src/mesa/drivers/dri/common/xmlconfig.c

   1 /*
   2  * XML DRI client-side driver configuration
   3  * Copyright (C) 2003 Felix Kuehling
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included
  13  * in all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  16  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * FELIX KUEHLING, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM,
  19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  20  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
  21  * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  22  *
  23  */
  24 /**
  25  * \file xmlconfig.c
  26  * \brief Driver-independent client-side part of the XML configuration
  27  * \author Felix Kuehling
  28  */
  29
  30 #include "glheader.h"
  31
  32 #include <string.h>
  33 #include <assert.h>
  34 #include <expat.h>
  35 #include <fcntl.h>
  36 #include <unistd.h>
  37 #include <errno.h>
  38 #include "imports.h"
  39 #include "dri_util.h"
  40 #include "xmlconfig.h"
  41
  42 /*
  43  * OS dependent ways of getting the name of the running program
  44  */
  45 #if (defined(__unix__) || defined(unix)) && !defined(USG)
  46 #include <sys/param.h>
  47 #endif
  48
  49 #undef GET_PROGRAM_NAME
  50
  51 #if (defined(__GNU_LIBRARY__) || defined(__GLIBC__)) && !defined(__UCLIBC__)
  52 #    if !defined(__GLIBC__) || (__GLIBC__ < 2)
  53 /* These aren't declared in any libc5 header */
  54 extern char *program_invocation_name, *program_invocation_short_name;
  55 #    endif
  56 #    define GET_PROGRAM_NAME() program_invocation_short_name
  57 #elif defined(__FreeBSD__) && (__FreeBSD__ >= 2)
  58 #    include <osreldate.h>
  59 #    if (__FreeBSD_version >= 440000)
  60 #        include <stdlib.h>
  61 #        define GET_PROGRAM_NAME() getprogname()
  62 #    endif
  63 #elif defined(__NetBSD__) && defined(__NetBSD_Version) && (__NetBSD_Version >= 106000100)
  64 #    include <stdlib.h>
  65 #    define GET_PROGRAM_NAME() getprogname()
  66 #elif defined(__sun)
  67 /* Solaris has getexecname() which returns the full path - return just
  68    the basename to match BSD getprogname() */
  69 #    include <stdlib.h>
  70 #    include <libgen.h>
  71 #    define GET_PROGRAM_NAME() basename(getexecname())
  72 #endif
  73
  74 #if !defined(GET_PROGRAM_NAME)
  75 #    if defined(OpenBSD) || defined(NetBSD) || defined(__UCLIBC__)
  76 /* This is a hack. It's said to work on OpenBSD, NetBSD and GNU.
  77  * Rogelio M.Serrano Jr. reported it's also working with UCLIBC. It's
  78  * used as a last resort, if there is no documented facility available. */
  79 static const char *__getProgramName () {
  80     extern const char *__progname;
  81     char * arg = strrchr(__progname, '/');
  82     if (arg)
  83         return arg+1;
  84     else
  85         return __progname;
  86 }
  87 #        define GET_PROGRAM_NAME() __getProgramName()
  88 #    else
  89 #        define GET_PROGRAM_NAME() ""
  90 #        warning "Per application configuration won't work with your OS version."
  91 #    endif
  92 #endif
  93
  94 /** \brief Find an option in an option cache with the name as key */
  95 static GLuint findOption (const driOptionCache *cache, const char *name) {
  96     GLuint len = strlen (name);
  97     GLuint size = 1 << cache->tableSize, mask = size - 1;
  98     GLuint hash = 0;
  99     GLuint i, shift;
 100
 101   /* compute a hash from the variable length name */
 102     for (i = 0, shift = 0; i < len; ++i, shift = (shift+8) & 31)
 103         hash += (GLuint)name[i] << shift;
 104     hash *= hash;
 105     hash = (hash >> (16-cache->tableSize/2)) & mask;
 106
 107   /* this is just the starting point of the linear search for the option */
 108     for (i = 0; i < size; ++i, hash = (hash+1) & mask) {
 109       /* if we hit an empty entry then the option is not defined (yet) */
 110         if (cache->info[hash].name == 0)
 111             break;
 112         else if (!strcmp (name, cache->info[hash].name))
 113             break;
 114     }
 115   /* this assertion fails if the hash table is full */
 116     assert (i < size);
 117
 118     return hash;
 119 }
 120
 121 /** \brief Count the real number of options in an option cache */
 122 static GLuint countOptions (const driOptionCache *cache) {
 123     GLuint size = 1 << cache->tableSize;
 124     GLuint i, count = 0;
 125     for (i = 0; i < size; ++i)
 126         if (cache->info[i].name)
 127             count++;
 128     return count;
 129 }
 130
 131 /** \brief Like strdup but using MALLOC and with error checking. */
 132 #define XSTRDUP(dest,source) do { \
 133     GLuint len = strlen (source); \
 134     if (!(dest = MALLOC (len+1))) { \
 135         fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__); \
 136         abort(); \
 137     } \
 138     memcpy (dest, source, len+1); \
 139 } while (0)
 140
 141 static int compare (const void *a, const void *b) {
 142     return strcmp (*(char *const*)a, *(char *const*)b);
 143 }
 144 /** \brief Binary search in a string array. */
 145 static GLuint bsearchStr (const XML_Char *name,
 146                           const XML_Char *elems[], GLuint count) {
 147     const XML_Char **found;
 148     found = bsearch (&name, elems, count, sizeof (XML_Char *), compare);
 149     if (found)
 150         return found - elems;
 151     else
 152         return count;
 153 }
 154
 155 /** \brief Locale-independent integer parser.
