darwin分析

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if (isMulticastDest) { fSockets = sSocketPool.GetUDPSocketPair(INADDR_ANY, fStreamInfo.fPort, fStreamInfo.fSrcIPAddr, 0); } else { fSockets = sSocketPool.GetUDPSocketPair(fStreamInfo.fDestIPAddr, fStreamInfo.fPort, fStreamInfo.fSrcIPAddr, 0); } ... ...

// also put this stream onto the socket's queue of streams

((ReflectorSocket*)fSockets->GetSocketA())->AddSender(&fRTPSender); ((ReflectorSocket*)fSockets->GetSocketB())->AddSender(&fRTCPSender); // A broadcaster is setting up a UDP session so let the sockets update the session

if (fStreamInfo.fSetupToReceive &&qtssRTPTransportTypeUDP==transportType&&inParams!=NULL) { ((ReflectorSocket*)fSockets->GetSocketA())->AddBroadcasterSession(inParams->inClientSession); ((ReflectorSocket*)fSockets->GetSocketB())->AddBroadcasterSession(inParams->inClientSession); }

((ReflectorSocket*)fSockets->GetSocketA())->SetSSRCFilter(filterState, timeout); ((ReflectorSocket*)fSockets->GetSocketB())->SetSSRCFilter(filterState, timeout); // Always set the Rcv buf size for the sockets. This is important because the these // sockets is only useful for RTCP Rrs. // 512K

fSockets->GetSocketA()->SetSocketRcvBufSize(512 * 1024); fSockets->GetSocketB()->SetSocketRcvBufSize(512 * 1024); if (isMulticastDest) { ... ... } // 针对sdp的多播的目的地址 fStreamInfo.fPort = fSockets->GetSocketA()->GetLocalPort(); // 申请监听

fSockets->GetSocketA()->RequestEvent(EV_RE); fSockets->GetSocketB()->RequestEvent(EV_RE); // Copy the source ID and setup the ref

StrPtrLen theSourceID(fSourceIDBuf, kStreamIDSize);

ReflectorStream::GenerateSourceID(&fStreamInfo, fSourceIDBuf); fRef.Set(theSourceID, this);

（3）、AddOutput

// 寻找第一个fOutputArray[num][x] == NULL,将putInThisBucket设为num if (putInThisBucket < 0) putInThisBucket = this->FindBucket(); if (fNumBuckets <= (Uint32)putInThisBucket) this->AllocateBucketArray(putInThisBucket * 2); // 保存inOutput

for(UInt32 y=0; y

ReflectorSession

This object supports reflecting an RTP multicast stream to N RTPStreams. It spaces out the packet send times in order to maximize the randomness of the sending pattern and smooth the stream. （1）、SetupReflectorSession

fLocalSDP.Delete(); fLocalSDP.Ptr = inInfo->GetLocalSDP(&fLocalSDP.Len); // Allocate all our ReflectorStreams, using the SourceInfo delete fStreamArray;

// 音视频分为两个流，对于每个流，创建ReflectorStream对象。

fStreamArray = NEW ReflectorStream*[fSourceInfo->GetNumStreams()]; for (UInt32 x = 0; x < fSourceInfo->GetNumStreams(); x++) { ... ... if(theStreamRef == NULL) { fStreamArray[x] = NEW ReflectorStream(fSourceInfo->GetStreamInfo(x));

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}

}

fStreamArray[x]->BindSockets(inParams,inFlags, filterState, filterTimeout); fStreamArray[x]->SetEnableBuffer(this->fHasBufferedStreams);

fSourceInfo->GetStreamInfo(x)->fPort = fStreamArray[x]->GetStreamInfo()->fPort;

ReflectorStream::GenerateSourceID(fSourceInfo->GetStreamInfo(x), sStreamMap->Register(fStreamArray[x]->GetRef());

&theStreamID[0]);

