giftstate.c

Last change: 2008-02-03 This is the source code of KCeasy。

/*****************************************************************************
 * giftstate.c: file input from giFT state files (file: access plug-in)
 *****************************************************************************
 * Copyright (C) 2001, 2002 VideoLAN
 * $Id: giftstate.c,v 1.5 2004/08/06 09:47:48 mkern Exp $
 *
 * Authors: Christophe Massiot <[e-mail]>
 *          Markus Kern <[e-mail]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/


/*****************************************************************************
 * VLC's file access plugin modified for use on giFT state files.
 * Specifically allowing accesing the file while giFT is writing to it.
 * Actual chunk recognition is not implemented at this time.
 * 
 * Theory of operation:
 *   - If windows NT use FILE_SHARE_DELETE so giFT is able to move the file on
 *     completion. Windows will delete the old one automatically when all file
 *     handles are closed.
 *   - If we don't have FILE_SHARE_DELETE open the file normally. giFT will
 *     copy the file on completion and the unlinking will fail. When we are
 *     finished with playback and the state file is gone we delete the media
 *     file.
 *
 *****************************************************************************/


/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <vlc/vlc.h>
#include <vlc/input.h>

#include <stdlib.h>
#include <string.h>
#ifdef HAVE_SYS_TYPES_H
#   include <sys/types.h>
#endif
#ifdef HAVE_SYS_TIME_H
#   include <sys/time.h>
#endif
#ifdef HAVE_SYS_STAT_H
#   include <sys/stat.h>
#endif
#ifdef HAVE_ERRNO_H
#   include <errno.h>
#endif
#ifdef HAVE_FCNTL_H
#   include <fcntl.h>
#endif

#ifdef HAVE_UNISTD_H
#   include <unistd.h>
#elif defined( WIN32 ) && !defined( UNDER_CE )
#   include <io.h>
#endif

/* stat() support for large files on win32 */
#if defined( WIN32 ) && !defined( UNDER_CE )
#define stat _stati64
#define fstat(a,b) _fstati64(a,b)
#endif

/*****************************************************************************
 * Exported prototypes
 *****************************************************************************/
static int     Open   ( vlc_object_t * );
static void    Close  ( vlc_object_t * );

static int  Seek( access_t *, int64_t );
static int  Read( access_t *, uint8_t *, int );
static int  Control( access_t *, int, va_list );

static int OpenMediaFile( access_t *p_access, char *psz_mediafile );
static char * ReadStateFile( access_t *p_access, char *psz_statefile );
static char * GetDemuxer( access_t *p_access, char *psz_mediafile );

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
vlc_module_begin();
    set_description( "giFT state file input" );
    set_capability( "access2", 51 ); /* 51 to get invoked before file_access */
    add_shortcut( "file" );
    add_shortcut( "giftstate" );
    set_callbacks( Open, Close );
vlc_module_end();
 
/*****************************************************************************
 * _input_socket_t: private access plug-in data, modified to add private
 *                  fields
 *****************************************************************************/
struct access_sys_t
{
#ifdef WIN32
    HANDLE            fd;
#else
    int               fd;
#endif

    unsigned int      i_nb_reads;

	char             *psz_mediafile;
	int               b_manual_delete;

    vlc_bool_t        b_seekable;
    vlc_bool_t        b_pace_control;
};

/*****************************************************************************
 * Open: open the file
 *****************************************************************************/
static int Open( vlc_object_t *p_this )
{
    access_t         *p_access = (access_t*)p_this;
    access_sys_t     *p_access_data;
    char             *psz_statefile = p_access->psz_path;
	char             *psz_mediafile;
	char             *psz_demuxer;
    struct stat       stat_info;

	/* get data from state file */
	if (!(psz_mediafile = ReadStateFile (p_access, psz_statefile)))
	{
        msg_Dbg( p_access, "not a gift state file '%s'", psz_statefile );
        return VLC_EGENERIC;
	}

