api_validate.c revision 88af3f8783452dcf50a9e2e82076f52b2044f643 
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, GL_ELEMENT_ARRAY_BUFFER,
48                                  GL_READ_ONLY, elementBuf);
49      /* Actual address is the sum of pointers */
50      indices = (const GLvoid *) ADD_POINTERS(map, (const GLubyte *) indices);
51   }
52
53   if (type == GL_UNSIGNED_INT) {
54      for (i = 0; i < count; i++)
55         if (((GLuint *) indices)[i] > max)
56            max = ((GLuint *) indices)[i];
57   }
58   else if (type == GL_UNSIGNED_SHORT) {
59      for (i = 0; i < count; i++)
60         if (((GLushort *) indices)[i] > max)
61            max = ((GLushort *) indices)[i];
62   }
63   else {
64      ASSERT(type == GL_UNSIGNED_BYTE);
65      for (i = 0; i < count; i++)
66         if (((GLubyte *) indices)[i] > max)
67            max = ((GLubyte *) indices)[i];
68   }
69
70   if (map) {
71      ctx->Driver.UnmapBuffer(ctx, GL_ELEMENT_ARRAY_BUFFER_ARB, elementBuf);
72   }
73
74   return max;
75}
76
77
78/**
79 * Check if OK to render by examining framebuffer status and vertex arrays.
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
108
109/**
110 * Error checking for glDrawElements().  Includes parameter checking
111 * and VBO bounds checking.
112 * \return GL_TRUE if OK to render, GL_FALSE if error found
113 */
114GLboolean
115_mesa_validate_DrawElements(GLcontext *ctx,
116			    GLenum mode, GLsizei count, GLenum type,
117			    const GLvoid *indices)
118{
119   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx,  GL_FALSE);
120
121   if (count <= 0) {
122      if (count < 0)
123	 _mesa_error(ctx, GL_INVALID_VALUE, "glDrawElements(count)" );
124      return GL_FALSE;
125   }
126
127   if (mode > GL_POLYGON) {
128      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(mode)" );
129      return GL_FALSE;
130   }
131
132   if (type != GL_UNSIGNED_INT &&
133       type != GL_UNSIGNED_BYTE &&
134       type != GL_UNSIGNED_SHORT)
135   {
136      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(type)" );
137      return GL_FALSE;
138   }
139
140   if (ctx->NewState)
141      _mesa_update_state(ctx);
142
143   if (!check_valid_to_render(ctx, "Elements"))
144      return GL_FALSE;
145
146   /* Vertex buffer object tests */
147   if (ctx->Array.ElementArrayBufferObj->Name) {
148      /* use indices in the buffer object */
149      GLuint indexBytes;
150
151      if (!ctx->Array.ElementArrayBufferObj->Size) {
152         _mesa_warning(ctx,
153                       "glDrawElements called with empty array elements buffer");
154         return GL_FALSE;
155      }
156
157      if (type == GL_UNSIGNED_INT) {
158         indexBytes = count * sizeof(GLuint);
159      }
160      else if (type == GL_UNSIGNED_BYTE) {
161         indexBytes = count * sizeof(GLubyte);
162      }
163      else {
164         ASSERT(type == GL_UNSIGNED_SHORT);
165         indexBytes = count * sizeof(GLushort);
166      }
167
168      /* make sure count doesn't go outside buffer bounds */
169      if (indexBytes > (GLuint) ctx->Array.ElementArrayBufferObj->Size) {
170         _mesa_warning(ctx, "glDrawElements index out of buffer bounds");
171         return GL_FALSE;
172      }
173   }
174   else {
175      /* not using a VBO */
176      if (!indices)
177         return GL_FALSE;
178   }
179
180   if (ctx->Const.CheckArrayBounds) {
181      /* find max array index */
182      GLuint max = max_buffer_index(ctx, count, type, indices,
183                                    ctx->Array.ElementArrayBufferObj);
184      if (max >= ctx->Array._MaxElement) {
185         /* the max element is out of bounds of one or more enabled arrays */
186         return GL_FALSE;
187      }
188   }
189
190   return GL_TRUE;
191}
192
193
194/**
195 * Error checking for glDrawRangeElements().  Includes parameter checking
196 * and VBO bounds checking.
