fb.c

video linux conference

/*****************************************************************************
 * fb.c : framebuffer plugin for vlc
 *****************************************************************************
 * Copyright (C) 2000, 2001 VideoLAN
 * $Id: fb.c 11387 2005-06-10 15:32:08Z hartman $
 *
 * Authors: Samuel Hocevar <[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.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <errno.h>                                                 /* ENOMEM */
#include <signal.h>                                      /* SIGUSR1, SIGUSR2 */
#include <stdlib.h>                                                /* free() */
#include <string.h>                                            /* strerror() */
#include <fcntl.h>                                                 /* open() */
#include <unistd.h>                                               /* close() */

#include <termios.h>                                       /* struct termios */
#include <sys/ioctl.h>
#include <sys/mman.h>                                              /* mmap() */

#include <linux/fb.h>
#include <linux/vt.h>                                                /* VT_* */
#include <linux/kd.h>                                                 /* KD* */

#include <vlc/vlc.h>
#include <vlc/vout.h>

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static int  Create    ( vlc_object_t * );
static void Destroy   ( vlc_object_t * );

static int  Init      ( vout_thread_t * );
static void End       ( vout_thread_t * );
static int  Manage    ( vout_thread_t * );
static void Display   ( vout_thread_t *, picture_t * );

static int  OpenDisplay    ( vout_thread_t * );
static void CloseDisplay   ( vout_thread_t * );
static void SwitchDisplay  ( int i_signal );
static void TextMode       ( int i_tty );
static void GfxMode        ( int i_tty );

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
#define FB_DEV_VAR "fbdev"

#define DEVICE_TEXT N_("Framebuffer device")
#define DEVICE_LONGTEXT N_( \
    "You can select here the framebuffer device that will be used " \
    "for rendering (usually /dev/fb0).")

vlc_module_begin();
    set_shortname( "Framebuffer" );
    set_category( CAT_VIDEO );
    set_subcategory( SUBCAT_VIDEO_VOUT );
    add_file( FB_DEV_VAR, "/dev/fb0", NULL, DEVICE_TEXT, DEVICE_LONGTEXT,
              VLC_FALSE );
    set_description( _("GNU/Linux console framebuffer video output") );
    set_capability( "video output", 30 );
    set_callbacks( Create, Destroy );
vlc_module_end();

/*****************************************************************************
 * vout_sys_t: video output framebuffer method descriptor
 *****************************************************************************
 * This structure is part of the video output thread descriptor.
 * It describes the FB specific properties of an output thread.
 *****************************************************************************/
struct vout_sys_t
{
    /* System information */
    int                 i_tty;                          /* tty device handle */
    struct termios      old_termios;

    /* Original configuration information */
    struct sigaction            sig_usr1;           /* USR1 previous handler */
    struct sigaction            sig_usr2;           /* USR2 previous handler */
    struct vt_mode              vt_mode;                 /* previous VT mode */

    /* Framebuffer information */
    int                         i_fd;                       /* device handle */
    struct fb_var_screeninfo    old_info;       /* original mode information */
    struct fb_var_screeninfo    var_info;        /* current mode information */
    vlc_bool_t                  b_pan;     /* does device supports panning ? */
    struct fb_cmap              fb_cmap;                /* original colormap */
    uint16_t                    *p_palette;              /* original palette */

    /* Video information */
    int i_width;
    int i_height;
    int i_bytes_per_pixel;

    /* Video memory */
    byte_t *    p_video;                                      /* base adress */
    size_t      i_page_size;                                    /* page size */
};

/*****************************************************************************
 * Create: allocates FB video thread output method
 *****************************************************************************
 * This function allocates and initializes a FB vout method.
 *****************************************************************************/
static int Create( vlc_object_t *p_this )
{
    vout_thread_t *p_vout = (vout_thread_t *)p_this;

    struct sigaction    sig_tty;                 /* sigaction for tty change */
    struct vt_mode      vt_mode;                          /* vt current mode */
    struct termios      new_termios;

    /* Allocate instance and initialize some members */
    p_vout->p_sys = malloc( sizeof( vout_sys_t ) );
    if( p_vout->p_sys == NULL )
    {
        return VLC_ENOMEM;
    };

    p_vout->pf_init = Init;
    p_vout->pf_end = End;
    p_vout->pf_manage = Manage;
    p_vout->pf_render = NULL;
    p_vout->pf_display = Display;

