src/mesa/main/context.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   5  * Copyright (C) 2008  VMware, Inc.  All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25
  26 /**
  27  * \file context.c
  28  * Mesa context/visual/framebuffer management functions.
  29  * \author Brian Paul
  30  */
  31
  32 /**
  33  * \mainpage Mesa Main Module
  34  *
  35  * \section MainIntroduction Introduction
  36  *
  37  * The Mesa Main module consists of all the files in the main/ directory.
  38  * Among the features of this module are:
  39  * <UL>
  40  * <LI> Structures to represent most GL state </LI>
  41  * <LI> State set/get functions </LI>
  42  * <LI> Display lists </LI>
  43  * <LI> Texture unit, object and image handling </LI>
  44  * <LI> Matrix and attribute stacks </LI>
  45  * </UL>
  46  *
  47  * Other modules are responsible for API dispatch, vertex transformation,
  48  * point/line/triangle setup, rasterization, vertex array caching,
  49  * vertex/fragment programs/shaders, etc.
  50  *
  51  *
  52  * \section AboutDoxygen About Doxygen
  53  *
  54  * If you're viewing this information as Doxygen-generated HTML you'll
  55  * see the documentation index at the top of this page.
  56  *
  57  * The first line lists the Mesa source code modules.
  58  * The second line lists the indexes available for viewing the documentation
  59  * for each module.
  60  *
  61  * Selecting the <b>Main page</b> link will display a summary of the module
  62  * (this page).
  63  *
  64  * Selecting <b>Data Structures</b> will list all C structures.
  65  *
  66  * Selecting the <b>File List</b> link will list all the source files in
  67  * the module.
  68  * Selecting a filename will show a list of all functions defined in that file.
  69  *
  70  * Selecting the <b>Data Fields</b> link will display a list of all
  71  * documented structure members.
  72  *
  73  * Selecting the <b>Globals</b> link will display a list
  74  * of all functions, structures, global variables and macros in the module.
  75  *
  76  */
  77
  78
  79 #include "glheader.h"
  80 #include "imports.h"
  81 #include "accum.h"
  82 #include "api_exec.h"
  83 #include "api_loopback.h"
  84 #include "arrayobj.h"
  85 #include "attrib.h"
  86 #include "bbox.h"
  87 #include "blend.h"
  88 #include "buffers.h"
  89 #include "bufferobj.h"
  90 #include "context.h"
  91 #include "cpuinfo.h"
  92 #include "debug.h"
  93 #include "debug_output.h"
  94 #include "depth.h"
  95 #include "dlist.h"
  96 #include "eval.h"
  97 #include "extensions.h"
  98 #include "fbobject.h"
  99 #include "feedback.h"
 100 #include "fog.h"
 101 #include "formats.h"
 102 #include "framebuffer.h"
 103 #include "glthread.h"
 104 #include "hint.h"
 105 #include "hash.h"
 106 #include "light.h"
 107 #include "lines.h"
 108 #include "macros.h"
 109 #include "matrix.h"
 110 #include "multisample.h"
 111 #include "performance_monitor.h"
 112 #include "performance_query.h"
 113 #include "pipelineobj.h"
 114 #include "pixel.h"
 115 #include "pixelstore.h"
 116 #include "points.h"
 117 #include "polygon.h"
 118 #include "queryobj.h"
 119 #include "syncobj.h"
 120 #include "rastpos.h"
 121 #include "remap.h"
 122 #include "scissor.h"
 123 #include "shared.h"
 124 #include "shaderobj.h"
 125 #include "shaderimage.h"
 126 #include "state.h"
 127 #include "util/debug.h"
 128 #include "util/disk_cache.h"
 129 #include "util/strtod.h"
 130 #include "stencil.h"
 131 #include "texcompress_s3tc.h"
 132 #include "texstate.h"
 133 #include "transformfeedback.h"
 134 #include "mtypes.h"
 135 #include "varray.h"
 136 #include "version.h"
 137 #include "viewport.h"
 138 #include "texturebindless.h"
 139 #include "program/program.h"
 140 #include "math/m_matrix.h"
 141 #include "main/dispatch.h" /* for _gloffset_COUNT */
 142 #include "macros.h"
 143 #include "git_sha1.h"
 144
 145 #ifdef USE_SPARC_ASM
 146 #include "sparc/sparc.h"
 147 #endif
 148
 149 #include "compiler/glsl_types.h"
 150 #include "compiler/glsl/glsl_parser_extras.h"
 151 #include <stdbool.h>
 152
 153
 154 #ifndef MESA_VERBOSE
 155 int MESA_VERBOSE = 0;
 156 #endif
 157
 158 #ifndef MESA_DEBUG_FLAGS
 159 int MESA_DEBUG_FLAGS = 0;
 160 #endif
 161
 162
 163 /* ubyte -> float conversion */
 164 GLfloat _mesa_ubyte_to_float_color_tab[256];
 165
 166
 167
 168 /**
 169  * Swap buffers notification callback.
 170  *
 171  * \param ctx GL context.
 172  *
 173  * Called by window system just before swapping buffers.
 174  * We have to finish any pending rendering.
 175  */
 176 void
 177 _mesa_notifySwapBuffers(struct gl_context *ctx)
 178 {
 179    if (MESA_VERBOSE & VERBOSE_SWAPBUFFERS)
 180       _mesa_debug(ctx, "SwapBuffers\n");
 181    FLUSH_CURRENT( ctx, 0 );
 182    if (ctx->Driver.Flush) {
 183       ctx->Driver.Flush(ctx);
 184    }
 185 }
 186
 187
 188 /**********************************************************************/
 189 /** \name GL Visual allocation/destruction                            */
 190 /**********************************************************************/
 191 /*@{*/
 192
 193 /**
 194  * Allocates a struct gl_config structure and initializes it via
 195  * _mesa_initialize_visual().
 196  *
 197  * \param dbFlag double buffering
 198  * \param stereoFlag stereo buffer
 199  * \param depthBits requested bits per depth buffer value. Any value in [0, 32]
 200  * is acceptable but the actual depth type will be GLushort or GLuint as
 201  * needed.
 202  * \param stencilBits requested minimum bits per stencil buffer value
 203  * \param accumRedBits, accumGreenBits, accumBlueBits, accumAlphaBits number
 204  * of bits per color component in accum buffer.
 205  * \param indexBits number of bits per pixel if \p rgbFlag is GL_FALSE
 206  * \param redBits number of bits per color component in frame buffer for RGB(A)
 207  * mode.  We always use 8 in core Mesa though.
 208  * \param greenBits same as above.
 209  * \param blueBits same as above.
 210  * \param alphaBits same as above.
 211  * \param numSamples not really used.
 212  *
 213  * \return pointer to new struct gl_config or NULL if requested parameters
 214  * can't be met.
 215  *
 216  * \note Need to add params for level and numAuxBuffers (at least)
 217  */
 218 struct gl_config *
 219 _mesa_create_visual( GLboolean dbFlag,
 220                      GLboolean stereoFlag,
 221                      GLint redBits,
 222                      GLint greenBits,
 223                      GLint blueBits,
 224                      GLint alphaBits,
 225                      GLint depthBits,
 226                      GLint stencilBits,
 227                      GLint accumRedBits,
 228                      GLint accumGreenBits,
 229                      GLint accumBlueBits,
 230                      GLint accumAlphaBits,
 231                      GLuint numSamples )
 232 {
 233    struct gl_config *vis = CALLOC_STRUCT(gl_config);
 234    if (vis) {
 235       if (!_mesa_initialize_visual(vis, dbFlag, stereoFlag,
 236                                    redBits, greenBits, blueBits, alphaBits,
 237                                    depthBits, stencilBits,
 238                                    accumRedBits, accumGreenBits,
 239                                    accumBlueBits, accumAlphaBits,
 240                                    numSamples)) {
 241          free(vis);
 242          return NULL;
 243       }
 244    }
 245    return vis;
 246 }
 247
 248
 249 /**
 250  * Makes some sanity checks and fills in the fields of the struct
 251  * gl_config object with the given parameters.  If the caller needs to
 252  * set additional fields, he should just probably init the whole
 253  * gl_config object himself.
 254  *
 255  * \return GL_TRUE on success, or GL_FALSE on failure.
 256  *
 257  * \sa _mesa_create_visual() above for the parameter description.
 258  */
 259 GLboolean
 260 _mesa_initialize_visual( struct gl_config *vis,
 261                          GLboolean dbFlag,
 262                          GLboolean stereoFlag,
 263                          GLint redBits,
 264                          GLint greenBits,
 265                          GLint blueBits,
 266                          GLint alphaBits,
 267                          GLint depthBits,
 268                          GLint stencilBits,
 269                          GLint accumRedBits,
 270                          GLint accumGreenBits,
 271                          GLint accumBlueBits,
 272                          GLint accumAlphaBits,
 273                          GLuint numSamples )
 274 {
 275    assert(vis);
 276
 277    if (depthBits < 0 || depthBits > 32) {
 278       return GL_FALSE;
 279    }
 280    if (stencilBits < 0 || stencilBits > 8) {
 281       return GL_FALSE;
 282    }
 283    assert(accumRedBits >= 0);
 284    assert(accumGreenBits >= 0);
 285    assert(accumBlueBits >= 0);
 286    assert(accumAlphaBits >= 0);
 287
 288    vis->rgbMode          = GL_TRUE;
 289    vis->doubleBufferMode = dbFlag;
 290    vis->stereoMode       = stereoFlag;
 291
 292    vis->redBits          = redBits;
 293    vis->greenBits        = greenBits;
 294    vis->blueBits         = blueBits;
 295    vis->alphaBits        = alphaBits;
 296    vis->rgbBits          = redBits + greenBits + blueBits;
 297
 298    vis->indexBits      = 0;
 299    vis->depthBits      = depthBits;
 300    vis->stencilBits    = stencilBits;
 301
 302    vis->accumRedBits   = accumRedBits;
 303    vis->accumGreenBits = accumGreenBits;
 304    vis->accumBlueBits  = accumBlueBits;
 305    vis->accumAlphaBits = accumAlphaBits;
 306
 307    vis->haveAccumBuffer   = accumRedBits > 0;
 308    vis->haveDepthBuffer   = depthBits > 0;
 309    vis->haveStencilBuffer = stencilBits > 0;
 310
 311    vis->numAuxBuffers = 0;
 312    vis->level = 0;
 313    vis->sampleBuffers = numSamples > 0 ? 1 : 0;
 314    vis->samples = numSamples;
 315
 316    return GL_TRUE;
 317 }
 318
 319
 320 /**
 321  * Destroy a visual and free its memory.
