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diff --git a/src/mesa/glapi/glapi.c b/src/mesa/glapi/glapi.c
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+/*
+ * 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.
+ */
+
+
+
+#include "glheader.h"
+#include "glapi.h"
+#include "glapioffsets.h"
+#include "glapitable.h"
+
+/***** BEGIN NO-OP DISPATCH *****/
+
+static GLboolean WarnFlag = GL_FALSE;
+static _glapi_warning_func warning_func;
+
+#if defined(PTHREADS) || defined(GLX_USE_TLS)
+static void init_glapi_relocs(void);
+#endif
+
+static _glapi_proc generate_entrypoint(GLuint functionOffset);
+static void fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset);
+
+/*
+ * Enable/disable printing of warning messages.
+ */
+PUBLIC void
+_glapi_noop_enable_warnings(GLboolean enable)
+{
+ WarnFlag = enable;
+}
+
+/*
+ * Register a callback function for reporting errors.
+ */
+PUBLIC void
+_glapi_set_warning_func( _glapi_warning_func func )
+{
+ warning_func = func;
+}
+
+static GLboolean
+warn(void)
+{
+ if ((WarnFlag || getenv("MESA_DEBUG") || getenv("LIBGL_DEBUG"))
+ && warning_func) {
+ return GL_TRUE;
+ }
+ else {
+ return GL_FALSE;
+ }
+}
+
+
+#define KEYWORD1 static
+#define KEYWORD2 GLAPIENTRY
+#define NAME(func) NoOp##func
+
+#define F NULL
+
+#define DISPATCH(func, args, msg) \
+ if (warn()) { \
+ warning_func(NULL, "GL User Error: called without context: %s", #func); \
+ }
+
+#define RETURN_DISPATCH(func, args, msg) \
+ if (warn()) { \
+ warning_func(NULL, "GL User Error: called without context: %s", #func); \
+ } \
+ return 0
+
+#define DISPATCH_TABLE_NAME __glapi_noop_table
+#define UNUSED_TABLE_NAME __unused_noop_functions
+
+#define TABLE_ENTRY(name) (_glapi_proc) NoOp##name
+
+static GLint NoOpUnused(void)
+{
+ if (warn()) {
+ warning_func(NULL, "GL User Error: calling extension function without a current context\n");
+ }
+ return 0;
+}
+
+#include "glapitemp.h"
+
+/***** END NO-OP DISPATCH *****/
+
+
+
+/**
+ * \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.
+ *
+ * There is a race condition in setting \c _glapi_Dispatch to \c NULL. It is
+ * possible for the original thread to be setting it at the same instant a new
+ * thread, perhaps running on a different processor, is clearing it. Because
+ * of that, \c ThreadSafe, which can only ever be changed to \c GL_TRUE, is
+ * used to determine whether or not the application is multithreaded.
+ *
+ * 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 __thread struct _glapi_table * _glapi_tls_Dispatch
+ __attribute__((tls_model("initial-exec")))
+ = (struct _glapi_table *) __glapi_noop_table;
+
+PUBLIC __thread 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)
+
+static GLboolean ThreadSafe = GL_FALSE; /**< In thread-safe mode? */
+_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 =
+ (struct _glapi_table *) __glapi_noop_table;
+PUBLIC void *_glapi_Context = NULL;
+
+#endif /* defined(GLX_USE_TLS) */
+/*@}*/
+
+
+/**
+ * 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 = (char*) malloc(strlen(str) + 1);
+ if (!copy)
+ return NULL;
+ strcpy(copy, str);
+ return copy;
+}
+
+
+
+/**
+ * We should call this periodically from a function such as glXMakeCurrent
+ * in order to test if multiple threads are being used.