 156  *
 157  * Works similar to strtol. Leading space is NOT skipped. The input
 158  * number may have an optional sign. Radix is specified by base. If
 159  * base is 0 then decimal is assumed unless the input number is
 160  * prefixed by 0x or 0X for hexadecimal or 0 for octal. After
 161  * returning tail points to the first character that is not part of
 162  * the integer number. If no number was found then tail points to the
 163  * start of the input string. */
 164 static GLint strToI (const XML_Char *string, const XML_Char **tail, int base) {
 165     GLint radix = base == 0 ? 10 : base;
 166     GLint result = 0;
 167     GLint sign = 1;
 168     GLboolean numberFound = GL_FALSE;
 169     const XML_Char *start = string;
 170
 171     assert (radix >= 2 && radix <= 36);
 172
 173     if (*string == '-') {
 174         sign = -1;
 175         string++;
 176     } else if (*string == '+')
 177         string++;
 178     if (base == 0 && *string == '0') {
 179         numberFound = GL_TRUE;
 180         if (*(string+1) == 'x' || *(string+1) == 'X') {
 181             radix = 16;
 182             string += 2;
 183         } else {
 184             radix = 8;
 185             string++;
 186         }
 187     }
 188     do {
 189         GLint digit = -1;
 190         if (radix <= 10) {
 191             if (*string >= '0' && *string < '0' + radix)
 192                 digit = *string - '0';
 193         } else {
 194             if (*string >= '0' && *string <= '9')
 195                 digit = *string - '0';
 196             else if (*string >= 'a' && *string < 'a' + radix - 10)
 197                 digit = *string - 'a' + 10;
 198             else if (*string >= 'A' && *string < 'A' + radix - 10)
 199                 digit = *string - 'A' + 10;
 200         }
 201         if (digit != -1) {
 202             numberFound = GL_TRUE;
 203             result = radix*result + digit;
 204             string++;
 205         } else
 206             break;
 207     } while (GL_TRUE);
 208     *tail = numberFound ? string : start;
 209     return sign * result;
 210 }
 211
 212 /** \brief Locale-independent floating-point parser.
 213  *
 214  * Works similar to strtod. Leading space is NOT skipped. The input
 215  * number may have an optional sign. '.' is interpreted as decimal
 216  * point and may occor at most once. Optionally the number may end in
 217  * [eE]<exponent>, where <exponent> is an integer as recognized by
 218  * strToI. In that case the result is number * 10^exponent. After
 219  * returning tail points to the first character that is not part of
 220  * the floating point number. If no number was found then tail points
 221  * to the start of the input string.
