FLAC/src/ogg_helper.c

   1 /* libFLAC - Free Lossless Audio Codec
   2  * Copyright (C) 2004-2009  Josh Coalson
   3  * Copyright (C) 2011-2016  Xiph.Org Foundation
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  * notice, this list of conditions and the following disclaimer.
  11  *
  12  * - Redistributions in binary form must reproduce the above copyright
  13  * notice, this list of conditions and the following disclaimer in the
  14  * documentation and/or other materials provided with the distribution.
  15  *
  16  * - Neither the name of the Xiph.org Foundation nor the names of its
  17  * contributors may be used to endorse or promote products derived from
  18  * this software without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  23  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
  24  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  26  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  27  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  28  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  29  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  30  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #ifdef HAVE_CONFIG_H
  34 #  include <config.h>
  35 #endif
  36
  37 #include <stdlib.h> /* for malloc() */
  38 #include <string.h> /* for memcmp(), memcpy() */
  39 #include "FLAC/assert.h"
  40 #include "share/alloc.h"
  41 #include "private/ogg_helper.h"
  42 #include "protected/stream_encoder.h"
  43
  44
  45 static FLAC__bool full_read_(FLAC__StreamEncoder *encoder, FLAC__byte *buffer, size_t bytes, FLAC__StreamEncoderReadCallback read_callback, void *client_data)
  46 {
  47         while(bytes > 0) {
  48                 size_t bytes_read = bytes;
  49                 switch(read_callback(encoder, buffer, &bytes_read, client_data)) {
  50                         case FLAC__STREAM_ENCODER_READ_STATUS_CONTINUE:
  51                                 bytes -= bytes_read;
  52                                 buffer += bytes_read;
  53                                 break;
  54                         case FLAC__STREAM_ENCODER_READ_STATUS_END_OF_STREAM:
  55                                 if(bytes_read == 0) {
  56                                         encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR;
  57                                         return false;
  58                                 }
  59                                 bytes -= bytes_read;
  60                                 buffer += bytes_read;
  61                                 break;
  62                         case FLAC__STREAM_ENCODER_READ_STATUS_ABORT:
  63                                 encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
  64                                 return false;
  65                         case FLAC__STREAM_ENCODER_READ_STATUS_UNSUPPORTED:
  66                                 return false;
  67                         default:
  68                                 /* double protection: */
  69                                 FLAC__ASSERT(0);
  70                                 encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
  71                                 return false;
  72                 }
  73         }
  74
  75         return true;
  76 }
  77
  78 void simple_ogg_page__init(ogg_page *page)
  79 {
  80         page->header = 0;
  81         page->header_len = 0;
  82         page->body = 0;
  83         page->body_len = 0;
  84 }
  85
  86 void simple_ogg_page__clear(ogg_page *page)
  87 {
  88         if(page->header)
  89                 free(page->header);
  90         if(page->body)
  91                 free(page->body);
  92         simple_ogg_page__init(page);
  93 }
  94
  95 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)
  96 {
  97         static const unsigned OGG_HEADER_FIXED_PORTION_LEN = 27;
  98         static const unsigned OGG_MAX_HEADER_LEN = 27/*OGG_HEADER_FIXED_PORTION_LEN*/ + 255;
  99         FLAC__byte crc[4];
 100         FLAC__StreamEncoderSeekStatus seek_status;
 101
 102         FLAC__ASSERT(page->header == 0);
 103         FLAC__ASSERT(page->header_len == 0);
 104         FLAC__ASSERT(page->body == 0);
 105         FLAC__ASSERT(page->body_len == 0);
 106
 107         /* move the stream pointer to the supposed beginning of the page */
 108         if(0 == seek_callback)
 109                 return false;
 110         if((seek_status = seek_callback((FLAC__StreamEncoder*)encoder, position, client_data)) != FLAC__STREAM_ENCODER_SEEK_STATUS_OK) {
