src/glx/drisw_glx.c

   1 /*
   2  * Copyright 2008 George Sapountzis
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23
  24 #if defined(GLX_DIRECT_RENDERING) && !defined(GLX_USE_APPLEGL)
  25
  26 #include <X11/Xlib.h>
  27 #include "glxclient.h"
  28 #include <dlfcn.h>
  29 #include "dri_common.h"
  30
  31 struct drisw_display
  32 {
  33    __GLXDRIdisplay base;
  34 };
  35
  36 struct drisw_context
  37 {
  38    struct glx_context base;
  39    __DRIcontext *driContext;
  40
  41 };
  42
  43 struct drisw_screen
  44 {
  45    struct glx_screen base;
  46
  47    __DRIscreen *driScreen;
  48    __GLXDRIscreen vtable;
  49    const __DRIcoreExtension *core;
  50    const __DRIswrastExtension *swrast;
  51    const __DRItexBufferExtension *texBuffer;
  52    const __DRIcopySubBufferExtension *copySubBuffer;
  53
  54    const __DRIconfig **driver_configs;
  55
  56    void *driver;
  57 };
  58
  59 struct drisw_drawable
  60 {
  61    __GLXDRIdrawable base;
  62
  63    GC gc;
  64    GC swapgc;
  65
  66    __DRIdrawable *driDrawable;
  67    XVisualInfo *visinfo;
  68    XImage *ximage;
  69 };
  70
  71 static Bool
  72 XCreateDrawable(struct drisw_drawable * pdp,
  73                 Display * dpy, XID drawable, int visualid)
  74 {
  75    XGCValues gcvalues;
  76    long visMask;
  77    XVisualInfo visTemp;
  78    int num_visuals;
  79
  80    /* create GC's */
  81    pdp->gc = XCreateGC(dpy, drawable, 0, NULL);
  82    pdp->swapgc = XCreateGC(dpy, drawable, 0, NULL);
  83
  84    gcvalues.function = GXcopy;
  85    gcvalues.graphics_exposures = False;
  86    XChangeGC(dpy, pdp->gc, GCFunction, &gcvalues);
  87    XChangeGC(dpy, pdp->swapgc, GCFunction, &gcvalues);
  88    XChangeGC(dpy, pdp->swapgc, GCGraphicsExposures, &gcvalues);
  89
  90    /* visual */
  91    visTemp.visualid = visualid;
  92    visMask = VisualIDMask;
  93    pdp->visinfo = XGetVisualInfo(dpy, visMask, &visTemp, &num_visuals);
  94
  95    if (!pdp->visinfo || num_visuals == 0)
  96       return False;
  97
  98    /* create XImage */
  99    pdp->ximage = XCreateImage(dpy,
 100                               pdp->visinfo->visual,
 101                               pdp->visinfo->depth,
 102                               ZPixmap, 0,             /* format, offset */
 103                               NULL,                   /* data */
 104                               0, 0,                   /* width, height */
 105                               32,                     /* bitmap_pad */
 106                               0);                     /* bytes_per_line */
 107
 108   /**
 109    * swrast does not handle 24-bit depth with 24 bpp, so let X do the
 110    * the conversion for us.
 111    */
 112   if (pdp->ximage->bits_per_pixel == 24)
 113      pdp->ximage->bits_per_pixel = 32;
 114
 115    return True;
 116 }
 117
 118 static void
 119 XDestroyDrawable(struct drisw_drawable * pdp, Display * dpy, XID drawable)
 120 {
 121    XDestroyImage(pdp->ximage);
 122    free(pdp->visinfo);
 123
 124    XFreeGC(dpy, pdp->gc);
 125    XFreeGC(dpy, pdp->swapgc);
 126 }
 127
 128 /**
 129  * swrast loader functions
 130  */
 131
 132 static void
 133 swrastGetDrawableInfo(__DRIdrawable * draw,
 134                       int *x, int *y, int *w, int *h,
 135                       void *loaderPrivate)
 136 {
 137    struct drisw_drawable *pdp = loaderPrivate;
 138    __GLXDRIdrawable *pdraw = &(pdp->base);
 139    Display *dpy = pdraw->psc->dpy;
 140    Drawable drawable;
 141
 142    Window root;
 143    unsigned uw, uh, bw, depth;
 144
 145    drawable = pdraw->xDrawable;
 146
 147    XGetGeometry(dpy, drawable, &root, x, y, &uw, &uh, &bw, &depth);
 148    *w = uw;
 149    *h = uh;
 150 }
 151
 152 /**
 153  * Align renderbuffer pitch.
