cannam@85: /*
cannam@85:  * libid3tag - ID3 tag manipulation library
cannam@85:  * Copyright (C) 2000-2004 Underbit Technologies, Inc.
cannam@85:  *
cannam@85:  * This program is free software; you can redistribute it and/or modify
cannam@85:  * it under the terms of the GNU General Public License as published by
cannam@85:  * the Free Software Foundation; either version 2 of the License, or
cannam@85:  * (at your option) any later version.
cannam@85:  *
cannam@85:  * This program is distributed in the hope that it will be useful,
cannam@85:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
cannam@85:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
cannam@85:  * GNU General Public License for more details.
cannam@85:  *
cannam@85:  * You should have received a copy of the GNU General Public License
cannam@85:  * along with this program; if not, write to the Free Software
cannam@85:  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
cannam@85:  *
cannam@85:  * $Id: tag.c,v 1.20 2004/02/17 02:04:10 rob Exp $
cannam@85:  */
cannam@85: 
cannam@85: # ifdef HAVE_CONFIG_H
cannam@85: #  include "config.h"
cannam@85: # endif
cannam@85: 
cannam@85: # include "global.h"
cannam@85: 
cannam@85: # include <string.h>
cannam@85: # include <stdlib.h>
cannam@85: 
cannam@85: # ifdef HAVE_ASSERT_H
cannam@85: #  include <assert.h>
cannam@85: # endif
cannam@85: 
cannam@85: # include "id3tag.h"
cannam@85: # include "tag.h"
cannam@85: # include "frame.h"
cannam@85: # include "compat.h"
cannam@85: # include "parse.h"
cannam@85: # include "render.h"
cannam@85: # include "latin1.h"
cannam@85: # include "ucs4.h"
cannam@85: # include "genre.h"
cannam@85: # include "crc.h"
cannam@85: # include "field.h"
cannam@85: # include "util.h"
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->new()
cannam@85:  * DESCRIPTION:	allocate and return a new, empty tag
cannam@85:  */
cannam@85: struct id3_tag *id3_tag_new(void)
cannam@85: {
cannam@85:   struct id3_tag *tag;
cannam@85: 
cannam@85:   tag = malloc(sizeof(*tag));
cannam@85:   if (tag) {
cannam@85:     tag->refcount      = 0;
cannam@85:     tag->version       = ID3_TAG_VERSION;
cannam@85:     tag->flags         = 0;
cannam@85:     tag->extendedflags = 0;
cannam@85:     tag->restrictions  = 0;
cannam@85:     tag->options       = /* ID3_TAG_OPTION_UNSYNCHRONISATION | */
cannam@85:                          ID3_TAG_OPTION_COMPRESSION | ID3_TAG_OPTION_CRC;
cannam@85:     tag->nframes       = 0;
cannam@85:     tag->frames        = 0;
cannam@85:     tag->paddedsize    = 0;
cannam@85:   }
cannam@85: 
cannam@85:   return tag;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->delete()
cannam@85:  * DESCRIPTION:	destroy a tag and deallocate all associated memory
cannam@85:  */
cannam@85: void id3_tag_delete(struct id3_tag *tag)
cannam@85: {
cannam@85:   assert(tag);
cannam@85: 
cannam@85:   if (tag->refcount == 0) {
cannam@85:     id3_tag_clearframes(tag);
cannam@85: 
cannam@85:     if (tag->frames)
cannam@85:       free(tag->frames);
cannam@85: 
cannam@85:     free(tag);
cannam@85:   }
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->addref()
cannam@85:  * DESCRIPTION:	add an external reference to a tag
cannam@85:  */
cannam@85: void id3_tag_addref(struct id3_tag *tag)
cannam@85: {
cannam@85:   assert(tag);
cannam@85: 
cannam@85:   ++tag->refcount;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->delref()
cannam@85:  * DESCRIPTION:	remove an external reference to a tag
cannam@85:  */
cannam@85: void id3_tag_delref(struct id3_tag *tag)
cannam@85: {
cannam@85:   assert(tag && tag->refcount > 0);
cannam@85: 
