src/mesa/glapi/glapi_getproc.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.1
   4  *
   5  * Copyright (C) 1999-2008  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 /**
  26  * \file glapi_getproc.c
  27  *
  28  * Code for implementing glXGetProcAddress(), etc.
  29  * This was originally in glapi.c but refactored out.
  30  */
  31
  32
  33 #ifdef HAVE_DIX_CONFIG_H
  34 #include <dix-config.h>
  35 #include "glapi/mesa.h"
  36 #else
  37 #include "main/glheader.h"
  38 #include "main/compiler.h"
  39 #endif
  40
  41 #include "glapi/glapi.h"
  42 #include "glapi/glapi_priv.h"
  43 #include "glapi/glapitable.h"
  44 #include "glapi/glapioffsets.h"
  45
  46
  47 #if defined(USE_X64_64_ASM) && defined(GLX_USE_TLS)
  48 # define DISPATCH_FUNCTION_SIZE  16
  49 #elif defined(USE_X86_ASM)
  50 # if defined(THREADS) && !defined(GLX_USE_TLS)
  51 #  define DISPATCH_FUNCTION_SIZE  32
  52 # else
  53 #  define DISPATCH_FUNCTION_SIZE  16
  54 # endif
  55 #endif
  56
  57 #if !defined(DISPATCH_FUNCTION_SIZE) && !defined(XFree86Server)
  58 # define NEED_FUNCTION_POINTER
  59 #endif
  60
  61 /* The code in this file is auto-generated with Python */
  62 #include "glapi/glprocs.h"
  63
  64
  65 /**
  66  * Search the table of static entrypoint functions for the named function
  67  * and return the corresponding glprocs_table_t entry.
  68  */
  69 static const glprocs_table_t *
  70 find_entry( const char * n )
  71 {
  72    GLuint i;
  73    for (i = 0; static_functions[i].Name_offset >= 0; i++) {
  74       const char *testName = gl_string_table + static_functions[i].Name_offset;
  75 #ifdef MANGLE
  76       /* skip the "m" prefix on the name */
  77       if (strcmp(testName, n + 1) == 0)
  78 #else
  79       if (strcmp(testName, n) == 0)
  80 #endif
  81       {
  82          return &static_functions[i];
  83       }
  84    }
  85    return NULL;
  86 }
  87
  88
  89 /**
  90  * Return dispatch table offset of the named static (built-in) function.
  91  * Return -1 if function not found.
  92  */
  93 static GLint
  94 get_static_proc_offset(const char *funcName)
  95 {
  96    const glprocs_table_t * const f = find_entry( funcName );
  97    if (f) {
  98       return f->Offset;
  99    }
 100    return -1;
 101 }
 102
 103
 104 #ifdef USE_X86_ASM
 105
 106 #if defined( GLX_USE_TLS )
 107 extern       GLubyte gl_dispatch_functions_start[];
 108 extern       GLubyte gl_dispatch_functions_end[];
 109 #else
 110 extern const GLubyte gl_dispatch_functions_start[];
 111 #endif
 112
 113 #endif /* USE_X86_ASM */
 114
 115
 116 #if !defined(XFree86Server)
 117
 118 /**
 119  * Return dispatch function address for the named static (built-in) function.
 120  * Return NULL if function not found.
 121  */
 122 static _glapi_proc
 123 get_static_proc_address(const char *funcName)
 124 {
 125    const glprocs_table_t * const f = find_entry( funcName );
 126    if (f) {
 127 #if defined(DISPATCH_FUNCTION_SIZE) && defined(GLX_INDIRECT_RENDERING)
 128       return (f->Address == NULL)
 129          ? (_glapi_proc) (gl_dispatch_functions_start
 130                           + (DISPATCH_FUNCTION_SIZE * f->Offset))
 131          : f->Address;
 132 #elif defined(DISPATCH_FUNCTION_SIZE)
 133       return (_glapi_proc) (gl_dispatch_functions_start
 134                             + (DISPATCH_FUNCTION_SIZE * f->Offset));
 135 #else
 136       return f->Address;
 137 #endif
 138    }
 139    else {
 140       return NULL;
 141    }
 142 }
 143
 144 #endif /* !defined(XFree86Server) */
 145
 146
 147
 148 /**
 149  * Return the name of the function at the given offset in the dispatch
 150  * table.  For debugging only.
