void HTTPRequest::AppendDateField()
{
Assert(OSThread::GetCurrent() != NULL);
DateBuffer* theDateBuffer = OSThread::GetCurrent()->GetDateBuffer();
theDateBuffer->InexactUpdate(); // Update the date buffer to the current date & time
StrPtrLen theDate(theDateBuffer->GetDateBuffer(), DateBuffer::kDateBufferLen);
// Append date
this->AppendResponseHeader(httpDateHeader, &theDate);
}
void HTTPRequest::AppendDateAndExpiresFields()
{
Assert(OSThread::GetCurrent() != NULL);
DateBuffer* theDateBuffer = OSThread::GetCurrent()->GetDateBuffer();
theDateBuffer->InexactUpdate(); // Update the date buffer to the current date & time
StrPtrLen theDate(theDateBuffer->GetDateBuffer(), DateBuffer::kDateBufferLen);
// Append dates, and have this response expire immediately
this->AppendResponseHeader(httpDateHeader, &theDate);
this->AppendResponseHeader(httpExpiresHeader, &theDate);
}
void RTSPRequestInterface::AppendDateAndExpires()
{
if (!fStandardHeadersWritten)
this->WriteStandardHeaders();
Assert(OSThread::GetCurrent() != NULL);
DateBuffer* theDateBuffer = OSThread::GetCurrent()->GetDateBuffer();
theDateBuffer->InexactUpdate(); // Update the date buffer to the current date & time
StrPtrLen theDate(theDateBuffer->GetDateBuffer(), DateBuffer::kDateBufferLen);
// Append dates, and have this response expire immediately
this->AppendHeader(qtssDateHeader, &theDate);
this->AppendHeader(qtssExpiresHeader, &theDate);
}
QTSS_Error HTTPResponseStream::Flush()
{
UInt32 amtInBuffer = this->GetCurrentOffset() - fBytesSentInBuffer;
if (amtInBuffer > 0)
{
if (fPrintMSG)
{
DateBuffer theDate;
DateTranslator::UpdateDateBuffer(&theDate, 0); // get the current GMT date and time
qtss_printf("\n#S->C:\n#time: ms=%" _U32BITARG_ " date=%s\n", (UInt32)OS::StartTimeMilli_Int(), theDate.GetDateBuffer());
StrPtrLen str(this->GetBufPtr() + fBytesSentInBuffer, amtInBuffer);
str.PrintStrEOL();
}
UInt32 theLengthSent = 0;
//(void)fSocket->Send(this->GetBufPtr() + fBytesSentInBuffer, amtInBuffer, &theLengthSent);
QTSS_Error theErr = fSocket->Send(this->GetBufPtr() + fBytesSentInBuffer, amtInBuffer, &theLengthSent);
if ((theErr != QTSS_NoErr) && (theErr != EAGAIN))
{
return theErr;
}
// Refresh the timeout if we were able to send any data
if (theLengthSent > 0)
fTimeoutTask->RefreshTimeout();
if (theLengthSent == amtInBuffer)
{
// We were able to send all the data in the buffer. Great. Flush it.
this->Reset();
fBytesSentInBuffer = 0;
}
else
{
// Not all the data was sent, so report an EAGAIN
fBytesSentInBuffer += theLengthSent;
Assert(fBytesSentInBuffer < this->GetCurrentOffset());
return EAGAIN;
}
}
return QTSS_NoErr;
}
/* 先统计buffer中还有多少待送出的数据,再用Socket::Send()向外发送数据.只要能够送出数据,就refresh timeout.假如一次全部送出数据,就flush清空它,否则累计已送出的数据,返回EAGAIN */
QTSS_Error RTSPResponseStream::Flush()
{
/* 得到剩余数据的长度 */
UInt32 amtInBuffer = this->GetCurrentOffset() - fBytesSentInBuffer;
if (amtInBuffer > 0)
{
/*********** 逐行打印出剩余数据的信息,注意打印信息就是从这里出来的 **************/
if (fPrintRTSP)
{
DateBuffer theDate;
DateTranslator::UpdateDateBuffer(&theDate, 0); // get the current GMT date and time
qtss_printf("\n#S->C:\n#time: ms=%lu date=%s\n", (UInt32) OS::StartTimeMilli_Int(), theDate.GetDateBuffer() );
StrPtrLen str(this->GetBufPtr() + fBytesSentInBuffer, amtInBuffer);
str.PrintStrEOL();
}
UInt32 theLengthSent = 0;
/* 使用TCPSocket发送出RTSP Response流缓存中剩余的数据,实际发送数据长为theLengthSent */
(void)fSocket->Send(this->GetBufPtr() + fBytesSentInBuffer, amtInBuffer, &theLengthSent);
// Refresh the timeout if we were able to send any data
/* 只要能发送出数据,就刷新超时 */
if (theLengthSent > 0)
fTimeoutTask->RefreshTimeout();
/* 假如成功发送出所有数据,就重置缓冲区指针和已发送数据长度 */
if (theLengthSent == amtInBuffer)
{
// We were able to send all the data in the buffer. Great. Flush it.