cannam@85:   --tag->refcount;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->version()
cannam@85:  * DESCRIPTION:	return the tag's original ID3 version number
cannam@85:  */
cannam@85: unsigned int id3_tag_version(struct id3_tag const *tag)
cannam@85: {
cannam@85:   assert(tag);
cannam@85: 
cannam@85:   return tag->version;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->options()
cannam@85:  * DESCRIPTION:	get or set tag options
cannam@85:  */
cannam@85: int id3_tag_options(struct id3_tag *tag, int mask, int values)
cannam@85: {
cannam@85:   assert(tag);
cannam@85: 
cannam@85:   if (mask)
cannam@85:     tag->options = (tag->options & ~mask) | (values & mask);
cannam@85: 
cannam@85:   return tag->options;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->setlength()
cannam@85:  * DESCRIPTION:	set the minimum rendered tag size
cannam@85:  */
cannam@85: void id3_tag_setlength(struct id3_tag *tag, id3_length_t length)
cannam@85: {
cannam@85:   assert(tag);
cannam@85: 
cannam@85:   tag->paddedsize = length;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->clearframes()
cannam@85:  * DESCRIPTION:	detach and delete all frames associated with a tag
cannam@85:  */
cannam@85: void id3_tag_clearframes(struct id3_tag *tag)
cannam@85: {
cannam@85:   unsigned int i;
cannam@85: 
cannam@85:   assert(tag);
cannam@85: 
cannam@85:   for (i = 0; i < tag->nframes; ++i) {
cannam@85:     id3_frame_delref(tag->frames[i]);
cannam@85:     id3_frame_delete(tag->frames[i]);
cannam@85:   }
cannam@85: 
cannam@85:   tag->nframes = 0;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->attachframe()
cannam@85:  * DESCRIPTION:	attach a frame to a tag
cannam@85:  */
cannam@85: int id3_tag_attachframe(struct id3_tag *tag, struct id3_frame *frame)
cannam@85: {
cannam@85:   struct id3_frame **frames;
cannam@85: 
cannam@85:   assert(tag && frame);
cannam@85: 
cannam@85:   frames = realloc(tag->frames, (tag->nframes + 1) * sizeof(*frames));
cannam@85:   if (frames == 0)
cannam@85:     return -1;
cannam@85: 
cannam@85:   tag->frames = frames;
cannam@85:   tag->frames[tag->nframes++] = frame;
cannam@85: 
cannam@85:   id3_frame_addref(frame);
cannam@85: 
cannam@85:   return 0;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->detachframe()
cannam@85:  * DESCRIPTION:	detach (but don't delete) a frame from a tag
cannam@85:  */
cannam@85: int id3_tag_detachframe(struct id3_tag *tag, struct id3_frame *frame)
cannam@85: {
cannam@85:   unsigned int i;
cannam@85: 
cannam@85:   assert(tag && frame);
cannam@85: 
cannam@85:   for (i = 0; i < tag->nframes; ++i) {
cannam@85:     if (tag->frames[i] == frame)
cannam@85:       break;
cannam@85:   }
cannam@85: 
cannam@85:   if (i == tag->nframes)
cannam@85:     return -1;
cannam@85: 
cannam@85:   --tag->nframes;
cannam@85:   while (i++ < tag->nframes)
cannam@85:     tag->frames[i - 1] = tag->frames[i];
cannam@85: 
cannam@85:   id3_frame_delref(frame);
cannam@85: 
cannam@85:   return 0;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->findframe()
cannam@85:  * DESCRIPTION:	find in a tag the nth (0-based) frame with the given frame ID
cannam@85:  */
cannam@85: struct id3_frame *id3_tag_findframe(struct id3_tag const *tag,
cannam@85: 				    char const *id, unsigned int index)
cannam@85: {
cannam@85:   unsigned int len, i;
cannam@85: 
cannam@85:   assert(tag);
cannam@85: 
cannam@85:   if (id == 0 || *id == 0)
cannam@85:     return (index < tag->nframes) ? tag->frames[index] : 0;
cannam@85: 
cannam@85:   len = strlen(id);
cannam@85: 
cannam@85:   if (len == 4) {
cannam@85:     struct id3_compat const *compat;
cannam@85: 
cannam@85:     compat = id3_compat_lookup(id, len);
