src/mesa/main/api_validate.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 #include <stdbool.h>
  26 #include "glheader.h"
  27 #include "api_validate.h"
  28 #include "bufferobj.h"
  29 #include "context.h"
  30 #include "imports.h"
  31 #include "mtypes.h"
  32 #include "enums.h"
  33 #include "vbo/vbo.h"
  34 #include "transformfeedback.h"
  35 #include <stdbool.h>
  36
  37
  38 /**
  39  * \return  number of bytes in array [count] of type.
  40  */
  41 static GLsizei
  42 index_bytes(GLenum type, GLsizei count)
  43 {
  44    if (type == GL_UNSIGNED_INT) {
  45       return count * sizeof(GLuint);
  46    }
  47    else if (type == GL_UNSIGNED_BYTE) {
  48       return count * sizeof(GLubyte);
  49    }
  50    else {
  51       ASSERT(type == GL_UNSIGNED_SHORT);
  52       return count * sizeof(GLushort);
  53    }
  54 }
  55
  56
  57 /**
  58  * Find the max index in the given element/index buffer
  59  */
  60 GLuint
  61 _mesa_max_buffer_index(struct gl_context *ctx, GLuint count, GLenum type,
  62                        const void *indices,
  63                        struct gl_buffer_object *elementBuf)
  64 {
  65    const GLubyte *map = NULL;
  66    GLuint max = 0;
  67    GLuint i;
  68
  69    if (_mesa_is_bufferobj(elementBuf)) {
  70       /* elements are in a user-defined buffer object.  need to map it */
  71       map = ctx->Driver.MapBufferRange(ctx, 0, elementBuf->Size,
  72                                        GL_MAP_READ_BIT, elementBuf);
  73       /* Actual address is the sum of pointers */
  74       indices = (const GLvoid *) ADD_POINTERS(map, (const GLubyte *) indices);
  75    }
  76
  77    if (type == GL_UNSIGNED_INT) {
  78       for (i = 0; i < count; i++)
  79          if (((GLuint *) indices)[i] > max)
  80             max = ((GLuint *) indices)[i];
  81    }
  82    else if (type == GL_UNSIGNED_SHORT) {
  83       for (i = 0; i < count; i++)
  84          if (((GLushort *) indices)[i] > max)
  85             max = ((GLushort *) indices)[i];
  86    }
  87    else {
  88       ASSERT(type == GL_UNSIGNED_BYTE);
  89       for (i = 0; i < count; i++)
  90          if (((GLubyte *) indices)[i] > max)
  91             max = ((GLubyte *) indices)[i];
  92    }
  93
  94    if (map) {
  95       ctx->Driver.UnmapBuffer(ctx, elementBuf);
  96    }
  97
  98    return max;
  99 }
 100
 101
 102 /**
 103  * Check if OK to draw arrays/elements.
 104  */
 105 static GLboolean
 106 check_valid_to_render(struct gl_context *ctx, const char *function)
 107 {
 108    if (!_mesa_valid_to_render(ctx, function)) {
 109       return GL_FALSE;
 110    }
 111
 112    switch (ctx->API) {
 113    case API_OPENGLES2:
 114       /* For ES2, we can draw if any vertex array is enabled (and we
 115        * should always have a vertex program/shader). */
 116       if (ctx->Array.ArrayObj->_Enabled == 0x0 || !ctx->VertexProgram._Current)
 117          return GL_FALSE;
 118       break;
 119
 120    case API_OPENGLES:
 121       /* For OpenGL ES, only draw if we have vertex positions
 122        */
 123       if (!ctx->Array.ArrayObj->VertexAttrib[VERT_ATTRIB_POS].Enabled)
 124          return GL_FALSE;
 125       break;
 126
 127    case API_OPENGL_COMPAT:
 128    case API_OPENGL_CORE:
 129       {
 130          const struct gl_shader_program *vsProg =
 131             ctx->Shader.CurrentVertexProgram;
 132          GLboolean haveVertexShader = (vsProg && vsProg->LinkStatus);
 133          GLboolean haveVertexProgram = ctx->VertexProgram._Enabled;
 134          if (haveVertexShader || haveVertexProgram) {
 135             /* Draw regardless of whether or not we have any vertex arrays.