 222  *
 223  * Uses two passes for maximum accuracy. */
 224 static GLfloat strToF (const XML_Char *string, const XML_Char **tail) {
 225     GLint nDigits = 0, pointPos, exponent;
 226     GLfloat sign = 1.0f, result = 0.0f, scale;
 227     const XML_Char *start = string, *numStart;
 228
 229     /* sign */
 230     if (*string == '-') {
 231         sign = -1.0f;
 232         string++;
 233     } else if (*string == '+')
 234         string++;
 235
 236     /* first pass: determine position of decimal point, number of
 237      * digits, exponent and the end of the number. */
 238     numStart = string;
 239     while (*string >= '0' && *string <= '9') {
 240         string++;
 241         nDigits++;
 242     }
 243     pointPos = nDigits;
 244     if (*string == '.') {
 245         string++;
 246         while (*string >= '0' && *string <= '9') {
 247             string++;
 248             nDigits++;
 249         }
 250     }
 251     if (nDigits == 0) {
 252         /* no digits, no number */
 253         *tail = start;
 254         return 0.0f;
 255     }
 256     *tail = string;
 257     if (*string == 'e' || *string == 'E') {
 258         const XML_Char *expTail;
 259         exponent = strToI (string+1, &expTail, 10);
 260         if (expTail == string+1)
 261             exponent = 0;
 262         else
 263             *tail = expTail;
 264     } else
 265         exponent = 0;
 266     string = numStart;
 267
 268     /* scale of the first digit */
 269     scale = sign * (GLfloat)pow (10.0, (GLdouble)(pointPos-1 + exponent));
 270
 271     /* second pass: parse digits */
 272     do {
 273         if (*string != '.') {
 274             assert (*string >= '0' && *string <= '9');
 275             result += scale * (GLfloat)(*string - '0');
 276             scale *= 0.1f;
 277             nDigits--;
 278         }
 279         string++;
 280     } while (nDigits > 0);
 281
 282     return result;
 283 }
 284
 285 /** \brief Parse a value of a given type. */
 286 static GLboolean parseValue (driOptionValue *v, driOptionType type,
 287                              const XML_Char *string) {
 288     const XML_Char *tail = NULL;
 289   /* skip leading white-space */
 290     string += strspn (string, " \f\n\r\t\v");
 291     switch (type) {
 292       case DRI_BOOL:
 293         if (!strcmp (string, "false")) {
 294             v->_bool = GL_FALSE;
 295             tail = string + 5;
 296         } else if (!strcmp (string, "true")) {
 297             v->_bool = GL_TRUE;
 298             tail = string + 4;
 299         }
 300         else
 301             return GL_FALSE;
 302         break;
 303       case DRI_ENUM: /* enum is just a special integer */
 304       case DRI_INT:
 305         v->_int = strToI (string, &tail, 0);
 306         break;
 307       case DRI_FLOAT:
 308         v->_float = strToF (string, &tail);
 309         break;
 310     }
 311
 312     if (tail == string)
 313         return GL_FALSE; /* empty string (or containing only white-space) */
 314   /* skip trailing white space */
 315     if (*tail)
 316         tail += strspn (tail, " \f\n\r\t\v");
 317     if (*tail)
 318         return GL_FALSE; /* something left over that is not part of value */
 319
 320     return GL_TRUE;
 321 }
 322
 323 /** \brief Parse a list of ranges of type info->type. */
 324 static GLboolean parseRanges (driOptionInfo *info, const XML_Char *string) {
 325     XML_Char *cp, *range;
 326     GLuint nRanges, i;
 327     driOptionRange *ranges;
 328
 329     XSTRDUP (cp, string);
 330   /* pass 1: determine the number of ranges (number of commas + 1) */
 331     range = cp;
 332     for (nRanges = 1; *range; ++range)
 333         if (*range == ',')
 334             ++nRanges;
 335
 336     if ((ranges = MALLOC (nRanges*sizeof(driOptionRange))) == NULL) {
 337         fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
 338         abort();
 339     }
 340
 341   /* pass 2: parse all ranges into preallocated array */
 342     range = cp;
 343     for (i = 0; i < nRanges; ++i) {
 344         XML_Char *end, *sep;
 345         assert (range);
 346         end = strchr (range, ',');
 347         if (end)
 348             *end = '\0';
 349         sep = strchr (range, ':');
 350         if (sep) { /* non-empty interval */
 351             *sep = '\0';
 352             if (!parseValue (&ranges[i].start, info->type, range) ||
 353                 !parseValue (&ranges[i].end, info->type, sep+1))
 354                 break;
 355             if (info->type == DRI_INT &&
 356                 ranges[i].start._int > ranges[i].end._int)
 357                 break;
