src/mesa/glapi/glapi.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5
   4  *
   5  * Copyright (C) 1999-2006  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 /*
  27  * This file manages the OpenGL API dispatch layer.
  28  * The dispatch table (struct _glapi_table) is basically just a list
  29  * of function pointers.
  30  * There are functions to set/get the current dispatch table for the
  31  * current thread and to manage registration/dispatch of dynamically
  32  * added extension functions.
  33  *
  34  * It's intended that this file and the other glapi*.[ch] files are
  35  * flexible enough to be reused in several places:  XFree86, DRI-
  36  * based libGL.so, and perhaps the SGI SI.
  37  *
  38  * NOTE: There are no dependencies on Mesa in this code.
  39  *
  40  * Versions (API changes):
  41  *   2000/02/23  - original version for Mesa 3.3 and XFree86 4.0
  42  *   2001/01/16  - added dispatch override feature for Mesa 3.5
  43  *   2002/06/28  - added _glapi_set_warning_func(), Mesa 4.1.
  44  *   2002/10/01  - _glapi_get_proc_address() will now generate new entrypoints
  45  *                 itself (using offset ~0).  _glapi_add_entrypoint() can be
  46  *                 called afterward and it'll fill in the correct dispatch
  47  *                 offset.  This allows DRI libGL to avoid probing for DRI
  48  *                 drivers!  No changes to the public glapi interface.
  49  */
  50
  51
  52
  53 #include "glheader.h"
  54 #include "glapi.h"
  55 #include "glapioffsets.h"
  56 #include "glapitable.h"
  57
  58 /***** BEGIN NO-OP DISPATCH *****/
  59
  60 static GLboolean WarnFlag = GL_FALSE;
  61 static _glapi_warning_func warning_func;
  62
  63 #if defined(PTHREADS) || defined(GLX_USE_TLS)
  64 static void init_glapi_relocs(void);
  65 #endif
  66
  67 static _glapi_proc generate_entrypoint(GLuint functionOffset);
  68 static void fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset);
  69
  70 /*
  71  * Enable/disable printing of warning messages.
  72  */
  73 PUBLIC void
  74 _glapi_noop_enable_warnings(GLboolean enable)
  75 {
  76    WarnFlag = enable;
  77 }
  78
  79 /*
  80  * Register a callback function for reporting errors.
  81  */
  82 PUBLIC void
  83 _glapi_set_warning_func( _glapi_warning_func func )
  84 {
  85    warning_func = func;
  86 }
  87
  88 static GLboolean
  89 warn(void)
  90 {
  91    if ((WarnFlag || getenv("MESA_DEBUG") || getenv("LIBGL_DEBUG"))
  92        && warning_func) {
  93       return GL_TRUE;
  94    }
  95    else {
  96       return GL_FALSE;
  97    }
  98 }
  99
 100
 101 #define KEYWORD1 static
 102 #define KEYWORD2 GLAPIENTRY
 103 #define NAME(func)  NoOp##func
 104
 105 #define F NULL
 106
 107 #define DISPATCH(func, args, msg)                                             \
 108    if (warn()) {                                                              \
 109       warning_func(NULL, "GL User Error: called without context: %s", #func); \
 110    }
 111
 112 #define RETURN_DISPATCH(func, args, msg)                                      \
 113    if (warn()) {                                                              \
 114       warning_func(NULL, "GL User Error: called without context: %s", #func); \
 115    }                                                                          \
 116    return 0
 117
 118 #define DISPATCH_TABLE_NAME __glapi_noop_table
 119 #define UNUSED_TABLE_NAME __unused_noop_functions
 120
 121 #define TABLE_ENTRY(name) (_glapi_proc) NoOp##name
 122
 123 static GLint NoOpUnused(void)
 124 {
 125    if (warn()) {
 126       warning_func(NULL, "GL User Error: calling extension function without a current context\n");
 127    }
 128    return 0;
 129 }
 130
 131 #include "glapitemp.h"
 132
 133 /***** END NO-OP DISPATCH *****/
 134
 135
 136
 137 /**
 138  * \name Current dispatch and current context control variables
 139  *
 140  * Depending on whether or not multithreading is support, and the type of
 141  * support available, several variables are used to store the current context
 142  * pointer and the current dispatch table pointer.  In the non-threaded case,
 143  * the variables \c _glapi_Dispatch and \c _glapi_Context are used for this
 144  * purpose.
 145  *
 146  * In the "normal" threaded case, the variables \c _glapi_Dispatch and
 147  * \c _glapi_Context will be \c NULL if an application is detected as being
 148  * multithreaded.  Single-threaded applications will use \c _glapi_Dispatch
 149  * and \c _glapi_Context just like the case without any threading support.
 150  * When \c _glapi_Dispatch and \c _glapi_Context are \c NULL, the thread state
 151  * data \c _gl_DispatchTSD and \c ContextTSD are used.  Drivers and the
 152  * static dispatch functions access these variables via \c _glapi_get_dispatch
 153  * and \c _glapi_get_context.