    /* Set tty and fb devices */
    p_vout->p_sys->i_tty = 0;           /* 0 == /dev/tty0 == current console */

    GfxMode( p_vout->p_sys->i_tty );

    /* Set keyboard settings */
    if (tcgetattr(0, &p_vout->p_sys->old_termios) == -1)
    {
        msg_Err( p_vout, "tcgetattr failed" );
    }

    if (tcgetattr(0, &new_termios) == -1)
    {
        msg_Err( p_vout, "tcgetattr failed" );
    }

 /* new_termios.c_lflag &= ~ (ICANON | ISIG);
    new_termios.c_lflag |= (ECHO | ECHOCTL); */
    new_termios.c_lflag &= ~ (ICANON);
    new_termios.c_lflag &= ~(ECHO | ECHOCTL);
    new_termios.c_iflag = 0;
    new_termios.c_cc[VMIN] = 1;
    new_termios.c_cc[VTIME] = 0;

    if (tcsetattr(0, TCSAFLUSH, &new_termios) == -1)
    {
        msg_Err( p_vout, "tcsetattr failed" );
    }

    ioctl( p_vout->p_sys->i_tty, VT_RELDISP, VT_ACKACQ );

    /* Set-up tty signal handler to be aware of tty changes */
    memset( &sig_tty, 0, sizeof( sig_tty ) );
    sig_tty.sa_handler = SwitchDisplay;
    sigemptyset( &sig_tty.sa_mask );
    if( sigaction( SIGUSR1, &sig_tty, &p_vout->p_sys->sig_usr1 ) ||
        sigaction( SIGUSR2, &sig_tty, &p_vout->p_sys->sig_usr2 ) )
    {
        msg_Err( p_vout, "cannot set signal handler (%s)", strerror(errno) );
        tcsetattr(0, 0, &p_vout->p_sys->old_termios);
        TextMode( p_vout->p_sys->i_tty );
        free( p_vout->p_sys );
        return VLC_EGENERIC;
    }

    /* Set-up tty according to new signal handler */
    if( -1 == ioctl( p_vout->p_sys->i_tty,
                     VT_GETMODE, &p_vout->p_sys->vt_mode ) )
    {
        msg_Err( p_vout, "cannot get terminal mode (%s)", strerror(errno) );
        sigaction( SIGUSR1, &p_vout->p_sys->sig_usr1, NULL );
        sigaction( SIGUSR2, &p_vout->p_sys->sig_usr2, NULL );
        tcsetattr(0, 0, &p_vout->p_sys->old_termios);
        TextMode( p_vout->p_sys->i_tty );
        free( p_vout->p_sys );
        return VLC_EGENERIC;
    }
    memcpy( &vt_mode, &p_vout->p_sys->vt_mode, sizeof( vt_mode ) );
    vt_mode.mode   = VT_PROCESS;
    vt_mode.waitv  = 0;
    vt_mode.relsig = SIGUSR1;
    vt_mode.acqsig = SIGUSR2;

    if( -1 == ioctl( p_vout->p_sys->i_tty, VT_SETMODE, &vt_mode ) )
    {
        msg_Err( p_vout, "cannot set terminal mode (%s)", strerror(errno) );
        sigaction( SIGUSR1, &p_vout->p_sys->sig_usr1, NULL );
        sigaction( SIGUSR2, &p_vout->p_sys->sig_usr2, NULL );
        tcsetattr(0, 0, &p_vout->p_sys->old_termios);
        TextMode( p_vout->p_sys->i_tty );
        free( p_vout->p_sys );
        return VLC_EGENERIC;
    }

    if( OpenDisplay( p_vout ) )
    {
        ioctl( p_vout->p_sys->i_tty, VT_SETMODE, &p_vout->p_sys->vt_mode );
        sigaction( SIGUSR1, &p_vout->p_sys->sig_usr1, NULL );
        sigaction( SIGUSR2, &p_vout->p_sys->sig_usr2, NULL );
        tcsetattr(0, 0, &p_vout->p_sys->old_termios);
        TextMode( p_vout->p_sys->i_tty );
        free( p_vout->p_sys );
        return VLC_EGENERIC;
    }

    return VLC_SUCCESS;
}

/*****************************************************************************
 * Init: initialize framebuffer video thread output method
 *****************************************************************************/
static int Init( vout_thread_t *p_vout )
{
    int i_index;
    picture_t *p_pic;

    I_OUTPUTPICTURES = 0;

