git.sesse.net Git - vlc/blob - plugins/gnome/vout_gnome.c

   1 /*****************************************************************************
   2  * vout_gnome.c: Gnome video output display method
   3  *****************************************************************************
   4  * Copyright (C) 1998, 1999, 2000 VideoLAN
   5  *
   6  * Authors:
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  21  *****************************************************************************/
  22
  23 /*****************************************************************************
  24  * Preamble
  25  *****************************************************************************/
  26 #include "defs.h"
  27
  28 #include <errno.h>                                                 /* ENOMEM */
  29 #include <stdlib.h>                                                /* free() */
  30 #include <string.h>                                            /* strerror() */
  31
  32 #ifdef SYS_BSD
  33 #include <sys/types.h>                                     /* typedef ushort */
  34 #endif
  35
  36 #include <sys/shm.h>                                   /* shmget(), shmctl() */
  37 #include <X11/Xlib.h>
  38 #include <X11/Xutil.h>
  39 #include <X11/extensions/XShm.h>
  40
  41 #include "config.h"
  42 #include "common.h"
  43 #include "threads.h"
  44 #include "mtime.h"
  45 #include "plugins.h"
  46
  47 #include "video.h"
  48 #include "video_output.h"
  49
  50 #include "intf_msg.h"
  51
  52 /*****************************************************************************
  53  * vout_sys_t: video output X11 method descriptor
  54  *****************************************************************************
  55  * This structure is part of the video output thread descriptor.
  56  * It describes the X11 specific properties of an output thread. X11 video
  57  * output is performed through regular resizable windows. Windows can be
  58  * dynamically resized to adapt to the size of the streams.
  59  *****************************************************************************/
  60 typedef struct vout_sys_s
  61 {
  62     /* User settings */
  63     boolean_t           b_shm;               /* shared memory extension flag */
  64
  65     /* Internal settings and properties */
  66     Display *           p_display;                        /* display pointer */
  67     Visual *            p_visual;                          /* visual pointer */
  68     int                 i_screen;                           /* screen number */
  69     Window              root_window;                          /* root window */
  70     Window              window;                   /* window instance handler */
  71     GC                  gc;              /* graphic context instance handler */
  72     Colormap            colormap;               /* colormap used (8bpp only) */
  73
  74     /* Display buffers and shared memory information */
  75     XImage *            p_ximage[2];                       /* XImage pointer */
  76     XShmSegmentInfo     shm_info[2];       /* shared memory zone information */
  77 } vout_sys_t;
  78
  79 /*****************************************************************************
  80  * Local prototypes
  81  *****************************************************************************/
  82 static int  X11OpenDisplay      ( vout_thread_t *p_vout, char *psz_display,
  83                                   Window root_window, void *p_data );
  84 static void X11CloseDisplay     ( vout_thread_t *p_vout );
  85 static int  X11CreateWindow     ( vout_thread_t *p_vout );
  86 static void X11DestroyWindow    ( vout_thread_t *p_vout );
  87 static int  X11CreateImage      ( vout_thread_t *p_vout, XImage **pp_ximage );
  88 static void X11DestroyImage     ( XImage *p_ximage );
  89 static int  X11CreateShmImage   ( vout_thread_t *p_vout, XImage **pp_ximage,
  90                                   XShmSegmentInfo *p_shm_info );
  91 static void X11DestroyShmImage  ( vout_thread_t *p_vout, XImage *p_ximage,
  92                                   XShmSegmentInfo *p_shm_info );
  93
  94 /*****************************************************************************
  95  * vout_GnomeCreate: allocate X11 video thread output method
  96  *****************************************************************************
  97  * This function allocate and initialize a X11 vout method. It uses some of the
  98  * vout properties to choose the window size, and change them according to the
  99  * actual properties of the display.
 100  *****************************************************************************/
 101 int vout_GnomeCreate( vout_thread_t *p_vout, char *psz_display,
 102                     int i_root_window, void *p_data )
 103 {
 104     /* Allocate structure */
 105     p_vout->p_sys = malloc( sizeof( vout_sys_t ) );
 106     if( p_vout->p_sys == NULL )
 107     {
 108         intf_ErrMsg("error: %s\n", strerror(ENOMEM) );
 109         return( 1 );
 110     }
 111
 112     /* Open and initialize device. This function issues its own error messages.
