src/egl/main/eglcontext.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2008 VMware, Inc.
   4  * Copyright 2009-2010 Chia-I Wu <olvaffe@gmail.com>
   5  * Copyright 2010-2011 LunarG, Inc.
   6  * All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the
  10  * "Software"), to deal in the Software without restriction, including
  11  * without limitation the rights to use, copy, modify, merge, publish,
  12  * distribute, sub license, and/or sell copies of the Software, and to
  13  * permit persons to whom the Software is furnished to do so, subject to
  14  * the following conditions:
  15  *
  16  * The above copyright notice and this permission notice (including the
  17  * next paragraph) shall be included in all copies or substantial portions
  18  * of the Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  23  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  25  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  26  * DEALINGS IN THE SOFTWARE.
  27  *
  28  **************************************************************************/
  29
  30
  31 #include <assert.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include "eglconfig.h"
  35 #include "eglcontext.h"
  36 #include "egldisplay.h"
  37 #include "eglcurrent.h"
  38 #include "eglsurface.h"
  39 #include "egllog.h"
  40
  41
  42 /**
  43  * Return the API bit (one of EGL_xxx_BIT) of the context.
  44  */
  45 static EGLint
  46 _eglGetContextAPIBit(_EGLContext *ctx)
  47 {
  48    EGLint bit = 0;
  49
  50    switch (ctx->ClientAPI) {
  51    case EGL_OPENGL_ES_API:
  52       switch (ctx->ClientMajorVersion) {
  53       case 1:
  54          bit = EGL_OPENGL_ES_BIT;
  55          break;
  56       case 2:
  57          bit = EGL_OPENGL_ES2_BIT;
  58          break;
  59       case 3:
  60          bit = EGL_OPENGL_ES3_BIT_KHR;
  61          break;
  62       default:
  63          break;
  64       }
  65       break;
  66    case EGL_OPENVG_API:
  67       bit = EGL_OPENVG_BIT;
  68       break;
  69    case EGL_OPENGL_API:
  70       bit = EGL_OPENGL_BIT;
  71       break;
  72    default:
  73       break;
  74    }
  75
  76    return bit;
  77 }
  78
  79
  80 /**
  81  * Parse the list of context attributes and return the proper error code.
  82  */
  83 static EGLint
  84 _eglParseContextAttribList(_EGLContext *ctx, _EGLDisplay *dpy,
  85                            const EGLint *attrib_list)
  86 {
  87    EGLenum api = ctx->ClientAPI;
  88    EGLint i, err = EGL_SUCCESS;
  89
  90    if (!attrib_list)
  91       return EGL_SUCCESS;
  92
  93    if (api == EGL_OPENVG_API && attrib_list[0] != EGL_NONE) {
  94       _eglLog(_EGL_DEBUG, "bad context attribute 0x%04x", attrib_list[0]);
  95       return EGL_BAD_ATTRIBUTE;
  96    }
  97
  98    for (i = 0; attrib_list[i] != EGL_NONE; i++) {
  99       EGLint attr = attrib_list[i++];
 100       EGLint val = attrib_list[i];
 101
 102       switch (attr) {
 103       case EGL_CONTEXT_CLIENT_VERSION:
 104          ctx->ClientMajorVersion = val;
 105          break;
 106
 107       case EGL_CONTEXT_MINOR_VERSION_KHR:
 108          if (!dpy->Extensions.KHR_create_context) {
 109             err = EGL_BAD_ATTRIBUTE;
 110             break;
 111          }
 112
 113          ctx->ClientMinorVersion = val;
 114          break;
 115
 116       case EGL_CONTEXT_FLAGS_KHR:
 117          if (!dpy->Extensions.KHR_create_context) {
 118             err = EGL_BAD_ATTRIBUTE;
 119             break;
 120          }
 121
 122          /* The EGL_KHR_create_context spec says:
 123           *
 124           *     "Flags are only defined for OpenGL context creation, and
 125           *     specifying a flags value other than zero for other types of
 126           *     contexts, including OpenGL ES contexts, will generate an
 127           *     error."