 154  *
 155  * There is a race condition in setting \c _glapi_Dispatch to \c NULL.  It is
 156  * possible for the original thread to be setting it at the same instant a new
 157  * thread, perhaps running on a different processor, is clearing it.  Because
 158  * of that, \c ThreadSafe, which can only ever be changed to \c GL_TRUE, is
 159  * used to determine whether or not the application is multithreaded.
 160  *
 161  * In the TLS case, the variables \c _glapi_Dispatch and \c _glapi_Context are
 162  * hardcoded to \c NULL.  Instead the TLS variables \c _glapi_tls_Dispatch and
 163  * \c _glapi_tls_Context are used.  Having \c _glapi_Dispatch and
 164  * \c _glapi_Context be hardcoded to \c NULL maintains binary compatability
 165  * between TLS enabled loaders and non-TLS DRI drivers.
 166  */
 167 /*@{*/
 168 #if defined(GLX_USE_TLS)
 169
 170 PUBLIC __thread struct _glapi_table * _glapi_tls_Dispatch
 171     __attribute__((tls_model("initial-exec")))
 172     = (struct _glapi_table *) __glapi_noop_table;
 173
 174 PUBLIC __thread void * _glapi_tls_Context
 175     __attribute__((tls_model("initial-exec")));
 176
 177 PUBLIC const struct _glapi_table *_glapi_Dispatch = NULL;
 178 PUBLIC const void *_glapi_Context = NULL;
 179
 180 #else
 181
 182 #if defined(THREADS)
 183
 184 static GLboolean ThreadSafe = GL_FALSE;  /**< In thread-safe mode? */
 185 _glthread_TSD _gl_DispatchTSD;           /**< Per-thread dispatch pointer */
 186 static _glthread_TSD ContextTSD;         /**< Per-thread context pointer */
 187
 188 #if defined(WIN32_THREADS)
 189 void FreeTSD(_glthread_TSD *p);
 190 void FreeAllTSD(void)
 191 {
 192    FreeTSD(&_gl_DispatchTSD);
 193    FreeTSD(&ContextTSD);
 194 }
 195 #endif /* defined(WIN32_THREADS) */
 196
 197 #endif /* defined(THREADS) */
 198
 199 PUBLIC struct _glapi_table *_glapi_Dispatch =
 200   (struct _glapi_table *) __glapi_noop_table;
 201 PUBLIC void *_glapi_Context = NULL;
 202
 203 #endif /* defined(GLX_USE_TLS) */
 204 /*@}*/
 205
 206
 207 /**
 208  * strdup() is actually not a standard ANSI C or POSIX routine.
 209  * Irix will not define it if ANSI mode is in effect.
 210  */
 211 static char *
 212 str_dup(const char *str)
 213 {
 214    char *copy;
 215    copy = (char*) malloc(strlen(str) + 1);
 216    if (!copy)
 217       return NULL;
 218    strcpy(copy, str);
 219    return copy;
 220 }
 221
 222
 223
 224 /**
 225  * We should call this periodically from a function such as glXMakeCurrent
 226  * in order to test if multiple threads are being used.
 227  */
 228 void
 229 _glapi_check_multithread(void)
 230 {
 231 #if defined(THREADS) && !defined(GLX_USE_TLS)
 232    if (!ThreadSafe) {
 233       static unsigned long knownID;
 234       static GLboolean firstCall = GL_TRUE;
 235       if (firstCall) {
 236          knownID = _glthread_GetID();
 237          firstCall = GL_FALSE;
 238       }
 239       else if (knownID != _glthread_GetID()) {
 240          ThreadSafe = GL_TRUE;
 241          _glapi_set_dispatch(NULL);
 242       }
 243    }
 244    else if (!_glapi_get_dispatch()) {
 245       /* make sure that this thread's dispatch pointer isn't null */
 246       _glapi_set_dispatch(NULL);
 247    }
 248 #endif
 249 }
 250
 251
 252
 253 /**
 254  * Set the current context pointer for this thread.
 255  * The context pointer is an opaque type which should be cast to
 256  * void from the real context pointer type.
 257  */
 258 PUBLIC void
 259 _glapi_set_context(void *context)
 260 {
 261    (void) __unused_noop_functions; /* silence a warning */
 262 #if defined(GLX_USE_TLS)
 263    _glapi_tls_Context = context;
 264 #elif defined(THREADS)
 265    _glthread_SetTSD(&ContextTSD, context);
 266    _glapi_Context = (ThreadSafe) ? NULL : context;
 267 #else
 268    _glapi_Context = context;
 269 #endif
 270 }
 271
 272
 273
 274 /**
 275  * Get the current context pointer for this thread.
 276  * The context pointer is an opaque type which should be cast from
 277  * void to the real context pointer type.