 151  */
 152 static const char *
 153 get_static_proc_name( GLuint offset )
 154 {
 155    GLuint i;
 156    for (i = 0; static_functions[i].Name_offset >= 0; i++) {
 157       if (static_functions[i].Offset == offset) {
 158          return gl_string_table + static_functions[i].Name_offset;
 159       }
 160    }
 161    return NULL;
 162 }
 163
 164
 165
 166 #if defined(PTHREADS) || defined(GLX_USE_TLS)
 167
 168 /**
 169  * Perform platform-specific GL API entry-point fixups.
 170  */
 171 static void
 172 init_glapi_relocs( void )
 173 {
 174 #if defined(USE_X86_ASM) && defined(GLX_USE_TLS) && !defined(GLX_X86_READONLY_TEXT)
 175     extern unsigned long _x86_get_dispatch(void);
 176     char run_time_patch[] = {
 177        0x65, 0xa1, 0, 0, 0, 0 /* movl %gs:0,%eax */
 178     };
 179     GLuint *offset = (GLuint *) &run_time_patch[2]; /* 32-bits for x86/32 */
 180     const GLubyte * const get_disp = (const GLubyte *) run_time_patch;
 181     GLubyte * curr_func = (GLubyte *) gl_dispatch_functions_start;
 182
 183     *offset = _x86_get_dispatch();
 184     while ( curr_func != (GLubyte *) gl_dispatch_functions_end ) {
 185         (void) memcpy( curr_func, get_disp, sizeof(run_time_patch));
 186         curr_func += DISPATCH_FUNCTION_SIZE;
 187     }
 188 #endif
 189 #ifdef USE_SPARC_ASM
 190     extern void __glapi_sparc_icache_flush(unsigned int *);
 191     static const unsigned int template[] = {
 192 #ifdef GLX_USE_TLS
 193         0x05000000, /* sethi %hi(_glapi_tls_Dispatch), %g2 */
 194         0x8730e00a, /* srl %g3, 10, %g3 */
 195         0x8410a000, /* or %g2, %lo(_glapi_tls_Dispatch), %g2 */
 196 #ifdef __arch64__
 197         0xc259c002, /* ldx [%g7 + %g2], %g1 */
 198         0xc2584003, /* ldx [%g1 + %g3], %g1 */
 199 #else
 200         0xc201c002, /* ld [%g7 + %g2], %g1 */
 201         0xc2004003, /* ld [%g1 + %g3], %g1 */
 202 #endif
 203         0x81c04000, /* jmp %g1 */
 204         0x01000000, /* nop  */
 205 #else
 206 #ifdef __arch64__
 207         0x03000000, /* 64-bit 0x00 --> sethi %hh(_glapi_Dispatch), %g1 */
 208         0x05000000, /* 64-bit 0x04 --> sethi %lm(_glapi_Dispatch), %g2 */
 209         0x82106000, /* 64-bit 0x08 --> or %g1, %hm(_glapi_Dispatch), %g1 */
 210         0x8730e00a, /* 64-bit 0x0c --> srl %g3, 10, %g3 */
 211         0x83287020, /* 64-bit 0x10 --> sllx %g1, 32, %g1 */
 212         0x82004002, /* 64-bit 0x14 --> add %g1, %g2, %g1 */
 213         0xc2586000, /* 64-bit 0x18 --> ldx [%g1 + %lo(_glapi_Dispatch)], %g1 */
 214 #else
 215         0x03000000, /* 32-bit 0x00 --> sethi %hi(_glapi_Dispatch), %g1 */
 216         0x8730e00a, /* 32-bit 0x04 --> srl %g3, 10, %g3 */
 217         0xc2006000, /* 32-bit 0x08 --> ld [%g1 + %lo(_glapi_Dispatch)], %g1 */
 218 #endif
 219         0x80a06000, /*             --> cmp %g1, 0 */
 220         0x02800005, /*             --> be +4*5 */
 221         0x01000000, /*             -->  nop  */
 222 #ifdef __arch64__
 223         0xc2584003, /* 64-bit      --> ldx [%g1 + %g3], %g1 */
 224 #else
 225         0xc2004003, /* 32-bit      --> ld [%g1 + %g3], %g1 */
 226 #endif
 227         0x81c04000, /*             --> jmp %g1 */
 228         0x01000000, /*             --> nop  */
 229 #ifdef __arch64__
 230         0x9de3bf80, /* 64-bit      --> save  %sp, -128, %sp */
 231 #else
 232         0x9de3bfc0, /* 32-bit      --> save  %sp, -64, %sp */
 233 #endif
 234         0xa0100003, /*             --> mov  %g3, %l0 */
 235         0x40000000, /*             --> call _glapi_get_dispatch */
 236         0x01000000, /*             -->  nop */
 237         0x82100008, /*             --> mov %o0, %g1 */