 154  *
 155  * This should be chosen by the driver and the loader (libGL, xserver/glx)
 156  * should use the driver provided pitch.
 157  *
 158  * It seems that the xorg loader (that is the xserver loading swrast_dri for
 159  * indirect rendering, not client-side libGL) requires that the pitch is
 160  * exactly the image width padded to 32 bits. XXX
 161  *
 162  * The above restriction can probably be overcome by using ScratchPixmap and
 163  * CopyArea in the xserver, similar to ShmPutImage, and setting the width of
 164  * the scratch pixmap to 'pitch / cpp'.
 165  */
 166 static inline int
 167 bytes_per_line(unsigned pitch_bits, unsigned mul)
 168 {
 169    unsigned mask = mul - 1;
 170
 171    return ((pitch_bits + mask) & ~mask) / 8;
 172 }
 173
 174 static void
 175 swrastPutImage2(__DRIdrawable * draw, int op,
 176                 int x, int y, int w, int h, int stride,
 177                 char *data, void *loaderPrivate)
 178 {
 179    struct drisw_drawable *pdp = loaderPrivate;
 180    __GLXDRIdrawable *pdraw = &(pdp->base);
 181    Display *dpy = pdraw->psc->dpy;
 182    Drawable drawable;
 183    XImage *ximage;
 184    GC gc;
 185
 186    switch (op) {
 187    case __DRI_SWRAST_IMAGE_OP_DRAW:
 188       gc = pdp->gc;
 189       break;
 190    case __DRI_SWRAST_IMAGE_OP_SWAP:
 191       gc = pdp->swapgc;
 192       break;
 193    default:
 194       return;
 195    }
 196
 197    drawable = pdraw->xDrawable;
 198
 199    ximage = pdp->ximage;
 200    ximage->data = data;
 201    ximage->width = w;
 202    ximage->height = h;
 203    ximage->bytes_per_line = stride ? stride : bytes_per_line(w * ximage->bits_per_pixel, 32);
 204
 205    XPutImage(dpy, drawable, gc, ximage, 0, 0, x, y, w, h);
 206
 207    ximage->data = NULL;
 208 }
 209
 210 static void
 211 swrastPutImage(__DRIdrawable * draw, int op,
 212                int x, int y, int w, int h,
 213                char *data, void *loaderPrivate)
 214 {
 215    swrastPutImage2(draw, op, x, y, w, h, 0, data, loaderPrivate);
 216 }
 217
 218 static void
 219 swrastGetImage(__DRIdrawable * read,
 220                int x, int y, int w, int h,
 221                char *data, void *loaderPrivate)
 222 {
 223    struct drisw_drawable *prp = loaderPrivate;
 224    __GLXDRIdrawable *pread = &(prp->base);
 225    Display *dpy = pread->psc->dpy;
 226    Drawable readable;
 227    XImage *ximage;
 228
 229    readable = pread->xDrawable;
 230
 231    ximage = prp->ximage;
 232    ximage->data = data;
 233    ximage->width = w;
 234    ximage->height = h;
 235    ximage->bytes_per_line = bytes_per_line(w * ximage->bits_per_pixel, 32);
 236
 237    XGetSubImage(dpy, readable, x, y, w, h, ~0L, ZPixmap, ximage, 0, 0);
 238
 239    ximage->data = NULL;
 240 }
 241
 242 static const __DRIswrastLoaderExtension swrastLoaderExtension = {
 243    .base = {__DRI_SWRAST_LOADER, 2 },
 244
 245    .getDrawableInfo     = swrastGetDrawableInfo,
 246    .putImage            = swrastPutImage,
 247    .getImage            = swrastGetImage,
 248    .putImage2           = swrastPutImage2,
 249 };
 250
 251 static const __DRIextension *loader_extensions[] = {
 252    &systemTimeExtension.base,
 253    &swrastLoaderExtension.base,
 254    NULL
 255 };
 256
 257 /**
 258  * GLXDRI functions
 259  */
 260
 261 static void
 262 drisw_destroy_context(struct glx_context *context)
 263 {
 264    struct drisw_context *pcp = (struct drisw_context *) context;