 278  */
 279 PUBLIC void *
 280 _glapi_get_context(void)
 281 {
 282 #if defined(GLX_USE_TLS)
 283    return _glapi_tls_Context;
 284 #elif defined(THREADS)
 285    if (ThreadSafe) {
 286       return _glthread_GetTSD(&ContextTSD);
 287    }
 288    else {
 289       return _glapi_Context;
 290    }
 291 #else
 292    return _glapi_Context;
 293 #endif
 294 }
 295
 296
 297
 298 /**
 299  * Set the global or per-thread dispatch table pointer.
 300  * If the dispatch parameter is NULL we'll plug in the no-op dispatch
 301  * table (__glapi_noop_table).
 302  */
 303 PUBLIC void
 304 _glapi_set_dispatch(struct _glapi_table *dispatch)
 305 {
 306 #if defined(PTHREADS) || defined(GLX_USE_TLS)
 307    static pthread_once_t once_control = PTHREAD_ONCE_INIT;
 308    pthread_once( & once_control, init_glapi_relocs );
 309 #endif
 310
 311    if (!dispatch) {
 312       /* use the no-op functions */
 313       dispatch = (struct _glapi_table *) __glapi_noop_table;
 314    }
 315 #ifdef DEBUG
 316    else {
 317       _glapi_check_table(dispatch);
 318    }
 319 #endif
 320
 321 #if defined(GLX_USE_TLS)
 322    _glapi_tls_Dispatch = dispatch;
 323 #elif defined(THREADS)
 324    _glthread_SetTSD(&_gl_DispatchTSD, (void *) dispatch);
 325    _glapi_Dispatch = (ThreadSafe) ? NULL : dispatch;
 326 #else /*THREADS*/
 327    _glapi_Dispatch = dispatch;
 328 #endif /*THREADS*/
 329 }
 330
 331
 332
 333 /**
 334  * Return pointer to current dispatch table for calling thread.
 335  */
 336 PUBLIC struct _glapi_table *
 337 _glapi_get_dispatch(void)
 338 {
 339    struct _glapi_table * api;
 340 #if defined(GLX_USE_TLS)
 341    api = _glapi_tls_Dispatch;
 342 #elif defined(THREADS)
 343    api = (ThreadSafe)
 344      ? (struct _glapi_table *) _glthread_GetTSD(&_gl_DispatchTSD)
 345      : _glapi_Dispatch;
 346 #else
 347    api = _glapi_Dispatch;
 348 #endif
 349    return api;
 350 }
 351
 352
 353
 354 /***
 355  *** The rest of this file is pretty much concerned with GetProcAddress
 356  *** functionality.
 357  ***/
 358
 359 #if !defined( USE_X86_ASM ) && !defined( XFree86Server ) && !defined ( XGLServer )
 360 #define NEED_FUNCTION_POINTER
 361 #endif
 362
 363 /* The code in this file is auto-generated with Python */
 364 #include "glprocs.h"
 365
 366
 367 /**
 368  * Search the table of static entrypoint functions for the named function
 369  * and return the corresponding glprocs_table_t entry.
 370  */
 371 static const glprocs_table_t *
 372 find_entry( const char * n )
 373 {
 374    GLuint i;
 375    for (i = 0; static_functions[i].Name_offset >= 0; i++) {
 376       const char *testName = gl_string_table + static_functions[i].Name_offset;
 377       if (strcmp(testName, n) == 0) {
 378          return &static_functions[i];
 379       }
 380    }
 381    return NULL;
 382 }
 383
 384
 385 /**
 386  * Return dispatch table offset of the named static (built-in) function.
 387  * Return -1 if function not found.
 388  */
 389 static GLint
 390 get_static_proc_offset(const char *funcName)
 391 {
 392    const glprocs_table_t * const f = find_entry( funcName );
 393    if (f) {
 394       return f->Offset;
 395    }
 396    return -1;
 397 }
 398
 399
 400 #if !defined(XFree86Server) && !defined(XGLServer)
 401 #ifdef USE_X86_ASM
 402
 403 #if defined( GLX_USE_TLS )
 404 extern       GLubyte gl_dispatch_functions_start[];
 405 extern       GLubyte gl_dispatch_functions_end[];
 406 #else
 407 extern const GLubyte gl_dispatch_functions_start[];
 408 #endif
 409
 410 # if defined(THREADS) && !defined(GLX_USE_TLS)
 411 #  define X86_DISPATCH_FUNCTION_SIZE  32
 412 # else
 413 #  define X86_DISPATCH_FUNCTION_SIZE  16
 414 # endif
 415
 416 #endif /* USE_X86_ASM */
 417
 418
 419 /**
 420  * Return dispatch function address for the named static (built-in) function.
 421  * Return NULL if function not found.
 422  */
 423 static _glapi_proc
 424 get_static_proc_address(const char *funcName)
 425 {
 426    const glprocs_table_t * const f = find_entry( funcName );
 427    if (f) {
 428 #ifdef USE_X86_ASM
 429       return (_glapi_proc) (gl_dispatch_functions_start
 430                             + (X86_DISPATCH_FUNCTION_SIZE * f->Offset));
 431 #else
 432       return f->Address;
 433 #endif
 434    }
 435    else {
 436       return NULL;
 437    }
 438 }
 439
 440 #endif /* !defined(XFree86Server) && !defined(XGLServer) */
 441
 442
 443
 444 /**
 445  * Return the name of the function at the given offset in the dispatch
 446  * table.  For debugging only.