 322  *
 323  * \param vis visual.
 324  *
 325  * Frees the visual structure.
 326  */
 327 void
 328 _mesa_destroy_visual( struct gl_config *vis )
 329 {
 330    free(vis);
 331 }
 332
 333 /*@}*/
 334
 335
 336 /**********************************************************************/
 337 /** \name Context allocation, initialization, destroying
 338  *
 339  * The purpose of the most initialization functions here is to provide the
 340  * default state values according to the OpenGL specification.
 341  */
 342 /**********************************************************************/
 343 /*@{*/
 344
 345
 346 /**
 347  * One-time initialization mutex lock.
 348  *
 349  * \sa Used by one_time_init().
 350  */
 351 mtx_t OneTimeLock = _MTX_INITIALIZER_NP;
 352
 353
 354 /**
 355  * Calls all the various one-time-fini functions in Mesa
 356  */
 357
 358 static void
 359 one_time_fini(void)
 360 {
 361    _mesa_destroy_shader_compiler();
 362    _mesa_locale_fini();
 363 }
 364
 365 /**
 366  * Calls all the various one-time-init functions in Mesa.
 367  *
 368  * While holding a global mutex lock, calls several initialization functions,
 369  * and sets the glapi callbacks if the \c MESA_DEBUG environment variable is
 370  * defined.
 371  *
 372  * \sa _math_init().
 373  */
 374 static void
 375 one_time_init( struct gl_context *ctx )
 376 {
 377    static GLbitfield api_init_mask = 0x0;
 378
 379    mtx_lock(&OneTimeLock);
 380
 381    /* truly one-time init */
 382    if (!api_init_mask) {
 383       GLuint i;
 384
 385       STATIC_ASSERT(sizeof(GLbyte) == 1);
 386       STATIC_ASSERT(sizeof(GLubyte) == 1);
 387       STATIC_ASSERT(sizeof(GLshort) == 2);
 388       STATIC_ASSERT(sizeof(GLushort) == 2);
 389       STATIC_ASSERT(sizeof(GLint) == 4);
 390       STATIC_ASSERT(sizeof(GLuint) == 4);
 391
 392       _mesa_locale_init();
 393
 394       _mesa_one_time_init_extension_overrides(ctx);
 395
 396       _mesa_get_cpu_features();
 397
 398       for (i = 0; i < 256; i++) {
 399          _mesa_ubyte_to_float_color_tab[i] = (float) i / 255.0F;
 400       }
 401
 402       atexit(one_time_fini);
 403
 404 #if defined(DEBUG)
 405       if (MESA_VERBOSE != 0) {
 406          _mesa_debug(ctx, "Mesa " PACKAGE_VERSION " DEBUG build"
 407 #ifdef MESA_GIT_SHA1
 408                      " (" MESA_GIT_SHA1 ")"
 409 #endif
 410                      "\n");
 411       }
 412 #endif
 413    }
 414
 415    /* per-API one-time init */
 416    if (!(api_init_mask & (1 << ctx->API))) {
 417       _mesa_init_remap_table();
 418    }
 419
 420    api_init_mask |= 1 << ctx->API;
 421
 422    mtx_unlock(&OneTimeLock);
 423 }
 424
 425
 426 /**
 427  * Initialize fields of gl_current_attrib (aka ctx->Current.*)
 428  */
 429 static void
 430 _mesa_init_current(struct gl_context *ctx)
 431 {
 432    GLuint i;
 433
 434    /* Init all to (0,0,0,1) */
 435    for (i = 0; i < ARRAY_SIZE(ctx->Current.Attrib); i++) {
 436       ASSIGN_4V( ctx->Current.Attrib[i], 0.0, 0.0, 0.0, 1.0 );
 437    }
 438
 439    /* redo special cases: */
 440    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_NORMAL], 0.0, 0.0, 1.0, 1.0 );
 441    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR0], 1.0, 1.0, 1.0, 1.0 );
 442    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR1], 0.0, 0.0, 0.0, 1.0 );
 443    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR_INDEX], 1.0, 0.0, 0.0, 1.0 );
 444    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_EDGEFLAG], 1.0, 0.0, 0.0, 1.0 );
 445 }
 446
 447
 448 /**
 449  * Init vertex/fragment/geometry program limits.
 450  * Important: drivers should override these with actual limits.
 451  */
 452 static void
 453 init_program_limits(struct gl_constants *consts, gl_shader_stage stage,
 454                     struct gl_program_constants *prog)
 455 {
 456    prog->MaxInstructions = MAX_PROGRAM_INSTRUCTIONS;
 457    prog->MaxAluInstructions = MAX_PROGRAM_INSTRUCTIONS;
 458    prog->MaxTexInstructions = MAX_PROGRAM_INSTRUCTIONS;
 459    prog->MaxTexIndirections = MAX_PROGRAM_INSTRUCTIONS;
 460    prog->MaxTemps = MAX_PROGRAM_TEMPS;
 461    prog->MaxEnvParams = MAX_PROGRAM_ENV_PARAMS;
 462    prog->MaxLocalParams = MAX_PROGRAM_LOCAL_PARAMS;
 463    prog->MaxAddressOffset = MAX_PROGRAM_LOCAL_PARAMS;
 464
 465    switch (stage) {
 466    case MESA_SHADER_VERTEX:
 467       prog->MaxParameters = MAX_VERTEX_PROGRAM_PARAMS;
 468       prog->MaxAttribs = MAX_VERTEX_GENERIC_ATTRIBS;
 469       prog->MaxAddressRegs = MAX_VERTEX_PROGRAM_ADDRESS_REGS;
 470       prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 471       prog->MaxInputComponents = 0; /* value not used */
 472       prog->MaxOutputComponents = 16 * 4; /* old limit not to break tnl and swrast */
 473       break;
 474    case MESA_SHADER_FRAGMENT:
 475       prog->MaxParameters = MAX_FRAGMENT_PROGRAM_PARAMS;
 476       prog->MaxAttribs = MAX_FRAGMENT_PROGRAM_INPUTS;
 477       prog->MaxAddressRegs = MAX_FRAGMENT_PROGRAM_ADDRESS_REGS;
 478       prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 479       prog->MaxInputComponents = 16 * 4; /* old limit not to break tnl and swrast */
 480       prog->MaxOutputComponents = 0; /* value not used */
 481       break;
 482    case MESA_SHADER_TESS_CTRL:
 483    case MESA_SHADER_TESS_EVAL:
 484    case MESA_SHADER_GEOMETRY:
 485       prog->MaxParameters = MAX_VERTEX_PROGRAM_PARAMS;
 486       prog->MaxAttribs = MAX_VERTEX_GENERIC_ATTRIBS;
 487       prog->MaxAddressRegs = MAX_VERTEX_PROGRAM_ADDRESS_REGS;
 488       prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 489       prog->MaxInputComponents = 16 * 4; /* old limit not to break tnl and swrast */
 490       prog->MaxOutputComponents = 16 * 4; /* old limit not to break tnl and swrast */
 491       break;
 492    case MESA_SHADER_COMPUTE:
 493       prog->MaxParameters = 0; /* not meaningful for compute shaders */
 494       prog->MaxAttribs = 0; /* not meaningful for compute shaders */
 495       prog->MaxAddressRegs = 0; /* not meaningful for compute shaders */
 496       prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 497       prog->MaxInputComponents = 0; /* not meaningful for compute shaders */
 498       prog->MaxOutputComponents = 0; /* not meaningful for compute shaders */
 499       break;
 500    default:
 501       assert(0 && "Bad shader stage in init_program_limits()");
 502    }
 503
 504    /* Set the native limits to zero.  This implies that there is no native
 505     * support for shaders.  Let the drivers fill in the actual values.
 506     */
 507    prog->MaxNativeInstructions = 0;
 508    prog->MaxNativeAluInstructions = 0;
 509    prog->MaxNativeTexInstructions = 0;
 510    prog->MaxNativeTexIndirections = 0;
 511    prog->MaxNativeAttribs = 0;
 512    prog->MaxNativeTemps = 0;
 513    prog->MaxNativeAddressRegs = 0;
 514    prog->MaxNativeParameters = 0;
 515
 516    /* Set GLSL datatype range/precision info assuming IEEE float values.
 517     * Drivers should override these defaults as needed.
 518     */
 519    prog->MediumFloat.RangeMin = 127;
 520    prog->MediumFloat.RangeMax = 127;
 521    prog->MediumFloat.Precision = 23;
 522    prog->LowFloat = prog->HighFloat = prog->MediumFloat;
 523
 524    /* Assume ints are stored as floats for now, since this is the least-common
 525     * denominator.  The OpenGL ES spec implies (page 132) that the precision
 526     * of integer types should be 0.  Practically speaking, IEEE
 527     * single-precision floating point values can only store integers in the
 528     * range [-0x01000000, 0x01000000] without loss of precision.
