khanat-code-old/code/nel/include/nel/net/message.h

334 lines
10 KiB
C++

// NeL - MMORPG Framework <http://dev.ryzom.com/projects/nel/>
// Copyright (C) 2010 Winch Gate Property Limited
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
#ifndef NL_MESSAGE_H
#define NL_MESSAGE_H
#include "nel/misc/types_nl.h"
#include "nel/misc/mem_stream.h"
#include <vector>
namespace NLNET
{
extern const char *LockedSubMessageError;
/**
* Message memory stream for network. Can be serialized to/from (see SerialBuffer()). Can be sent or received
* over a network, using the NeL network engine.
* If MESSAGES_PLAIN_TEXT is defined, the messages will be serialized to/from plain text (human-readable),
* instead of binary.
*
* \author Vianney Lecroart
* \author Nevrax France
* \date 2001
*/
class CMessage : public NLMISC::CMemStream
{
public:
enum TStreamFormat { UseDefault, Binary, String };
enum TMessageType { OneWay, Request, Response, Except};
struct TFormat
{
uint8 StringMode : 1, // true if the message body is string encoded, binary encoded if false otherwise
LongFormat : 1, // true if the message format is long (d'ho ? all message are long !?!, always true)
MessageType : 2; // type of the message (from TMessageType), classical message are 'OneWay'
TFormat()
{
StringMode = 0;
LongFormat = 0;
MessageType = 0;
}
void serial(NLMISC::IStream &s)
{
if (s.isReading())
{
// decode the bit field in a network independant manner
uint8 b;
s.serial(b);
LongFormat = b & 1;
StringMode = (b>>1) & 1;
MessageType = (b>>2) & 3;
}
else
{
// encode the bit field in a network independant manner
uint8 b = LongFormat | StringMode << 1 | MessageType << 2;
s.serial(b);
}
}
};
CMessage (const std::string &name = "", bool inputStream = false, TStreamFormat streamformat = UseDefault, uint32 defaultCapacity = 1000);
CMessage (NLMISC::CMemStream &memstr);
/// Copy constructor
CMessage (const CMessage &other);
/// Assignment operator
CMessage &operator= (const CMessage &other);
/// exchange memory data
void swap(CMessage &other);
/// Sets the message type as a string and put it in the buffer if we are in writing mode
void setType (const std::string &name, TMessageType type=OneWay);
void changeType (const std::string &name);
/// Returns the size, in byte of the header that contains the type name of the message or the type number
uint32 getHeaderSize () const;
/** The message was filled with an CMemStream, Now, we'll get the message type on this buffer.
* This method updates _LengthR with the actual size of the buffer (it calls resetLengthR()).
*/
void readType ();
/// Get the message name (input message only) and advance the current pos
std::string readTypeAtCurrentPos() const;
// Returns true if the message type was already set
bool typeIsSet () const;
/**
* Returns the length (size) of the message, in bytes.
* If isReading(), it is the number of bytes that can be read,
* otherwise it is the number of bytes that have been written.
* Overloaded because uses a specific version of lengthR().
*/
virtual uint32 length() const
{
if ( isReading() )
{
return lengthR();
}
else
{
return lengthS();
}
}
virtual uint32 lengthS() const
{
if (!hasLockedSubMessage())
// return _BufPos - _Buffer.getPtr();
return _Buffer.Pos;
else
// return (_BufPos - _Buffer.getPtr()) - _SubMessagePosR;
return _Buffer.Pos - _SubMessagePosR;
}
/// Returns the "read" message size (number of bytes to read) (note: see comment about _LengthR)
uint32 lengthR() const
{
return _LengthR;
}
virtual sint32 getPos () const throw(NLMISC::EStream)
{
// return (_BufPos - _Buffer.getPtr()) - _SubMessagePosR;
return _Buffer.Pos - _SubMessagePosR;
}
// virtual sint32 getPos() const
// {
// return (_BufPos - _Buffer.getPtr()) - _SubMessagePosR;
// }
/**
* Set an input message to look like, from a message callback's scope, as if it began at the current
* pos and ended at the current pos + msgSize, and read the header and return the name of the sub message.
*
* This method provides a way to pass a big message containing a set of sub messages to their message
* callback, without copying each sub message to a new message. If you need to perform some actions
* that are not allowed with a locked message (see postconditions), use assignFromSubMessage():
* the locked sub message in M1 can be copied to a new message M2 with 'M2.assignFromSubMessage( M1 )'.
*
* Preconditions:
* - The message is an input message (isReading())
* - msgEndPos <= length()
* - getPos() >= getHeaderSize()
*
* Postconditions:
* - The sub message is ready to be read from
* - length() returns the size of the sub message
* - getName() return the name of the sub message
* - Unless you call unlockSubMessage(), the following actions will assert or raise an exception:
* Serializing more than the sub message size, clear(), operator=() (from/to), invert().