 136              * (Ex: could draw a point using a constant vertex pos)
 137              */
 138             return GL_TRUE;
 139          }
 140          else {
 141             /* Draw if we have vertex positions (GL_VERTEX_ARRAY or generic
 142              * array [0]).
 143              */
 144             return (ctx->Array.ArrayObj->VertexAttrib[VERT_ATTRIB_POS].Enabled ||
 145                     ctx->Array.ArrayObj->VertexAttrib[VERT_ATTRIB_GENERIC0].Enabled);
 146          }
 147       }
 148       break;
 149
 150    default:
 151       assert(!"Invalid API value in check_valid_to_render()");
 152    }
 153
 154    return GL_TRUE;
 155 }
 156
 157
 158 /**
 159  * Do bounds checking on array element indexes.  Check that the vertices
 160  * pointed to by the indices don't lie outside buffer object bounds.
 161  * \return GL_TRUE if OK, GL_FALSE if any indexed vertex goes is out of bounds
 162  */
 163 static GLboolean
 164 check_index_bounds(struct gl_context *ctx, GLsizei count, GLenum type,
 165                    const GLvoid *indices, GLint basevertex)
 166 {
 167    struct _mesa_prim prim;
 168    struct _mesa_index_buffer ib;
 169    GLuint min, max;
 170
 171    /* Only the X Server needs to do this -- otherwise, accessing outside
 172     * array/BO bounds allows application termination.
 173     */
 174    if (!ctx->Const.CheckArrayBounds)
 175       return GL_TRUE;
 176
 177    memset(&prim, 0, sizeof(prim));
 178    prim.count = count;
 179
 180    memset(&ib, 0, sizeof(ib));
 181    ib.type = type;
 182    ib.ptr = indices;
 183    ib.obj = ctx->Array.ArrayObj->ElementArrayBufferObj;
 184
 185    vbo_get_minmax_indices(ctx, &prim, &ib, &min, &max, 1);
 186
 187    if ((int)(min + basevertex) < 0 ||
 188        max + basevertex >= ctx->Array.ArrayObj->_MaxElement) {
 189       /* the max element is out of bounds of one or more enabled arrays */
 190       _mesa_warning(ctx, "glDrawElements() index=%u is out of bounds (max=%u)",
 191                     max, ctx->Array.ArrayObj->_MaxElement);
 192       return GL_FALSE;
 193    }
 194
 195    return GL_TRUE;
 196 }
 197
 198
 199 /**
 200  * Is 'mode' a valid value for glBegin(), glDrawArrays(), glDrawElements(),
 201  * etc?  The set of legal values depends on whether geometry shaders/programs
 202  * are supported.
 203  * Note: This may be called during display list compilation.
 204  */
 205 bool
 206 _mesa_is_valid_prim_mode(struct gl_context *ctx, GLenum mode)
 207 {
 208    switch (mode) {
 209    case GL_POINTS:
 210    case GL_LINES:
 211    case GL_LINE_LOOP:
 212    case GL_LINE_STRIP:
 213    case GL_TRIANGLES:
 214    case GL_TRIANGLE_STRIP:
 215    case GL_TRIANGLE_FAN:
 216       return true;
 217    case GL_QUADS:
 218    case GL_QUAD_STRIP:
 219    case GL_POLYGON:
 220       return (ctx->API == API_OPENGL_COMPAT);
 221    case GL_LINES_ADJACENCY:
 222    case GL_LINE_STRIP_ADJACENCY:
 223    case GL_TRIANGLES_ADJACENCY:
 224    case GL_TRIANGLE_STRIP_ADJACENCY:
 225       return _mesa_is_desktop_gl(ctx) && ctx->Extensions.ARB_geometry_shader4;
 226    default:
 227       return false;
 228    }
 229 }
 230
 231
 232 /**
 233  * Is 'mode' a valid value for glBegin(), glDrawArrays(), glDrawElements(),
 234  * etc?  Also, do additional checking related to transformation feedback.
