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Diffstat (limited to 'glx/glapi.c')
| -rw-r--r-- | glx/glapi.c | 581 |
1 files changed, 581 insertions, 0 deletions
diff --git a/glx/glapi.c b/glx/glapi.c new file mode 100644 index 0000000..92395ae --- /dev/null +++ b/glx/glapi.c @@ -0,0 +1,581 @@ +/* + * Mesa 3-D graphics library + * Version: 6.5 + * + * Copyright (C) 1999-2006 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 + * BRIAN PAUL 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. + */ + + +/* + * This file manages the OpenGL API dispatch layer. + * The dispatch table (struct _glapi_table) is basically just a list + * of function pointers. + * There are functions to set/get the current dispatch table for the + * current thread and to manage registration/dispatch of dynamically + * added extension functions. + * + * It's intended that this file and the other glapi*.[ch] files are + * flexible enough to be reused in several places: XFree86, DRI- + * based libGL.so, and perhaps the SGI SI. + * + * NOTE: There are no dependencies on Mesa in this code. + * + * Versions (API changes): + * 2000/02/23 - original version for Mesa 3.3 and XFree86 4.0 + * 2001/01/16 - added dispatch override feature for Mesa 3.5 + * 2002/06/28 - added _glapi_set_warning_func(), Mesa 4.1. + * 2002/10/01 - _glapi_get_proc_address() will now generate new entrypoints + * itself (using offset ~0). _glapi_add_entrypoint() can be + * called afterward and it'll fill in the correct dispatch + * offset. This allows DRI libGL to avoid probing for DRI + * drivers! No changes to the public glapi interface. + */ + + + +#ifdef HAVE_DIX_CONFIG_H + +#include <dix-config.h> +#include <X11/Xfuncproto.h> +#include <os.h> +#define PUBLIC _X_EXPORT + +#else + +#include "glheader.h" + +#endif + +#include <stdlib.h> +#include <string.h> +#ifdef DEBUG +#include <assert.h> +#endif + +#include "glapi.h" +#include "glapioffsets.h" +#include "glapitable.h" + +#if defined(PTHREADS) || defined(GLX_USE_TLS) +static void init_glapi_relocs(void); +#endif + +/** + * \name Current dispatch and current context control variables + * + * Depending on whether or not multithreading is support, and the type of + * support available, several variables are used to store the current context + * pointer and the current dispatch table pointer. In the non-threaded case, + * the variables \c _glapi_Dispatch and \c _glapi_Context are used for this + * purpose. + * + * In the "normal" threaded case, the variables \c _glapi_Dispatch and + * \c _glapi_Context will be \c NULL if an application is detected as being + * multithreaded. Single-threaded applications will use \c _glapi_Dispatch + * and \c _glapi_Context just like the case without any threading support. + * When \c _glapi_Dispatch and \c _glapi_Context are \c NULL, the thread state + * data \c _gl_DispatchTSD and \c ContextTSD are used. Drivers and the + * static dispatch functions access these variables via \c _glapi_get_dispatch + * and \c _glapi_get_context. + * + * In the TLS case, the variables \c _glapi_Dispatch and \c _glapi_Context are + * hardcoded to \c NULL. Instead the TLS variables \c _glapi_tls_Dispatch and + * \c _glapi_tls_Context are used. Having \c _glapi_Dispatch and + * \c _glapi_Context be hardcoded to \c NULL maintains binary compatability + * between TLS enabled loaders and non-TLS DRI drivers. + */ +/*@{*/ +#if defined(GLX_USE_TLS) + +PUBLIC TLS struct _glapi_table * _glapi_tls_Dispatch + __attribute__((tls_model("initial-exec"))) = NULL; + +PUBLIC TLS void * _glapi_tls_Context + __attribute__((tls_model("initial-exec"))); + +PUBLIC const struct _glapi_table *_glapi_Dispatch = NULL; +PUBLIC const void *_glapi_Context = NULL; + +#else + +#if defined(THREADS) + +_glthread_TSD _gl_DispatchTSD; /**< Per-thread dispatch pointer */ +static _glthread_TSD ContextTSD; /**< Per-thread context pointer */ + +#if defined(WIN32_THREADS) +void FreeTSD(_glthread_TSD *p); +void FreeAllTSD(void) +{ + FreeTSD(&_gl_DispatchTSD); + FreeTSD(&ContextTSD); +} +#endif /* defined(WIN32_THREADS) */ + +#endif /* defined(THREADS) */ + +PUBLIC struct _glapi_table *_glapi_Dispatch = NULL; +PUBLIC void *_glapi_Context = NULL; + +#endif /* defined(GLX_USE_TLS) */ +/*@}*/ + +/* + * xserver's gl is not multithreaded, we promise. + */ +PUBLIC void +_glapi_check_multithread(void) +{ +} + +/** + * Set the current context pointer for this thread. + * The context pointer is an opaque type which should be cast to + * void from the real context pointer type. + */ +PUBLIC void +_glapi_set_context(void *context) +{ +#if defined(GLX_USE_TLS) + _glapi_tls_Context = context; +#elif defined(THREADS) + _glthread_SetTSD(&ContextTSD, context); + _glapi_Context = context; +#else + _glapi_Context = context; +#endif +} + + + +/** + * Get the current context pointer for this thread. + * The context pointer is an opaque type which should be cast from + * void to the real context pointer type. + */ +PUBLIC void * +_glapi_get_context(void) +{ +#if defined(GLX_USE_TLS) + return _glapi_tls_Context; +#else + return _glapi_Context; +#endif +} + + + +/** + * Set the global or per-thread dispatch table pointer. + */ +PUBLIC void +_glapi_set_dispatch(struct _glapi_table *dispatch) +{ +#if defined(PTHREADS) || defined(GLX_USE_TLS) + static pthread_once_t once_control = PTHREAD_ONCE_INIT; + pthread_once( & once_control, init_glapi_relocs ); +#endif + +#if defined(GLX_USE_TLS) + _glapi_tls_Dispatch = dispatch; +#elif defined(THREADS) + _glthread_SetTSD(&_gl_DispatchTSD, (void *) dispatch); + _glapi_Dispatch = dispatch; +#else /*THREADS*/ + _glapi_Dispatch = dispatch; +#endif /*THREADS*/ +} + + + +/** + * Return pointer to current dispatch table for calling thread. + */ +PUBLIC struct _glapi_table * +_glapi_get_dispatch(void) +{ + struct _glapi_table * api; +#if defined(GLX_USE_TLS) + api = _glapi_tls_Dispatch; +#else + api = _glapi_Dispatch; +#endif + return api; +} + + + +/*** + *** The rest of this file is pretty much concerned with GetProcAddress + *** functionality. + ***/ + +#if defined(USE_X64_64_ASM) && defined(GLX_USE_TLS) +# define DISPATCH_FUNCTION_SIZE 16 +#elif defined(USE_X86_ASM) +# if defined(THREADS) && !defined(GLX_USE_TLS) +# define DISPATCH_FUNCTION_SIZE 32 +# else +# define DISPATCH_FUNCTION_SIZE 16 +# endif +#endif + +#if !defined(DISPATCH_FUNCTION_SIZE) && !defined(XFree86Server) && !defined(XGLServer) +# define NEED_FUNCTION_POINTER +#endif + +/* The code in this file is auto-generated with Python */ +#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 * +find_entry( 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 = find_entry( funcName ); + if (f) { + return f->Offset; + } + return -1; +} + + +#if !defined(XFree86Server) && !defined(XGLServer) +#ifdef USE_X86_ASM + +#if defined( GLX_USE_TLS ) +extern GLubyte gl_dispatch_functions_start[]; +extern GLubyte gl_dispatch_functions_end[]; +#else +extern const GLubyte gl_dispatch_functions_start[]; +#endif + +#endif /* USE_X86_ASM */ + + +/** + * 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 = find_entry( funcName ); + if (f) { +#if defined(DISPATCH_FUNCTION_SIZE) && defined(GLX_INDIRECT_RENDERING) + return (f->Address == NULL) + ? (_glapi_proc) (gl_dispatch_functions_start + + (DISPATCH_FUNCTION_SIZE * f->Offset)) + : f->Address; +#elif defined(DISPATCH_FUNCTION_SIZE) + return (_glapi_proc) (gl_dispatch_functions_start + + (DISPATCH_FUNCTION_SIZE * f->Offset)); +#else + return f->Address; +#endif + } + else { + return NULL; + } +} + +#endif /* !defined(XFree86Server) && !defined(XGLServer) */ + +/********************************************************************** + * Extension function management. + */ + +/* + * Number of extension functions which we can dynamically add at runtime. + */ +#define MAX_EXTENSION_FUNCS 300 + + +/* + * 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. + */ +#define DISPATCH_TABLE_SIZE (sizeof(struct _glapi_table) / sizeof(void *) + MAX_EXTENSION_FUNCS) + + +/** + * 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; +}; + +static struct _glapi_function ExtEntryTable[MAX_EXTENSION_FUNCS]; +static GLuint