+ */
+void
+_glapi_check_multithread(void)
+{
+#if defined(THREADS) && !defined(GLX_USE_TLS)
+ if (!ThreadSafe) {
+ static unsigned long knownID;
+ static GLboolean firstCall = GL_TRUE;
+ if (firstCall) {
+ knownID = _glthread_GetID();
+ firstCall = GL_FALSE;
+ }
+ else if (knownID != _glthread_GetID()) {
+ ThreadSafe = GL_TRUE;
+ _glapi_set_dispatch(NULL);
+ }
+ }
+ else if (!_glapi_get_dispatch()) {
+ /* make sure that this thread's dispatch pointer isn't null */
+ _glapi_set_dispatch(NULL);
+ }
+#endif
+}
+
+
+
+/**
+ * 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)
+{
+ (void) __unused_noop_functions; /* silence a warning */
+#if defined(GLX_USE_TLS)
+ _glapi_tls_Context = context;
+#elif defined(THREADS)
+ _glthread_SetTSD(&ContextTSD, context);
+ _glapi_Context = (ThreadSafe) ? NULL : 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;
+#elif defined(THREADS)
+ if (ThreadSafe) {
+ return _glthread_GetTSD(&ContextTSD);
+ }
+ else {
+ return _glapi_Context;
+ }
+#else
+ return _glapi_Context;
+#endif
+}
+
+
+
+/**
+ * Set the global or per-thread dispatch table pointer.
+ * If the dispatch parameter is NULL we'll plug in the no-op dispatch
+ * table (__glapi_noop_table).
+ */
+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 (!dispatch) {
+ /* use the no-op functions */
+ dispatch = (struct _glapi_table *) __glapi_noop_table;
+ }
+#ifdef DEBUG
+ else {
+ _glapi_check_table(dispatch);
+ }
+#endif
+
+#if defined(GLX_USE_TLS)
+ _glapi_tls_Dispatch = dispatch;
+#elif defined(THREADS)
+ _glthread_SetTSD(&_gl_DispatchTSD, (void *) dispatch);
+ _glapi_Dispatch = (ThreadSafe) ? NULL : 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;
+#elif defined(THREADS)
+ api = (ThreadSafe)
+ ? (struct _glapi_table *) _glthread_GetTSD(&_gl_DispatchTSD)
+ : _glapi_Dispatch;
+#else
+ api = _glapi_Dispatch;
+#endif
+ return api;
+}
+
+
+
+/***
+ *** The rest of this file is pretty much concerned with GetProcAddress
+ *** functionality.
+ ***/
+
+#if !defined( USE_X86_ASM ) && !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
+
+# if defined(THREADS) && !defined(GLX_USE_TLS)
+# define X86_DISPATCH_FUNCTION_SIZE 32
+# else
+# define X86_DISPATCH_FUNCTION_SIZE 16
+# 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) {
+#ifdef USE_X86_ASM
+ return (_glapi_proc) (gl_dispatch_functions_start
+ + (X86_DISPATCH_FUNCTION_SIZE * f->Offset));
+#else
+ return f->Address;
+#endif
+ }
+ else {
+ return NULL;
+ }
+}
+
+#endif /* !defined(XFree86Server) && !defined(XGLServer) */
+
+
+
+/**
+ * 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.
+ */
+
+/*
+ * 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;
+
+
+ /**
+ * 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;
+
+#ifdef USE_SPARC_ASM
+extern void __glapi_sparc_icache_flush(unsigned int *);
+#endif
+
+/**
+ * Generate a dispatch function (entrypoint) which jumps through
+ * the given slot number (offset) in the current dispatch table.
+ * We need assembly language in order to accomplish this.
+ */
+static _glapi_proc
+generate_entrypoint(GLuint functionOffset)
+{
+#if defined(USE_X86_ASM)
+ /* 32 is chosen as something of a magic offset. For x86, the dispatch
+ * at offset 32 is the first one where the offset in the
+ * "jmp OFFSET*4(%eax)" can't be encoded in a single byte.