cannam@85:     if (compat && compat->equiv && !compat->translate) {
cannam@85:       id  = compat->equiv;
cannam@85:       len = strlen(id);
cannam@85:     }
cannam@85:   }
cannam@85: 
cannam@85:   for (i = 0; i < tag->nframes; ++i) {
cannam@85:     if (strncmp(tag->frames[i]->id, id, len) == 0 && index-- == 0)
cannam@85:       return tag->frames[i];
cannam@85:   }
cannam@85: 
cannam@85:   return 0;
cannam@85: }
cannam@85: 
cannam@85: enum tagtype {
cannam@85:   TAGTYPE_NONE = 0,
cannam@85:   TAGTYPE_ID3V1,
cannam@85:   TAGTYPE_ID3V2,
cannam@85:   TAGTYPE_ID3V2_FOOTER
cannam@85: };
cannam@85: 
cannam@85: static
cannam@85: enum tagtype tagtype(id3_byte_t const *data, id3_length_t length)
cannam@85: {
cannam@85:   if (length >= 3 &&
cannam@85:       data[0] == 'T' && data[1] == 'A' && data[2] == 'G')
cannam@85:     return TAGTYPE_ID3V1;
cannam@85: 
cannam@85:   if (length >= 10 &&
cannam@85:       ((data[0] == 'I' && data[1] == 'D' && data[2] == '3') ||
cannam@85:        (data[0] == '3' && data[1] == 'D' && data[2] == 'I')) &&
cannam@85:       data[3] < 0xff && data[4] < 0xff &&
cannam@85:       data[6] < 0x80 && data[7] < 0x80 && data[8] < 0x80 && data[9] < 0x80)
cannam@85:     return data[0] == 'I' ? TAGTYPE_ID3V2 : TAGTYPE_ID3V2_FOOTER;
cannam@85: 
cannam@85:   return TAGTYPE_NONE;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: void parse_header(id3_byte_t const **ptr,
cannam@85: 		  unsigned int *version, int *flags, id3_length_t *size)
cannam@85: {
cannam@85:   *ptr += 3;
cannam@85: 
cannam@85:   *version = id3_parse_uint(ptr, 2);
cannam@85:   *flags   = id3_parse_uint(ptr, 1);
cannam@85:   *size    = id3_parse_syncsafe(ptr, 4);
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->query()
cannam@85:  * DESCRIPTION:	if a tag begins at the given location, return its size
cannam@85:  */
cannam@85: signed long id3_tag_query(id3_byte_t const *data, id3_length_t length)
cannam@85: {
cannam@85:   unsigned int version;
cannam@85:   int flags;
cannam@85:   id3_length_t size;
cannam@85: 
cannam@85:   assert(data);
cannam@85: 
cannam@85:   switch (tagtype(data, length)) {
cannam@85:   case TAGTYPE_ID3V1:
cannam@85:     return 128;
cannam@85: 
cannam@85:   case TAGTYPE_ID3V2:
cannam@85:     parse_header(&data, &version, &flags, &size);
cannam@85: 
cannam@85:     if (flags & ID3_TAG_FLAG_FOOTERPRESENT)
cannam@85:       size += 10;
cannam@85: 
cannam@85:     return 10 + size;
cannam@85: 
cannam@85:   case TAGTYPE_ID3V2_FOOTER:
cannam@85:     parse_header(&data, &version, &flags, &size);
cannam@85:     return -size - 10;
cannam@85: 
cannam@85:   case TAGTYPE_NONE:
cannam@85:     break;
cannam@85:   }
cannam@85: 
cannam@85:   return 0;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: void trim(char *str)
cannam@85: {
cannam@85:   char *ptr;
cannam@85: 
cannam@85:   ptr = str + strlen(str);
cannam@85:   while (ptr > str && ptr[-1] == ' ')
cannam@85:     --ptr;
cannam@85: 
cannam@85:   *ptr = 0;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: int v1_attachstr(struct id3_tag *tag, char const *id,
cannam@85: 		 char *text, unsigned long number)
cannam@85: {
cannam@85:   struct id3_frame *frame;
cannam@85:   id3_ucs4_t ucs4[31];
cannam@85: 
cannam@85:   if (text) {
cannam@85:     trim(text);
cannam@85:     if (*text == 0)
cannam@85:       return 0;
cannam@85:   }
cannam@85: 
cannam@85:   frame = id3_frame_new(id);
cannam@85:   if (frame == 0)
cannam@85:     return -1;
cannam@85: 
cannam@85:   if (id3_field_settextencoding(&frame->fields[0],
cannam@85: 				ID3_FIELD_TEXTENCODING_ISO_8859_1) == -1)
cannam@85:     goto fail;
cannam@85: 