 111                 if(seek_status == FLAC__STREAM_ENCODER_SEEK_STATUS_ERROR)
 112                         encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
 113                 return false;
 114         }
 115
 116         /* allocate space for the page header */
 117         if(0 == (page->header = safe_malloc_(OGG_MAX_HEADER_LEN))) {
 118                 encoder->protected_->state = FLAC__STREAM_ENCODER_MEMORY_ALLOCATION_ERROR;
 119                 return false;
 120         }
 121
 122         /* read in the fixed part of the page header (up to but not including
 123          * the segment table */
 124         if(!full_read_(encoder, page->header, OGG_HEADER_FIXED_PORTION_LEN, read_callback, client_data))
 125                 return false;
 126
 127         page->header_len = OGG_HEADER_FIXED_PORTION_LEN + page->header[26];
 128
 129         /* check to see if it's a correct, "simple" page (one packet only) */
 130         if(
 131                 memcmp(page->header, "OggS", 4) ||               /* doesn't start with OggS */
 132                 (page->header[5] & 0x01) ||                      /* continued packet */
 133                 memcmp(page->header+6, "\0\0\0\0\0\0\0\0", 8) || /* granulepos is non-zero */
 134                 page->header[26] == 0                            /* packet is 0-size */
 135         ) {
 136                 encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR;
 137                 return false;
 138         }
 139
 140         /* read in the segment table */
 141         if(!full_read_(encoder, page->header + OGG_HEADER_FIXED_PORTION_LEN, page->header[26], read_callback, client_data))
 142                 return false;
 143
 144         {
 145                 unsigned i;
 146
 147                 /* check to see that it specifies a single packet */
 148                 for(i = 0; i < (unsigned)page->header[26] - 1; i++) {
 149                         if(page->header[i + OGG_HEADER_FIXED_PORTION_LEN] != 255) {
 150                                 encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR;
 151                                 return false;
 152                         }
 153                 }
 154
 155                 page->body_len = 255 * i + page->header[i + OGG_HEADER_FIXED_PORTION_LEN];
 156         }
 157
 158         /* allocate space for the page body */
 159         if(0 == (page->body = safe_malloc_(page->body_len))) {
 160                 encoder->protected_->state = FLAC__STREAM_ENCODER_MEMORY_ALLOCATION_ERROR;
 161                 return false;
 162         }
 163
 164         /* read in the page body */
 165         if(!full_read_(encoder, page->body, page->body_len, read_callback, client_data))
 166                 return false;
 167
 168         /* check the CRC */
 169         memcpy(crc, page->header+22, 4);
 170         ogg_page_checksum_set(page);
 171         if(memcmp(crc, page->header+22, 4)) {
 172                 encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR;
 173                 return false;
 174         }
 175
 176         return true;
 177 }
 178
 179 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)
 180 {
 181         FLAC__StreamEncoderSeekStatus seek_status;
 182
 183         FLAC__ASSERT(page->header != 0);
 184         FLAC__ASSERT(page->header_len != 0);
 185         FLAC__ASSERT(page->body != 0);
 186         FLAC__ASSERT(page->body_len != 0);
 187
 188         /* move the stream pointer to the supposed beginning of the page */
 189         if(0 == seek_callback)
 190                 return false;
 191         if((seek_status = seek_callback((FLAC__StreamEncoder*)encoder, position, client_data)) != FLAC__STREAM_ENCODER_SEEK_STATUS_OK) {
 192                 if(seek_status == FLAC__STREAM_ENCODER_SEEK_STATUS_ERROR)
 193                         encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
 194                 return false;
 195         }
 196
 197         ogg_page_checksum_set(page);
 198
 199         /* re-write the page */
 200         if(write_callback((FLAC__StreamEncoder*)encoder, page->header, page->header_len, 0, 0, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
 201                 encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
 202                 return false;
 203         }
 204         if(write_callback((FLAC__StreamEncoder*)encoder, page->body, page->body_len, 0, 0, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) {
 205                 encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR;
 206                 return false;
 207         }
 208
 209         return true;
 210 }