 358             if (info->type == DRI_FLOAT &&
 359                 ranges[i].start._float > ranges[i].end._float)
 360                 break;
 361         } else { /* empty interval */
 362             if (!parseValue (&ranges[i].start, info->type, range))
 363                 break;
 364             ranges[i].end = ranges[i].start;
 365         }
 366         if (end)
 367             range = end+1;
 368         else
 369             range = NULL;
 370     }
 371     FREE (cp);
 372     if (i < nRanges) {
 373         FREE (ranges);
 374         return GL_FALSE;
 375     } else
 376         assert (range == NULL);
 377
 378     info->nRanges = nRanges;
 379     info->ranges = ranges;
 380     return GL_TRUE;
 381 }
 382
 383 /** \brief Check if a value is in one of info->ranges. */
 384 static GLboolean checkValue (const driOptionValue *v, const driOptionInfo *info) {
 385     GLuint i;
 386     assert (info->type != DRI_BOOL); /* should be caught by the parser */
 387     if (info->nRanges == 0)
 388         return GL_TRUE;
 389     switch (info->type) {
 390       case DRI_ENUM: /* enum is just a special integer */
 391       case DRI_INT:
 392         for (i = 0; i < info->nRanges; ++i)
 393             if (v->_int >= info->ranges[i].start._int &&
 394                 v->_int <= info->ranges[i].end._int)
 395                 return GL_TRUE;
 396         break;
 397       case DRI_FLOAT:
 398         for (i = 0; i < info->nRanges; ++i)
 399             if (v->_float >= info->ranges[i].start._float &&
 400                 v->_float <= info->ranges[i].end._float)
 401                 return GL_TRUE;
 402         break;
 403       default:
 404         assert (0); /* should never happen */
 405     }
 406     return GL_FALSE;
 407 }
 408
 409 /** \brief Output a warning message. */
 410 #define XML_WARNING1(msg) do {\
 411     __driUtilMessage ("Warning in %s line %d, column %d: "msg, data->name, \
 412                       (int) XML_GetCurrentLineNumber(data->parser), \
 413                       (int) XML_GetCurrentColumnNumber(data->parser)); \
 414 } while (0)
 415 #define XML_WARNING(msg,args...) do { \
 416     __driUtilMessage ("Warning in %s line %d, column %d: "msg, data->name, \
 417                       (int) XML_GetCurrentLineNumber(data->parser), \
 418                       (int) XML_GetCurrentColumnNumber(data->parser), \
 419                       args); \
 420 } while (0)
 421 /** \brief Output an error message. */
 422 #define XML_ERROR1(msg) do { \
 423     __driUtilMessage ("Error in %s line %d, column %d: "msg, data->name, \
 424                       (int) XML_GetCurrentLineNumber(data->parser), \
 425                       (int) XML_GetCurrentColumnNumber(data->parser)); \
 426 } while (0)
 427 #define XML_ERROR(msg,args...) do { \
 428     __driUtilMessage ("Error in %s line %d, column %d: "msg, data->name, \
 429                       (int) XML_GetCurrentLineNumber(data->parser), \
 430                       (int) XML_GetCurrentColumnNumber(data->parser), \
 431                       args); \
 432 } while (0)
 433 /** \brief Output a fatal error message and abort. */
 434 #define XML_FATAL1(msg) do { \
 435     fprintf (stderr, "Fatal error in %s line %d, column %d: "msg"\n", \
 436              data->name, \
 437              (int) XML_GetCurrentLineNumber(data->parser),      \
 438              (int) XML_GetCurrentColumnNumber(data->parser)); \
 439     abort();\
 440 } while (0)
 441 #define XML_FATAL(msg,args...) do { \
 442     fprintf (stderr, "Fatal error in %s line %d, column %d: "msg"\n", \
 443              data->name, \
 444              (int) XML_GetCurrentLineNumber(data->parser),      \
 445              (int) XML_GetCurrentColumnNumber(data->parser),            \
 446              args); \
 447     abort();\
 448 } while (0)
 449
 450 /** \brief Parser context for __driConfigOptions. */
 451 struct OptInfoData {
 452     const char *name;
 453     XML_Parser parser;
 454     driOptionCache *cache;
 455     GLboolean inDriInfo;
 456     GLboolean inSection;
 457     GLboolean inDesc;
 458     GLboolean inOption;
 459     GLboolean inEnum;
 460     int curOption;
 461 };
 462
 463 /** \brief Elements in __driConfigOptions. */
 464 enum OptInfoElem {
 465     OI_DESCRIPTION = 0, OI_DRIINFO, OI_ENUM, OI_OPTION, OI_SECTION, OI_COUNT
 466 };
 467 static const XML_Char *OptInfoElems[] = {
 468     "description", "driinfo", "enum", "option", "section"
 469 };
 470
 471 /** \brief Parse attributes of an enum element.
 472  *
 473  * We're not actually interested in the data. Just make sure this is ok
 474  * for external configuration tools.
