text: //===========================================================================
  //Copyright (C) 2003, 2004 Zentaro Kavanagh
  //
  //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 Zentaro Kavanagh nor the names of 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 ORGANISATION 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 "oggstdafx.h"
  #include <OggPage.h>
  //LEACK CHECKED::: 20041018 - OK.
  
  
  // Checksum tables from libogg
  static unsigned long crc_lookup[256]={
    0x00000000,0x04c11db7,0x09823b6e,0x0d4326d9,
    0x130476dc,0x17c56b6b,0x1a864db2,0x1e475005,
    0x2608edb8,0x22c9f00f,0x2f8ad6d6,0x2b4bcb61,
    0x350c9b64,0x31cd86d3,0x3c8ea00a,0x384fbdbd,
    0x4c11db70,0x48d0c6c7,0x4593e01e,0x4152fda9,
    0x5f15adac,0x5bd4b01b,0x569796c2,0x52568b75,
    0x6a1936c8,0x6ed82b7f,0x639b0da6,0x675a1011,
    0x791d4014,0x7ddc5da3,0x709f7b7a,0x745e66cd,
    0x9823b6e0,0x9ce2ab57,0x91a18d8e,0x95609039,
    0x8b27c03c,0x8fe6dd8b,0x82a5fb52,0x8664e6e5,
    0xbe2b5b58,0xbaea46ef,0xb7a96036,0xb3687d81,
    0xad2f2d84,0xa9ee3033,0xa4ad16ea,0xa06c0b5d,
    0xd4326d90,0xd0f37027,0xddb056fe,0xd9714b49,
    0xc7361b4c,0xc3f706fb,0xceb42022,0xca753d95,
    0xf23a8028,0xf6fb9d9f,0xfbb8bb46,0xff79a6f1,
    0xe13ef6f4,0xe5ffeb43,0xe8bccd9a,0xec7dd02d,
    0x34867077,0x30476dc0,0x3d044b19,0x39c556ae,
    0x278206ab,0x23431b1c,0x2e003dc5,0x2ac12072,
    0x128e9dcf,0x164f8078,0x1b0ca6a1,0x1fcdbb16,
    0x018aeb13,0x054bf6a4,0x0808d07d,0x0cc9cdca,
    0x7897ab07,0x7c56b6b0,0x71159069,0x75d48dde,
    0x6b93dddb,0x6f52c06c,0x6211e6b5,0x66d0fb02,
    0x5e9f46bf,0x5a5e5b08,0x571d7dd1,0x53dc6066,
    0x4d9b3063,0x495a2dd4,0x44190b0d,0x40d816ba,
    0xaca5c697,0xa864db20,0xa527fdf9,0xa1e6e04e,
    0xbfa1b04b,0xbb60adfc,0xb6238b25,0xb2e29692,
    0x8aad2b2f,0x8e6c3698,0x832f1041,0x87ee0df6,
    0x99a95df3,0x9d684044,0x902b669d,0x94ea7b2a,
    0xe0b41de7,0xe4750050,0xe9362689,0xedf73b3e,
    0xf3b06b3b,0xf771768c,0xfa325055,0xfef34de2,
    0xc6bcf05f,0xc27dede8,0xcf3ecb31,0xcbffd686,
    0xd5b88683,0xd1799b34,0xdc3abded,0xd8fba05a,
    0x690ce0ee,0x6dcdfd59,0x608edb80,0x644fc637,
    0x7a089632,0x7ec98b85,0x738aad5c,0x774bb0eb,
    0x4f040d56,0x4bc510e1,0x46863638,0x42472b8f,
    0x5c007b8a,0x58c1663d,0x558240e4,0x51435d53,
    0x251d3b9e,0x21dc2629,0x2c9f00f0,0x285e1d47,
    0x36194d42,0x32d850f5,0x3f9b762c,0x3b5a6b9b,
    0x0315d626,0x07d4cb91,0x0a97ed48,0x0e56f0ff,
    0x1011a0fa,0x14d0bd4d,0x19939b94,0x1d528623,
    0xf12f560e,0xf5ee4bb9,0xf8ad6d60,0xfc6c70d7,
    0xe22b20d2,0xe6ea3d65,0xeba91bbc,0xef68060b,
    0xd727bbb6,0xd3e6a601,0xdea580d8,0xda649d6f,
    0xc423cd6a,0xc0e2d0dd,0xcda1f604,0xc960ebb3,
    0xbd3e8d7e,0xb9ff90c9,0xb4bcb610,0xb07daba7,
    0xae3afba2,0xaafbe615,0xa7b8c0cc,0xa379dd7b,
    0x9b3660c6,0x9ff77d71,0x92b45ba8,0x9675461f,
    0x8832161a,0x8cf30bad,0x81b02d74,0x857130c3,
    0x5d8a9099,0x594b8d2e,0x5408abf7,0x50c9b640,
    0x4e8ee645,0x4a4ffbf2,0x470cdd2b,0x43cdc09c,
    0x7b827d21,0x7f436096,0x7200464f,0x76c15bf8,
    0x68860bfd,0x6c47164a,0x61043093,0x65c52d24,
    0x119b4be9,0x155a565e,0x18197087,0x1cd86d30,
    0x029f3d35,0x065e2082,0x0b1d065b,0x0fdc1bec,
    0x3793a651,0x3352bbe6,0x3e119d3f,0x3ad08088,
    0x2497d08d,0x2056cd3a,0x2d15ebe3,0x29d4f654,
    0xc5a92679,0xc1683bce,0xcc2b1d17,0xc8ea00a0,
    0xd6ad50a5,0xd26c4d12,0xdf2f6bcb,0xdbee767c,
    0xe3a1cbc1,0xe760d676,0xea23f0af,0xeee2ed18,
    0xf0a5bd1d,0xf464a0aa,0xf9278673,0xfde69bc4,
    0x89b8fd09,0x8d79e0be,0x803ac667,0x84fbdbd0,
    0x9abc8bd5,0x9e7d9662,0x933eb0bb,0x97ffad0c,
    0xafb010b1,0xab710d06,0xa6322bdf,0xa2f33668,
    0xbcb4666d,0xb8757bda,0xb5365d03,0xb1f740b4
  };
  
