diff options
Diffstat (limited to 'src/playlist/RssPlaylistPlugin.cxx')
-rw-r--r-- | src/playlist/RssPlaylistPlugin.cxx | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/src/playlist/RssPlaylistPlugin.cxx b/src/playlist/RssPlaylistPlugin.cxx new file mode 100644 index 000000000..9b95683c7 --- /dev/null +++ b/src/playlist/RssPlaylistPlugin.cxx @@ -0,0 +1,327 @@ +/* + * Copyright (C) 2003-2013 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "config.h" +#include "RssPlaylistPlugin.hxx" +#include "PlaylistPlugin.hxx" +#include "input_stream.h" +#include "song.h" +#include "tag.h" + +#include <glib.h> + +#include <assert.h> +#include <string.h> + +#undef G_LOG_DOMAIN +#define G_LOG_DOMAIN "rss" + +/** + * This is the state object for the GLib XML parser. + */ +struct RssParser { + /** + * The list of songs (in reverse order because that's faster + * while adding). + */ + GSList *songs; + + /** + * The current position in the XML file. + */ + enum { + ROOT, ITEM, + } state; + + /** + * The current tag within the "entry" element. This is only + * valid if state==ITEM. TAG_NUM_OF_ITEM_TYPES means there + * is no (known) tag. + */ + enum tag_type tag; + + /** + * The current song. It is allocated after the "location" + * element. + */ + struct song *song; + + RssParser() + :songs(nullptr), state(ROOT) {} +}; + +static const gchar * +get_attribute(const gchar **attribute_names, const gchar **attribute_values, + const gchar *name) +{ + for (unsigned i = 0; attribute_names[i] != NULL; ++i) + if (g_ascii_strcasecmp(attribute_names[i], name) == 0) + return attribute_values[i]; + + return NULL; +} + +static void +rss_start_element(G_GNUC_UNUSED GMarkupParseContext *context, + const gchar *element_name, + const gchar **attribute_names, + const gchar **attribute_values, + gpointer user_data, G_GNUC_UNUSED GError **error) +{ + RssParser *parser = (RssParser *)user_data; + + switch (parser->state) { + case RssParser::ROOT: + if (g_ascii_strcasecmp(element_name, "item") == 0) { + parser->state = RssParser::ITEM; + parser->song = song_remote_new("rss:"); + parser->tag = TAG_NUM_OF_ITEM_TYPES; + } + + break; + + case RssParser::ITEM: + if (g_ascii_strcasecmp(element_name, "enclosure") == 0) { + const gchar *href = get_attribute(attribute_names, + attribute_values, + "url"); + if (href != NULL) { + /* create new song object, and copy + the existing tag over; we cannot + replace the existing song's URI, + because that attribute is + immutable */ + struct song *song = song_remote_new(href); + + if (parser->song != NULL) { + song->tag = parser->song->tag; + parser->song->tag = NULL; + song_free(parser->song); + } + + parser->song = song; + } + } else if (g_ascii_strcasecmp(element_name, "title") == 0) + parser->tag = TAG_TITLE; + else if (g_ascii_strcasecmp(element_name, "itunes:author") == 0) + parser->tag = TAG_ARTIST; + + break; + } +} + +static void +rss_end_element(G_GNUC_UNUSED GMarkupParseContext *context, + const gchar *element_name, + gpointer user_data, G_GNUC_UNUSED GError **error) +{ + RssParser *parser = (RssParser *)user_data; + + switch (parser->state) { + case RssParser::ROOT: + break; + + case RssParser::ITEM: + if (g_ascii_strcasecmp(element_name, "item") == 0) { + if (strcmp(parser->song->uri, "rss:") != 0) + parser->songs = g_slist_prepend(parser->songs, + parser->song); + else + song_free(parser->song); + + parser->state = RssParser::ROOT; + } else + parser->tag = TAG_NUM_OF_ITEM_TYPES; + + break; + } +} + +static