 235  * Note: this function cannot be called during glNewList(GL_COMPILE) because
 236  * this code depends on current transform feedback state.
 237  */
 238 GLboolean
 239 _mesa_valid_prim_mode(struct gl_context *ctx, GLenum mode, const char *name)
 240 {
 241    bool valid_enum = _mesa_is_valid_prim_mode(ctx, mode);
 242
 243    if (!valid_enum) {
 244       _mesa_error(ctx, GL_INVALID_ENUM, "%s(mode=%x)", name, mode);
 245       return GL_FALSE;
 246    }
 247
 248    /* From the GL_EXT_transform_feedback spec:
 249     *
 250     *     "The error INVALID_OPERATION is generated if Begin, or any command
 251     *      that performs an explicit Begin, is called when:
 252     *
 253     *      * a geometry shader is not active and <mode> does not match the
 254     *        allowed begin modes for the current transform feedback state as
 255     *        given by table X.1.
 256     *
 257     *      * a geometry shader is active and the output primitive type of the
 258     *        geometry shader does not match the allowed begin modes for the
 259     *        current transform feedback state as given by table X.1.
 260     *
 261     */
 262    if (_mesa_is_xfb_active_and_unpaused(ctx)) {
 263       GLboolean pass = GL_TRUE;
 264
 265       switch (mode) {
 266       case GL_POINTS:
 267          pass = ctx->TransformFeedback.Mode == GL_POINTS;
 268          break;
 269       case GL_LINES:
 270       case GL_LINE_STRIP:
 271       case GL_LINE_LOOP:
 272          pass = ctx->TransformFeedback.Mode == GL_LINES;
 273          break;
 274       default:
 275          pass = ctx->TransformFeedback.Mode == GL_TRIANGLES;
 276          break;
 277       }
 278       if (!pass) {
 279          _mesa_error(ctx, GL_INVALID_OPERATION,
 280                      "%s(mode=%s vs transform feedback %s)",
 281                      name,
 282                      _mesa_lookup_prim_by_nr(mode),
 283                      _mesa_lookup_prim_by_nr(ctx->TransformFeedback.Mode));
 284          return GL_FALSE;
 285       }
 286    }
 287
 288    return GL_TRUE;
 289 }
 290
 291 /**
 292  * Verify that the element type is valid.
 293  *
 294  * Generates \c GL_INVALID_ENUM and returns \c false if it is not.
 295  */
 296 static bool
 297 valid_elements_type(struct gl_context *ctx, GLenum type, const char *name)
 298 {
 299    switch (type) {
 300    case GL_UNSIGNED_BYTE:
 301    case GL_UNSIGNED_SHORT:
 302    case GL_UNSIGNED_INT:
 303       return true;
 304
 305    default:
 306       _mesa_error(ctx, GL_INVALID_ENUM, "%s(type = %s)", name,
 307                   _mesa_lookup_enum_by_nr(type));
 308       return false;
 309    }
 310 }
 311
 312 /**
 313  * Error checking for glDrawElements().  Includes parameter checking
 314  * and VBO bounds checking.
 315  * \return GL_TRUE if OK to render, GL_FALSE if error found
 316  */
 317 GLboolean
 318 _mesa_validate_DrawElements(struct gl_context *ctx,
 319                             GLenum mode, GLsizei count, GLenum type,
 320                             const GLvoid *indices, GLint basevertex)
 321 {
 322    FLUSH_CURRENT(ctx, 0);
 323
 324    /* From the GLES3 specification, section 2.14.2 (Transform Feedback
 325     * Primitive Capture):
 326     *
 327     *   The error INVALID_OPERATION is also generated by DrawElements,
 328     *   DrawElementsInstanced, and DrawRangeElements while transform feedback
 329     *   is active and not paused, regardless of mode.