  // End libogg tables
  
  
  OggPage::OggPage(void)
  {
  	mHeader = new OggPageHeader;			//Deleted in destructor.	
  }
  
  OggPage::~OggPage(void)
  {
  	delete mHeader;
  	for (unsigned long i = 0; i < mPacketList.size(); i++) {
  		delete mPacketList[i];
  	}
  }
  
  //Retusn a view on the header only
  OggPageHeader* OggPage::header() {
  	return mHeader;
  }
  
  //returns a view on the packet only.
  OggPacket* OggPage::getPacket(unsigned long inPacketNo) {
  	if (inPacketNo < numPackets()) {
  		return mPacketList[inPacketNo];
  	} else {
  		return NULL;
  	}
  }
  //Returns a view on the packet only
  StampedOggPacket* OggPage::getStampedPacket(unsigned long inPacketNo) {
  	if (inPacketNo < numPackets()) {
  		StampedOggPacket* retPacket = mPacketList[inPacketNo];
  		
  		if ((int)inPacketNo != ((int)numPackets() - (mPacketList[numPackets() - 1]->isTruncated() ? 2 : 1))) {
  			//It's not the last complete packet, so it gets a -1 stamp
  			retPacket->setTimeStamp(-1, -1, StampedOggPacket::OGG_END_ONLY);
  		} else {
  			//It is the last complete packet
  			
  			retPacket->setTimeStamp(-1, header()->GranulePos(), StampedOggPacket::OGG_END_ONLY);
  		}
  		return retPacket;
  	} else {
  		return NULL;
  	}
  }
  
  //Gives away  a pointer to the caller.
  OggPage* OggPage::clone() {
  	OggPage* retClone = new OggPage;
  	if( retClone->mHeader ) delete retClone->mHeader;
  	retClone->mHeader = mHeader->clone();
  	for (size_t i = 0; i < mPacketList.size(); i++) {
  		retClone->mPacketList.push_back((StampedOggPacket*)mPacketList[i]->clone());		//The cloned new packet is deleted in the destructor
  	}
  	
  	return retClone;
  }
  
  unsigned long OggPage::numPackets() {
  	return (unsigned long)mPacketList.size();
  }
  
  //Gives a pointer to the caller, it must delete it.
  unsigned char* OggPage::createRawPageData() {
  	unsigned char* locPage = new unsigned char[mHeader->pageSize()];		//Given to the caller
  	mHeader->rawData(locPage, mHeader->pageSize());
  
  	unsigned long locOffset = mHeader->headerSize();
  	for (size_t i = 0; i < mPacketList.size(); i++) {
  		OggPacket* locPack = mPacketList[i];
  		memcpy((void*)(locPage + locOffset), (const void*)(locPack->packetData()), locPack->packetSize());
  		locOffset += locPack->packetSize();
  	}
  	return locPage;
  }
  
  bool OggPage::addPacket(StampedOggPacket* inPacket) {
  	if (inPacket != NULL) {
  		mPacketList.push_back(inPacket);
  		return true;
  	} else {
  		return false;
  	}
  }
  
  /* n.b. This code is _duplicated_ in OggPaginator::setChecksum(), since I
     (andre) didn't want to risk unstabilising any existing code.  Zen, if feel
     like replacing OggPaginator::setChecksum() with an indirection to this,
     go for it. */
  void OggPage::computeAndSetCRCChecksum()
  {
  	unsigned long locChecksum = 0;
  	unsigned long locTemp = 0;
  	unsigned char* locHeaderBuff = new unsigned char[300];
  
  	// Set the checksum to NULL for the checksumming process.
  	header()->setCRCChecksum((unsigned long)0);
  	header()->rawData(locHeaderBuff, 300);
  
  	for(unsigned long i = 0; i < headerSize(); i++) {
  		//Create the index we use for the lookup
  		locTemp = ((locChecksum >> 24) & 0xff) ^ locHeaderBuff[i];
  		//XOR the lookup value with the the current checksum shifted left 8 bits.
  		locChecksum=(locChecksum << 8) ^ crc_lookup[locTemp];
  	}
  
  	unsigned char* locBuff = NULL;
  	for(unsigned long i = 0; i < numPackets(); i++) {
  		locBuff = getPacket(i)->packetData();			//View only don't delete.
  
  		for (unsigned long j = 0; j < getPacket(i)->packetSize(); j++) {
  			locTemp = ((locChecksum >> 24) & 0xff) ^ locBuff[j];
              locChecksum = (locChecksum << 8) ^ crc_lookup[locTemp];
  		}
  	}
  
  	header()->setCRCChecksum(locChecksum);
  }
  
  
  unsigned long OggPage::pageSize()
  {
  	return mHeader->pageSize();
  }
  unsigned long OggPage::headerSize()
  {
  	return mHeader->headerSize();
  }
  unsigned long OggPage::dataSize()
  {
  	return mHeader->dataSize();
  }
  