    /* Initialize the output structure: RGB with square pixels, whatever
     * the input format is, since it's the only format we know */
    switch( p_vout->p_sys->var_info.bits_per_pixel )
    {
        case 8: /* FIXME: set the palette */
            p_vout->output.i_chroma = VLC_FOURCC('R','G','B','2'); break;
        case 15:
            p_vout->output.i_chroma = VLC_FOURCC('R','V','1','5'); break;
        case 16:
            p_vout->output.i_chroma = VLC_FOURCC('R','V','1','6'); break;
        case 24:
            p_vout->output.i_chroma = VLC_FOURCC('R','V','2','4'); break;
        case 32:
            p_vout->output.i_chroma = VLC_FOURCC('R','V','3','2'); break;
        default:
            msg_Err( p_vout, "unknown screen depth %i",
                     p_vout->p_sys->var_info.bits_per_pixel );
            return VLC_EGENERIC;
    }

    /* Only useful for p_vout->p_sys->var_info.bits_per_pixel != 8 */
    p_vout->output.i_rmask = ( (1 << p_vout->p_sys->var_info.red.length) - 1 )
                     << p_vout->p_sys->var_info.red.offset;
    p_vout->output.i_gmask = ( (1 << p_vout->p_sys->var_info.green.length) - 1 )
                     << p_vout->p_sys->var_info.green.offset;
    p_vout->output.i_bmask = ( (1 << p_vout->p_sys->var_info.blue.length) - 1 )
                     << p_vout->p_sys->var_info.blue.offset;

    p_vout->output.i_width = p_vout->p_sys->i_width;
    p_vout->output.i_height = p_vout->p_sys->i_height;

    /* Assume we have square pixels */
    p_vout->output.i_aspect = p_vout->p_sys->i_width
                               * VOUT_ASPECT_FACTOR / p_vout->p_sys->i_height;

    /* Clear the screen */
    memset( p_vout->p_sys->p_video, 0, p_vout->p_sys->i_page_size );

    /* Try to initialize 1 direct buffer */
    p_pic = NULL;

    /* Find an empty picture slot */
    for( i_index = 0 ; i_index < VOUT_MAX_PICTURES ; i_index++ )
    {
        if( p_vout->p_picture[ i_index ].i_status == FREE_PICTURE )
        {
            p_pic = p_vout->p_picture + i_index;
            break;
        }
    }

    /* Allocate the picture */
    if( p_pic == NULL )
    {
        return VLC_EGENERIC;
    }

    /* We know the chroma, allocate a buffer which will be used
     * directly by the decoder */
    p_pic->p->p_pixels = p_vout->p_sys->p_video;
    p_pic->p->i_pixel_pitch = p_vout->p_sys->i_bytes_per_pixel;
    p_pic->p->i_lines = p_vout->p_sys->var_info.yres;
    p_pic->p->i_visible_lines = p_vout->p_sys->var_info.yres;

    if( p_vout->p_sys->var_info.xres_virtual )
    {
        p_pic->p->i_pitch = p_vout->p_sys->var_info.xres_virtual
                             * p_vout->p_sys->i_bytes_per_pixel;
    }
    else
    {
        p_pic->p->i_pitch = p_vout->p_sys->var_info.xres
                             * p_vout->p_sys->i_bytes_per_pixel;
    }

    p_pic->p->i_visible_pitch = p_vout->p_sys->var_info.xres
                                 * p_vout->p_sys->i_bytes_per_pixel;

    p_pic->i_planes = 1;

    p_pic->i_status = DESTROYED_PICTURE;
    p_pic->i_type   = DIRECT_PICTURE;

    PP_OUTPUTPICTURE[ I_OUTPUTPICTURES ] = p_pic;

    I_OUTPUTPICTURES++;

    return VLC_SUCCESS;
}

/*****************************************************************************
 * End: terminate framebuffer video thread output method
 *****************************************************************************/
static void End( vout_thread_t *p_vout )
{
    /* Clear the screen */
    memset( p_vout->p_sys->p_video, 0, p_vout->p_sys->i_page_size );
}

/*****************************************************************************
 * Destroy: destroy FB video thread output method
 *****************************************************************************
 * Terminate an output method created by Create
 *****************************************************************************/
static void Destroy( vlc_object_t *p_this )
{
    vout_thread_t *p_vout = (vout_thread_t *)p_this;

    CloseDisplay( p_vout );

    /* Reset the terminal */