transmission/libtransmission/fdlimit.h

100 lines
3.7 KiB
C

/******************************************************************************
* $Id$
*
* Copyright (c) 2005-2008 Transmission authors and contributors
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*****************************************************************************/
#include "net.h"
/***********************************************************************
* tr_fdInit
***********************************************************************
* Detect the maximum number of open files and initializes things.
**********************************************************************/
void tr_fdInit( int globalPeerLimit );
void tr_fdClose( void );
/**
* Returns an fd to the specified filename.
*
* A small pool of open files is kept to avoid the overhead of
* continually opening and closing the same files when downloading
* piece data. It's also used to ensure only one caller can
* write to the file at a time. Callers check out a file, use it,
* and then check it back in via tr_fdFileReturn() when done.
*
* - if `folder' doesn't exist, TR_ERROR_IO_PARENT is returned.
* - if doWrite is true, subfolders in torrentFile are created if necessary.
* - if doWrite is true, the target file is created if necessary.
*
* on success, a file descriptor >= 0 is returned.
* on failure, a negative number corresponding to tr_errno is returned.
*
* @see tr_fdFileReturn
* @see tr_fdFileClose
* @see tr_errno
*/
int tr_fdFileCheckout( const char * folder,
const char * torrentFile,
int doWrite );
/**
* Returns an fd from tr_fdFileCheckout() so that other clients may borrow it.
*
* @see tr_fdFileCheckout
* @see tr_fdFileClose
*/
void tr_fdFileReturn( int file );
/**
* Closes a file that's being held by our file repository.
*
* If the file isn't checked out, it's closed immediately.
* If the file is currently checked out, it will be closed upon its return.
*
* @see tr_fdFileCheckout
* @see tr_fdFileReturn
*/
void tr_fdFileClose( const char * filename );
/***********************************************************************
* Sockets
**********************************************************************/
int tr_fdSocketCreate( int type, int priority );
int tr_fdSocketAccept( int b, struct in_addr * addr, tr_port_t * port );
void tr_fdSocketClose( int s );
/***********************************************************************
* tr_fdClose
***********************************************************************
* Frees resources allocated by tr_fdInit.
**********************************************************************/
void tr_fdClose( void );
void tr_fdSetPeerLimit( uint16_t n );
uint16_t tr_fdGetPeerLimit( void );