cannam@85:   if (text)
cannam@85:     id3_latin1_decode(text, ucs4);
cannam@85:   else
cannam@85:     id3_ucs4_putnumber(ucs4, number);
cannam@85: 
cannam@85:   if (strcmp(id, ID3_FRAME_COMMENT) == 0) {
cannam@85:     if (id3_field_setlanguage(&frame->fields[1], "XXX") == -1 ||
cannam@85: 	id3_field_setstring(&frame->fields[2], id3_ucs4_empty) == -1 ||
cannam@85: 	id3_field_setfullstring(&frame->fields[3], ucs4) == -1)
cannam@85:       goto fail;
cannam@85:   }
cannam@85:   else {
cannam@85:     id3_ucs4_t *ptr = ucs4;
cannam@85: 
cannam@85:     if (id3_field_setstrings(&frame->fields[1], 1, &ptr) == -1)
cannam@85:       goto fail;
cannam@85:   }
cannam@85: 
cannam@85:   if (id3_tag_attachframe(tag, frame) == -1)
cannam@85:     goto fail;
cannam@85: 
cannam@85:   return 0;
cannam@85: 
cannam@85:  fail:
cannam@85:   id3_frame_delete(frame);
cannam@85:   return -1;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: struct id3_tag *v1_parse(id3_byte_t const *data)
cannam@85: {
cannam@85:   struct id3_tag *tag;
cannam@85: 
cannam@85:   tag = id3_tag_new();
cannam@85:   if (tag) {
cannam@85:     char title[31], artist[31], album[31], year[5], comment[31];
cannam@85:     unsigned int genre, track;
cannam@85: 
cannam@85:     tag->version = 0x0100;
cannam@85: 
cannam@85:     tag->options |=  ID3_TAG_OPTION_ID3V1;
cannam@85:     tag->options &= ~ID3_TAG_OPTION_COMPRESSION;
cannam@85: 
cannam@85:     tag->restrictions =
cannam@85:       ID3_TAG_RESTRICTION_TEXTENCODING_LATIN1_UTF8 |
cannam@85:       ID3_TAG_RESTRICTION_TEXTSIZE_30_CHARS;
cannam@85: 
cannam@85:     title[30] = artist[30] = album[30] = year[4] = comment[30] = 0;
cannam@85: 
cannam@85:     memcpy(title,   &data[3],  30);
cannam@85:     memcpy(artist,  &data[33], 30);
cannam@85:     memcpy(album,   &data[63], 30);
cannam@85:     memcpy(year,    &data[93],  4);
cannam@85:     memcpy(comment, &data[97], 30);
cannam@85: 
cannam@85:     genre = data[127];
cannam@85: 
cannam@85:     track = 0;
cannam@85:     if (comment[28] == 0 && comment[29] != 0) {
cannam@85:       track = comment[29];
cannam@85:       tag->version = 0x0101;
cannam@85:     }
cannam@85: 
cannam@85:     /* populate tag frames */
cannam@85: 
cannam@85:     if (v1_attachstr(tag, ID3_FRAME_TITLE,  title,  0) == -1 ||
cannam@85: 	v1_attachstr(tag, ID3_FRAME_ARTIST, artist, 0) == -1 ||
cannam@85: 	v1_attachstr(tag, ID3_FRAME_ALBUM,  album,  0) == -1 ||
cannam@85: 	v1_attachstr(tag, ID3_FRAME_YEAR,   year,   0) == -1 ||
cannam@85: 	(track        && v1_attachstr(tag, ID3_FRAME_TRACK, 0, track) == -1) ||
cannam@85: 	(genre < 0xff && v1_attachstr(tag, ID3_FRAME_GENRE, 0, genre) == -1) ||
cannam@85: 	v1_attachstr(tag, ID3_FRAME_COMMENT, comment, 0) == -1) {
cannam@85:       id3_tag_delete(tag);
cannam@85:       tag = 0;
cannam@85:     }
cannam@85:   }
cannam@85: 
cannam@85:   return tag;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: struct id3_tag *v2_parse(id3_byte_t const *ptr)
cannam@85: {
cannam@85:   struct id3_tag *tag;
cannam@85:   id3_byte_t *mem = 0;
cannam@85: 
cannam@85:   tag = id3_tag_new();
cannam@85:   if (tag) {
cannam@85:     id3_byte_t const *end;
cannam@85:     id3_length_t size;
cannam@85: 
cannam@85:     parse_header(&ptr, &tag->version, &tag->flags, &size);
cannam@85: 
cannam@85:     tag->paddedsize = 10 + size;
cannam@85: 
cannam@85:     if ((tag->flags & ID3_TAG_FLAG_UNSYNCHRONISATION) &&
cannam@85: 	ID3_TAG_VERSION_MAJOR(tag->version) < 4) {
cannam@85:       mem = malloc(size);
cannam@85:       if (mem == 0)
cannam@85: 	goto fail;
cannam@85: 
cannam@85:       memcpy(mem, ptr, size);
cannam@85: 
cannam@85:       size = id3_util_deunsynchronise(mem, size);