void +rss_text(G_GNUC_UNUSED GMarkupParseContext *context, + const gchar *text, gsize text_len, + gpointer user_data, G_GNUC_UNUSED GError **error) +{ + RssParser *parser = (RssParser *)user_data; + + switch (parser->state) { + case RssParser::ROOT: + break; + + case RssParser::ITEM: + if (parser->tag != TAG_NUM_OF_ITEM_TYPES) { + if (parser->song->tag == NULL) + parser->song->tag = tag_new(); + tag_add_item_n(parser->song->tag, parser->tag, + text, text_len); + } + + break; + } +} + +static const GMarkupParser rss_parser = { + rss_start_element, + rss_end_element, + rss_text, + nullptr, + nullptr, +}; + +static void +song_free_callback(gpointer data, G_GNUC_UNUSED gpointer user_data) +{ + struct song *song = (struct song *)data; + + song_free(song); +} + +static void +rss_parser_destroy(gpointer data) +{ + RssParser *parser = (RssParser *)data; + + if (parser->state >= RssParser::ITEM) + song_free(parser->song); + + g_slist_foreach(parser->songs, song_free_callback, NULL); + g_slist_free(parser->songs); +} + +/* + * The playlist object + * + */ + +struct RssPlaylist { + struct playlist_provider base; + + GSList *songs; +}; + +static struct playlist_provider * +rss_open_stream(struct input_stream *is) +{ + RssParser parser; + RssPlaylist *playlist; + GMarkupParseContext *context; + char buffer[1024]; + size_t nbytes; + bool success; + GError *error = NULL; + + /* parse the RSS XML file */ + + context = g_markup_parse_context_new(&rss_parser, + G_MARKUP_TREAT_CDATA_AS_TEXT, + &parser, rss_parser_destroy); + + while (true) { + nbytes = input_stream_lock_read(is, buffer, sizeof(buffer), + &error); + if (nbytes == 0) { + if (error != NULL) { + g_markup_parse_context_free(context); + g_warning("%s", error->message); + g_error_free(error); + return NULL; + } + + break; + } + + success = g_markup_parse_context_parse(context, buffer, nbytes, + &error); + if (!success) { + g_warning("XML parser failed: %s", error->message); + g_error_free(error); + g_markup_parse_context_free(context); + return NULL; + } + } + + success = g_markup_parse_context_end_parse(context, &error); + if (!success) { + g_warning("XML parser failed: %s", error->message); + g_error_free(error); + g_markup_parse_context_free(context); + return NULL; + } + + /* create a #rss_playlist object from the parsed song list */ + + playlist = g_new(RssPlaylist, 1); + playlist_provider_init(&playlist->base, &rss_playlist_plugin); + playlist->songs = g_slist_reverse(parser.songs); + parser.songs = NULL; + + g_markup_parse_context_free(context); + + return &playlist->base; +} + +static void +rss_close(struct playlist_provider *_playlist) +{ + RssPlaylist *playlist = (RssPlaylist *)_playlist; + + g_slist_foreach(playlist->songs, song_free_callback, NULL); + g_slist_free(playlist->songs); + g_free(playlist); +} + +static struct song * +rss_read(struct playlist_provider *_playlist) +{ + RssPlaylist *playlist = (RssPlaylist *)_playlist; + + if (playlist->songs == NULL) + return NULL; + + struct song *song = (struct song *)playlist->songs->data; + playlist->songs = g_slist_remove(playlist->songs, song); + + return song; +} + +static const char *const rss_suffixes[] = { + "rss", + NULL +}; + +static const char *const rss_mime_types[] = { + "application/rss+xml", + "text/xml", + NULL +}; + +const struct playlist_plugin rss_playlist_plugin = { + "rss", + + nullptr, + nullptr, + nullptr, + rss_open_stream, + rss_close, + rss_read, + + nullptr, + rss_suffixes, + rss_mime_types, +}; |