 238         0x86100010, /*             --> mov %l0, %g3 */
 239         0x10bffff7, /*             --> ba -4*9 */
 240         0x81e80000, /*             -->  restore  */
 241 #endif
 242     };
 243 #ifdef GLX_USE_TLS
 244     extern unsigned int __glapi_sparc_tls_stub;
 245     extern unsigned long __glapi_sparc_get_dispatch(void);
 246     unsigned int *code = &__glapi_sparc_tls_stub;
 247     unsigned long dispatch = __glapi_sparc_get_dispatch();
 248 #else
 249     extern unsigned int __glapi_sparc_pthread_stub;
 250     unsigned int *code = &__glapi_sparc_pthread_stub;
 251     unsigned long dispatch = (unsigned long) &_glapi_Dispatch;
 252     unsigned long call_dest = (unsigned long ) &_glapi_get_dispatch;
 253     int idx;
 254 #endif
 255
 256 #if defined(GLX_USE_TLS)
 257     code[0] = template[0] | (dispatch >> 10);
 258     code[1] = template[1];
 259     __glapi_sparc_icache_flush(&code[0]);
 260     code[2] = template[2] | (dispatch & 0x3ff);
 261     code[3] = template[3];
 262     __glapi_sparc_icache_flush(&code[2]);
 263     code[4] = template[4];
 264     code[5] = template[5];
 265     __glapi_sparc_icache_flush(&code[4]);
 266     code[6] = template[6];
 267     __glapi_sparc_icache_flush(&code[6]);
 268 #else
 269 #if defined(__arch64__)
 270     code[0] = template[0] | (dispatch >> (32 + 10));
 271     code[1] = template[1] | ((dispatch & 0xffffffff) >> 10);
 272     __glapi_sparc_icache_flush(&code[0]);
 273     code[2] = template[2] | ((dispatch >> 32) & 0x3ff);
 274     code[3] = template[3];
 275     __glapi_sparc_icache_flush(&code[2]);
 276     code[4] = template[4];
 277     code[5] = template[5];
 278     __glapi_sparc_icache_flush(&code[4]);
 279     code[6] = template[6] | (dispatch & 0x3ff);
 280     idx = 7;
 281 #else
 282     code[0] = template[0] | (dispatch >> 10);
 283     code[1] = template[1];
 284     __glapi_sparc_icache_flush(&code[0]);
 285     code[2] = template[2] | (dispatch & 0x3ff);
 286     idx = 3;
 287 #endif
 288     code[idx + 0] = template[idx + 0];
 289     __glapi_sparc_icache_flush(&code[idx - 1]);
 290     code[idx + 1] = template[idx + 1];
 291     code[idx + 2] = template[idx + 2];
 292     __glapi_sparc_icache_flush(&code[idx + 1]);
 293     code[idx + 3] = template[idx + 3];
 294     code[idx + 4] = template[idx + 4];
 295     __glapi_sparc_icache_flush(&code[idx + 3]);
 296     code[idx + 5] = template[idx + 5];
 297     code[idx + 6] = template[idx + 6];
 298     __glapi_sparc_icache_flush(&code[idx + 5]);
 299     code[idx + 7] = template[idx + 7];
 300     code[idx + 8] = template[idx + 8] |
 301             (((call_dest - ((unsigned long) &code[idx + 8]))
 302               >> 2) & 0x3fffffff);
 303     __glapi_sparc_icache_flush(&code[idx + 7]);
 304     code[idx + 9] = template[idx + 9];
 305     code[idx + 10] = template[idx + 10];
 306     __glapi_sparc_icache_flush(&code[idx + 9]);
 307     code[idx + 11] = template[idx + 11];
 308     code[idx + 12] = template[idx + 12];
 309     __glapi_sparc_icache_flush(&code[idx + 11]);
 310     code[idx + 13] = template[idx + 13];
 311     __glapi_sparc_icache_flush(&code[idx + 13]);
 312 #endif
 313 #endif
 314 }
 315
 316 void
 317 init_glapi_relocs_once( void )
 318 {
 319    static pthread_once_t once_control = PTHREAD_ONCE_INIT;
 320    pthread_once( & once_control, init_glapi_relocs );
 321 }
 322
 323 #else
 324
 325 void
 326 init_glapi_relocs_once( void ) { }
 327
 328 #endif /* defined(PTHREADS) || defined(GLX_USE_TLS) */
 329
 330
 331
 332 /**********************************************************************
 333  * Extension function management.
