src/mesa/main/api_validate.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.1
   4  *
   5  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 #include "glheader.h"
  26 #include "api_validate.h"
  27 #include "bufferobj.h"
  28 #include "context.h"
  29 #include "imports.h"
  30 #include "mtypes.h"
  31 #include "vbo/vbo.h"
  32
  33
  34 /**
  35  * \return  number of bytes in array [count] of type.
  36  */
  37 static GLsizei
  38 index_bytes(GLenum type, GLsizei count)
  39 {
  40    if (type == GL_UNSIGNED_INT) {
  41       return count * sizeof(GLuint);
  42    }
  43    else if (type == GL_UNSIGNED_BYTE) {
  44       return count * sizeof(GLubyte);
  45    }
  46    else {
  47       ASSERT(type == GL_UNSIGNED_SHORT);
  48       return count * sizeof(GLushort);
  49    }
  50 }
  51
  52
  53 /**
  54  * Find the max index in the given element/index buffer
  55  */
  56 GLuint
  57 _mesa_max_buffer_index(GLcontext *ctx, GLuint count, GLenum type,
  58                        const void *indices,
  59                        struct gl_buffer_object *elementBuf)
  60 {
  61    const GLubyte *map = NULL;
  62    GLuint max = 0;
  63    GLuint i;
  64
  65    if (_mesa_is_bufferobj(elementBuf)) {
  66       /* elements are in a user-defined buffer object.  need to map it */
  67       map = ctx->Driver.MapBuffer(ctx, GL_ELEMENT_ARRAY_BUFFER,
  68                                   GL_READ_ONLY, elementBuf);
  69       /* Actual address is the sum of pointers */
  70       indices = (const GLvoid *) ADD_POINTERS(map, (const GLubyte *) indices);
  71    }
  72
  73    if (type == GL_UNSIGNED_INT) {
  74       for (i = 0; i < count; i++)
  75          if (((GLuint *) indices)[i] > max)
  76             max = ((GLuint *) indices)[i];
  77    }
  78    else if (type == GL_UNSIGNED_SHORT) {
  79       for (i = 0; i < count; i++)
  80          if (((GLushort *) indices)[i] > max)
  81             max = ((GLushort *) indices)[i];
  82    }
  83    else {
  84       ASSERT(type == GL_UNSIGNED_BYTE);
  85       for (i = 0; i < count; i++)
  86          if (((GLubyte *) indices)[i] > max)
  87             max = ((GLubyte *) indices)[i];
  88    }
  89
  90    if (map) {
  91       ctx->Driver.UnmapBuffer(ctx, GL_ELEMENT_ARRAY_BUFFER_ARB, elementBuf);
  92    }
  93
  94    return max;
  95 }
  96
  97
  98 /**
  99  * Check if OK to draw arrays/elements.
 100  */
 101 static GLboolean
 102 check_valid_to_render(GLcontext *ctx, const char *function)
 103 {
 104    if (!_mesa_valid_to_render(ctx, function)) {
 105       return GL_FALSE;
 106    }
 107
 108 #if FEATURE_es2_glsl
 109    /* For ES2, we can draw if any vertex array is enabled (and we should
 110     * always have a vertex program/shader).
 111     */
 112    if (ctx->Array.ArrayObj->_Enabled == 0x0 || !ctx->VertexProgram._Current)
 113       return GL_FALSE;
 114 #else
 115    /* For regular OpenGL, only draw if we have vertex positions (regardless
 116     * of whether or not we have a vertex program/shader).
 117     */
 118    if (!ctx->Array.ArrayObj->Vertex.Enabled &&
 119        !ctx->Array.ArrayObj->VertexAttrib[0].Enabled)
 120       return GL_FALSE;
 121 #endif
 122
 123    return GL_TRUE;
 124 }
 125
 126
 127 /**
 128  * Do bounds checking on array element indexes.  Check that the vertices
 129  * pointed to by the indices don't lie outside buffer object bounds.
 130  * \return GL_TRUE if OK, GL_FALSE if any indexed vertex goes is out of bounds
 131  */
 132 static GLboolean
 133 check_index_bounds(GLcontext *ctx, GLsizei count, GLenum type,
 134                    const GLvoid *indices, GLint basevertex)
 135 {
 136    struct _mesa_prim prim;
 137    struct _mesa_index_buffer ib;
 138    GLuint min, max;
 139
 140    /* Only the X Server needs to do this -- otherwise, accessing outside
 141     * array/BO bounds allows application termination.
 142     */
 143    if (!ctx->Const.CheckArrayBounds)
 144       return GL_TRUE;
 145
 146    memset(&prim, 0, sizeof(prim));
 147    prim.count = count;
 148
 149    memset(&ib, 0, sizeof(ib));
 150    ib.type = type;
 151    ib.ptr = indices;
 152    ib.obj = ctx->Array.ElementArrayBufferObj;
 153
 154    vbo_get_minmax_index(ctx, &prim, &ib, &min, &max);
 155
 156    if ((int)(min + basevertex) < 0 ||
 157        max + basevertex > ctx->Array.ArrayObj->_MaxElement) {
 158       /* the max element is out of bounds of one or more enabled arrays */
 159       _mesa_warning(ctx, "glDrawElements() index=%u is out of bounds (max=%u)",
 160                     max, ctx->Array.ArrayObj->_MaxElement);
 161       return GL_FALSE;
 162    }
 163
 164    return GL_TRUE;
 165 }
 166
 167
 168 /**
 169  * Error checking for glDrawElements().  Includes parameter checking
 170  * and VBO bounds checking.