 128           */
 129          if (api != EGL_OPENGL_API && val != 0) {
 130             err = EGL_BAD_ATTRIBUTE;
 131             break;
 132          }
 133
 134          ctx->Flags = val;
 135          break;
 136
 137       case EGL_CONTEXT_OPENGL_PROFILE_MASK_KHR:
 138          if (!dpy->Extensions.KHR_create_context) {
 139             err = EGL_BAD_ATTRIBUTE;
 140             break;
 141          }
 142
 143          /* The EGL_KHR_create_context spec says:
 144           *
 145           *     "[EGL_CONTEXT_OPENGL_PROFILE_MASK_KHR] is only meaningful for
 146           *     OpenGL contexts, and specifying it for other types of
 147           *     contexts, including OpenGL ES contexts, will generate an
 148           *     error."
 149           */
 150          if (api != EGL_OPENGL_API) {
 151             err = EGL_BAD_ATTRIBUTE;
 152             break;
 153          }
 154
 155          ctx->Profile = val;
 156          break;
 157
 158       case EGL_CONTEXT_OPENGL_RESET_NOTIFICATION_STRATEGY_KHR:
 159          /* The EGL_KHR_create_context spec says:
 160           *
 161           *     "[EGL_CONTEXT_OPENGL_RESET_NOTIFICATION_STRATEGY_KHR] is only
 162           *     meaningful for OpenGL contexts, and specifying it for other
 163           *     types of contexts, including OpenGL ES contexts, will generate
 164           *     an error."
 165           */
 166            if (!dpy->Extensions.KHR_create_context
 167                || api != EGL_OPENGL_API) {
 168             err = EGL_BAD_ATTRIBUTE;
 169             break;
 170          }
 171
 172          ctx->ResetNotificationStrategy = val;
 173          break;
 174
 175       case EGL_CONTEXT_OPENGL_RESET_NOTIFICATION_STRATEGY_EXT:
 176          /* The EGL_EXT_create_context_robustness spec says:
 177           *
 178           *     "[EGL_CONTEXT_OPENGL_RESET_NOTIFICATION_STRATEGY_EXT] is only
 179           *     meaningful for OpenGL ES contexts, and specifying it for other
 180           *     types of contexts will generate an EGL_BAD_ATTRIBUTE error."
 181           */
 182          if (!dpy->Extensions.EXT_create_context_robustness
 183              || api != EGL_OPENGL_ES_API) {
 184             err = EGL_BAD_ATTRIBUTE;
 185             break;
 186          }
 187
 188          ctx->ResetNotificationStrategy = val;
 189          break;
 190
 191       case EGL_CONTEXT_OPENGL_ROBUST_ACCESS_EXT:
 192          if (!dpy->Extensions.EXT_create_context_robustness) {
 193             err = EGL_BAD_ATTRIBUTE;
 194             break;
 195          }
 196
 197          ctx->Flags = EGL_CONTEXT_OPENGL_ROBUST_ACCESS_BIT_KHR;
 198          break;
 199
 200       default:
 201          err = EGL_BAD_ATTRIBUTE;
 202          break;
 203       }
 204
 205       if (err != EGL_SUCCESS) {
 206          _eglLog(_EGL_DEBUG, "bad context attribute 0x%04x", attr);
 207          break;
 208       }
 209    }
 210
 211    if (api == EGL_OPENGL_API) {
 212       /* The EGL_KHR_create_context spec says:
 213        *
 214        *     "If the requested OpenGL version is less than 3.2,
 215        *     EGL_CONTEXT_OPENGL_PROFILE_MASK_KHR is ignored and the
 216        *     functionality of the context is determined solely by the
 217        *     requested version."
 218        *
 219        * Since the value is ignored, only validate the setting if the version
 220        * is >= 3.2.