 334  */
 335
 336
 337 /**
 338  * Track information about a function added to the GL API.
 339  */
 340 struct _glapi_function {
 341    /**
 342     * Name of the function.
 343     */
 344    const char * name;
 345
 346
 347    /**
 348     * Text string that describes the types of the parameters passed to the
 349     * named function.   Parameter types are converted to characters using the
 350     * following rules:
 351     *   - 'i' for \c GLint, \c GLuint, and \c GLenum
 352     *   - 'p' for any pointer type
 353     *   - 'f' for \c GLfloat and \c GLclampf
 354     *   - 'd' for \c GLdouble and \c GLclampd
 355     */
 356    const char * parameter_signature;
 357
 358
 359    /**
 360     * Offset in the dispatch table where the pointer to the real function is
 361     * located.  If the driver has not requested that the named function be
 362     * added to the dispatch table, this will have the value ~0.
 363     */
 364    unsigned dispatch_offset;
 365
 366
 367    /**
 368     * Pointer to the dispatch stub for the named function.
 369     *
 370     * \todo
 371     * The semantic of this field should be changed slightly.  Currently, it
 372     * is always expected to be non-\c NULL.  However, it would be better to
 373     * only allocate the entry-point stub when the application requests the
 374     * function via \c glXGetProcAddress.  This would save memory for all the
 375     * functions that the driver exports but that the application never wants
 376     * to call.
 377     */
 378    _glapi_proc dispatch_stub;
 379 };
 380
 381
 382 /*
 383  * Number of extension functions which we can dynamically add at runtime.
 384  */
 385 #define MAX_EXTENSION_FUNCS 300
 386
 387
 388 static struct _glapi_function ExtEntryTable[MAX_EXTENSION_FUNCS];
 389 static GLuint NumExtEntryPoints = 0;
 390
 391 #ifdef USE_SPARC_ASM
 392 extern void __glapi_sparc_icache_flush(unsigned int *);
 393 #endif
 394
 395 static void
 396 fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset);
 397
 398 /**
 399  * Generate a dispatch function (entrypoint) which jumps through
 400  * the given slot number (offset) in the current dispatch table.
 401  * We need assembly language in order to accomplish this.
 402  */
 403 static _glapi_proc
 404 generate_entrypoint(GLuint functionOffset)
 405 {
 406 #if defined(USE_X86_ASM)
 407    /* 32 is chosen as something of a magic offset.  For x86, the dispatch
 408     * at offset 32 is the first one where the offset in the
 409     * "jmp OFFSET*4(%eax)" can't be encoded in a single byte.
 410     */
 411    const GLubyte * const template_func = gl_dispatch_functions_start
 412      + (DISPATCH_FUNCTION_SIZE * 32);
 413    GLubyte * const code = (GLubyte *) malloc(DISPATCH_FUNCTION_SIZE);
 414
 415
 416    if ( code != NULL ) {
 417       (void) memcpy(code, template_func, DISPATCH_FUNCTION_SIZE);
 418       fill_in_entrypoint_offset( (_glapi_proc) code, functionOffset );
 419    }
 420
 421    return (_glapi_proc) code;
 422 #elif defined(USE_SPARC_ASM)
 423
 424 #if defined(PTHREADS) || defined(GLX_USE_TLS)
 425    static const unsigned int template[] = {
 426       0x07000000, /* sethi %hi(0), %g3 */
 427       0x8210000f, /* mov  %o7, %g1 */
 428       0x40000000, /* call */
 429       0x9e100001, /* mov  %g1, %o7 */
 430    };
 431 #ifdef GLX_USE_TLS
 432    extern unsigned int __glapi_sparc_tls_stub;
 433    unsigned long call_dest = (unsigned long ) &__glapi_sparc_tls_stub;
 434 #else
 435    extern unsigned int __glapi_sparc_pthread_stub;
 436    unsigned long call_dest = (unsigned long ) &__glapi_sparc_pthread_stub;
 437 #endif
 438    unsigned int *code = (unsigned int *) malloc(sizeof(template));
 439    if (code) {
 440       code[0] = template[0] | (functionOffset & 0x3fffff);
 441       code[1] = template[1];
 442       __glapi_sparc_icache_flush(&code[0]);
 443       code[2] = template[2] |
 444          (((call_dest - ((unsigned long) &code[2]))
 445            >> 2) & 0x3fffffff);
 446       code[3] = template[3];
 447       __glapi_sparc_icache_flush(&code[2]);
 448    }
 449    return (_glapi_proc) code;
 450 #endif
 451
 452 #else
 453    (void) functionOffset;
 454    return NULL;
 455 #endif /* USE_*_ASM */
 456 }
 457
 458
 459 /**
 460  * This function inserts a new dispatch offset into the assembly language
 461  * stub that was generated with the preceeding function.