 171  * \return GL_TRUE if OK to render, GL_FALSE if error found
 172  */
 173 GLboolean
 174 _mesa_validate_DrawElements(GLcontext *ctx,
 175                             GLenum mode, GLsizei count, GLenum type,
 176                             const GLvoid *indices, GLint basevertex)
 177 {
 178    ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx,  GL_FALSE);
 179
 180    if (count <= 0) {
 181       if (count < 0)
 182          _mesa_error(ctx, GL_INVALID_VALUE, "glDrawElements(count)" );
 183       return GL_FALSE;
 184    }
 185
 186    if (mode > GL_POLYGON) {
 187       _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(mode)" );
 188       return GL_FALSE;
 189    }
 190
 191    if (type != GL_UNSIGNED_INT &&
 192        type != GL_UNSIGNED_BYTE &&
 193        type != GL_UNSIGNED_SHORT)
 194    {
 195       _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(type)" );
 196       return GL_FALSE;
 197    }
 198
 199    if (!check_valid_to_render(ctx, "glDrawElements"))
 200       return GL_FALSE;
 201
 202    /* Vertex buffer object tests */
 203    if (_mesa_is_bufferobj(ctx->Array.ElementArrayBufferObj)) {
 204       /* use indices in the buffer object */
 205       /* make sure count doesn't go outside buffer bounds */
 206       if (index_bytes(type, count) > ctx->Array.ElementArrayBufferObj->Size) {
 207          _mesa_warning(ctx, "glDrawElements index out of buffer bounds");
 208          return GL_FALSE;
 209       }
 210    }
 211    else {
 212       /* not using a VBO */
 213       if (!indices)
 214          return GL_FALSE;
 215    }
 216
 217    if (!check_index_bounds(ctx, count, type, indices, basevertex))
 218       return GL_FALSE;
 219
 220    return GL_TRUE;
 221 }
 222
 223
 224 /**
 225  * Error checking for glDrawRangeElements().  Includes parameter checking
 226  * and VBO bounds checking.
 227  * \return GL_TRUE if OK to render, GL_FALSE if error found
 228  */
 229 GLboolean
 230 _mesa_validate_DrawRangeElements(GLcontext *ctx, GLenum mode,
 231                                  GLuint start, GLuint end,
 232                                  GLsizei count, GLenum type,
 233                                  const GLvoid *indices, GLint basevertex)
 234 {
 235    ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
 236
 237    if (count <= 0) {
 238       if (count < 0)
 239          _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(count)" );
 240       return GL_FALSE;
 241    }
 242
 243    if (mode > GL_POLYGON) {
 244       _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(mode)" );
 245       return GL_FALSE;
 246    }
 247
 248    if (end < start) {
 249       _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(end<start)");
 250       return GL_FALSE;
 251    }
 252
 253    if (type != GL_UNSIGNED_INT &&
 254        type != GL_UNSIGNED_BYTE &&
 255        type != GL_UNSIGNED_SHORT) {
 256       _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(type)" );
 257       return GL_FALSE;
 258    }
 259
 260    if (!check_valid_to_render(ctx, "glDrawRangeElements"))
 261       return GL_FALSE;
 262
 263    /* Vertex buffer object tests */
 264    if (_mesa_is_bufferobj(ctx->Array.ElementArrayBufferObj)) {
 265       /* use indices in the buffer object */
 266       /* make sure count doesn't go outside buffer bounds */
 267       if (index_bytes(type, count) > ctx->Array.ElementArrayBufferObj->Size) {
 268          _mesa_warning(ctx, "glDrawRangeElements index out of buffer bounds");
 269          return GL_FALSE;
 270       }
 271    }
 272    else {
 273       /* not using a VBO */
 274       if (!indices)
 275          return GL_FALSE;
 276    }
 277
 278    if (!check_index_bounds(ctx, count, type, indices, basevertex))
 279       return GL_FALSE;
 280
 281    return GL_TRUE;
 282 }
 283
 284
 285 /**
 286  * Called from the tnl module to error check the function parameters and
 287  * verify that we really can draw something.
 288  * \return GL_TRUE if OK to render, GL_FALSE if error found
 289  */
 290 GLboolean
 291 _mesa_validate_DrawArrays(GLcontext *ctx,
 292                           GLenum mode, GLint start, GLsizei count)
 293 {
 294    ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
 295
 296    if (count <= 0) {
 297       if (count < 0)
 298          _mesa_error(ctx, GL_INVALID_VALUE, "glDrawArrays(count)" );
 299       return GL_FALSE;
 300    }
 301
 302    if (mode > GL_POLYGON) {
 303       _mesa_error(ctx, GL_INVALID_ENUM, "glDrawArrays(mode)" );
 304       return GL_FALSE;
 305    }
 306
 307    if (!check_valid_to_render(ctx, "glDrawArrays"))
 308       return GL_FALSE;
 309
 310    if (ctx->Const.CheckArrayBounds) {
 311       if (start + count > (GLint) ctx->Array.ArrayObj->_MaxElement)
 312          return GL_FALSE;
 313    }
 314
 315    return GL_TRUE;
 316 }