| /* |
| * Mesa 3-D graphics library |
| * |
| * Copyright (C) 1999-2008 Brian Paul All Rights Reserved. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included |
| * in all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
| * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR |
| * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
| * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
| * OTHER DEALINGS IN THE SOFTWARE. |
| */ |
| |
| /** |
| * \file glapi_getproc.c |
| * |
| * Code for implementing glXGetProcAddress(), etc. |
| * This was originally in glapi.c but refactored out. |
| */ |
| |
| |
| #include <assert.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include "glapi/glapi_priv.h" |
| #include "glapitable.h" |
| |
| |
| #define FIRST_DYNAMIC_OFFSET (sizeof(struct _glapi_table) / sizeof(void *)) |
| |
| |
| |
| /********************************************************************** |
| * Static function management. |
| */ |
| |
| |
| #if !defined(DISPATCH_FUNCTION_SIZE) |
| # define NEED_FUNCTION_POINTER |
| #endif |
| #include "glprocs.h" |
| |
| |
| /** |
| * Search the table of static entrypoint functions for the named function |
| * and return the corresponding glprocs_table_t entry. |
| */ |
| static const glprocs_table_t * |
| get_static_proc( const char * n ) |
| { |
| GLuint i; |
| for (i = 0; static_functions[i].Name_offset >= 0; i++) { |
| const char *testName = gl_string_table + static_functions[i].Name_offset; |
| if (strcmp(testName, n) == 0) |
| { |
| return &static_functions[i]; |
| } |
| } |
| return NULL; |
| } |
| |
| |
| /** |
| * Return dispatch table offset of the named static (built-in) function. |
| * Return -1 if function not found. |
| */ |
| static GLint |
| get_static_proc_offset(const char *funcName) |
| { |
| const glprocs_table_t * const f = get_static_proc( funcName ); |
| if (f == NULL) { |
| return -1; |
| } |
| |
| return f->Offset; |
| } |
| |
| |
| |
| /** |
| * Return dispatch function address for the named static (built-in) function. |
| * Return NULL if function not found. |
| */ |
| static _glapi_proc |
| get_static_proc_address(const char *funcName) |
| { |
| const glprocs_table_t * const f = get_static_proc( funcName ); |
| if (f == NULL) { |
| return NULL; |
| } |
| |
| #if defined(DISPATCH_FUNCTION_SIZE) && defined(GLX_INDIRECT_RENDERING) |
| return (f->Address == NULL) |
| ? get_entrypoint_address(f->Offset) |
| : f->Address; |
| #elif defined(DISPATCH_FUNCTION_SIZE) |
| return get_entrypoint_address(f->Offset); |
| #else |
| return f->Address; |
| #endif |
| } |
| |
| |
| |
| /** |
| * Return the name of the function at the given offset in the dispatch |
| * table. For debugging only. |
| */ |
| static const char * |
| get_static_proc_name( GLuint offset ) |
| { |
| GLuint i; |
| for (i = 0; static_functions[i].Name_offset >= 0; i++) { |
| if (static_functions[i].Offset == offset) { |
| return gl_string_table + static_functions[i].Name_offset; |
| } |
| } |
| return NULL; |
| } |
| |
| |
| |
| /********************************************************************** |
| * Extension function management. |
| */ |
| |
| |
| /** |
| * Track information about a function added to the GL API. |
| */ |
| struct _glapi_function { |
| /** |
| * Name of the function. |
| */ |
| const char * name; |
| |
| |
| /** |
| * Text string that describes the types of the parameters passed to the |
| * named function. Parameter types are converted to characters using the |
| * following rules: |
| * - 'i' for \c GLint, \c GLuint, and \c GLenum |
| * - 'p' for any pointer type |
| * - 'f' for \c GLfloat and \c GLclampf |
| * - 'd' for \c GLdouble and \c GLclampd |
| */ |