 529     */
 530    prog->MediumInt.RangeMin = 24;
 531    prog->MediumInt.RangeMax = 24;
 532    prog->MediumInt.Precision = 0;
 533    prog->LowInt = prog->HighInt = prog->MediumInt;
 534
 535    prog->MaxUniformBlocks = 12;
 536    prog->MaxCombinedUniformComponents = (prog->MaxUniformComponents +
 537                                          consts->MaxUniformBlockSize / 4 *
 538                                          prog->MaxUniformBlocks);
 539
 540    prog->MaxAtomicBuffers = 0;
 541    prog->MaxAtomicCounters = 0;
 542
 543    prog->MaxShaderStorageBlocks = 8;
 544 }
 545
 546
 547 /**
 548  * Initialize fields of gl_constants (aka ctx->Const.*).
 549  * Use defaults from config.h.  The device drivers will often override
 550  * some of these values (such as number of texture units).
 551  */
 552 void
 553 _mesa_init_constants(struct gl_constants *consts, gl_api api)
 554 {
 555    int i;
 556    assert(consts);
 557
 558    /* Constants, may be overriden (usually only reduced) by device drivers */
 559    consts->MaxTextureMbytes = MAX_TEXTURE_MBYTES;
 560    consts->MaxTextureLevels = MAX_TEXTURE_LEVELS;
 561    consts->Max3DTextureLevels = MAX_3D_TEXTURE_LEVELS;
 562    consts->MaxCubeTextureLevels = MAX_CUBE_TEXTURE_LEVELS;
 563    consts->MaxTextureRectSize = MAX_TEXTURE_RECT_SIZE;
 564    consts->MaxArrayTextureLayers = MAX_ARRAY_TEXTURE_LAYERS;
 565    consts->MaxTextureCoordUnits = MAX_TEXTURE_COORD_UNITS;
 566    consts->Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 567    consts->MaxTextureUnits = MIN2(consts->MaxTextureCoordUnits,
 568                                      consts->Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits);
 569    consts->MaxTextureMaxAnisotropy = MAX_TEXTURE_MAX_ANISOTROPY;
 570    consts->MaxTextureLodBias = MAX_TEXTURE_LOD_BIAS;
 571    consts->MaxTextureBufferSize = 65536;
 572    consts->TextureBufferOffsetAlignment = 1;
 573    consts->MaxArrayLockSize = MAX_ARRAY_LOCK_SIZE;
 574    consts->SubPixelBits = SUB_PIXEL_BITS;
 575    consts->MinPointSize = MIN_POINT_SIZE;
 576    consts->MaxPointSize = MAX_POINT_SIZE;
 577    consts->MinPointSizeAA = MIN_POINT_SIZE;
 578    consts->MaxPointSizeAA = MAX_POINT_SIZE;
 579    consts->PointSizeGranularity = (GLfloat) POINT_SIZE_GRANULARITY;
 580    consts->MinLineWidth = MIN_LINE_WIDTH;
 581    consts->MaxLineWidth = MAX_LINE_WIDTH;
 582    consts->MinLineWidthAA = MIN_LINE_WIDTH;
 583    consts->MaxLineWidthAA = MAX_LINE_WIDTH;
 584    consts->LineWidthGranularity = (GLfloat) LINE_WIDTH_GRANULARITY;
 585    consts->MaxClipPlanes = 6;
 586    consts->MaxLights = MAX_LIGHTS;
 587    consts->MaxShininess = 128.0;
 588    consts->MaxSpotExponent = 128.0;
 589    consts->MaxViewportWidth = 16384;
 590    consts->MaxViewportHeight = 16384;
 591    consts->MinMapBufferAlignment = 64;
 592
 593    /* Driver must override these values if ARB_viewport_array is supported. */
 594    consts->MaxViewports = 1;
 595    consts->ViewportSubpixelBits = 0;
 596    consts->ViewportBounds.Min = 0;
 597    consts->ViewportBounds.Max = 0;
 598
 599    /** GL_ARB_uniform_buffer_object */
 600    consts->MaxCombinedUniformBlocks = 36;
 601    consts->MaxUniformBufferBindings = 36;
 602    consts->MaxUniformBlockSize = 16384;
 603    consts->UniformBufferOffsetAlignment = 1;
 604
 605    /** GL_ARB_shader_storage_buffer_object */
 606    consts->MaxCombinedShaderStorageBlocks = 8;
 607    consts->MaxShaderStorageBufferBindings = 8;
 608    consts->MaxShaderStorageBlockSize = 128 * 1024 * 1024; /* 2^27 */
 609    consts->ShaderStorageBufferOffsetAlignment = 256;
 610
 611    /* GL_ARB_explicit_uniform_location, GL_MAX_UNIFORM_LOCATIONS */
 612    consts->MaxUserAssignableUniformLocations =
 613       4 * MESA_SHADER_STAGES * MAX_UNIFORMS;
 614
 615    for (i = 0; i < MESA_SHADER_STAGES; i++)
 616       init_program_limits(consts, i, &consts->Program[i]);
 617
 618    consts->MaxProgramMatrices = MAX_PROGRAM_MATRICES;
 619    consts->MaxProgramMatrixStackDepth = MAX_PROGRAM_MATRIX_STACK_DEPTH;
 620
 621    /* Assume that if GLSL 1.30+ (or GLSL ES 3.00+) is supported that
 622     * gl_VertexID is implemented using a native hardware register with OpenGL
 623     * semantics.
 624     */
 625    consts->VertexID_is_zero_based = false;
 626
 627    /* GL_ARB_draw_buffers */
 628    consts->MaxDrawBuffers = MAX_DRAW_BUFFERS;
 629
 630    consts->MaxColorAttachments = MAX_COLOR_ATTACHMENTS;
 631    consts->MaxRenderbufferSize = MAX_RENDERBUFFER_SIZE;
 632
 633    consts->Program[MESA_SHADER_VERTEX].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 634    consts->MaxCombinedTextureImageUnits = MAX_COMBINED_TEXTURE_IMAGE_UNITS;
 635    consts->MaxVarying = 16; /* old limit not to break tnl and swrast */
 636    consts->Program[MESA_SHADER_GEOMETRY].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 637    consts->MaxGeometryOutputVertices = MAX_GEOMETRY_OUTPUT_VERTICES;
 638    consts->MaxGeometryTotalOutputComponents = MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS;
 639
 640    /* Shading language version */
 641    consts->GLSLVersion = 120;
 642    _mesa_override_glsl_version(consts);
 643
 644 #ifdef DEBUG
 645    consts->GenerateTemporaryNames = true;
 646 #else
 647    consts->GenerateTemporaryNames = false;
 648 #endif
 649
 650    /* GL_ARB_framebuffer_object */
 651    consts->MaxSamples = 0;
 652
 653    /* GLSL default if NativeIntegers == FALSE */
 654    consts->UniformBooleanTrue = FLOAT_AS_UNION(1.0f).u;
 655
 656    /* GL_ARB_sync */
 657    consts->MaxServerWaitTimeout = 0x7fffffff7fffffffULL;
 658
 659    /* GL_EXT_provoking_vertex */
 660    consts->QuadsFollowProvokingVertexConvention = GL_TRUE;
 661
 662    /** GL_ARB_viewport_array */
 663    consts->LayerAndVPIndexProvokingVertex = GL_UNDEFINED_VERTEX;
 664
 665    /* GL_EXT_transform_feedback */
 666    consts->MaxTransformFeedbackBuffers = MAX_FEEDBACK_BUFFERS;
 667    consts->MaxTransformFeedbackSeparateComponents = 4 * MAX_FEEDBACK_ATTRIBS;
 668    consts->MaxTransformFeedbackInterleavedComponents = 4 * MAX_FEEDBACK_ATTRIBS;
 669    consts->MaxVertexStreams = 1;
 670
 671    /* GL 3.2  */
 672    consts->ProfileMask = api == API_OPENGL_CORE
 673                           ? GL_CONTEXT_CORE_PROFILE_BIT
 674                           : GL_CONTEXT_COMPATIBILITY_PROFILE_BIT;
 675
 676    /* GL 4.4 */
 677    consts->MaxVertexAttribStride = 2048;
 678
 679    /** GL_EXT_gpu_shader4 */
 680    consts->MinProgramTexelOffset = -8;
 681    consts->MaxProgramTexelOffset = 7;
 682
 683    /* GL_ARB_texture_gather */
 684    consts->MinProgramTextureGatherOffset = -8;
 685    consts->MaxProgramTextureGatherOffset = 7;
 686
 687    /* GL_ARB_robustness */
 688    consts->ResetStrategy = GL_NO_RESET_NOTIFICATION_ARB;
 689
 690    /* GL_KHR_robustness */
 691    consts->RobustAccess = GL_FALSE;
 692
 693    /* ES 3.0 or ARB_ES3_compatibility */
 694    consts->MaxElementIndex = 0xffffffffu;
 695
 696    /* GL_ARB_texture_multisample */
 697    consts->MaxColorTextureSamples = 1;
 698    consts->MaxDepthTextureSamples = 1;
 699    consts->MaxIntegerSamples = 1;
 700
 701    /* GL_ARB_shader_atomic_counters */
 702    consts->MaxAtomicBufferBindings = MAX_COMBINED_ATOMIC_BUFFERS;
 703    consts->MaxAtomicBufferSize = MAX_ATOMIC_COUNTERS * ATOMIC_COUNTER_SIZE;
 704    consts->MaxCombinedAtomicBuffers = MAX_COMBINED_ATOMIC_BUFFERS;
 705    consts->MaxCombinedAtomicCounters = MAX_ATOMIC_COUNTERS;
 706
 707    /* GL_ARB_vertex_attrib_binding */
 708    consts->MaxVertexAttribRelativeOffset = 2047;
 709    consts->MaxVertexAttribBindings = MAX_VERTEX_GENERIC_ATTRIBS;
 710
 711    /* GL_ARB_compute_shader */
 712    consts->MaxComputeWorkGroupCount[0] = 65535;
 713    consts->MaxComputeWorkGroupCount[1] = 65535;
 714    consts->MaxComputeWorkGroupCount[2] = 65535;
 715    consts->MaxComputeWorkGroupSize[0] = 1024;
 716    consts->MaxComputeWorkGroupSize[1] = 1024;
 717    consts->MaxComputeWorkGroupSize[2] = 64;
 718    /* Enables compute support for GLES 3.1 if >= 128 */
 719    consts->MaxComputeWorkGroupInvocations = 0;
 720
 721    /** GL_ARB_gpu_shader5 */
 722    consts->MinFragmentInterpolationOffset = MIN_FRAGMENT_INTERPOLATION_OFFSET;
 723    consts->MaxFragmentInterpolationOffset = MAX_FRAGMENT_INTERPOLATION_OFFSET;
 724
 725    /** GL_KHR_context_flush_control */
 726    consts->ContextReleaseBehavior = GL_CONTEXT_RELEASE_BEHAVIOR_FLUSH;
 727
 728    /** GL_ARB_tessellation_shader */
 729    consts->MaxTessGenLevel = MAX_TESS_GEN_LEVEL;
 730    consts->MaxPatchVertices = MAX_PATCH_VERTICES;
 731    consts->Program[MESA_SHADER_TESS_CTRL].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 732    consts->Program[MESA_SHADER_TESS_EVAL].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 733    consts->MaxTessPatchComponents = MAX_TESS_PATCH_COMPONENTS;
 734    consts->MaxTessControlTotalOutputComponents = MAX_TESS_CONTROL_TOTAL_OUTPUT_COMPONENTS;
 735    consts->PrimitiveRestartForPatches = false;
 736
 737    /** GL_ARB_compute_variable_group_size */
 738    consts->MaxComputeVariableGroupSize[0] = 512;
 739    consts->MaxComputeVariableGroupSize[1] = 512;
 740    consts->MaxComputeVariableGroupSize[2] = 64;
 741    consts->MaxComputeVariableGroupInvocations = 512;
 742 }
 743
 744
 745 /**
 746  * Do some sanity checks on the limits/constants for the given context.
