src/mesa/main/context.c

   1 /**
   2  * \file context.c
   3  * Mesa context/visual/framebuffer management functions.
   4  * \author Brian Paul
   5  */
   6
   7 /*
   8  * Mesa 3-D graphics library
   9  * Version:  6.5
  10  *
  11  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
  12  *
  13  * Permission is hereby granted, free of charge, to any person obtaining a
  14  * copy of this software and associated documentation files (the "Software"),
  15  * to deal in the Software without restriction, including without limitation
  16  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  17  * and/or sell copies of the Software, and to permit persons to whom the
  18  * Software is furnished to do so, subject to the following conditions:
  19  *
  20  * The above copyright notice and this permission notice shall be included
  21  * in all copies or substantial portions of the Software.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  24  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  25  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  26  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  27  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  28  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29  */
  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 "arrayobj.h"
  83 #include "attrib.h"
  84 #include "blend.h"
  85 #include "buffers.h"
  86 #include "bufferobj.h"
  87 #include "colortab.h"
  88 #include "context.h"
  89 #include "debug.h"
  90 #include "depth.h"
  91 #include "dlist.h"
  92 #include "eval.h"
  93 #include "enums.h"
  94 #include "extensions.h"
  95 #include "fbobject.h"
  96 #include "feedback.h"
  97 #include "fog.h"
  98 #include "get.h"
  99 #include "glthread.h"
 100 #include "glapioffsets.h"
 101 #include "histogram.h"
 102 #include "hint.h"
 103 #include "hash.h"
 104 #include "atifragshader.h"
 105 #include "light.h"
 106 #include "lines.h"
 107 #include "macros.h"
 108 #include "matrix.h"
 109 #include "occlude.h"
 110 #include "pixel.h"
 111 #include "points.h"
 112 #include "polygon.h"
 113 #if FEATURE_NV_vertex_program || FEATURE_NV_fragment_program
 114 #include "program.h"
 115 #endif
 116 #include "rastpos.h"
 117 #include "simple_list.h"
 118 #include "state.h"
 119 #include "stencil.h"
 120 #include "texcompress.h"
 121 #include "teximage.h"
 122 #include "texobj.h"
 123 #include "texstate.h"
 124 #include "mtypes.h"
 125 #include "varray.h"
 126 #include "version.h"
 127 #include "vtxfmt.h"
 128 #if _HAVE_FULL_GL
 129 #include "math/m_translate.h"
 130 #include "math/m_matrix.h"
 131 #include "math/m_xform.h"
 132 #include "math/mathmod.h"
 133 #endif
 134 #include "shaders.h"
 135
 136 #ifdef USE_SPARC_ASM
 137 #include "sparc/sparc.h"
 138 #endif
 139
 140 #ifndef MESA_VERBOSE
 141 int MESA_VERBOSE = 0;
 142 #endif
 143
 144 #ifndef MESA_DEBUG_FLAGS
 145 int MESA_DEBUG_FLAGS = 0;
 146 #endif
 147
 148
 149 /* ubyte -> float conversion */
 150 GLfloat _mesa_ubyte_to_float_color_tab[256];
 151
 152 static void
 153 free_shared_state( GLcontext *ctx, struct gl_shared_state *ss );
 154
 155
 156 /**********************************************************************/
 157 /** \name OpenGL SI-style interface (new in Mesa 3.5)
 158  *
 159  * \if subset
 160  * \note Most of these functions are never called in the Mesa subset.
 161  * \endif
 162  */
 163 /*@{*/
 164
 165 /**
 166  * Destroy context callback.
 167  *
 168  * \param gc context.
 169  * \return GL_TRUE on success, or GL_FALSE on failure.
 170  *
 171  * \ifnot subset
 172  * Called by window system/device driver (via __GLexports::destroyCurrent) when
 173  * the rendering context is to be destroyed.
 174  * \endif
 175  *
 176  * Frees the context data and the context structure.
 177  */
 178 GLboolean
 179 _mesa_destroyContext(__GLcontext *gc)
 180 {
 181    if (gc) {
 182       _mesa_free_context_data(gc);
 183       _mesa_free(gc);
 184    }
 185    return GL_TRUE;
 186 }
 187
 188 /**
 189  * Unbind context callback.
 190  *
 191  * \param gc context.
 192  * \return GL_TRUE on success, or GL_FALSE on failure.
 193  *
 194  * \ifnot subset
 195  * Called by window system/device driver (via __GLexports::loseCurrent)
 196  * when the rendering context is made non-current.
 197  * \endif
 198  *
 199  * No-op
 200  */
 201 GLboolean
 202 _mesa_loseCurrent(__GLcontext *gc)
 203 {
 204    /* XXX unbind context from thread */
 205    (void) gc;
 206    return GL_TRUE;
 207 }
 208
 209 /**
 210  * Bind context callback.
 211  *
 212  * \param gc context.
 213  * \return GL_TRUE on success, or GL_FALSE on failure.
 214  *
 215  * \ifnot subset
 216  * Called by window system/device driver (via __GLexports::makeCurrent)
 217  * when the rendering context is made current.
 218  * \endif
 219  *
 220  * No-op
 221  */
 222 GLboolean
 223 _mesa_makeCurrent(__GLcontext *gc)
 224 {
 225    /* XXX bind context to thread */
 226    (void) gc;
 227    return GL_TRUE;
 228 }
 229
 230 /**
 231  * Share context callback.
 232  *
 233  * \param gc context.
 234  * \param gcShare shared context.
 235  * \return GL_TRUE on success, or GL_FALSE on failure.
 236  *
 237  * \ifnot subset
 238  * Called by window system/device driver (via __GLexports::shareContext)
 239  * \endif
 240  *
 241  * Update the shared context reference count, gl_shared_state::RefCount.
 242  */
 243 GLboolean
 244 _mesa_shareContext(__GLcontext *gc, __GLcontext *gcShare)
 245 {
 246    if (gc && gcShare && gc->Shared && gcShare->Shared) {
 247       gc->Shared->RefCount--;
 248       if (gc->Shared->RefCount == 0) {
 249          free_shared_state(gc, gc->Shared);
 250       }
 251       gc->Shared = gcShare->Shared;
 252       gc->Shared->RefCount++;
 253       return GL_TRUE;
 254    }
 255    else {
 256       return GL_FALSE;
 257    }
 258 }
 259
 260
 261 #if _HAVE_FULL_GL
 262 /**
 263  * Copy context callback.
 264  */
 265 GLboolean
 266 _mesa_copyContext(__GLcontext *dst, const __GLcontext *src, GLuint mask)
 267 {
 268    if (dst && src) {
 269       _mesa_copy_context( src, dst, mask );
 270       return GL_TRUE;
 271    }
 272    else {
 273       return GL_FALSE;
 274    }
 275 }
 276 #endif
 277
 278 /** No-op */
 279 GLboolean
 280 _mesa_forceCurrent(__GLcontext *gc)
 281 {
 282    (void) gc;
 283    return GL_TRUE;
 284 }
 285
 286 /**
 287  * Windows/buffer resizing notification callback.
 288  *
 289  * \param gc GL context.
 290  * \return GL_TRUE on success, or GL_FALSE on failure.
 291  */
 292 GLboolean
 293 _mesa_notifyResize(__GLcontext *gc)
 294 {
 295    GLint x, y;
 296    GLuint width, height;
 297    __GLdrawablePrivate *d = gc->imports.getDrawablePrivate(gc);
 298    if (!d || !d->getDrawableSize)
 299       return GL_FALSE;
 300    d->getDrawableSize( d, &x, &y, &width, &height );
 301    /* update viewport, resize software buffers, etc. */
 302    return GL_TRUE;
 303 }
 304
 305 /**
 306  * Window/buffer destruction notification callback.
 307  *
 308  * \param gc GL context.
 309  *
 310  * Called when the context's window/buffer is going to be destroyed.
 311  *
 312  * No-op
 313  */
 314 void
 315 _mesa_notifyDestroy(__GLcontext *gc)
 316 {
 317    /* Unbind from it. */
 318    (void) gc;
 319 }
 320
 321 /**
 322  * Swap buffers notification callback.
 323  *
 324  * \param gc GL context.
 325  *
 326  * Called by window system just before swapping buffers.
 327  * We have to finish any pending rendering.
 328  */
 329 void
 330 _mesa_notifySwapBuffers(__GLcontext *gc)
 331 {
 332    FLUSH_VERTICES( gc, 0 );
 333 }
 334
 335 /** No-op */
 336 struct __GLdispatchStateRec *
 337 _mesa_dispatchExec(__GLcontext *gc)
 338 {
 339    (void) gc;
 340    return NULL;
 341 }
 342
 343 /** No-op */
 344 void
 345 _mesa_beginDispatchOverride(__GLcontext *gc)
 346 {
 347    (void) gc;
 348 }
 349
 350 /** No-op */
 351 void
 352 _mesa_endDispatchOverride(__GLcontext *gc)
 353 {
 354    (void) gc;
 355 }
 356
 357 /**
 358  * \ifnot subset
 359  * Setup the exports.
 360  *
 361  * The window system will call these functions when it needs Mesa to do
 362  * something.
 363  *
 364  * \note Device drivers should override these functions!  For example,
 365  * the Xlib driver should plug in the XMesa*-style functions into this
 366  * structure.  The XMesa-style functions should then call the _mesa_*
 367  * version of these functions.  This is an approximation to OO design
 368  * (inheritance and virtual functions).
