2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
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:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
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.
26 * \file glapi_getproc.c
28 * Code for implementing glXGetProcAddress(), etc.
29 * This was originally in glapi.c but refactored out.
33 #ifdef HAVE_DIX_CONFIG_H
34 #include <dix-config.h>
35 #include "glapi/mesa.h"
37 #include "main/glheader.h"
38 #include "main/compiler.h"
41 #include "glapi/glapi.h"
42 #include "glapi/glapi_priv.h"
43 #include "glapi/glapitable.h"
44 #include "glapi/glapioffsets.h"
47 /**********************************************************************
48 * Static function management.
52 #if !defined(DISPATCH_FUNCTION_SIZE) && !defined(XFree86Server)
53 # define NEED_FUNCTION_POINTER
55 #include "glapi/glprocs.h"
59 * Search the table of static entrypoint functions for the named function
60 * and return the corresponding glprocs_table_t entry.
62 static const glprocs_table_t
*
63 get_static_proc( const char * n
)
66 for (i
= 0; static_functions
[i
].Name_offset
>= 0; i
++) {
67 const char *testName
= gl_string_table
+ static_functions
[i
].Name_offset
;
69 /* skip the prefix on the name */
70 if (strcmp(testName
, n
+ 1) == 0)
72 if (strcmp(testName
, n
) == 0)
75 return &static_functions
[i
];
83 * Return dispatch table offset of the named static (built-in) function.
84 * Return -1 if function not found.
87 get_static_proc_offset(const char *funcName
)
89 const glprocs_table_t
* const f
= get_static_proc( funcName
);
98 #if !defined(XFree86Server)
101 * Return dispatch function address for the named static (built-in) function.
102 * Return NULL if function not found.
105 get_static_proc_address(const char *funcName
)
107 const glprocs_table_t
* const f
= get_static_proc( funcName
);
112 #if defined(DISPATCH_FUNCTION_SIZE) && defined(GLX_INDIRECT_RENDERING)
113 return (f
->Address
== NULL
)
114 ? get_entrypoint_address(f
->Offset
)
116 #elif defined(DISPATCH_FUNCTION_SIZE)
117 return get_entrypoint_address(f
->Offset
);
126 get_static_proc_address(const char *funcName
)
132 #endif /* !defined(XFree86Server) */
136 * Return the name of the function at the given offset in the dispatch
137 * table. For debugging only.
140 get_static_proc_name( GLuint offset
)
143 for (i
= 0; static_functions
[i
].Name_offset
>= 0; i
++) {
144 if (static_functions
[i
].Offset
== offset
) {
145 return gl_string_table
+ static_functions
[i
].Name_offset
;
153 /**********************************************************************
154 * Extension function management.
159 * Track information about a function added to the GL API.
161 struct _glapi_function
{
163 * Name of the function.
169 * Text string that describes the types of the parameters passed to the
170 * named function. Parameter types are converted to characters using the
172 * - 'i' for \c GLint, \c GLuint, and \c GLenum
173 * - 'p' for any pointer type
174 * - 'f' for \c GLfloat and \c GLclampf
175 * - 'd' for \c GLdouble and \c GLclampd
177 const char * parameter_signature
;
181 * Offset in the dispatch table where the pointer to the real function is
182 * located. If the driver has not requested that the named function be
183 * added to the dispatch table, this will have the value ~0.
185 unsigned dispatch_offset
;
189 * Pointer to the dispatch stub for the named function.
192 * The semantic of this field should be changed slightly. Currently, it
193 * is always expected to be non-\c NULL. However, it would be better to
194 * only allocate the entry-point stub when the application requests the
195 * function via \c glXGetProcAddress. This would save memory for all the
196 * functions that the driver exports but that the application never wants
199 _glapi_proc dispatch_stub
;
204 * Number of extension functions which we can dynamically add at runtime.