 221        */
 222       if (ctx->ClientMajorVersion >= 4
 223           || (ctx->ClientMajorVersion == 3 && ctx->ClientMinorVersion >= 2)) {
 224          switch (ctx->Profile) {
 225          case EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT_KHR:
 226          case EGL_CONTEXT_OPENGL_COMPATIBILITY_PROFILE_BIT_KHR:
 227             break;
 228
 229          default:
 230             /* The EGL_KHR_create_context spec says:
 231              *
 232              *     "* If an OpenGL context is requested, the requested version
 233              *        is greater than 3.2, and the value for attribute
 234              *        EGL_CONTEXT_OPENGL_PROFILE_MASK_KHR has no bits set; has
 235              *        any bits set other than EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT_KHR
 236              *        and EGL_CONTEXT_OPENGL_COMPATIBILITY_PROFILE_BIT_KHR; has
 237              *        more than one of these bits set; or if the implementation does
 238              *        not support the requested profile, then an EGL_BAD_MATCH error
 239              *        is generated."
 240              */
 241             err = EGL_BAD_MATCH;
 242             break;
 243          }
 244       }
 245
 246       /* The EGL_KHR_create_context spec says:
 247        *
 248        *     "* If an OpenGL context is requested and the values for
 249        *        attributes EGL_CONTEXT_MAJOR_VERSION_KHR and
 250        *        EGL_CONTEXT_MINOR_VERSION_KHR, when considered together with
 251        *        the value for attribute
 252        *        EGL_CONTEXT_FORWARD_COMPATIBLE_BIT_KHR, specify an OpenGL
 253        *        version and feature set that are not defined, than an
 254        *        EGL_BAD_MATCH error is generated.
 255        *
 256        *        ... Thus, examples of invalid combinations of attributes
 257        *        include:
 258        *
 259        *          - Major version < 1 or > 4
 260        *          - Major version == 1 and minor version < 0 or > 5
 261        *          - Major version == 2 and minor version < 0 or > 1
 262        *          - Major version == 3 and minor version < 0 or > 2
 263        *          - Major version == 4 and minor version < 0 or > 2
 264        *          - Forward-compatible flag set and major version < 3"
 265        */
 266       if (ctx->ClientMajorVersion < 1 || ctx->ClientMinorVersion < 0)
 267          err = EGL_BAD_MATCH;
 268
 269       switch (ctx->ClientMajorVersion) {
 270       case 1:
 271          if (ctx->ClientMinorVersion > 5
 272              || (ctx->Flags & EGL_CONTEXT_OPENGL_FORWARD_COMPATIBLE_BIT_KHR) != 0)
 273             err = EGL_BAD_MATCH;
 274          break;
 275
 276       case 2:
 277          if (ctx->ClientMinorVersion > 1
 278              || (ctx->Flags & EGL_CONTEXT_OPENGL_FORWARD_COMPATIBLE_BIT_KHR) != 0)
 279             err = EGL_BAD_MATCH;
 280          break;
 281
 282       case 3:
 283          /* Note: The text above is incorrect.  There *is* an OpenGL 3.3!
 284           */
 285          if (ctx->ClientMinorVersion > 3)
 286             err = EGL_BAD_MATCH;
 287          break;
 288
 289       case 4:
 290       default:
 291          /* Don't put additional version checks here.  We don't know that
 292           * there won't be versions > 4.2.
 293           */
 294          break;
 295       }
 296    } else if (api == EGL_OPENGL_ES_API) {
 297       /* The EGL_KHR_create_context spec says:
 298        *
 299        *     "* If an OpenGL ES context is requested and the values for
 300        *        attributes EGL_CONTEXT_MAJOR_VERSION_KHR and
 301        *        EGL_CONTEXT_MINOR_VERSION_KHR specify an OpenGL ES version that
 302        *        is not defined, than an EGL_BAD_MATCH error is generated.