 369  * \endif
 370  *
 371  * \if subset
 372  * No-op.
 373  *
 374  * \endif
 375  */
 376 static void
 377 _mesa_init_default_exports(__GLexports *exports)
 378 {
 379 #if _HAVE_FULL_GL
 380     exports->destroyContext = _mesa_destroyContext;
 381     exports->loseCurrent = _mesa_loseCurrent;
 382     exports->makeCurrent = _mesa_makeCurrent;
 383     exports->shareContext = _mesa_shareContext;
 384     exports->copyContext = _mesa_copyContext;
 385     exports->forceCurrent = _mesa_forceCurrent;
 386     exports->notifyResize = _mesa_notifyResize;
 387     exports->notifyDestroy = _mesa_notifyDestroy;
 388     exports->notifySwapBuffers = _mesa_notifySwapBuffers;
 389     exports->dispatchExec = _mesa_dispatchExec;
 390     exports->beginDispatchOverride = _mesa_beginDispatchOverride;
 391     exports->endDispatchOverride = _mesa_endDispatchOverride;
 392 #else
 393     (void) exports;
 394 #endif
 395 }
 396
 397 /**
 398  * Exported OpenGL SI interface.
 399  */
 400 __GLcontext *
 401 __glCoreCreateContext(__GLimports *imports, __GLcontextModes *modes)
 402 {
 403     GLcontext *ctx;
 404
 405     ctx = (GLcontext *) (*imports->calloc)(NULL, 1, sizeof(GLcontext));
 406     if (ctx == NULL) {
 407         return NULL;
 408     }
 409
 410     /* XXX doesn't work at this time */
 411     _mesa_initialize_context(ctx, modes, NULL, NULL, NULL);
 412     ctx->imports = *imports;
 413
 414     return ctx;
 415 }
 416
 417 /**
 418  * Exported OpenGL SI interface.
 419  */
 420 void
 421 __glCoreNopDispatch(void)
 422 {
 423 #if 0
 424    /* SI */
 425    __gl_dispatch = __glNopDispatchState;
 426 #else
 427    /* Mesa */
 428    _glapi_set_dispatch(NULL);
 429 #endif
 430 }
 431
 432 /*@}*/
 433
 434
 435 /**********************************************************************/
 436 /** \name GL Visual allocation/destruction                            */
 437 /**********************************************************************/
 438 /*@{*/
 439
 440 /**
 441  * Allocates a GLvisual structure and initializes it via
 442  * _mesa_initialize_visual().
 443  *
 444  * \param rgbFlag GL_TRUE for RGB(A) mode, GL_FALSE for Color Index mode.
 445  * \param dbFlag double buffering
 446  * \param stereoFlag stereo buffer
 447  * \param depthBits requested bits per depth buffer value. Any value in [0, 32]
 448  * is acceptable but the actual depth type will be GLushort or GLuint as
 449  * needed.
 450  * \param stencilBits requested minimum bits per stencil buffer value
 451  * \param accumRedBits, accumGreenBits, accumBlueBits, accumAlphaBits number of bits per color component in accum buffer.
 452  * \param indexBits number of bits per pixel if \p rgbFlag is GL_FALSE
 453  * \param redBits number of bits per color component in frame buffer for RGB(A)
 454  * mode.  We always use 8 in core Mesa though.
 455  * \param greenBits same as above.
 456  * \param blueBits same as above.
 457  * \param alphaBits same as above.
 458  * \param numSamples not really used.
 459  *
 460  * \return pointer to new GLvisual or NULL if requested parameters can't be
 461  * met.
 462  *
 463  * \note Need to add params for level and numAuxBuffers (at least)
 464  */
 465 GLvisual *
 466 _mesa_create_visual( GLboolean rgbFlag,
 467                      GLboolean dbFlag,
 468                      GLboolean stereoFlag,
 469                      GLint redBits,
 470                      GLint greenBits,
 471                      GLint blueBits,
 472                      GLint alphaBits,
 473                      GLint indexBits,
 474                      GLint depthBits,
 475                      GLint stencilBits,
 476                      GLint accumRedBits,
 477                      GLint accumGreenBits,
 478                      GLint accumBlueBits,
 479                      GLint accumAlphaBits,
 480                      GLint numSamples )
 481 {
 482    GLvisual *vis = (GLvisual *) _mesa_calloc(sizeof(GLvisual));
 483    if (vis) {
 484       if (!_mesa_initialize_visual(vis, rgbFlag, dbFlag, stereoFlag,
 485                                    redBits, greenBits, blueBits, alphaBits,
 486                                    indexBits, depthBits, stencilBits,
 487                                    accumRedBits, accumGreenBits,
 488                                    accumBlueBits, accumAlphaBits,
 489                                    numSamples)) {
 490          _mesa_free(vis);
 491          return NULL;
 492       }
 493    }
 494    return vis;
 495 }
 496
 497 /**
 498  * Makes some sanity checks and fills in the fields of the
 499  * GLvisual object with the given parameters.  If the caller needs
 500  * to set additional fields, he should just probably init the whole GLvisual
 501  * object himself.
 502  * \return GL_TRUE on success, or GL_FALSE on failure.
 503  *
 504  * \sa _mesa_create_visual() above for the parameter description.
 505  */
 506 GLboolean
 507 _mesa_initialize_visual( GLvisual *vis,
 508                          GLboolean rgbFlag,
 509                          GLboolean dbFlag,
 510                          GLboolean stereoFlag,
 511                          GLint redBits,
 512                          GLint greenBits,
 513                          GLint blueBits,
 514                          GLint alphaBits,
 515                          GLint indexBits,
 516                          GLint depthBits,
 517                          GLint stencilBits,
 518                          GLint accumRedBits,
 519                          GLint accumGreenBits,
 520                          GLint accumBlueBits,
 521                          GLint accumAlphaBits,
 522                          GLint numSamples )
 523 {
 524    assert(vis);
 525
 526    if (depthBits < 0 || depthBits > 32) {
 527       return GL_FALSE;
 528    }
 529    if (stencilBits < 0 || stencilBits > STENCIL_BITS) {
 530       return GL_FALSE;
 531    }
 532    assert(accumRedBits >= 0);
 533    assert(accumGreenBits >= 0);
 534    assert(accumBlueBits >= 0);
 535    assert(accumAlphaBits >= 0);
 536
 537    vis->rgbMode          = rgbFlag;
 538    vis->doubleBufferMode = dbFlag;
 539    vis->stereoMode       = stereoFlag;
 540
 541    vis->redBits          = redBits;
 542    vis->greenBits        = greenBits;
 543    vis->blueBits         = blueBits;
 544    vis->alphaBits        = alphaBits;
 545    vis->rgbBits          = redBits + greenBits + blueBits;
 546
 547    vis->indexBits      = indexBits;
 548    vis->depthBits      = depthBits;
 549    vis->stencilBits    = stencilBits;
 550
 551    vis->accumRedBits   = accumRedBits;
 552    vis->accumGreenBits = accumGreenBits;
 553    vis->accumBlueBits  = accumBlueBits;
 554    vis->accumAlphaBits = accumAlphaBits;
 555
 556    vis->haveAccumBuffer   = accumRedBits > 0;
 557    vis->haveDepthBuffer   = depthBits > 0;
 558    vis->haveStencilBuffer = stencilBits > 0;
 559
 560    vis->numAuxBuffers = 0;
 561    vis->level = 0;
 562    vis->pixmapMode = 0;
 563    vis->sampleBuffers = numSamples > 0 ? 1 : 0;
 564    vis->samples = numSamples;
 565
 566    return GL_TRUE;
 567 }
 568
 569
 570 /**
 571  * Destroy a visual and free its memory.
 572  *
 573  * \param vis visual.
 574  *
 575  * Frees the visual structure.
 576  */
 577 void
 578 _mesa_destroy_visual( GLvisual *vis )
 579 {
 580    _mesa_free(vis);
 581 }
 582
 583 /*@}*/
 584
 585
 586 /**********************************************************************/
 587 /** \name Context allocation, initialization, destroying
 588  *
 589  * The purpose of the most initialization functions here is to provide the
 590  * default state values according to the OpenGL specification.
 591  */
 592 /**********************************************************************/
 593 /*@{*/
 594
 595 /**
 596  * One-time initialization mutex lock.
 597  *
 598  * \sa Used by one_time_init().
 599  */
 600 _glthread_DECLARE_STATIC_MUTEX(OneTimeLock);
 601
 602 /**
 603  * Calls all the various one-time-init functions in Mesa.
 604  *
 605  * While holding a global mutex lock, calls several initialization functions,
 606  * and sets the glapi callbacks if the \c MESA_DEBUG environment variable is
 607  * defined.
 608  *
 609  * \sa _math_init().
