Darwin-Streaming-Server/QTFileLib/QTAtom_stss.cpp

/*
 *
 * @APPLE_LICENSE_HEADER_START@
 *
 * Copyright (c) 1999-2008 Apple Inc.  All Rights Reserved.
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 *
 */
// $Id: QTAtom_stss.cpp,v 1.2 2006/03/29 00:47:00 murata Exp $
//
// QTAtom_stss:
//   The 'stss' QTAtom class.


// -------------------------------------
// Includes
//
#include <stdio.h>
#include <stdlib.h>
#include "SafeStdLib.h"
#ifndef __Win32__
#include <sys/types.h>
#include <netinet/in.h>
#endif

#include "QTFile.h"

#include "QTAtom.h"
#include "QTAtom_stss.h"
#include "OSMemory.h"


// -------------------------------------
// Constants
//
const int       stssPos_VersionFlags        =  0;
const int       stssPos_NumEntries          =  4;
const int       stssPos_SampleTable         =  8;



// -------------------------------------
// Macros
//
#define DEBUG_PRINT(s) if(fDebug) qtss_printf s
#define DEEP_DEBUG_PRINT(s) if(fDeepDebug) qtss_printf s



// -------------------------------------
// Constructors and destructors
//
QTAtom_stss::QTAtom_stss(QTFile * File, QTFile::AtomTOCEntry * TOCEntry, Bool16 Debug, Bool16 DeepDebug)
    : QTAtom(File, TOCEntry, Debug, DeepDebug),
      fNumEntries(0), fSyncSampleTable(NULL), fTable(NULL), fTableSize(0)
{
}

QTAtom_stss::~QTAtom_stss(void)
{
    //
    // Free our variables.
#if MMAP_TABLES
    if( fSyncSampleTable != NULL )
        this->UnMap(fSyncSampleTable, fTableSize);
#else
    if( fSyncSampleTable != NULL )
        delete[] fSyncSampleTable;
#endif
}



// -------------------------------------
// Initialization functions
//
Bool16 QTAtom_stss::Initialize(void)
{
    Bool16      initSucceeds = false;
    UInt32      tempInt32;


    //
    // Parse this atom's fields.
    initSucceeds = ReadInt32(stssPos_VersionFlags, &tempInt32);
    fVersion = (UInt8)((tempInt32 >> 24) & 0x000000ff);
    fFlags = tempInt32 & 0x00ffffff;

    if ( initSucceeds )
    {   
        initSucceeds = ReadInt32(stssPos_NumEntries, &fNumEntries);

        //
        // Validate the size of the sample table.
        if( (UInt32)(fNumEntries * 4) != (fTOCEntry.AtomDataLength - 8) )
            return false;

        
#if 0// MMAP_TABLES needs fixing should be page aligned and maybe on a 64bit system the whole file should be mapped.
    fTableSize = (fNumEntries * 4);
    fSyncSampleTable = this->MemMap(stssPos_SampleTable, fTableSize);
    fTable = (UInt32 *) fSyncSampleTable;
    if (fSyncSampleTable == NULL)
        return false;
        
#else
        //
        // Read in the sync sample table.
        fSyncSampleTable = NEW char[(fNumEntries * 4) + 1];
        if( fSyncSampleTable == NULL )
            return false;
        
        if( ((PointerSizedInt)fSyncSampleTable & (PointerSizedInt)0x3) == 0)
            fTable = (UInt32 *)fSyncSampleTable;
        else
            fTable = (UInt32 *)(((PointerSizedInt)fSyncSampleTable + 4) & ~((PointerSizedInt)0x3));
        
        initSucceeds = ReadBytes(stssPos_SampleTable, (char *)fTable, fNumEntries * 4);
 
#endif

        if ( initSucceeds )
        {
            // This atom has been successfully read in.
            // sample offsets are in network byte order on disk, convert them to host order
            UInt32      sampleIndex = 0;
            
            // convert each sample to host order
            // NOTE - most other Atoms handle byte order conversions in
            // the accessor function.  For efficiency reasons it's converted
            // to host order here for sync samples.
            
            for ( sampleIndex = 0; sampleIndex < fNumEntries; sampleIndex++ )
            {
                fTable[sampleIndex] = ntohl( fTable[sampleIndex] );
            
            }
        
        }



    }
    
    return initSucceeds;
}



// -------------------------------------
// Accessors
//
void QTAtom_stss::PreviousSyncSample(UInt32 SampleNumber, UInt32 *SyncSampleNumber)
{
    //
    // We assume that we won't find an answer
    *SyncSampleNumber = SampleNumber;
    
    //
    // Scan the table until we find a sample number greater than our current
    // sample number; then return that.
    for( UInt32 CurEntry = 0; CurEntry < fNumEntries; CurEntry++ ) {
        //
        // Take this entry if it is before (or equal to) our current entry.
        if( fTable[CurEntry] <= SampleNumber )
            *SyncSampleNumber = fTable[CurEntry];
    }
}

void QTAtom_stss::NextSyncSample(UInt32 SampleNumber, UInt32 *SyncSampleNumber)
{
    //
    // We assume that we won't find an answer
    *SyncSampleNumber = SampleNumber + 1;
    
    //
    // Scan the table until we find a sample number greater than our current
    // sample number; then return that.
    for( UInt32 CurEntry = 0; CurEntry < fNumEntries; CurEntry++ ) {
        //
        // Take this entry if it is greater than our current entry.
        if( fTable[CurEntry] > SampleNumber ) {
            *SyncSampleNumber = fTable[CurEntry];
            break;
        }
    }
}


// -------------------------------------
// Debugging functions
//
void QTAtom_stss::DumpAtom(void)
{
    DEBUG_PRINT(("QTAtom_stss::DumpAtom - Dumping atom.\n"));
    DEBUG_PRINT(("QTAtom_stss::DumpAtom - ..Number of sync sample entries: %"_S32BITARG_"\n", fNumEntries));
}

void QTAtom_stss::DumpTable(void)
{
    //
    // Print out a header.
    qtss_printf("-- Sync Sample table -----------------------------------------------------------\n");
    qtss_printf("\n");
    qtss_printf("  Entry Num.   Sample Num\n");
    qtss_printf("  ----------   ----------\n");
    
    //
    // Print the table.
    for( UInt32 CurEntry = 1; CurEntry <= fNumEntries; CurEntry++ ) {
        //
        // Print out a listing.
        qtss_printf("  %10"_U32BITARG_" : %10"_U32BITARG_"\n", CurEntry, fTable[CurEntry-1]);
    }
}