 747  * Only called the first time a context is bound.
 748  */
 749 static void
 750 check_context_limits(struct gl_context *ctx)
 751 {
 752    (void) ctx;
 753
 754    /* check that we don't exceed the size of various bitfields */
 755    assert(VARYING_SLOT_MAX <=
 756           (8 * sizeof(ctx->VertexProgram._Current->info.outputs_written)));
 757    assert(VARYING_SLOT_MAX <=
 758           (8 * sizeof(ctx->FragmentProgram._Current->info.inputs_read)));
 759
 760    /* shader-related checks */
 761    assert(ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 762    assert(ctx->Const.Program[MESA_SHADER_VERTEX].MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 763
 764    /* Texture unit checks */
 765    assert(ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits > 0);
 766    assert(ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
 767    assert(ctx->Const.MaxTextureCoordUnits > 0);
 768    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
 769    assert(ctx->Const.MaxTextureUnits > 0);
 770    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
 771    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
 772    assert(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits,
 773                                              ctx->Const.MaxTextureCoordUnits));
 774    assert(ctx->Const.MaxCombinedTextureImageUnits > 0);
 775    assert(ctx->Const.MaxCombinedTextureImageUnits <= MAX_COMBINED_TEXTURE_IMAGE_UNITS);
 776    assert(ctx->Const.MaxTextureCoordUnits <= MAX_COMBINED_TEXTURE_IMAGE_UNITS);
 777    /* number of coord units cannot be greater than number of image units */
 778    assert(ctx->Const.MaxTextureCoordUnits <= ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits);
 779
 780
 781    /* Texture size checks */
 782    assert(ctx->Const.MaxTextureLevels <= MAX_TEXTURE_LEVELS);
 783    assert(ctx->Const.Max3DTextureLevels <= MAX_3D_TEXTURE_LEVELS);
 784    assert(ctx->Const.MaxCubeTextureLevels <= MAX_CUBE_TEXTURE_LEVELS);
 785    assert(ctx->Const.MaxTextureRectSize <= MAX_TEXTURE_RECT_SIZE);
 786
 787    /* Texture level checks */
 788    assert(MAX_TEXTURE_LEVELS >= MAX_3D_TEXTURE_LEVELS);
 789    assert(MAX_TEXTURE_LEVELS >= MAX_CUBE_TEXTURE_LEVELS);
 790
 791    /* Max texture size should be <= max viewport size (render to texture) */
 792    assert((1U << (ctx->Const.MaxTextureLevels - 1))
 793           <= ctx->Const.MaxViewportWidth);
 794    assert((1U << (ctx->Const.MaxTextureLevels - 1))
 795           <= ctx->Const.MaxViewportHeight);
 796
 797    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
 798
 799    /* if this fails, add more enum values to gl_buffer_index */
 800    assert(BUFFER_COLOR0 + MAX_DRAW_BUFFERS <= BUFFER_COUNT);
 801
 802    /* XXX probably add more tests */
 803 }
 804
 805
 806 /**
 807  * Initialize the attribute groups in a GL context.
 808  *
 809  * \param ctx GL context.
 810  *
 811  * Initializes all the attributes, calling the respective <tt>init*</tt>
 812  * functions for the more complex data structures.
 813  */
 814 static GLboolean
 815 init_attrib_groups(struct gl_context *ctx)
 816 {
 817    assert(ctx);
 818
 819    /* Constants */
 820    _mesa_init_constants(&ctx->Const, ctx->API);
 821
 822    /* Extensions */
 823    _mesa_init_extensions(&ctx->Extensions);
 824
 825    /* Attribute Groups */
 826    _mesa_init_accum( ctx );
 827    _mesa_init_attrib( ctx );
 828    _mesa_init_bbox( ctx );
 829    _mesa_init_buffer_objects( ctx );
 830    _mesa_init_color( ctx );
 831    _mesa_init_current( ctx );
 832    _mesa_init_depth( ctx );
 833    _mesa_init_debug( ctx );
 834    _mesa_init_debug_output( ctx );
 835    _mesa_init_display_list( ctx );
 836    _mesa_init_eval( ctx );
 837    _mesa_init_fbobjects( ctx );
 838    _mesa_init_feedback( ctx );
 839    _mesa_init_fog( ctx );
 840    _mesa_init_hint( ctx );
 841    _mesa_init_image_units( ctx );
 842    _mesa_init_line( ctx );
 843    _mesa_init_lighting( ctx );
 844    _mesa_init_matrix( ctx );
 845    _mesa_init_multisample( ctx );
 846    _mesa_init_performance_monitors( ctx );
 847    _mesa_init_performance_queries( ctx );
 848    _mesa_init_pipeline( ctx );
 849    _mesa_init_pixel( ctx );
 850    _mesa_init_pixelstore( ctx );
 851    _mesa_init_point( ctx );
 852    _mesa_init_polygon( ctx );
 853    _mesa_init_program( ctx );
 854    _mesa_init_queryobj( ctx );
 855    _mesa_init_sync( ctx );
 856    _mesa_init_rastpos( ctx );
 857    _mesa_init_scissor( ctx );
 858    _mesa_init_shader_state( ctx );
 859    _mesa_init_stencil( ctx );
 860    _mesa_init_transform( ctx );
 861    _mesa_init_transform_feedback( ctx );
 862    _mesa_init_varray( ctx );
 863    _mesa_init_viewport( ctx );
 864    _mesa_init_resident_handles( ctx );
 865
 866    if (!_mesa_init_texture( ctx ))
 867       return GL_FALSE;
 868
 869    /* Miscellaneous */
 870    ctx->TileRasterOrderIncreasingX = GL_TRUE;
 871    ctx->TileRasterOrderIncreasingY = GL_TRUE;
 872    ctx->NewState = _NEW_ALL;
 873    ctx->NewDriverState = ~0;
 874    ctx->ErrorValue = GL_NO_ERROR;
 875    ctx->ShareGroupReset = false;
 876    ctx->varying_vp_inputs = VERT_BIT_ALL;
 877
 878    return GL_TRUE;
 879 }
 880
 881
 882 /**
 883  * Update default objects in a GL context with respect to shared state.
 884  *
 885  * \param ctx GL context.
 886  *
 887  * Removes references to old default objects, (texture objects, program
 888  * objects, etc.) and changes to reference those from the current shared
 889  * state.
 890  */
 891 static GLboolean
 892 update_default_objects(struct gl_context *ctx)
 893 {
 894    assert(ctx);
 895
 896    _mesa_update_default_objects_program(ctx);
 897    _mesa_update_default_objects_texture(ctx);
 898    _mesa_update_default_objects_buffer_objects(ctx);
 899
 900    return GL_TRUE;
 901 }
 902
 903
 904 /* XXX this is temporary and should be removed at some point in the
 905  * future when there's a reasonable expectation that the libGL library
 906  * contains the _glapi_new_nop_table() and _glapi_set_nop_handler()
 907  * functions which were added in Mesa 10.6.
