src/libFLAC/ogg_helper.c

   1 /* libFLAC - Free Lossless Audio Codec
   2  * Copyright (C) 2004,2005,2006,2007  Josh Coalson
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * - Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *
  11  * - Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
  14  *
  15  * - Neither the name of the Xiph.org Foundation nor the names of its
  16  * contributors may be used to endorse or promote products derived from
  17  * this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
  23  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  24  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  26  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  27  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  28  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  29  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #if HAVE_CONFIG_H
  33 #  include <config.h>
  34 #endif
  35
  36 #include <stdlib.h> /* for malloc() */
  37 #include <string.h> /* for memcmp(), memcpy() */
  38 #include "FLAC/assert.h"
  39 #include "private/ogg_helper.h"
  40 #include "protected/stream_encoder.h"
  41
  42
  43 static FLAC__bool full_read_(FLAC__StreamEncoder *encoder, FLAC__byte *buffer, size_t bytes, FLAC__StreamEncoderReadCallback read_callback, void *client_data)
  44 {
  45         while(bytes > 0) {
  46                 size_t bytes_read = bytes;
  47                 switch(read_callback(encoder, buffer, &bytes_read, client_data)) {
  48                         case FLAC__STREAM_ENCODER_READ_STATUS_CONTINUE:
  49                                 bytes -= bytes_read;
  50                                 buffer += bytes_read;
  51                                 break;
  52                         case FLAC__STREAM_ENCODER_READ_STATUS_END_OF_STREAM:
  53                                 if(bytes_read == 0) {
  54                                         encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR;
  55                                         return false;
  56                                 }
  57                                 bytes -= bytes_read;
  58                                 buffer += bytes_read;
  59                                 break;
  60                         case FLAC__STREAM_ENCODER_READ_STATUS_ABORT:
  61                                 encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
  62                                 return false;
  63                         case FLAC__STREAM_ENCODER_READ_STATUS_UNSUPPORTED:
  64                                 return false;
  65                         default:
  66                                 /* double protection: */
  67                                 FLAC__ASSERT(0);
  68                                 encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
  69                                 return false;
  70                 }
  71         }
  72
  73         return true;
  74 }
  75
  76 void simple_ogg_page__init(ogg_page *page)
  77 {
  78         page->header = 0;
  79         page->header_len = 0;
  80         page->body = 0;
  81         page->body_len = 0;
  82 }
  83
  84 void simple_ogg_page__clear(ogg_page *page)
  85 {
  86         if(page->header)
  87                 free(page->header);
  88         if(page->body)
  89                 free(page->body);
  90         simple_ogg_page__init(page);
  91 }
  92
  93 FLAC__bool simple_ogg_page__get_at(FLAC__StreamEncoder *encoder, FLAC__uint64 position, ogg_page *page, FLAC__StreamEncoderSeekCallback seek_callback, FLAC__StreamEncoderReadCallback read_callback, void *client_data)
  94 {
  95         static const unsigned OGG_HEADER_FIXED_PORTION_LEN = 27;
  96         static const unsigned OGG_MAX_HEADER_LEN = 27/*OGG_HEADER_FIXED_PORTION_LEN*/ + 255;
  97         FLAC__byte crc[4];
  98         FLAC__StreamEncoderSeekStatus seek_status;
  99
 100         FLAC__ASSERT(page->header == 0);
 101         FLAC__ASSERT(page->header_len == 0);
 102         FLAC__ASSERT(page->body == 0);
 103         FLAC__ASSERT(page->body_len == 0);
 104
 105         /* move the stream pointer to the supposed beginning of the page */
 106         if(0 == seek_callback)
 107                 return false;
 108         if((seek_status = seek_callback((FLAC__StreamEncoder*)encoder, position, client_data)) != FLAC__STREAM_ENCODER_SEEK_STATUS_OK) {
 109                 if(seek_status == FLAC__STREAM_ENCODER_SEEK_STATUS_ERROR)
 110                         encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
 111                 return false;
 112         }