 303        *
 304        *        ... Examples of invalid combinations of attributes include:
 305        *
 306        *          - Major version < 1 or > 2
 307        *          - Major version == 1 and minor version < 0 or > 1
 308        *          - Major version == 2 and minor version != 0
 309        */
 310       if (ctx->ClientMajorVersion < 1 || ctx->ClientMinorVersion < 0)
 311          err = EGL_BAD_MATCH;
 312
 313       switch (ctx->ClientMajorVersion) {
 314       case 1:
 315          if (ctx->ClientMinorVersion > 1)
 316             err = EGL_BAD_MATCH;
 317          break;
 318
 319       case 2:
 320          if (ctx->ClientMinorVersion > 0)
 321             err = EGL_BAD_MATCH;
 322          break;
 323
 324       case 3:
 325          /* Don't put additional version checks here.  We don't know that
 326           * there won't be versions > 3.0.
 327           */
 328          break;
 329
 330       default:
 331          err = EGL_BAD_MATCH;
 332          break;
 333       }
 334    }
 335
 336    switch (ctx->ResetNotificationStrategy) {
 337    case EGL_NO_RESET_NOTIFICATION_KHR:
 338    case EGL_LOSE_CONTEXT_ON_RESET_KHR:
 339       break;
 340
 341    default:
 342       err = EGL_BAD_ATTRIBUTE;
 343       break;
 344    }
 345
 346    if ((ctx->Flags & ~(EGL_CONTEXT_OPENGL_DEBUG_BIT_KHR
 347                       | EGL_CONTEXT_OPENGL_FORWARD_COMPATIBLE_BIT_KHR
 348                       | EGL_CONTEXT_OPENGL_ROBUST_ACCESS_BIT_KHR)) != 0) {
 349       err = EGL_BAD_ATTRIBUTE;
 350    }
 351
 352    return err;
 353 }
 354
 355
 356 /**
 357  * Initialize the given _EGLContext object to defaults and/or the values
 358  * in the attrib_list.
 359  */
 360 EGLBoolean
 361 _eglInitContext(_EGLContext *ctx, _EGLDisplay *dpy, _EGLConfig *conf,
 362                 const EGLint *attrib_list)
 363 {
 364    const EGLenum api = eglQueryAPI();
 365    EGLint err;
 366
 367    if (api == EGL_NONE) {
 368       _eglError(EGL_BAD_MATCH, "eglCreateContext(no client API)");
 369       return EGL_FALSE;
 370    }
 371
 372    _eglInitResource(&ctx->Resource, sizeof(*ctx), dpy);
 373    ctx->ClientAPI = api;
 374    ctx->Config = conf;
 375    ctx->WindowRenderBuffer = EGL_NONE;
 376    ctx->Profile = EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT_KHR;
 377
 378    ctx->ClientMajorVersion = 1; /* the default, per EGL spec */
 379    ctx->ClientMinorVersion = 0;
 380    ctx->Flags = 0;
 381    ctx->Profile = EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT_KHR;
 382    ctx->ResetNotificationStrategy = EGL_NO_RESET_NOTIFICATION_KHR;
 383
 384    err = _eglParseContextAttribList(ctx, dpy, attrib_list);
 385    if (err == EGL_SUCCESS && ctx->Config) {
 386       EGLint api_bit;
 387
 388       api_bit = _eglGetContextAPIBit(ctx);
 389       if (!(ctx->Config->RenderableType & api_bit)) {
 390          _eglLog(_EGL_DEBUG, "context api is 0x%x while config supports 0x%x",
 391                api_bit, ctx->Config->RenderableType);
 392          err = EGL_BAD_CONFIG;
 393       }
 394    }
 395    if (err != EGL_SUCCESS)
 396       return _eglError(err, "eglCreateContext");