 462  */
 463 static void
 464 fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset)
 465 {
 466 #if defined(USE_X86_ASM)
 467    GLubyte * const code = (GLubyte *) entrypoint;
 468
 469 #if DISPATCH_FUNCTION_SIZE == 32
 470    *((unsigned int *)(code + 11)) = 4 * offset;
 471    *((unsigned int *)(code + 22)) = 4 * offset;
 472 #elif DISPATCH_FUNCTION_SIZE == 16 && defined( GLX_USE_TLS )
 473    *((unsigned int *)(code +  8)) = 4 * offset;
 474 #elif DISPATCH_FUNCTION_SIZE == 16
 475    *((unsigned int *)(code +  7)) = 4 * offset;
 476 #else
 477 # error Invalid DISPATCH_FUNCTION_SIZE!
 478 #endif
 479
 480 #elif defined(USE_SPARC_ASM)
 481    unsigned int *code = (unsigned int *) entrypoint;
 482    code[0] &= ~0x3fffff;
 483    code[0] |= (offset * sizeof(void *)) & 0x3fffff;
 484    __glapi_sparc_icache_flush(&code[0]);
 485 #else
 486
 487    /* an unimplemented architecture */
 488    (void) entrypoint;
 489    (void) offset;
 490
 491 #endif /* USE_*_ASM */
 492 }
 493
 494
 495 /**
 496  * strdup() is actually not a standard ANSI C or POSIX routine.
 497  * Irix will not define it if ANSI mode is in effect.
 498  */
 499 static char *
 500 str_dup(const char *str)
 501 {
 502    char *copy;
 503    copy = (char*) malloc(strlen(str) + 1);
 504    if (!copy)
 505       return NULL;
 506    strcpy(copy, str);
 507    return copy;
 508 }
 509
 510
 511 /**
 512  * Generate new entrypoint
 513  *
 514  * Use a temporary dispatch offset of ~0 (i.e. -1).  Later, when the driver
 515  * calls \c _glapi_add_dispatch we'll put in the proper offset.  If that
 516  * never happens, and the user calls this function, he'll segfault.  That's
 517  * what you get when you try calling a GL function that doesn't really exist.
 518  *
 519  * \param funcName  Name of the function to create an entry-point for.
 520  *
 521  * \sa _glapi_add_entrypoint
 522  */
 523
 524 static struct _glapi_function *
 525 add_function_name( const char * funcName )
 526 {
 527    struct _glapi_function * entry = NULL;
 528
 529    if (NumExtEntryPoints < MAX_EXTENSION_FUNCS) {
 530       _glapi_proc entrypoint = generate_entrypoint(~0);
 531       if (entrypoint != NULL) {
 532          entry = & ExtEntryTable[NumExtEntryPoints];
 533
 534          ExtEntryTable[NumExtEntryPoints].name = str_dup(funcName);
 535          ExtEntryTable[NumExtEntryPoints].parameter_signature = NULL;
 536          ExtEntryTable[NumExtEntryPoints].dispatch_offset = ~0;
 537          ExtEntryTable[NumExtEntryPoints].dispatch_stub = entrypoint;
 538          NumExtEntryPoints++;
 539       }
 540    }
 541
 542    return entry;
 543 }
 544
 545
 546 /**
 547  * Fill-in the dispatch stub for the named function.