 113      * Since XLib is usually not thread-safe, we can't use the same display
 114      * pointer than the interface or another thread. However, the root window
 115      * id is still valid. */
 116     if( X11OpenDisplay( p_vout, psz_display, i_root_window, p_data ) )
 117     {
 118         intf_ErrMsg("error: can't initialize X11 display\n" );
 119         free( p_vout->p_sys );
 120         return( 1 );
 121     }
 122
 123     return( 0 );
 124 }
 125
 126 /*****************************************************************************
 127  * vout_GnomeInit: initialize X11 video thread output method
 128  *****************************************************************************
 129  * This function create the XImages needed by the output thread. It is called
 130  * at the beginning of the thread, but also each time the window is resized.
 131  *****************************************************************************/
 132 int vout_GnomeInit( vout_thread_t *p_vout )
 133 {
 134     int i_err;
 135
 136     /* Create XImages using XShm extension - on failure, fall back to regular
 137      * way (and destroy the first image if it was created successfully) */
 138     if( p_vout->p_sys->b_shm )
 139     {
 140         /* Create first image */
 141         i_err = X11CreateShmImage( p_vout, &p_vout->p_sys->p_ximage[0],
 142                                    &p_vout->p_sys->shm_info[0] );
 143         if( !i_err )                         /* first image has been created */
 144         {
 145             /* Create second image */
 146             if( X11CreateShmImage( p_vout, &p_vout->p_sys->p_ximage[1],
 147                                    &p_vout->p_sys->shm_info[1] ) )
 148             {                             /* error creating the second image */
 149                 X11DestroyShmImage( p_vout, p_vout->p_sys->p_ximage[0],
 150                                     &p_vout->p_sys->shm_info[0] );
 151                 i_err = 1;
 152             }
 153         }
 154         if( i_err )                                      /* an error occured */
 155         {
 156             intf_Msg("XShm video extension deactivated\n" );
 157             p_vout->p_sys->b_shm = 0;
 158         }
 159     }
 160
 161     /* Create XImages without XShm extension */
 162     if( !p_vout->p_sys->b_shm )
 163     {
 164         if( X11CreateImage( p_vout, &p_vout->p_sys->p_ximage[0] ) )
 165         {
 166             intf_ErrMsg("error: can't create images\n");
 167             p_vout->p_sys->p_ximage[0] = NULL;
 168             p_vout->p_sys->p_ximage[1] = NULL;
 169             return( 1 );
 170         }
 171         if( X11CreateImage( p_vout, &p_vout->p_sys->p_ximage[1] ) )
 172         {
 173             intf_ErrMsg("error: can't create images\n");
 174             X11DestroyImage( p_vout->p_sys->p_ximage[0] );
 175             p_vout->p_sys->p_ximage[0] = NULL;
 176             p_vout->p_sys->p_ximage[1] = NULL;
 177             return( 1 );
 178         }
 179     }
 180
 181     /* Set bytes per line and initialize buffers */
 182     p_vout->i_bytes_per_line = p_vout->p_sys->p_ximage[0]->bytes_per_line;
 183     vout_SetBuffers( p_vout, p_vout->p_sys->p_ximage[ 0 ]->data,
 184                      p_vout->p_sys->p_ximage[ 1 ]->data );
 185     return( 0 );
 186 }
 187
 188 /*****************************************************************************
 189  * vout_GnomeEnd: terminate X11 video thread output method
 190  *****************************************************************************
 191  * Destroy the X11 XImages created by vout_SysInit. It is called at the end of
 192  * the thread, but also each time the window is resized.
