From f9e9089f424217db31c0ad612777bd5a11620c2a Mon Sep 17 00:00:00 2001 From: Max Kellermann Date: Sat, 3 Jan 2009 23:35:30 +0100 Subject: added library for parsing icy-metadata The icy_metadata will be used by the curl input_stream implementation. --- src/Makefile.am | 3 +- src/icy_metadata.c | 175 +++++++++++++++++++++++++++++++++++++++++++++++++++++ src/icy_metadata.h | 98 ++++++++++++++++++++++++++++++ 3 files changed, 275 insertions(+), 1 deletion(-) create mode 100644 src/icy_metadata.c create mode 100644 src/icy_metadata.h diff --git a/src/Makefile.am b/src/Makefile.am index 399534da8..e89905bf2 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -37,6 +37,7 @@ mpd_headers = \ input_stream.h \ input_file.h \ input_curl.h \ + icy_metadata.h \ client.h \ dlist.h \ listen.h \ @@ -264,7 +265,7 @@ endif if HAVE_CURL -mpd_SOURCES += input_curl.c +mpd_SOURCES += input_curl.c icy_metadata.c endif diff --git a/src/icy_metadata.c b/src/icy_metadata.c new file mode 100644 index 000000000..5049d2805 --- /dev/null +++ b/src/icy_metadata.c @@ -0,0 +1,175 @@ +/* + * Copyright (C) 2003-2008 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include "icy_metadata.h" +#include "tag.h" + +#include + +#include +#include + +void +icy_deinit(struct icy_metadata *im) +{ + if (!icy_defined(im)) + return; + + if (im->data_rest == 0 && im->meta_size > 0) + g_free(im->meta_data); + + if (im->tag != NULL) + tag_free(im->tag); +} + +void +icy_reset(struct icy_metadata *im) +{ + if (!icy_defined(im)) + return; + + icy_deinit(im); + + im->data_rest = im->data_size; + im->meta_size = 0; +} + +size_t +icy_data(struct icy_metadata *im, size_t length) +{ + assert(icy_defined(im)); + assert(length > 0); + + if (im->data_rest == 0) + return 0; + + if (length >= im->data_rest) { + length = im->data_rest; + im->data_rest = 0; + } else + im->data_rest -= length; + + return length; +} + +static void +icy_add_item(struct tag *tag, enum tag_type type, const char *value) +{ + size_t length = strlen(value); + + if (length >= 2 && value[0] == '\'' && value[length - 1] == '\'') { + /* strip the single quotes */ + ++value; + length -= 2; + } + + if (length > 0) + tag_add_item_n(tag, type, value, length); +} + +static void +icy_parse_tag_item(struct tag *tag, const char *item) +{ + gchar **p = g_strsplit(item, "=", 0); + + if (p[0] != NULL && p[1] != NULL) { + if (strcmp(p[0], "StreamTitle") == 0) + icy_add_item(tag, TAG_ITEM_TITLE, p[1]); + else + g_debug("unknown icy-tag: '%s'", p[0]); + } + + g_strfreev(p); +} + +static struct tag * +icy_parse_tag(const char *p) +{ + struct tag *tag = tag_new(); + gchar **items = g_strsplit(p, ";", 0); + + for (unsigned i = 0; items[i] != NULL; ++i) + icy_parse_tag_item(tag, items[i]); + + g_strfreev(items); + + return tag; +} + +size_t +icy_meta(struct icy_metadata *im, const void *data, size_t length) +{ + const unsigned char *p = data; + + assert(icy_defined(im)); + assert(im->data_rest == 0); + assert(length > 0); + + if (im->meta_size == 0) { + /* read meta_size from the first byte of a meta + block */ + im->meta_size = *p++ * 16; + if (im->meta_size == 0) { + /* special case: no metadata */ + im->data_rest = im->data_size; + return 1; + } + + /* 1 byte was consumed (must be re-added later for the + return value */ + --length; + + /* initialize metadata reader, allocate enough + memory (+1 for the null terminator) */ + im->meta_position = 0; + im->meta_data = g_malloc(im->meta_size + 1); + } + + assert(im->meta_position < im->meta_size); + + if (length > im->meta_size - im->meta_position) + length = im->meta_size - im->meta_position; + + memcpy(im->meta_data + im->meta_position, data, length); + im->meta_position += length; + + if (p != data) + /* re-add the first byte (which contained meta_size) */ + ++length; + + if (im->meta_position == im->meta_size) { + /* null-terminate the string */ + + im->meta_data[im->meta_size] = 0; + + /* parse */ + + if (im->tag != NULL) + tag_free(im->tag); + + im->tag = icy_parse_tag(im->meta_data); + g_free(im->meta_data); + + /* change back to normal data mode */ + + im->meta_size = 0; + im->data_rest = im->data_size; + } + + return length; +} diff --git a/src/icy_metadata.h b/src/icy_metadata.h new file mode 100644 index 000000000..fd2c7bbc0 --- /dev/null +++ b/src/icy_metadata.h @@ -0,0 +1,98 @@ +/* + * Copyright (C) 2003-2008 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef ICY_METADATA_H +#define ICY_METADATA_H + +#include +#include + +struct icy_metadata { + size_t data_size, data_rest; + + size_t meta_size, meta_position; + char *meta_data; + + struct tag *tag; +}; + +/** + * Initialize a disabled icy_metadata object. + */ +static inline void +icy_clear(struct icy_metadata *im) +{ + im->data_size = 0; +} + +/** + * Initialize an enabled icy_metadata object with the specified + * data_size (from the icy-metaint HTTP response header). + */ +static inline void +icy_start(struct icy_metadata *im, size_t data_size) +{ + im->data_size = im->data_rest = data_size; + im->meta_size = 0; + im->tag = NULL; +} + +/** + * Resets the icy_metadata. Call this after rewinding the stream. + */ +void +icy_reset(struct icy_metadata *im); + +void +icy_deinit(struct icy_metadata *im); + +/** + * Checks whether the icy_metadata object is enabled. + */ +static inline bool +icy_defined(const struct icy_metadata *im) +{ + return im->data_size > 0; +} + +/** + * Evaluates data. Returns the number of bytes of normal data which + * can be read by the caller, but not more than "length". If the + * return value is smaller than "length", the caller should invoke + * icy_meta(). + */ +size_t +icy_data(struct icy_metadata *im, size_t length); + +/** + * Reads metadata from the stream. Returns the number of bytes + * consumed. If the return value is smaller than "length", the caller + * should invoke icy_data(). + */ +size_t +icy_meta(struct icy_metadata *im, const void *data, size_t length); + +static inline struct tag * +icy_tag(struct icy_metadata *im) +{ + struct tag *tag = im->tag; + im->tag = NULL; + return tag; +} + +#endif -- cgit v1.2.3