 447  */
 448 static const char *
 449 get_static_proc_name( GLuint offset )
 450 {
 451    GLuint i;
 452    for (i = 0; static_functions[i].Name_offset >= 0; i++) {
 453       if (static_functions[i].Offset == offset) {
 454          return gl_string_table + static_functions[i].Name_offset;
 455       }
 456    }
 457    return NULL;
 458 }
 459
 460
 461
 462 /**********************************************************************
 463  * Extension function management.
 464  */
 465
 466 /*
 467  * Number of extension functions which we can dynamically add at runtime.
 468  */
 469 #define MAX_EXTENSION_FUNCS 300
 470
 471
 472 /*
 473  * The dispatch table size (number of entries) is the size of the
 474  * _glapi_table struct plus the number of dynamic entries we can add.
 475  * The extra slots can be filled in by DRI drivers that register new extension
 476  * functions.
 477  */
 478 #define DISPATCH_TABLE_SIZE (sizeof(struct _glapi_table) / sizeof(void *) + MAX_EXTENSION_FUNCS)
 479
 480
 481 /**
 482  * Track information about a function added to the GL API.
 483  */
 484 struct _glapi_function {
 485    /**
 486     * Name of the function.
 487     */
 488    const char * name;
 489
 490
 491    /**
 492     * Text string that describes the types of the parameters passed to the
 493     * named function.   Parameter types are converted to characters using the
 494     * following rules:
 495     *   - 'i' for \c GLint, \c GLuint, and \c GLenum
 496     *   - 'p' for any pointer type
 497     *   - 'f' for \c GLfloat and \c GLclampf
 498     *   - 'd' for \c GLdouble and \c GLclampd
 499     */
 500    const char * parameter_signature;
 501
 502
 503    /**
 504     * Offset in the dispatch table where the pointer to the real function is
 505     * located.  If the driver has not requested that the named function be
 506     * added to the dispatch table, this will have the value ~0.
 507     */
 508    unsigned dispatch_offset;
 509
 510
 511    /**
 512     * Pointer to the dispatch stub for the named function.
 513     *
 514     * \todo
 515     * The semantic of this field should be changed slightly.  Currently, it
 516     * is always expected to be non-\c NULL.  However, it would be better to
 517     * only allocate the entry-point stub when the application requests the
 518     * function via \c glXGetProcAddress.  This would save memory for all the
 519     * functions that the driver exports but that the application never wants
 520     * to call.
 521     */
 522    _glapi_proc dispatch_stub;
 523 };
 524
 525
 526 static struct _glapi_function ExtEntryTable[MAX_EXTENSION_FUNCS];
 527 static GLuint NumExtEntryPoints = 0;
 528
 529 #ifdef USE_SPARC_ASM
 530 extern void __glapi_sparc_icache_flush(unsigned int *);
 531 #endif
 532
 533 /**
 534  * Generate a dispatch function (entrypoint) which jumps through
 535  * the given slot number (offset) in the current dispatch table.
 536  * We need assembly language in order to accomplish this.
 537  */
 538 static _glapi_proc
 539 generate_entrypoint(GLuint functionOffset)
 540 {
 541 #if defined(USE_X86_ASM)
 542    /* 32 is chosen as something of a magic offset.  For x86, the dispatch
 543     * at offset 32 is the first one where the offset in the
 544     * "jmp OFFSET*4(%eax)" can't be encoded in a single byte.