 265    struct drisw_screen *psc = (struct drisw_screen *) context->psc;
 266
 267    driReleaseDrawables(&pcp->base);
 268
 269    free((char *) context->extensions);
 270
 271    (*psc->core->destroyContext) (pcp->driContext);
 272
 273    free(pcp);
 274 }
 275
 276 static int
 277 drisw_bind_context(struct glx_context *context, struct glx_context *old,
 278                    GLXDrawable draw, GLXDrawable read)
 279 {
 280    struct drisw_context *pcp = (struct drisw_context *) context;
 281    struct drisw_screen *psc = (struct drisw_screen *) pcp->base.psc;
 282    struct drisw_drawable *pdraw, *pread;
 283
 284    pdraw = (struct drisw_drawable *) driFetchDrawable(context, draw);
 285    pread = (struct drisw_drawable *) driFetchDrawable(context, read);
 286
 287    driReleaseDrawables(&pcp->base);
 288
 289    if (pdraw == NULL || pread == NULL)
 290       return GLXBadDrawable;
 291
 292    if ((*psc->core->bindContext) (pcp->driContext,
 293                                   pdraw->driDrawable, pread->driDrawable))
 294       return Success;
 295
 296    return GLXBadContext;
 297 }
 298
 299 static void
 300 drisw_unbind_context(struct glx_context *context, struct glx_context *new)
 301 {
 302    struct drisw_context *pcp = (struct drisw_context *) context;
 303    struct drisw_screen *psc = (struct drisw_screen *) pcp->base.psc;
 304
 305    (*psc->core->unbindContext) (pcp->driContext);
 306 }
 307
 308 static void
 309 drisw_bind_tex_image(Display * dpy,
 310                     GLXDrawable drawable,
 311                     int buffer, const int *attrib_list)
 312 {
 313    struct glx_context *gc = __glXGetCurrentContext();
 314    struct drisw_context *pcp = (struct drisw_context *) gc;
 315    __GLXDRIdrawable *base = GetGLXDRIDrawable(dpy, drawable);
 316    struct drisw_drawable *pdraw = (struct drisw_drawable *) base;
 317    struct drisw_screen *psc;
 318
 319    __glXInitialize(dpy);
 320
 321    if (pdraw != NULL) {
 322       psc = (struct drisw_screen *) base->psc;
 323
 324       if (!psc->texBuffer)
 325          return;
 326
 327       if (psc->texBuffer->base.version >= 2 &&
 328         psc->texBuffer->setTexBuffer2 != NULL) {
 329               (*psc->texBuffer->setTexBuffer2) (pcp->driContext,
 330                                            pdraw->base.textureTarget,
 331                                            pdraw->base.textureFormat,
 332                                            pdraw->driDrawable);
 333       }
 334       else {
 335               (*psc->texBuffer->setTexBuffer) (pcp->driContext,
 336                                           pdraw->base.textureTarget,
 337                                           pdraw->driDrawable);
 338       }
 339    }
 340 }
 341
 342 static void
 343 drisw_release_tex_image(Display * dpy, GLXDrawable drawable, int buffer)
 344 {
 345 #if __DRI_TEX_BUFFER_VERSION >= 3
 346    struct glx_context *gc = __glXGetCurrentContext();
 347    struct dri2_context *pcp = (struct dri2_context *) gc;
 348    __GLXDRIdrawable *base = GetGLXDRIDrawable(dpy, drawable);
 349    struct glx_display *dpyPriv = __glXInitialize(dpy);
 350    struct dri2_drawable *pdraw = (struct dri2_drawable *) base;
 351    struct dri2_screen *psc;
 352
 353    if (pdraw != NULL) {
 354       psc = (struct dri2_screen *) base->psc;
 355
 356       if (!psc->texBuffer)
 357          return;
 358