 610  */
 611 static void
 612 one_time_init( GLcontext *ctx )
 613 {
 614    static GLboolean alreadyCalled = GL_FALSE;
 615    (void) ctx;
 616    _glthread_LOCK_MUTEX(OneTimeLock);
 617    if (!alreadyCalled) {
 618       GLuint i;
 619
 620       /* do some implementation tests */
 621       assert( sizeof(GLbyte) == 1 );
 622       assert( sizeof(GLubyte) == 1 );
 623       assert( sizeof(GLshort) == 2 );
 624       assert( sizeof(GLushort) == 2 );
 625       assert( sizeof(GLint) == 4 );
 626       assert( sizeof(GLuint) == 4 );
 627
 628 #if _HAVE_FULL_GL
 629       _math_init();
 630
 631       for (i = 0; i < 256; i++) {
 632          _mesa_ubyte_to_float_color_tab[i] = (float) i / 255.0F;
 633       }
 634 #endif
 635
 636 #ifdef USE_SPARC_ASM
 637       _mesa_init_sparc_glapi_relocs();
 638 #endif
 639       if (_mesa_getenv("MESA_DEBUG")) {
 640          _glapi_noop_enable_warnings(GL_TRUE);
 641          _glapi_set_warning_func( (_glapi_warning_func) _mesa_warning );
 642       }
 643       else {
 644          _glapi_noop_enable_warnings(GL_FALSE);
 645       }
 646
 647 #if defined(DEBUG) && defined(__DATE__) && defined(__TIME__)
 648       _mesa_debug(ctx, "Mesa %s DEBUG build %s %s\n",
 649                   MESA_VERSION_STRING, __DATE__, __TIME__);
 650 #endif
 651
 652       alreadyCalled = GL_TRUE;
 653    }
 654    _glthread_UNLOCK_MUTEX(OneTimeLock);
 655 }
 656
 657
 658 /**
 659  * Allocate and initialize a shared context state structure.
 660  * Initializes the display list, texture objects and vertex programs hash
 661  * tables, allocates the texture objects. If it runs out of memory, frees
 662  * everything already allocated before returning NULL.
 663  *
 664  * \return pointer to a gl_shared_state structure on success, or NULL on
 665  * failure.
 666  */
 667 static GLboolean
 668 alloc_shared_state( GLcontext *ctx )
 669 {
 670    struct gl_shared_state *ss = CALLOC_STRUCT(gl_shared_state);
 671    if (!ss)
 672       return GL_FALSE;
 673
 674    ctx->Shared = ss;
 675
 676    _glthread_INIT_MUTEX(ss->Mutex);
 677
 678    ss->DisplayList = _mesa_NewHashTable();
 679    ss->TexObjects = _mesa_NewHashTable();
 680 #if FEATURE_NV_vertex_program || FEATURE_NV_fragment_program
 681    ss->Programs = _mesa_NewHashTable();
 682 #endif
 683
 684 #if FEATURE_ARB_vertex_program
 685    ss->DefaultVertexProgram = ctx->Driver.NewProgram(ctx, GL_VERTEX_PROGRAM_ARB, 0);
 686    if (!ss->DefaultVertexProgram)
 687       goto cleanup;
 688 #endif
 689 #if FEATURE_ARB_fragment_program
 690    ss->DefaultFragmentProgram = ctx->Driver.NewProgram(ctx, GL_FRAGMENT_PROGRAM_ARB, 0);
 691    if (!ss->DefaultFragmentProgram)
 692       goto cleanup;
 693 #endif
 694 #if FEATURE_ATI_fragment_shader
 695    ss->ATIShaders = _mesa_NewHashTable();
 696    ss->DefaultFragmentShader = _mesa_new_ati_fragment_shader(ctx, 0);
 697    if (!ss->DefaultFragmentShader)
 698       goto cleanup;
 699 #endif
 700
 701 #if FEATURE_ARB_vertex_buffer_object || FEATURE_ARB_pixel_buffer_object
 702    ss->BufferObjects = _mesa_NewHashTable();
 703 #endif
 704
 705    ss->ArrayObjects = _mesa_NewHashTable();
 706
 707 #if FEATURE_ARB_shader_objects
 708    ss->ShaderObjects = _mesa_NewHashTable();
 709 #endif
 710
 711    ss->Default1D = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_1D);
 712    if (!ss->Default1D)
 713       goto cleanup;
 714
 715    ss->Default2D = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_2D);
 716    if (!ss->Default2D)
 717       goto cleanup;
 718
 719    ss->Default3D = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_3D);
 720    if (!ss->Default3D)
 721       goto cleanup;
 722
 723    ss->DefaultCubeMap = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_CUBE_MAP_ARB);
 724    if (!ss->DefaultCubeMap)
 725       goto cleanup;
 726
 727    ss->DefaultRect = (*ctx->Driver.NewTextureObject)(ctx, 0, GL_TEXTURE_RECTANGLE_NV);
 728    if (!ss->DefaultRect)
 729       goto cleanup;
 730
 731    /* Effectively bind the default textures to all texture units */
 732    ss->Default1D->RefCount += MAX_TEXTURE_IMAGE_UNITS;
 733    ss->Default2D->RefCount += MAX_TEXTURE_IMAGE_UNITS;
 734    ss->Default3D->RefCount += MAX_TEXTURE_IMAGE_UNITS;
 735    ss->DefaultCubeMap->RefCount += MAX_TEXTURE_IMAGE_UNITS;
 736    ss->DefaultRect->RefCount += MAX_TEXTURE_IMAGE_UNITS;
 737
 738    _glthread_INIT_MUTEX(ss->TexMutex);
 739    ss->TextureStateStamp = 0;
 740
 741
 742 #if FEATURE_EXT_framebuffer_object
 743    ss->FrameBuffers = _mesa_NewHashTable();
 744    if (!ss->FrameBuffers)
 745       goto cleanup;
 746    ss->RenderBuffers = _mesa_NewHashTable();
 747    if (!ss->RenderBuffers)
 748       goto cleanup;
 749 #endif
 750
 751
 752    return GL_TRUE;
 753
 754  cleanup:
 755    /* Ran out of memory at some point.  Free everything and return NULL */
 756    if (ss->DisplayList)
 757       _mesa_DeleteHashTable(ss->DisplayList);
 758    if (ss->TexObjects)
 759       _mesa_DeleteHashTable(ss->TexObjects);
 760 #if FEATURE_NV_vertex_program
 761    if (ss->Programs)
 762       _mesa_DeleteHashTable(ss->Programs);
 763 #endif
 764 #if FEATURE_ARB_vertex_program
 765    if (ss->DefaultVertexProgram)
 766       ctx->Driver.DeleteProgram(ctx, ss->DefaultVertexProgram);
 767 #endif
 768 #if FEATURE_ARB_fragment_program
 769    if (ss->DefaultFragmentProgram)
 770       ctx->Driver.DeleteProgram(ctx, ss->DefaultFragmentProgram);
 771 #endif
 772 #if FEATURE_ATI_fragment_shader
 773    if (ss->DefaultFragmentShader)
 774       _mesa_delete_ati_fragment_shader(ctx, ss->DefaultFragmentShader);
 775 #endif
 776 #if FEATURE_ARB_vertex_buffer_object || FEATURE_ARB_pixel_buffer_object
 777    if (ss->BufferObjects)
 778       _mesa_DeleteHashTable(ss->BufferObjects);
 779 #endif
 780
 781    if (ss->ArrayObjects)
 782       _mesa_DeleteHashTable (ss->ArrayObjects);
 783
 784 #if FEATURE_ARB_shader_objects
 785    if (ss->ShaderObjects)
 786       _mesa_DeleteHashTable (ss->ShaderObjects);
 787 #endif
 788
 789 #if FEATURE_EXT_framebuffer_object
 790    if (ss->FrameBuffers)
 791       _mesa_DeleteHashTable(ss->FrameBuffers);
 792    if (ss->RenderBuffers)
 793       _mesa_DeleteHashTable(ss->RenderBuffers);
 794 #endif
 795
 796    if (ss->Default1D)
 797       (*ctx->Driver.DeleteTexture)(ctx, ss->Default1D);
 798    if (ss->Default2D)
 799       (*ctx->Driver.DeleteTexture)(ctx, ss->Default2D);
 800    if (ss->Default3D)
 801       (*ctx->Driver.DeleteTexture)(ctx, ss->Default3D);
 802    if (ss->DefaultCubeMap)
 803       (*ctx->Driver.DeleteTexture)(ctx, ss->DefaultCubeMap);
 804    if (ss->DefaultRect)
 805       (*ctx->Driver.DeleteTexture)(ctx, ss->DefaultRect);
 806    if (ss)
 807       _mesa_free(ss);
 808    return GL_FALSE;
 809 }
 810
 811
 812 /**
 813  * Callback for deleting a display list.  Called by _mesa_HashDeleteAll().
 814  */
 815 static void
 816 delete_displaylist_cb(GLuint id, void *data, void *userData)
 817 {
 818    struct mesa_display_list *list = (struct mesa_display_list *) data;
 819    GLcontext *ctx = (GLcontext *) userData;
 820    _mesa_delete_list(ctx, list);
 821 }
 822
 823 /**
 824  * Callback for deleting a texture object.  Called by _mesa_HashDeleteAll().
 825  */
 826 static void
 827 delete_texture_cb(GLuint id, void *data, void *userData)
 828 {
 829    struct gl_texture_object *texObj = (struct gl_texture_object *) data;
 830    GLcontext *ctx = (GLcontext *) userData;
 831    ctx->Driver.DeleteTexture(ctx, texObj);
 832 }
 833
 834 /**
 835  * Callback for deleting a program object.  Called by _mesa_HashDeleteAll().