 113
 114         /* allocate space for the page header */
 115         if(0 == (page->header = (unsigned char *)malloc(OGG_MAX_HEADER_LEN))) {
 116                 encoder->protected_->state = FLAC__STREAM_ENCODER_MEMORY_ALLOCATION_ERROR;
 117                 return false;
 118         }
 119
 120         /* read in the fixed part of the page header (up to but not including
 121          * the segment table */
 122         if(!full_read_(encoder, page->header, OGG_HEADER_FIXED_PORTION_LEN, read_callback, client_data))
 123                 return false;
 124
 125         page->header_len = OGG_HEADER_FIXED_PORTION_LEN + page->header[26];
 126
 127         /* check to see if it's a correct, "simple" page (one packet only) */
 128         if(
 129                 memcmp(page->header, "OggS", 4) ||               /* doesn't start with OggS */
 130                 (page->header[5] & 0x01) ||                      /* continued packet */
 131                 memcmp(page->header+6, "\0\0\0\0\0\0\0\0", 8) || /* granulepos is non-zero */
 132                 page->header[26] == 0                            /* packet is 0-size */
 133         ) {
 134                 encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR;
 135                 return false;
 136         }
 137
 138         /* read in the segment table */
 139         if(!full_read_(encoder, page->header + OGG_HEADER_FIXED_PORTION_LEN, page->header[26], read_callback, client_data))
 140                 return false;
 141
 142         {
 143                 unsigned i;
 144
 145                 /* check to see that it specifies a single packet */
 146                 for(i = 0; i < (unsigned)page->header[26] - 1; i++) {
 147                         if(page->header[i + OGG_HEADER_FIXED_PORTION_LEN] != 255) {
 148                                 encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR;
 149                                 return false;
 150                         }
 151                 }
 152
 153                 page->body_len = 255 * i + page->header[i + OGG_HEADER_FIXED_PORTION_LEN];
 154         }
 155
 156         /* allocate space for the page body */
 157         if(0 == (page->body = (unsigned char *)malloc(page->body_len))) {
 158                 encoder->protected_->state = FLAC__STREAM_ENCODER_MEMORY_ALLOCATION_ERROR;
 159                 return false;
 160         }
 161
 162         /* read in the page body */
 163         if(!full_read_(encoder, page->body, page->body_len, read_callback, client_data))
 164                 return false;
 165
 166         /* check the CRC */
 167         memcpy(crc, page->header+22, 4);
 168         ogg_page_checksum_set(page);
 169         if(memcmp(crc, page->header+22, 4)) {
 170                 encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR;
 171                 return false;
 172         }
 173
 174         return true;
 175 }
 176
 177 FLAC__bool simple_ogg_page__set_at(FLAC__StreamEncoder *encoder, FLAC__uint64 position, ogg_page *page, FLAC__StreamEncoderSeekCallback seek_callback, FLAC__StreamEncoderWriteCallback write_callback, void *client_data)
 178 {
 179         FLAC__StreamEncoderSeekStatus seek_status;
 180
 181         FLAC__ASSERT(page->header != 0);
 182         FLAC__ASSERT(page->header_len != 0);
 183         FLAC__ASSERT(page->body != 0);
 184         FLAC__ASSERT(page->body_len != 0);
 185
 186         /* move the stream pointer to the supposed beginning of the page */
 187         if(0 == seek_callback)
 188                 return false;
 189         if((seek_status = seek_callback((FLAC__StreamEncoder*)encoder, position, client_data)) != FLAC__STREAM_ENCODER_SEEK_STATUS_OK) {
 190                 if(seek_status == FLAC__STREAM_ENCODER_SEEK_STATUS_ERROR)
 191                         encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
 192                 return false;
 193         }
 194
 195         ogg_page_checksum_set(page);
 196
 197         /* re-write the page */
 198         if(write_callback((FLAC__StreamEncoder*)encoder, page->header, page->header_len, 0, 0, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
 199                 encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
 200                 return false;
 201         }
 202         if(write_callback((FLAC__StreamEncoder*)encoder, page->body, page->body_len, 0, 0, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
 203                 encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
 204                 return false;
 205         }
 206
 207         return true;
 208 }