| const char * parameter_signature; |
| |
| |
| /** |
| * Offset in the dispatch table where the pointer to the real function is |
| * located. If the driver has not requested that the named function be |
| * added to the dispatch table, this will have the value ~0. |
| */ |
| unsigned dispatch_offset; |
| |
| |
| /** |
| * Pointer to the dispatch stub for the named function. |
| * |
| * \todo |
| * The semantic of this field should be changed slightly. Currently, it |
| * is always expected to be non-\c NULL. However, it would be better to |
| * only allocate the entry-point stub when the application requests the |
| * function via \c glXGetProcAddress. This would save memory for all the |
| * functions that the driver exports but that the application never wants |
| * to call. |
| */ |
| _glapi_proc dispatch_stub; |
| }; |
| |
| |
| static struct _glapi_function ExtEntryTable[MAX_EXTENSION_FUNCS]; |
| static GLuint NumExtEntryPoints = 0; |
| |
| |
| static struct _glapi_function * |
| get_extension_proc(const char *funcName) |
| { |
| GLuint i; |
| for (i = 0; i < NumExtEntryPoints; i++) { |
| if (strcmp(ExtEntryTable[i].name, funcName) == 0) { |
| return & ExtEntryTable[i]; |
| } |
| } |
| return NULL; |
| } |
| |
| |
| static GLint |
| get_extension_proc_offset(const char *funcName) |
| { |
| const struct _glapi_function * const f = get_extension_proc( funcName ); |
| if (f == NULL) { |
| return -1; |
| } |
| |
| return f->dispatch_offset; |
| } |
| |
| |
| static _glapi_proc |
| get_extension_proc_address(const char *funcName) |
| { |
| const struct _glapi_function * const f = get_extension_proc( funcName ); |
| if (f == NULL) { |
| return NULL; |
| } |
| |
| return f->dispatch_stub; |
| } |
| |
| |
| static const char * |
| get_extension_proc_name(GLuint offset) |
| { |
| GLuint i; |
| for (i = 0; i < NumExtEntryPoints; i++) { |
| if (ExtEntryTable[i].dispatch_offset == offset) { |
| return ExtEntryTable[i].name; |
| } |
| } |
| return NULL; |
| } |
| |
| |
| /** |
| * strdup() is actually not a standard ANSI C or POSIX routine. |
| * Irix will not define it if ANSI mode is in effect. |
| */ |
| static char * |
| str_dup(const char *str) |
| { |
| char *copy; |
| copy = malloc(strlen(str) + 1); |
| if (!copy) |
| return NULL; |
| strcpy(copy, str); |
| return copy; |
| } |
| |
| |
| /** |
| * Generate new entrypoint |
| * |
| * Use a temporary dispatch offset of ~0 (i.e. -1). Later, when the driver |
| * calls \c _glapi_add_dispatch we'll put in the proper offset. If that |
| * never happens, and the user calls this function, he'll segfault. That's |
| * what you get when you try calling a GL function that doesn't really exist. |
| * |
| * \param funcName Name of the function to create an entry-point for. |
| * |
| * \sa _glapi_add_entrypoint |
| */ |
| |
| static struct _glapi_function * |
| add_function_name( const char * funcName ) |
| { |
| struct _glapi_function * entry = NULL; |
| _glapi_proc entrypoint = NULL; |
| char * name_dup = NULL; |
| |
| if (NumExtEntryPoints >= MAX_EXTENSION_FUNCS) |
| return NULL; |
| |
| if (funcName == NULL) |
| return NULL; |
| |
| name_dup = str_dup(funcName); |
| if (name_dup == NULL) |
| return NULL; |
| |
| entrypoint = generate_entrypoint(~0); |
| |
| if (entrypoint == NULL) { |
| free(name_dup); |
| return NULL; |
| } |
| |
| entry = & ExtEntryTable[NumExtEntryPoints]; |
| NumExtEntryPoints++; |
| |
| entry->name = name_dup; |
| entry->parameter_signature = NULL; |
| entry->dispatch_offset = ~0; |
| entry->dispatch_stub = entrypoint; |
| |
| return entry; |
| } |
| |
| |
| static struct _glapi_function * |
| set_entry_info( struct _glapi_function * entry, const char * signature, unsigned offset ) |
