/*
 * This file Copyright (C) 2005-2014 Mnemosyne LLC
 *
 * It may be used under the GNU Public License v2 or v3 licenses,
 * or any future license endorsed by Mnemosyne LLC.
 *
 * $Id$
 */

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

#include "transmission.h"
#include "net.h"

/**
 * @addtogroup file_io File IO
 * @{
 */

/***
****
***/

void tr_set_file_for_single_pass (int fd);

int tr_open_file_for_scanning (const char * filename);

int tr_open_file_for_writing (const char * filename);

void tr_close_file (int fd);

int tr_fsync (int fd);

ssize_t tr_pread (int fd, void *buf, size_t count, off_t offset);
ssize_t tr_pwrite (int fd, const void *buf, size_t count, off_t offset);
int tr_prefetch (int fd, off_t offset, size_t count);


/**
 * 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.
 *
 * - if do_write is true, subfolders in torrentFile are created if necessary.
 * - if do_write is true, the target file is created if necessary.
 *
 * on success, a file descriptor >= 0 is returned.
 * on failure, a -1 is returned and errno is set.
 *
 * @see tr_fdFileClose
 */
int  tr_fdFileCheckout (tr_session             * session,
                        int                      torrent_id,
                        tr_file_index_t          file_num,
                        const char             * filename,
                        bool                     do_write,
                        tr_preallocation_mode    preallocation_mode,
                        uint64_t                 preallocation_file_size);

int tr_fdFileGetCached (tr_session             * session,
                        int                      torrent_id,
                        tr_file_index_t          file_num,
                        bool                  doWrite);

bool tr_fdFileGetCachedMTime (tr_session       * session,
                              int                torrent_id,
                              tr_file_index_t    file_num,
                              time_t           * mtime);


/**
 * Closes a file that's being held by our file repository.
 *
 * If the file isn't checked out, it's fsync ()ed and close ()d immediately.
 * If the file is currently checked out, it will be closed upon its return.
 *
 * @see tr_fdFileCheckout
 */
void tr_fdFileClose (tr_session        * session,
                     const tr_torrent  * tor,
                     tr_file_index_t     file_num);


/**
 * Closes all the files associated with a given torrent id
 */
void tr_fdTorrentClose (tr_session * session, int torrentId);


/***********************************************************************
 * Sockets
 **********************************************************************/
int      tr_fdSocketCreate (tr_session * session, int domain, int type);

int      tr_fdSocketAccept (tr_session  * session,
                            int           listening_sockfd,
                            tr_address  * addr,
                            tr_port     * port);

void     tr_fdSocketClose (tr_session * session, int s);

/***********************************************************************
 * tr_fdClose
 ***********************************************************************
 * Frees resources allocated by tr_fdInit.
 **********************************************************************/
void     tr_fdClose (tr_session * session);

/* @} */