cannam@85:       ptr  = mem;
cannam@85:     }
cannam@85: 
cannam@85:     end = ptr + size;
cannam@85: 
cannam@85:     if (tag->flags & ID3_TAG_FLAG_EXTENDEDHEADER) {
cannam@85:       switch (ID3_TAG_VERSION_MAJOR(tag->version)) {
cannam@85:       case 2:
cannam@85: 	goto fail;
cannam@85: 
cannam@85:       case 3:
cannam@85: 	{
cannam@85: 	  id3_byte_t const *ehptr, *ehend;
cannam@85: 	  id3_length_t ehsize;
cannam@85: 
cannam@85: 	  enum {
cannam@85: 	    EH_FLAG_CRC = 0x8000  /* CRC data present */
cannam@85: 	  };
cannam@85: 
cannam@85: 	  if (end - ptr < 4)
cannam@85: 	    goto fail;
cannam@85: 
cannam@85: 	  ehsize = id3_parse_uint(&ptr, 4);
cannam@85: 
cannam@85: 	  if (ehsize > end - ptr)
cannam@85: 	    goto fail;
cannam@85: 
cannam@85: 	  ehptr = ptr;
cannam@85: 	  ehend = ptr + ehsize;
cannam@85: 
cannam@85: 	  ptr = ehend;
cannam@85: 
cannam@85: 	  if (ehend - ehptr >= 6) {
cannam@85: 	    int ehflags;
cannam@85: 	    id3_length_t padsize;
cannam@85: 
cannam@85: 	    ehflags = id3_parse_uint(&ehptr, 2);
cannam@85: 	    padsize = id3_parse_uint(&ehptr, 4);
cannam@85: 
cannam@85: 	    if (padsize > end - ptr)
cannam@85: 	      goto fail;
cannam@85: 
cannam@85: 	    end -= padsize;
cannam@85: 
cannam@85: 	    if (ehflags & EH_FLAG_CRC) {
cannam@85: 	      unsigned long crc;
cannam@85: 
cannam@85: 	      if (ehend - ehptr < 4)
cannam@85: 		goto fail;
cannam@85: 
cannam@85: 	      crc = id3_parse_uint(&ehptr, 4);
cannam@85: 
cannam@85: 	      if (crc != id3_crc_compute(ptr, end - ptr))
cannam@85: 		goto fail;
cannam@85: 
cannam@85: 	      tag->extendedflags |= ID3_TAG_EXTENDEDFLAG_CRCDATAPRESENT;
cannam@85: 	    }
cannam@85: 	  }
cannam@85: 	}
cannam@85: 	break;
cannam@85: 
cannam@85:       case 4:
cannam@85: 	{
cannam@85: 	  id3_byte_t const *ehptr, *ehend;
cannam@85: 	  id3_length_t ehsize;
cannam@85: 	  unsigned int bytes;
cannam@85: 
cannam@85: 	  if (end - ptr < 4)
cannam@85: 	    goto fail;
cannam@85: 
cannam@85: 	  ehptr  = ptr;
cannam@85: 	  ehsize = id3_parse_syncsafe(&ptr, 4);
cannam@85: 
cannam@85: 	  if (ehsize < 6 || ehsize > end - ehptr)
cannam@85: 	    goto fail;
cannam@85: 
cannam@85: 	  ehend = ehptr + ehsize;
cannam@85: 
cannam@85: 	  bytes = id3_parse_uint(&ptr, 1);
cannam@85: 
cannam@85: 	  if (bytes < 1 || bytes > ehend - ptr)
cannam@85: 	    goto fail;
cannam@85: 
cannam@85: 	  ehptr = ptr + bytes;
cannam@85: 
cannam@85: 	  /* verify extended header size */
cannam@85: 	  {
cannam@85: 	    id3_byte_t const *flagsptr = ptr, *dataptr = ehptr;
cannam@85: 	    unsigned int datalen;
cannam@85: 	    int ehflags;
cannam@85: 
cannam@85: 	    while (bytes--) {
cannam@85: 	      for (ehflags = id3_parse_uint(&flagsptr, 1); ehflags;
cannam@85: 		   ehflags = (ehflags << 1) & 0xff) {
cannam@85: 		if (ehflags & 0x80) {
cannam@85: 		  if (dataptr == ehend)
cannam@85: 		    goto fail;
cannam@85: 		  datalen = id3_parse_uint(&dataptr, 1);
cannam@85: 		  if (datalen > 0x7f || datalen > ehend - dataptr)
cannam@85: 		    goto fail;
cannam@85: 		  dataptr += datalen;
cannam@85: 		}
cannam@85: 	      }
cannam@85: 	    }
cannam@85: 	  }
cannam@85: 
cannam@85: 	  tag->extendedflags = id3_parse_uint(&ptr, 1);
cannam@85: 
cannam@85: 	  ptr = ehend;
cannam@85: 
cannam@85: 	  if (tag->extendedflags & ID3_TAG_EXTENDEDFLAG_TAGISANUPDATE) {
cannam@85: 	    bytes  = id3_parse_uint(&ehptr, 1);
cannam@85: 	    ehptr += bytes;
cannam@85: 	  }
cannam@85: 
cannam@85: 	  if (tag->extendedflags & ID3_TAG_EXTENDEDFLAG_CRCDATAPRESENT) {
cannam@85: 	    unsigned long crc;
cannam@85: 
cannam@85: 	    bytes = id3_parse_uint(&ehptr, 1);