	/* stat the incomplete file */
    if (stat( psz_mediafile, &stat_info ) == -1)
    {
        msg_Warn( p_access, "cannot stat() media file '%s'", psz_mediafile );
		free (psz_mediafile);
        return VLC_EGENERIC;
    }

    p_access->pf_read = Read;
    p_access->pf_seek = Seek;
    p_access->pf_control = Control;
    p_access->pf_block = NULL;

    p_access->info.i_update = 0;
    p_access->info.i_size = 0;
    p_access->info.i_pos = 0;
    p_access->info.b_eof = VLC_FALSE;
    p_access->info.i_title = 0;
    p_access->info.i_seekpoint = 0;

	p_access_data = malloc( sizeof(access_sys_t) );
    p_access->p_sys = p_access_data;
    

	if( S_ISREG(stat_info.st_mode) || S_ISCHR(stat_info.st_mode) ||
	    S_ISBLK(stat_info.st_mode) )
    {
		p_access_data->b_seekable = VLC_TRUE;
		p_access_data->b_pace_control = VLC_TRUE;
	    p_access->info.i_size = stat_info.st_size;
    }
    else
    {
        msg_Err( p_access, "unknown file type for '%s'", psz_mediafile );
		free (psz_mediafile);
		free (p_access_data);
        return VLC_EGENERIC;
    }

	msg_Dbg( p_access, "incomplete file size: %d",
	         (int)p_access->info.i_size );

    msg_Dbg( p_access, "opening incomplete file '%s'", psz_mediafile );

	p_access_data->i_nb_reads = 0;
	p_access_data->psz_mediafile = psz_mediafile;
	p_access_data->b_manual_delete = 1;

	/* actually open file */
	if( OpenMediaFile( p_access, psz_mediafile ) != VLC_SUCCESS )
	{
        msg_Err( p_access, "cannot open media file '%s'", psz_mediafile );
		free (psz_mediafile);
        free (p_access_data);
        return VLC_EGENERIC;
	}

    if ( p_access_data->b_seekable &&
		 p_access->info.i_size == 0)
    {
        /* FIXME that's bad because all others access will be probed */
        msg_Err( p_access, "media file '%s' is empty, aborting",
		         psz_mediafile );

		Close (p_this);
        return VLC_EGENERIC;
    }

	/* force right demuxer if necessary */
	if ((psz_demuxer = GetDemuxer (p_access, psz_mediafile)))
	{
	    msg_Dbg( p_access, "forcing demuxer '%s'", psz_demuxer );
		p_access->psz_demux = psz_demuxer;
	}

    /* Update default_pts to a suitable value for file access */
    var_Create( p_access, "file-caching", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );

    return VLC_SUCCESS;
}

/*****************************************************************************
 * Close: close the target
 *****************************************************************************/
static void Close( vlc_object_t * p_this )
{
    access_t     *p_access = (access_t*)p_this;
    access_sys_t *p_access_data = p_access->p_sys;
    struct stat   stat_info;

    msg_Info( p_access, "closing `%s/%s://%s'", 
              p_access->psz_access, p_access->psz_demux, p_access->psz_path );
 
#ifdef WIN32
	CloseHandle( (HANDLE)p_access_data->fd );
#else
    close( p_access_data->fd );
#endif

	/* delete file if necessary */
	if (p_access_data->b_manual_delete)
	{
		/* check if state file is still there */
	    if (stat( p_access->psz_path, &stat_info ) == -1)
	    {
			msg_Info( p_access, "state file gone, removing media file '%s'",
			          p_access_data->psz_mediafile );
			
			if(unlink (p_access_data->psz_mediafile) == -1)
			{
				msg_Warn( p_access, "deletion failed '%s'",
				          p_access_data->psz_mediafile );
			}
		}
	}

	free( p_access_data->psz_mediafile );
    free( p_access_data );
}

/*****************************************************************************
 * Read: standard read on a file descriptor.
 *****************************************************************************/
static int Read( access_t * p_access, uint8_t * p_buffer, int i_len )
{
    access_sys_t *p_access_data = p_access->p_sys;
	ssize_t i_ret;

	
#ifdef WIN32
    if( !ReadFile( (HANDLE)p_access_data->fd, p_buffer, i_len,
                   (LPDWORD)&i_ret, NULL ) )
    {
        i_ret = -1;
    }
#else
    {
        /* WIN32 */
        i_ret = read( p_access_data->fd, p_buffer, i_len );