this->Reset();
fBytesSentInBuffer = 0;
}
else
{
// Not all the data was sent, so report an EAGAIN
/* 否则,累计发送出的数据,返回EAGAIN */
fBytesSentInBuffer += theLengthSent;
Assert(fBytesSentInBuffer < this->GetCurrentOffset());
return EAGAIN;
}
}
return QTSS_NoErr;
}
QTSS_Error HTTPResponseStream::WriteV(iovec* inVec, UInt32 inNumVectors, UInt32 inTotalLength,
UInt32* outLengthSent, UInt32 inSendType)
{
QTSS_Error theErr = QTSS_NoErr;
UInt32 theLengthSent = 0;
UInt32 amtInBuffer = this->GetCurrentOffset() - fBytesSentInBuffer;
if (amtInBuffer > 0)
{
// There is some data in the output buffer. Make sure to send that
// first, using the empty space in the ioVec.
inVec[0].iov_base = this->GetBufPtr() + fBytesSentInBuffer;
inVec[0].iov_len = amtInBuffer;
theErr = fSocket->GetSocket()->WriteV(inVec, inNumVectors, &theLengthSent);
if (fPrintMsg)
{
DateBuffer theDate;
DateTranslator::UpdateDateBuffer(&theDate, 0); // get the current GMT date and time
qtss_printf("\n#S->C:\n#time: ms=%"_U32BITARG_" date=%s\n", (UInt32) OS::StartTimeMilli_Int(), theDate.GetDateBuffer() );
for (UInt32 i =0; i < inNumVectors; i++)
{ StrPtrLen str((char*)inVec[i].iov_base, (UInt32) inVec[i].iov_len);
str.PrintStrEOL();
}
}
if (theLengthSent >= amtInBuffer)
{
// We were able to send all the data in the buffer. Great. Flush it.
this->Reset();
fBytesSentInBuffer = 0;
// Make theLengthSent reflect the amount of data sent in the ioVec
theLengthSent -= amtInBuffer;
}
else
{
// Uh oh. Not all the data in the buffer was sent. Update the
// fBytesSentInBuffer count, and set theLengthSent to 0.
fBytesSentInBuffer += theLengthSent;
Assert(fBytesSentInBuffer < this->GetCurrentOffset());
theLengthSent = 0;
}
// theLengthSent now represents how much data in the ioVec was sent
}
else if (inNumVectors > 1)
{
theErr = fSocket->GetSocket()->WriteV(&inVec[1], inNumVectors - 1, &theLengthSent);
}
// We are supposed to refresh the timeout if there is a successful write.
if (theErr == QTSS_NoErr)
fTimeoutTask->RefreshTimeout();
// If there was an error, don't alter anything, just bail
if ((theErr != QTSS_NoErr) && (theErr != EAGAIN))
return theErr;
// theLengthSent at this point is the amount of data passed into
// this function that was sent.
if (outLengthSent != NULL)
*outLengthSent = theLengthSent;
// Update the StringFormatter fBytesWritten variable... this data
// wasn't buffered in the output buffer at any time, so if we
// don't do this, this amount would get lost
fBytesWritten += theLengthSent;
// All of the data was sent... whew!
if (theLengthSent == inTotalLength)
return QTSS_NoErr;
// We need to determine now whether to copy the remaining unsent
// iovec data into the buffer. This is determined based on
// the inSendType parameter passed in.
if (inSendType == kDontBuffer)
return theErr;
if ((inSendType == kAllOrNothing) && (theLengthSent == 0))
return EAGAIN;
// Some or none of the iovec data was sent. Copy the remainder into the output
// buffer.
// The caller should consider this data sent.
if (outLengthSent != NULL)
*outLengthSent = inTotalLength;
UInt32 curVec = 1;
while (theLengthSent >= inVec[curVec].iov_len)
{
// Skip over the vectors that were in fact sent.
Assert(curVec < inNumVectors);
theLengthSent -= inVec[curVec].iov_len;
curVec++;
}
while (curVec < inNumVectors)
{
// Copy the remaining vectors into the buffer
this->Put( ((char*)inVec[curVec].iov_base) + theLengthSent,
inVec[curVec].iov_len - theLengthSent);
theLengthSent = 0;
curVec++;
}
return QTSS_NoErr;
}
QTSS_Error HTTPResponseStream::Flush()
{
QTSS_Error theErr = QTSS_NoErr;
while(true)
{
// 获取缓冲区中需要发送的数据长度
UInt32 amtInBuffer = this->GetCurrentOffset() - fBytesSentInBuffer;
// 多次发送缓冲区中的数据
if (amtInBuffer > QTSS_MAX_REQUEST_BUFFER_SIZE)
amtInBuffer = QTSS_MAX_REQUEST_BUFFER_SIZE;
printf("this->GetCurrentOffset(%d) - fBytesSentInBuffer(%d) = amtInBuffer(%d)\n", this->GetCurrentOffset(), fBytesSentInBuffer, amtInBuffer);
if (amtInBuffer > 0)
{
if (fPrintMsg)
{
DateBuffer theDate;
DateTranslator::UpdateDateBuffer(&theDate, 0); // get the current GMT date and time
qtss_printf("\n#S->C:\n#time: ms=%"_U32BITARG_" date=%s\n", (UInt32) OS::StartTimeMilli_Int(), theDate.GetDateBuffer() );
StrPtrLen str(this->GetBufPtr() + fBytesSentInBuffer, amtInBuffer);
str.PrintStrEOL();
}
//UInt32 theLengthSent = 0;
//(void)fSocket->GetSocket()->Send(this->GetBufPtr() + fBytesSentInBuffer, amtInBuffer, &theLengthSent);
theErr = fSocket->Send(this->GetBufPtr() + fBytesSentInBuffer, amtInBuffer);
//// Refresh the timeout if we were able to send any data
//if (theLengthSent > 0)
// fTimeoutTask->RefreshTimeout();
// 单次发送成功,继续发送
if (theErr == OS_NoErr)
{
fBytesSentInBuffer += amtInBuffer;
Assert(fBytesSentInBuffer < this->GetCurrentOffset());
}
else
return theErr;
if(fBytesSentInBuffer < this->GetCurrentOffset())
{
continue;
}
else
{
// We were able to send all the data in the buffer. Great. Flush it.