 908  */
 909 #if !defined(_WIN32)
 910 /* Avoid libGL / driver ABI break */
 911 #define USE_GLAPI_NOP_FEATURES 0
 912 #else
 913 #define USE_GLAPI_NOP_FEATURES 1
 914 #endif
 915
 916
 917 /**
 918  * This function is called by the glapi no-op functions.  For each OpenGL
 919  * function/entrypoint there's a simple no-op function.  These "no-op"
 920  * functions call this function.
 921  *
 922  * If there's a current OpenGL context for the calling thread, we record a
 923  * GL_INVALID_OPERATION error.  This can happen either because the app's
 924  * calling an unsupported extension function, or calling an illegal function
 925  * (such as glClear between glBegin/glEnd).
 926  *
 927  * If there's no current OpenGL context for the calling thread, we can
 928  * print a message to stderr.
 929  *
 930  * \param name  the name of the OpenGL function
 931  */
 932 #if USE_GLAPI_NOP_FEATURES
 933 static void
 934 nop_handler(const char *name)
 935 {
 936    GET_CURRENT_CONTEXT(ctx);
 937    if (ctx) {
 938       _mesa_error(ctx, GL_INVALID_OPERATION, "%s(invalid call)", name);
 939    }
 940 #if defined(DEBUG)
 941    else if (getenv("MESA_DEBUG") || getenv("LIBGL_DEBUG")) {
 942       fprintf(stderr,
 943               "GL User Error: gl%s called without a rendering context\n",
 944               name);
 945       fflush(stderr);
 946    }
 947 #endif
 948 }
 949 #endif
 950
 951
 952 /**
 953  * Special no-op glFlush, see below.
 954  */
 955 #if defined(_WIN32)
 956 static void GLAPIENTRY
 957 nop_glFlush(void)
 958 {
 959    /* don't record an error like we do in nop_handler() */
 960 }
 961 #endif
 962
 963
 964 #if !USE_GLAPI_NOP_FEATURES
 965 static int
 966 generic_nop(void)
 967 {
 968    GET_CURRENT_CONTEXT(ctx);
 969    _mesa_error(ctx, GL_INVALID_OPERATION,
 970                "unsupported function called "
 971                "(unsupported extension or deprecated function?)");
 972    return 0;
 973 }
 974 #endif
 975
 976
 977 /**
 978  * Create a new API dispatch table in which all entries point to the
 979  * generic_nop() function.  This will not work on Windows because of
 980  * the __stdcall convention which requires the callee to clean up the
 981  * call stack.  That's impossible with one generic no-op function.
 982  */
 983 struct _glapi_table *
 984 _mesa_new_nop_table(unsigned numEntries)
 985 {
 986    struct _glapi_table *table;
 987
 988 #if !USE_GLAPI_NOP_FEATURES
 989    table = malloc(numEntries * sizeof(_glapi_proc));
 990    if (table) {
 991       _glapi_proc *entry = (_glapi_proc *) table;
 992       unsigned i;
 993       for (i = 0; i < numEntries; i++) {
 994          entry[i] = (_glapi_proc) generic_nop;
 995       }
 996    }
 997 #else
 998    table = _glapi_new_nop_table(numEntries);
 999 #endif
1000    return table;
1001 }
1002
1003
1004 /**
1005  * Allocate and initialize a new dispatch table.  The table will be
1006  * populated with pointers to "no-op" functions.  In turn, the no-op
1007  * functions will call nop_handler() above.
1008  */
1009 struct _glapi_table *
1010 _mesa_alloc_dispatch_table(void)
1011 {
1012    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
1013     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
1014     * Mesa we do this to accommodate different versions of libGL and various
1015     * DRI drivers.
1016     */
1017    int numEntries = MAX2(_glapi_get_dispatch_table_size(), _gloffset_COUNT);
1018
1019    struct _glapi_table *table = _mesa_new_nop_table(numEntries);
1020
1021 #if defined(_WIN32)
1022    if (table) {
1023       /* This is a special case for Windows in the event that
1024        * wglGetProcAddress is called between glBegin/End().
1025        *
1026        * The MS opengl32.dll library apparently calls glFlush from
1027        * wglGetProcAddress().  If we're inside glBegin/End(), glFlush
1028        * will dispatch to _mesa_generic_nop() and we'll generate a
1029        * GL_INVALID_OPERATION error.
1030        *
1031        * The specific case which hits this is piglit's primitive-restart
1032        * test which calls glPrimitiveRestartNV() inside glBegin/End.  The
1033        * first time we call glPrimitiveRestartNV() Piglit's API dispatch
1034        * code will try to resolve the function by calling wglGetProcAddress.
1035        * This raises GL_INVALID_OPERATION and an assert(glGetError()==0)
1036        * will fail causing the test to fail.  By suppressing the error, the
1037        * assertion passes and the test continues.
1038        */
1039       SET_Flush(table, nop_glFlush);
1040    }
1041 #endif
1042
1043 #if USE_GLAPI_NOP_FEATURES
1044    _glapi_set_nop_handler(nop_handler);
1045 #endif
1046
1047    return table;
1048 }
1049
1050 /**
1051  * Creates a minimal dispatch table for use within glBegin()/glEnd().
1052  *
1053  * This ensures that we generate GL_INVALID_OPERATION errors from most
1054  * functions, since the set of functions that are valid within Begin/End is
1055  * very small.
1056  *
1057  * From the GL 1.0 specification section 2.6.3, "GL Commands within
1058  * Begin/End"
1059  *
1060  *     "The only GL commands that are allowed within any Begin/End pairs are
1061  *      the commands for specifying vertex coordinates, vertex color, normal
1062  *      coordinates, and texture coordinates (Vertex, Color, Index, Normal,
1063  *      TexCoord), EvalCoord and EvalPoint commands (see section 5.1),
1064  *      commands for specifying lighting material parameters (Material
1065  *      commands see section 2.12.2), display list invocation commands
1066  *      (CallList and CallLists see section 5.4), and the EdgeFlag
1067  *      command. Executing Begin after Begin has already been executed but
1068  *      before an End is issued generates the INVALID OPERATION error, as does
1069  *      executing End without a previous corresponding Begin. Executing any
1070  *      other GL command within Begin/End results in the error INVALID
1071  *      OPERATION."
1072  *
1073  * The table entries for specifying vertex attributes are set up by
1074  * install_vtxfmt() and _mesa_loopback_init_api_table(), and End() and dlists
1075  * are set by install_vtxfmt() as well.
1076  */
1077 static struct _glapi_table *
1078 create_beginend_table(const struct gl_context *ctx)
1079 {
1080    struct _glapi_table *table;
1081
1082    table = _mesa_alloc_dispatch_table();
1083    if (!table)
1084       return NULL;
1085
1086    /* Fill in functions which return a value, since they should return some
1087     * specific value even if they emit a GL_INVALID_OPERATION error from them
1088     * being called within glBegin()/glEnd().
1089     */
1090 #define COPY_DISPATCH(func) SET_##func(table, GET_##func(ctx->Exec))
1091
1092    COPY_DISPATCH(GenLists);
1093    COPY_DISPATCH(IsProgram);
1094    COPY_DISPATCH(IsVertexArray);
1095    COPY_DISPATCH(IsBuffer);
1096    COPY_DISPATCH(IsEnabled);
1097    COPY_DISPATCH(IsEnabledi);
1098    COPY_DISPATCH(IsRenderbuffer);
1099    COPY_DISPATCH(IsFramebuffer);
1100    COPY_DISPATCH(CheckFramebufferStatus);
1101    COPY_DISPATCH(RenderMode);
1102    COPY_DISPATCH(GetString);
1103    COPY_DISPATCH(GetStringi);
1104    COPY_DISPATCH(GetPointerv);
1105    COPY_DISPATCH(IsQuery);
1106    COPY_DISPATCH(IsSampler);
1107    COPY_DISPATCH(IsSync);
1108    COPY_DISPATCH(IsTexture);
1109    COPY_DISPATCH(IsTransformFeedback);
1110    COPY_DISPATCH(DeleteQueries);
1111    COPY_DISPATCH(AreTexturesResident);
1112    COPY_DISPATCH(FenceSync);
1113    COPY_DISPATCH(ClientWaitSync);
1114    COPY_DISPATCH(MapBuffer);
1115    COPY_DISPATCH(UnmapBuffer);
1116    COPY_DISPATCH(MapBufferRange);
1117    COPY_DISPATCH(ObjectPurgeableAPPLE);
1118    COPY_DISPATCH(ObjectUnpurgeableAPPLE);
1119
1120    _mesa_loopback_init_api_table(ctx, table);
1121
1122    return table;
1123 }
1124
1125 void
1126 _mesa_initialize_dispatch_tables(struct gl_context *ctx)
1127 {
1128    /* Do the code-generated setup of the exec table in api_exec.c. */
1129    _mesa_initialize_exec_table(ctx);
1130
1131    if (ctx->Save)
1132       _mesa_initialize_save_table(ctx);
1133 }
1134
1135 /**
1136  * Initialize a struct gl_context struct (rendering context).
1137  *
1138  * This includes allocating all the other structs and arrays which hang off of
1139  * the context by pointers.
1140  * Note that the driver needs to pass in its dd_function_table here since
1141  * we need to at least call driverFunctions->NewTextureObject to create the
1142  * default texture objects.
1143  *
1144  * Called by _mesa_create_context().
1145  *
1146  * Performs the imports and exports callback tables initialization, and
1147  * miscellaneous one-time initializations. If no shared context is supplied one
1148  * is allocated, and increase its reference count.  Setups the GL API dispatch
1149  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
1150  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
1151  * for debug flags.