 545     */
 546    const GLubyte * const template_func = gl_dispatch_functions_start
 547      + (X86_DISPATCH_FUNCTION_SIZE * 32);
 548    GLubyte * const code = (GLubyte *) malloc( X86_DISPATCH_FUNCTION_SIZE );
 549
 550
 551    if ( code != NULL ) {
 552       (void) memcpy( code, template_func, X86_DISPATCH_FUNCTION_SIZE );
 553       fill_in_entrypoint_offset( (_glapi_proc) code, functionOffset );
 554    }
 555
 556    return (_glapi_proc) code;
 557 #elif defined(USE_SPARC_ASM)
 558
 559 #ifdef __arch64__
 560    static const unsigned int insn_template[] = {
 561            0x05000000,  /* sethi        %uhi(_glapi_Dispatch), %g2      */
 562            0x03000000,  /* sethi        %hi(_glapi_Dispatch), %g1       */
 563            0x8410a000,  /* or           %g2, %ulo(_glapi_Dispatch), %g2 */
 564            0x82106000,  /* or           %g1, %lo(_glapi_Dispatch), %g1  */
 565            0x8528b020,  /* sllx         %g2, 32, %g2                    */
 566            0xc2584002,  /* ldx          [%g1 + %g2], %g1                */
 567            0x05000000,  /* sethi        %hi(8 * glapioffset), %g2       */
 568            0x8410a000,  /* or           %g2, %lo(8 * glapioffset), %g2  */
 569            0xc6584002,  /* ldx          [%g1 + %g2], %g3                */
 570            0x81c0c000,  /* jmpl         %g3, %g0                        */
 571            0x01000000   /*  nop                                         */
 572    };
 573 #else
 574    static const unsigned int insn_template[] = {
 575            0x03000000,  /* sethi        %hi(_glapi_Dispatch), %g1         */
 576            0xc2006000,  /* ld           [%g1 + %lo(_glapi_Dispatch)], %g1 */
 577            0xc6006000,  /* ld           [%g1 + %lo(4*glapioffset)], %g3   */
 578            0x81c0c000,  /* jmpl         %g3, %g0                          */
 579            0x01000000   /*  nop                                           */
 580    };
 581 #endif /* __arch64__ */
 582    unsigned int *code = (unsigned int *) malloc(sizeof(insn_template));
 583    unsigned long glapi_addr = (unsigned long) &_glapi_Dispatch;
 584    if (code) {
 585       memcpy(code, insn_template, sizeof(insn_template));
 586
 587 #ifdef __arch64__
 588       code[0] |= (glapi_addr >> (32 + 10));
 589       code[1] |= ((glapi_addr & 0xffffffff) >> 10);
 590       __glapi_sparc_icache_flush(&code[0]);
 591       code[2] |= ((glapi_addr >> 32) & ((1 << 10) - 1));
 592       code[3] |= (glapi_addr & ((1 << 10) - 1));
 593       __glapi_sparc_icache_flush(&code[2]);
 594       code[6] |= ((functionOffset * 8) >> 10);
 595       code[7] |= ((functionOffset * 8) & ((1 << 10) - 1));
 596       __glapi_sparc_icache_flush(&code[6]);
 597 #else
 598       code[0] |= (glapi_addr >> 10);
 599       code[1] |= (glapi_addr & ((1 << 10) - 1));
 600       __glapi_sparc_icache_flush(&code[0]);
 601       code[2] |= (functionOffset * 4);
 602       __glapi_sparc_icache_flush(&code[2]);
 603 #endif /* __arch64__ */
 604    }
 605    return (_glapi_proc) code;
 606 #else
 607    (void) functionOffset;
 608    return NULL;
 609 #endif /* USE_*_ASM */
 610 }
 611
 612
 613 /**
 614  * This function inserts a new dispatch offset into the assembly language
 615  * stub that was generated with the preceeding function.
 616  */
 617 static void
 618 fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset)
 619 {
 620 #if defined(USE_X86_ASM)
 621    GLubyte * const code = (GLubyte *) entrypoint;
 622
 623 #if X86_DISPATCH_FUNCTION_SIZE == 32
 624    *((unsigned int *)(code + 11)) = 4 * offset;
 625    *((unsigned int *)(code + 22)) = 4 * offset;
 626 #elif X86_DISPATCH_FUNCTION_SIZE == 16 && defined( GLX_USE_TLS )
 627    *((unsigned int *)(code +  8)) = 4 * offset;
 628 #elif X86_DISPATCH_FUNCTION_SIZE == 16
 629    *((unsigned int *)(code +  7)) = 4 * offset;
 630 #else
 631 # error Invalid X86_DISPATCH_FUNCTION_SIZE!
 632 #endif
 633
 634 #elif defined(USE_SPARC_ASM)
 635
 636    /* XXX this hasn't been tested! */
 637    unsigned int *code = (unsigned int *) entrypoint;
 638 #ifdef __arch64__
 639    code[6] = 0x05000000;  /* sethi      %hi(8 * glapioffset), %g2       */
 640    code[7] = 0x8410a000;  /* or         %g2, %lo(8 * glapioffset), %g2  */
 641    code[6] |= ((offset * 8) >> 10);
 642    code[7] |= ((offset * 8) & ((1 << 10) - 1));
 643    __glapi_sparc_icache_flush(&code[6]);
 644 #else /* __arch64__ */
 645    code[2] = 0xc6006000;  /* ld         [%g1 + %lo(4*glapioffset)], %g3   */
 646    code[2] |= (offset * 4);
 647    __glapi_sparc_icache_flush(&code[2]);
 648 #endif /* __arch64__ */
 649
 650 #else
 651
 652    /* an unimplemented architecture */
 653    (void) entrypoint;
 654    (void) offset;
 655
 656 #endif /* USE_*_ASM */
 657 }
 658
 659
 660 /**
 661  * Generate new entrypoint
 662  *
 663  * Use a temporary dispatch offset of ~0 (i.e. -1).  Later, when the driver
 664  * calls \c _glapi_add_dispatch we'll put in the proper offset.  If that
 665  * never happens, and the user calls this function, he'll segfault.  That's
 666  * what you get when you try calling a GL function that doesn't really exist.
 667  *
 668  * \param funcName  Name of the function to create an entry-point for.