206 #define MAX_EXTENSION_FUNCS 300
209 static struct _glapi_function ExtEntryTable
[MAX_EXTENSION_FUNCS
];
210 static GLuint NumExtEntryPoints
= 0;
213 static struct _glapi_function
*
214 get_extension_proc(const char *funcName
)
217 for (i
= 0; i
< NumExtEntryPoints
; i
++) {
218 if (strcmp(ExtEntryTable
[i
].name
, funcName
) == 0) {
219 return & ExtEntryTable
[i
];
227 get_extension_proc_offset(const char *funcName
)
229 const struct _glapi_function
* const f
= get_extension_proc( funcName
);
234 return f
->dispatch_offset
;
239 get_extension_proc_address(const char *funcName
)
241 const struct _glapi_function
* const f
= get_extension_proc( funcName
);
246 return f
->dispatch_stub
;
251 get_extension_proc_name(GLuint offset
)
254 for (i
= 0; i
< NumExtEntryPoints
; i
++) {
255 if (ExtEntryTable
[i
].dispatch_offset
== offset
) {
256 return ExtEntryTable
[i
].name
;
264 * strdup() is actually not a standard ANSI C or POSIX routine.
265 * Irix will not define it if ANSI mode is in effect.
268 str_dup(const char *str
)
271 copy
= (char*) malloc(strlen(str
) + 1);
280 * Generate new entrypoint
282 * Use a temporary dispatch offset of ~0 (i.e. -1). Later, when the driver
283 * calls \c _glapi_add_dispatch we'll put in the proper offset. If that
284 * never happens, and the user calls this function, he'll segfault. That's
285 * what you get when you try calling a GL function that doesn't really exist.
287 * \param funcName Name of the function to create an entry-point for.
289 * \sa _glapi_add_entrypoint
292 static struct _glapi_function
*
293 add_function_name( const char * funcName
)
295 struct _glapi_function
* entry
= NULL
;
296 _glapi_proc entrypoint
= NULL
;
297 char * name_dup
= NULL
;
299 if (NumExtEntryPoints
>= MAX_EXTENSION_FUNCS
)
302 if (funcName
== NULL
)
305 name_dup
= str_dup(funcName
);
306 if (name_dup
== NULL
)
309 entrypoint
= generate_entrypoint(~0);
311 if (entrypoint
== NULL
) {
316 entry
= & ExtEntryTable
[NumExtEntryPoints
];
319 entry
->name
= name_dup
;
320 entry
->parameter_signature
= NULL
;
321 entry
->dispatch_offset
= ~0;
322 entry
->dispatch_stub
= entrypoint
;
328 static struct _glapi_function
*
329 set_entry_info( struct _glapi_function
* entry
, const char * signature
, unsigned offset
)
331 char * sig_dup
= NULL
;
333 if (signature
== NULL
)
336 sig_dup
= str_dup(signature
);
340 fill_in_entrypoint_offset(entry
->dispatch_stub
, offset
);
342 entry
->parameter_signature
= sig_dup
;
343 entry
->dispatch_offset
= offset
;
350 * Fill-in the dispatch stub for the named function.
352 * This function is intended to be called by a hardware driver. When called,
353 * a dispatch stub may be created created for the function. A pointer to this
354 * dispatch function will be returned by glXGetProcAddress.
356 * \param function_names Array of pointers to function names that should
357 * share a common dispatch offset.
358 * \param parameter_signature String representing the types of the parameters
359 * passed to the named function. Parameter types
360 * are converted to characters using the following
362 * - 'i' for \c GLint, \c GLuint, and \c GLenum
363 * - 'p' for any pointer type
364 * - 'f' for \c GLfloat and \c GLclampf
365 * - 'd' for \c GLdouble and \c GLclampd
368 * The offset in the dispatch table of the named function. A pointer to the
369 * driver's implementation of the named function should be stored at
370 * \c dispatch_table[\c offset]. Return -1 if error/problem.
372 * \sa glXGetProcAddress
375 * This function can only handle up to 8 names at a time. As far as I know,
376 * the maximum number of names ever associated with an existing GL function is
377 * 4 (\c glPointParameterfSGIS, \c glPointParameterfEXT,
378 * \c glPointParameterfARB, and \c glPointParameterf), so this should not be
379 * too painful of a limitation.
382 * Determine whether or not \c parameter_signature should be allowed to be
383 * \c NULL. It doesn't seem like much of a hardship for drivers to have to
384 * pass in an empty string.
387 * Determine if code should be added to reject function names that start with
391 * Add code to compare \c parameter_signature with the parameter signature of
392 * a static function. In order to do that, we need to find a way to \b get
393 * the parameter signature of a static function.