 836  */
 837 static void
 838 delete_program_cb(GLuint id, void *data, void *userData)
 839 {
 840    struct gl_program *prog = (struct gl_program *) data;
 841    GLcontext *ctx = (GLcontext *) userData;
 842    ctx->Driver.DeleteProgram(ctx, prog);
 843 }
 844
 845 /**
 846  * Callback for deleting an ATI fragment shader object.
 847  * Called by _mesa_HashDeleteAll().
 848  */
 849 static void
 850 delete_fragshader_cb(GLuint id, void *data, void *userData)
 851 {
 852    struct ati_fragment_shader *shader = (struct ati_fragment_shader *) data;
 853    GLcontext *ctx = (GLcontext *) userData;
 854    _mesa_delete_ati_fragment_shader(ctx, shader);
 855 }
 856
 857 /**
 858  * Callback for deleting a buffer object.  Called by _mesa_HashDeleteAll().
 859  */
 860 static void
 861 delete_bufferobj_cb(GLuint id, void *data, void *userData)
 862 {
 863    struct gl_buffer_object *bufObj = (struct gl_buffer_object *) data;
 864    GLcontext *ctx = (GLcontext *) userData;
 865    ctx->Driver.DeleteBuffer(ctx, bufObj);
 866 }
 867
 868 /**
 869  * Callback for deleting an array object.  Called by _mesa_HashDeleteAll().
 870  */
 871 static void
 872 delete_arrayobj_cb(GLuint id, void *data, void *userData)
 873 {
 874    struct gl_array_object *arrayObj = (struct gl_array_object *) data;
 875    GLcontext *ctx = (GLcontext *) userData;
 876    _mesa_delete_array_object(ctx, arrayObj);
 877 }
 878
 879 /**
 880  * Callback for deleting an shader object.  Called by _mesa_HashDeleteAll().
 881  */
 882 static void
 883 delete_shaderobj_cb(GLuint id, void *data, void *userData)
 884 {
 885    /* XXX probably need to fix this */
 886    _mesa_free(data);
 887 }
 888
 889
 890 /**
 891  * Deallocate a shared state object and all children structures.
 892  *
 893  * \param ctx GL context.
 894  * \param ss shared state pointer.
 895  *
 896  * Frees the display lists, the texture objects (calling the driver texture
 897  * deletion callback to free its private data) and the vertex programs, as well
 898  * as their hash tables.
 899  *
 900  * \sa alloc_shared_state().
 901  */
 902 static void
 903 free_shared_state( GLcontext *ctx, struct gl_shared_state *ss )
 904 {
 905    /*
 906     * Free display lists
 907     */
 908    _mesa_HashDeleteAll(ss->DisplayList, delete_displaylist_cb, ctx);
 909    _mesa_DeleteHashTable(ss->DisplayList);
 910
 911    /*
 912     * Free texture objects
 913     */
 914    ASSERT(ctx->Driver.DeleteTexture);
 915    /* the default textures */
 916    ctx->Driver.DeleteTexture(ctx, ss->Default1D);
 917    ctx->Driver.DeleteTexture(ctx, ss->Default2D);
 918    ctx->Driver.DeleteTexture(ctx, ss->Default3D);
 919    ctx->Driver.DeleteTexture(ctx, ss->DefaultCubeMap);
 920    ctx->Driver.DeleteTexture(ctx, ss->DefaultRect);
 921    /* all other textures */
 922    _mesa_HashDeleteAll(ss->TexObjects, delete_texture_cb, ctx);
 923    _mesa_DeleteHashTable(ss->TexObjects);
 924
 925 #if defined(FEATURE_NV_vertex_program) || defined(FEATURE_NV_fragment_program)
 926    _mesa_HashDeleteAll(ss->Programs, delete_program_cb, ctx);
 927    _mesa_DeleteHashTable(ss->Programs);
 928 #endif
 929 #if FEATURE_ARB_vertex_program
 930    _mesa_delete_program(ctx, ss->DefaultVertexProgram);
 931 #endif
 932 #if FEATURE_ARB_fragment_program
 933    _mesa_delete_program(ctx, ss->DefaultFragmentProgram);
 934 #endif
 935
 936 #if FEATURE_ATI_fragment_shader
 937    _mesa_HashDeleteAll(ss->ATIShaders, delete_fragshader_cb, ctx);
 938    _mesa_DeleteHashTable(ss->ATIShaders);
 939    _mesa_delete_ati_fragment_shader(ctx, ss->DefaultFragmentShader);
 940 #endif
 941
 942 #if FEATURE_ARB_vertex_buffer_object || FEATURE_ARB_pixel_buffer_object
 943    _mesa_HashDeleteAll(ss->BufferObjects, delete_bufferobj_cb, ctx);
 944    _mesa_DeleteHashTable(ss->BufferObjects);
 945 #endif
 946
 947    _mesa_HashDeleteAll(ss->ArrayObjects, delete_arrayobj_cb, ctx);
 948    _mesa_DeleteHashTable(ss->ArrayObjects);
 949
 950 #if FEATURE_ARB_shader_objects
 951    /* XXX SLANG TO-DO */
 952    /*
 953    struct _mesa_HashTable *ShaderObjects;
 954    struct _mesa_HashTable *ProgramObjects;
 955    */
 956 #endif
 957
 958 #if FEATURE_EXT_framebuffer_object
 959    _mesa_DeleteHashTable(ss->FrameBuffers);
 960    _mesa_DeleteHashTable(ss->RenderBuffers);
 961 #endif
 962
 963    _glthread_DESTROY_MUTEX(ss->Mutex);
 964
 965    _mesa_free(ss);
 966 }
 967
 968
 969 /**
 970  * Initialize fields of gl_current_attrib (aka ctx->Current.*)
 971  */
 972 static void
 973 _mesa_init_current( GLcontext *ctx )
 974 {
 975    GLuint i;
 976
 977    /* Init all to (0,0,0,1) */
 978    for (i = 0; i < VERT_ATTRIB_MAX; i++) {
 979       ASSIGN_4V( ctx->Current.Attrib[i], 0.0, 0.0, 0.0, 1.0 );
 980    }
 981
 982    /* redo special cases: */
 983    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_WEIGHT], 1.0, 0.0, 0.0, 1.0 );
 984    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_NORMAL], 0.0, 0.0, 1.0, 1.0 );
 985    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR0], 1.0, 1.0, 1.0, 1.0 );
 986    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR1], 0.0, 0.0, 0.0, 1.0 );
 987    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_FOG], 0.0, 0.0, 0.0, 0.0 );
 988    ctx->Current.Attrib[VERT_ATTRIB_COLOR_INDEX][0] = 1.0;
 989    ctx->Current.EdgeFlag = GL_TRUE;
 990 }
 991
 992
 993 /**
 994  * Init vertex/fragment program native limits from logical limits.
 995  */
 996 static void
 997 init_natives(struct gl_program_constants *prog)
 998 {
 999    prog->MaxNativeInstructions = prog->MaxInstructions;
1000    prog->MaxNativeAluInstructions = prog->MaxAluInstructions;
1001    prog->MaxNativeTexInstructions = prog->MaxTexInstructions;
1002    prog->MaxNativeTexIndirections = prog->MaxTexIndirections;
1003    prog->MaxNativeAttribs = prog->MaxAttribs;
1004    prog->MaxNativeTemps = prog->MaxTemps;
1005    prog->MaxNativeAddressRegs = prog->MaxAddressRegs;
1006    prog->MaxNativeParameters = prog->MaxParameters;
1007 }
1008
1009
1010 /**
1011  * Initialize fields of gl_constants (aka ctx->Const.*).
1012  * Use defaults from config.h.  The device drivers will often override
1013  * some of these values (such as number of texture units).