 669  *
 670  * \sa _glapi_add_entrypoint
 671  */
 672
 673 static struct _glapi_function *
 674 add_function_name( const char * funcName )
 675 {
 676    struct _glapi_function * entry = NULL;
 677
 678    if (NumExtEntryPoints < MAX_EXTENSION_FUNCS) {
 679       _glapi_proc entrypoint = generate_entrypoint(~0);
 680       if (entrypoint != NULL) {
 681          entry = & ExtEntryTable[NumExtEntryPoints];
 682
 683          ExtEntryTable[NumExtEntryPoints].name = str_dup(funcName);
 684          ExtEntryTable[NumExtEntryPoints].parameter_signature = NULL;
 685          ExtEntryTable[NumExtEntryPoints].dispatch_offset = ~0;
 686          ExtEntryTable[NumExtEntryPoints].dispatch_stub = entrypoint;
 687          NumExtEntryPoints++;
 688       }
 689    }
 690
 691    return entry;
 692 }
 693
 694
 695 /**
 696  * Fill-in the dispatch stub for the named function.
 697  *
 698  * This function is intended to be called by a hardware driver.  When called,
 699  * a dispatch stub may be created created for the function.  A pointer to this
 700  * dispatch function will be returned by glXGetProcAddress.
 701  *
 702  * \param function_names       Array of pointers to function names that should
 703  *                             share a common dispatch offset.
 704  * \param parameter_signature  String representing the types of the parameters
 705  *                             passed to the named function.  Parameter types
 706  *                             are converted to characters using the following
 707  *                             rules:
 708  *                               - 'i' for \c GLint, \c GLuint, and \c GLenum
 709  *                               - 'p' for any pointer type
 710  *                               - 'f' for \c GLfloat and \c GLclampf
 711  *                               - 'd' for \c GLdouble and \c GLclampd
 712  *
 713  * \returns
 714  * The offset in the dispatch table of the named function.  A pointer to the
 715  * driver's implementation of the named function should be stored at
 716  * \c dispatch_table[\c offset].
 717  *
 718  * \sa glXGetProcAddress
 719  *
 720  * \warning
 721  * This function can only handle up to 8 names at a time.  As far as I know,
 722  * the maximum number of names ever associated with an existing GL function is
 723  * 4 (\c glPointParameterfSGIS, \c glPointParameterfEXT,
 724  * \c glPointParameterfARB, and \c glPointParameterf), so this should not be
 725  * too painful of a limitation.
 726  *
 727  * \todo
 728  * Determine whether or not \c parameter_signature should be allowed to be
 729  * \c NULL.  It doesn't seem like much of a hardship for drivers to have to
 730  * pass in an empty string.
 731  *
 732  * \todo
 733  * Determine if code should be added to reject function names that start with
 734  * 'glX'.
 735  *
 736  * \bug
 737  * Add code to compare \c parameter_signature with the parameter signature of
 738  * a static function.  In order to do that, we need to find a way to \b get
 739  * the parameter signature of a static function.
 740  */
 741
 742 PUBLIC int
 743 _glapi_add_dispatch( const char * const * function_names,
 744                      const char * parameter_signature )
 745 {
 746    static int next_dynamic_offset = _gloffset_FIRST_DYNAMIC;
 747    const char * const real_sig = (parameter_signature != NULL)
 748      ? parameter_signature : "";
 749    struct _glapi_function * entry[8];
 750    GLboolean is_static[8];
 751    unsigned i;
 752    unsigned j;
 753    int offset = ~0;
 754    int new_offset;
 755
 756
 757    (void) memset( is_static, 0, sizeof( is_static ) );
 758    (void) memset( entry, 0, sizeof( entry ) );
 759
 760    for ( i = 0 ; function_names[i] != NULL ; i++ ) {
 761       /* Do some trivial validation on the name of the function.
 762        */
 763
 764       if (!function_names[i] || function_names[i][0] != 'g' || function_names[i][1] != 'l')
 765         return GL_FALSE;
 766
 767       /* Determine if the named function already exists.  If the function does
 768        * exist, it must have the same parameter signature as the function
 769        * being added.
 770        */
 771
 772       new_offset = get_static_proc_offset(function_names[i]);
 773       if (new_offset >= 0) {
 774          /* FIXME: Make sure the parameter signatures match!  How do we get
 775           * FIXME: the parameter signature for static functions?
 776           */
 777
 778          if ( (offset != ~0) && (new_offset != offset) ) {
 779             return -1;
 780          }
 781
 782          is_static[i] = GL_TRUE;
 783          offset = new_offset;
 784       }
 785
 786
 787       for ( j = 0 ; j < NumExtEntryPoints ; j++ ) {
 788          if (strcmp(ExtEntryTable[j].name, function_names[i]) == 0) {
 789             /* The offset may be ~0 if the function name was added by
 790              * glXGetProcAddress but never filled in by the driver.