| { |
| char * sig_dup = NULL; |
| |
| if (signature == NULL) |
| return NULL; |
| |
| sig_dup = str_dup(signature); |
| if (sig_dup == NULL) |
| return NULL; |
| |
| fill_in_entrypoint_offset(entry->dispatch_stub, offset); |
| |
| entry->parameter_signature = sig_dup; |
| entry->dispatch_offset = offset; |
| |
| return entry; |
| } |
| |
| |
| /** |
| * Fill-in the dispatch stub for the named function. |
| * |
| * This function is intended to be called by a hardware driver. When called, |
| * a dispatch stub may be created for the function. A pointer to this |
| * dispatch function will be returned by glXGetProcAddress. |
| * |
| * \param function_names Array of pointers to function names that should |
| * share a common dispatch offset. |
| * \param parameter_signature String representing the types of the parameters |
| * passed to the named function. Parameter types |
| * are converted to characters using the following |
| * rules: |
| * - 'i' for \c GLint, \c GLuint, and \c GLenum |
| * - 'p' for any pointer type |
| * - 'f' for \c GLfloat and \c GLclampf |
| * - 'd' for \c GLdouble and \c GLclampd |
| * |
| * \returns |
| * The offset in the dispatch table of the named function. A pointer to the |
| * driver's implementation of the named function should be stored at |
| * \c dispatch_table[\c offset]. Return -1 if error/problem. |
| * |
| * \sa glXGetProcAddress |
| * |
| * \warning |
| * This function can only handle up to 8 names at a time. As far as I know, |
| * the maximum number of names ever associated with an existing GL function is |
| * 4 (\c glPointParameterfSGIS, \c glPointParameterfEXT, |
| * \c glPointParameterfARB, and \c glPointParameterf), so this should not be |
| * too painful of a limitation. |
| * |
| * \todo |
| * Determine whether or not \c parameter_signature should be allowed to be |
| * \c NULL. It doesn't seem like much of a hardship for drivers to have to |
| * pass in an empty string. |
| * |
| * \todo |
| * Determine if code should be added to reject function names that start with |
| * 'glX'. |
| * |
| * \bug |
| * Add code to compare \c parameter_signature with the parameter signature of |
| * a static function. In order to do that, we need to find a way to \b get |
| * the parameter signature of a static function. |
| */ |
| |
| int |
| _glapi_add_dispatch( const char * const * function_names, |
| const char * parameter_signature ) |
| { |
| static int next_dynamic_offset = FIRST_DYNAMIC_OFFSET; |
| const char * const real_sig = (parameter_signature != NULL) |
| ? parameter_signature : ""; |
| struct _glapi_function * entry[8]; |
| GLboolean is_static[8]; |
| unsigned i; |
| int offset = ~0; |
| |
| init_glapi_relocs_once(); |
| |
| (void) memset( is_static, 0, sizeof( is_static ) ); |
| (void) memset( entry, 0, sizeof( entry ) ); |
| |
| /* Find the _single_ dispatch offset for all function names that already |
| * exist (and have a dispatch offset). |
| */ |
| |
| for ( i = 0 ; function_names[i] != NULL ; i++ ) { |
| const char * funcName = function_names[i]; |
| int static_offset; |
| int extension_offset; |
| |
| if (funcName[0] != 'g' || funcName[1] != 'l') |
| return -1; |
| |
| /* search built-in functions */ |
| static_offset = get_static_proc_offset(funcName); |
| |
| if (static_offset >= 0) { |
| |
| is_static[i] = GL_TRUE; |
| |
| /* FIXME: Make sure the parameter signatures match! How do we get |
| * FIXME: the parameter signature for static functions? |
| */ |
| |
| if ( (offset != ~0) && (static_offset != offset) ) { |
| return -1; |
| } |
| |
| offset = static_offset; |
| |
| continue; |
| } |
| |
| /* search added extension functions */ |
| entry[i] = get_extension_proc(funcName); |