1014  */
1015 static void
1016 _mesa_init_constants( GLcontext *ctx )
1017 {
1018    assert(ctx);
1019
1020    assert(MAX_TEXTURE_LEVELS >= MAX_3D_TEXTURE_LEVELS);
1021    assert(MAX_TEXTURE_LEVELS >= MAX_CUBE_TEXTURE_LEVELS);
1022
1023    assert(MAX_TEXTURE_UNITS >= MAX_TEXTURE_COORD_UNITS);
1024    assert(MAX_TEXTURE_UNITS >= MAX_TEXTURE_IMAGE_UNITS);
1025
1026    /* Constants, may be overriden (usually only reduced) by device drivers */
1027    ctx->Const.MaxTextureLevels = MAX_TEXTURE_LEVELS;
1028    ctx->Const.Max3DTextureLevels = MAX_3D_TEXTURE_LEVELS;
1029    ctx->Const.MaxCubeTextureLevels = MAX_CUBE_TEXTURE_LEVELS;
1030    ctx->Const.MaxTextureRectSize = MAX_TEXTURE_RECT_SIZE;
1031    ctx->Const.MaxTextureCoordUnits = MAX_TEXTURE_COORD_UNITS;
1032    ctx->Const.MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
1033    ctx->Const.MaxTextureUnits = MIN2(ctx->Const.MaxTextureCoordUnits,
1034                                      ctx->Const.MaxTextureImageUnits);
1035    ctx->Const.MaxTextureMaxAnisotropy = MAX_TEXTURE_MAX_ANISOTROPY;
1036    ctx->Const.MaxTextureLodBias = MAX_TEXTURE_LOD_BIAS;
1037    ctx->Const.MaxArrayLockSize = MAX_ARRAY_LOCK_SIZE;
1038    ctx->Const.SubPixelBits = SUB_PIXEL_BITS;
1039    ctx->Const.MinPointSize = MIN_POINT_SIZE;
1040    ctx->Const.MaxPointSize = MAX_POINT_SIZE;
1041    ctx->Const.MinPointSizeAA = MIN_POINT_SIZE;
1042    ctx->Const.MaxPointSizeAA = MAX_POINT_SIZE;
1043    ctx->Const.PointSizeGranularity = (GLfloat) POINT_SIZE_GRANULARITY;
1044    ctx->Const.MinLineWidth = MIN_LINE_WIDTH;
1045    ctx->Const.MaxLineWidth = MAX_LINE_WIDTH;
1046    ctx->Const.MinLineWidthAA = MIN_LINE_WIDTH;
1047    ctx->Const.MaxLineWidthAA = MAX_LINE_WIDTH;
1048    ctx->Const.LineWidthGranularity = (GLfloat) LINE_WIDTH_GRANULARITY;
1049    ctx->Const.MaxColorTableSize = MAX_COLOR_TABLE_SIZE;
1050    ctx->Const.MaxConvolutionWidth = MAX_CONVOLUTION_WIDTH;
1051    ctx->Const.MaxConvolutionHeight = MAX_CONVOLUTION_HEIGHT;
1052    ctx->Const.MaxClipPlanes = MAX_CLIP_PLANES;
1053    ctx->Const.MaxLights = MAX_LIGHTS;
1054    ctx->Const.MaxShininess = 128.0;
1055    ctx->Const.MaxSpotExponent = 128.0;
1056    ctx->Const.MaxViewportWidth = MAX_WIDTH;
1057    ctx->Const.MaxViewportHeight = MAX_HEIGHT;
1058 #if FEATURE_ARB_vertex_program
1059    ctx->Const.VertexProgram.MaxInstructions = MAX_NV_VERTEX_PROGRAM_INSTRUCTIONS;
1060    ctx->Const.VertexProgram.MaxAluInstructions = 0;
1061    ctx->Const.VertexProgram.MaxTexInstructions = 0;
1062    ctx->Const.VertexProgram.MaxTexIndirections = 0;
1063    ctx->Const.VertexProgram.MaxAttribs = MAX_NV_VERTEX_PROGRAM_INPUTS;
1064    ctx->Const.VertexProgram.MaxTemps = MAX_NV_VERTEX_PROGRAM_TEMPS;
1065    ctx->Const.VertexProgram.MaxParameters = MAX_NV_VERTEX_PROGRAM_PARAMS;
1066    ctx->Const.VertexProgram.MaxLocalParams = MAX_PROGRAM_LOCAL_PARAMS;
1067    ctx->Const.VertexProgram.MaxEnvParams = MAX_NV_VERTEX_PROGRAM_PARAMS;
1068    ctx->Const.VertexProgram.MaxAddressRegs = MAX_VERTEX_PROGRAM_ADDRESS_REGS;
1069    ctx->Const.VertexProgram.MaxUniformComponents = 4 * MAX_UNIFORMS;
1070    init_natives(&ctx->Const.VertexProgram);
1071 #endif
1072
1073 #if FEATURE_ARB_fragment_program
1074    ctx->Const.FragmentProgram.MaxInstructions = MAX_NV_FRAGMENT_PROGRAM_INSTRUCTIONS;
1075    ctx->Const.FragmentProgram.MaxAluInstructions = MAX_FRAGMENT_PROGRAM_ALU_INSTRUCTIONS;
1076    ctx->Const.FragmentProgram.MaxTexInstructions = MAX_FRAGMENT_PROGRAM_TEX_INSTRUCTIONS;
1077    ctx->Const.FragmentProgram.MaxTexIndirections = MAX_FRAGMENT_PROGRAM_TEX_INDIRECTIONS;
1078    ctx->Const.FragmentProgram.MaxAttribs = MAX_NV_FRAGMENT_PROGRAM_INPUTS;
1079    ctx->Const.FragmentProgram.MaxTemps = MAX_NV_FRAGMENT_PROGRAM_TEMPS;
1080    ctx->Const.FragmentProgram.MaxParameters = MAX_NV_FRAGMENT_PROGRAM_PARAMS;
1081    ctx->Const.FragmentProgram.MaxLocalParams = MAX_PROGRAM_LOCAL_PARAMS;
1082    ctx->Const.FragmentProgram.MaxEnvParams = MAX_NV_FRAGMENT_PROGRAM_PARAMS;
1083    ctx->Const.FragmentProgram.MaxAddressRegs = MAX_FRAGMENT_PROGRAM_ADDRESS_REGS;
1084    ctx->Const.FragmentProgram.MaxUniformComponents = 4 * MAX_UNIFORMS;
1085    init_natives(&ctx->Const.FragmentProgram);
1086 #endif
1087    ctx->Const.MaxProgramMatrices = MAX_PROGRAM_MATRICES;
1088    ctx->Const.MaxProgramMatrixStackDepth = MAX_PROGRAM_MATRIX_STACK_DEPTH;
1089
1090    /* If we're running in the X server, do bounds checking to prevent
1091     * segfaults and server crashes!
1092     */
1093 #if defined(XFree86Server)
1094    ctx->Const.CheckArrayBounds = GL_TRUE;
1095 #else
1096    ctx->Const.CheckArrayBounds = GL_FALSE;
1097 #endif
1098
1099    /* GL_ARB_draw_buffers */
1100    ctx->Const.MaxDrawBuffers = MAX_DRAW_BUFFERS;
1101
1102    /* GL_OES_read_format */
1103    ctx->Const.ColorReadFormat = GL_RGBA;
1104    ctx->Const.ColorReadType = GL_UNSIGNED_BYTE;
1105
1106 #if FEATURE_EXT_framebuffer_object
1107    ctx->Const.MaxColorAttachments = MAX_COLOR_ATTACHMENTS;
1108    ctx->Const.MaxRenderbufferSize = MAX_WIDTH;
1109 #endif
1110
1111 #if FEATURE_ARB_vertex_shader
1112    ctx->Const.MaxVertexTextureImageUnits = MAX_VERTEX_TEXTURE_IMAGE_UNITS;
1113    ctx->Const.MaxVarying = MAX_VARYING;
1114 #endif
1115
1116    /* sanity checks */
1117    ASSERT(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.MaxTextureImageUnits,
1118                                              ctx->Const.MaxTextureCoordUnits));
1119    ASSERT(ctx->Const.FragmentProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
1120    ASSERT(ctx->Const.VertexProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
1121
1122    ASSERT(MAX_NV_FRAGMENT_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
1123    ASSERT(MAX_NV_VERTEX_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
1124    ASSERT(MAX_NV_VERTEX_PROGRAM_INPUTS <= VERT_ATTRIB_MAX);
1125    ASSERT(MAX_NV_VERTEX_PROGRAM_OUTPUTS <= VERT_RESULT_MAX);
1126 }
1127
1128
1129 /**
1130  * Do some sanity checks on the limits/constants for the given context.
1131  * Only called the first time a context is bound.
1132  */
1133 static void
1134 check_context_limits(GLcontext *ctx)
1135 {
1136    /* Many context limits/constants are limited by the size of
1137     * internal arrays.
1138     */
1139    assert(ctx->Const.MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
1140    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
1141    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
1142    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
1143
1144    assert(ctx->Const.MaxViewportWidth <= MAX_WIDTH);
1145    assert(ctx->Const.MaxViewportHeight <= MAX_WIDTH);
1146
1147    /* make sure largest texture image is <= MAX_WIDTH in size */
1148    assert((1 << (ctx->Const.MaxTextureLevels -1 )) <= MAX_WIDTH);
1149    assert((1 << (ctx->Const.MaxCubeTextureLevels -1 )) <= MAX_WIDTH);
1150    assert((1 << (ctx->Const.Max3DTextureLevels -1 )) <= MAX_WIDTH);
1151
1152    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
1153
1154    /* XXX probably add more tests */
1155 }
1156
1157
1158 /**
1159  * Initialize the attribute groups in a GL context.
1160  *
1161  * \param ctx GL context.
1162  *
1163  * Initializes all the attributes, calling the respective <tt>init*</tt>
1164  * functions for the more complex data structures.
1165  */
1166 static GLboolean
1167 init_attrib_groups( GLcontext *ctx )
1168 {
1169    assert(ctx);
1170
1171    /* Constants */
1172    _mesa_init_constants( ctx );
1173
1174    /* Extensions */
1175    _mesa_init_extensions( ctx );
1176
1177    /* Attribute Groups */
1178    _mesa_init_accum( ctx );
1179    _mesa_init_attrib( ctx );
1180    _mesa_init_buffer_objects( ctx );
1181    _mesa_init_color( ctx );
1182    _mesa_init_colortables( ctx );
1183    _mesa_init_current( ctx );
1184    _mesa_init_depth( ctx );
1185    _mesa_init_debug( ctx );
1186    _mesa_init_display_list( ctx );
1187    _mesa_init_eval( ctx );
1188    _mesa_init_feedback( ctx );
1189    _mesa_init_fog( ctx );
1190    _mesa_init_histogram( ctx );
1191    _mesa_init_hint( ctx );
1192    _mesa_init_line( ctx );
1193    _mesa_init_lighting( ctx );
1194    _mesa_init_matrix( ctx );
1195    _mesa_init_multisample( ctx );
1196    _mesa_init_pixel( ctx );
1197    _mesa_init_point( ctx );
1198    _mesa_init_polygon( ctx );
1199    _mesa_init_program( ctx );
1200    _mesa_init_query( ctx );
1201    _mesa_init_rastpos( ctx );
1202    _mesa_init_scissor( ctx );
1203    _mesa_init_shader_state( ctx );
1204    _mesa_init_stencil( ctx );
1205    _mesa_init_transform( ctx );
1206    _mesa_init_varray( ctx );
1207    _mesa_init_viewport( ctx );
1208
1209    if (!_mesa_init_texture( ctx ))
1210       return GL_FALSE;
1211
1212    _mesa_init_texture_s3tc( ctx );
1213    _mesa_init_texture_fxt1( ctx );
1214
1215    /* Miscellaneous */
1216    ctx->NewState = _NEW_ALL;
1217    ctx->ErrorValue = (GLenum) GL_NO_ERROR;
1218    ctx->_Facing = 0;
1219
1220    return GL_TRUE;
1221 }
1222
1223
1224 /**
1225  * This is the default function we plug into all dispatch table slots
1226  * This helps prevents a segfault when someone calls a GL function without
1227  * first checking if the extension's supported.
