ReadCallback Class Reference

#include <AsyncSocketTest.h>

Inheritance diagram for ReadCallback:

Classes
class	Buffer

Public Member Functions
	ReadCallback (size_t _maxBufferSz=4096)
	~ReadCallback () override
void	getReadBuffer (void **bufReturn, size_t *lenReturn) override
void	readDataAvailable (size_t len) noexceptoverride
void	readEOF () noexceptoverride
void	readErr (const folly::AsyncSocketException &ex) noexceptoverride
void	verifyData (const char *expected, size_t expectedLen) const
size_t	dataRead () const
Public Member Functions inherited from folly::AsyncReader::ReadCallback
virtual bool	isBufferMovable () noexcept
virtual size_t	maxBufferSize () const
virtual void	readBufferAvailable (std::unique_ptr< IOBuf >) noexcept

Public Attributes
StateEnum	state
folly::AsyncSocketException	exception
std::vector< Buffer >	buffers
Buffer	currentBuffer
VoidCallback	dataAvailableCallback
const size_t	maxBufferSz

Detailed Description

Definition at line 88 of file AsyncSocketTest.h.

Constructor & Destructor Documentation

ReadCallback::ReadCallback ( size_t  _maxBufferSz = 4096 )

inlineexplicit

Definition at line 90 of file AsyncSocketTest.h.

      : state(STATE_WAITING),
        exception(folly::AsyncSocketException::UNKNOWN, "none"),
        buffers(),
        maxBufferSz(_maxBufferSz) {}

ReadCallback::~ReadCallback ( )

inlineoverridevirtual

Reimplemented from folly::AsyncReader::ReadCallback.

Definition at line 96 of file AsyncSocketTest.h.

                           {
    for (std::vector<Buffer>::iterator it = buffers.begin();
         it != buffers.end();
         ++it) {
      it->free();
    }
    currentBuffer.free();
  }

Member Function Documentation

size_t ReadCallback::dataRead ( ) const

inline

Definition at line 143 of file AsyncSocketTest.h.

                          {
    size_t ret = 0;
    for (const auto& buf : buffers) {
      ret += buf.length;
    }
    return ret;
  }

void ReadCallback::getReadBuffer ( void **  bufReturn, size_t *  lenReturn  )

inlineoverridevirtual

When data becomes available, getReadBuffer() will be invoked to get the buffer into which data should be read.

This method allows the ReadCallback to delay buffer allocation until data becomes available. This allows applications to manage large numbers of idle connections, without having to maintain a separate read buffer for each idle connection.

It is possible that in some cases, getReadBuffer() may be called multiple times before readDataAvailable() is invoked. In this case, the data will be written to the buffer returned from the most recent call to readDataAvailable(). If the previous calls to readDataAvailable() returned different buffers, the ReadCallback is responsible for ensuring that they are not leaked.

If getReadBuffer() throws an exception, returns a nullptr buffer, or returns a 0 length, the ReadCallback will be uninstalled and its readError() method will be invoked.

getReadBuffer() is not allowed to change the transport state before it returns. (For example, it should never uninstall the read callback, or set a different read callback.)

Parameters

bufReturn	getReadBuffer() should update *bufReturn to contain the address of the read buffer. This parameter will never be nullptr.
lenReturn	getReadBuffer() should update *lenReturn to contain the maximum number of bytes that may be written to the read buffer. This parameter will never be nullptr.

Implements folly::AsyncReader::ReadCallback.

Definition at line 105 of file AsyncSocketTest.h.

                                                                   {
    if (!currentBuffer.buffer) {
      currentBuffer.allocate(maxBufferSz);
    }
    *bufReturn = currentBuffer.buffer;
    *lenReturn = currentBuffer.length;
  }

void ReadCallback::readDataAvailable ( size_t  len )

inlineoverridevirtualnoexcept

readDataAvailable() will be invoked when data has been successfully read into the buffer returned by the last call to getReadBuffer().

The read callback remains installed after readDataAvailable() returns. It must be explicitly uninstalled to stop receiving read events. getReadBuffer() will be called at least once before each call to readDataAvailable(). getReadBuffer() will also be called before any call to readEOF().

Parameters

len	The number of bytes placed in the buffer.

Implements folly::AsyncReader::ReadCallback.

Definition at line 113 of file AsyncSocketTest.h.

                                                       {
    currentBuffer.length = len;
    buffers.push_back(currentBuffer);
    currentBuffer.reset();
    if (dataAvailableCallback) {
      dataAvailableCallback();
    }
  }

void ReadCallback::readEOF ( )

inlineoverridevirtualnoexcept

readEOF() will be invoked when the transport is closed.

The read callback will be automatically uninstalled immediately before readEOF() is invoked.

Implements folly::AsyncReader::ReadCallback.

Definition at line 122 of file AsyncSocketTest.h.

References STATE_SUCCEEDED.

                                   {
    state = STATE_SUCCEEDED;
  }

void ReadCallback::readErr ( const folly::AsyncSocketException &  ex )

inlineoverridevirtualnoexcept

readError() will be invoked if an error occurs reading from the transport.

The read callback will be automatically uninstalled immediately before readError() is invoked.

Parameters

ex	An exception describing the error that occurred.

Implements folly::AsyncReader::ReadCallback.

Definition at line 126 of file AsyncSocketTest.h.

References ConnCallback::exception, and STATE_FAILED.

                                                                      {
    state = STATE_FAILED;
    exception = ex;
  }

void ReadCallback::verifyData ( const char *  expected, size_t  expectedLen  ) const

inline

Definition at line 131 of file AsyncSocketTest.h.

References min.

                                                                  {
    size_t offset = 0;
    for (size_t idx = 0; idx < buffers.size(); ++idx) {
      const auto& buf = buffers[idx];
      size_t cmpLen = std::min(buf.length, expectedLen - offset);
      CHECK_EQ(memcmp(buf.buffer, expected + offset, cmpLen), 0);
      CHECK_EQ(cmpLen, buf.length);
      offset += cmpLen;
    }
    CHECK_EQ(offset, expectedLen);
  }

Member Data Documentation

std::vector<Buffer> ReadCallback::buffers

Definition at line 176 of file AsyncSocketTest.h.

Buffer ReadCallback::currentBuffer

Definition at line 177 of file AsyncSocketTest.h.

VoidCallback ReadCallback::dataAvailableCallback

Definition at line 178 of file AsyncSocketTest.h.

folly::AsyncSocketException ReadCallback::exception

Definition at line 175 of file AsyncSocketTest.h.

const size_t ReadCallback::maxBufferSz

Definition at line 179 of file AsyncSocketTest.h.

StateEnum ReadCallback::state

Definition at line 174 of file AsyncSocketTest.h.

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The documentation for this class was generated from the following file:

• proxygen/folly/folly/io/async/test/AsyncSocketTest.h