this->Reset();
fBytesSentInBuffer = 0;
break;
}
}
else
{
// We were able to send all the data in the buffer. Great. Flush it.
this->Reset();
fBytesSentInBuffer = 0;
break;
}
}
return theErr;
}
QTSS_Error RTSPRequestStream::ReadRequest()
{
while (true)
{
UInt32 newOffset = 0;
//If this is the case, we already HAVE a request on this session, and we now are done
//with the request and want to move onto the next one. The first thing we should do
//is check whether there is any lingering data in the stream. If there is, the parent
//session believes that is part of a new request
if (fRequestPtr != NULL)
{
fRequestPtr = NULL;//flag that we no longer have a complete request
// Take all the retreated leftover data and move it to the beginning of the buffer
if ((fRetreatBytes > 0) && (fRequest.Len > 0))
::memmove(fRequest.Ptr, fRequest.Ptr + fRequest.Len + fRetreatBytesRead, fRetreatBytes);
// if we are decoding, we need to also move over the remaining encoded bytes
// to the right position in the fRequestBuffer
if (fEncodedBytesRemaining > 0)
{
//Assert(fEncodedBytesRemaining < 4);
// The right position is at fRetreatBytes offset in the request buffer. The reason for this is:
// 1) We need to find a place in the request buffer where we know we have enough space to store
// fEncodedBytesRemaining. fRetreatBytes + fEncodedBytesRemaining will always be less than
// kRequestBufferSize because all this data must have been in the same request buffer, together, at one point.
//
// 2) We need to make sure that there is always more data in the RequestBuffer than in the decoded
// request buffer, otherwise we could overrun the decoded request buffer (we bounds check on the encoded
// buffer, not the decoded buffer). Leaving fRetreatBytes as empty space in the request buffer ensures
// that this principle is maintained.
::memmove(&fRequestBuffer[fRetreatBytes], &fRequestBuffer[fCurOffset - fEncodedBytesRemaining], fEncodedBytesRemaining);
fCurOffset = fRetreatBytes + fEncodedBytesRemaining;
Assert(fCurOffset < kRequestBufferSizeInBytes);
}
else
fCurOffset = fRetreatBytes;
newOffset = fRequest.Len = fRetreatBytes;
fRetreatBytes = fRetreatBytesRead = 0;
}
// We don't have any new data, so try and get some
if (newOffset == 0)
{
if (fRetreatBytes > 0)
{
// This will be true if we've just snarfed another input stream, in which case the encoded data
// is copied into our request buffer, and its length is tracked in fRetreatBytes.
// If this is true, just fall through and decode the data.
newOffset = fRetreatBytes;
fRetreatBytes = 0;
Assert(fEncodedBytesRemaining == 0);
}
else
{
// We don't have any new data, get some from the socket...
QTSS_Error sockErr = fSocket->Read(&fRequestBuffer[fCurOffset],
(kRequestBufferSizeInBytes - fCurOffset) - 1, &newOffset);
//assume the client is dead if we get an error back
if (sockErr == EAGAIN)
return QTSS_NoErr;
if (sockErr != QTSS_NoErr)
{
Assert(!fSocket->IsConnected());
return sockErr;
}
}
if (fDecode)
{
// If we need to decode this data, do it now.
Assert(fCurOffset >= fEncodedBytesRemaining);
QTSS_Error decodeErr = this->DecodeIncomingData(&fRequestBuffer[fCurOffset - fEncodedBytesRemaining],
newOffset + fEncodedBytesRemaining);
// If the above function returns an error, it is because we've
// encountered some non-base64 data in the stream. We can process
// everything up until that point, but all data after this point will
// be ignored.