 193  *****************************************************************************/
 194 void vout_GnomeEnd( vout_thread_t *p_vout )
 195 {
 196     if( p_vout->p_sys->b_shm )                             /* Shm XImages... */
 197     {
 198         X11DestroyShmImage( p_vout, p_vout->p_sys->p_ximage[0],
 199                             &p_vout->p_sys->shm_info[0] );
 200         X11DestroyShmImage( p_vout, p_vout->p_sys->p_ximage[1],
 201                             &p_vout->p_sys->shm_info[1] );
 202     }
 203     else                                          /* ...or regular XImages */
 204     {
 205         X11DestroyImage( p_vout->p_sys->p_ximage[0] );
 206         X11DestroyImage( p_vout->p_sys->p_ximage[1] );
 207     }
 208 }
 209
 210 /*****************************************************************************
 211  * vout_GnomeDestroy: destroy X11 video thread output method
 212  *****************************************************************************
 213  * Terminate an output method created by vout_CreateOutputMethod
 214  *****************************************************************************/
 215 void vout_GnomeDestroy( vout_thread_t *p_vout )
 216 {
 217     X11CloseDisplay( p_vout );
 218     free( p_vout->p_sys );
 219 }
 220
 221 /*****************************************************************************
 222  * vout_GnomeManage: handle X11 events
 223  *****************************************************************************
 224  * This function should be called regularly by video output thread. It manages
 225  * X11 events and allows window resizing. It returns a non null value on
 226  * error.
 227  *****************************************************************************/
 228 int vout_GnomeManage( vout_thread_t *p_vout )
 229 {
 230     /*
 231      * Color/Grayscale or gamma change: in 8bpp, just change the colormap
 232      */
 233     if( (p_vout->i_changes & VOUT_GRAYSCALE_CHANGE) && (p_vout->i_screen_depth == 8) )
 234     {
 235         /* FIXME: clear flags ?? */
 236     }
 237
 238     /*
 239      * Size change
 240      */
 241     if( p_vout->i_changes & VOUT_SIZE_CHANGE )
 242     {
 243         intf_DbgMsg("resizing window\n");
 244         p_vout->i_changes &= ~VOUT_SIZE_CHANGE;
 245
 246         /* Resize window */
 247         XResizeWindow( p_vout->p_sys->p_display, p_vout->p_sys->window,
 248                        p_vout->i_width, p_vout->i_height );
 249
 250         /* Destroy XImages to change their size */
 251         vout_GnomeEnd( p_vout );
 252
 253         /* Recreate XImages. If SysInit failed, the thread can't go on. */
 254         if( vout_GnomeInit( p_vout ) )
 255         {
 256             intf_ErrMsg("error: can't resize display\n");
 257             return( 1 );
 258         }
 259
 260         /* Tell the video output thread that it will need to rebuild YUV
 261          * tables. This is needed since convertion buffer size may have changed */
 262         p_vout->i_changes |= VOUT_YUV_CHANGE;
 263         intf_Msg("Video display resized (%dx%d)\n", p_vout->i_width, p_vout->i_height);
 264     }
 265
 266     return 0;
 267 }
 268
 269 /*****************************************************************************
 270  * vout_GnomeDisplay: displays previously rendered output
 271  *****************************************************************************
 272  * This function send the currently rendered image to X11 server, wait until
 273  * it is displayed and switch the two rendering buffer, preparing next frame.
 274  *****************************************************************************/
 275 void vout_GnomeDisplay( vout_thread_t *p_vout )
 276 {
 277     if( p_vout->p_sys->b_shm)                                /* XShm is used */
 278     {
 279         /* Display rendered image using shared memory extension */
 280         XShmPutImage(p_vout->p_sys->p_display, p_vout->p_sys->window, p_vout->p_sys->gc,
 281                      p_vout->p_sys->p_ximage[ p_vout->i_buffer_index ],
 282                      0, 0, 0, 0,
 283                      p_vout->p_sys->p_ximage[ p_vout->i_buffer_index ]->width,
 284                      p_vout->p_sys->p_ximage[ p_vout->i_buffer_index ]->height, True);
 285
 286         /* Send the order to the X server */
 287         XFlush(p_vout->p_sys->p_display);
 288     }
 289     else                                /* regular X11 capabilities are used */
 290     {
 291         XPutImage(p_vout->p_sys->p_display, p_vout->p_sys->window, p_vout->p_sys->gc,
 292                   p_vout->p_sys->p_ximage[ p_vout->i_buffer_index ],
 293                   0, 0, 0, 0,
 294                   p_vout->p_sys->p_ximage[ p_vout->i_buffer_index ]->width,
 295                   p_vout->p_sys->p_ximage[ p_vout->i_buffer_index ]->height);
 296
 297         /* Send the order to the X server */
 298         XFlush(p_vout->p_sys->p_display);
 299     }
 300 }
 301
 302 /*****************************************************************************
 303  * vout_GnomeSetPalette: sets an 8 bpp palette
 304  *****************************************************************************
 305  * This function sets the palette given as an argument. It does not return
 306  * anything, but could later send information on which colors it was unable
 307  * to set.