 548  *
 549  * This function is intended to be called by a hardware driver.  When called,
 550  * a dispatch stub may be created created for the function.  A pointer to this
 551  * dispatch function will be returned by glXGetProcAddress.
 552  *
 553  * \param function_names       Array of pointers to function names that should
 554  *                             share a common dispatch offset.
 555  * \param parameter_signature  String representing the types of the parameters
 556  *                             passed to the named function.  Parameter types
 557  *                             are converted to characters using the following
 558  *                             rules:
 559  *                               - 'i' for \c GLint, \c GLuint, and \c GLenum
 560  *                               - 'p' for any pointer type
 561  *                               - 'f' for \c GLfloat and \c GLclampf
 562  *                               - 'd' for \c GLdouble and \c GLclampd
 563  *
 564  * \returns
 565  * The offset in the dispatch table of the named function.  A pointer to the
 566  * driver's implementation of the named function should be stored at
 567  * \c dispatch_table[\c offset].  Return -1 if error/problem.
 568  *
 569  * \sa glXGetProcAddress
 570  *
 571  * \warning
 572  * This function can only handle up to 8 names at a time.  As far as I know,
 573  * the maximum number of names ever associated with an existing GL function is
 574  * 4 (\c glPointParameterfSGIS, \c glPointParameterfEXT,
 575  * \c glPointParameterfARB, and \c glPointParameterf), so this should not be
 576  * too painful of a limitation.
 577  *
 578  * \todo
 579  * Determine whether or not \c parameter_signature should be allowed to be
 580  * \c NULL.  It doesn't seem like much of a hardship for drivers to have to
 581  * pass in an empty string.
 582  *
 583  * \todo
 584  * Determine if code should be added to reject function names that start with
 585  * 'glX'.
 586  *
 587  * \bug
 588  * Add code to compare \c parameter_signature with the parameter signature of
 589  * a static function.  In order to do that, we need to find a way to \b get
 590  * the parameter signature of a static function.
 591  */
 592
 593 PUBLIC int
 594 _glapi_add_dispatch( const char * const * function_names,
 595                      const char * parameter_signature )
 596 {
 597    static int next_dynamic_offset = _gloffset_FIRST_DYNAMIC;
 598    const char * const real_sig = (parameter_signature != NULL)
 599      ? parameter_signature : "";
 600    struct _glapi_function * entry[8];
 601    GLboolean is_static[8];
 602    unsigned i;
 603    unsigned j;
 604    int offset = ~0;
 605    int new_offset;
 606
 607
 608    (void) memset( is_static, 0, sizeof( is_static ) );
 609    (void) memset( entry, 0, sizeof( entry ) );
 610
 611    for ( i = 0 ; function_names[i] != NULL ; i++ ) {
 612       /* Do some trivial validation on the name of the function.
 613        */
 614
 615       if (!function_names[i] || function_names[i][0] != 'g' || function_names[i][1] != 'l')
 616          return -1;
 617
 618       /* Determine if the named function already exists.  If the function does
 619        * exist, it must have the same parameter signature as the function
 620        * being added.
 621        */
 622
 623       new_offset = get_static_proc_offset(function_names[i]);
 624       if (new_offset >= 0) {
 625          /* FIXME: Make sure the parameter signatures match!  How do we get
 626           * FIXME: the parameter signature for static functions?
 627           */
 628
 629          if ( (offset != ~0) && (new_offset != offset) ) {
 630             return -1;
 631          }
 632
 633          is_static[i] = GL_TRUE;
 634          offset = new_offset;
 635       }
 636
 637
 638       for ( j = 0 ; j < NumExtEntryPoints ; j++ ) {
 639          if (strcmp(ExtEntryTable[j].name, function_names[i]) == 0) {
 640             /* The offset may be ~0 if the function name was added by
 641              * glXGetProcAddress but never filled in by the driver.