if (decodeErr == QTSS_NoErr)
Assert(fEncodedBytesRemaining < 4);
}
else
fRequest.Len += newOffset;
Assert(fRequest.Len < kRequestBufferSizeInBytes);
fCurOffset += newOffset;
}
Assert(newOffset > 0);
// See if this is an interleaved data packet
if ('$' == *(fRequest.Ptr))
{
if (fRequest.Len < 4)
continue;
UInt16* dataLenP = (UInt16*)fRequest.Ptr;
UInt32 interleavedPacketLen = ntohs(dataLenP[1]) + 4;
if (interleavedPacketLen > fRequest.Len)
continue;
//put back any data that is not part of the header
fRetreatBytes += fRequest.Len - interleavedPacketLen;
fRequest.Len = interleavedPacketLen;
fRequestPtr = &fRequest;
fIsDataPacket = true;
return QTSS_RequestArrived;
}
fIsDataPacket = false;
if (fPrintRTSP)
{
DateBuffer theDate;
DateTranslator::UpdateDateBuffer(&theDate, 0); // get the current GMT date and time
qtss_printf("\n\n#C->S:\n#time: ms=%lu date=%s\n", (UInt32) OS::StartTimeMilli_Int(), theDate.GetDateBuffer());
if (fSocket != NULL)
{
UInt16 serverPort = fSocket->GetLocalPort();
UInt16 clientPort = fSocket->GetRemotePort();
StrPtrLen* theLocalAddrStr = fSocket->GetLocalAddrStr();
StrPtrLen* theRemoteAddrStr = fSocket->GetRemoteAddrStr();
if (theLocalAddrStr != NULL)
{ qtss_printf("#server: ip="); theLocalAddrStr->PrintStr(); qtss_printf(" port=%u\n" , serverPort );
}
else
{ qtss_printf("#server: ip=NULL port=%u\n" , serverPort );
}
if (theRemoteAddrStr != NULL)
{ qtss_printf("#client: ip="); theRemoteAddrStr->PrintStr(); qtss_printf(" port=%u\n" , clientPort );
}
else
{ qtss_printf("#client: ip=NULL port=%u\n" , clientPort );
}
}
StrPtrLen str(fRequest);
str.PrintStrEOL("\n\r\n", "\n");// print the request but stop on \n\r\n and add a \n afterwards.
}
//use a StringParser object to search for a double EOL, which signifies the end of
//the header.
Bool16 weAreDone = false;
StringParser headerParser(&fRequest);
UInt16 lcount = 0;
while (headerParser.GetThruEOL(NULL))
{
lcount++;
if (headerParser.ExpectEOL())
{
//The legal end-of-header sequences are \r\r, \r\n\r\n, & \n\n. NOT \r\n\r!
//If the packets arrive just a certain way, we could get here with the latter
//combo, and not wait for a final \n.
if ((headerParser.GetDataParsedLen() > 2) &&
(memcmp(headerParser.GetCurrentPosition() - 3, "\r\n\r", 3) == 0))
continue;
weAreDone = true;
break;
}
else if (lcount == 1) {
// if this request is actually a ShoutCast password it will be
// in the form of "xxxxxx\r" where "xxxxx" is the password.
// If we get a 1st request line ending in \r with no blanks we will
// assume that this is the end of the request.
UInt16 flag = 0;
UInt16 i = 0;
for (i=0; i<fRequest.Len; i++)
{
if (fRequest.Ptr[i] == ' ')
flag++;
}
if (flag == 0)
{
weAreDone = true;
break;
}
}
}
//weAreDone means we have gotten a full request
if (weAreDone)
{
//put back any data that is not part of the header
fRequest.Len -= headerParser.GetDataRemaining();
fRetreatBytes += headerParser.GetDataRemaining();
fRequestPtr = &fRequest;
return QTSS_RequestArrived;
}
//check for a full buffer
if (fCurOffset == kRequestBufferSizeInBytes - 1)
{
fRequestPtr = &fRequest;
return E2BIG;
}
}
}
QTSS_Error QTSSModuleUtils::SendHTTPErrorResponse( QTSS_RTSPRequestObject inRequest,
QTSS_SessionStatusCode inStatusCode,
Bool16 inKillSession,
char *errorMessage)
{
static Bool16 sFalse = false;
//set status code for access log
(void)QTSS_SetValue(inRequest, qtssRTSPReqStatusCode, 0, &inStatusCode, sizeof(inStatusCode));
if (inKillSession) // tell the server to end the session
(void)QTSS_SetValue(inRequest, qtssRTSPReqRespKeepAlive, 0, &sFalse, sizeof(sFalse));
ResizeableStringFormatter theErrorMessage(NULL, 0); //allocates and deletes memory
ResizeableStringFormatter bodyMessage(NULL,0); //allocates and deletes memory
char messageLineBuffer[64]; // used for each line
static const int maxMessageBufferChars = sizeof(messageLineBuffer) -1;
messageLineBuffer[maxMessageBufferChars] = 0; // guarantee termination
// ToDo: put in a more meaningful http error message for each error. Not required by spec.