 308  *****************************************************************************/
 309 void vout_GnomeSetPalette( p_vout_thread_t p_vout,
 310                            u16 *red, u16 *green, u16 *blue, u16 *transp )
 311 {
 312     int i;
 313     XColor color[255];
 314
 315     intf_DbgMsg( "Palette change called\n" );
 316
 317     /* allocate palette */
 318     for( i = 0; i < 255; i++ )
 319     {
 320         /* kludge: colors are indexed reversely because color 255 seems
 321          * to be reserved for black even if we try to set it to white */
 322         color[i].pixel = 255-i;
 323         color[i].pad = 0;
 324         color[i].flags = DoRed|DoGreen|DoBlue;
 325         color[i].red = red[255-i];
 326         color[i].blue = blue[255-i];
 327         color[i].green = green[255-i];
 328     }
 329
 330     XStoreColors( p_vout->p_sys->p_display, p_vout->p_sys->colormap, color, 256 );
 331 }
 332
 333 /* following functions are local */
 334
 335 /*****************************************************************************
 336  * X11OpenDisplay: open and initialize X11 device
 337  *****************************************************************************
 338  * Create a window according to video output given size, and set other
 339  * properties according to the display properties.
 340  *****************************************************************************/
 341 static int X11OpenDisplay( vout_thread_t *p_vout, char *psz_display, Window root_window, void *p_data )
 342 {
 343     XPixmapFormatValues *       p_xpixmap_format;          /* pixmap formats */
 344     XVisualInfo *               p_xvisual;           /* visuals informations */
 345     XVisualInfo                 xvisual_template;         /* visual template */
 346     int                         i_count;                       /* array size */
 347
 348     /* Open display */
 349     p_vout->p_sys->p_display = XOpenDisplay( psz_display );
 350     if( p_vout->p_sys->p_display == NULL )
 351     {
 352         intf_ErrMsg("error: can't open display %s\n", psz_display );
 353         return( 1 );
 354     }
 355
 356     /* Initialize structure */
 357     p_vout->p_sys->root_window  = root_window;
 358     p_vout->p_sys->b_shm        = (XShmQueryExtension(p_vout->p_sys->p_display) == True);
 359     p_vout->p_sys->i_screen     = DefaultScreen( p_vout->p_sys->p_display );
 360     if( !p_vout->p_sys->b_shm )
 361     {
 362         intf_Msg("XShm video extension is not available\n");
 363     }
 364
 365     /* Get screen depth */
 366     p_vout->i_screen_depth = XDefaultDepth( p_vout->p_sys->p_display, p_vout->p_sys->i_screen );
 367     switch( p_vout->i_screen_depth )
 368     {
 369     case 8:
 370         /*
 371          * Screen depth is 8bpp. Use PseudoColor visual with private colormap.
 372          */
 373         xvisual_template.screen =   p_vout->p_sys->i_screen;
 374         xvisual_template.class =    DirectColor;
 375         p_xvisual = XGetVisualInfo( p_vout->p_sys->p_display, VisualScreenMask | VisualClassMask,
 376                                     &xvisual_template, &i_count );
 377         if( p_xvisual == NULL )
 378         {
 379             intf_ErrMsg("error: no PseudoColor visual available\n");
 380             XCloseDisplay( p_vout->p_sys->p_display );
 381             return( 1 );
 382         }
 383         p_vout->i_bytes_per_pixel = 1;
 384
 385         /* put the colormap in place */
 386         p_vout->p_sys->colormap = *(Colormap *)p_data;
 387         break;
 388     case 15:
 389     case 16:
 390     case 24:
 391     default:
 392         /*
 393          * Screen depth is higher than 8bpp. TrueColor visual is used.