 330     */
 331    if (_mesa_is_gles3(ctx) && _mesa_is_xfb_active_and_unpaused(ctx)) {
 332       _mesa_error(ctx, GL_INVALID_OPERATION,
 333                   "glDrawElements(transform feedback active)");
 334       return GL_FALSE;
 335    }
 336
 337    if (count <= 0) {
 338       if (count < 0)
 339          _mesa_error(ctx, GL_INVALID_VALUE, "glDrawElements(count)" );
 340       return GL_FALSE;
 341    }
 342
 343    if (!_mesa_valid_prim_mode(ctx, mode, "glDrawElements")) {
 344       return GL_FALSE;
 345    }
 346
 347    if (!valid_elements_type(ctx, type, "glDrawElements"))
 348       return GL_FALSE;
 349
 350    if (!check_valid_to_render(ctx, "glDrawElements"))
 351       return GL_FALSE;
 352
 353    /* Vertex buffer object tests */
 354    if (_mesa_is_bufferobj(ctx->Array.ArrayObj->ElementArrayBufferObj)) {
 355       /* use indices in the buffer object */
 356       /* make sure count doesn't go outside buffer bounds */
 357       if (index_bytes(type, count) > ctx->Array.ArrayObj->ElementArrayBufferObj->Size) {
 358          _mesa_warning(ctx, "glDrawElements index out of buffer bounds");
 359          return GL_FALSE;
 360       }
 361    }
 362    else {
 363       /* not using a VBO */
 364       if (!indices)
 365          return GL_FALSE;
 366    }
 367
 368    if (!check_index_bounds(ctx, count, type, indices, basevertex))
 369       return GL_FALSE;
 370
 371    return GL_TRUE;
 372 }
 373
 374
 375 /**
 376  * Error checking for glMultiDrawElements().  Includes parameter checking
 377  * and VBO bounds checking.
 378  * \return GL_TRUE if OK to render, GL_FALSE if error found
 379  */
 380 GLboolean
 381 _mesa_validate_MultiDrawElements(struct gl_context *ctx,
 382                                  GLenum mode, const GLsizei *count,
 383                                  GLenum type, const GLvoid * const *indices,
 384                                  GLuint primcount, const GLint *basevertex)
 385 {
 386    unsigned i;
 387
 388    FLUSH_CURRENT(ctx, 0);
 389
 390    for (i = 0; i < primcount; i++) {
 391       if (count[i] <= 0) {
 392          if (count[i] < 0)
 393             _mesa_error(ctx, GL_INVALID_VALUE,
 394                         "glMultiDrawElements(count)" );
 395          return GL_FALSE;
 396       }
 397    }
 398
 399    if (!_mesa_valid_prim_mode(ctx, mode, "glMultiDrawElements")) {
 400       return GL_FALSE;
 401    }
 402
 403    if (!valid_elements_type(ctx, type, "glMultiDrawElements"))
 404       return GL_FALSE;
 405
 406    if (!check_valid_to_render(ctx, "glMultiDrawElements"))
 407       return GL_FALSE;
 408
 409    /* Vertex buffer object tests */
 410    if (_mesa_is_bufferobj(ctx->Array.ArrayObj->ElementArrayBufferObj)) {
 411       /* use indices in the buffer object */
 412       /* make sure count doesn't go outside buffer bounds */
 413       for (i = 0; i < primcount; i++) {
 414          if (index_bytes(type, count[i]) >
 415              ctx->Array.ArrayObj->ElementArrayBufferObj->Size) {
 416             _mesa_warning(ctx,
 417                           "glMultiDrawElements index out of buffer bounds");
 418             return GL_FALSE;
 419          }
 420       }
 421    }
 422    else {
 423       /* not using a VBO */
 424       for (i = 0; i < primcount; i++) {
 425          if (!indices[i])
 426             return GL_FALSE;
 427       }
 428    }
 429
 430    for (i = 0; i < primcount; i++) {
 431       if (!check_index_bounds(ctx, count[i], type, indices[i],
 432                               basevertex ? basevertex[i] : 0))
 433          return GL_FALSE;
 434    }
 435
 436    return GL_TRUE;
 437 }
 438
 439
 440 /**
 441  * Error checking for glDrawRangeElements().  Includes parameter checking
 442  * and VBO bounds checking.