 475  */
 476 static void parseEnumAttr (struct OptInfoData *data, const XML_Char **attr) {
 477     GLuint i;
 478     const XML_Char *value = NULL, *text = NULL;
 479     driOptionValue v;
 480     GLuint opt = data->curOption;
 481     for (i = 0; attr[i]; i += 2) {
 482         if (!strcmp (attr[i], "value")) value = attr[i+1];
 483         else if (!strcmp (attr[i], "text")) text = attr[i+1];
 484         else XML_FATAL("illegal enum attribute: %s.", attr[i]);
 485     }
 486     if (!value) XML_FATAL1 ("value attribute missing in enum.");
 487     if (!text) XML_FATAL1 ("text attribute missing in enum.");
 488      if (!parseValue (&v, data->cache->info[opt].type, value))
 489         XML_FATAL ("illegal enum value: %s.", value);
 490     if (!checkValue (&v, &data->cache->info[opt]))
 491         XML_FATAL ("enum value out of valid range: %s.", value);
 492 }
 493
 494 /** \brief Parse attributes of a description element.
 495  *
 496  * We're not actually interested in the data. Just make sure this is ok
 497  * for external configuration tools.
 498  */
 499 static void parseDescAttr (struct OptInfoData *data, const XML_Char **attr) {
 500     GLuint i;
 501     const XML_Char *lang = NULL, *text = NULL;
 502     for (i = 0; attr[i]; i += 2) {
 503         if (!strcmp (attr[i], "lang")) lang = attr[i+1];
 504         else if (!strcmp (attr[i], "text")) text = attr[i+1];
 505         else XML_FATAL("illegal description attribute: %s.", attr[i]);
 506     }
 507     if (!lang) XML_FATAL1 ("lang attribute missing in description.");
 508     if (!text) XML_FATAL1 ("text attribute missing in description.");
 509 }
 510
 511 /** \brief Parse attributes of an option element. */
 512 static void parseOptInfoAttr (struct OptInfoData *data, const XML_Char **attr) {
 513     enum OptAttr {OA_DEFAULT = 0, OA_NAME, OA_TYPE, OA_VALID, OA_COUNT};
 514     static const XML_Char *optAttr[] = {"default", "name", "type", "valid"};
 515     const XML_Char *attrVal[OA_COUNT] = {NULL, NULL, NULL, NULL};
 516     const char *defaultVal;
 517     driOptionCache *cache = data->cache;
 518     GLuint opt, i;
 519     for (i = 0; attr[i]; i += 2) {
 520         GLuint attrName = bsearchStr (attr[i], optAttr, OA_COUNT);
 521         if (attrName >= OA_COUNT)
 522             XML_FATAL ("illegal option attribute: %s", attr[i]);
 523         attrVal[attrName] = attr[i+1];
 524     }
 525     if (!attrVal[OA_NAME]) XML_FATAL1 ("name attribute missing in option.");
 526     if (!attrVal[OA_TYPE]) XML_FATAL1 ("type attribute missing in option.");
 527     if (!attrVal[OA_DEFAULT]) XML_FATAL1 ("default attribute missing in option.");
 528
 529     opt = findOption (cache, attrVal[OA_NAME]);
 530     if (cache->info[opt].name)
 531         XML_FATAL ("option %s redefined.", attrVal[OA_NAME]);
 532     data->curOption = opt;
 533
 534     XSTRDUP (cache->info[opt].name, attrVal[OA_NAME]);
 535
 536     if (!strcmp (attrVal[OA_TYPE], "bool"))
 537         cache->info[opt].type = DRI_BOOL;
 538     else if (!strcmp (attrVal[OA_TYPE], "enum"))
 539         cache->info[opt].type = DRI_ENUM;
 540     else if (!strcmp (attrVal[OA_TYPE], "int"))
 541         cache->info[opt].type = DRI_INT;
 542     else if (!strcmp (attrVal[OA_TYPE], "float"))
 543         cache->info[opt].type = DRI_FLOAT;
 544     else
 545         XML_FATAL ("illegal type in option: %s.", attrVal[OA_TYPE]);
 546
 547     defaultVal = getenv (cache->info[opt].name);
 548     if (defaultVal != NULL) {
 549       /* don't use XML_WARNING, we want the user to see this! */
 550         fprintf (stderr,
 551                  "ATTENTION: default value of option %s overridden by environment.\n",
 552                  cache->info[opt].name);
 553     } else
 554         defaultVal = attrVal[OA_DEFAULT];
 555     if (!parseValue (&cache->values[opt], cache->info[opt].type, defaultVal))
 556         XML_FATAL ("illegal default value: %s.", defaultVal);
 557
 558     if (attrVal[OA_VALID]) {
 559         if (cache->info[opt].type == DRI_BOOL)
 560             XML_FATAL1 ("boolean option with valid attribute.");
 561         if (!parseRanges (&cache->info[opt], attrVal[OA_VALID]))