// ToDo: maybe use the HTTP protcol class static error strings.
char* errorMsg = "error";
DateBuffer theDate;
DateTranslator::UpdateDateBuffer(&theDate, 0); // get the current GMT date and time
UInt32 realCode = 0;
UInt32 len = sizeof(realCode);
(void) QTSS_GetValue(inRequest, qtssRTSPReqRealStatusCode, 0, (void*)&realCode,&len);
char serverHeaderBuffer[64]; // the qtss Server: header field
len = sizeof(serverHeaderBuffer) -1; // leave room for terminator
(void) QTSS_GetValue(sServer, qtssSvrRTSPServerHeader, 0, (void*)serverHeaderBuffer,&len);
serverHeaderBuffer[len] = 0; // terminate.
qtss_snprintf(messageLineBuffer,maxMessageBufferChars, "HTTP/1.1 %"_U32BITARG_" %s",realCode, errorMsg);
theErrorMessage.Put(messageLineBuffer,::strlen(messageLineBuffer));
theErrorMessage.PutEOL();
theErrorMessage.Put(serverHeaderBuffer,::strlen(serverHeaderBuffer));
theErrorMessage.PutEOL();
qtss_snprintf(messageLineBuffer,maxMessageBufferChars, "Date: %s",theDate.GetDateBuffer());
theErrorMessage.Put(messageLineBuffer,::strlen(messageLineBuffer));
theErrorMessage.PutEOL();
Bool16 addBody = (errorMessage != NULL && ::strlen(errorMessage) != 0); // body error message so add body headers
if (addBody) // body error message so add body headers
{
// first create the html body
static const StrPtrLen htmlBodyStart("<html><body>\n");
bodyMessage.Put(htmlBodyStart.Ptr,htmlBodyStart.Len);
//<h1>errorMessage</h1>\n
static const StrPtrLen hStart("<h1>");
bodyMessage.Put(hStart.Ptr,hStart.Len);
bodyMessage.Put(errorMessage,::strlen(errorMessage));
static const StrPtrLen hTerm("</h1>\n");
bodyMessage.Put(hTerm.Ptr,hTerm.Len);
static const StrPtrLen htmlBodyTerm("</body></html>\n");
bodyMessage.Put(htmlBodyTerm.Ptr,htmlBodyTerm.Len);
// write body headers
static const StrPtrLen bodyHeaderType("Content-Type: text/html");
theErrorMessage.Put(bodyHeaderType.Ptr,bodyHeaderType.Len);
theErrorMessage.PutEOL();
qtss_snprintf(messageLineBuffer,maxMessageBufferChars, "Content-Length: %"_U32BITARG_"", bodyMessage.GetBytesWritten());
theErrorMessage.Put(messageLineBuffer,::strlen(messageLineBuffer));
theErrorMessage.PutEOL();
}
static const StrPtrLen headerClose("Connection: close");
theErrorMessage.Put(headerClose.Ptr,headerClose.Len);
theErrorMessage.PutEOL();
theErrorMessage.PutEOL(); // terminate headers with empty line
if (addBody) // add html body
{
theErrorMessage.Put(bodyMessage.GetBufPtr(),bodyMessage.GetBytesWritten());
}
//
// Now that we've formatted the message into the temporary buffer,
// write it out to the request stream and the Client Session object
(void)QTSS_Write(inRequest, theErrorMessage.GetBufPtr(), theErrorMessage.GetBytesWritten(), NULL, 0);
(void)QTSS_SetValue(inRequest, qtssRTSPReqRespMsg, 0, theErrorMessage.GetBufPtr(), theErrorMessage.GetBytesWritten());
return QTSS_RequestFailed;
}
/* 使用writev(),若RTSP Response流的缓冲区中有待发数据,首先将其发送出去,否则将其他缓冲区的数据发送出,
并刷新超时任务,最后比较发送的总长度outLengthSent与要发送数据总长度inTotalLength的差值,将该段剩余数据
以及随后的iovec放入缓冲区待发送,依据第5个参数决定是否缓存(利用StringFormatter::Put())没有发送出的iovec data?
*/
QTSS_Error RTSPResponseStream::WriteV(iovec* inVec, UInt32 inNumVectors, UInt32 inTotalLength,
UInt32* outLengthSent, UInt32 inSendType)
{
QTSS_Error theErr = QTSS_NoErr;
/* 用TCPSocket已经送出数据的长度,注意这个量十分重要 */
UInt32 theLengthSent = 0;
/* 缓存中剩余data的字节数 */
UInt32 amtInBuffer = this->GetCurrentOffset() - fBytesSentInBuffer;
/* 假如buffer中还有剩余数据,就把它用Socket写入RTSP Response流中 */
if (amtInBuffer > 0)
{
// There is some data in the output buffer. Make sure to send that
// first, using the empty space in the ioVec.