 642              */
 643
 644             if (ExtEntryTable[j].dispatch_offset != ~0) {
 645                if (strcmp(real_sig, ExtEntryTable[j].parameter_signature)
 646                    != 0) {
 647                   return -1;
 648                }
 649
 650                if ( (offset != ~0) && (ExtEntryTable[j].dispatch_offset != offset) ) {
 651                   return -1;
 652                }
 653
 654                offset = ExtEntryTable[j].dispatch_offset;
 655             }
 656
 657             entry[i] = & ExtEntryTable[j];
 658             break;
 659          }
 660       }
 661    }
 662
 663    if (offset == ~0) {
 664       offset = next_dynamic_offset;
 665       next_dynamic_offset++;
 666    }
 667
 668    for ( i = 0 ; function_names[i] != NULL ; i++ ) {
 669       if (! is_static[i] ) {
 670          if (entry[i] == NULL) {
 671             entry[i] = add_function_name( function_names[i] );
 672             if (entry[i] == NULL) {
 673                /* FIXME: Possible memory leak here.
 674                 */
 675                return -1;
 676             }
 677          }
 678
 679          entry[i]->parameter_signature = str_dup(real_sig);
 680          fill_in_entrypoint_offset(entry[i]->dispatch_stub, offset);
 681          entry[i]->dispatch_offset = offset;
 682       }
 683    }
 684
 685    return offset;
 686 }
 687
 688
 689 /**
 690  * Return offset of entrypoint for named function within dispatch table.
 691  */
 692 PUBLIC GLint
 693 _glapi_get_proc_offset(const char *funcName)
 694 {
 695    /* search extension functions first */
 696    GLuint i;
 697    for (i = 0; i < NumExtEntryPoints; i++) {
 698       if (strcmp(ExtEntryTable[i].name, funcName) == 0) {
 699          return ExtEntryTable[i].dispatch_offset;
 700       }
 701    }
 702    /* search static functions */
 703    return get_static_proc_offset(funcName);
 704 }
 705
 706
 707
 708 /**
 709  * Return pointer to the named function.  If the function name isn't found
 710  * in the name of static functions, try generating a new API entrypoint on
 711  * the fly with assembly language.
 712  */
 713 PUBLIC _glapi_proc
 714 _glapi_get_proc_address(const char *funcName)
 715 {
 716    struct _glapi_function * entry;
 717    GLuint i;
 718
 719 #ifdef MANGLE
 720    if (funcName[0] != 'm' || funcName[1] != 'g' || funcName[2] != 'l')
 721       return NULL;
 722 #else
 723    if (funcName[0] != 'g' || funcName[1] != 'l')
 724       return NULL;
 725 #endif
 726
 727    /* search extension functions first */
 728    for (i = 0; i < NumExtEntryPoints; i++) {
 729       if (strcmp(ExtEntryTable[i].name, funcName) == 0) {
 730          return ExtEntryTable[i].dispatch_stub;
 731       }
 732    }
 733
 734 #if !defined( XFree86Server )
 735    /* search static functions */
 736    {
 737       const _glapi_proc func = get_static_proc_address(funcName);
 738       if (func)
 739          return func;
 740    }
 741 #endif /* !defined( XFree86Server ) */
 742
 743    entry = add_function_name(funcName);
 744    return (entry == NULL) ? NULL : entry->dispatch_stub;
 745 }
 746
 747
 748
 749 /**
 750  * Return the name of the function at the given dispatch offset.
 751  * This is only intended for debugging.
 752  */
 753 const char *
 754 _glapi_get_proc_name(GLuint offset)
 755 {
 756    GLuint i;
 757    const char * n;
 758
 759    /* search built-in functions */
 760    n = get_static_proc_name(offset);
 761    if ( n != NULL ) {
 762       return n;
 763    }
 764
 765    /* search added extension functions */
 766    for (i = 0; i < NumExtEntryPoints; i++) {
 767       if (ExtEntryTable[i].dispatch_offset == offset) {
 768          return ExtEntryTable[i].name;
 769       }
 770    }
 771    return NULL;
 772 }
 773
 774
 775
 776 /**********************************************************************
 777  * GL API table functions.
 778  */
 779
 780
 781 /*
 782  * The dispatch table size (number of entries) is the size of the
 783  * _glapi_table struct plus the number of dynamic entries we can add.
 784  * The extra slots can be filled in by DRI drivers that register new extension
 785  * functions.
 786  */
 787 #define DISPATCH_TABLE_SIZE (sizeof(struct _glapi_table) / sizeof(void *) + MAX_EXTENSION_FUNCS)
 788
 789
 790 /**
 791  * Return size of dispatch table struct as number of functions (or
 792  * slots).
 793  */
 794 PUBLIC GLuint
 795 _glapi_get_dispatch_table_size(void)
 796 {
 797    return DISPATCH_TABLE_SIZE;
 798 }
 799
 800
 801 /**
 802  * Make sure there are no NULL pointers in the given dispatch table.