NumExtEntryPoints = 0; + +/** + * 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; + + if (NumExtEntryPoints < MAX_EXTENSION_FUNCS) { + entry = &ExtEntryTable[NumExtEntryPoints]; + + ExtEntryTable[NumExtEntryPoints].name = strdup(funcName); + ExtEntryTable[NumExtEntryPoints].parameter_signature = NULL; + ExtEntryTable[NumExtEntryPoints].dispatch_offset = ~0; + NumExtEntryPoints++; + } + + 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 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]. + * + * \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. + */ + +PUBLIC int +_glapi_add_dispatch( const char * const * function_names, + const char * parameter_signature ) +{ + static int next_dynamic_offset = _gloffset_FIRST_DYNAMIC; + const char * const real_sig = (parameter_signature != NULL) + ? parameter_signature : ""; + struct _glapi_function * entry[8]; + GLboolean is_static[8]; + unsigned i; + unsigned j; + int offset = ~0; + int new_offset; + + + (void) memset(is_static, 0, sizeof(is_static)); + (void) memset(entry, 0, sizeof(entry)); + + for (i = 0 ; function_names[i] != NULL ; i++) { + /* Do some trivial validation on the name of the function. */ + + if (function_names[i][0] != 'g' || function_names[i][1] != 'l') + return GL_FALSE; + + /* Determine if the named function already exists. If the function does + * exist, it must have the same parameter signature as the function + * being added. + */ + + new_offset = get_static_proc_offset(function_names[i]); + if (new_offset >= 0) { + /* FIXME: Make sure the parameter signatures match! How do we get + * FIXME: the parameter signature for static functions? + */ + + if ((offset != ~0) && (new_offset != offset)) { + return -1; + } + + is_static[i] = GL_TRUE; + offset = new_offset; + } + + for (j = 0; j < NumExtEntryPoints; j++) { + if (strcmp(ExtEntryTable[j].name, function_names[i]) == 0) { + /* The offset may be ~0 if the function name was added by + * glXGetProcAddress but never filled in by the driver. + */ + + if (ExtEntryTable[j].dispatch_offset != ~0) { + if (strcmp(real_sig, ExtEntryTable[j].parameter_signature) != 0) + return -1; + + if ((offset != ~0) && (ExtEntryTable[j].dispatch_offset != offset)) { + return -1; + } + + offset = ExtEntryTable[j].dispatch_offset; + } + + entry[i] = & ExtEntryTable[j]; + break; + } + } + } + + if (offset == ~0) { + offset = next_dynamic_offset; + next_dynamic_offset++; + } + + for (i = 0 ; function_names[i] != NULL ; i++) { + if (!is_static[i]) { + if (entry[i] == NULL) { + entry[i] = add_function_name(function_names[i]); + if (entry[i] == NULL) + return -1; + } + + entry[i]->parameter_signature = strdup(real_sig); + entry[i]->dispatch_offset = offset; + } + } + + return offset; +} + +/* + * glXGetProcAddress doesn't exist in the protocol, the drivers never call + * this themselves, and neither does the server. warn if it happens though. + */ +PUBLIC _glapi_proc +_glapi_get_proc_address(const char *funcName) +{ + ErrorF("_glapi_get_proc_address called!\n"); + return NULL; +} + +/** + * Return size of dispatch table struct as number of functions (or + * slots). + */ +PUBLIC GLuint +_glapi_get_dispatch_table_size(void) +{ + return DISPATCH_TABLE_SIZE; +} + +#if defined(PTHREADS) || defined(GLX_USE_TLS) +/** + * Perform platform-specific GL API entry-point fixups. + */ +static void +init_glapi_relocs( void ) +{ +#if defined(USE_X86_ASM) && defined(GLX_USE_TLS) && !defined(GLX_X86_READONLY_TEXT) + extern unsigned long _x86_get_dispatch(void); + char run_time_patch[] = { + 0x65, 0xa1, 0, 0, 0, 0 /* movl %gs:0,%eax */ + }; + GLuint *offset = (GLuint *) &run_time_patch[2]; /* 32-bits for x86/32 */ + const GLubyte * const get_disp = (const GLubyte *) run_time_patch; + GLubyte * curr_func = (GLubyte *) gl_dispatch_functions_start; + + *offset = _x86_get_dispatch(); + while ( curr_func != (GLubyte *) gl_dispatch_functions_end ) { + (void) memcpy( curr_func, get_disp, sizeof(run_time_patch)); + curr_func += DISPATCH_FUNCTION_SIZE; + } +#endif +} +#endif /* defined(PTHREADS) || defined(GLX_USE_TLS) */ |