/* libOggFLAC - Free Lossless Audio Codec + Ogg library * Copyright (C) 2004 Josh Coalson * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of the Xiph.org Foundation nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include /* for malloc() */ #include /* for memcmp(), memcpy() */ #include "FLAC/assert.h" #include "private/ogg_helper.h" #include "protected/seekable_stream_encoder.h" static FLAC__bool full_read_(OggFLAC__SeekableStreamEncoder *encoder, FLAC__byte *buffer, unsigned bytes, OggFLAC__SeekableStreamEncoderReadCallback read_callback, void *client_data) { while(bytes > 0) { unsigned bytes_read = bytes; switch(read_callback(encoder, buffer, &bytes_read, client_data)) { case OggFLAC__SEEKABLE_STREAM_ENCODER_READ_STATUS_CONTINUE: bytes -= bytes_read; buffer += bytes_read; break; case OggFLAC__SEEKABLE_STREAM_ENCODER_READ_STATUS_END_OF_STREAM: if(bytes_read == 0) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_OGG_ERROR; return false; } bytes -= bytes_read; buffer += bytes_read; break; case OggFLAC__SEEKABLE_STREAM_ENCODER_READ_STATUS_ABORT: encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_READ_ERROR; return false; default: /* double protection: */ FLAC__ASSERT(0); encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_READ_ERROR; return false; } } return true; } void simple_ogg_page__init(ogg_page *page) { page->header = 0; page->header_len = 0; page->body = 0; page->body_len = 0; } void simple_ogg_page__clear(ogg_page *page) { if(page->header) free(page->header); if(page->body) free(page->body); simple_ogg_page__init(page); } FLAC__bool simple_ogg_page__get_at(OggFLAC__SeekableStreamEncoder *encoder, FLAC__uint64 position, ogg_page *page, OggFLAC__SeekableStreamEncoderSeekCallback seek_callback, OggFLAC__SeekableStreamEncoderReadCallback read_callback, void *client_data) { static const unsigned OGG_HEADER_FIXED_PORTION_LEN = 27; static const unsigned OGG_MAX_HEADER_LEN = 27/*OGG_HEADER_FIXED_PORTION_LEN*/ + 255; FLAC__byte crc[4]; FLAC__ASSERT(page->header == 0); FLAC__ASSERT(page->header_len == 0); FLAC__ASSERT(page->body == 0); FLAC__ASSERT(page->body_len == 0); /* move the stream pointer to the supposed beginning of the page */ if(seek_callback(encoder, position, client_data) != FLAC__SEEKABLE_STREAM_ENCODER_SEEK_STATUS_OK) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_SEEK_ERROR; return false; } /* allocate space for the page header */ if(0 == (page->header = malloc(OGG_MAX_HEADER_LEN))) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_MEMORY_ALLOCATION_ERROR; return false; } /* read in the fixed part of the page header (up to but not including * the segment table */ if(!full_read_(encoder, page->header, OGG_HEADER_FIXED_PORTION_LEN, read_callback, client_data)) return false; page->header_len = OGG_HEADER_FIXED_PORTION_LEN + page->header[26]; /* check to see if it's a correct, "simple" page (one packet only) */ if( memcmp(page->header, "OggS", 4) || /* doesn't start with OggS */ (page->header[5] & 0x01) || /* continued packet */ memcmp(page->header+6, "\0\0\0\0\0\0\0\0", 8) || /* granulepos is non-zero */ page->header[26] == 0 /* packet is 0-size */ ) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_OGG_ERROR; return false; } /* read in the segment table */ if(!full_read_(encoder, page->header + OGG_HEADER_FIXED_PORTION_LEN, page->header[26], read_callback, client_data)) return false; { unsigned i; /* check to see that it specifies a single packet */ for(i = 0; i < (unsigned)page->header[26] - 1; i++) { if(page->header[i + OGG_HEADER_FIXED_PORTION_LEN] != 255) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_OGG_ERROR; return false; } } page->body_len = 255 * i + page->header[i]; } /* allocate space for the page body */ if(0 == (page->body = malloc(page->body_len))) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_MEMORY_ALLOCATION_ERROR; return false; } /* read in the page body */ if(!full_read_(encoder, page->body, page->body_len, read_callback, client_data)) return false; /* check the CRC */ memcpy(crc, page->header+22, 4); ogg_page_checksum_set(page); if(memcmp(crc, page->header+22, 4)) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_OGG_ERROR; return false; } return true; } FLAC__bool simple_ogg_page__set_at(OggFLAC__SeekableStreamEncoder *encoder, FLAC__uint64 position, ogg_page *page, OggFLAC__SeekableStreamEncoderSeekCallback seek_callback, OggFLAC__SeekableStreamEncoderWriteCallback write_callback, void *client_data) { FLAC__ASSERT(page->header != 0); FLAC__ASSERT(page->header_len != 0); FLAC__ASSERT(page->body != 0); FLAC__ASSERT(page->body_len != 0); /* move the stream pointer to the supposed beginning of the page */ if(seek_callback(encoder, position, client_data) != FLAC__SEEKABLE_STREAM_ENCODER_SEEK_STATUS_OK) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_SEEK_ERROR; return false; } ogg_page_checksum_set(page); /* re-write the page */ if(write_callback(encoder, page->header, page->header_len, 0, 0, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) { encoder->protected_->state = OggFLAC__SEEKABLE_STREAM_ENCODER_WRITE_ERROR; return false; } return true; }