*/
std::string lockSubMessage( uint32 subMsgSize ) const
{
nlassert(!hasLockedSubMessage());
uint32 subMsgBeginPos = getPos();
uint32 subMsgEndPos = subMsgBeginPos + subMsgSize;
nlassertex( isReading() && (subMsgEndPos <= lengthR()), ("%s %u %u", isReading()?"R":"W", subMsgEndPos, lengthR()) );
std::string name = unconst(*this).readTypeAtCurrentPos();
_SubMessagePosR = subMsgBeginPos;
// _LengthR = subMsgEndPos;
_LengthR = subMsgSize;
return name;
}
/**
* Exit from sub message locking, and skip the whole sub message.
*
* Preconditions:
* - The message is an input message (isReading()) and has been locked using lockSubMessage()
* - The reading pos is within or at the end of the previous sub message (if any) (see nlassertex)
*
* Postconditions:
* - The current pos is the next byte after the sub message
*/
void unlockSubMessage() const
{
nlassert( isReading() && hasLockedSubMessage() );
nlassertex( getPos() <= sint32(_SubMessagePosR+_LengthR), ("The callback for msg %s read more data than there is in the message (pos=%d len=%u)", getName().c_str(), getPos(), _LengthR) );
uint32 subMsgEndPos = _SubMessagePosR + _LengthR;
resetSubMessageInternals();
seek( subMsgEndPos, IStream::begin );
}
/// Return true if a sub message has been locked
bool hasLockedSubMessage() const
{
return (_SubMessagePosR != 0);
}
/** If a sub message is locked, return the sub message part
*/
virtual const uint8 *buffer() const
{
if (hasLockedSubMessage())
{
// return _Buffer.getPtr() + _SubMessagePosR;
return _Buffer.getBuffer().getPtr() + _SubMessagePosR;
}
else
return CMemStream::buffer();
}
/**
* Similar to operator=, but makes the current message contain *only* the locked sub message in msgin
* or the whole msgin if it is not locked
*
* Preconditions:
* - msgin is an input message (isReading())
* - The current message is blank (new or reset with clear())
*
* Postconditions:
* - If msgin has been locked using lockSubMessage(), the current message contains only the locked
* sub message in msgin, otherwise the current message is exactly msgin
* - The current message is an input message, it is not locked
*/
void assignFromSubMessage( const CMessage& msgin );
/**
* Transforms the message from input to output or from output to input
*/
void invert()
{
nlassertex( (!isReading()) || (!hasLockedSubMessage()), ("Inverting %s", LockedSubMessageError) );
CMemStream::invert();
if ( isReading() )
{
// Write -> Read: skip the header
_TypeSet = false;
// if ( _Buffer.size() != 0 )
if ( _Buffer.getBuffer().size() != 0 )
readType();
}
// For Read -> Write, please use clear()
}
// Clear the message. With this function, you can reuse a message to create another message
void clear ();
/** Returns the type name in string if available. Be sure that the message have the name of the message type
* In a callback driven by message name, getName() does not necessarily return the right name.
*/
std::string getName () const;
/** Return the type of the message.
*/
TMessageType getType() const;
/** Returns a readable string to display it to the screen. It's only for debugging purpose!
* Don't use it for anything else than to debugging, the string format could change in the future.
* \param hexFormat If true, display all bytes in hexadecimal
* \param textFormat If true, display all bytes as chars (above 31, otherwise '.')
*/
std::string toString ( bool hexFormat=false, bool textFormat=false ) const;
/// Set default stream mode
static void setDefaultStringMode( bool stringmode ) { _DefaultStringMode = stringmode; }
/// Return an input stream containing the stream beginning in the message at the specified pos
NLMISC::CMemStream extractStreamFromPos( sint32 pos );
/// Encapsulate/decapsulate another message inside the current message
void serialMessage( CMessage& msg );
protected:
/// Utility method
void init( const std::string &name, TStreamFormat streamformat );
/// Utility method
void resetSubMessageInternals() const
{
_SubMessagePosR = 0;
// _LengthR = _Buffer.size();
_LengthR = _Buffer.getBuffer().size();
}
private:
std::string _Name;
mutable TMessageType _Type;
// When sub message lock mode is enabled, beginning position of sub message to read (before header)
mutable uint32 _SubMessagePosR;
// Length (can be smaller than _Buffer.size() if limitLength() is used) (updated in reading mode only)
mutable uint32 _LengthR;
// Size of the header (that contains the name type or number type)
uint32 _HeaderSize;
bool _TypeSet;
// Default stream format
static bool _DefaultStringMode;
};
}
#endif // NL_MESSAGE_H
/* End of message.h */