 443  * \return GL_TRUE if OK to render, GL_FALSE if error found
 444  */
 445 GLboolean
 446 _mesa_validate_DrawRangeElements(struct gl_context *ctx, GLenum mode,
 447                                  GLuint start, GLuint end,
 448                                  GLsizei count, GLenum type,
 449                                  const GLvoid *indices, GLint basevertex)
 450 {
 451    FLUSH_CURRENT(ctx, 0);
 452
 453    /* From the GLES3 specification, section 2.14.2 (Transform Feedback
 454     * Primitive Capture):
 455     *
 456     *   The error INVALID_OPERATION is also generated by DrawElements,
 457     *   DrawElementsInstanced, and DrawRangeElements while transform feedback
 458     *   is active and not paused, regardless of mode.
 459     */
 460    if (_mesa_is_gles3(ctx) && _mesa_is_xfb_active_and_unpaused(ctx)) {
 461       _mesa_error(ctx, GL_INVALID_OPERATION,
 462                   "glDrawElements(transform feedback active)");
 463       return GL_FALSE;
 464    }
 465
 466    if (count <= 0) {
 467       if (count < 0)
 468          _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(count)" );
 469       return GL_FALSE;
 470    }
 471
 472    if (!_mesa_valid_prim_mode(ctx, mode, "glDrawRangeElements")) {
 473       return GL_FALSE;
 474    }
 475
 476    if (end < start) {
 477       _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(end<start)");
 478       return GL_FALSE;
 479    }
 480
 481    if (!valid_elements_type(ctx, type, "glDrawRangeElements"))
 482       return GL_FALSE;
 483
 484    if (!check_valid_to_render(ctx, "glDrawRangeElements"))
 485       return GL_FALSE;
 486
 487    /* Vertex buffer object tests */
 488    if (_mesa_is_bufferobj(ctx->Array.ArrayObj->ElementArrayBufferObj)) {
 489       /* use indices in the buffer object */
 490       /* make sure count doesn't go outside buffer bounds */
 491       if (index_bytes(type, count) > ctx->Array.ArrayObj->ElementArrayBufferObj->Size) {
 492          _mesa_warning(ctx, "glDrawRangeElements index out of buffer bounds");
 493          return GL_FALSE;
 494       }
 495    }
 496    else {
 497       /* not using a VBO */
 498       if (!indices)
 499          return GL_FALSE;
 500    }
 501
 502    if (!check_index_bounds(ctx, count, type, indices, basevertex))
 503       return GL_FALSE;
 504
 505    return GL_TRUE;
 506 }
 507
 508
 509 /**
 510  * Called from the tnl module to error check the function parameters and
 511  * verify that we really can draw something.
 512  * \return GL_TRUE if OK to render, GL_FALSE if error found
 513  */
 514 GLboolean
 515 _mesa_validate_DrawArrays(struct gl_context *ctx,
 516                           GLenum mode, GLint start, GLsizei count)
 517 {
 518    struct gl_transform_feedback_object *xfb_obj
 519       = ctx->TransformFeedback.CurrentObject;
 520    FLUSH_CURRENT(ctx, 0);
 521
 522    if (count <= 0) {
 523       if (count < 0)
 524          _mesa_error(ctx, GL_INVALID_VALUE, "glDrawArrays(count)" );
 525       return GL_FALSE;
 526    }
 527
 528    if (!_mesa_valid_prim_mode(ctx, mode, "glDrawArrays")) {
 529       return GL_FALSE;
 530    }
 531
 532    if (!check_valid_to_render(ctx, "glDrawArrays"))
 533       return GL_FALSE;
 534
 535    if (ctx->Const.CheckArrayBounds) {
 536       if (start + count > (GLint) ctx->Array.ArrayObj->_MaxElement)
 537          return GL_FALSE;
 538    }
 539
 540    /* From the GLES3 specification, section 2.14.2 (Transform Feedback
 541     * Primitive Capture):
 542     *
 543     *   The error INVALID_OPERATION is generated by DrawArrays and
 544     *   DrawArraysInstanced if recording the vertices of a primitive to the
 545     *   buffer objects being used for transform feedback purposes would result
 546     *   in either exceeding the limits of any buffer object’s size, or in
 547     *   exceeding the end position offset + size − 1, as set by
 548     *   BindBufferRange.