1152  *
1153  * \param ctx the context to initialize
1154  * \param api the GL API type to create the context for
1155  * \param visual describes the visual attributes for this context or NULL to
1156  *               create a configless context
1157  * \param share_list points to context to share textures, display lists,
1158  *        etc with, or NULL
1159  * \param driverFunctions table of device driver functions for this context
1160  *        to use
1161  */
1162 GLboolean
1163 _mesa_initialize_context(struct gl_context *ctx,
1164                          gl_api api,
1165                          const struct gl_config *visual,
1166                          struct gl_context *share_list,
1167                          const struct dd_function_table *driverFunctions)
1168 {
1169    struct gl_shared_state *shared;
1170    int i;
1171
1172    assert(driverFunctions->NewTextureObject);
1173    assert(driverFunctions->FreeTextureImageBuffer);
1174
1175    ctx->API = api;
1176    ctx->DrawBuffer = NULL;
1177    ctx->ReadBuffer = NULL;
1178    ctx->WinSysDrawBuffer = NULL;
1179    ctx->WinSysReadBuffer = NULL;
1180
1181    if (visual) {
1182       ctx->Visual = *visual;
1183       ctx->HasConfig = GL_TRUE;
1184    }
1185    else {
1186       memset(&ctx->Visual, 0, sizeof ctx->Visual);
1187       ctx->HasConfig = GL_FALSE;
1188    }
1189
1190    _mesa_override_gl_version(ctx);
1191
1192    /* misc one-time initializations */
1193    one_time_init(ctx);
1194
1195    /* Plug in driver functions and context pointer here.
1196     * This is important because when we call alloc_shared_state() below
1197     * we'll call ctx->Driver.NewTextureObject() to create the default
1198     * textures.
1199     */
1200    ctx->Driver = *driverFunctions;
1201
1202    if (share_list) {
1203       /* share state with another context */
1204       shared = share_list->Shared;
1205    }
1206    else {
1207       /* allocate new, unshared state */
1208       shared = _mesa_alloc_shared_state(ctx);
1209       if (!shared)
1210          return GL_FALSE;
1211    }
1212
1213    _mesa_reference_shared_state(ctx, &ctx->Shared, shared);
1214
1215    if (!init_attrib_groups( ctx ))
1216       goto fail;
1217
1218    /* KHR_no_error is likely to crash, overflow memory, etc if an application
1219     * has errors so don't enable it for setuid processes.
1220     */
1221    if (env_var_as_boolean("MESA_NO_ERROR", false)) {
1222 #if !defined(_WIN32)
1223       if (geteuid() == getuid())
1224 #endif
1225          ctx->Const.ContextFlags |= GL_CONTEXT_FLAG_NO_ERROR_BIT_KHR;
1226    }
1227
1228    /* setup the API dispatch tables with all nop functions */
1229    ctx->OutsideBeginEnd = _mesa_alloc_dispatch_table();
1230    if (!ctx->OutsideBeginEnd)
1231       goto fail;
1232    ctx->Exec = ctx->OutsideBeginEnd;
1233    ctx->CurrentClientDispatch = ctx->CurrentServerDispatch = ctx->OutsideBeginEnd;
1234
1235    ctx->FragmentProgram._MaintainTexEnvProgram
1236       = (getenv("MESA_TEX_PROG") != NULL);
1237
1238    ctx->VertexProgram._MaintainTnlProgram
1239       = (getenv("MESA_TNL_PROG") != NULL);
1240    if (ctx->VertexProgram._MaintainTnlProgram) {
1241       /* this is required... */
1242       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
1243    }
1244
1245    /* Mesa core handles all the formats that mesa core knows about.
1246     * Drivers will want to override this list with just the formats
1247     * they can handle, and confirm that appropriate fallbacks exist in
1248     * _mesa_choose_tex_format().
1249     */
1250    memset(&ctx->TextureFormatSupported, GL_TRUE,
1251           sizeof(ctx->TextureFormatSupported));
1252
1253    switch (ctx->API) {
1254    case API_OPENGL_COMPAT:
1255       ctx->BeginEnd = create_beginend_table(ctx);
1256       ctx->Save = _mesa_alloc_dispatch_table();
1257       if (!ctx->BeginEnd || !ctx->Save)
1258          goto fail;
1259
1260       /* fall-through */
1261    case API_OPENGL_CORE:
1262       break;
1263    case API_OPENGLES:
1264       /**
1265        * GL_OES_texture_cube_map says
1266        * "Initially all texture generation modes are set to REFLECTION_MAP_OES"
1267        */
1268       for (i = 0; i < ARRAY_SIZE(ctx->Texture.FixedFuncUnit); i++) {
1269          struct gl_fixedfunc_texture_unit *texUnit =
1270             &ctx->Texture.FixedFuncUnit[i];
1271
1272          texUnit->GenS.Mode = GL_REFLECTION_MAP_NV;
1273          texUnit->GenT.Mode = GL_REFLECTION_MAP_NV;
1274          texUnit->GenR.Mode = GL_REFLECTION_MAP_NV;
1275          texUnit->GenS._ModeBit = TEXGEN_REFLECTION_MAP_NV;
1276          texUnit->GenT._ModeBit = TEXGEN_REFLECTION_MAP_NV;
1277          texUnit->GenR._ModeBit = TEXGEN_REFLECTION_MAP_NV;
1278       }
1279       break;
1280    case API_OPENGLES2:
1281       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
1282       ctx->VertexProgram._MaintainTnlProgram = GL_TRUE;
1283       break;
1284    }
1285
1286    ctx->FirstTimeCurrent = GL_TRUE;
1287
1288    return GL_TRUE;
1289
1290 fail:
1291    _mesa_reference_shared_state(ctx, &ctx->Shared, NULL);
1292    free(ctx->BeginEnd);
1293    free(ctx->OutsideBeginEnd);
1294    free(ctx->Save);
1295    return GL_FALSE;
1296 }
1297
1298
1299 /**
1300  * Free the data associated with the given context.
1301  *
1302  * But doesn't free the struct gl_context struct itself.
1303  *
1304  * \sa _mesa_initialize_context() and init_attrib_groups().
1305  */
1306 void
1307 _mesa_free_context_data( struct gl_context *ctx )
1308 {
1309    if (!_mesa_get_current_context()){
1310       /* No current context, but we may need one in order to delete
1311        * texture objs, etc.  So temporarily bind the context now.
1312        */
1313       _mesa_make_current(ctx, NULL, NULL);
1314    }
1315
1316    /* unreference WinSysDraw/Read buffers */
1317    _mesa_reference_framebuffer(&ctx->WinSysDrawBuffer, NULL);
1318    _mesa_reference_framebuffer(&ctx->WinSysReadBuffer, NULL);
1319    _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
1320    _mesa_reference_framebuffer(&ctx->ReadBuffer, NULL);
1321
1322    _mesa_reference_program(ctx, &ctx->VertexProgram.Current, NULL);
1323    _mesa_reference_program(ctx, &ctx->VertexProgram._Current, NULL);
1324    _mesa_reference_program(ctx, &ctx->VertexProgram._TnlProgram, NULL);
1325
1326    _mesa_reference_program(ctx, &ctx->TessCtrlProgram._Current, NULL);
1327    _mesa_reference_program(ctx, &ctx->TessEvalProgram._Current, NULL);
1328    _mesa_reference_program(ctx, &ctx->GeometryProgram._Current, NULL);
1329
1330    _mesa_reference_program(ctx, &ctx->FragmentProgram.Current, NULL);
1331    _mesa_reference_program(ctx, &ctx->FragmentProgram._Current, NULL);
1332    _mesa_reference_program(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
1333
1334    _mesa_reference_program(ctx, &ctx->ComputeProgram._Current, NULL);
1335
1336    _mesa_reference_vao(ctx, &ctx->Array.VAO, NULL);
1337    _mesa_reference_vao(ctx, &ctx->Array.DefaultVAO, NULL);
1338
1339    _mesa_free_attrib_data(ctx);
1340    _mesa_free_buffer_objects(ctx);
1341    _mesa_free_eval_data( ctx );
1342    _mesa_free_texture_data( ctx );
1343    _mesa_free_matrix_data( ctx );
1344    _mesa_free_pipeline_data(ctx);
1345    _mesa_free_program_data(ctx);
1346    _mesa_free_shader_state(ctx);
1347    _mesa_free_queryobj_data(ctx);
1348    _mesa_free_sync_data(ctx);
1349    _mesa_free_varray_data(ctx);
1350    _mesa_free_transform_feedback(ctx);
1351    _mesa_free_performance_monitors(ctx);
1352    _mesa_free_performance_queries(ctx);
1353    _mesa_free_resident_handles(ctx);
1354
1355    _mesa_reference_buffer_object(ctx, &ctx->Pack.BufferObj, NULL);
1356    _mesa_reference_buffer_object(ctx, &ctx->Unpack.BufferObj, NULL);
1357    _mesa_reference_buffer_object(ctx, &ctx->DefaultPacking.BufferObj, NULL);
1358    _mesa_reference_buffer_object(ctx, &ctx->Array.ArrayBufferObj, NULL);
1359
1360    /* free dispatch tables */
1361    free(ctx->BeginEnd);
1362    free(ctx->OutsideBeginEnd);
1363    free(ctx->Save);
1364    free(ctx->ContextLost);
1365    free(ctx->MarshalExec);
1366
1367    /* Shared context state (display lists, textures, etc) */
1368    _mesa_reference_shared_state(ctx, &ctx->Shared, NULL);
1369
1370    /* needs to be after freeing shared state */
1371    _mesa_free_display_list_data(ctx);
1372
1373    _mesa_free_errors_data(ctx);
1374
1375    free((void *)ctx->Extensions.String);
1376
1377    free(ctx->VersionString);
1378
1379    /* unbind the context if it's currently bound */
1380    if (ctx == _mesa_get_current_context()) {
1381       _mesa_make_current(NULL, NULL, NULL);
1382    }
1383 }
1384
1385
1386 /**
1387  * Destroy a struct gl_context structure.