 397
 398    return EGL_TRUE;
 399 }
 400
 401
 402 static EGLint
 403 _eglQueryContextRenderBuffer(_EGLContext *ctx)
 404 {
 405    _EGLSurface *surf = ctx->DrawSurface;
 406    EGLint rb;
 407
 408    if (!surf)
 409       return EGL_NONE;
 410    if (surf->Type == EGL_WINDOW_BIT && ctx->WindowRenderBuffer != EGL_NONE)
 411       rb = ctx->WindowRenderBuffer;
 412    else
 413       rb = surf->RenderBuffer;
 414    return rb;
 415 }
 416
 417
 418 EGLBoolean
 419 _eglQueryContext(_EGLDriver *drv, _EGLDisplay *dpy, _EGLContext *c,
 420                  EGLint attribute, EGLint *value)
 421 {
 422    (void) drv;
 423    (void) dpy;
 424
 425    if (!value)
 426       return _eglError(EGL_BAD_PARAMETER, "eglQueryContext");
 427
 428    switch (attribute) {
 429    case EGL_CONFIG_ID:
 430       if (!c->Config)
 431          return _eglError(EGL_BAD_ATTRIBUTE, "eglQueryContext");
 432       *value = c->Config->ConfigID;
 433       break;
 434    case EGL_CONTEXT_CLIENT_VERSION:
 435       *value = c->ClientMajorVersion;
 436       break;
 437    case EGL_CONTEXT_CLIENT_TYPE:
 438       *value = c->ClientAPI;
 439       break;
 440    case EGL_RENDER_BUFFER:
 441       *value = _eglQueryContextRenderBuffer(c);
 442       break;
 443    default:
 444       return _eglError(EGL_BAD_ATTRIBUTE, "eglQueryContext");
 445    }
 446
 447    return EGL_TRUE;
 448 }
 449
 450
 451 /**
 452  * Bind the context to the thread and return the previous context.
 453  *
 454  * Note that the context may be NULL.
 455  */
 456 static _EGLContext *
 457 _eglBindContextToThread(_EGLContext *ctx, _EGLThreadInfo *t)
 458 {
 459    EGLint apiIndex;
 460    _EGLContext *oldCtx;
 461
 462    apiIndex = (ctx) ?
 463       _eglConvertApiToIndex(ctx->ClientAPI) : t->CurrentAPIIndex;
 464
 465    oldCtx = t->CurrentContexts[apiIndex];
 466    if (ctx != oldCtx) {
 467       if (oldCtx)
 468          oldCtx->Binding = NULL;
 469       if (ctx)
 470          ctx->Binding = t;
 471
 472       t->CurrentContexts[apiIndex] = ctx;
 473    }
 474
 475    return oldCtx;
 476 }
 477
 478
 479 /**
 480  * Return true if the given context and surfaces can be made current.
 481  */
 482 static EGLBoolean
 483 _eglCheckMakeCurrent(_EGLContext *ctx, _EGLSurface *draw, _EGLSurface *read)
 484 {
 485    _EGLThreadInfo *t = _eglGetCurrentThread();
 486    _EGLDisplay *dpy;
 487    EGLint conflict_api;
 488
 489    if (_eglIsCurrentThreadDummy())
 490       return _eglError(EGL_BAD_ALLOC, "eglMakeCurrent");
 491
 492    /* this is easy */
 493    if (!ctx) {
 494       if (draw || read)
 495          return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
 496       return EGL_TRUE;
 497    }
 498
 499    dpy = ctx->Resource.Display;
 500    if (!dpy->Extensions.KHR_surfaceless_context
 501        && (draw == NULL || read == NULL))
 502       return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
 503
 504    /*
 505     * The spec says
 506     *
 507     * "If ctx is current to some other thread, or if either draw or read are
 508     * bound to contexts in another thread, an EGL_BAD_ACCESS error is
 509     * generated."
