[vlc-devel] [PATCH 01/20] input: item: add input_item_Parse

[Thomas Guillem]

This function doesn't use a background thread, contrary to
libvlc_MetadataRequest(). It will be used by the Medialibray that has its own
background thread.
---
 include/vlc_input_item.h | 60 +++++++++++++++++++++++++++++++++++
 src/input/item.c         | 67 ++++++++++++++++++++++++++++++++++++++++
 src/libvlccore.sym       |  2 ++
 3 files changed, 129 insertions(+)

diff --git a/include/vlc_input_item.h b/include/vlc_input_item.h
index 5ae437c13f..272f774306 100644
--- a/include/vlc_input_item.h
+++ b/include/vlc_input_item.h
@@ -371,6 +371,66 @@ VLC_API input_item_t *input_item_Hold(input_item_t *);
 /** Releases an input item, i.e. decrements its reference counter. */
 VLC_API void input_item_Release(input_item_t *);
 
+/**
+ * input item parser opaque structure
+ */
+typedef struct input_item_parser_t input_item_parser_t;
+
+/**
+ * input item parser callbacks
+ */
+typedef struct input_item_parser_cbs_t
+{
+    /**
+     * Event received when the parser ends
+     *
+     * @note this callback is mandatory.
+     *
+     * @param item the parsed item
+     * @param ret VLC_SUCCESS in case of success, an error otherwise
+     * @param userdata user data set by input_item_Parse()
+     */
+    void (*on_ended)(input_item_t *item, int ret, void *userdata);
+
+    /**
+     * Event received when a new subtree is added
+     *
+     * @note this callback is optional.
+     *
+     * @param item the parsed item
+     * @param subtree sub items of the current item
+     * @param userdata user data set by input_item_Parse()
+     */
+    void (*on_subtree_added)(input_item_t *item, input_item_node_t *subtree, void *userdata);
+} input_item_parser_cbs_t;
+
+/**
+ * Parse an item
+ *
+ * @note the parsing is done asynchronously. The user can call
+ * input_item_parser_Release() before receiving the on_ended() event in order
+ * to interrupt it.
+ *
+ * @param item the item to parse
+ * @param parent the parent obj
+ * @param cbs callbacks to be notified of the end of the parsing
+ * @param userdata opaque data user by parser callbacks
+ *
+ * @return a parser instance or NULL in case of error, the parser needs to be
+ * released with input_item_parser_Release()
+ */
+VLC_API input_item_parser_t *
+input_item_Parse(input_item_t *item, vlc_object_t *parent,
+                 const input_item_parser_cbs_t *cbs, void *userdata) VLC_USED;
+
+/**
+ * Release (and interrupt if needed) a parser
+ *
+ * @param parser the parser returned by input_item_Parse
+ */
+VLC_API void
+input_item_parser_Release(input_item_parser_t *parser);
+
 typedef enum input_item_meta_request_option_t
 {
     META_REQUEST_OPTION_NONE          = 0x00,
diff --git a/src/input/item.c b/src/input/item.c
index 830c79895f..ce58b90122 100644
--- a/src/input/item.c
+++ b/src/input/item.c
@@ -1325,6 +1325,73 @@ void input_item_UpdateTracksInfo(input_item_t *item, const es_format_t *fmt)
     vlc_mutex_unlock( &item->lock );
 }
 
+struct input_item_parser_t
+{
+    input_thread_t *input;
+    input_state_e state;
+    const input_item_parser_cbs_t *cbs;
+    void *userdata;
+};
+
+static void
+input_item_parser_InputEvent(input_thread_t *input,
+                             const struct vlc_input_event *event, void *parser_)
+{
+    input_item_parser_t *parser = parser_;
+
+    switch (event->type)
+    {
+        case INPUT_EVENT_STATE:
+            parser->state = event->state;
+            break;
+        case INPUT_EVENT_DEAD:
+        {
+            int ret = parser->state == END_S ? VLC_SUCCESS : VLC_EGENERIC;
+            parser->cbs->on_ended(input_GetItem(input), ret, parser->userdata);
+            break;
+        }
+        case INPUT_EVENT_SUBITEMS:
+            if (parser->cbs->on_subtree_added)
+                parser->cbs->on_subtree_added(input_GetItem(input),
+                                              event->subitems, parser->userdata);
+            break;
+        default:
+            break;
+    }
+}
+
+input_item_parser_t *
+input_item_Parse(input_item_t *item, vlc_object_t *obj,
+                 const input_item_parser_cbs_t *cbs, void *userdata)
+{
+    assert(cbs && cbs->on_ended);
+    input_item_parser_t *parser = malloc(sizeof(*parser));
+    if (!parser)
+        return NULL;
+
+    parser->state = INIT_S;
+    parser->cbs = cbs;
+    parser->userdata = userdata;
+    parser->input = input_CreatePreparser(obj, input_item_parser_InputEvent,
+                                          parser, item);
+    if (!parser->input || input_Start(parser->input))
+    {
+        if (parser->input)
+            input_Close(parser->input);
+        free(parser);
+        return NULL;
+    }
+    return parser;
+}
+
+void
+input_item_parser_Release(input_item_parser_t *parser)
+{
+    input_Stop(parser->input);
+    input_Close(parser->input);
+    free(parser);
+}
+
 static int rdh_compar_type(input_item_t *p1, input_item_t *p2)
 {
     if (p1->i_type != p2->i_type)
diff --git a/src/libvlccore.sym b/src/libvlccore.sym
index 87190a3573..ae7cc6d8b4 100644
--- a/src/libvlccore.sym
+++ b/src/libvlccore.sym
@@ -207,6 +207,8 @@ input_item_WriteMeta
 input_item_slave_GetType
 input_item_slave_New
 input_item_AddSlave
+input_item_Parse
+input_item_parser_Release
 input_Read
 input_resource_New
 input_resource_Release
-- 
2.20.1