/* 确定buffer中剩余数据的起点和长度,配置为inVec的第一个分量 */
inVec[0].iov_base = this->GetBufPtr() + fBytesSentInBuffer;
inVec[0].iov_len = amtInBuffer;
/* 用Socket::Writev()写入数据,送出的数据长度是theLengthSent */
theErr = fSocket->WriteV(inVec, inNumVectors, &theLengthSent);
/* 假如打印RTSP信息,就输出RTSP Response的指定格式的信息 */
if (fPrintRTSP)
{
/* 类似RTSPRequestStream::ReadRequest() */
/* 得到当前的GTM时间,格式为"Mon, 04 Nov 1996 21:42:17 GMT",并打印这些信息 */
DateBuffer theDate;
DateTranslator::UpdateDateBuffer(&theDate, 0); // get the current GMT date and time
qtss_printf("\n#S->C:\n#time: ms=%lu date=%s\n", (UInt32) OS::StartTimeMilli_Int(), theDate.GetDateBuffer() );
/* 对每个向量,逐行打印其被'\n'或'\r'分割的内容(多个C-String)和'\n'或'\r' */
for (UInt32 i =0; i < inNumVectors; i++)
{
StrPtrLen str((char*)inVec[i].iov_base, (UInt32) inVec[i].iov_len);
str.PrintStrEOL();
}
}
/* 假如TCPSocket送出的数据超过了剩余要送的数据,将当前指针fCurrentPut移动开头,更新相应量 */
if (theLengthSent >= amtInBuffer)
{
// We were able to send all the data in the buffer. Great(好极了). Flush it.
/* 根据入参0重置fCurrentPut的位置为fStartPut,即,将当前指针移动开头 */
this->Reset();
/* 更新,此时buffer中没有数据要送 */
fBytesSentInBuffer = 0;
// Make theLengthSent reflect the amount of data sent in the ioVec
/* 及时更新theLengthSent */
theLengthSent -= amtInBuffer;
}
else /* 还有数据没有送完 */
{
// Uh oh. Not all the data in the buffer was sent. Update the
// fBytesSentInBuffer count, and set theLengthSent to 0.
/* 累计buffer中TCPSocket送出数据的总字节数 */
fBytesSentInBuffer += theLengthSent;
Assert(fBytesSentInBuffer < this->GetCurrentOffset());
/* 以便下次用fSocket->WriteV() */
theLengthSent = 0;
}
// theLengthSent now represents how much data in the ioVec was sent
}/* 假如当前buffer中没有数据,就从第二个向量开始发送其它向量中的数据,其实际发送数据的长度是theLengthSent */
else if (inNumVectors > 1)
{
theErr = fSocket->WriteV(&inVec[1], inNumVectors - 1, &theLengthSent);
}
// We are supposed to refresh the timeout if there is a successful write.
if (theErr == QTSS_NoErr)
fTimeoutTask->RefreshTimeout();
// If there was an error, don't alter anything, just bail
/* 假如Socket::WriteV()结果不是送完或者还要送,就返回实际错误 */
if ((theErr != QTSS_NoErr) && (theErr != EAGAIN))
return theErr;
// theLengthSent at this point is the amount of data passed into
// this function that was sent.
/* 记录使用fSocket->WriteV()时输出数据的总长度,后面会对这个值更新 */
if (outLengthSent != NULL)
*outLengthSent = theLengthSent;
// Update the StringFormatter fBytesWritten variable... this data
// wasn't buffered in the output buffer at any time, so if we
// don't do this, this amount would get lost
// A way of keeping count of how many bytes have been written total,see StringFormatter.h
/* 计算共有多少字节被写入,将统计信息加入fBytesWritten,以防丢失 */
fBytesWritten += theLengthSent;
// All of the data was sent... whew!
/* 假如所有的数据被发送出,正确返回 */
if (theLengthSent == inTotalLength)
return QTSS_NoErr;
/* 下面根据第5个参数决定是否缓存剩余没有发送出的iovec data,假如使用缓存
(利用StringFormatter::Put()),则这些数据将在下次WriteV时首先发送给client */
// We need to determine now whether to copy the remaining unsent
// iovec data into the buffer. This is determined based on
// the inSendType parameter passed in.
/* case 1:当发送类型是kDontBuffer,不缓存remaining unsent iovec data */
if (inSendType == kDontBuffer)
return theErr;
/* case 2:当发送类型是kAllOrNothing,且还有数据待发送时,返回EAGAIN */
/* If no data could be sent, return EWOULDBLOCK. Otherwise,buffer any unsent data. */
if ((inSendType == kAllOrNothing) && (theLengthSent == 0))
return EAGAIN;
/* case 3:当发送类型是kAlwaysBuffer,先确定未发送数据长度,再缓存remaining unsent iovec data */
// Some or none of the iovec data was sent. Copy the remainder into the output
// buffer.
/* 注意这是下面一段的思路 */
// The caller should consider this data sent.
/* 一定要使所有的inVec[]中的数据(长度为inTotalLength)全部发送出 */
if (outLengthSent != NULL)
*outLengthSent = inTotalLength;
/* 跳过那些已经送出的数据,更新还要送出数据的量theLengthSent,它已不足某个索引curVec的iov的长度 */
/* 注意这里的取值是1,没从0开始,因为它已经读了 */
UInt32 curVec = 1;
while (theLengthSent >= inVec[curVec].iov_len)
{
// Skip over the vectors that were in fact sent.