 359       if (psc->texBuffer->base.version >= 3 &&
 360           psc->texBuffer->releaseTexBuffer != NULL) {
 361          (*psc->texBuffer->releaseTexBuffer) (pcp->driContext,
 362                                            pdraw->base.textureTarget,
 363                                            pdraw->driDrawable);
 364       }
 365    }
 366 #endif
 367 }
 368
 369 static const struct glx_context_vtable drisw_context_vtable = {
 370    drisw_destroy_context,
 371    drisw_bind_context,
 372    drisw_unbind_context,
 373    NULL,
 374    NULL,
 375    DRI_glXUseXFont,
 376    drisw_bind_tex_image,
 377    drisw_release_tex_image,
 378    NULL, /* get_proc_address */
 379 };
 380
 381 static struct glx_context *
 382 drisw_create_context(struct glx_screen *base,
 383                      struct glx_config *config_base,
 384                      struct glx_context *shareList, int renderType)
 385 {
 386    struct drisw_context *pcp, *pcp_shared;
 387    __GLXDRIconfigPrivate *config = (__GLXDRIconfigPrivate *) config_base;
 388    struct drisw_screen *psc = (struct drisw_screen *) base;
 389    __DRIcontext *shared = NULL;
 390
 391    if (!psc->base.driScreen)
 392       return NULL;
 393
 394    /* Check the renderType value */
 395    if (!validate_renderType_against_config(config_base, renderType))
 396        return NULL;
 397
 398    if (shareList) {
 399       /* If the shareList context is not a DRISW context, we cannot possibly
 400        * create a DRISW context that shares it.
 401        */
 402       if (shareList->vtable->destroy != drisw_destroy_context) {
 403          return NULL;
 404       }
 405
 406       pcp_shared = (struct drisw_context *) shareList;
 407       shared = pcp_shared->driContext;
 408    }
 409
 410    pcp = calloc(1, sizeof *pcp);
 411    if (pcp == NULL)
 412       return NULL;
 413
 414    if (!glx_context_init(&pcp->base, &psc->base, &config->base)) {
 415       free(pcp);
 416       return NULL;
 417    }
 418
 419    pcp->base.renderType = renderType;
 420
 421    pcp->driContext =
 422       (*psc->core->createNewContext) (psc->driScreen,
 423                                       config->driConfig, shared, pcp);
 424    if (pcp->driContext == NULL) {
 425       free(pcp);
 426       return NULL;
 427    }
 428
 429    pcp->base.vtable = &drisw_context_vtable;
 430
 431    return &pcp->base;
 432 }
 433
 434 static struct glx_context *
 435 drisw_create_context_attribs(struct glx_screen *base,
 436                              struct glx_config *config_base,
 437                              struct glx_context *shareList,
 438                              unsigned num_attribs,
 439                              const uint32_t *attribs,
 440                              unsigned *error)
 441 {
 442    struct drisw_context *pcp, *pcp_shared;
 443    __GLXDRIconfigPrivate *config = (__GLXDRIconfigPrivate *) config_base;
 444    struct drisw_screen *psc = (struct drisw_screen *) base;
 445    __DRIcontext *shared = NULL;
 446
 447    uint32_t minor_ver;
 448    uint32_t major_ver;
 449    uint32_t renderType;
 450    uint32_t flags;
 451    unsigned api;
 452    int reset;
 453    uint32_t ctx_attribs[2 * 4];
 454    unsigned num_ctx_attribs = 0;
 455
 456    if (!psc->base.driScreen)
 457       return NULL;
 458
 459    if (psc->swrast->base.version < 3)
 460       return NULL;
 461
 462    /* Remap the GLX tokens to DRI2 tokens.