1228  */
1229 static int
1230 generic_nop(void)
1231 {
1232    _mesa_problem(NULL, "User called no-op dispatch function (an unsupported extension function?)");
1233    return 0;
1234 }
1235
1236
1237 /**
1238  * Allocate and initialize a new dispatch table.
1239  */
1240 static struct _glapi_table *
1241 alloc_dispatch_table(void)
1242 {
1243    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
1244     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
1245     * Mesa we do this to accomodate different versions of libGL and various
1246     * DRI drivers.
1247     */
1248    GLint numEntries = MAX2(_glapi_get_dispatch_table_size(),
1249                            sizeof(struct _glapi_table) / sizeof(_glapi_proc));
1250    struct _glapi_table *table =
1251       (struct _glapi_table *) _mesa_malloc(numEntries * sizeof(_glapi_proc));
1252    if (table) {
1253       _glapi_proc *entry = (_glapi_proc *) table;
1254       GLint i;
1255       for (i = 0; i < numEntries; i++) {
1256          entry[i] = (_glapi_proc) generic_nop;
1257       }
1258    }
1259    return table;
1260 }
1261
1262
1263 /**
1264  * Initialize a GLcontext struct (rendering context).
1265  *
1266  * This includes allocating all the other structs and arrays which hang off of
1267  * the context by pointers.
1268  * Note that the driver needs to pass in its dd_function_table here since
1269  * we need to at least call driverFunctions->NewTextureObject to create the
1270  * default texture objects.
1271  *
1272  * Called by _mesa_create_context().
1273  *
1274  * Performs the imports and exports callback tables initialization, and
1275  * miscellaneous one-time initializations. If no shared context is supplied one
1276  * is allocated, and increase its reference count.  Setups the GL API dispatch
1277  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
1278  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
1279  * for debug flags.
1280  *
1281  * \param ctx the context to initialize
1282  * \param visual describes the visual attributes for this context
1283  * \param share_list points to context to share textures, display lists,
1284  *        etc with, or NULL
1285  * \param driverFunctions table of device driver functions for this context
1286  *        to use
1287  * \param driverContext pointer to driver-specific context data
1288  */
1289 GLboolean
1290 _mesa_initialize_context( GLcontext *ctx,
1291                           const GLvisual *visual,
1292                           GLcontext *share_list,
1293                           const struct dd_function_table *driverFunctions,
1294                           void *driverContext )
1295 {
1296    ASSERT(driverContext);
1297    assert(driverFunctions->NewTextureObject);
1298    assert(driverFunctions->FreeTexImageData);
1299
1300    /* If the driver wants core Mesa to use special imports, it'll have to
1301     * override these defaults.
1302     */
1303    _mesa_init_default_imports( &(ctx->imports), driverContext );
1304
1305    /* initialize the exports (Mesa functions called by the window system) */
1306    _mesa_init_default_exports( &(ctx->exports) );
1307
1308    /* misc one-time initializations */
1309    one_time_init(ctx);
1310
1311    ctx->Visual = *visual;
1312    ctx->DrawBuffer = NULL;
1313    ctx->ReadBuffer = NULL;
1314    ctx->WinSysDrawBuffer = NULL;
1315    ctx->WinSysReadBuffer = NULL;
1316
1317    /* Plug in driver functions and context pointer here.
1318     * This is important because when we call alloc_shared_state() below
1319     * we'll call ctx->Driver.NewTextureObject() to create the default
1320     * textures.
1321     */
1322    ctx->Driver = *driverFunctions;
1323    ctx->DriverCtx = driverContext;
1324
1325    if (share_list) {
1326       /* share state with another context */
1327       ctx->Shared = share_list->Shared;
1328    }
1329    else {
1330       /* allocate new, unshared state */
1331       if (!alloc_shared_state( ctx )) {
1332          return GL_FALSE;
1333       }
1334    }
1335    _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1336    ctx->Shared->RefCount++;
1337    _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1338
1339    if (!init_attrib_groups( ctx )) {
1340       free_shared_state(ctx, ctx->Shared);
1341       return GL_FALSE;
1342    }
1343
1344    /* setup the API dispatch tables */
1345    ctx->Exec = alloc_dispatch_table();
1346    ctx->Save = alloc_dispatch_table();
1347    if (!ctx->Exec || !ctx->Save) {
1348       free_shared_state(ctx, ctx->Shared);
1349       if (ctx->Exec)
1350          _mesa_free(ctx->Exec);
1351    }
1352    _mesa_init_exec_table(ctx->Exec);
1353    ctx->CurrentDispatch = ctx->Exec;
1354 #if _HAVE_FULL_GL
1355    _mesa_init_dlist_table(ctx->Save);
1356    _mesa_install_save_vtxfmt( ctx, &ctx->ListState.ListVtxfmt );
1357    /* Neutral tnl module stuff */
1358    _mesa_init_exec_vtxfmt( ctx );
1359    ctx->TnlModule.Current = NULL;
1360    ctx->TnlModule.SwapCount = 0;
1361 #endif
1362
1363    ctx->VertexProgram._MaintainTnlProgram
1364       = (_mesa_getenv("MESA_TNL_PROG") != NULL);
1365    if (ctx->VertexProgram._MaintainTnlProgram)
1366       /* this is required... */
1367       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
1368    else
1369       ctx->FragmentProgram._MaintainTexEnvProgram
1370          = (_mesa_getenv("MESA_TEX_PROG") != NULL);
1371
1372    ctx->FirstTimeCurrent = GL_TRUE;
1373
1374    return GL_TRUE;
1375 }
1376
1377
1378 /**
1379  * Allocate and initialize a GLcontext structure.
1380  * Note that the driver needs to pass in its dd_function_table here since
1381  * we need to at least call driverFunctions->NewTextureObject to initialize
1382  * the rendering context.
1383  *
1384  * \param visual a GLvisual pointer (we copy the struct contents)
1385  * \param share_list another context to share display lists with or NULL
1386  * \param driverFunctions points to the dd_function_table into which the
1387  *        driver has plugged in all its special functions.
1388  * \param driverCtx points to the device driver's private context state
1389  *
1390  * \return pointer to a new __GLcontextRec or NULL if error.
1391  */
1392 GLcontext *
1393 _mesa_create_context( const GLvisual *visual,
1394                       GLcontext *share_list,
1395                       const struct dd_function_table *driverFunctions,
1396                       void *driverContext )
1397
1398 {
1399    GLcontext *ctx;
1400
1401    ASSERT(visual);
1402    ASSERT(driverContext);
1403
1404    ctx = (GLcontext *) _mesa_calloc(sizeof(GLcontext));
1405    if (!ctx)
1406       return NULL;
1407
1408    if (_mesa_initialize_context(ctx, visual, share_list,
1409                                 driverFunctions, driverContext)) {
1410       return ctx;
1411    }
1412    else {
1413       _mesa_free(ctx);
1414       return NULL;
1415    }
1416 }
1417
1418
1419 /**
1420  * Free the data associated with the given context.
1421  *
1422  * But doesn't free the GLcontext struct itself.
1423  *
1424  * \sa _mesa_initialize_context() and init_attrib_groups().
1425  */
1426 void
1427 _mesa_free_context_data( GLcontext *ctx )
1428 {
1429    /* if we're destroying the current context, unbind it first */
1430    if (ctx == _mesa_get_current_context()) {
1431       _mesa_make_current(NULL, NULL, NULL);
1432    }
1433
1434    _mesa_free_lighting_data( ctx );
1435    _mesa_free_eval_data( ctx );
1436    _mesa_free_texture_data( ctx );
1437    _mesa_free_matrix_data( ctx );
1438    _mesa_free_viewport_data( ctx );
1439    _mesa_free_colortables_data( ctx );
1440    _mesa_free_program_data(ctx);
1441    _mesa_free_query_data(ctx);
1442
1443 #if FEATURE_ARB_vertex_buffer_object
1444    _mesa_delete_buffer_object(ctx, ctx->Array.NullBufferObj);
1445 #endif
1446    _mesa_delete_array_object(ctx, ctx->Array.DefaultArrayObj);
1447
1448    /* free dispatch tables */
1449    _mesa_free(ctx->Exec);
1450    _mesa_free(ctx->Save);
1451
1452    /* Shared context state (display lists, textures, etc) */
1453    _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1454    ctx->Shared->RefCount--;
1455    assert(ctx->Shared->RefCount >= 0);
1456    _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1457    if (ctx->Shared->RefCount == 0) {
1458       /* free shared state */
1459       free_shared_state( ctx, ctx->Shared );
1460    }
1461
1462    if (ctx->Extensions.String)
1463       _mesa_free((void *) ctx->Extensions.String);
1464 }
1465
1466
1467 /**
1468  * Destroy a GLcontext structure.