Assert(curVec < inNumVectors);
theLengthSent -= inVec[curVec].iov_len;
curVec++;
}
/* 将剩下的不够一个inVec[curVec].iov_len长度的数据(实际大小为inVec[curVec].iov_len - theLengthSent)放入指定缓存,并更新相关量 */
while (curVec < inNumVectors)
{
// Copy the remaining vectors into the buffer
this->Put( ((char*)inVec[curVec].iov_base) + theLengthSent,
inVec[curVec].iov_len - theLengthSent);
theLengthSent = 0;//以后的iovec都放入整个长度
curVec++;
}
return QTSS_NoErr;
}
/* 从RTSP Request stream中获取full RTSP Request Header,打印fRequest相关信息,解析得到它的尾部,并配置相应数据成员的值 */
QTSS_Error RTSPRequestStream::ReadRequest()
{
while (true)
{
/* 注意这个量非常重要 */
UInt32 newOffset = 0;
//If this is the case, we already HAVE a request on this session, and we now are done
//with the request and want to move onto the next one. The first thing we should do
//is check whether there is any lingering(延迟的) data in the stream. If there is, the parent
//session believes that is part of a new request
if (fRequestPtr != NULL)
{
/* 标记不再有complete RTSP client Request */
fRequestPtr = NULL;//flag that we no longer have a complete request
// Take all the retreated leftover(剩余的) data and move it to the beginning of the buffer
if ((fRetreatBytes > 0) && (fRequest.Len > 0))
::memmove(fRequest.Ptr, fRequest.Ptr + fRequest.Len + fRetreatBytesRead/* NOTE! */, fRetreatBytes);
// if we are decoding, we need to also move over the remaining encoded bytes
// to the right position in the fRequestBuffer
if (fEncodedBytesRemaining > 0)
{
/* 参见RTSPRequestStream::DecodeIncomingData() */
//Assert(fEncodedBytesRemaining < 4);
// The right position is at fRetreatBytes offset in the request buffer. The reason for this is:
// 1) We need to find a place in the request buffer where we know we have enough space to store
// fEncodedBytesRemaining. fRetreatBytes + fEncodedBytesRemaining will always be less than
// kRequestBufferSize because all this data must have been in the same request buffer, together, at one point.
//
// 2) We need to make sure that there is always more data in the RequestBuffer than in the decoded
// request buffer, otherwise we could overrun(超出限度) the decoded request buffer (we bounds check on the encoded
// buffer, not the decoded buffer). Leaving fRetreatBytes as empty space in the request buffer ensures
// that this principle is maintained.
::memmove(&fRequestBuffer[fRetreatBytes], &fRequestBuffer[fCurOffset - fEncodedBytesRemaining], fEncodedBytesRemaining);
fCurOffset = fRetreatBytes + fEncodedBytesRemaining;
Assert(fCurOffset < kRequestBufferSizeInBytes);
}
else
fCurOffset = fRetreatBytes;
newOffset = fRequest.Len = fRetreatBytes;
/* 因为已将Retreat data移位了 */
fRetreatBytes = fRetreatBytesRead = 0;
}
// We don't have any new data, so try and get some
/* 以下操作是确保newOffset>0 */
if (newOffset == 0)
{
if (fRetreatBytes > 0)
{
// This will be true if we've just snarfed(复制) another input stream, in which case the encoded data
// is copied into our request buffer, and its length is tracked(追踪) in fRetreatBytes.
// If this is true, just fall through(进行下去) and decode the data.
newOffset = fRetreatBytes;
fRetreatBytes = 0;
Assert(fEncodedBytesRemaining == 0);
}
else
{
// We don't have any new data, get some from the socket...
/* 利用TCPSocket的::recv()来接收数据,第一,二个参数是缓存地址和长度,第三个参数是接收数据的长度 */
QTSS_Error sockErr = fSocket->Read(&fRequestBuffer[fCurOffset],
(kRequestBufferSizeInBytes - fCurOffset) - 1, &newOffset);
//assume the client is dead if we get an error back
/* 目前缓冲区无数据可读 */
/* 当recv系统调用返回这个值时表示recv读数据时，对方没有发送数据过来。 */
if (sockErr == EAGAIN)
return QTSS_NoErr;
/* 假如返回出错,一定是连接断开 */
if (sockErr != QTSS_NoErr)
{
Assert(!fSocket->IsConnected());
return sockErr;
}
}
/* 当要base64 decode时 */
if (fDecode)
{
// If we need to decode this data, do it now.
/* 确保数据偏移量大于内存中需要decode的数据 */
Assert(fCurOffset >= fEncodedBytesRemaining);
/* 解密读进来的数据 */
QTSS_Error decodeErr = this->DecodeIncomingData(&fRequestBuffer[fCurOffset - fEncodedBytesRemaining],
newOffset + fEncodedBytesRemaining);
// If the above function returns an error, it is because we've
// encountered some non-base64 data in the stream. We can process
// everything up until that point, but all data after this point will
// be ignored.