 394          */
 395         xvisual_template.screen =   p_vout->p_sys->i_screen;
 396         xvisual_template.class =    TrueColor;
 397         p_xvisual = XGetVisualInfo( p_vout->p_sys->p_display, VisualScreenMask | VisualClassMask,
 398                                     &xvisual_template, &i_count );
 399         if( p_xvisual == NULL )
 400         {
 401             intf_ErrMsg("error: no TrueColor visual available\n");
 402             XCloseDisplay( p_vout->p_sys->p_display );
 403             return( 1 );
 404         }
 405         p_vout->i_red_mask =        p_xvisual->red_mask;
 406         p_vout->i_green_mask =      p_xvisual->green_mask;
 407         p_vout->i_blue_mask =       p_xvisual->blue_mask;
 408
 409         /* There is no difference yet between 3 and 4 Bpp. The only way to find
 410          * the actual number of bytes per pixel is to list supported pixmap
 411          * formats. */
 412         p_xpixmap_format = XListPixmapFormats( p_vout->p_sys->p_display, &i_count );
 413         p_vout->i_bytes_per_pixel = 0;
 414         for( ; i_count--; p_xpixmap_format++ )
 415         {
 416             if( p_xpixmap_format->bits_per_pixel / 8 > p_vout->i_bytes_per_pixel )
 417             {
 418                 p_vout->i_bytes_per_pixel = p_xpixmap_format->bits_per_pixel / 8;
 419             }
 420         }
 421         break;
 422     }
 423     p_vout->p_sys->p_visual = p_xvisual->visual;
 424     XFree( p_xvisual );
 425
 426     /* Create a window */
 427     if( X11CreateWindow( p_vout ) )
 428     {
 429         intf_ErrMsg("error: can't open a window\n");
 430         XCloseDisplay( p_vout->p_sys->p_display );
 431         return( 1 );
 432     }
 433     return( 0 );
 434 }
 435
 436 /*****************************************************************************
 437  * X11CloseDisplay: close X11 device
 438  *****************************************************************************
 439  * Returns all resources allocated by X11OpenDisplay and restore the original
 440  * state of the display.
 441  *****************************************************************************/
 442 static void X11CloseDisplay( vout_thread_t *p_vout )
 443 {
 444     /* Destroy colormap */
 445     if( p_vout->i_screen_depth == 8 )
 446     {
 447         XFreeColormap( p_vout->p_sys->p_display, p_vout->p_sys->colormap );
 448     }
 449
 450     /* Destroy window */
 451     X11DestroyWindow( p_vout );
 452
 453     /* FIXME: We should close the display here, but X returns an error. */
 454     //XCloseDisplay( p_vout->p_sys->p_display );
 455 }
 456
 457 /*****************************************************************************
 458  * X11CreateWindow: create X11 vout window
 459  *****************************************************************************
 460  * The video output window will be created. Normally, this window is wether
 461  * full screen or part of a parent window. Therefore, it does not need a
 462  * title or other hints. Thery are still supplied in case the window would be
 463  * spawned as a standalone one by the interface.
 464  *****************************************************************************/
 465 static int X11CreateWindow( vout_thread_t *p_vout )
 466 {
 467     XSetWindowAttributes    xwindow_attributes;         /* window attributes */
 468     XGCValues               xgcvalues;      /* graphic context configuration */
 469     XEvent                  xevent;                          /* first events */
 470     boolean_t               b_expose;             /* 'expose' event received */
 471     boolean_t               b_map_notify;     /* 'map_notify' event received */
 472
 473     /* Prepare window attributes */
 474     xwindow_attributes.backing_store = Always;       /* save the hidden part */
 475
 476     /* Create the window and set hints */
 477     p_vout->p_sys->window = XCreateSimpleWindow( p_vout->p_sys->p_display,
 478                                          p_vout->p_sys->root_window,
 479                                          0, 0,
 480                                          p_vout->i_width, p_vout->i_height,
 481                                          0, 0, 0);
 482     XSelectInput( p_vout->p_sys->p_display, p_vout->p_sys->window,
 483                   ExposureMask | StructureNotifyMask );
 484     XChangeWindowAttributes( p_vout->p_sys->p_display, p_vout->p_sys->window,
 485                              CWBackingStore, &xwindow_attributes);
 486