 562             XML_FATAL ("illegal valid attribute: %s.", attrVal[OA_VALID]);
 563         if (!checkValue (&cache->values[opt], &cache->info[opt]))
 564             XML_FATAL ("default value out of valid range '%s': %s.",
 565                        attrVal[OA_VALID], defaultVal);
 566     } else if (cache->info[opt].type == DRI_ENUM) {
 567         XML_FATAL1 ("valid attribute missing in option (mandatory for enums).");
 568     } else {
 569         cache->info[opt].nRanges = 0;
 570         cache->info[opt].ranges = NULL;
 571     }
 572 }
 573
 574 /** \brief Handler for start element events. */
 575 static void optInfoStartElem (void *userData, const XML_Char *name,
 576                               const XML_Char **attr) {
 577     struct OptInfoData *data = (struct OptInfoData *)userData;
 578     enum OptInfoElem elem = bsearchStr (name, OptInfoElems, OI_COUNT);
 579     switch (elem) {
 580       case OI_DRIINFO:
 581         if (data->inDriInfo)
 582             XML_FATAL1 ("nested <driinfo> elements.");
 583         if (attr[0])
 584             XML_FATAL1 ("attributes specified on <driinfo> element.");
 585         data->inDriInfo = GL_TRUE;
 586         break;
 587       case OI_SECTION:
 588         if (!data->inDriInfo)
 589             XML_FATAL1 ("<section> must be inside <driinfo>.");
 590         if (data->inSection)
 591             XML_FATAL1 ("nested <section> elements.");
 592         if (attr[0])
 593             XML_FATAL1 ("attributes specified on <section> element.");
 594         data->inSection = GL_TRUE;
 595         break;
 596       case OI_DESCRIPTION:
 597         if (!data->inSection && !data->inOption)
 598             XML_FATAL1 ("<description> must be inside <description> or <option.");
 599         if (data->inDesc)
 600             XML_FATAL1 ("nested <description> elements.");
 601         data->inDesc = GL_TRUE;
 602         parseDescAttr (data, attr);
 603         break;
 604       case OI_OPTION:
 605         if (!data->inSection)
 606             XML_FATAL1 ("<option> must be inside <section>.");
 607         if (data->inDesc)
 608             XML_FATAL1 ("<option> nested in <description> element.");
 609         if (data->inOption)
 610             XML_FATAL1 ("nested <option> elements.");
 611         data->inOption = GL_TRUE;
 612         parseOptInfoAttr (data, attr);
 613         break;
 614       case OI_ENUM:
 615         if (!(data->inOption && data->inDesc))
 616             XML_FATAL1 ("<enum> must be inside <option> and <description>.");
 617         if (data->inEnum)
 618             XML_FATAL1 ("nested <enum> elements.");
 619         data->inEnum = GL_TRUE;
 620         parseEnumAttr (data, attr);
 621         break;
 622       default:
 623         XML_FATAL ("unknown element: %s.", name);
 624     }
 625 }
 626
 627 /** \brief Handler for end element events. */
 628 static void optInfoEndElem (void *userData, const XML_Char *name) {
 629     struct OptInfoData *data = (struct OptInfoData *)userData;
 630     enum OptInfoElem elem = bsearchStr (name, OptInfoElems, OI_COUNT);
 631     switch (elem) {
 632       case OI_DRIINFO:
 633         data->inDriInfo = GL_FALSE;
 634         break;
 635       case OI_SECTION:
 636         data->inSection = GL_FALSE;
 637         break;
 638       case OI_DESCRIPTION:
 639         data->inDesc = GL_FALSE;
 640         break;
 641       case OI_OPTION:
 642         data->inOption = GL_FALSE;
 643         break;
 644       case OI_ENUM:
 645         data->inEnum = GL_FALSE;
 646         break;
 647       default:
 648         assert (0); /* should have been caught by StartElem */
 649     }
 650 }
 651
 652 void driParseOptionInfo (driOptionCache *info,
 653                          const char *configOptions, GLuint nConfigOptions) {
 654     XML_Parser p;
 655     int status;
 656     struct OptInfoData userData;
 657     struct OptInfoData *data = &userData;
 658     GLuint realNoptions;
 659
 660   /* determine hash table size and allocate memory:
 661    * 3/2 of the number of options, rounded up, so there remains always
 662    * at least one free entry. This is needed for detecting undefined
 663    * options in configuration files without getting a hash table overflow.
