec * codec, gint video_fd,
+    GValue * profiles)
 {
-  GValue *controls = NULL;
   struct v4l2_queryctrl query_ctrl;
+  gboolean ret = FALSE;
 
   memset (&query_ctrl, 0, sizeof (query_ctrl));
   query_ctrl.id = codec->profile_cid;
 
   if (ioctl (video_fd, VIDIOC_QUERYCTRL, &query_ctrl) == 0) {
-    if (query_ctrl.flags & V4L2_CTRL_FLAG_DISABLED) {
-      return NULL;
-    }
+    if (query_ctrl.flags & V4L2_CTRL_FLAG_DISABLED)
+      return FALSE;
 
     if (query_ctrl.type == V4L2_CTRL_TYPE_MENU) {
       struct v4l2_querymenu query_menu;
@@ -54,8 +54,7 @@ gst_v4l2_codec_probe_profiles (const GstV4l2Codec * codec, gint video_fd)
       memset (&query_menu, 0, sizeof (query_menu));
       query_menu.id = query_ctrl.id;
 
-      controls = g_new0 (GValue, 1);
-      g_value_init (controls, GST_TYPE_LIST);
+      g_value_init (profiles, GST_TYPE_LIST);
       for (query_menu.index = query_ctrl.minimum;
           query_menu.index <= query_ctrl.maximum; query_menu.index++) {
         if (ioctl (video_fd, VIDIOC_QUERYMENU, &query_menu) >= 0) {
@@ -64,32 +63,34 @@ gst_v4l2_codec_probe_profiles (const GstV4l2Codec * codec, gint video_fd)
           g_value_init (&value, G_TYPE_STRING);
           g_value_set_string (&value,
               codec->profile_to_string (query_menu.index));
-          gst_value_list_append_and_take_value (controls, &value);
+          gst_value_list_append_and_take_value (profiles, &value);
+          ret = TRUE;
         }
       }
-      if (gst_value_list_get_size (controls) == 0) {
-        g_value_unset (controls);
-        controls = NULL;
+
+      if (gst_value_list_get_size (profiles) == 0) {
+        g_value_unset (profiles);
+        ret = FALSE;
       }
     }
   }
 
-  return controls;
+  return ret;
 }
 
-GValue *
-gst_v4l2_codec_probe_levels (const GstV4l2Codec * codec, gint video_fd)
+gboolean
+gst_v4l2_codec_probe_levels (const GstV4l2Codec * codec, gint video_fd,
+    GValue * levels)
 {
-  GValue *controls = NULL;
   struct v4l2_queryctrl query_ctrl;
+  gboolean ret = FALSE;
 
   memset (&query_ctrl, 0, sizeof (query_ctrl));
   query_ctrl.id = codec->level_cid;
 
   if (ioctl (video_fd, VIDIOC_QUERYCTRL, &query_ctrl) == 0) {
-    if (query_ctrl.flags & V4L2_CTRL_FLAG_DISABLED) {
-      return NULL;
-    }
+    if (query_ctrl.flags & V4L2_CTRL_FLAG_DISABLED)
+      return FALSE;
 
     if (query_ctrl.type == V4L2_CTRL_TYPE_MENU) {
       struct v4l2_querymenu query_menu;
@@ -101,8 +102,7 @@ gst_v4l2_codec_probe_levels (const GstV4l2Codec * codec, gint video_fd)
       if (ioctl (video_fd, VIDIOC_QUERYMENU, &query_menu) >= 0) {
         gint32 i;
 
-        controls = g_new0 (GValue, 1);
-        g_value_init (controls, GST_TYPE_LIST);
+        g_value_init (levels, GST_TYPE_LIST);
 
         /* Assume that all levels below the highest one reported by the driver are supported. */
         for (i = query_ctrl.minimum; i <= query_ctrl.maximum; i++) {
@@ -110,11 +110,17 @@ gst_v4l2_codec_probe_levels (const GstV4l2Codec * codec, gint video_fd)
 
           g_value_init (&value, G_TYPE_STRING);
           g_value_set_string (&value, codec->level_to_string (i));
-          gst_value_list_append_and_take_value (controls, &value);
+          gst_value_list_append_and_take_value (levels, &value);
+          ret = TRUE;
+        }
+
+        if (gst_value_list_get_size (levels) == 0) {
+          g_value_unset (levels);
+          ret = FALSE;
         }
       }
     }
   }
 