| |
| if (entry[i] != NULL) { |
| extension_offset = entry[i]->dispatch_offset; |
| |
| /* The offset may be ~0 if the function name was added by |
| * glXGetProcAddress but never filled in by the driver. |
| */ |
| |
| if (extension_offset == ~0) { |
| continue; |
| } |
| |
| if (strcmp(real_sig, entry[i]->parameter_signature) != 0) { |
| return -1; |
| } |
| |
| if ( (offset != ~0) && (extension_offset != offset) ) { |
| return -1; |
| } |
| |
| offset = extension_offset; |
| } |
| } |
| |
| /* If all function names are either new (or with no dispatch offset), |
| * allocate a new dispatch offset. |
| */ |
| |
| if (offset == ~0) { |
| offset = next_dynamic_offset; |
| next_dynamic_offset++; |
| } |
| |
| /* Fill in the dispatch offset for the new function names (and those with |
| * no dispatch offset). |
| */ |
| |
| for ( i = 0 ; function_names[i] != NULL ; i++ ) { |
| if (is_static[i]) { |
| continue; |
| } |
| |
| /* generate entrypoints for new function names */ |
| if (entry[i] == NULL) { |
| entry[i] = add_function_name( function_names[i] ); |
| if (entry[i] == NULL) { |
| /* FIXME: Possible memory leak here. */ |
| return -1; |
| } |
| } |
| |
| if (entry[i]->dispatch_offset == ~0) { |
| set_entry_info( entry[i], real_sig, offset ); |
| } |
| } |
| |
| return offset; |
| } |
| |
| |
| /** |
| * Return offset of entrypoint for named function within dispatch table. |
| */ |
| GLint |
| _glapi_get_proc_offset(const char *funcName) |
| { |
| GLint offset; |
| |
| /* search extension functions first */ |
| offset = get_extension_proc_offset(funcName); |
| if (offset >= 0) |
| return offset; |
| |
| /* search static functions */ |
| return get_static_proc_offset(funcName); |
| } |
| |
| |
| |
| /** |
| * Return pointer to the named function. If the function name isn't found |
| * in the name of static functions, try generating a new API entrypoint on |
| * the fly with assembly language. |
| */ |
| _glapi_proc |
| _glapi_get_proc_address(const char *funcName) |
| { |
| _glapi_proc func; |
| struct _glapi_function * entry; |
| |
| init_glapi_relocs_once(); |
| |
| if (!funcName || funcName[0] != 'g' || funcName[1] != 'l') |
| return NULL; |
| |
| /* search extension functions first */ |
| func = get_extension_proc_address(funcName); |
| if (func) |
| return func; |
| |
| /* search static functions */ |
| func = get_static_proc_address(funcName); |
| if (func) |
| return func; |
| |
| /* generate entrypoint, dispatch offset must be filled in by the driver */ |
| entry = add_function_name(funcName); |
| if (entry == NULL) |
| return NULL; |
| |
| return entry->dispatch_stub; |
| } |
| |
| |
| |
| /** |
| * Return the name of the function at the given dispatch offset. |
| * This is only intended for debugging. |
| */ |
| const char * |
| _glapi_get_proc_name(GLuint offset) |
| { |
| const char * n; |
| |
| /* search built-in functions */ |
| n = get_static_proc_name(offset); |
| if ( n != NULL ) { |
| return n; |
| } |
| |
| /* search added extension functions */ |
| return get_extension_proc_name(offset); |
| } |
| |
| |
| |
| /********************************************************************** |
| * GL API table functions. |
| */ |
| |
| |
| /** |
| * Return size of dispatch table struct as number of functions (or |
| * slots). |
| */ |
| GLuint |
| _glapi_get_dispatch_table_size(void) |
| { |
| /* |
| * The dispatch table size (number of entries) is the size of the |
| * _glapi_table struct plus the number of dynamic entries we can add. |
| * The extra slots can be filled in by DRI drivers that register new |
| * extension functions. |
| */ |
| return FIRST_DYNAMIC_OFFSET + MAX_EXTENSION_FUNCS; |
| } |