 664    * Round this up to a power of two. */
 665     GLuint minSize = (nConfigOptions*3 + 1) / 2;
 666     GLuint size, log2size;
 667     for (size = 1, log2size = 0; size < minSize; size <<= 1, ++log2size);
 668     info->tableSize = log2size;
 669     info->info = CALLOC (size * sizeof (driOptionInfo));
 670     info->values = CALLOC (size * sizeof (driOptionValue));
 671     if (info->info == NULL || info->values == NULL) {
 672         fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
 673         abort();
 674     }
 675
 676     p = XML_ParserCreate ("UTF-8"); /* always UTF-8 */
 677     XML_SetElementHandler (p, optInfoStartElem, optInfoEndElem);
 678     XML_SetUserData (p, data);
 679
 680     userData.name = "__driConfigOptions";
 681     userData.parser = p;
 682     userData.cache = info;
 683     userData.inDriInfo = GL_FALSE;
 684     userData.inSection = GL_FALSE;
 685     userData.inDesc = GL_FALSE;
 686     userData.inOption = GL_FALSE;
 687     userData.inEnum = GL_FALSE;
 688     userData.curOption = -1;
 689
 690     status = XML_Parse (p, configOptions, strlen (configOptions), 1);
 691     if (!status)
 692         XML_FATAL ("%s.", XML_ErrorString(XML_GetErrorCode(p)));
 693
 694     XML_ParserFree (p);
 695
 696   /* Check if the actual number of options matches nConfigOptions.
 697    * A mismatch is not fatal (a hash table overflow would be) but we
 698    * want the driver developer's attention anyway. */
 699     realNoptions = countOptions (info);
 700     if (realNoptions != nConfigOptions) {
 701         fprintf (stderr,
 702                  "Error: nConfigOptions (%u) does not match the actual number of options in\n"
 703                  "       __driConfigOptions (%u).\n",
 704                  nConfigOptions, realNoptions);
 705     }
 706 }
 707
 708 /** \brief Parser context for configuration files. */
 709 struct OptConfData {
 710     const char *name;
 711     XML_Parser parser;
 712     driOptionCache *cache;
 713     GLint screenNum;
 714     const char *driverName, *execName;
 715     GLuint ignoringDevice;
 716     GLuint ignoringApp;
 717     GLuint inDriConf;
 718     GLuint inDevice;
 719     GLuint inApp;
 720     GLuint inOption;
 721 };
 722
 723 /** \brief Elements in configuration files. */
 724 enum OptConfElem {
 725     OC_APPLICATION = 0, OC_DEVICE, OC_DRICONF, OC_OPTION, OC_COUNT
 726 };
 727 static const XML_Char *OptConfElems[] = {
 728     "application", "device", "driconf", "option"
 729 };
 730
 731 /** \brief Parse attributes of a device element. */
 732 static void parseDeviceAttr (struct OptConfData *data, const XML_Char **attr) {
 733     GLuint i;
 734     const XML_Char *driver = NULL, *screen = NULL;
 735     for (i = 0; attr[i]; i += 2) {
 736         if (!strcmp (attr[i], "driver")) driver = attr[i+1];
 737         else if (!strcmp (attr[i], "screen")) screen = attr[i+1];
 738         else XML_WARNING("unkown device attribute: %s.", attr[i]);
 739     }
 740     if (driver && strcmp (driver, data->driverName))
 741         data->ignoringDevice = data->inDevice;
 742     else if (screen) {
 743         driOptionValue screenNum;
 744         if (!parseValue (&screenNum, DRI_INT, screen))
 745             XML_WARNING("illegal screen number: %s.", screen);
 746         else if (screenNum._int != data->screenNum)
 747             data->ignoringDevice = data->inDevice;
 748     }
 749 }
 750
 751 /** \brief Parse attributes of an application element. */
 752 static void parseAppAttr (struct OptConfData *data, const XML_Char **attr) {
 753     GLuint i;
 754     const XML_Char *name = NULL, *exec = NULL;
 755     for (i = 0; attr[i]; i += 2) {
 756         if (!strcmp (attr[i], "name")) name = attr[i+1];
 757         else if (!strcmp (attr[i], "executable")) exec = attr[i+1];
 758         else XML_WARNING("unkown application attribute: %s.", attr[i]);
 759     }
 760     if (exec && strcmp (exec, data->execName))
 761         data->ignoringApp = data->inApp;
 762 }
 763
 764 /** \brief Parse attributes of an option element. */
 765 static void parseOptConfAttr (struct OptConfData *data, const XML_Char **attr) {
 766     GLuint i;
 767     const XML_Char *name = NULL, *value = NULL;
 768     for (i = 0; attr[i]; i += 2) {
 769         if (!strcmp (attr[i], "name")) name = attr[i+1];
 770         else if (!strcmp (attr[i], "value")) value = attr[i+1];
 771         else XML_WARNING("unkown option attribute: %s.", attr[i]);
 772     }