（2）、AddOutput bucket = -1; lastBucket = -1; while (true) { // 针对每一个ReflectorStream调用AddOutput添加inOutput for ( ; x < fSourceInfo->GetNumStreams(); x++) { bucket = fStreamArray[x]->AddOutput(inOutput, bucket); if (bucket == -1) break; else { lastBucket = bucket; if (isClient) fStreamArray[x]->IncEyeCount(); } } ... ... } atomic_add(&fNumOutputs, 1);

QTAtom

（1）、构建函数

QTAtom::QTAtom(QTFile * File, QTFile::AtomTOCEntry * Atom, Bool16 Debug, Bool16 DeepDebug)

: fDebug(Debug), fDeepDebug(DeepDebug), fFile(File)

{ memcpy(&fTOCEntry, Atom, sizeof(QTFile::AtomTOCEntry)); }

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QTAtom_mvhd

基于QTAtom类 （1）、构建函数

QTAtom_mvhd::QTAtom_mvhd(QTFile* File, QTFile::AtomTOCEntry* TOCEntry, Bool16 Debug, Bool16

DeepDebug)

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: QTAtom(File, TOCEntry, Debug, DeepDebug) { }

（2）、Initialize()

// Parse this atom's fields. fFile为QTFile类型的对象

// 调用fFile->Read(fTOCEntry.AtomDataPos+Offset, Buffer, Length) ReadInt32(mvhdPos_VersionFlags, &tempInt32); fVersion = (Uint8)((tempInt32 >> 24) & 0x000000ff); fFlags = tempInt32 & 0x00ffffff; 通过fFile->Read读取各个参数数据保存到fCreationTime、fModificationTime... ...

QTTrack

The central point of control for a track in a QTFile.

（1）、构建函数

QTTrack::QTTrack(QTFile * File, QTFile::AtomTOCEntry * Atom, Bool16 Debug, Bool16 DeepDebug)

{ : fDebug(Debug), fDeepDebug(DeepDebug), fFile(File), ... ...

QTFile::AtomTOCEntry *tempTOCEntry; // Make a copy of the TOC entry.

memcpy(&fTOCEntry, Atom, sizeof(QTFile::AtomTOCEntry)); // Load in the track header atom for this track.

fFile->FindTOCEntry(“:tkhd”, &tempTOCEntry, &fTOCEntry)

// 创建QTAtom_tkhd类对象，并执行Initialize函数，类似于QTAtom_mvhd类。

}

fTrackHeaderAtom = NEW QTAtom_tkhd(fFile, tempTOCEntry, fDebug, fDeepDebug); fTrackHeaderAtom->Initialize();

（2）、Initialize()

// See if this track has a name and load it in. // fTOCEntry在构建函数里初始化。

if( fFile->FindTOCEntry(\, &tempTOCEntry, &fTOCEntry) ) { fTrackName = NEW char[ (SInt32) (tempTOCEntry->AtomDataLength + 1) ]; if( fTrackName != NULL ) fFile->Read(tempTOCEntry->AtomDataPos, fTrackName, (UInt32) tempTOCEntry->AtomDataLength); }

// Load in the media header atom for this track.

fFile->FindTOCEntry(\, &tempTOCEntry, &fTOCEntry)

fMediaHeaderAtom = NEW QTAtom_mdhd(fFile, tempTOCEntry, fDebug, fDeepDebug); fMediaHeaderAtom->Initialize();

// Load in the edit list atom for this track.

类似于上面那样创建并初始化fEditListAtom，并初始化fFirstEditMediaTime。 // Load in the data reference atom for this track.

创建并初始化fDataReferenceAtom。 // Load in the sample table atoms.

创建并初始化fTimeToSampleAtom、fCompTimeToSampleAtom、fSampleToChunkAtom、 fSampleDescriptionAtom、fChunkOffsetAtom、fSampleSizeAtom、fSyncSampleAtom

fIsInitialized = true;

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QTHintTrack

QTTrack的继承类，The central point of control for a hint track in a QTFile.