 510     *
 511     * and
 512     *
 513     * "at most one context may be bound to a particular surface at a given
 514     * time"
 515     */
 516    if (ctx->Binding && ctx->Binding != t)
 517       return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
 518    if (draw && draw->CurrentContext && draw->CurrentContext != ctx) {
 519       if (draw->CurrentContext->Binding != t ||
 520           draw->CurrentContext->ClientAPI != ctx->ClientAPI)
 521          return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
 522    }
 523    if (read && read->CurrentContext && read->CurrentContext != ctx) {
 524       if (read->CurrentContext->Binding != t ||
 525           read->CurrentContext->ClientAPI != ctx->ClientAPI)
 526          return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
 527    }
 528
 529    /* If the context has a config then it must match that of the two
 530     * surfaces */
 531    if (ctx->Config) {
 532       if ((draw && draw->Config != ctx->Config) ||
 533           (read && read->Config != ctx->Config))
 534          return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
 535    } else {
 536       /* Otherwise we must be using the EGL_MESA_configless_context
 537        * extension */
 538       assert(dpy->Extensions.MESA_configless_context);
 539
 540       /* The extension doesn't permit binding draw and read buffers with
 541        * differing contexts */
 542       if (draw && read && draw->Config != read->Config)
 543          return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
 544    }
 545
 546    switch (ctx->ClientAPI) {
 547    /* OpenGL and OpenGL ES are conflicting */
 548    case EGL_OPENGL_ES_API:
 549       conflict_api = EGL_OPENGL_API;
 550       break;
 551    case EGL_OPENGL_API:
 552       conflict_api = EGL_OPENGL_ES_API;
 553       break;
 554    default:
 555       conflict_api = -1;
 556       break;
 557    }
 558
 559    if (conflict_api >= 0 && _eglGetAPIContext(conflict_api))
 560       return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
 561
 562    return EGL_TRUE;
 563 }
 564
 565
 566 /**
 567  * Bind the context to the current thread and given surfaces.  Return the
 568  * previous bound context and surfaces.  The caller should unreference the
 569  * returned context and surfaces.
 570  *
 571  * Making a second call with the resources returned by the first call
 572  * unsurprisingly undoes the first call, except for the resouce reference
 573  * counts.
 574  */
 575 EGLBoolean
 576 _eglBindContext(_EGLContext *ctx, _EGLSurface *draw, _EGLSurface *read,
 577                 _EGLContext **old_ctx,
 578                 _EGLSurface **old_draw, _EGLSurface **old_read)
 579 {
 580    _EGLThreadInfo *t = _eglGetCurrentThread();
 581    _EGLContext *prev_ctx;
 582    _EGLSurface *prev_draw, *prev_read;
 583
 584    if (!_eglCheckMakeCurrent(ctx, draw, read))
 585       return EGL_FALSE;
 586
 587    /* increment refcounts before binding */
 588    _eglGetContext(ctx);
 589    _eglGetSurface(draw);
 590    _eglGetSurface(read);
 591
 592    /* bind the new context */
 593    prev_ctx = _eglBindContextToThread(ctx, t);
 594
 595    /* break previous bindings */
 596    if (prev_ctx) {
 597       prev_draw = prev_ctx->DrawSurface;
 598       prev_read = prev_ctx->ReadSurface;
 599
 600       if (prev_draw)
 601          prev_draw->CurrentContext = NULL;
 602       if (prev_read)
 603          prev_read->CurrentContext = NULL;
 604
 605       prev_ctx->DrawSurface = NULL;
 606       prev_ctx->ReadSurface = NULL;
 607    }
 608    else {
 609       prev_draw = prev_read = NULL;
 610    }
 611
 612    /* establish new bindings */
 613    if (ctx) {
 614       if (draw)
 615          draw->CurrentContext = ctx;
 616       if (read)
 617          read->CurrentContext = ctx;
 618
 619       ctx->DrawSurface = draw;
 620       ctx->ReadSurface = read;
 621    }
 622
 623    assert(old_ctx && old_draw && old_read);
 624    *old_ctx = prev_ctx;
 625    *old_draw = prev_draw;
 626    *old_read = prev_read;
 627
 628    return EGL_TRUE;
 629 }