transmission/libtransmission/peer-io.h

/*
 * This file Copyright (C) 2007-2008 Charles Kerr <charles@transmissionbt.com>
 *
 * This file is licensed by the GPL version 2.  Works owned by the
 * Transmission project are granted a special exemption to clause 2(b)
 * so that the bulk of its code can remain under the MIT license.
 * This exemption does not extend to derived works not owned by
 * the Transmission project.
 *
 * $Id$
 */

#ifndef __TRANSMISSION__
#error only libtransmission should #include this header.
#endif

#ifndef TR_PEER_IO_H
#define TR_PEER_IO_H

/**
***
**/

#include <assert.h>

#include <event.h>

#include "transmission.h"
#include "list.h" /* __tr_list */
#include "net.h" /* tr_address */

struct evbuffer;
struct tr_bandwidth;
struct tr_crypto;
struct tr_peerIo;

typedef enum
{
    READ_NOW,
    READ_LATER,
    READ_ERR
}
ReadState;

typedef ReadState ( *tr_can_read_cb  )( struct tr_peerIo * io,
                                        void             * user_data,
                                        size_t           * setme_piece_byte_count );

typedef void      ( *tr_did_write_cb )( struct tr_peerIo * io,
                                        size_t             bytesWritten,
                                        int                wasPieceData,
                                        void             * userData );

typedef void      ( *tr_net_error_cb )( struct tr_peerIo * io,
                                        short              what,
                                        void             * userData );

typedef struct tr_peerIo
{
    tr_bool            isEncrypted;
    tr_bool            isIncoming;
    tr_bool            peerIdIsSet;
    tr_bool            extendedProtocolSupported;
    tr_bool            fastExtensionSupported;

    int                magicNumber;

    uint8_t            encryptionMode;
    tr_port            port;
    int                socket;

    uint8_t            peerId[SHA_DIGEST_LENGTH];
    time_t             timeCreated;

    tr_session       * session;

    tr_address         addr;

    tr_can_read_cb     canRead;
    tr_did_write_cb    didWrite;
    tr_net_error_cb    gotError;
    void *             userData;

    struct tr_bandwidth * bandwidth;
    struct tr_crypto    * crypto;

    struct evbuffer  * inbuf;
    struct evbuffer  * outbuf;
    struct __tr_list   outbuf_datatypes; /* struct tr_datatype */

    struct event       event_read;
    struct event       event_write;
}
tr_peerIo;

/**
***
**/

tr_peerIo*  tr_peerIoNewOutgoing( tr_session              * session,
                                  const struct tr_address * addr,
                                  tr_port                   port,
                                  const  uint8_t          * torrentHash );

tr_peerIo*  tr_peerIoNewIncoming( tr_session              * session,
                                  const struct tr_address * addr,
                                  tr_port                   port,
                                  int                       socket );

void        tr_peerIoFree       ( tr_peerIo               * io );

tr_bool     tr_isPeerIo         ( const tr_peerIo         * io );


/**
***
**/

void        tr_peerIoEnableLTEP( tr_peerIo * io, tr_bool flag );

tr_bool     tr_peerIoSupportsLTEP( const tr_peerIo * io );

void        tr_peerIoEnableFEXT( tr_peerIo * io, tr_bool flag );

tr_bool     tr_peerIoSupportsFEXT( const tr_peerIo * io );

/**
***
**/

tr_session* tr_peerIoGetSession ( tr_peerIo * io );

const char* tr_peerIoAddrStr( const struct tr_address * addr,
                              tr_port                   port );

const char* tr_peerIoGetAddrStr( const tr_peerIo * io );

const struct tr_address * tr_peerIoGetAddress( const tr_peerIo * io,
                                               tr_port         * port );

const uint8_t*       tr_peerIoGetTorrentHash( tr_peerIo * io );

int                  tr_peerIoHasTorrentHash( const tr_peerIo * io );

void                 tr_peerIoSetTorrentHash( tr_peerIo *     io,
                                              const uint8_t * hash );

int                  tr_peerIoReconnect( tr_peerIo * io );

tr_bool              tr_peerIoIsIncoming( const tr_peerIo * io );

static inline int    tr_peerIoGetAge( const tr_peerIo * io )
{
    return time( NULL ) - io->timeCreated;
}


/**
***
**/

void                 tr_peerIoSetPeersId( tr_peerIo *     io,
                                          const uint8_t * peer_id );

const uint8_t*       tr_peerIoGetPeersId( const tr_peerIo * io );