1469  *
1470  * \param ctx GL context.
1471  *
1472  * Calls _mesa_free_context_data() and frees the GLcontext structure itself.
1473  */
1474 void
1475 _mesa_destroy_context( GLcontext *ctx )
1476 {
1477    if (ctx) {
1478       _mesa_free_context_data(ctx);
1479       _mesa_free( (void *) ctx );
1480    }
1481 }
1482
1483
1484 #if _HAVE_FULL_GL
1485 /**
1486  * Copy attribute groups from one context to another.
1487  *
1488  * \param src source context
1489  * \param dst destination context
1490  * \param mask bitwise OR of GL_*_BIT flags
1491  *
1492  * According to the bits specified in \p mask, copies the corresponding
1493  * attributes from \p src into \p dst.  For many of the attributes a simple \c
1494  * memcpy is not enough due to the existence of internal pointers in their data
1495  * structures.
1496  */
1497 void
1498 _mesa_copy_context( const GLcontext *src, GLcontext *dst, GLuint mask )
1499 {
1500    if (mask & GL_ACCUM_BUFFER_BIT) {
1501       /* OK to memcpy */
1502       dst->Accum = src->Accum;
1503    }
1504    if (mask & GL_COLOR_BUFFER_BIT) {
1505       /* OK to memcpy */
1506       dst->Color = src->Color;
1507    }
1508    if (mask & GL_CURRENT_BIT) {
1509       /* OK to memcpy */
1510       dst->Current = src->Current;
1511    }
1512    if (mask & GL_DEPTH_BUFFER_BIT) {
1513       /* OK to memcpy */
1514       dst->Depth = src->Depth;
1515    }
1516    if (mask & GL_ENABLE_BIT) {
1517       /* no op */
1518    }
1519    if (mask & GL_EVAL_BIT) {
1520       /* OK to memcpy */
1521       dst->Eval = src->Eval;
1522    }
1523    if (mask & GL_FOG_BIT) {
1524       /* OK to memcpy */
1525       dst->Fog = src->Fog;
1526    }
1527    if (mask & GL_HINT_BIT) {
1528       /* OK to memcpy */
1529       dst->Hint = src->Hint;
1530    }
1531    if (mask & GL_LIGHTING_BIT) {
1532       GLuint i;
1533       /* begin with memcpy */
1534       dst->Light = src->Light;
1535       /* fixup linked lists to prevent pointer insanity */
1536       make_empty_list( &(dst->Light.EnabledList) );
1537       for (i = 0; i < MAX_LIGHTS; i++) {
1538          if (dst->Light.Light[i].Enabled) {
1539             insert_at_tail(&(dst->Light.EnabledList), &(dst->Light.Light[i]));
1540          }
1541       }
1542    }
1543    if (mask & GL_LINE_BIT) {
1544       /* OK to memcpy */
1545       dst->Line = src->Line;
1546    }
1547    if (mask & GL_LIST_BIT) {
1548       /* OK to memcpy */
1549       dst->List = src->List;
1550    }
1551    if (mask & GL_PIXEL_MODE_BIT) {
1552       /* OK to memcpy */
1553       dst->Pixel = src->Pixel;
1554    }
1555    if (mask & GL_POINT_BIT) {
1556       /* OK to memcpy */
1557       dst->Point = src->Point;
1558    }
1559    if (mask & GL_POLYGON_BIT) {
1560       /* OK to memcpy */
1561       dst->Polygon = src->Polygon;
1562    }
1563    if (mask & GL_POLYGON_STIPPLE_BIT) {
1564       /* Use loop instead of MEMCPY due to problem with Portland Group's
1565        * C compiler.  Reported by John Stone.
1566        */
1567       GLuint i;
1568       for (i = 0; i < 32; i++) {
1569          dst->PolygonStipple[i] = src->PolygonStipple[i];
1570       }
1571    }
1572    if (mask & GL_SCISSOR_BIT) {
1573       /* OK to memcpy */
1574       dst->Scissor = src->Scissor;
1575    }
1576    if (mask & GL_STENCIL_BUFFER_BIT) {
1577       /* OK to memcpy */
1578       dst->Stencil = src->Stencil;
1579    }
1580    if (mask & GL_TEXTURE_BIT) {
1581       /* Cannot memcpy because of pointers */
1582       _mesa_copy_texture_state(src, dst);
1583    }
1584    if (mask & GL_TRANSFORM_BIT) {
1585       /* OK to memcpy */
1586       dst->Transform = src->Transform;
1587    }
1588    if (mask & GL_VIEWPORT_BIT) {
1589       /* Cannot use memcpy, because of pointers in GLmatrix _WindowMap */
1590       dst->Viewport.X = src->Viewport.X;
1591       dst->Viewport.Y = src->Viewport.Y;
1592       dst->Viewport.Width = src->Viewport.Width;
1593       dst->Viewport.Height = src->Viewport.Height;
1594       dst->Viewport.Near = src->Viewport.Near;
1595       dst->Viewport.Far = src->Viewport.Far;
1596       _math_matrix_copy(&dst->Viewport._WindowMap, &src->Viewport._WindowMap);
1597    }
1598
1599    /* XXX FIXME:  Call callbacks?
1600     */
1601    dst->NewState = _NEW_ALL;
1602 }
1603 #endif
1604
1605
1606 /**
1607  * Check if the given context can render into the given framebuffer
1608  * by checking visual attributes.
1609  *
1610  * XXX this may go away someday because we're moving toward more freedom
1611  * in binding contexts to drawables with different visual attributes.
1612  * The GL_EXT_f_b_o extension is prompting some of that.
1613  *
1614  * \return GL_TRUE if compatible, GL_FALSE otherwise.
1615  */
1616 static GLboolean
1617 check_compatible(const GLcontext *ctx, const GLframebuffer *buffer)
1618 {
1619    const GLvisual *ctxvis = &ctx->Visual;
1620    const GLvisual *bufvis = &buffer->Visual;
1621
1622    if (ctxvis == bufvis)
1623       return GL_TRUE;
1624
1625    if (ctxvis->rgbMode != bufvis->rgbMode)
1626       return GL_FALSE;
1627 #if 0
1628    /* disabling this fixes the fgl_glxgears pbuffer demo */
1629    if (ctxvis->doubleBufferMode && !bufvis->doubleBufferMode)
1630       return GL_FALSE;
1631 #endif
1632    if (ctxvis->stereoMode && !bufvis->stereoMode)
1633       return GL_FALSE;
1634    if (ctxvis->haveAccumBuffer && !bufvis->haveAccumBuffer)
1635       return GL_FALSE;
1636    if (ctxvis->haveDepthBuffer && !bufvis->haveDepthBuffer)
1637       return GL_FALSE;
1638    if (ctxvis->haveStencilBuffer && !bufvis->haveStencilBuffer)
1639       return GL_FALSE;
1640    if (ctxvis->redMask && ctxvis->redMask != bufvis->redMask)
1641       return GL_FALSE;
1642    if (ctxvis->greenMask && ctxvis->greenMask != bufvis->greenMask)
1643       return GL_FALSE;
1644    if (ctxvis->blueMask && ctxvis->blueMask != bufvis->blueMask)
1645       return GL_FALSE;
1646    if (ctxvis->depthBits && ctxvis->depthBits != bufvis->depthBits)
1647       return GL_FALSE;
1648    if (ctxvis->stencilBits && ctxvis->stencilBits != bufvis->stencilBits)
1649       return GL_FALSE;
1650
1651    return GL_TRUE;
1652 }
1653
1654
1655 /**
1656  * Do one-time initialization for the given framebuffer.  Specifically,
1657  * ask the driver for the window's current size and update the framebuffer
1658  * object to match.
1659  * Really, the device driver should totally take care of this.
1660  */
1661 static void
1662 initialize_framebuffer_size(GLcontext *ctx, GLframebuffer *fb)
1663 {
1664    GLuint width, height;
1665    if (ctx->Driver.GetBufferSize) {
1666       ctx->Driver.GetBufferSize(fb, &width, &height);
1667       if (ctx->Driver.ResizeBuffers)
1668          ctx->Driver.ResizeBuffers(ctx, fb, width, height);
1669       fb->Initialized = GL_TRUE;
1670    }
1671 }
1672
1673
1674 /**
1675  * Bind the given context to the given drawBuffer and readBuffer and
1676  * make it the current context for the calling thread.
1677  * We'll render into the drawBuffer and read pixels from the
1678  * readBuffer (i.e. glRead/CopyPixels, glCopyTexImage, etc).
1679  *
1680  * We check that the context's and framebuffer's visuals are compatible
1681  * and return immediately if they're not.
1682  *
1683  * \param newCtx  the new GL context. If NULL then there will be no current GL
1684  *                context.