 803  * Intended for debugging purposes.
 804  */
 805 void
 806 _glapi_check_table_not_null(const struct _glapi_table *table)
 807 {
 808 #ifdef EXTRA_DEBUG /* set to DEBUG for extra DEBUG */
 809    const GLuint entries = _glapi_get_dispatch_table_size();
 810    const void **tab = (const void **) table;
 811    GLuint i;
 812    for (i = 1; i < entries; i++) {
 813       assert(tab[i]);
 814    }
 815 #else
 816    (void) table;
 817 #endif
 818 }
 819
 820
 821 /**
 822  * Do some spot checks to be sure that the dispatch table
 823  * slots are assigned correctly. For debugging only.
 824  */
 825 void
 826 _glapi_check_table(const struct _glapi_table *table)
 827 {
 828 #ifdef EXTRA_DEBUG /* set to DEBUG for extra DEBUG */
 829    {
 830       GLuint BeginOffset = _glapi_get_proc_offset("glBegin");
 831       char *BeginFunc = (char*) &table->Begin;
 832       GLuint offset = (BeginFunc - (char *) table) / sizeof(void *);
 833       assert(BeginOffset == _gloffset_Begin);
 834       assert(BeginOffset == offset);
 835    }
 836    {
 837       GLuint viewportOffset = _glapi_get_proc_offset("glViewport");
 838       char *viewportFunc = (char*) &table->Viewport;
 839       GLuint offset = (viewportFunc - (char *) table) / sizeof(void *);
 840       assert(viewportOffset == _gloffset_Viewport);
 841       assert(viewportOffset == offset);
 842    }
 843    {
 844       GLuint VertexPointerOffset = _glapi_get_proc_offset("glVertexPointer");
 845       char *VertexPointerFunc = (char*) &table->VertexPointer;
 846       GLuint offset = (VertexPointerFunc - (char *) table) / sizeof(void *);
 847       assert(VertexPointerOffset == _gloffset_VertexPointer);
 848       assert(VertexPointerOffset == offset);
 849    }
 850    {
 851       GLuint ResetMinMaxOffset = _glapi_get_proc_offset("glResetMinmax");
 852       char *ResetMinMaxFunc = (char*) &table->ResetMinmax;
 853       GLuint offset = (ResetMinMaxFunc - (char *) table) / sizeof(void *);
 854       assert(ResetMinMaxOffset == _gloffset_ResetMinmax);
 855       assert(ResetMinMaxOffset == offset);
 856    }
 857    {
 858       GLuint blendColorOffset = _glapi_get_proc_offset("glBlendColor");
 859       char *blendColorFunc = (char*) &table->BlendColor;
 860       GLuint offset = (blendColorFunc - (char *) table) / sizeof(void *);
 861       assert(blendColorOffset == _gloffset_BlendColor);
 862       assert(blendColorOffset == offset);
 863    }
 864    {
 865       GLuint secondaryColor3fOffset = _glapi_get_proc_offset("glSecondaryColor3fEXT");
 866       char *secondaryColor3fFunc = (char*) &table->SecondaryColor3fEXT;
 867       GLuint offset = (secondaryColor3fFunc - (char *) table) / sizeof(void *);
 868       assert(secondaryColor3fOffset == _gloffset_SecondaryColor3fEXT);
 869       assert(secondaryColor3fOffset == offset);
 870    }
 871    {
 872       GLuint pointParameterivOffset = _glapi_get_proc_offset("glPointParameterivNV");
 873       char *pointParameterivFunc = (char*) &table->PointParameterivNV;
 874       GLuint offset = (pointParameterivFunc - (char *) table) / sizeof(void *);
 875       assert(pointParameterivOffset == _gloffset_PointParameterivNV);
 876       assert(pointParameterivOffset == offset);
 877    }
 878    {
 879       GLuint setFenceOffset = _glapi_get_proc_offset("glSetFenceNV");
 880       char *setFenceFunc = (char*) &table->SetFenceNV;
 881       GLuint offset = (setFenceFunc - (char *) table) / sizeof(void *);
 882       assert(setFenceOffset == _gloffset_SetFenceNV);
 883       assert(setFenceOffset == offset);
 884    }
 885 #else
 886    (void) table;
 887 #endif
 888 }