 463     */
 464    if (!dri2_convert_glx_attribs(num_attribs, attribs,
 465                                  &major_ver, &minor_ver, &renderType, &flags,
 466                                  &api, &reset, error))
 467       return NULL;
 468
 469    /* Check the renderType value */
 470    if (!validate_renderType_against_config(config_base, renderType)) {
 471        return NULL;
 472    }
 473
 474    if (reset != __DRI_CTX_RESET_NO_NOTIFICATION)
 475       return NULL;
 476
 477    if (shareList) {
 478       pcp_shared = (struct drisw_context *) shareList;
 479       shared = pcp_shared->driContext;
 480    }
 481
 482    pcp = calloc(1, sizeof *pcp);
 483    if (pcp == NULL)
 484       return NULL;
 485
 486    if (!glx_context_init(&pcp->base, &psc->base, &config->base)) {
 487       free(pcp);
 488       return NULL;
 489    }
 490
 491    ctx_attribs[num_ctx_attribs++] = __DRI_CTX_ATTRIB_MAJOR_VERSION;
 492    ctx_attribs[num_ctx_attribs++] = major_ver;
 493    ctx_attribs[num_ctx_attribs++] = __DRI_CTX_ATTRIB_MINOR_VERSION;
 494    ctx_attribs[num_ctx_attribs++] = minor_ver;
 495
 496    if (flags != 0) {
 497       ctx_attribs[num_ctx_attribs++] = __DRI_CTX_ATTRIB_FLAGS;
 498
 499       /* The current __DRI_CTX_FLAG_* values are identical to the
 500        * GLX_CONTEXT_*_BIT values.
 501        */
 502       ctx_attribs[num_ctx_attribs++] = flags;
 503    }
 504
 505    pcp->base.renderType = renderType;
 506
 507    pcp->driContext =
 508       (*psc->swrast->createContextAttribs) (psc->driScreen,
 509                                             api,
 510                                             config->driConfig,
 511                                             shared,
 512                                             num_ctx_attribs / 2,
 513                                             ctx_attribs,
 514                                             error,
 515                                             pcp);
 516    if (pcp->driContext == NULL) {
 517       free(pcp);
 518       return NULL;
 519    }
 520
 521    pcp->base.vtable = &drisw_context_vtable;
 522
 523    return &pcp->base;
 524 }
 525
 526 static void
 527 driswDestroyDrawable(__GLXDRIdrawable * pdraw)
 528 {
 529    struct drisw_drawable *pdp = (struct drisw_drawable *) pdraw;
 530    struct drisw_screen *psc = (struct drisw_screen *) pdp->base.psc;
 531
 532    (*psc->core->destroyDrawable) (pdp->driDrawable);
 533
 534    XDestroyDrawable(pdp, pdraw->psc->dpy, pdraw->drawable);
 535    free(pdp);
 536 }
 537
 538 static __GLXDRIdrawable *
 539 driswCreateDrawable(struct glx_screen *base, XID xDrawable,
 540                     GLXDrawable drawable, struct glx_config *modes)
 541 {
 542    struct drisw_drawable *pdp;
 543    __GLXDRIconfigPrivate *config = (__GLXDRIconfigPrivate *) modes;
 544    struct drisw_screen *psc = (struct drisw_screen *) base;
 545    Bool ret;
 546    const __DRIswrastExtension *swrast = psc->swrast;
 547
 548    pdp = calloc(1, sizeof(*pdp));
 549    if (!pdp)
 550       return NULL;
 551
 552    pdp->base.xDrawable = xDrawable;
 553    pdp->base.drawable = drawable;
 554    pdp->base.psc = &psc->base;
 555
 556    ret = XCreateDrawable(pdp, psc->base.dpy, xDrawable, modes->visualID);
 557    if (!ret) {
 558       free(pdp);
 559       return NULL;
 560    }
 561
 562    /* Create a new drawable */
 563    pdp->driDrawable =
 564       (*swrast->createNewDrawable) (psc->driScreen, config->driConfig, pdp);
 565
 566    if (!pdp->driDrawable) {
 567       XDestroyDrawable(pdp, psc->base.dpy, xDrawable);
 568       free(pdp);
 569       return NULL;
 570    }
 571
 572    pdp->base.destroyDrawable = driswDestroyDrawable;