 549     *
 550     * This is in contrast to the behaviour of desktop GL, where the extra
 551     * primitives are silently dropped from the transform feedback buffer.
 552     */
 553    if (_mesa_is_gles3(ctx) && _mesa_is_xfb_active_and_unpaused(ctx)) {
 554       size_t prim_count = vbo_count_tessellated_primitives(mode, count, 1);
 555       if (xfb_obj->GlesRemainingPrims < prim_count) {
 556          _mesa_error(ctx, GL_INVALID_OPERATION,
 557                      "glDrawArrays(exceeds transform feedback size)");
 558          return GL_FALSE;
 559       }
 560       xfb_obj->GlesRemainingPrims -= prim_count;
 561    }
 562
 563    return GL_TRUE;
 564 }
 565
 566
 567 GLboolean
 568 _mesa_validate_DrawArraysInstanced(struct gl_context *ctx, GLenum mode, GLint first,
 569                                    GLsizei count, GLsizei numInstances)
 570 {
 571    struct gl_transform_feedback_object *xfb_obj
 572       = ctx->TransformFeedback.CurrentObject;
 573    FLUSH_CURRENT(ctx, 0);
 574
 575    if (count <= 0) {
 576       if (count < 0)
 577          _mesa_error(ctx, GL_INVALID_VALUE,
 578                      "glDrawArraysInstanced(count=%d)", count);
 579       return GL_FALSE;
 580    }
 581
 582    if (first < 0) {
 583       _mesa_error(ctx, GL_INVALID_VALUE,
 584                   "glDrawArraysInstanced(start=%d)", first);
 585       return GL_FALSE;
 586    }
 587
 588    if (!_mesa_valid_prim_mode(ctx, mode, "glDrawArraysInstanced")) {
 589       return GL_FALSE;
 590    }
 591
 592    if (numInstances <= 0) {
 593       if (numInstances < 0)
 594          _mesa_error(ctx, GL_INVALID_VALUE,
 595                      "glDrawArraysInstanced(numInstances=%d)", numInstances);
 596       return GL_FALSE;
 597    }
 598
 599    if (!check_valid_to_render(ctx, "glDrawArraysInstanced(invalid to render)"))
 600       return GL_FALSE;
 601
 602    if (ctx->Const.CheckArrayBounds) {
 603       if (first + count > (GLint) ctx->Array.ArrayObj->_MaxElement)
 604          return GL_FALSE;
 605    }
 606
 607    /* From the GLES3 specification, section 2.14.2 (Transform Feedback
 608     * Primitive Capture):
 609     *
 610     *   The error INVALID_OPERATION is generated by DrawArrays and
 611     *   DrawArraysInstanced if recording the vertices of a primitive to the
 612     *   buffer objects being used for transform feedback purposes would result
 613     *   in either exceeding the limits of any buffer object’s size, or in
 614     *   exceeding the end position offset + size − 1, as set by
 615     *   BindBufferRange.
 616     *
 617     * This is in contrast to the behaviour of desktop GL, where the extra
 618     * primitives are silently dropped from the transform feedback buffer.
 619     */
 620    if (_mesa_is_gles3(ctx) && _mesa_is_xfb_active_and_unpaused(ctx)) {
 621       size_t prim_count
 622          = vbo_count_tessellated_primitives(mode, count, numInstances);
 623       if (xfb_obj->GlesRemainingPrims < prim_count) {
 624          _mesa_error(ctx, GL_INVALID_OPERATION,
 625                      "glDrawArraysInstanced(exceeds transform feedback size)");
 626          return GL_FALSE;
 627       }
 628       xfb_obj->GlesRemainingPrims -= prim_count;
 629    }
 630
 631    return GL_TRUE;
 632 }
 633
 634
 635 GLboolean
 636 _mesa_validate_DrawElementsInstanced(struct gl_context *ctx,
 637                                      GLenum mode, GLsizei count, GLenum type,
 638                                      const GLvoid *indices, GLsizei numInstances,
 639                                      GLint basevertex)
 640 {
 641    FLUSH_CURRENT(ctx, 0);
 642
 643    /* From the GLES3 specification, section 2.14.2 (Transform Feedback
 644     * Primitive Capture):
 645     *
 646     *   The error INVALID_OPERATION is also generated by DrawElements,
 647     *   DrawElementsInstanced, and DrawRangeElements while transform feedback
 648     *   is active and not paused, regardless of mode.