（1）、构建函数

QTHintTrack::QTHintTrack(QTFile * File, QTFile::AtomTOCEntry * Atom, Bool16 Debug, Bool16

: QTTrack(File, Atom, Debug, DeepDebug), ... ...

DeepDebug)

（2）、Initialize()

QTTrack::Initialize()

// Get the sample description table for this track and verify that it is an RTP track. // fSampleDescriptionAtom在QTTrack::Initialize里面创建并初始化

fSampleDescriptionAtom->FindSampleDescription(FOUR_CHARS_TO_INT('r', 't', 'p', ' '),

&sampleDescription, &sampleDescriptionLength) ::memcpy(&fMaxPacketSize, sampleDescription + 20, 4); fMaxPacketSize = ntohl(fMaxPacketSize); for( pSampleDescription = (sampleDescription + 24); pSampleDescription < (sampleDescription + sampleDescriptionLength);) { // Get the entry length and data type of this entry ::memcpy(&entryLength, pSampleDescription+0, 4); entryLength=ntohl(entryLength); ::memcpy(&dataType, pSampleDescription+4, 4); dataType = ntohl(dataType);

// Process this data type. switch(dataType) { case FOUR_CHARS_TO_INT('t', 'i', 'm', 's'):

// tims RTP timescale

::memcpy(&fRTPTimescale, pSampleDescription + 8, 4);

offset

fRTPTimescale = ntohl(fRTPTimescale); break;

case FOUR_CHARS_TO_INT('t', 's', 'r', 'o'): // tsro Timestamp random

::memcpy(&fTimestampRandomOffset, pSampleDescription + 8, 4);

random offset

fTimestampRandomOffset = ntohl(fTimestampRandomOffset); break;

case FOUR_CHARS_TO_INT('s', 'n', 'r', 'o'): // snro Sequence number

::memcpy(&fSequenceNumberRandomOffset, pSampleDescription + 8, 2);

fSequenceNumberRandomOffset = ntohl(fSequenceNumberRandomOffset); break; } pSampleDescription += entryLength; } // Load in the hint info atom for this track. 创建并初始化fHintInfoAtom // Load in the hint track reference atom for this track. 创建并初始化fHintTrackReferenceAtom // Allocate space for our track reference table. numTrackRefs = fHintTrackReferenceAtom->GetNumReferences();

fTrackRefs = NEW QTTrack *[numTrackRefs];

// Locate all of the tracks that we use, but don't initialize them until we actually try // to access them.

for( UInt32 CurRef = 0; CurRef < numTrackRefs; CurRef++ )

{

// Get the reference and make sure it's not empty.

fHintTrackReferenceAtom->TrackReferenceToTrackID(CurRef, &trackID)

// Store away a reference to this track.

fFile->FindTrack(trackID, &fTrackRefs[CurRef]);

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}

// Calculate the first RTP timestamp for this track. 设置fFirstRTPTimestamp fHintTrackInitialized = true; OSFileSource

底层的文件操作类，simple file abstraction. This file abstraction is ONLY to be used for files intended for serving。

（1）构建函数

会调用Set函数，在该函数里，调用open打开文件、调用fstat获取文件信息。 （2）Read

调用ReadFromPos或者ReadFromCache。

ReadFromPos和ReadFromCache的区别待分析！！

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QTSSFile

（1）Open // Because this is a role being executed from inside a callback, we need to make // sure that QTSS_RequestEvent will not work ？？？ ... ... curTask = theState->curTask; ... ... 调用注册QTSS_OpenFilePreProcess_Role处理的模块的处理函数。系统自带的模块没有提 供这个Role的处理。 如果返回QTSS_FileNotFound，则调用注册QTSS_OpenFile_Role处理的模块的处理函数。 QTSSPosixFileSysModule提供了这个Role的处理。 将上述找到的模块赋给fModule，后续可以通过fModule来调用该模块没有注册的Role处理