Darwin-Streaming-Server/QTFileLib/QTAtom_stsd.cpp

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// $Id: QTAtom_stsd.cpp,v 1.1 2006/01/05 13:20:36 murata Exp $
//
// QTAtom_stsd:
//   The 'stsd' QTAtom class.


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

#include "QTFile.h"

#include "QTAtom.h"
#include "QTAtom_stsd.h"
#include "OSMemory.h"


// -------------------------------------
// Constants
//
const int       stsdPos_VersionFlags        =  0;
const int       stsdPos_NumEntries          =  4;
const int       stsdPos_SampleTable         =  8;

const int       stsdDescPos_Size            =  0;
const int       stsdDescPos_DataFormat      =  4;
const int       stsdDescPos_Index           = 14;



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



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

QTAtom_stsd::~QTAtom_stsd(void)
{
    //
    // Free our variables.
    if( fSampleDescriptionTable != NULL )
        delete[] fSampleDescriptionTable;
    if( fTable != NULL )
        delete[] fTable;
}



// -------------------------------------
// Initialization functions
//
Bool16 QTAtom_stsd::Initialize(void)
{
    // Temporary vars
    UInt32      tempInt32;

    // General vars
    char        *pSampleDescriptionTable;


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

    ReadInt32(stsdPos_NumEntries, &fNumEntries);

    //
    // Read in all of the sample descriptions.
    if( fNumEntries > 0 ) {
        //
        // Allocate our description tables.
        UInt64 tableSize = fTOCEntry.AtomDataLength - 8;
		Assert(tableSize < kSInt32_Max);
        fSampleDescriptionTable = NEW char[ (SInt32) tableSize];
        if( fSampleDescriptionTable == NULL )
            return false;
        
        fTable = NEW char *[fNumEntries];
        if( fTable == NULL )
            return false;
        
        //
        // Read in the sample description table.
        ReadBytes(stsdPos_SampleTable, fSampleDescriptionTable, (UInt32) tableSize);

        //
        // Read them all in..
        pSampleDescriptionTable = fSampleDescriptionTable;
        char        *maxSampleDescriptionPtr = pSampleDescriptionTable + tableSize;
        for( UInt32 CurDesc = 0; CurDesc < fNumEntries; CurDesc++ ) {
            //
            // Associate this entry in our Table with the actual location of
            // this sample description.
            fTable[CurDesc] = pSampleDescriptionTable;
            
            //
            // Skip over this mini-atom.
            memcpy(&tempInt32, pSampleDescriptionTable, 4);
            pSampleDescriptionTable += ntohl(tempInt32);
            if (pSampleDescriptionTable > maxSampleDescriptionPtr)
            {   return false;
            }
        }
    }

    //
    // This atom has been successfully read in.
    return true;
}



// -------------------------------------
// Accessors
//
Bool16 QTAtom_stsd::FindSampleDescription(OSType DataFormat, char ** Buffer, UInt32 * Length)
{
    // Temporary vars
    UInt32      tempInt32;
    
    
    //
    // Go through all of the sample descriptions, looking for the requested
    // entry.
    for( UInt32 CurDesc = 0; CurDesc < fNumEntries; CurDesc++ ) {
        //
        // Get this entry's data format.
        memcpy(&tempInt32, fTable[CurDesc] + stsdDescPos_DataFormat, 4);
        tempInt32 = ntohl(tempInt32);

        //
        // Skip this entry if it does not match.
        if( DataFormat != tempInt32 )
            continue;
        
        //
        // We found a match; return it.
        *Buffer = fTable[CurDesc];

        memcpy(&tempInt32, fTable[CurDesc] + stsdDescPos_Size, 4);
        *Length = ntohl(tempInt32);

        return true;
    }
    
    //
    // No match was found.
    return false;
}

UInt16 QTAtom_stsd::SampleDescriptionToDataReference(UInt32 SampleDescriptionID)
{
    // Temporary vars
    UInt16      tempInt16;
    
    
    //
    // Validate our arguments.
    if( SampleDescriptionID > fNumEntries )
        return 1;
    
    //
    // Find and return the given sample's data reference index.
    memcpy(&tempInt16, fTable[SampleDescriptionID - 1] + stsdDescPos_Index, 2);
    return ntohs(tempInt16);
}



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