-  return controls;
+  return ret;
 }
diff --git a/sys/v4l2/gstv4l2codec.h b/sys/v4l2/gstv4l2codec.h
index 47161dc9ca..23b85a2c64 100644
--- a/sys/v4l2/gstv4l2codec.h
+++ b/sys/v4l2/gstv4l2codec.h
@@ -40,8 +40,10 @@ struct _GstV4l2Codec {
 
 };
 
-GValue * gst_v4l2_codec_probe_profiles(const GstV4l2Codec * codec, gint video_fd);
-GValue * gst_v4l2_codec_probe_levels(const GstV4l2Codec * codec, gint video_fd);
+gboolean gst_v4l2_codec_probe_profiles(const GstV4l2Codec * codec, gint video_fd,
+                                       GValue * value);
+gboolean gst_v4l2_codec_probe_levels(const GstV4l2Codec * codec, gint video_fd,
+                                       GValue * value);
 
 G_END_DECLS
 
diff --git a/sys/v4l2/gstv4l2videodec.c b/sys/v4l2/gstv4l2videodec.c
index 6f26319efe..65a1d1017d 100644
--- a/sys/v4l2/gstv4l2videodec.c
+++ b/sys/v4l2/gstv4l2videodec.c
@@ -1180,16 +1180,16 @@ gst_v4l2_video_dec_register (GstPlugin * plugin, const gchar * basename,
     }
 
     if (cdata->codec != NULL) {
-      GValue *value = gst_v4l2_codec_probe_levels (cdata->codec, video_fd);
-      if (value != NULL) {
-        gst_caps_set_value (cdata->sink_caps, "level", value);
-        g_value_unset (value);
+      GValue value = G_VALUE_INIT;
+
+      if (gst_v4l2_codec_probe_levels (cdata->codec, video_fd, &value)) {
+        gst_caps_set_value (cdata->sink_caps, "level", &value);
+        g_value_unset (&value);
       }
 
-      value = gst_v4l2_codec_probe_profiles (cdata->codec, video_fd);
-      if (value != NULL) {
-        gst_caps_set_value (cdata->sink_caps, "profile", value);
-        g_value_unset (value);
+      if (gst_v4l2_codec_probe_profiles (cdata->codec, video_fd, &value)) {
+        gst_caps_set_value (cdata->sink_caps, "profile", &value);
+        g_value_unset (&value);
       }
     }
 
diff --git a/sys/v4l2/gstv4l2videoenc.c b/sys/v4l2/gstv4l2videoenc.c
index d1421dab5e..f89d021963 100644
--- a/sys/v4l2/gstv4l2videoenc.c
+++ b/sys/v4l2/gstv4l2videoenc.c
@@ -1174,18 +1174,17 @@ gst_v4l2_video_enc_register (GstPlugin * plugin, GType type,
   GType subtype;
   gchar *type_name;
   GstV4l2VideoEncCData *cdata;
+  GValue value = G_VALUE_INIT;
 
   if (codec != NULL && video_fd != -1) {
-    GValue *value = gst_v4l2_codec_probe_levels (codec, video_fd);
-    if (value != NULL) {
-      gst_caps_set_value (src_caps, "level", value);
-      g_value_unset (value);
+    if (gst_v4l2_codec_probe_levels (codec, video_fd, &value)) {
+      gst_caps_set_value (src_caps, "level", &value);
+      g_value_unset (&value);
     }
 
-    value = gst_v4l2_codec_probe_profiles (codec, video_fd);
-    if (value != NULL) {
-      gst_caps_set_value (src_caps, "profile", value);
-      g_value_unset (value);
+    if (gst_v4l2_codec_probe_profiles (codec, video_fd, &value)) {
+      gst_caps_set_value (src_caps, "profile", &value);
+      g_value_unset (&value);
     }
   }