/**
***
**/

void    tr_peerIoSetIOFuncs      ( tr_peerIo        * io,
                                   tr_can_read_cb     readcb,
                                   tr_did_write_cb    writecb,
                                   tr_net_error_cb    errcb,
                                   void             * user_data );

/**
***
**/

void    tr_peerIoWrite          ( tr_peerIo         * io,
                                  const void        * writeme,
                                  size_t              writemeLen,
                                  int                 isPieceData );

void    tr_peerIoWriteBuf       ( tr_peerIo         * io,
                                  struct evbuffer   * buf,
                                  int                 isPieceData );

/**
***
**/

struct tr_crypto* tr_peerIoGetCrypto( tr_peerIo * io );

typedef enum
{
    /* these match the values in MSE's crypto_select */
    PEER_ENCRYPTION_NONE  = ( 1 << 0 ),
    PEER_ENCRYPTION_RC4   = ( 1 << 1 )
}
EncryptionMode;

void      tr_peerIoSetEncryption( tr_peerIo * io,
                                  int         encryptionMode );

int       tr_peerIoIsEncrypted( const tr_peerIo * io );

void      tr_peerIoWriteBytes( tr_peerIo *       io,
                               struct evbuffer * outbuf,
                               const void *      bytes,
                               size_t            byteCount );

static inline void  tr_peerIoWriteUint8( tr_peerIo *       io,
                                         struct evbuffer * outbuf,
                                         uint8_t           writeme )
{
    tr_peerIoWriteBytes( io, outbuf, &writeme, sizeof( uint8_t ) );
}

static inline void tr_peerIoWriteUint16( tr_peerIo *       io,
                                         struct evbuffer * outbuf,
                                         uint16_t          writeme )
{
    const uint16_t tmp = htons( writeme );
    tr_peerIoWriteBytes( io, outbuf, &tmp, sizeof( uint16_t ) );
}

static inline void tr_peerIoWriteUint32( tr_peerIo *       io,
                                         struct evbuffer * outbuf,
                                         uint32_t          writeme )
{
    const uint32_t tmp = htonl( writeme );
    tr_peerIoWriteBytes( io, outbuf, &tmp, sizeof( uint32_t ) );
}

void      tr_peerIoReadBytes( tr_peerIo *       io,
                              struct evbuffer * inbuf,
                              void *            bytes,
                              size_t            byteCount );

static inline void tr_peerIoReadUint8( tr_peerIo *       io,
                                       struct evbuffer * inbuf,
                                       uint8_t *         setme )
{
    tr_peerIoReadBytes( io, inbuf, setme, sizeof( uint8_t ) );
}

static inline void tr_peerIoReadUint16( tr_peerIo *       io,
                                        struct evbuffer * inbuf,
                                        uint16_t *        setme )
{
    uint16_t tmp;
    tr_peerIoReadBytes( io, inbuf, &tmp, sizeof( uint16_t ) );
    *setme = ntohs( tmp );
}

static inline void tr_peerIoReadUint32( tr_peerIo *       io,
                                        struct evbuffer * inbuf,
                                        uint32_t *        setme )
{
    uint32_t tmp;
    tr_peerIoReadBytes( io, inbuf, &tmp, sizeof( uint32_t ) );
    *setme = ntohl( tmp );
}

void      tr_peerIoDrain( tr_peerIo *       io,
                          struct evbuffer * inbuf,
                          size_t            byteCount );

/**
***
**/

size_t    tr_peerIoGetWriteBufferSpace( const tr_peerIo * io );

void      tr_peerIoSetBandwidth( tr_peerIo            * io,
                                 struct tr_bandwidth  * bandwidth );

void      tr_peerIoBandwidthUsed( tr_peerIo           * io,
                                  tr_direction          direction,
                                  size_t                byteCount,
                                  int                   isPieceData );

tr_bool   tr_peerIoHasBandwidthLeft( const tr_peerIo  * io,
                                     tr_direction       dir );

/**
***
**/

void      tr_peerIoSetEnabled( tr_peerIo    * io,
                               tr_direction   dir,
                               tr_bool        isEnabled );
                       
int       tr_peerIoFlush( tr_peerIo     * io,
                          tr_direction    dir,
                          size_t          byteLimit );

/**
***
**/

static inline struct evbuffer * tr_peerIoGetReadBuffer( tr_peerIo * io )
{
    assert( tr_isPeerIo( io ) );

    return io->inbuf;
}


#endif