 487     /* Creation of a graphic context that doesn't generate a GraphicsExpose event
 488        when using functions like XCopyArea */
 489     xgcvalues.graphics_exposures = False;
 490     p_vout->p_sys->gc =  XCreateGC( p_vout->p_sys->p_display, p_vout->p_sys->window,
 491                                     GCGraphicsExposures, &xgcvalues);
 492
 493     /* Send orders to server, and wait until window is displayed - two events
 494      * must be received: a MapNotify event, an Expose event allowing drawing in the
 495      * window */
 496     b_expose = 0;
 497     b_map_notify = 0;
 498     XMapWindow( p_vout->p_sys->p_display, p_vout->p_sys->window);
 499     do
 500     {
 501         XNextEvent( p_vout->p_sys->p_display, &xevent);
 502         if( (xevent.type == Expose)
 503             && (xevent.xexpose.window == p_vout->p_sys->window) )
 504         {
 505             b_expose = 1;
 506         }
 507         else if( (xevent.type == MapNotify)
 508                  && (xevent.xmap.window == p_vout->p_sys->window) )
 509         {
 510             b_map_notify = 1;
 511         }
 512     }
 513     while( !( b_expose && b_map_notify ) );
 514     XSelectInput( p_vout->p_sys->p_display, p_vout->p_sys->window, 0 );
 515
 516     /* At this stage, the window is open, displayed, and ready to receive
 517      * data */
 518     return( 0 );
 519 }
 520
 521 /*****************************************************************************
 522  * X11DestroyWindow: destroy X11 window
 523  *****************************************************************************
 524  * Destroy an X11 window created by vout_CreateWindow
 525  *****************************************************************************/
 526 static void X11DestroyWindow( vout_thread_t *p_vout )
 527 {
 528     XUnmapWindow( p_vout->p_sys->p_display, p_vout->p_sys->window );
 529     XFreeGC( p_vout->p_sys->p_display, p_vout->p_sys->gc );
 530     XDestroyWindow( p_vout->p_sys->p_display, p_vout->p_sys->window );
 531 }
 532
 533 /*****************************************************************************
 534  * X11CreateImage: create an XImage
 535  *****************************************************************************
 536  * Create a simple XImage used as a buffer.
 537  *****************************************************************************/
 538 static int X11CreateImage( vout_thread_t *p_vout, XImage **pp_ximage )
 539 {
 540     byte_t *    pb_data;                          /* image data storage zone */
 541     int         i_quantum;                     /* XImage quantum (see below) */
 542
 543     /* Allocate memory for image */
 544     p_vout->i_bytes_per_line = p_vout->i_width * p_vout->i_bytes_per_pixel;
 545     pb_data = (byte_t *) malloc( p_vout->i_bytes_per_line * p_vout->i_height );
 546     if( !pb_data )                                                  /* error */
 547     {
 548         intf_ErrMsg("error: %s\n", strerror(ENOMEM));
 549         return( 1 );
 550     }
 551
 552     /* Optimize the quantum of a scanline regarding its size - the quantum is
 553        a diviser of the number of bits between the start of two scanlines. */
 554     if( !(( p_vout->i_bytes_per_line ) % 32) )
 555     {
 556         i_quantum = 32;
 557     }
 558     else
 559     {
 560         if( !(( p_vout->i_bytes_per_line ) % 16) )
 561         {
 562             i_quantum = 16;
 563         }
 564         else
 565         {
 566             i_quantum = 8;
 567         }
 568     }
 569
 570     /* Create XImage */
 571     *pp_ximage = XCreateImage( p_vout->p_sys->p_display, p_vout->p_sys->p_visual,
 572                                p_vout->i_screen_depth, ZPixmap, 0, pb_data,
 573                                p_vout->i_width, p_vout->i_height, i_quantum, 0);
 574     if(! *pp_ximage )                                               /* error */
 575     {
 576         intf_ErrMsg( "error: XCreateImage() failed\n" );
 577         free( pb_data );
 578         return( 1 );
 579     }
 580
 581     return 0;
 582 }
 583
 584 /*****************************************************************************
 585  * X11CreateShmImage: create an XImage using shared memory extension
 586  *****************************************************************************
 587  * Prepare an XImage for DisplayX11ShmImage function.
 588  * The order of the operations respects the recommandations of the mit-shm
 589  * document by J.Corbet and K.Packard. Most of the parameters were copied from
 590  * there.