 573
 574    return &pdp->base;
 575 }
 576
 577 static int64_t
 578 driswSwapBuffers(__GLXDRIdrawable * pdraw,
 579                  int64_t target_msc, int64_t divisor, int64_t remainder,
 580                  Bool flush)
 581 {
 582    struct drisw_drawable *pdp = (struct drisw_drawable *) pdraw;
 583    struct drisw_screen *psc = (struct drisw_screen *) pdp->base.psc;
 584
 585    (void) target_msc;
 586    (void) divisor;
 587    (void) remainder;
 588
 589    if (flush) {
 590       glFlush();
 591    }
 592
 593    (*psc->core->swapBuffers) (pdp->driDrawable);
 594
 595    return 0;
 596 }
 597
 598 static void
 599 driswCopySubBuffer(__GLXDRIdrawable * pdraw,
 600                    int x, int y, int width, int height, Bool flush)
 601 {
 602    struct drisw_drawable *pdp = (struct drisw_drawable *) pdraw;
 603    struct drisw_screen *psc = (struct drisw_screen *) pdp->base.psc;
 604
 605    if (flush) {
 606       glFlush();
 607    }
 608
 609    (*psc->copySubBuffer->copySubBuffer) (pdp->driDrawable,
 610                                             x, y, width, height);
 611 }
 612
 613 static void
 614 driswDestroyScreen(struct glx_screen *base)
 615 {
 616    struct drisw_screen *psc = (struct drisw_screen *) base;
 617
 618    /* Free the direct rendering per screen data */
 619    (*psc->core->destroyScreen) (psc->driScreen);
 620    driDestroyConfigs(psc->driver_configs);
 621    psc->driScreen = NULL;
 622    if (psc->driver)
 623       dlclose(psc->driver);
 624 }
 625
 626 #define SWRAST_DRIVER_NAME "swrast"
 627
 628 static void *
 629 driOpenSwrast(void)
 630 {
 631    void *driver = NULL;
 632
 633    if (driver == NULL)
 634       driver = driOpenDriver(SWRAST_DRIVER_NAME);
 635
 636    return driver;
 637 }
 638
 639 static const struct glx_screen_vtable drisw_screen_vtable = {
 640    drisw_create_context,
 641    drisw_create_context_attribs
 642 };
 643
 644 static void
 645 driswBindExtensions(struct drisw_screen *psc, const __DRIextension **extensions)
 646 {
 647    int i;
 648
 649    __glXEnableDirectExtension(&psc->base, "GLX_SGI_make_current_read");
 650
 651    if (psc->swrast->base.version >= 3) {
 652       __glXEnableDirectExtension(&psc->base, "GLX_ARB_create_context");
 653       __glXEnableDirectExtension(&psc->base, "GLX_ARB_create_context_profile");
 654
 655       /* DRISW version >= 2 implies support for OpenGL ES 2.0.
 656        */
 657       __glXEnableDirectExtension(&psc->base,
 658                                  "GLX_EXT_create_context_es2_profile");
 659    }
 660
 661    if (psc->copySubBuffer)
 662       __glXEnableDirectExtension(&psc->base, "GLX_MESA_copy_sub_buffer");
 663
 664    /* FIXME: Figure out what other extensions can be ported here from dri2. */
 665    for (i = 0; extensions[i]; i++) {
 666       if ((strcmp(extensions[i]->name, __DRI_TEX_BUFFER) == 0)) {
 667          psc->texBuffer = (__DRItexBufferExtension *) extensions[i];
 668          __glXEnableDirectExtension(&psc->base, "GLX_EXT_texture_from_pixmap");
 669       }
 670    }
 671 }
 672
 673 static struct glx_screen *
 674 driswCreateScreen(int screen, struct glx_display *priv)
 675 {
 676    __GLXDRIscreen *psp;
 677    const __DRIconfig **driver_configs;
 678    const __DRIextension **extensions;
 679    struct drisw_screen *psc;
 680    struct glx_config *configs = NULL, *visuals = NULL;
 681    int i;
 682
 683    psc = calloc(1, sizeof *psc);
 684    if (psc == NULL)
 685       return NULL;
 686
 687    if (!glx_screen_init(&psc->base, screen, priv)) {
 688       free(psc);
 689       return NULL;
 690    }
 691
 692    psc->driver = driOpenSwrast();
