ref: 86c9aebfb42aa5909ae2eed6b438f16411909789
dir: /common/id3lib/src/frame_parse.cpp/
// $Id: frame_parse.cpp,v 1.1 2002/01/21 08:16:22 menno Exp $ // id3lib: a C++ library for creating and manipulating id3v1/v2 tags // Copyright 1999, 2000 Scott Thomas Haug // This library is free software; you can redistribute it and/or modify it // under the terms of the GNU Library General Public License as published by // the Free Software Foundation; either version 2 of the License, or (at your // option) any later version. // // This library is distributed in the hope that it will be useful, but WITHOUT // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or // FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public // License for more details. // // You should have received a copy of the GNU Library General Public License // along with this library; if not, write to the Free Software Foundation, // Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. // The id3lib authors encourage improvements and optimisations to be sent to // the id3lib coordinator. Please see the README file for details on where to // send such submissions. See the AUTHORS file for a list of people who have // contributed to id3lib. See the ChangeLog file for a list of changes to // id3lib. These files are distributed with id3lib at // http://download.sourceforge.net/id3lib/ #include <zlib.h> #include "frame.h" #include "utils.h" #if defined HAVE_CONFIG_H #include <config.h> #endif size_t ID3_Frame::Parse(const uchar * const buffer, size_t size) { __bad_parse = false; const size_t hdr_size = __hdr.Parse(buffer, size); if (!hdr_size) { return 0; } // data is the part of the frame buffer that appears after the header const uchar* data = &buffer[hdr_size]; const size_t data_size = __hdr.GetDataSize(); size_t extras = 0; // how many bytes remain to be parsed size_t remainder = data_size - MIN(extras, data_size); unsigned long expanded_size = 0; if (__hdr.GetCompression()) { expanded_size = ParseNumber(&data[extras]); extras += sizeof(uint32); } if (__hdr.GetEncryption()) { this->_SetEncryptionID(data[extras++]); } if (__hdr.GetGrouping()) { this->_SetGroupingID(data[extras++]); } data += extras; // expand out the data if it's compressed uchar* expanded_data = NULL; if (__hdr.GetCompression()) { expanded_data = new uchar[expanded_size]; uncompress(expanded_data, &expanded_size, data, remainder); data = expanded_data; remainder = expanded_size; } // set the type of frame based on the parsed header this->_ClearFields(); this->_InitFields(); try { ID3_TextEnc enc = ID3TE_ASCII; // set the default encoding ID3_V2Spec spec = this->GetSpec(); // parse the frame's fields for (ID3_Field** fi = __fields; fi != __fields + __num_fields; fi++) { if (!*fi) { // Ack! Why is the field NULL? Log this... continue; } if (remainder == 0) { // there's no remaining data to parse! __bad_parse = true; break; } if (!(*fi)->InScope(spec)) { // this field isn't in scope, so don't attempt to parse into it // rather, give it some reasonable default value in case someone tries // to access it switch ((*fi)->GetType()) { case ID3FTY_INTEGER: **fi = (uint32) 0; break; default: **fi = ""; break; } // now continue with the rest of the fields continue; } (*fi)->SetEncoding(enc); size_t frame_size = (*fi)->Parse(data, remainder); if (0 == frame_size) { // nothing to parse! ack! parse error... __bad_parse = true; break; } if ((*fi)->GetID() == ID3FN_TEXTENC) { enc = static_cast<ID3_TextEnc>((*fi)->Get()); } data += frame_size; remainder -= MIN(frame_size, remainder); } } catch (...) { // TODO: log this! //cerr << "*** parsing error!" << endl; // There's been an error in the parsing of the frame. __bad_parse = true; } __changed = false; delete [] expanded_data; return MIN(hdr_size + data_size, size); }