api_validate.c revision 37ece4df7c654b30b6720044b35a83694d7e5bb3 
1/*
2 * Mesa 3-D graphics library
3 * Version:  7.0.1
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 "context.h"
28#include "imports.h"
29#include "mtypes.h"
30#include "state.h"
31
32
33GLboolean
34_mesa_validate_DrawElements(GLcontext *ctx,
35			    GLenum mode, GLsizei count, GLenum type,
36			    const GLvoid *indices)
37{
38   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx,  GL_FALSE);
39
40   if (count <= 0) {
41      if (count < 0)
42	 _mesa_error(ctx, GL_INVALID_VALUE, "glDrawElements(count)" );
43      return GL_FALSE;
44   }
45
46   if (mode > GL_POLYGON) {
47      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(mode)" );
48      return GL_FALSE;
49   }
50
51   if (type != GL_UNSIGNED_INT &&
52       type != GL_UNSIGNED_BYTE &&
53       type != GL_UNSIGNED_SHORT)
54   {
55      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(type)" );
56      return GL_FALSE;
57   }
58
59   if (ctx->NewState)
60      _mesa_update_state(ctx);
61
62   /* Always need vertex positions */
63   if (!ctx->Array.ArrayObj->Vertex.Enabled
64       && !(ctx->VertexProgram._Enabled && ctx->Array.ArrayObj->VertexAttrib[0].Enabled))
65      return GL_FALSE;
66
67   /* Vertex buffer object tests */
68   if (ctx->Array.ElementArrayBufferObj->Name) {
69      GLuint indexBytes;
70
71      /* use indices in the buffer object */
72      if (!ctx->Array.ElementArrayBufferObj->Data) {
73         _mesa_warning(ctx, "DrawElements with empty vertex elements buffer!");
74         return GL_FALSE;
75      }
76
77      /* make sure count doesn't go outside buffer bounds */
78      if (type == GL_UNSIGNED_INT) {
79         indexBytes = count * sizeof(GLuint);
80      }
81      else if (type == GL_UNSIGNED_BYTE) {
82         indexBytes = count * sizeof(GLubyte);
83      }
84      else {
85         ASSERT(type == GL_UNSIGNED_SHORT);
86         indexBytes = count * sizeof(GLushort);
87      }
88
89      if ((GLubyte *) indices + indexBytes >
90          ctx->Array.ElementArrayBufferObj->Data +
91          ctx->Array.ElementArrayBufferObj->Size) {
92         _mesa_warning(ctx, "glDrawElements index out of buffer bounds");
93         return GL_FALSE;
94      }
95
96      /* Actual address is the sum of pointers.  Indices may be used below. */
97      if (ctx->Const.CheckArrayBounds) {
98         indices = (const GLvoid *)
99            ADD_POINTERS(ctx->Array.ElementArrayBufferObj->Data,
100                         (const GLubyte *) indices);
101      }
102   }
103   else {
104      /* not using a VBO */
105      if (!indices)
106         return GL_FALSE;
107   }
108
109   if (ctx->Const.CheckArrayBounds) {
110      /* find max array index */
111      GLuint max = 0;
112      GLint i;
113      if (type == GL_UNSIGNED_INT) {
114         for (i = 0; i < count; i++)
115            if (((GLuint *) indices)[i] > max)
116               max = ((GLuint *) indices)[i];
117      }
118      else if (type == GL_UNSIGNED_SHORT) {
119         for (i = 0; i < count; i++)
120            if (((GLushort *) indices)[i] > max)
121               max = ((GLushort *) indices)[i];
122      }
123      else {
124         ASSERT(type == GL_UNSIGNED_BYTE);
125         for (i = 0; i < count; i++)
126            if (((GLubyte *) indices)[i] > max)
127               max = ((GLubyte *) indices)[i];
128      }
129      if (max >= ctx->Array._MaxElement) {
130         /* the max element is out of bounds of one or more enabled arrays */
131         return GL_FALSE;
132      }
133   }
134
135   return GL_TRUE;
136}
137
138
139GLboolean
140_mesa_validate_DrawRangeElements(GLcontext *ctx, GLenum mode,
141				 GLuint start, GLuint end,
142				 GLsizei count, GLenum type,
143				 const GLvoid *indices)
144{
145   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
146
147   if (count <= 0) {
148      if (count < 0)
149	 _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(count)" );
150      return GL_FALSE;
151   }
152
153   if (mode > GL_POLYGON) {
154      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(mode)" );
155      return GL_FALSE;
156   }
157
158   if (end < start) {
159      _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(end<start)");
160      return GL_FALSE;
161   }
162
163   if (type != GL_UNSIGNED_INT &&
164       type != GL_UNSIGNED_BYTE &&
165       type != GL_UNSIGNED_SHORT) {
166      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(type)" );
167      return GL_FALSE;
168   }
169
170   if (ctx->NewState)
171      _mesa_update_state(ctx);
172
173   /* Always need vertex positions */
174   if (!ctx->Array.ArrayObj->Vertex.Enabled
175       && !(ctx->VertexProgram._Enabled && ctx->Array.ArrayObj->VertexAttrib[0].Enabled))
176      return GL_FALSE;
177
178   /* Vertex buffer object tests */
179   if (ctx->Array.ElementArrayBufferObj->Name) {
180      /* XXX re-use code from above? */
181   }
182   else {
183      /* not using VBO */
184      if (!indices)
185         return GL_FALSE;
186   }
187
188   if (ctx->Const.CheckArrayBounds) {
189      /* Find max array index.
190       * We don't trust the user's start and end values.
191       */
192      GLuint max = 0;
193      GLint i;
194      if (type == GL_UNSIGNED_INT) {
195         for (i = 0; i < count; i++)
196            if (((GLuint *) indices)[i] > max)
197               max = ((GLuint *) indices)[i];
198      }
199      else if (type == GL_UNSIGNED_SHORT) {
200         for (i = 0; i < count; i++)
201            if (((GLushort *) indices)[i] > max)
202               max = ((GLushort *) indices)[i];
203      }
204      else {
205         ASSERT(type == GL_UNSIGNED_BYTE);
206         for (i = 0; i < count; i++)
207            if (((GLubyte *) indices)[i] > max)
208               max = ((GLubyte *) indices)[i];
209      }
210      if (max >= ctx->Array._MaxElement) {
211         /* the max element is out of bounds of one or more enabled arrays */
212         return GL_FALSE;
213      }
214   }
215
216   return GL_TRUE;
217}
218
219
220/**
221 * Called from the tnl module to error check the function parameters and
222 * verify that we really can draw something.
223 */
224GLboolean
225_mesa_validate_DrawArrays(GLcontext *ctx,
226			  GLenum mode, GLint start, GLsizei count)
227{
228   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
229
230   if (count < 0) {
231      _mesa_error(ctx, GL_INVALID_VALUE, "glDrawArrays(count)" );
232      return GL_FALSE;
233   }
234
235   if (mode > GL_POLYGON) {
236      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawArrays(mode)" );
237      return GL_FALSE;
238   }
239
240   if (ctx->NewState)
241      _mesa_update_state(ctx);
242
243   /* Always need vertex positions */
244   if (!ctx->Array.ArrayObj->Vertex.Enabled && !ctx->Array.ArrayObj->VertexAttrib[0].Enabled)
245      return GL_FALSE;
246
247   if (ctx->Const.CheckArrayBounds) {
248      if (start + count > (GLint) ctx->Array._MaxElement)
249         return GL_FALSE;
250   }
251
252   return GL_TRUE;
253}
254