1388  *
1389  * \param ctx GL context.
1390  *
1391  * Calls _mesa_free_context_data() and frees the gl_context object itself.
1392  */
1393 void
1394 _mesa_destroy_context( struct gl_context *ctx )
1395 {
1396    if (ctx) {
1397       _mesa_free_context_data(ctx);
1398       free( (void *) ctx );
1399    }
1400 }
1401
1402
1403 /**
1404  * Copy attribute groups from one context to another.
1405  *
1406  * \param src source context
1407  * \param dst destination context
1408  * \param mask bitwise OR of GL_*_BIT flags
1409  *
1410  * According to the bits specified in \p mask, copies the corresponding
1411  * attributes from \p src into \p dst.  For many of the attributes a simple \c
1412  * memcpy is not enough due to the existence of internal pointers in their data
1413  * structures.
1414  */
1415 void
1416 _mesa_copy_context( const struct gl_context *src, struct gl_context *dst,
1417                     GLuint mask )
1418 {
1419    if (mask & GL_ACCUM_BUFFER_BIT) {
1420       /* OK to memcpy */
1421       dst->Accum = src->Accum;
1422    }
1423    if (mask & GL_COLOR_BUFFER_BIT) {
1424       /* OK to memcpy */
1425       dst->Color = src->Color;
1426    }
1427    if (mask & GL_CURRENT_BIT) {
1428       /* OK to memcpy */
1429       dst->Current = src->Current;
1430    }
1431    if (mask & GL_DEPTH_BUFFER_BIT) {
1432       /* OK to memcpy */
1433       dst->Depth = src->Depth;
1434    }
1435    if (mask & GL_ENABLE_BIT) {
1436       /* no op */
1437    }
1438    if (mask & GL_EVAL_BIT) {
1439       /* OK to memcpy */
1440       dst->Eval = src->Eval;
1441    }
1442    if (mask & GL_FOG_BIT) {
1443       /* OK to memcpy */
1444       dst->Fog = src->Fog;
1445    }
1446    if (mask & GL_HINT_BIT) {
1447       /* OK to memcpy */
1448       dst->Hint = src->Hint;
1449    }
1450    if (mask & GL_LIGHTING_BIT) {
1451       /* OK to memcpy */
1452       dst->Light = src->Light;
1453    }
1454    if (mask & GL_LINE_BIT) {
1455       /* OK to memcpy */
1456       dst->Line = src->Line;
1457    }
1458    if (mask & GL_LIST_BIT) {
1459       /* OK to memcpy */
1460       dst->List = src->List;
1461    }
1462    if (mask & GL_PIXEL_MODE_BIT) {
1463       /* OK to memcpy */
1464       dst->Pixel = src->Pixel;
1465    }
1466    if (mask & GL_POINT_BIT) {
1467       /* OK to memcpy */
1468       dst->Point = src->Point;
1469    }
1470    if (mask & GL_POLYGON_BIT) {
1471       /* OK to memcpy */
1472       dst->Polygon = src->Polygon;
1473    }
1474    if (mask & GL_POLYGON_STIPPLE_BIT) {
1475       /* Use loop instead of memcpy due to problem with Portland Group's
1476        * C compiler.  Reported by John Stone.
1477        */
1478       GLuint i;
1479       for (i = 0; i < 32; i++) {
1480          dst->PolygonStipple[i] = src->PolygonStipple[i];
1481       }
1482    }
1483    if (mask & GL_SCISSOR_BIT) {
1484       /* OK to memcpy */
1485       dst->Scissor = src->Scissor;
1486    }
1487    if (mask & GL_STENCIL_BUFFER_BIT) {
1488       /* OK to memcpy */
1489       dst->Stencil = src->Stencil;
1490    }
1491    if (mask & GL_TEXTURE_BIT) {
1492       /* Cannot memcpy because of pointers */
1493       _mesa_copy_texture_state(src, dst);
1494    }
1495    if (mask & GL_TRANSFORM_BIT) {
1496       /* OK to memcpy */
1497       dst->Transform = src->Transform;
1498    }
1499    if (mask & GL_VIEWPORT_BIT) {
1500       unsigned i;
1501       for (i = 0; i < src->Const.MaxViewports; i++) {
1502          /* OK to memcpy */
1503          dst->ViewportArray[i] = src->ViewportArray[i];
1504       }
1505    }
1506
1507    /* XXX FIXME:  Call callbacks?
1508     */
1509    dst->NewState = _NEW_ALL;
1510    dst->NewDriverState = ~0;
1511 }
1512
1513
1514 /**
1515  * Check if the given context can render into the given framebuffer
1516  * by checking visual attributes.
1517  *
1518  * \return GL_TRUE if compatible, GL_FALSE otherwise.
1519  */
1520 static GLboolean
1521 check_compatible(const struct gl_context *ctx,
1522                  const struct gl_framebuffer *buffer)
1523 {
1524    const struct gl_config *ctxvis = &ctx->Visual;
1525    const struct gl_config *bufvis = &buffer->Visual;
1526
1527    if (buffer == _mesa_get_incomplete_framebuffer())
1528       return GL_TRUE;
1529
1530 #define check_component(foo)           \
1531    if (ctxvis->foo && bufvis->foo &&   \
1532        ctxvis->foo != bufvis->foo)     \
1533       return GL_FALSE
1534
1535    check_component(redMask);
1536    check_component(greenMask);
1537    check_component(blueMask);
1538    check_component(depthBits);
1539    check_component(stencilBits);
1540
1541 #undef check_component
1542
1543    return GL_TRUE;
1544 }
1545
1546
1547 /**
1548  * Check if the viewport/scissor size has not yet been initialized.
1549  * Initialize the size if the given width and height are non-zero.
1550  */
1551 static void
1552 check_init_viewport(struct gl_context *ctx, GLuint width, GLuint height)
1553 {
1554    if (!ctx->ViewportInitialized && width > 0 && height > 0) {
1555       unsigned i;
1556
1557       /* Note: set flag here, before calling _mesa_set_viewport(), to prevent
1558        * potential infinite recursion.
1559        */
1560       ctx->ViewportInitialized = GL_TRUE;
1561
1562       /* Note: ctx->Const.MaxViewports may not have been set by the driver
1563        * yet, so just initialize all of them.
1564        */
1565       for (i = 0; i < MAX_VIEWPORTS; i++) {
1566          _mesa_set_viewport(ctx, i, 0, 0, width, height);
1567          _mesa_set_scissor(ctx, i, 0, 0, width, height);
1568       }
1569    }
1570 }
1571
1572
1573 static void
1574 handle_first_current(struct gl_context *ctx)
1575 {
1576    if (ctx->Version == 0 || !ctx->DrawBuffer) {
1577       /* probably in the process of tearing down the context */
1578       return;
1579    }
1580
1581    check_context_limits(ctx);
1582
1583    _mesa_update_vertex_processing_mode(ctx);
1584
1585    /* According to GL_MESA_configless_context the default value of
1586     * glDrawBuffers depends on the config of the first surface it is bound to.
1587     * For GLES it is always GL_BACK which has a magic interpretation.
1588     */
1589    if (!ctx->HasConfig && _mesa_is_desktop_gl(ctx)) {
1590       if (ctx->DrawBuffer != _mesa_get_incomplete_framebuffer()) {
1591          GLenum16 buffer;
1592
1593          if (ctx->DrawBuffer->Visual.doubleBufferMode)
1594             buffer = GL_BACK;
1595          else
1596             buffer = GL_FRONT;
1597
1598          _mesa_drawbuffers(ctx, ctx->DrawBuffer, 1, &buffer,
1599                            NULL /* destMask */);
1600       }
1601
1602       if (ctx->ReadBuffer != _mesa_get_incomplete_framebuffer()) {
1603          gl_buffer_index bufferIndex;
1604          GLenum buffer;
1605
1606          if (ctx->ReadBuffer->Visual.doubleBufferMode) {
1607             buffer = GL_BACK;
1608             bufferIndex = BUFFER_BACK_LEFT;
1609          }
1610          else {
1611             buffer = GL_FRONT;
1612             bufferIndex = BUFFER_FRONT_LEFT;
1613          }
1614
1615          _mesa_readbuffer(ctx, ctx->ReadBuffer, buffer, bufferIndex);
1616       }
1617    }
1618
1619    /* Determine if generic vertex attribute 0 aliases the conventional
1620     * glVertex position.
1621     */
1622    {
1623       const bool is_forward_compatible_context =
1624          ctx->Const.ContextFlags & GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT;
1625
1626       /* In OpenGL 3.1 attribute 0 becomes non-magic, just like in OpenGL ES
1627        * 2.0.  Note that we cannot just check for API_OPENGL_COMPAT here because
1628        * that will erroneously allow this usage in a 3.0 forward-compatible
1629        * context too.
1630        */
1631       ctx->_AttribZeroAliasesVertex = (ctx->API == API_OPENGLES
1632                                        || (ctx->API == API_OPENGL_COMPAT
1633                                            && !is_forward_compatible_context));
1634    }
1635
1636    /* We can use this to help debug user's problems.  Tell them to set
1637     * the MESA_INFO env variable before running their app.  Then the
1638     * first time each context is made current we'll print some useful
1639     * information.