1685  * \param drawBuffer  the drawing framebuffer
1686  * \param readBuffer  the reading framebuffer
1687  */
1688 void
1689 _mesa_make_current( GLcontext *newCtx, GLframebuffer *drawBuffer,
1690                     GLframebuffer *readBuffer )
1691 {
1692 #if 0
1693    GET_CURRENT_CONTEXT(oldCtx);
1694 #endif
1695
1696    if (MESA_VERBOSE & VERBOSE_API)
1697       _mesa_debug(newCtx, "_mesa_make_current()\n");
1698
1699    /* Check that the context's and framebuffer's visuals are compatible.
1700     */
1701    if (newCtx && drawBuffer && newCtx->WinSysDrawBuffer != drawBuffer) {
1702       if (!check_compatible(newCtx, drawBuffer)) {
1703          _mesa_warning(newCtx,
1704               "MakeCurrent: incompatible visuals for context and drawbuffer");
1705          return;
1706       }
1707    }
1708    if (newCtx && readBuffer && newCtx->WinSysReadBuffer != readBuffer) {
1709       if (!check_compatible(newCtx, readBuffer)) {
1710          _mesa_warning(newCtx,
1711               "MakeCurrent: incompatible visuals for context and readbuffer");
1712          return;
1713       }
1714    }
1715
1716 #if 0 /** XXX enable this someday */
1717    if (oldCtx && oldCtx != newCtx) {
1718       /* unbind old context's draw/read buffers */
1719       if (oldCtx->DrawBuffer && oldCtx->DrawBuffer->Name == 0) {
1720          oldCtx->DrawBuffer->RefCount--;
1721          oldCtx->DrawBuffer = NULL;
1722       }
1723       if (oldCtx->ReadBuffer && oldCtx->ReadBuffer->Name == 0) {
1724          oldCtx->ReadBuffer->RefCount--;
1725          oldCtx->ReadBuffer = NULL;
1726       }
1727       if (oldCtx->WinSysDrawBuffer) {
1728          ASSERT(oldCtx->WinSysDrawBuffer->Name == 0);
1729          oldCtx->WinSysDrawBuffer->RefCount--;
1730          oldCtx->WinSysDrawBuffer = NULL;
1731       }
1732       if (oldCtx->WinSysReadBuffer) {
1733          ASSERT(oldCtx->WinSysReadBuffer->Name == 0);
1734          oldCtx->WinSysReadBuffer->RefCount--;
1735          oldCtx->WinSysReadBuffer = NULL;
1736       }
1737    }
1738 #endif
1739
1740    /* We used to call _glapi_check_multithread() here.  Now do it in drivers */
1741    _glapi_set_context((void *) newCtx);
1742    ASSERT(_mesa_get_current_context() == newCtx);
1743
1744    if (!newCtx) {
1745       _glapi_set_dispatch(NULL);  /* none current */
1746    }
1747    else {
1748       _glapi_set_dispatch(newCtx->CurrentDispatch);
1749
1750       if (drawBuffer && readBuffer) {
1751          /* TODO: check if newCtx and buffer's visual match??? */
1752
1753          ASSERT(drawBuffer->Name == 0);
1754          ASSERT(readBuffer->Name == 0);
1755          newCtx->WinSysDrawBuffer = drawBuffer;
1756          newCtx->WinSysReadBuffer = readBuffer;
1757
1758          /*
1759           * Only set the context's Draw/ReadBuffer fields if they're NULL
1760           * or not bound to a user-created FBO.
1761           */
1762          if (!newCtx->DrawBuffer || newCtx->DrawBuffer->Name == 0) {
1763             newCtx->DrawBuffer = drawBuffer;
1764          }
1765          if (!newCtx->ReadBuffer || newCtx->ReadBuffer->Name == 0) {
1766             newCtx->ReadBuffer = readBuffer;
1767          }
1768
1769          newCtx->NewState |= _NEW_BUFFERS;
1770
1771 #if 1
1772          /* We want to get rid of these lines: */
1773
1774 #if _HAVE_FULL_GL
1775          if (!drawBuffer->Initialized) {
1776             initialize_framebuffer_size(newCtx, drawBuffer);
1777          }
1778          if (readBuffer != drawBuffer && !readBuffer->Initialized) {
1779             initialize_framebuffer_size(newCtx, readBuffer);
1780          }
1781
1782          _mesa_resizebuffers(newCtx);
1783 #endif
1784
1785 #else
1786          /* We want the drawBuffer and readBuffer to be initialized by
1787           * the driver.
1788           * This generally means the Width and Height match the actual
1789           * window size and the renderbuffers (both hardware and software
1790           * based) are allocated to match.  The later can generally be
1791           * done with a call to _mesa_resize_framebuffer().
1792           *
1793           * It's theoretically possible for a buffer to have zero width
1794           * or height, but for now, assert check that the driver did what's
1795           * expected of it.
1796           */
1797          ASSERT(drawBuffer->Width > 0);
1798          ASSERT(drawBuffer->Height > 0);
1799 #endif
1800
1801          if (newCtx->FirstTimeCurrent) {
1802             /* set initial viewport and scissor size now */
1803             _mesa_set_viewport(newCtx, 0, 0,
1804                                drawBuffer->Width, drawBuffer->Height);
1805             _mesa_set_scissor(newCtx, 0, 0,
1806                               drawBuffer->Width, drawBuffer->Height );
1807             check_context_limits(newCtx);
1808          }
1809       }
1810
1811       /* We can use this to help debug user's problems.  Tell them to set
1812        * the MESA_INFO env variable before running their app.  Then the
1813        * first time each context is made current we'll print some useful
1814        * information.
1815        */
1816       if (newCtx->FirstTimeCurrent) {
1817          if (_mesa_getenv("MESA_INFO")) {
1818             _mesa_print_info();
1819          }
1820          newCtx->FirstTimeCurrent = GL_FALSE;
1821       }
1822    }
1823 }
1824
1825
1826 /**
1827  * Make context 'ctx' share the display lists, textures and programs
1828  * that are associated with 'ctxToShare'.
1829  * Any display lists, textures or programs associated with 'ctx' will
1830  * be deleted if nobody else is sharing them.
1831  */
1832 GLboolean
1833 _mesa_share_state(GLcontext *ctx, GLcontext *ctxToShare)
1834 {
1835    if (ctx && ctxToShare && ctx->Shared && ctxToShare->Shared) {
1836       ctx->Shared->RefCount--;
1837       if (ctx->Shared->RefCount == 0) {
1838          free_shared_state(ctx, ctx->Shared);
1839       }
1840       ctx->Shared = ctxToShare->Shared;
1841       ctx->Shared->RefCount++;
1842       return GL_TRUE;
1843    }
1844    else {
1845       return GL_FALSE;
1846    }
1847 }
1848
1849
1850
1851 /**
1852  * Get current context for the calling thread.
1853  *
1854  * \return pointer to the current GL context.
1855  *
1856  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1857  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in context.h.
1858  */
1859 GLcontext *
1860 _mesa_get_current_context( void )
1861 {
1862    return (GLcontext *) _glapi_get_context();
1863 }
1864
1865 /**
1866  * Get context's current API dispatch table.
1867  *
1868  * It'll either be the immediate-mode execute dispatcher or the display list
1869  * compile dispatcher.
1870  *
1871  * \param ctx GL context.
1872  *
1873  * \return pointer to dispatch_table.
1874  *
1875  * Simply returns __GLcontextRec::CurrentDispatch.
1876  */
1877 struct _glapi_table *
1878 _mesa_get_dispatch(GLcontext *ctx)
1879 {
1880    return ctx->CurrentDispatch;
1881 }
1882
1883 /*@}*/
1884
1885
1886 /**********************************************************************/
1887 /** \name Miscellaneous functions                                     */
1888 /**********************************************************************/
1889 /*@{*/
1890
1891 /**
1892  * Record an error.
1893  *
1894  * \param ctx GL context.
1895  * \param error error code.
1896  *
1897  * Records the given error code and call the driver's dd_function_table::Error
1898  * function if defined.
1899  *
1900  * \sa
1901  * This is called via _mesa_error().
1902  */
1903 void
1904 _mesa_record_error( GLcontext *ctx, GLenum error )
1905 {
1906    if (!ctx)
1907       return;
1908
1909    if (ctx->ErrorValue == GL_NO_ERROR) {
1910       ctx->ErrorValue = error;
1911    }
1912
1913    /* Call device driver's error handler, if any.  This is used on the Mac. */
1914    if (ctx->Driver.Error) {
1915       (*ctx->Driver.Error)( ctx );
1916    }
1917 }
1918
1919 /**
1920  * Execute glFinish().
1921  *
1922  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1923  * dd_function_table::Finish driver callback, if not NULL.
1924  */
1925 void GLAPIENTRY
1926 _mesa_Finish( void )
1927 {
1928    GET_CURRENT_CONTEXT(ctx);
1929    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1930    if (ctx->Driver.Finish) {
1931       (*ctx->Driver.Finish)( ctx );
1932    }
1933 }
1934
1935 /**
1936  * Execute glFlush().
1937  *
1938  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1939  * dd_function_table::Flush driver callback, if not NULL.
1940  */
1941 void GLAPIENTRY
1942 _mesa_Flush( void )
1943 {
1944    GET_CURRENT_CONTEXT(ctx);
1945    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1946    if (ctx->Driver.Flush) {
1947       (*ctx->Driver.Flush)( ctx );
1948    }
1949 }
1950
1951
1952 /*@}*/