api_validate.c revision 97dd2ddbd97ba95e8bc8ab572ec05e8081556e1e 
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 "context.h"
28#include "imports.h"
29#include "mtypes.h"
30#include "state.h"
31
32
33/**
34 * Find the max index in the given element/index buffer
35 */
36static GLuint
37max_buffer_index(GLcontext *ctx, GLuint count, GLenum type,
38                 const void *indices,
39                 struct gl_buffer_object *elementBuf)
40{
41   const GLubyte *map = NULL;
42   GLuint max = 0;
43   GLint i;
44
45   if (elementBuf->Name) {
46      /* elements are in a user-defined buffer object.  need to map it */
47      map = ctx->Driver.MapBuffer(ctx,
48                                  GL_ELEMENT_ARRAY_BUFFER_ARB,
49                                  GL_READ_ONLY,
50                                  elementBuf);
51      /* Actual address is the sum of pointers */
52      indices = (const GLvoid *) ADD_POINTERS(map, (const GLubyte *) indices);
53   }
54
55   if (type == GL_UNSIGNED_INT) {
56      for (i = 0; i < count; i++)
57         if (((GLuint *) indices)[i] > max)
58            max = ((GLuint *) indices)[i];
59   }
60   else if (type == GL_UNSIGNED_SHORT) {
61      for (i = 0; i < count; i++)
62         if (((GLushort *) indices)[i] > max)
63            max = ((GLushort *) indices)[i];
64   }
65   else {
66      ASSERT(type == GL_UNSIGNED_BYTE);
67      for (i = 0; i < count; i++)
68         if (((GLubyte *) indices)[i] > max)
69            max = ((GLubyte *) indices)[i];
70   }
71
72   if (map) {
73      ctx->Driver.UnmapBuffer(ctx,
74                              GL_ELEMENT_ARRAY_BUFFER_ARB,
75                              ctx->Array.ElementArrayBufferObj);
76   }
77
78   return max;
79}
80
81static GLboolean
82check_valid_to_render(GLcontext *ctx, char *function)
83{
84   if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
85      _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
86                  "glDraw%s(incomplete framebuffer)", function);
87      return GL_FALSE;
88   }
89
90#if FEATURE_es2_glsl
91   /* For ES2, we can draw if any vertex array is enabled (and we should
92    * always have a vertex program/shader).
93    */
94   if (ctx->Array.ArrayObj->_Enabled == 0x0 || !ctx->VertexProgram._Current)
95      return GL_FALSE;
96#else
97   /* For regular OpenGL, only draw if we have vertex positions (regardless
98    * of whether or not we have a vertex program/shader).
99    */
100   if (!ctx->Array.ArrayObj->Vertex.Enabled &&
101       !ctx->Array.ArrayObj->VertexAttrib[0].Enabled)
102      return GL_FALSE;
103#endif
104
105   return GL_TRUE;
106}
107
108GLboolean
109_mesa_validate_DrawElements(GLcontext *ctx,
110			    GLenum mode, GLsizei count, GLenum type,
111			    const GLvoid *indices)
112{
113   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx,  GL_FALSE);
114
115   if (count <= 0) {
116      if (count < 0)
117	 _mesa_error(ctx, GL_INVALID_VALUE, "glDrawElements(count)" );
118      return GL_FALSE;
119   }
120
121   if (mode > GL_POLYGON) {
122      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(mode)" );
123      return GL_FALSE;
124   }
125
126   if (type != GL_UNSIGNED_INT &&
127       type != GL_UNSIGNED_BYTE &&
128       type != GL_UNSIGNED_SHORT)
129   {
130      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(type)" );
131      return GL_FALSE;
132   }
133
134   if (ctx->NewState)
135      _mesa_update_state(ctx);
136
137   if (!check_valid_to_render(ctx, "Elements"))
138      return GL_FALSE;
139
140   /* Vertex buffer object tests */
141   if (ctx->Array.ElementArrayBufferObj->Name) {
142      /* use indices in the buffer object */
143      GLuint indexBytes;
144
145      if (!ctx->Array.ElementArrayBufferObj->Size) {
146         _mesa_warning(ctx,
147                       "glDrawElements called with empty array elements buffer");
148         return GL_FALSE;
149      }
150
151      if (type == GL_UNSIGNED_INT) {
152         indexBytes = count * sizeof(GLuint);
153      }
154      else if (type == GL_UNSIGNED_BYTE) {
155         indexBytes = count * sizeof(GLubyte);
156      }
157      else {
158         ASSERT(type == GL_UNSIGNED_SHORT);