397 _glapi_add_dispatch( const char * const * function_names
,
398 const char * parameter_signature
)
400 static int next_dynamic_offset
= _gloffset_FIRST_DYNAMIC
;
401 const char * const real_sig
= (parameter_signature
!= NULL
)
402 ? parameter_signature
: "";
403 struct _glapi_function
* entry
[8];
404 GLboolean is_static
[8];
408 init_glapi_relocs_once();
410 (void) memset( is_static
, 0, sizeof( is_static
) );
411 (void) memset( entry
, 0, sizeof( entry
) );
413 /* Find the _single_ dispatch offset for all function names that already
414 * exist (and have a dispatch offset).
417 for ( i
= 0 ; function_names
[i
] != NULL
; i
++ ) {
418 const char * funcName
= function_names
[i
];
420 int extension_offset
;
422 if (funcName
[0] != 'g' || funcName
[1] != 'l')
425 /* search built-in functions */
426 static_offset
= get_static_proc_offset(funcName
);
428 if (static_offset
>= 0) {
430 is_static
[i
] = GL_TRUE
;
432 /* FIXME: Make sure the parameter signatures match! How do we get
433 * FIXME: the parameter signature for static functions?
436 if ( (offset
!= ~0) && (static_offset
!= offset
) ) {
440 offset
= static_offset
;
445 /* search added extension functions */
446 entry
[i
] = get_extension_proc(funcName
);
448 if (entry
[i
] != NULL
) {
449 extension_offset
= entry
[i
]->dispatch_offset
;
451 /* The offset may be ~0 if the function name was added by
452 * glXGetProcAddress but never filled in by the driver.
455 if (extension_offset
== ~0) {
459 if (strcmp(real_sig
, entry
[i
]->parameter_signature
) != 0) {
463 if ( (offset
!= ~0) && (extension_offset
!= offset
) ) {
467 offset
= extension_offset
;
471 /* If all function names are either new (or with no dispatch offset),
472 * allocate a new dispatch offset.
476 offset
= next_dynamic_offset
;
477 next_dynamic_offset
++;
480 /* Fill in the dispatch offset for the new function names (and those with
481 * no dispatch offset).
484 for ( i
= 0 ; function_names
[i
] != NULL
; i
++ ) {
489 /* generate entrypoints for new function names */
490 if (entry
[i
] == NULL
) {
491 entry
[i
] = add_function_name( function_names
[i
] );
492 if (entry
[i
] == NULL
) {
493 /* FIXME: Possible memory leak here. */
498 if (entry
[i
]->dispatch_offset
== ~0) {
499 set_entry_info( entry
[i
], real_sig
, offset
);
508 * Return offset of entrypoint for named function within dispatch table.
511 _glapi_get_proc_offset(const char *funcName
)
515 /* search extension functions first */
516 offset
= get_extension_proc_offset(funcName
);
520 /* search static functions */
521 return get_static_proc_offset(funcName
);
527 * Return pointer to the named function. If the function name isn't found
528 * in the name of static functions, try generating a new API entrypoint on
529 * the fly with assembly language.
532 _glapi_get_proc_address(const char *funcName
)
535 struct _glapi_function
* entry
;
537 init_glapi_relocs_once();
540 /* skip the prefix on the name */
541 if (funcName
[1] != 'g' || funcName
[2] != 'l')
544 if (funcName
[0] != 'g' || funcName
[1] != 'l')
548 /* search extension functions first */
549 func
= get_extension_proc_address(funcName
);
553 /* search static functions */
554 func
= get_static_proc_address(funcName
);
558 /* generate entrypoint, dispatch offset must be filled in by the driver */
559 entry
= add_function_name(funcName
);
563 return entry
->dispatch_stub
;
569 * Return the name of the function at the given dispatch offset.
570 * This is only intended for debugging.
573 _glapi_get_proc_name(GLuint offset
)
577 /* search built-in functions */
578 n
= get_static_proc_name(offset
);
583 /* search added extension functions */
584 return get_extension_proc_name(offset
);
589 /**********************************************************************
590 * GL API table functions.
595 * The dispatch table size (number of entries) is the size of the
596 * _glapi_table struct plus the number of dynamic entries we can add.