cannam@85: 	    if (bytes < 5)
cannam@85: 	      goto fail;
cannam@85: 
cannam@85: 	    crc = id3_parse_syncsafe(&ehptr, 5);
cannam@85: 	    ehptr += bytes - 5;
cannam@85: 
cannam@85: 	    if (crc != id3_crc_compute(ptr, end - ptr))
cannam@85: 	      goto fail;
cannam@85: 	  }
cannam@85: 
cannam@85: 	  if (tag->extendedflags & ID3_TAG_EXTENDEDFLAG_TAGRESTRICTIONS) {
cannam@85: 	    bytes = id3_parse_uint(&ehptr, 1);
cannam@85: 	    if (bytes < 1)
cannam@85: 	      goto fail;
cannam@85: 
cannam@85: 	    tag->restrictions = id3_parse_uint(&ehptr, 1);
cannam@85: 	    ehptr += bytes - 1;
cannam@85: 	  }
cannam@85: 	}
cannam@85: 	break;
cannam@85:       }
cannam@85:     }
cannam@85: 
cannam@85:     /* frames */
cannam@85: 
cannam@85:     while (ptr < end) {
cannam@85:       struct id3_frame *frame;
cannam@85: 
cannam@85:       if (*ptr == 0)
cannam@85: 	break;  /* padding */
cannam@85: 
cannam@85:       frame = id3_frame_parse(&ptr, end - ptr, tag->version);
cannam@85:       if (frame == 0 || id3_tag_attachframe(tag, frame) == -1)
cannam@85: 	goto fail;
cannam@85:     }
cannam@85: 
cannam@85:     if (ID3_TAG_VERSION_MAJOR(tag->version) < 4 &&
cannam@85: 	id3_compat_fixup(tag) == -1)
cannam@85:       goto fail;
cannam@85:   }
cannam@85: 
cannam@85:   if (0) {
cannam@85:   fail:
cannam@85:     id3_tag_delete(tag);
cannam@85:     tag = 0;
cannam@85:   }
cannam@85: 
cannam@85:   if (mem)
cannam@85:     free(mem);
cannam@85: 
cannam@85:   return tag;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->parse()
cannam@85:  * DESCRIPTION:	parse a complete ID3 tag
cannam@85:  */
cannam@85: struct id3_tag *id3_tag_parse(id3_byte_t const *data, id3_length_t length)
cannam@85: {
cannam@85:   id3_byte_t const *ptr;
cannam@85:   unsigned int version;
cannam@85:   int flags;
cannam@85:   id3_length_t size;
cannam@85: 
cannam@85:   assert(data);
cannam@85: 
cannam@85:   switch (tagtype(data, length)) {
cannam@85:   case TAGTYPE_ID3V1:
cannam@85:     return (length < 128) ? 0 : v1_parse(data);
cannam@85: 
cannam@85:   case TAGTYPE_ID3V2:
cannam@85:     break;
cannam@85: 
cannam@85:   case TAGTYPE_ID3V2_FOOTER:
cannam@85:   case TAGTYPE_NONE:
cannam@85:     return 0;
cannam@85:   }
cannam@85: 
cannam@85:   /* ID3v2.x */
cannam@85: 
cannam@85:   ptr = data;
cannam@85:   parse_header(&ptr, &version, &flags, &size);
cannam@85: 
cannam@85:   switch (ID3_TAG_VERSION_MAJOR(version)) {
cannam@85:   case 4:
cannam@85:     if (flags & ID3_TAG_FLAG_FOOTERPRESENT)
cannam@85:       size += 10;
cannam@85:   case 2:
cannam@85:   case 3:
cannam@85:     return (length < 10 + size) ? 0 : v2_parse(data);
cannam@85:   }
cannam@85: 
cannam@85:   return 0;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: void v1_renderstr(struct id3_tag const *tag, char const *frameid,
cannam@85: 		  id3_byte_t **buffer, id3_length_t length)
cannam@85: {
cannam@85:   struct id3_frame *frame;
cannam@85:   id3_ucs4_t const *string;
cannam@85: 
cannam@85:   frame = id3_tag_findframe(tag, frameid, 0);
cannam@85:   if (frame == 0)
cannam@85:     string = id3_ucs4_empty;
cannam@85:   else {
cannam@85:     if (strcmp(frameid, ID3_FRAME_COMMENT) == 0)
cannam@85:       string = id3_field_getfullstring(&frame->fields[3]);
cannam@85:     else
cannam@85:       string = id3_field_getstrings(&frame->fields[1], 0);
cannam@85:   }
cannam@85: 
cannam@85:   id3_render_paddedstring(buffer, string, length);
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	v1->render()
cannam@85:  * DESCRIPTION:	render an ID3v1 (or ID3v1.1) tag
cannam@85:  */
cannam@85: static
cannam@85: id3_length_t v1_render(struct id3_tag const *tag, id3_byte_t *buffer)