 693    if (psc->driver == NULL)
 694       goto handle_error;
 695
 696    extensions = driGetDriverExtensions(psc->driver, SWRAST_DRIVER_NAME);
 697    if (extensions == NULL)
 698       goto handle_error;
 699
 700    for (i = 0; extensions[i]; i++) {
 701       if (strcmp(extensions[i]->name, __DRI_CORE) == 0)
 702          psc->core = (__DRIcoreExtension *) extensions[i];
 703       if (strcmp(extensions[i]->name, __DRI_SWRAST) == 0)
 704          psc->swrast = (__DRIswrastExtension *) extensions[i];
 705       if (strcmp(extensions[i]->name, __DRI_COPY_SUB_BUFFER) == 0)
 706          psc->copySubBuffer = (__DRIcopySubBufferExtension *) extensions[i];
 707    }
 708
 709    if (psc->core == NULL || psc->swrast == NULL) {
 710       ErrorMessageF("core dri extension not found\n");
 711       goto handle_error;
 712    }
 713
 714    if (psc->swrast->base.version >= 4) {
 715       psc->driScreen =
 716          psc->swrast->createNewScreen2(screen, loader_extensions,
 717                                        extensions,
 718                                        &driver_configs, psc);
 719    } else {
 720       psc->driScreen =
 721          psc->swrast->createNewScreen(screen, loader_extensions,
 722                                       &driver_configs, psc);
 723    }
 724    if (psc->driScreen == NULL) {
 725       ErrorMessageF("failed to create dri screen\n");
 726       goto handle_error;
 727    }
 728
 729    extensions = psc->core->getExtensions(psc->driScreen);
 730    driswBindExtensions(psc, extensions);
 731
 732    configs = driConvertConfigs(psc->core, psc->base.configs, driver_configs);
 733    visuals = driConvertConfigs(psc->core, psc->base.visuals, driver_configs);
 734
 735    if (!configs || !visuals)
 736        goto handle_error;
 737
 738    glx_config_destroy_list(psc->base.configs);
 739    psc->base.configs = configs;
 740    glx_config_destroy_list(psc->base.visuals);
 741    psc->base.visuals = visuals;
 742
 743    psc->driver_configs = driver_configs;
 744
 745    psc->base.vtable = &drisw_screen_vtable;
 746    psp = &psc->vtable;
 747    psc->base.driScreen = psp;
 748    psp->destroyScreen = driswDestroyScreen;
 749    psp->createDrawable = driswCreateDrawable;
 750    psp->swapBuffers = driswSwapBuffers;
 751
 752    if (psc->copySubBuffer)
 753       psp->copySubBuffer = driswCopySubBuffer;
 754
 755    return &psc->base;
 756
 757  handle_error:
 758    if (configs)
 759        glx_config_destroy_list(configs);
 760    if (visuals)
 761        glx_config_destroy_list(visuals);
 762    if (psc->driScreen)
 763        psc->core->destroyScreen(psc->driScreen);
 764    psc->driScreen = NULL;
 765
 766    if (psc->driver)
 767       dlclose(psc->driver);
 768    glx_screen_cleanup(&psc->base);
 769    free(psc);
 770
 771    CriticalErrorMessageF("failed to load driver: %s\n", SWRAST_DRIVER_NAME);
 772
 773    return NULL;
 774 }
 775
 776 /* Called from __glXFreeDisplayPrivate.
 777  */
 778 static void
 779 driswDestroyDisplay(__GLXDRIdisplay * dpy)
 780 {
 781    free(dpy);
 782 }
 783
 784 /*
 785  * Allocate, initialize and return a __DRIdisplayPrivate object.
 786  * This is called from __glXInitialize() when we are given a new
 787  * display pointer.
 788  */
 789 _X_HIDDEN __GLXDRIdisplay *
 790 driswCreateDisplay(Display * dpy)
 791 {
 792    struct drisw_display *pdpyp;
 793
 794    pdpyp = malloc(sizeof *pdpyp);
 795    if (pdpyp == NULL)
 796       return NULL;
 797
 798    pdpyp->base.destroyDisplay = driswDestroyDisplay;
 799    pdpyp->base.createScreen = driswCreateScreen;
 800
 801    return &pdpyp->base;
 802 }
 803
 804 #endif /* GLX_DIRECT_RENDERING */