+ */
+ const GLubyte * const template_func = gl_dispatch_functions_start
+ + (X86_DISPATCH_FUNCTION_SIZE * 32);
+ GLubyte * const code = (GLubyte *) malloc( X86_DISPATCH_FUNCTION_SIZE );
+
+
+ if ( code != NULL ) {
+ (void) memcpy( code, template_func, X86_DISPATCH_FUNCTION_SIZE );
+ fill_in_entrypoint_offset( (_glapi_proc) code, functionOffset );
+ }
+
+ return (_glapi_proc) code;
+#elif defined(USE_SPARC_ASM)
+
+#ifdef __arch64__
+ static const unsigned int insn_template[] = {
+ 0x05000000, /* sethi %uhi(_glapi_Dispatch), %g2 */
+ 0x03000000, /* sethi %hi(_glapi_Dispatch), %g1 */
+ 0x8410a000, /* or %g2, %ulo(_glapi_Dispatch), %g2 */
+ 0x82106000, /* or %g1, %lo(_glapi_Dispatch), %g1 */
+ 0x8528b020, /* sllx %g2, 32, %g2 */
+ 0xc2584002, /* ldx [%g1 + %g2], %g1 */
+ 0x05000000, /* sethi %hi(8 * glapioffset), %g2 */
+ 0x8410a000, /* or %g2, %lo(8 * glapioffset), %g2 */
+ 0xc6584002, /* ldx [%g1 + %g2], %g3 */
+ 0x81c0c000, /* jmpl %g3, %g0 */
+ 0x01000000 /* nop */
+ };
+#else
+ static const unsigned int insn_template[] = {
+ 0x03000000, /* sethi %hi(_glapi_Dispatch), %g1 */
+ 0xc2006000, /* ld [%g1 + %lo(_glapi_Dispatch)], %g1 */
+ 0xc6006000, /* ld [%g1 + %lo(4*glapioffset)], %g3 */
+ 0x81c0c000, /* jmpl %g3, %g0 */
+ 0x01000000 /* nop */
+ };
+#endif /* __arch64__ */
+ unsigned int *code = (unsigned int *) malloc(sizeof(insn_template));
+ unsigned long glapi_addr = (unsigned long) &_glapi_Dispatch;
+ if (code) {
+ memcpy(code, insn_template, sizeof(insn_template));
+
+#ifdef __arch64__
+ code[0] |= (glapi_addr >> (32 + 10));
+ code[1] |= ((glapi_addr & 0xffffffff) >> 10);
+ __glapi_sparc_icache_flush(&code[0]);
+ code[2] |= ((glapi_addr >> 32) & ((1 << 10) - 1));
+ code[3] |= (glapi_addr & ((1 << 10) - 1));
+ __glapi_sparc_icache_flush(&code[2]);
+ code[6] |= ((functionOffset * 8) >> 10);
+ code[7] |= ((functionOffset * 8) & ((1 << 10) - 1));
+ __glapi_sparc_icache_flush(&code[6]);
+#else
+ code[0] |= (glapi_addr >> 10);
+ code[1] |= (glapi_addr & ((1 << 10) - 1));
+ __glapi_sparc_icache_flush(&code[0]);
+ code[2] |= (functionOffset * 4);
+ __glapi_sparc_icache_flush(&code[2]);
+#endif /* __arch64__ */
+ }
+ return (_glapi_proc) code;
+#else
+ (void) functionOffset;
+ return NULL;
+#endif /* USE_*_ASM */
+}
+
+
+/**
+ * This function inserts a new dispatch offset into the assembly language
+ * stub that was generated with the preceeding function.
+ */
+static void
+fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset)
+{
+#if defined(USE_X86_ASM)
+ GLubyte * const code = (GLubyte *) entrypoint;
+
+#if X86_DISPATCH_FUNCTION_SIZE == 32
+ *((unsigned int *)(code + 11)) = 4 * offset;
+ *((unsigned int *)(code + 22)) = 4 * offset;
+#elif X86_DISPATCH_FUNCTION_SIZE == 16 && defined( GLX_USE_TLS )
+ *((unsigned int *)(code + 8)) = 4 * offset;
+#elif X86_DISPATCH_FUNCTION_SIZE == 16
+ *((unsigned int *)(code + 7)) = 4 * offset;
+#else
+# error Invalid X86_DISPATCH_FUNCTION_SIZE!