597 * The extra slots can be filled in by DRI drivers that register new extension
600 #define DISPATCH_TABLE_SIZE (sizeof(struct _glapi_table) / sizeof(void *) + MAX_EXTENSION_FUNCS)
604 * Return size of dispatch table struct as number of functions (or
608 _glapi_get_dispatch_table_size(void)
610 return DISPATCH_TABLE_SIZE
;
615 * Make sure there are no NULL pointers in the given dispatch table.
616 * Intended for debugging purposes.
619 _glapi_check_table_not_null(const struct _glapi_table
*table
)
621 #ifdef EXTRA_DEBUG /* set to DEBUG for extra DEBUG */
622 const GLuint entries
= _glapi_get_dispatch_table_size();
623 const void **tab
= (const void **) table
;
625 for (i
= 1; i
< entries
; i
++) {
635 * Do some spot checks to be sure that the dispatch table
636 * slots are assigned correctly. For debugging only.
639 _glapi_check_table(const struct _glapi_table
*table
)
641 #ifdef EXTRA_DEBUG /* set to DEBUG for extra DEBUG */
643 GLuint BeginOffset
= _glapi_get_proc_offset("glBegin");
644 char *BeginFunc
= (char*) &table
->Begin
;
645 GLuint offset
= (BeginFunc
- (char *) table
) / sizeof(void *);
646 assert(BeginOffset
== _gloffset_Begin
);
647 assert(BeginOffset
== offset
);
650 GLuint viewportOffset
= _glapi_get_proc_offset("glViewport");
651 char *viewportFunc
= (char*) &table
->Viewport
;
652 GLuint offset
= (viewportFunc
- (char *) table
) / sizeof(void *);
653 assert(viewportOffset
== _gloffset_Viewport
);
654 assert(viewportOffset
== offset
);
657 GLuint VertexPointerOffset
= _glapi_get_proc_offset("glVertexPointer");
658 char *VertexPointerFunc
= (char*) &table
->VertexPointer
;
659 GLuint offset
= (VertexPointerFunc
- (char *) table
) / sizeof(void *);
660 assert(VertexPointerOffset
== _gloffset_VertexPointer
);
661 assert(VertexPointerOffset
== offset
);
664 GLuint ResetMinMaxOffset
= _glapi_get_proc_offset("glResetMinmax");
665 char *ResetMinMaxFunc
= (char*) &table
->ResetMinmax
;
666 GLuint offset
= (ResetMinMaxFunc
- (char *) table
) / sizeof(void *);
667 assert(ResetMinMaxOffset
== _gloffset_ResetMinmax
);
668 assert(ResetMinMaxOffset
== offset
);
671 GLuint blendColorOffset
= _glapi_get_proc_offset("glBlendColor");
672 char *blendColorFunc
= (char*) &table
->BlendColor
;
673 GLuint offset
= (blendColorFunc
- (char *) table
) / sizeof(void *);
674 assert(blendColorOffset
== _gloffset_BlendColor
);
675 assert(blendColorOffset
== offset
);
678 GLuint secondaryColor3fOffset
= _glapi_get_proc_offset("glSecondaryColor3fEXT");
679 char *secondaryColor3fFunc
= (char*) &table
->SecondaryColor3fEXT
;
680 GLuint offset
= (secondaryColor3fFunc
- (char *) table
) / sizeof(void *);
681 assert(secondaryColor3fOffset
== _gloffset_SecondaryColor3fEXT
);
682 assert(secondaryColor3fOffset
== offset
);
685 GLuint pointParameterivOffset
= _glapi_get_proc_offset("glPointParameterivNV");
686 char *pointParameterivFunc
= (char*) &table
->PointParameterivNV
;
687 GLuint offset
= (pointParameterivFunc
- (char *) table
) / sizeof(void *);
688 assert(pointParameterivOffset
== _gloffset_PointParameterivNV
);
689 assert(pointParameterivOffset
== offset
);
692 GLuint setFenceOffset
= _glapi_get_proc_offset("glSetFenceNV");
693 char *setFenceFunc
= (char*) &table
->SetFenceNV
;
694 GLuint offset
= (setFenceFunc
- (char *) table
) / sizeof(void *);
695 assert(setFenceOffset
== _gloffset_SetFenceNV
);
696 assert(setFenceOffset
== offset
);