 649     */
 650    if (_mesa_is_gles3(ctx) && _mesa_is_xfb_active_and_unpaused(ctx)) {
 651       _mesa_error(ctx, GL_INVALID_OPERATION,
 652                   "glDrawElements(transform feedback active)");
 653       return GL_FALSE;
 654    }
 655
 656    if (count <= 0) {
 657       if (count < 0)
 658          _mesa_error(ctx, GL_INVALID_VALUE,
 659                      "glDrawElementsInstanced(count=%d)", count);
 660       return GL_FALSE;
 661    }
 662
 663    if (!_mesa_valid_prim_mode(ctx, mode, "glDrawElementsInstanced")) {
 664       return GL_FALSE;
 665    }
 666
 667    if (!valid_elements_type(ctx, type, "glDrawElementsInstanced"))
 668       return GL_FALSE;
 669
 670    if (numInstances <= 0) {
 671       if (numInstances < 0)
 672          _mesa_error(ctx, GL_INVALID_VALUE,
 673                      "glDrawElementsInstanced(numInstances=%d)", numInstances);
 674       return GL_FALSE;
 675    }
 676
 677    if (!check_valid_to_render(ctx, "glDrawElementsInstanced"))
 678       return GL_FALSE;
 679
 680    /* Vertex buffer object tests */
 681    if (_mesa_is_bufferobj(ctx->Array.ArrayObj->ElementArrayBufferObj)) {
 682       /* use indices in the buffer object */
 683       /* make sure count doesn't go outside buffer bounds */
 684       if (index_bytes(type, count) > ctx->Array.ArrayObj->ElementArrayBufferObj->Size) {
 685          _mesa_warning(ctx,
 686                        "glDrawElementsInstanced index out of buffer bounds");
 687          return GL_FALSE;
 688       }
 689    }
 690    else {
 691       /* not using a VBO */
 692       if (!indices)
 693          return GL_FALSE;
 694    }
 695
 696    if (!check_index_bounds(ctx, count, type, indices, basevertex))
 697       return GL_FALSE;
 698
 699    return GL_TRUE;
 700 }
 701
 702
 703 GLboolean
 704 _mesa_validate_DrawTransformFeedback(struct gl_context *ctx,
 705                                      GLenum mode,
 706                                      struct gl_transform_feedback_object *obj,
 707                                      GLuint stream,
 708                                      GLsizei numInstances)
 709 {
 710    FLUSH_CURRENT(ctx, 0);
 711
 712    if (!_mesa_valid_prim_mode(ctx, mode, "glDrawTransformFeedback*(mode)")) {
 713       return GL_FALSE;
 714    }
 715
 716    if (!obj) {
 717       _mesa_error(ctx, GL_INVALID_VALUE, "glDrawTransformFeedback*(name)");
 718       return GL_FALSE;
 719    }
 720
 721    if (!obj->EndedAnytime) {
 722       _mesa_error(ctx, GL_INVALID_OPERATION, "glDrawTransformFeedback*");
 723       return GL_FALSE;
 724    }
 725
 726    if (stream >= ctx->Const.MaxVertexStreams) {
 727       _mesa_error(ctx, GL_INVALID_VALUE,
 728                   "glDrawTransformFeedbackStream*(index>=MaxVertexStream)");
 729       return GL_FALSE;
 730    }
 731
 732    if (numInstances <= 0) {
 733       if (numInstances < 0)
 734          _mesa_error(ctx, GL_INVALID_VALUE,
 735                      "glDrawTransformFeedback*Instanced(numInstances=%d)",
 736                      numInstances);
 737       return GL_FALSE;
 738    }
 739
 740    if (!check_valid_to_render(ctx, "glDrawTransformFeedback*")) {
 741       return GL_FALSE;
 742    }
 743
 744    return GL_TRUE;
 745 }