159         indexBytes = count * sizeof(GLushort);
160      }
161
162      /* make sure count doesn't go outside buffer bounds */
163      if (indexBytes > (GLuint) ctx->Array.ElementArrayBufferObj->Size) {
164         _mesa_warning(ctx, "glDrawElements index out of buffer bounds");
165         return GL_FALSE;
166      }
167   }
168   else {
169      /* not using a VBO */
170      if (!indices)
171         return GL_FALSE;
172   }
173
174   if (ctx->Const.CheckArrayBounds) {
175      /* find max array index */
176      GLuint max = max_buffer_index(ctx, count, type, indices,
177                                    ctx->Array.ElementArrayBufferObj);
178      if (max >= ctx->Array._MaxElement) {
179         /* the max element is out of bounds of one or more enabled arrays */
180         return GL_FALSE;
181      }
182   }
183
184   return GL_TRUE;
185}
186
187GLboolean
188_mesa_validate_DrawRangeElements(GLcontext *ctx, GLenum mode,
189				 GLuint start, GLuint end,
190				 GLsizei count, GLenum type,
191				 const GLvoid *indices)
192{
193   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
194
195   if (count <= 0) {
196      if (count < 0)
197	 _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(count)" );
198      return GL_FALSE;
199   }
200
201   if (mode > GL_POLYGON) {
202      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(mode)" );
203      return GL_FALSE;
204   }
205
206   if (end < start) {
207      _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(end<start)");
208      return GL_FALSE;
209   }
210
211   if (type != GL_UNSIGNED_INT &&
212       type != GL_UNSIGNED_BYTE &&
213       type != GL_UNSIGNED_SHORT) {
214      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(type)" );
215      return GL_FALSE;
216   }
217
218   if (ctx->NewState)
219      _mesa_update_state(ctx);
220
221   if (!check_valid_to_render(ctx, "RangeElements"))
222      return GL_FALSE;
223
224   /* Vertex buffer object tests */
225   if (ctx->Array.ElementArrayBufferObj->Name) {
226      /* use indices in the buffer object */
227      GLuint indexBytes;
228
229      if (type == GL_UNSIGNED_INT) {
230         indexBytes = count * sizeof(GLuint);
231      }
232      else if (type == GL_UNSIGNED_BYTE) {
233         indexBytes = count * sizeof(GLubyte);
234      }
235      else {
236         ASSERT(type == GL_UNSIGNED_SHORT);
237         indexBytes = count * sizeof(GLushort);
238      }
239
240      /* make sure count doesn't go outside buffer bounds */
241      if (indexBytes > ctx->Array.ElementArrayBufferObj->Size) {
242         _mesa_warning(ctx, "glDrawRangeElements index out of buffer bounds");
243         return GL_FALSE;
244      }
245   }
246   else {
247      /* not using a VBO */
248      if (!indices)
249         return GL_FALSE;
250   }
251
252   if (ctx->Const.CheckArrayBounds) {
253      GLuint max = max_buffer_index(ctx, count, type, indices,
254                                    ctx->Array.ElementArrayBufferObj);
255      if (max >= ctx->Array._MaxElement) {
256         /* the max element is out of bounds of one or more enabled arrays */
257         return GL_FALSE;
258      }
259   }
260
261   return GL_TRUE;
262}
263
264
265/**
266 * Called from the tnl module to error check the function parameters and
267 * verify that we really can draw something.
268 */
269GLboolean
270_mesa_validate_DrawArrays(GLcontext *ctx,
271			  GLenum mode, GLint start, GLsizei count)
272{
273   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
274
275   if (count <= 0) {
276      if (count < 0)
277         _mesa_error(ctx, GL_INVALID_VALUE, "glDrawArrays(count)" );
278      return GL_FALSE;
279   }
280
281   if (mode > GL_POLYGON) {
282      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawArrays(mode)" );
283      return GL_FALSE;
284   }
285
286   if (ctx->NewState)
287      _mesa_update_state(ctx);
288
289   if (!check_valid_to_render(ctx, "Arrays"))
290      return GL_FALSE;
291
292   if (ctx->Const.CheckArrayBounds) {
293      if (start + count > (GLint) ctx->Array._MaxElement)
294         return GL_FALSE;
295   }
296
297   return GL_TRUE;
298}
299