Added a way for partial sends over non-blocking TcpSockets to be handled properly.

This commit is contained in:
binary1248 2015-02-06 19:37:53 +01:00 committed by Lukas Dürrenberger
parent 67c7663c80
commit d790114df8
5 changed files with 66 additions and 9 deletions

View File

@ -282,6 +282,7 @@ private:
////////////////////////////////////////////////////////////
std::vector<char> m_data; ///< Data stored in the packet
std::size_t m_readPos; ///< Current reading position in the packet
std::size_t m_sendPos; ///< Current send position in the packet (for handling partial sends)
bool m_isValid; ///< Reading state of the packet
};

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@ -54,6 +54,7 @@ public:
{
Done, ///< The socket has sent / received the data
NotReady, ///< The socket is not ready to send / receive data yet
Partial, ///< The socket sent a part of the data
Disconnected, ///< The TCP socket has been disconnected
Error ///< An unexpected error happened
};

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@ -124,6 +124,9 @@ public:
////////////////////////////////////////////////////////////
/// \brief Send raw data to the remote peer
///
/// To be able to handle partial sends over non-blocking
/// sockets, use the send(const void*, std::size_t, std::size_t&)
/// overload instead.
/// This function will fail if the socket is not connected.
///
/// \param data Pointer to the sequence of bytes to send
@ -136,6 +139,22 @@ public:
////////////////////////////////////////////////////////////
Status send(const void* data, std::size_t size);
////////////////////////////////////////////////////////////
/// \brief Send raw data to the remote peer
///
/// This function will fail if the socket is not connected.
///
/// \param data Pointer to the sequence of bytes to send
/// \param size Number of bytes to send
/// \param sent The number of bytes sent will be written here
///
/// \return Status code
///
/// \see receive
///
////////////////////////////////////////////////////////////
Status send(const void* data, std::size_t size, std::size_t& sent);
////////////////////////////////////////////////////////////
/// \brief Receive raw data from the remote peer
///
@ -157,6 +176,10 @@ public:
////////////////////////////////////////////////////////////
/// \brief Send a formatted packet of data to the remote peer
///
/// In non-blocking mode, if this function returns sf::Socket::Partial,
/// you \em must retry sending the same unmodified packet before sending
/// anything else in order to guarantee the packet arrives at the remote
/// peer uncorrupted.
/// This function will fail if the socket is not connected.
///
/// \param packet Packet to send

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@ -37,6 +37,7 @@ namespace sf
////////////////////////////////////////////////////////////
Packet::Packet() :
m_readPos(0),
m_sendPos(0),
m_isValid(true)
{

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@ -218,6 +218,18 @@ void TcpSocket::disconnect()
////////////////////////////////////////////////////////////
Socket::Status TcpSocket::send(const void* data, std::size_t size)
{
if (!isBlocking())
err() << "Warning: Partial sends might not be handled properly." << std::endl;
std::size_t sent;
return send(data, size, sent);
}
////////////////////////////////////////////////////////////
Socket::Status TcpSocket::send(const void* data, std::size_t size, std::size_t& sent)
{
// Check the parameters
if (!data || (size == 0))
@ -227,16 +239,22 @@ Socket::Status TcpSocket::send(const void* data, std::size_t size)
}
// Loop until every byte has been sent
int sent = 0;
int sizeToSend = static_cast<int>(size);
for (int length = 0; length < sizeToSend; length += sent)
int result = 0;
for (sent = 0; sent < size; sent += result)
{
// Send a chunk of data
sent = ::send(getHandle(), static_cast<const char*>(data) + length, sizeToSend - length, flags);
result = ::send(getHandle(), static_cast<const char*>(data) + sent, size - sent, flags);
// Check for errors
if (sent < 0)
return priv::SocketImpl::getErrorStatus();
if (result < 0)
{
Status status = priv::SocketImpl::getErrorStatus();
if ((status == NotReady) && sent)
return Partial;
return status;
}
}
return Done;
@ -294,17 +312,30 @@ Socket::Status TcpSocket::send(Packet& packet)
// First convert the packet size to network byte order
Uint32 packetSize = htonl(static_cast<Uint32>(size));
// Allocate memory for the data block to send
std::vector<char> blockToSend(sizeof(packetSize) + size);
// Copy the packet size and data into the block to send
std::memcpy(&blockToSend[0], &packetSize, sizeof(packetSize));
if (size > 0)
std::memcpy(&blockToSend[0] + sizeof(packetSize), data, size);
// Send the data block
return send(&blockToSend[0], blockToSend.size());
std::size_t sent;
Status status = send(&blockToSend[0] + packet.m_sendPos, blockToSend.size() - packet.m_sendPos, sent);
// In the case of a partial send, record the location to resume from
if (status == Partial)
{
packet.m_sendPos += sent;
}
else if (status == Done)
{
packet.m_sendPos = 0;
}
return status;
}