diff options
Diffstat (limited to 'libFLAC/ogg_helper.c')
| -rw-r--r-- | libFLAC/ogg_helper.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/libFLAC/ogg_helper.c b/libFLAC/ogg_helper.c new file mode 100644 index 0000000..73f9f0b --- /dev/null +++ b/libFLAC/ogg_helper.c @@ -0,0 +1,209 @@ +/* libFLAC - Free Lossless Audio Codec + * Copyright (C) 2004,2005,2006,2007 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. + */ + +#if HAVE_CONFIG_H +# include <config.h> +#endif + +#include <stdlib.h> /* for malloc() */ +#include <string.h> /* for memcmp(), memcpy() */ +#include "FLAC/assert.h" +#include "share/alloc.h" +#include "private/ogg_helper.h" +#include "protected/stream_encoder.h" + + +static FLAC__bool full_read_(FLAC__StreamEncoder *encoder, FLAC__byte *buffer, size_t bytes, FLAC__StreamEncoderReadCallback read_callback, void *client_data) +{ + while(bytes > 0) { + size_t bytes_read = bytes; + switch(read_callback(encoder, buffer, &bytes_read, client_data)) { + case FLAC__STREAM_ENCODER_READ_STATUS_CONTINUE: + bytes -= bytes_read; + buffer += bytes_read; + break; + case FLAC__STREAM_ENCODER_READ_STATUS_END_OF_STREAM: + if(bytes_read == 0) { + encoder->protected_->state = FLAC__STREAM_ENCODER_OGG_ERROR; + return false; + } + bytes -= bytes_read; + buffer += bytes_read; + break; + case FLAC__STREAM_ENCODER_READ_STATUS_ABORT: + encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR; + return false; + case FLAC__STREAM_ENCODER_READ_STATUS_UNSUPPORTED: + return false; + default: + /* double protection: */ + FLAC__ASSERT(0); + encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_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(FLAC__StreamEncoder *encoder, FLAC__uint64 position, ogg_page *page, FLAC__StreamEncoderSeekCallback seek_callback, FLAC__StreamEncoderReadCallback 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__StreamEncoderSeekStatus seek_status; + + 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(0 == seek_callback) + return false; + if((seek_status = seek_callback((FLAC__StreamEncoder*)encoder, position, client_data)) != FLAC__STREAM_ENCODER_SEEK_STATUS_OK) { + if(seek_status == FLAC__STREAM_ENCODER_SEEK_STATUS_ERROR) + encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR; + return false; + } + + /* allocate space for the page header */ + if(0 == (page->header = (unsigned char *)safe_malloc_(OGG_MAX_HEADER_LEN))) { + encoder->protected_->state = FLAC__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 = FLAC__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 = FLAC__STREAM_ENCODER_OGG_ERROR; + return false; + } + } + + page->body_len = 255 * i + page->header[i + OGG_HEADER_FIXED_PORTION_LEN]; + } + + /* allocate space for the page body */ + if(0 == (page->body = (unsigned char *)safe_malloc_(page->body_len))) { + encoder->protected_->state = FLAC__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 = FLAC__STREAM_ENCODER_OGG_ERROR; + return false; + } + + return true; +} + +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) +{ + FLAC__StreamEncoderSeekStatus seek_status; + + 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(0 == seek_callback) + return false; + if((seek_status = seek_callback((FLAC__StreamEncoder*)encoder, position, client_data)) != FLAC__STREAM_ENCODER_SEEK_STATUS_OK) { + if(seek_status == FLAC__STREAM_ENCODER_SEEK_STATUS_ERROR) + encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR; + return false; + } + + ogg_page_checksum_set(page); + + /* re-write the page */ + if(write_callback((FLAC__StreamEncoder*)encoder, page->header, page->header_len, 0, 0, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) { + encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR; + return false; + } + if(write_callback((FLAC__StreamEncoder*)encoder, page->body, page->body_len, 0, 0, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK) { + encoder->protected_->state = FLAC__STREAM_ENCODER_CLIENT_ERROR; + return false; + } + + return true; +} |