[libdmapsharing] Handle invalid content codes in dmap_content_code_dmap_type

[W. Michael Petullo <wmpetullo src gnome org>]

commit 7b97dbb4703639d1fc9d2eb9ea4576669508b013
Author: W. Michael Petullo <mike flyn org>
Date:   Mon Dec 4 22:55:04 2017 -0500

    Handle invalid content codes in dmap_content_code_dmap_type
    
    Signed-off-by: W. Michael Petullo <mike flyn org>

 libdmapsharing/dmap-structure.c |   17 ++++++++++++++---
 libdmapsharing/dmap-structure.h |    3 ++-
 2 files changed, 16 insertions(+), 4 deletions(-)
---
diff --git a/libdmapsharing/dmap-structure.c b/libdmapsharing/dmap-structure.c
index c8e10c6..e68bde2 100644
--- a/libdmapsharing/dmap-structure.c
+++ b/libdmapsharing/dmap-structure.c
@@ -357,7 +357,15 @@ dmap_content_code_name (DMAPContentCode code)
 DMAPType
 dmap_content_code_dmap_type (DMAPContentCode code)
 {
-       return cc_defs[code - 1].type;
+       DMAPType type = DMAP_TYPE_INVALID;
+
+       if (code < sizeof cc_defs / sizeof(DMAPContentCodeDefinition)) {
+               type = cc_defs[code - 1].type;
+       } else {
+               g_warning("Invalid content code: %d\n", code);
+       }
+
+       return type;
 }
 
 const gchar *
@@ -386,6 +394,7 @@ dmap_content_code_gtype (DMAPContentCode code)
        case DMAP_TYPE_POINTER:
                return G_TYPE_POINTER;
        case DMAP_TYPE_CONTAINER:
+       case DMAP_TYPE_INVALID:
        default:
                return G_TYPE_NONE;
        }
@@ -482,6 +491,7 @@ dmap_structure_node_serialize (GNode * node, GByteArray * array)
                        break;
                }
        case DMAP_TYPE_CONTAINER:
+       case DMAP_TYPE_INVALID:
        default:
                break;
        }
@@ -868,8 +878,9 @@ dmap_structure_find_node (GNode * structure, DMAPContentCode code)
 static void
 dmap_item_free (DMAPStructureItem * item)
 {
-       if (dmap_content_code_dmap_type (item->content_code) !=
-           DMAP_TYPE_CONTAINER) {
+       DMAPType type = dmap_content_code_dmap_type (item->content_code);
+
+       if (DMAP_TYPE_INVALID != type && DMAP_TYPE_CONTAINER != type) {
                g_value_unset (&(item->content));
        }
 
diff --git a/libdmapsharing/dmap-structure.h b/libdmapsharing/dmap-structure.h
index e5d59ad..24a9a95 100644
--- a/libdmapsharing/dmap-structure.h
+++ b/libdmapsharing/dmap-structure.h
@@ -228,7 +228,8 @@ typedef enum
        DMAP_TYPE_DATE = 0x000A,
        DMAP_TYPE_VERSION = 0x000B,
        DMAP_TYPE_CONTAINER = 0x000C,
-       DMAP_TYPE_POINTER = 0x002A
+       DMAP_TYPE_POINTER = 0x002A,
+       DMAP_TYPE_INVALID = 0xFFFF
 } DMAPType;
 
 typedef struct _DMAPContentCodeDefinition DMAPContentCodeDefinition;