+#endif
+
+#elif defined(USE_SPARC_ASM)
+
+ /* XXX this hasn't been tested! */
+ unsigned int *code = (unsigned int *) entrypoint;
+#ifdef __arch64__
+ code[6] = 0x05000000; /* sethi %hi(8 * glapioffset), %g2 */
+ code[7] = 0x8410a000; /* or %g2, %lo(8 * glapioffset), %g2 */
+ code[6] |= ((offset * 8) >> 10);
+ code[7] |= ((offset * 8) & ((1 << 10) - 1));
+ __glapi_sparc_icache_flush(&code[6]);
+#else /* __arch64__ */
+ code[2] = 0xc6006000; /* ld [%g1 + %lo(4*glapioffset)], %g3 */
+ code[2] |= (offset * 4);
+ __glapi_sparc_icache_flush(&code[2]);
+#endif /* __arch64__ */
+
+#else
+
+ /* an unimplemented architecture */
+ (void) entrypoint;
+ (void) offset;
+
+#endif /* USE_*_ASM */
+}
+
+
+/**
+ * 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) {
+ _glapi_proc entrypoint = generate_entrypoint(~0);
+ if (entrypoint != NULL) {
+ entry = & ExtEntryTable[NumExtEntryPoints];
+
+ ExtEntryTable[NumExtEntryPoints].name = str_dup(funcName);
+ ExtEntryTable[NumExtEntryPoints].parameter_signature = NULL;
+ ExtEntryTable[NumExtEntryPoints].dispatch_offset = ~0;
+ ExtEntryTable[NumExtEntryPoints].dispatch_stub = entrypoint;
+ 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] || 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) {
+ /* FIXME: Possible memory leak here.
+ */
+ return -1;
+ }
+ }
+
+ entry[i]->parameter_signature = str_dup(real_sig);
+ fill_in_entrypoint_offset(entry[i]->dispatch_stub, offset);
+ entry[i]->dispatch_offset = offset;
+ }
+ }
+
+ return offset;
+}
+
+
+/**
+ * Return offset of entrypoint for named function within dispatch table.
+ */
+PUBLIC GLint
+_glapi_get_proc_offset(const char *funcName)
+{
+ /* search extension functions first */
+ GLuint i;
+ for (i = 0; i < NumExtEntryPoints; i++) {
+ if (strcmp(ExtEntryTable[i].name, funcName) == 0) {
+ return ExtEntryTable[i].dispatch_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)
+{
+ struct _glapi_function * entry;
+ GLuint i;
+
+#ifdef MANGLE
+ if (funcName[0] != 'm' || funcName[1] != 'g' || funcName[2] != 'l')
+ return NULL;
+#else
+ if (funcName[0] != 'g' || funcName[1] != 'l')
+ return NULL;
+#endif
+
+ /* search extension functions first */
+ for (i = 0; i < NumExtEntryPoints; i++) {
+ if (strcmp(ExtEntryTable[i].name, funcName) == 0) {
+ return ExtEntryTable[i].dispatch_stub;
+ }
+ }
+
+#if !defined( XFree86Server ) && !defined( XGLServer )
+ /* search static functions */
+ {
+ const _glapi_proc func = get_static_proc_address(funcName);
+ if (func)
+ return func;
+ }
+#endif /* !defined( XFree86Server ) */
+
+ entry = add_function_name(funcName);
+ return (entry == NULL) ? NULL : 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)
+{
+ GLuint i;
+ const char * n;
+
+ /* search built-in functions */
+ n = get_static_proc_name(offset);
+ if ( n != NULL ) {
+ return n;
+ }
+
+ /* search added extension functions */
+ for (i = 0; i < NumExtEntryPoints; i++) {
+ if (ExtEntryTable[i].dispatch_offset == offset) {
+ return ExtEntryTable[i].name;
+ }
+ }
+ 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;
+}
+
+
+
+/**
+ * Make sure there are no NULL pointers in the given dispatch table.
+ * Intended for debugging purposes.
+ */
+void
+_glapi_check_table(const struct _glapi_table *table)
+{
+#ifdef DEBUG
+ const GLuint entries = _glapi_get_dispatch_table_size();
+ const void **tab = (const void **) table;
+ GLuint i;
+ for (i = 1; i < entries; i++) {
+ assert(tab[i]);
+ }
+
+ /* Do some spot checks to be sure that the dispatch table
+ * slots are assigned correctly.