/* 解码成功时,确保最后剩下的未解码的数据少于4个字节,参见下面的RTSPRequestStream::DecodeIncomingData() */
if (decodeErr == QTSS_NoErr)
Assert(fEncodedBytesRemaining < 4);
}
else
fRequest.Len += newOffset;
Assert(fRequest.Len < kRequestBufferSizeInBytes);
fCurOffset += newOffset;
}
/* 最后一定要达到这个结论! */
Assert(newOffset > 0);
// See if this is an interleaved data packet
/* 查找data packet,配置fIsDataPacket的值 */
/* 找到data packet */
if ('$' == *(fRequest.Ptr))
{
if (fRequest.Len < 4)
continue;
UInt16* dataLenP = (UInt16*)fRequest.Ptr;
/* 获取混叠包长度 */
UInt32 interleavedPacketLen = ntohs(dataLenP[1]) + 4;
if (interleavedPacketLen > fRequest.Len)
continue;
//put back any data that is not part of the header
/* 将不是header部分的数据放回失控数据处 */
fRetreatBytes += fRequest.Len - interleavedPacketLen;
fRequest.Len = interleavedPacketLen;
fRequestPtr = &fRequest;
fIsDataPacket = true;
return QTSS_RequestArrived;
}
fIsDataPacket = false;
/* 当打印RTSP info时,打印出如下信息:
(空两行)
#C->S;
#time: ms=*** data=Mon,29 July 2009 15:17:17 GTM
#server: ip=172.16.32.37 port=***
或#server: ip=NULL port=***
#client: ip=172.16.39.30 port=***
或#client: ip=NULL port=***
*********fRequest info***************
*/
if (fPrintRTSP)
{
/* 类似RTSPResponseStream::WriteV() */
/* 得到当前的GTM时间,格式为"Mon, 04 Nov 1996 21:42:17 GMT" */
DateBuffer theDate;
DateTranslator::UpdateDateBuffer(&theDate, 0); // get the current GMT date and time
/* OS::StartTimeMilli_Int()表示服务器运行多长时间? */
qtss_printf("\n\n#C->S:\n#time: ms=%lu date=%s\n", (UInt32) OS::StartTimeMilli_Int(), theDate.GetDateBuffer());
/* 假如有TCPSocket存在,就获取并打印其相关信息 */
if (fSocket != NULL)
{
UInt16 serverPort = fSocket->GetLocalPort();
UInt16 clientPort = fSocket->GetRemotePort();
StrPtrLen* theLocalAddrStr = fSocket->GetLocalAddrStr();
StrPtrLen* theRemoteAddrStr = fSocket->GetRemoteAddrStr();
if (theLocalAddrStr != NULL)
{ qtss_printf("#server: ip="); theLocalAddrStr->PrintStr(); qtss_printf(" port=%u\n" , serverPort );
}
else
{ qtss_printf("#server: ip=NULL port=%u\n" , serverPort );
}
if (theRemoteAddrStr != NULL)
{ qtss_printf("#client: ip="); theRemoteAddrStr->PrintStr(); qtss_printf(" port=%u\n" , clientPort );
}
else
{ qtss_printf("#client: ip=NULL port=%u\n" , clientPort );
}
}
/* 打印fRequest字符串 */
StrPtrLen str(fRequest);
str.PrintStrEOL("\n\r\n", "\n");// print the request but stop on \n\r\n and add a \n afterwards.
}
//use a StringParser object to search for a double EOL, which signifies the end of
//the header.
/* 下面要查找client发出的RTSP Request Header的末尾处 */
/* 找到fRequest末端了吗? */
Bool16 weAreDone = false;
StringParser headerParser(&fRequest);
UInt16 lcount = 0;
/* 当遇到eol时,fStartGet指针越过它 */
while (headerParser.GetThruEOL(NULL))
{
lcount++;
/* 当当前的fStartGet指针指向EOL时 */
if (headerParser.ExpectEOL())
{
//The legal end-of-header sequences are \r\r, \r\n\r\n, & \n\n. NOT \r\n\r!
//If the packets arrive just a certain way, we could get here with the latter
//combo(组合,即\r\n\r), and not wait for a final \n.
/* 假如查找到"\r\n\r",就继续查找,直至找到符合条件的末端 */
if ((headerParser.GetDataParsedLen() > 2) &&
(memcmp(headerParser.GetCurrentPosition() - 3, "\r\n\r", 3) == 0))
continue;
/* 标记找到了 */
weAreDone = true;
break;
}
/* 假如是"xxxxxx\r" */
else if (lcount == 1) {
// if this request is actually a ShoutCast password it will be
// in the form of "xxxxxx\r" where "xxxxx" is the password.
// If we get a 1st request line ending in \r with no blanks we will
// assume that this is the end of the request.
UInt16 flag = 0;
UInt16 i = 0;
/* 检查"xxxxxx\r"中有无空格?没有就说明我们找到了 */
for (i=0; i<fRequest.Len; i++)
{
if (fRequest.Ptr[i] == ' ')
flag++;
}
if (flag == 0)
{
weAreDone = true;
break;
}
}
}
//weAreDone means we have gotten a full request
/* 我们找到了一个Full RTSP Request Header? */
if (weAreDone)
{
//put back any data that is not part of the header
fRequest.Len -= headerParser.GetDataRemaining();
fRetreatBytes += headerParser.GetDataRemaining();
fRequestPtr = &fRequest;
return QTSS_RequestArrived;
}
//check for a full buffer
/* 当到达Request buffer末端时,给出提示信息E2BIG */
if (fCurOffset == kRequestBufferSizeInBytes - 1)
{
fRequestPtr = &fRequest;
return E2BIG;
}
}
}