cannam@85: {
cannam@85:   id3_byte_t data[128], *ptr;
cannam@85:   struct id3_frame *frame;
cannam@85:   unsigned int i;
cannam@85:   int genre = -1;
cannam@85: 
cannam@85:   ptr = data;
cannam@85: 
cannam@85:   id3_render_immediate(&ptr, "TAG", 3);
cannam@85: 
cannam@85:   v1_renderstr(tag, ID3_FRAME_TITLE,   &ptr, 30);
cannam@85:   v1_renderstr(tag, ID3_FRAME_ARTIST,  &ptr, 30);
cannam@85:   v1_renderstr(tag, ID3_FRAME_ALBUM,   &ptr, 30);
cannam@85:   v1_renderstr(tag, ID3_FRAME_YEAR,    &ptr,  4);
cannam@85:   v1_renderstr(tag, ID3_FRAME_COMMENT, &ptr, 30);
cannam@85: 
cannam@85:   /* ID3v1.1 track number */
cannam@85: 
cannam@85:   frame = id3_tag_findframe(tag, ID3_FRAME_TRACK, 0);
cannam@85:   if (frame) {
cannam@85:     unsigned int track;
cannam@85: 
cannam@85:     track = id3_ucs4_getnumber(id3_field_getstrings(&frame->fields[1], 0));
cannam@85:     if (track > 0 && track <= 0xff) {
cannam@85:       ptr[-2] = 0;
cannam@85:       ptr[-1] = track;
cannam@85:     }
cannam@85:   }
cannam@85: 
cannam@85:   /* ID3v1 genre number */
cannam@85: 
cannam@85:   frame = id3_tag_findframe(tag, ID3_FRAME_GENRE, 0);
cannam@85:   if (frame) {
cannam@85:     unsigned int nstrings;
cannam@85: 
cannam@85:     nstrings = id3_field_getnstrings(&frame->fields[1]);
cannam@85: 
cannam@85:     for (i = 0; i < nstrings; ++i) {
cannam@85:       genre = id3_genre_number(id3_field_getstrings(&frame->fields[1], i));
cannam@85:       if (genre != -1)
cannam@85: 	break;
cannam@85:     }
cannam@85: 
cannam@85:     if (i == nstrings && nstrings > 0)
cannam@85:       genre = ID3_GENRE_OTHER;
cannam@85:   }
cannam@85: 
cannam@85:   id3_render_int(&ptr, genre, 1);
cannam@85: 
cannam@85:   /* make sure the tag is not empty */
cannam@85: 
cannam@85:   if (genre == -1) {
cannam@85:     for (i = 3; i < 127; ++i) {
cannam@85:       if (data[i] != ' ')
cannam@85: 	break;
cannam@85:     }
cannam@85: 
cannam@85:     if (i == 127)
cannam@85:       return 0;
cannam@85:   }
cannam@85: 
cannam@85:   if (buffer)
cannam@85:     memcpy(buffer, data, 128);
cannam@85: 
cannam@85:   return 128;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	tag->render()
cannam@85:  * DESCRIPTION:	render a complete ID3 tag
cannam@85:  */
cannam@85: id3_length_t id3_tag_render(struct id3_tag const *tag, id3_byte_t *buffer)
cannam@85: {
cannam@85:   id3_length_t size = 0;
cannam@85:   id3_byte_t **ptr,
cannam@85:     *header_ptr = 0, *tagsize_ptr = 0, *crc_ptr = 0, *frames_ptr = 0;
cannam@85:   int flags, extendedflags;
cannam@85:   unsigned int i;
cannam@85: 
cannam@85:   assert(tag);
cannam@85: 
cannam@85:   if (tag->options & ID3_TAG_OPTION_ID3V1)
cannam@85:     return v1_render(tag, buffer);
cannam@85: 
cannam@85:   /* a tag must contain at least one (renderable) frame */
cannam@85: 
cannam@85:   for (i = 0; i < tag->nframes; ++i) {
cannam@85:     if (id3_frame_render(tag->frames[i], 0, 0) > 0)
cannam@85:       break;
cannam@85:   }
cannam@85: 
cannam@85:   if (i == tag->nframes)
cannam@85:     return 0;
cannam@85: 
cannam@85:   ptr = buffer ? &buffer : 0;
cannam@85: 
cannam@85:   /* get flags */
cannam@85: 
cannam@85:   flags         = tag->flags         & ID3_TAG_FLAG_KNOWNFLAGS;
cannam@85:   extendedflags = tag->extendedflags & ID3_TAG_EXTENDEDFLAG_KNOWNFLAGS;
cannam@85: 
cannam@85:   extendedflags &= ~ID3_TAG_EXTENDEDFLAG_CRCDATAPRESENT;
cannam@85:   if (tag->options & ID3_TAG_OPTION_CRC)
cannam@85:     extendedflags |= ID3_TAG_EXTENDEDFLAG_CRCDATAPRESENT;
cannam@85: 
cannam@85:   extendedflags &= ~ID3_TAG_EXTENDEDFLAG_TAGRESTRICTIONS;
cannam@85:   if (tag->restrictions)
cannam@85:     extendedflags |= ID3_TAG_EXTENDEDFLAG_TAGRESTRICTIONS;