1640     */
1641    if (getenv("MESA_INFO")) {
1642       _mesa_print_info(ctx);
1643    }
1644 }
1645
1646 /**
1647  * Bind the given context to the given drawBuffer and readBuffer and
1648  * make it the current context for the calling thread.
1649  * We'll render into the drawBuffer and read pixels from the
1650  * readBuffer (i.e. glRead/CopyPixels, glCopyTexImage, etc).
1651  *
1652  * We check that the context's and framebuffer's visuals are compatible
1653  * and return immediately if they're not.
1654  *
1655  * \param newCtx  the new GL context. If NULL then there will be no current GL
1656  *                context.
1657  * \param drawBuffer  the drawing framebuffer
1658  * \param readBuffer  the reading framebuffer
1659  */
1660 GLboolean
1661 _mesa_make_current( struct gl_context *newCtx,
1662                     struct gl_framebuffer *drawBuffer,
1663                     struct gl_framebuffer *readBuffer )
1664 {
1665    GET_CURRENT_CONTEXT(curCtx);
1666
1667    if (MESA_VERBOSE & VERBOSE_API)
1668       _mesa_debug(newCtx, "_mesa_make_current()\n");
1669
1670    /* Check that the context's and framebuffer's visuals are compatible.
1671     */
1672    if (newCtx && drawBuffer && newCtx->WinSysDrawBuffer != drawBuffer) {
1673       if (!check_compatible(newCtx, drawBuffer)) {
1674          _mesa_warning(newCtx,
1675               "MakeCurrent: incompatible visuals for context and drawbuffer");
1676          return GL_FALSE;
1677       }
1678    }
1679    if (newCtx && readBuffer && newCtx->WinSysReadBuffer != readBuffer) {
1680       if (!check_compatible(newCtx, readBuffer)) {
1681          _mesa_warning(newCtx,
1682               "MakeCurrent: incompatible visuals for context and readbuffer");
1683          return GL_FALSE;
1684       }
1685    }
1686
1687    if (curCtx &&
1688        (curCtx->WinSysDrawBuffer || curCtx->WinSysReadBuffer) &&
1689        /* make sure this context is valid for flushing */
1690        curCtx != newCtx &&
1691        curCtx->Const.ContextReleaseBehavior ==
1692        GL_CONTEXT_RELEASE_BEHAVIOR_FLUSH) {
1693       _mesa_flush(curCtx);
1694    }
1695
1696    /* We used to call _glapi_check_multithread() here.  Now do it in drivers */
1697
1698    if (!newCtx) {
1699       _glapi_set_dispatch(NULL);  /* none current */
1700       /* We need old ctx to correctly release Draw/ReadBuffer
1701        * and avoid a surface leak in st_renderbuffer_delete.
1702        * Therefore, first drop buffers then set new ctx to NULL.
1703        */
1704       if (curCtx) {
1705          _mesa_reference_framebuffer(&curCtx->WinSysDrawBuffer, NULL);
1706          _mesa_reference_framebuffer(&curCtx->WinSysReadBuffer, NULL);
1707       }
1708       _glapi_set_context(NULL);
1709       assert(_mesa_get_current_context() == NULL);
1710    }
1711    else {
1712       _glapi_set_context((void *) newCtx);
1713       assert(_mesa_get_current_context() == newCtx);
1714       _glapi_set_dispatch(newCtx->CurrentClientDispatch);
1715
1716       if (drawBuffer && readBuffer) {
1717          assert(_mesa_is_winsys_fbo(drawBuffer));
1718          assert(_mesa_is_winsys_fbo(readBuffer));
1719          _mesa_reference_framebuffer(&newCtx->WinSysDrawBuffer, drawBuffer);
1720          _mesa_reference_framebuffer(&newCtx->WinSysReadBuffer, readBuffer);
1721
1722          /*
1723           * Only set the context's Draw/ReadBuffer fields if they're NULL
1724           * or not bound to a user-created FBO.
1725           */
1726          if (!newCtx->DrawBuffer || _mesa_is_winsys_fbo(newCtx->DrawBuffer)) {
1727             _mesa_reference_framebuffer(&newCtx->DrawBuffer, drawBuffer);
1728             /* Update the FBO's list of drawbuffers/renderbuffers.
1729              * For winsys FBOs this comes from the GL state (which may have
1730              * changed since the last time this FBO was bound).
1731              */
1732             _mesa_update_draw_buffers(newCtx);
1733          }
1734          if (!newCtx->ReadBuffer || _mesa_is_winsys_fbo(newCtx->ReadBuffer)) {
1735             _mesa_reference_framebuffer(&newCtx->ReadBuffer, readBuffer);
1736             /* In _mesa_initialize_window_framebuffer, for single-buffered
1737              * visuals, the ColorReadBuffer is set to be GL_FRONT, even with
1738              * GLES contexts. When calling read_buffer, we verify we are reading
1739              * from GL_BACK in is_legal_es3_readbuffer_enum.  But the default is
1740              * incorrect, and certain dEQP tests check this.  So fix it here.
1741              */
1742             if (_mesa_is_gles(newCtx) &&
1743                !newCtx->ReadBuffer->Visual.doubleBufferMode)
1744                if (newCtx->ReadBuffer->ColorReadBuffer == GL_FRONT)
1745                   newCtx->ReadBuffer->ColorReadBuffer = GL_BACK;
1746          }
1747
1748          /* XXX only set this flag if we're really changing the draw/read
1749           * framebuffer bindings.
1750           */
1751          newCtx->NewState |= _NEW_BUFFERS;
1752
1753          check_init_viewport(newCtx, drawBuffer->Width, drawBuffer->Height);
1754       }
1755
1756       if (newCtx->FirstTimeCurrent) {
1757          handle_first_current(newCtx);
1758          newCtx->FirstTimeCurrent = GL_FALSE;
1759       }
1760    }
1761
1762    return GL_TRUE;
1763 }
1764
1765
1766 /**
1767  * Make context 'ctx' share the display lists, textures and programs
1768  * that are associated with 'ctxToShare'.
1769  * Any display lists, textures or programs associated with 'ctx' will
1770  * be deleted if nobody else is sharing them.
1771  */
1772 GLboolean
1773 _mesa_share_state(struct gl_context *ctx, struct gl_context *ctxToShare)
1774 {
1775    if (ctx && ctxToShare && ctx->Shared && ctxToShare->Shared) {
1776       struct gl_shared_state *oldShared = NULL;
1777
1778       /* save ref to old state to prevent it from being deleted immediately */
1779       _mesa_reference_shared_state(ctx, &oldShared, ctx->Shared);
1780
1781       /* update ctx's Shared pointer */
1782       _mesa_reference_shared_state(ctx, &ctx->Shared, ctxToShare->Shared);
1783
1784       update_default_objects(ctx);
1785
1786       /* release the old shared state */
1787       _mesa_reference_shared_state(ctx, &oldShared, NULL);
1788
1789       return GL_TRUE;
1790    }
1791    else {
1792       return GL_FALSE;
1793    }
1794 }
1795
1796
1797
1798 /**
1799  * \return pointer to the current GL context for this thread.
1800  *
1801  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1802  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in
1803  * context.h.
1804  */
1805 struct gl_context *
1806 _mesa_get_current_context( void )
1807 {
1808    return (struct gl_context *) _glapi_get_context();
1809 }
1810
1811
1812 /**
1813  * Get context's current API dispatch table.
1814  *
1815  * It'll either be the immediate-mode execute dispatcher, the display list
1816  * compile dispatcher, or the thread marshalling dispatcher.
1817  *
1818  * \param ctx GL context.
1819  *
1820  * \return pointer to dispatch_table.
1821  *
1822  * Simply returns __struct gl_contextRec::CurrentClientDispatch.
1823  */
1824 struct _glapi_table *
1825 _mesa_get_dispatch(struct gl_context *ctx)
1826 {
1827    return ctx->CurrentClientDispatch;
1828 }
1829
1830 /*@}*/
1831
1832
1833 /**********************************************************************/
1834 /** \name Miscellaneous functions                                     */
1835 /**********************************************************************/
1836 /*@{*/
1837 /**
1838  * Flush commands.
1839  */
1840 void
1841 _mesa_flush(struct gl_context *ctx)
1842 {
1843    FLUSH_VERTICES( ctx, 0 );
1844    FLUSH_CURRENT( ctx, 0 );
1845    if (ctx->Driver.Flush) {
1846       ctx->Driver.Flush(ctx);
1847    }
1848 }
1849
1850
1851
1852 /**
1853  * Flush commands and wait for completion.
1854  *
1855  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1856  * dd_function_table::Finish driver callback, if not NULL.
1857  */
1858 void GLAPIENTRY
1859 _mesa_Finish(void)
1860 {
1861    GET_CURRENT_CONTEXT(ctx);
1862    ASSERT_OUTSIDE_BEGIN_END(ctx);
1863
1864    FLUSH_VERTICES(ctx, 0);
1865    FLUSH_CURRENT(ctx, 0);
1866
1867    if (ctx->Driver.Finish) {
1868       ctx->Driver.Finish(ctx);
1869    }
1870 }
1871
1872
1873 /**
1874  * Execute glFlush().
1875  *
1876  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1877  * dd_function_table::Flush driver callback, if not NULL.
1878  */
1879 void GLAPIENTRY
1880 _mesa_Flush(void)
1881 {
1882    GET_CURRENT_CONTEXT(ctx);
1883    ASSERT_OUTSIDE_BEGIN_END(ctx);
1884    _mesa_flush(ctx);
1885 }
1886
1887
1888 /*@}*/