 791              */
 792
 793             if (ExtEntryTable[j].dispatch_offset != ~0) {
 794                if (strcmp(real_sig, ExtEntryTable[j].parameter_signature)
 795                    != 0) {
 796                   return -1;
 797                }
 798
 799                if ( (offset != ~0) && (ExtEntryTable[j].dispatch_offset != offset) ) {
 800                   return -1;
 801                }
 802
 803                offset = ExtEntryTable[j].dispatch_offset;
 804             }
 805
 806             entry[i] = & ExtEntryTable[j];
 807             break;
 808          }
 809       }
 810    }
 811
 812    if (offset == ~0) {
 813       offset = next_dynamic_offset;
 814       next_dynamic_offset++;
 815    }
 816
 817    for ( i = 0 ; function_names[i] != NULL ; i++ ) {
 818       if (! is_static[i] ) {
 819          if (entry[i] == NULL) {
 820             entry[i] = add_function_name( function_names[i] );
 821             if (entry[i] == NULL) {
 822                /* FIXME: Possible memory leak here.
 823                 */
 824                return -1;
 825             }
 826          }
 827
 828          entry[i]->parameter_signature = str_dup(real_sig);
 829          fill_in_entrypoint_offset(entry[i]->dispatch_stub, offset);
 830          entry[i]->dispatch_offset = offset;
 831       }
 832    }
 833
 834    return offset;
 835 }
 836
 837
 838 /**
 839  * Return offset of entrypoint for named function within dispatch table.
 840  */
 841 PUBLIC GLint
 842 _glapi_get_proc_offset(const char *funcName)
 843 {
 844    /* search extension functions first */
 845    GLuint i;
 846    for (i = 0; i < NumExtEntryPoints; i++) {
 847       if (strcmp(ExtEntryTable[i].name, funcName) == 0) {
 848          return ExtEntryTable[i].dispatch_offset;
 849       }
 850    }
 851    /* search static functions */
 852    return get_static_proc_offset(funcName);
 853 }
 854
 855
 856
 857 /**
 858  * Return pointer to the named function.  If the function name isn't found
 859  * in the name of static functions, try generating a new API entrypoint on
 860  * the fly with assembly language.
 861  */
 862 _glapi_proc
 863 _glapi_get_proc_address(const char *funcName)
 864 {
 865    struct _glapi_function * entry;
 866    GLuint i;
 867
 868 #ifdef MANGLE
 869    if (funcName[0] != 'm' || funcName[1] != 'g' || funcName[2] != 'l')
 870       return NULL;
 871 #else
 872    if (funcName[0] != 'g' || funcName[1] != 'l')
 873       return NULL;
 874 #endif
 875
 876    /* search extension functions first */
 877    for (i = 0; i < NumExtEntryPoints; i++) {
 878       if (strcmp(ExtEntryTable[i].name, funcName) == 0) {
 879          return ExtEntryTable[i].dispatch_stub;
 880       }
 881    }
 882
 883 #if !defined( XFree86Server ) && !defined( XGLServer )
 884    /* search static functions */
 885    {
 886       const _glapi_proc func = get_static_proc_address(funcName);
 887       if (func)
 888          return func;
 889    }
 890 #endif /* !defined( XFree86Server ) */
 891
 892    entry = add_function_name(funcName);
 893    return (entry == NULL) ? NULL : entry->dispatch_stub;
 894 }
 895
 896
 897
 898 /**
 899  * Return the name of the function at the given dispatch offset.
 900  * This is only intended for debugging.
 901  */
 902 const char *
 903 _glapi_get_proc_name(GLuint offset)
 904 {
 905    GLuint i;
 906    const char * n;
 907
 908    /* search built-in functions */
 909    n = get_static_proc_name(offset);
 910    if ( n != NULL ) {
 911       return n;
 912    }
 913
 914    /* search added extension functions */
 915    for (i = 0; i < NumExtEntryPoints; i++) {
 916       if (ExtEntryTable[i].dispatch_offset == offset) {
 917          return ExtEntryTable[i].name;
 918       }
 919    }
 920    return NULL;
 921 }
 922
 923
 924
 925 /**
 926  * Return size of dispatch table struct as number of functions (or
 927  * slots).
 928  */
 929 PUBLIC GLuint
 930 _glapi_get_dispatch_table_size(void)
 931 {
 932    return DISPATCH_TABLE_SIZE;
 933 }
 934
 935
 936
 937 /**
 938  * Make sure there are no NULL pointers in the given dispatch table.
 939  * Intended for debugging purposes.
 940  */
 941 void
 942 _glapi_check_table(const struct _glapi_table *table)
 943 {
 944 #ifdef DEBUG
 945    const GLuint entries = _glapi_get_dispatch_table_size();
 946    const void **tab = (const void **) table;
 947    GLuint i;
 948    for (i = 1; i < entries; i++) {
 949       assert(tab[i]);
 950    }
 951
 952    /* Do some spot checks to be sure that the dispatch table
 953     * slots are assigned correctly.