+ */
+ {
+ GLuint BeginOffset = _glapi_get_proc_offset("glBegin");
+ char *BeginFunc = (char*) &table->Begin;
+ GLuint offset = (BeginFunc - (char *) table) / sizeof(void *);
+ assert(BeginOffset == _gloffset_Begin);
+ assert(BeginOffset == offset);
+ }
+ {
+ GLuint viewportOffset = _glapi_get_proc_offset("glViewport");
+ char *viewportFunc = (char*) &table->Viewport;
+ GLuint offset = (viewportFunc - (char *) table) / sizeof(void *);
+ assert(viewportOffset == _gloffset_Viewport);
+ assert(viewportOffset == offset);
+ }
+ {
+ GLuint VertexPointerOffset = _glapi_get_proc_offset("glVertexPointer");
+ char *VertexPointerFunc = (char*) &table->VertexPointer;
+ GLuint offset = (VertexPointerFunc - (char *) table) / sizeof(void *);
+ assert(VertexPointerOffset == _gloffset_VertexPointer);
+ assert(VertexPointerOffset == offset);
+ }
+ {
+ GLuint ResetMinMaxOffset = _glapi_get_proc_offset("glResetMinmax");
+ char *ResetMinMaxFunc = (char*) &table->ResetMinmax;
+ GLuint offset = (ResetMinMaxFunc - (char *) table) / sizeof(void *);
+ assert(ResetMinMaxOffset == _gloffset_ResetMinmax);
+ assert(ResetMinMaxOffset == offset);
+ }
+ {
+ GLuint blendColorOffset = _glapi_get_proc_offset("glBlendColor");
+ char *blendColorFunc = (char*) &table->BlendColor;
+ GLuint offset = (blendColorFunc - (char *) table) / sizeof(void *);
+ assert(blendColorOffset == _gloffset_BlendColor);
+ assert(blendColorOffset == offset);
+ }
+ {
+ GLuint istextureOffset = _glapi_get_proc_offset("glIsTextureEXT");
+ char *istextureFunc = (char*) &table->IsTextureEXT;
+ GLuint offset = (istextureFunc - (char *) table) / sizeof(void *);
+ assert(istextureOffset == _gloffset_IsTextureEXT);
+ assert(istextureOffset == offset);
+ }
+ {
+ GLuint secondaryColor3fOffset = _glapi_get_proc_offset("glSecondaryColor3fEXT");
+ char *secondaryColor3fFunc = (char*) &table->SecondaryColor3fEXT;
+ GLuint offset = (secondaryColor3fFunc - (char *) table) / sizeof(void *);
+ assert(secondaryColor3fOffset == _gloffset_SecondaryColor3fEXT);
+ assert(secondaryColor3fOffset == offset);
+ assert(_glapi_get_proc_address("glSecondaryColor3fEXT") == (_glapi_proc) &glSecondaryColor3fEXT);
+ }
+ {
+ GLuint pointParameterivOffset = _glapi_get_proc_offset("glPointParameterivNV");
+ char *pointParameterivFunc = (char*) &table->PointParameterivNV;
+ GLuint offset = (pointParameterivFunc - (char *) table) / sizeof(void *);
+ assert(pointParameterivOffset == _gloffset_PointParameterivNV);
+ assert(pointParameterivOffset == offset);
+ assert(_glapi_get_proc_address("glPointParameterivNV") == (_glapi_proc) &glPointParameterivNV);
+ }
+ {
+ GLuint setFenceOffset = _glapi_get_proc_offset("glSetFenceNV");
+ char *setFenceFunc = (char*) &table->SetFenceNV;
+ GLuint offset = (setFenceFunc - (char *) table) / sizeof(void *);
+ assert(setFenceOffset == _gloffset_SetFenceNV);
+ assert(setFenceOffset == offset);
+ assert(_glapi_get_proc_address("glSetFenceNV") == (_glapi_proc) &glSetFenceNV);
+ }
+#else
+ (void) table;
+#endif
+}
+
+
+#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 )
+ extern void * _x86_get_dispatch(void);
+ const GLubyte * const get_disp = (const GLubyte *) _x86_get_dispatch;
+ GLubyte * curr_func = (GLubyte *) gl_dispatch_functions_start;
+
+
+ while ( curr_func != (GLubyte *) gl_dispatch_functions_end ) {
+ (void) memcpy( curr_func, get_disp, 6 );
+ curr_func += X86_DISPATCH_FUNCTION_SIZE;
+ }
+#endif /* defined( USE_X86_ASM ) && defined( GLX_USE_TLS ) */
+}
+#endif