cbufferfile.cp
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- /* ***** BEGIN LICENSE BLOCK *****
- * Source last modified: $Id: cbufferfile.cp,v 1.1.1.1.50.3 2004/07/09 01:44:13 hubbe Exp $
- *
- * Portions Copyright (c) 1995-2004 RealNetworks, Inc. All Rights Reserved.
- *
- * The contents of this file, and the files included with this file,
- * are subject to the current version of the RealNetworks Public
- * Source License (the "RPSL") available at
- * http://www.helixcommunity.org/content/rpsl unless you have licensed
- * the file under the current version of the RealNetworks Community
- * Source License (the "RCSL") available at
- * http://www.helixcommunity.org/content/rcsl, in which case the RCSL
- * will apply. You may also obtain the license terms directly from
- * RealNetworks. You may not use this file except in compliance with
- * the RPSL or, if you have a valid RCSL with RealNetworks applicable
- * to this file, the RCSL. Please see the applicable RPSL or RCSL for
- * the rights, obligations and limitations governing use of the
- * contents of the file.
- *
- * Alternatively, the contents of this file may be used under the
- * terms of the GNU General Public License Version 2 or later (the
- * "GPL") in which case the provisions of the GPL are applicable
- * instead of those above. If you wish to allow use of your version of
- * this file only under the terms of the GPL, and not to allow others
- * to use your version of this file under the terms of either the RPSL
- * or RCSL, indicate your decision by deleting the provisions above
- * and replace them with the notice and other provisions required by
- * the GPL. If you do not delete the provisions above, a recipient may
- * use your version of this file under the terms of any one of the
- * RPSL, the RCSL or the GPL.
- *
- * This file is part of the Helix DNA Technology. RealNetworks is the
- * developer of the Original Code and owns the copyrights in the
- * portions it created.
- *
- * This file, and the files included with this file, is distributed
- * and made available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY
- * KIND, EITHER EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS
- * ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES
- * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET
- * ENJOYMENT OR NON-INFRINGEMENT.
- *
- * Technology Compatibility Kit Test Suite(s) Location:
- * http://www.helixcommunity.org/content/tck
- *
- * Contributor(s):
- *
- * ***** END LICENSE BLOCK ***** */
- #include "CBufferFile.h"
- #include "hxtypes.h"
- CBufferFile::CBufferFile (void)
- : mLow(NULL)
- , mBufSize(0)
- , mSize(0)
- , mCurPos(0)
- , mLoaded(FALSE)
- , mBytesTotal(0)
- { /* begin CBufferFile */
- } /* end CBufferFile */
- CBufferFile::~CBufferFile ()
- { /* begin ~CBufferFile */
- if(mLow) delete [] mLow;
-
- mLow = NULL;
- } /* end ~CBufferFile */
- Boolean CBufferFile::Specify(short fRefNum, long bufSize)
- {
- Boolean OK = TRUE;
- if(mLow)
- {
- delete [] mLow;
- mLow = NULL;
- }
-
- mLow = new char[bufSize];
- OK = mLow != NULL;
-
-
- if(OK)
- {
- mBufSize = mSize = bufSize;
-
- mHigh = mLow + (mSize >> 1);
- a_PB.ioCompletion = NULL;
- a_PB.ioVersNum = 0;
- a_PB.ioPermssn = fsRdPerm;
- a_PB.ioPosMode = fsFromStart;
- a_PB.ioMisc = 0;
- a_PB.ioRefNum = fRefNum;
- b_PB = a_PB;
- }
-
- return(OK);
- }
- long CBufferFile::Copy(Ptr destBuf, long numBytes)
- {
- long count;
- numBytes = numBytes <= mBytesToCopy ? numBytes : mBytesToCopy;
- if(mCurPos + numBytes < mBufSize)
- {
- count = numBytes;
- BlockMoveData(&mLow[mCurPos], destBuf, numBytes);
- mCurPos += numBytes;
- if(mCurPos > mBufSize >> 1 && fFillLow)
- {
- Load(kBufLow);
- fFillLow = FALSE;
- }
- }
- else
- {
- count = mBufSize - mCurPos;
- BlockMoveData(&mLow[mCurPos], destBuf, count);
- BlockMoveData(mLow, &destBuf[count], numBytes - count);
- mCurPos = numBytes - count;
- if(mCurPos < mBufSize >> 1 && !fFillLow)
- {
- Load(kBufHigh);
- fFillLow = TRUE;
- }
- }
-
- mBytesToCopy -= numBytes;
- return(numBytes);
- }
- long CBufferFile::Load(short loadFlag)
- {
- long count;
- Ptr buf;
- IOParam *thePB;
- switch(loadFlag)
- {
- case kBufLow:
- count = mBufSize >> 1;
- buf = mLow;
- thePB = &a_PB;
- break;
-
- case kBufHigh:
- count = mBufSize >> 1;
- buf = mHigh;
- thePB = &b_PB;
- break;
-
- case kBoth:
- count = mBufSize;
- buf = mLow;
- thePB = &a_PB;
- break;
-
- default:
- count = 0;
- break;
- }
- count = count <= mBytesRemaining ? count : mBytesRemaining;
-
- if(count > 0)
- {
- thePB->ioReqCount = count;
- thePB->ioPosOffset = ioPosOffset;
- thePB->ioBuffer = buf;
- thePB->ioVersNum = 0;
- thePB->ioMisc = 0;
-
- PBReadSync((ParmBlkPtr)thePB);
-
- mBytesRemaining -= count;
- ioPosOffset += count;
- }
- return(count);
- }
- Boolean CBufferFile::PreLoad(long startPos, long bytesReq)
- {
- long count;
- Boolean OK;
- OSErr theErr;
-
- count = (bytesReq <= mSize) ? bytesReq : mSize;
- mBufSize = count;
- mHigh = mLow + (count >> 1);
-
- mCurPos = 0;
- mStartPos = startPos;
- mBytesTotal = bytesReq;
- mBytesRemaining = bytesReq;
- mBytesToCopy = bytesReq;
- ioPosOffset = startPos;
- a_PB.ioMisc = 0;
- a_PB.ioVersNum = 0;
- a_PB.ioResult = 0;
- a_PB.ioReqCount = count;
- a_PB.ioPosOffset = startPos;
- a_PB.ioBuffer = mLow;
- b_PB = a_PB;
-
- theErr = PBReadSync((ParmBlkPtr)&a_PB);
-
- OK = theErr == noErr;
- if(OK)
- {
- mBytesRemaining -= count;
- ioPosOffset += count;
- fFillLow = TRUE;
- }
- else if(theErr == eofErr)
- {
- mBytesRemaining = 0;
- ioPosOffset += count;
- fFillLow = TRUE;
- OK = TRUE;
- }
-
- mLoaded = OK;
- return(OK);
- }
- void CBufferFile::CheckBuffer(void)
- {
- if(mCurPos > mBufSize >> 1 && fFillLow)
- {
- Load(kBufLow);
- fFillLow = FALSE;
- }
- else if(mCurPos < mBufSize >> 1 && !fFillLow)
- {
- Load(kBufHigh);
- fFillLow = TRUE;
- }
- }