197 * \return GL_TRUE if OK to render, GL_FALSE if error found
198 */
199GLboolean
200_mesa_validate_DrawRangeElements(GLcontext *ctx, GLenum mode,
201				 GLuint start, GLuint end,
202				 GLsizei count, GLenum type,
203				 const GLvoid *indices)
204{
205   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
206
207   if (count <= 0) {
208      if (count < 0)
209	 _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(count)" );
210      return GL_FALSE;
211   }
212
213   if (mode > GL_POLYGON) {
214      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(mode)" );
215      return GL_FALSE;
216   }
217
218   if (end < start) {
219      _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(end<start)");
220      return GL_FALSE;
221   }
222
223   if (type != GL_UNSIGNED_INT &&
224       type != GL_UNSIGNED_BYTE &&
225       type != GL_UNSIGNED_SHORT) {
226      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(type)" );
227      return GL_FALSE;
228   }
229
230   if (ctx->NewState)
231      _mesa_update_state(ctx);
232
233   if (!check_valid_to_render(ctx, "RangeElements"))
234      return GL_FALSE;
235
236   /* Vertex buffer object tests */
237   if (ctx->Array.ElementArrayBufferObj->Name) {
238      /* use indices in the buffer object */
239      GLuint indexBytes;
240
241      if (type == GL_UNSIGNED_INT) {
242         indexBytes = count * sizeof(GLuint);
243      }
244      else if (type == GL_UNSIGNED_BYTE) {
245         indexBytes = count * sizeof(GLubyte);
246      }
247      else {
248         ASSERT(type == GL_UNSIGNED_SHORT);
249         indexBytes = count * sizeof(GLushort);
250      }
251
252      /* make sure count doesn't go outside buffer bounds */
253      if (indexBytes > ctx->Array.ElementArrayBufferObj->Size) {
254         _mesa_warning(ctx, "glDrawRangeElements index out of buffer bounds");
255         return GL_FALSE;
256      }
257   }
258   else {
259      /* not using a VBO */
260      if (!indices)
261         return GL_FALSE;
262   }
263
264   if (ctx->Const.CheckArrayBounds) {
265      GLuint max = max_buffer_index(ctx, count, type, indices,
266                                    ctx->Array.ElementArrayBufferObj);
267      if (max >= ctx->Array._MaxElement) {
268         /* the max element is out of bounds of one or more enabled arrays */
269         return GL_FALSE;
270      }
271   }
272
273   return GL_TRUE;
274}
275
276
277/**
278 * Called from the tnl module to error check the function parameters and
279 * verify that we really can draw something.
280 * \return GL_TRUE if OK to render, GL_FALSE if error found
281 */
282GLboolean
283_mesa_validate_DrawArrays(GLcontext *ctx,
284			  GLenum mode, GLint start, GLsizei count)
285{
286   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
287
288   if (count <= 0) {
289      if (count < 0)
290         _mesa_error(ctx, GL_INVALID_VALUE, "glDrawArrays(count)" );
291      return GL_FALSE;
292   }
293
294   if (mode > GL_POLYGON) {
295      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawArrays(mode)" );
296      return GL_FALSE;
297   }
298
299   if (ctx->NewState)
300      _mesa_update_state(ctx);
301
302   if (!check_valid_to_render(ctx, "Arrays"))
303      return GL_FALSE;
304
305   if (ctx->Const.CheckArrayBounds) {
306      if (start + count > (GLint) ctx->Array._MaxElement)
307         return GL_FALSE;
308   }
309
310   return GL_TRUE;
311}
312