 591  *****************************************************************************/
 592 static int X11CreateShmImage( vout_thread_t *p_vout, XImage **pp_ximage,
 593                               XShmSegmentInfo *p_shm_info)
 594 {
 595     /* Create XImage */
 596     *pp_ximage = XShmCreateImage( p_vout->p_sys->p_display, p_vout->p_sys->p_visual,
 597                                   p_vout->i_screen_depth, ZPixmap, 0,
 598                                   p_shm_info, p_vout->i_width, p_vout->i_height );
 599     if(! *pp_ximage )                                               /* error */
 600     {
 601         intf_ErrMsg("error: XShmCreateImage() failed\n");
 602         return( 1 );
 603     }
 604
 605     /* Allocate shared memory segment - 0777 set the access permission
 606      * rights (like umask), they are not yet supported by X servers */
 607     p_shm_info->shmid = shmget( IPC_PRIVATE,
 608                                 (*pp_ximage)->bytes_per_line * (*pp_ximage)->height,
 609                                 IPC_CREAT | 0777);
 610     if( p_shm_info->shmid < 0)                                      /* error */
 611     {
 612         intf_ErrMsg("error: can't allocate shared image data (%s)\n",
 613                     strerror(errno));
 614         XDestroyImage( *pp_ximage );
 615         return( 1 );
 616     }
 617
 618     /* Attach shared memory segment to process (read/write) */
 619     p_shm_info->shmaddr = (*pp_ximage)->data = shmat(p_shm_info->shmid, 0, 0);
 620     if(! p_shm_info->shmaddr )
 621     {                                                               /* error */
 622         intf_ErrMsg("error: can't attach shared memory (%s)\n",
 623                     strerror(errno));
 624         shmctl( p_shm_info->shmid, IPC_RMID, 0 );      /* free shared memory */
 625         XDestroyImage( *pp_ximage );
 626         return( 1 );
 627     }
 628
 629     /* Mark the shm segment to be removed when there will be no more
 630      * attachements, so it is automatic on process exit or after shmdt */
 631     shmctl( p_shm_info->shmid, IPC_RMID, 0 );
 632
 633     /* Attach shared memory segment to X server (read only) */
 634     p_shm_info->readOnly = True;
 635     if( XShmAttach( p_vout->p_sys->p_display, p_shm_info ) == False )    /* error */
 636     {
 637         intf_ErrMsg("error: can't attach shared memory to X11 server\n");
 638         shmdt( p_shm_info->shmaddr );     /* detach shared memory from process
 639                                            * and automatic free                */
 640         XDestroyImage( *pp_ximage );
 641         return( 1 );
 642     }
 643
 644     /* Send image to X server. This instruction is required, since having
 645      * built a Shm XImage and not using it causes an error on XCloseDisplay */
 646     XFlush( p_vout->p_sys->p_display );
 647     return( 0 );
 648 }
 649
 650 /*****************************************************************************
 651  * X11DestroyImage: destroy an XImage
 652  *****************************************************************************
 653  * Destroy XImage AND associated data. If pointer is NULL, the image won't be
 654  * destroyed (see vout_ManageOutputMethod())
 655  *****************************************************************************/
 656 static void X11DestroyImage( XImage *p_ximage )
 657 {
 658     if( p_ximage != NULL )
 659     {
 660         XDestroyImage( p_ximage );                     /* no free() required */
 661     }
 662 }
 663
 664 /*****************************************************************************
 665  * X11DestroyShmImage
 666  *****************************************************************************
 667  * Destroy XImage AND associated data. Detach shared memory segment from
 668  * server and process, then free it. If pointer is NULL, the image won't be
 669  * destroyed (see vout_ManageOutputMethod())
 670  *****************************************************************************/
 671 static void X11DestroyShmImage( vout_thread_t *p_vout, XImage *p_ximage,
 672                                 XShmSegmentInfo *p_shm_info )
 673 {
 674     /* If pointer is NULL, do nothing */
 675     if( p_ximage == NULL )
 676     {
 677         return;
 678     }
 679
 680     XShmDetach( p_vout->p_sys->p_display, p_shm_info );     /* detach from server */
 681     XDestroyImage( p_ximage );
 682     if( shmdt( p_shm_info->shmaddr ) )  /* detach shared memory from process */
 683     {                                   /* also automatic freeing...         */
 684         intf_ErrMsg( "error: can't detach shared memory (%s)\n",
 685                      strerror(errno) );
 686     }
 687 }
 688
 689