cannam@85: 
cannam@85:   flags &= ~ID3_TAG_FLAG_UNSYNCHRONISATION;
cannam@85:   if (tag->options & ID3_TAG_OPTION_UNSYNCHRONISATION)
cannam@85:     flags |= ID3_TAG_FLAG_UNSYNCHRONISATION;
cannam@85: 
cannam@85:   flags &= ~ID3_TAG_FLAG_EXTENDEDHEADER;
cannam@85:   if (extendedflags)
cannam@85:     flags |= ID3_TAG_FLAG_EXTENDEDHEADER;
cannam@85: 
cannam@85:   flags &= ~ID3_TAG_FLAG_FOOTERPRESENT;
cannam@85:   if (tag->options & ID3_TAG_OPTION_APPENDEDTAG)
cannam@85:     flags |= ID3_TAG_FLAG_FOOTERPRESENT;
cannam@85: 
cannam@85:   /* header */
cannam@85: 
cannam@85:   if (ptr)
cannam@85:     header_ptr = *ptr;
cannam@85: 
cannam@85:   size += id3_render_immediate(ptr, "ID3", 3);
cannam@85:   size += id3_render_int(ptr, ID3_TAG_VERSION, 2);
cannam@85:   size += id3_render_int(ptr, flags, 1);
cannam@85: 
cannam@85:   if (ptr)
cannam@85:     tagsize_ptr = *ptr;
cannam@85: 
cannam@85:   size += id3_render_syncsafe(ptr, 0, 4);
cannam@85: 
cannam@85:   /* extended header */
cannam@85: 
cannam@85:   if (flags & ID3_TAG_FLAG_EXTENDEDHEADER) {
cannam@85:     id3_length_t ehsize = 0;
cannam@85:     id3_byte_t *ehsize_ptr = 0;
cannam@85: 
cannam@85:     if (ptr)
cannam@85:       ehsize_ptr = *ptr;
cannam@85: 
cannam@85:     ehsize += id3_render_syncsafe(ptr, 0, 4);
cannam@85:     ehsize += id3_render_int(ptr, 1, 1);
cannam@85:     ehsize += id3_render_int(ptr, extendedflags, 1);
cannam@85: 
cannam@85:     if (extendedflags & ID3_TAG_EXTENDEDFLAG_TAGISANUPDATE)
cannam@85:       ehsize += id3_render_int(ptr, 0, 1);
cannam@85: 
cannam@85:     if (extendedflags & ID3_TAG_EXTENDEDFLAG_CRCDATAPRESENT) {
cannam@85:       ehsize += id3_render_int(ptr, 5, 1);
cannam@85: 
cannam@85:       if (ptr)
cannam@85: 	crc_ptr = *ptr;
cannam@85: 
cannam@85:       ehsize += id3_render_syncsafe(ptr, 0, 5);
cannam@85:     }
cannam@85: 
cannam@85:     if (extendedflags & ID3_TAG_EXTENDEDFLAG_TAGRESTRICTIONS) {
cannam@85:       ehsize += id3_render_int(ptr, 1, 1);
cannam@85:       ehsize += id3_render_int(ptr, tag->restrictions, 1);
cannam@85:     }
cannam@85: 
cannam@85:     if (ehsize_ptr)
cannam@85:       id3_render_syncsafe(&ehsize_ptr, ehsize, 4);
cannam@85: 
cannam@85:     size += ehsize;
cannam@85:   }
cannam@85: 
cannam@85:   /* frames */
cannam@85: 
cannam@85:   if (ptr)
cannam@85:     frames_ptr = *ptr;
cannam@85: 
cannam@85:   for (i = 0; i < tag->nframes; ++i)
cannam@85:     size += id3_frame_render(tag->frames[i], ptr, tag->options);
cannam@85: 
cannam@85:   /* padding */
cannam@85: 
cannam@85:   if (!(flags & ID3_TAG_FLAG_FOOTERPRESENT)) {
cannam@85:     if (size < tag->paddedsize)
cannam@85:       size += id3_render_padding(ptr, 0, tag->paddedsize - size);
cannam@85:     else if (tag->options & ID3_TAG_OPTION_UNSYNCHRONISATION) {
cannam@85:       if (ptr == 0)
cannam@85: 	size += 1;
cannam@85:       else {
cannam@85: 	if ((*ptr)[-1] == 0xff)
cannam@85: 	  size += id3_render_padding(ptr, 0, 1);
cannam@85:       }
cannam@85:     }
cannam@85:   }
cannam@85: 
cannam@85:   /* patch tag size and CRC */
cannam@85: 
cannam@85:   if (tagsize_ptr)
cannam@85:     id3_render_syncsafe(&tagsize_ptr, size - 10, 4);
cannam@85: 
cannam@85:   if (crc_ptr) {
cannam@85:     id3_render_syncsafe(&crc_ptr,
cannam@85: 			id3_crc_compute(frames_ptr, *ptr - frames_ptr), 5);
cannam@85:   }
cannam@85: 
cannam@85:   /* footer */
cannam@85: 
cannam@85:   if (flags & ID3_TAG_FLAG_FOOTERPRESENT) {
cannam@85:     size += id3_render_immediate(ptr, "3DI", 3);
cannam@85:     size += id3_render_binary(ptr, header_ptr + 3, 7);
cannam@85:   }
cannam@85: 
cannam@85:   return size;
cannam@85: }