 954     */
 955    {
 956       GLuint BeginOffset = _glapi_get_proc_offset("glBegin");
 957       char *BeginFunc = (char*) &table->Begin;
 958       GLuint offset = (BeginFunc - (char *) table) / sizeof(void *);
 959       assert(BeginOffset == _gloffset_Begin);
 960       assert(BeginOffset == offset);
 961    }
 962    {
 963       GLuint viewportOffset = _glapi_get_proc_offset("glViewport");
 964       char *viewportFunc = (char*) &table->Viewport;
 965       GLuint offset = (viewportFunc - (char *) table) / sizeof(void *);
 966       assert(viewportOffset == _gloffset_Viewport);
 967       assert(viewportOffset == offset);
 968    }
 969    {
 970       GLuint VertexPointerOffset = _glapi_get_proc_offset("glVertexPointer");
 971       char *VertexPointerFunc = (char*) &table->VertexPointer;
 972       GLuint offset = (VertexPointerFunc - (char *) table) / sizeof(void *);
 973       assert(VertexPointerOffset == _gloffset_VertexPointer);
 974       assert(VertexPointerOffset == offset);
 975    }
 976    {
 977       GLuint ResetMinMaxOffset = _glapi_get_proc_offset("glResetMinmax");
 978       char *ResetMinMaxFunc = (char*) &table->ResetMinmax;
 979       GLuint offset = (ResetMinMaxFunc - (char *) table) / sizeof(void *);
 980       assert(ResetMinMaxOffset == _gloffset_ResetMinmax);
 981       assert(ResetMinMaxOffset == offset);
 982    }
 983    {
 984       GLuint blendColorOffset = _glapi_get_proc_offset("glBlendColor");
 985       char *blendColorFunc = (char*) &table->BlendColor;
 986       GLuint offset = (blendColorFunc - (char *) table) / sizeof(void *);
 987       assert(blendColorOffset == _gloffset_BlendColor);
 988       assert(blendColorOffset == offset);
 989    }
 990    {
 991       GLuint istextureOffset = _glapi_get_proc_offset("glIsTextureEXT");
 992       char *istextureFunc = (char*) &table->IsTextureEXT;
 993       GLuint offset = (istextureFunc - (char *) table) / sizeof(void *);
 994       assert(istextureOffset == _gloffset_IsTextureEXT);
 995       assert(istextureOffset == offset);
 996    }
 997    {
 998       GLuint secondaryColor3fOffset = _glapi_get_proc_offset("glSecondaryColor3fEXT");
 999       char *secondaryColor3fFunc = (char*) &table->SecondaryColor3fEXT;
1000       GLuint offset = (secondaryColor3fFunc - (char *) table) / sizeof(void *);
1001       assert(secondaryColor3fOffset == _gloffset_SecondaryColor3fEXT);
1002       assert(secondaryColor3fOffset == offset);
1003       assert(_glapi_get_proc_address("glSecondaryColor3fEXT") == (_glapi_proc) &glSecondaryColor3fEXT);
1004    }
1005    {
1006       GLuint pointParameterivOffset = _glapi_get_proc_offset("glPointParameterivNV");
1007       char *pointParameterivFunc = (char*) &table->PointParameterivNV;
1008       GLuint offset = (pointParameterivFunc - (char *) table) / sizeof(void *);
1009       assert(pointParameterivOffset == _gloffset_PointParameterivNV);
1010       assert(pointParameterivOffset == offset);
1011       assert(_glapi_get_proc_address("glPointParameterivNV") == (_glapi_proc) &glPointParameterivNV);
1012    }
1013    {
1014       GLuint setFenceOffset = _glapi_get_proc_offset("glSetFenceNV");
1015       char *setFenceFunc = (char*) &table->SetFenceNV;
1016       GLuint offset = (setFenceFunc - (char *) table) / sizeof(void *);
1017       assert(setFenceOffset == _gloffset_SetFenceNV);
1018       assert(setFenceOffset == offset);
1019       assert(_glapi_get_proc_address("glSetFenceNV") == (_glapi_proc) &glSetFenceNV);
1020    }
1021 #else
1022    (void) table;
1023 #endif
1024 }
1025
1026
1027 #if defined(PTHREADS) || defined(GLX_USE_TLS)
1028 /**
1029  * Perform platform-specific GL API entry-point fixups.
1030  *
1031  *
1032  */
1033 static void
1034 init_glapi_relocs( void )
1035 {
1036 #if defined( USE_X86_ASM ) && defined( GLX_USE_TLS )
1037     extern void * _x86_get_dispatch(void);
1038     const GLubyte * const get_disp = (const GLubyte *) _x86_get_dispatch;
1039     GLubyte * curr_func = (GLubyte *) gl_dispatch_functions_start;
1040
1041
1042     while ( curr_func != (GLubyte *) gl_dispatch_functions_end ) {
1043         (void) memcpy( curr_func, get_disp, 6 );
1044         curr_func += X86_DISPATCH_FUNCTION_SIZE;
1045     }
1046 #endif /* defined( USE_X86_ASM ) && defined( GLX_USE_TLS ) */
1047 }
1048 #endif