 773     if (!name) XML_WARNING1 ("name attribute missing in option.");
 774     if (!value) XML_WARNING1 ("value attribute missing in option.");
 775     if (name && value) {
 776         driOptionCache *cache = data->cache;
 777         GLuint opt = findOption (cache, name);
 778         if (cache->info[opt].name == NULL)
 779             XML_WARNING ("undefined option: %s.", name);
 780         else if (getenv (cache->info[opt].name))
 781           /* don't use XML_WARNING, we want the user to see this! */
 782             fprintf (stderr, "ATTENTION: option value of option %s ignored.\n",
 783                      cache->info[opt].name);
 784         else if (!parseValue (&cache->values[opt], cache->info[opt].type, value))
 785             XML_WARNING ("illegal option value: %s.", value);
 786     }
 787 }
 788
 789 /** \brief Handler for start element events. */
 790 static void optConfStartElem (void *userData, const XML_Char *name,
 791                               const XML_Char **attr) {
 792     struct OptConfData *data = (struct OptConfData *)userData;
 793     enum OptConfElem elem = bsearchStr (name, OptConfElems, OC_COUNT);
 794     switch (elem) {
 795       case OC_DRICONF:
 796         if (data->inDriConf)
 797             XML_WARNING1 ("nested <driconf> elements.");
 798         if (attr[0])
 799             XML_WARNING1 ("attributes specified on <driconf> element.");
 800         data->inDriConf++;
 801         break;
 802       case OC_DEVICE:
 803         if (!data->inDriConf)
 804             XML_WARNING1 ("<device> should be inside <driconf>.");
 805         if (data->inDevice)
 806             XML_WARNING1 ("nested <device> elements.");
 807         data->inDevice++;
 808         if (!data->ignoringDevice && !data->ignoringApp)
 809             parseDeviceAttr (data, attr);
 810         break;
 811       case OC_APPLICATION:
 812         if (!data->inDevice)
 813             XML_WARNING1 ("<application> should be inside <device>.");
 814         if (data->inApp)
 815             XML_WARNING1 ("nested <application> elements.");
 816         data->inApp++;
 817         if (!data->ignoringDevice && !data->ignoringApp)
 818             parseAppAttr (data, attr);
 819         break;
 820       case OC_OPTION:
 821         if (!data->inApp)
 822             XML_WARNING1 ("<option> should be inside <application>.");
 823         if (data->inOption)
 824             XML_WARNING1 ("nested <option> elements.");
 825         data->inOption++;
 826         if (!data->ignoringDevice && !data->ignoringApp)
 827             parseOptConfAttr (data, attr);
 828         break;
 829       default:
 830         XML_WARNING ("unknown element: %s.", name);
 831     }
 832 }
 833
 834 /** \brief Handler for end element events. */
 835 static void optConfEndElem (void *userData, const XML_Char *name) {
 836     struct OptConfData *data = (struct OptConfData *)userData;
 837     enum OptConfElem elem = bsearchStr (name, OptConfElems, OC_COUNT);
 838     switch (elem) {
 839       case OC_DRICONF:
 840         data->inDriConf--;
 841         break;
 842       case OC_DEVICE:
 843         if (data->inDevice-- == data->ignoringDevice)
 844             data->ignoringDevice = 0;
 845         break;
 846       case OC_APPLICATION:
 847         if (data->inApp-- == data->ignoringApp)
 848             data->ignoringApp = 0;
 849         break;
 850       case OC_OPTION:
 851         data->inOption--;
 852         break;
 853       default:
 854         /* unknown element, warning was produced on start tag */;
 855     }
 856 }
 857
 858 /** \brief Initialize an option cache based on info */
 859 static void initOptionCache (driOptionCache *cache, const driOptionCache *info) {
 860     cache->info = info->info;
 861     cache->tableSize = info->tableSize;
 862     cache->values = MALLOC ((1<<info->tableSize) * sizeof (driOptionValue));
 863     if (cache->values == NULL) {
 864         fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
 865         abort();
 866     }
 867     memcpy (cache->values, info->values,
 868             (1<<info->tableSize) * sizeof (driOptionValue));
 869 }
 870
 871 /** \brief Parse the named configuration file */
 872 static void parseOneConfigFile (XML_Parser p) {
 873 #define BUF_SIZE 0x1000
 874     struct OptConfData *data = (struct OptConfData *)XML_GetUserData (p);
 875     int status;
 876     int fd;
 877
 878     if ((fd = open (data->name, O_RDONLY)) == -1) {
 879         __driUtilMessage ("Can't open configuration file %s: %s.",
 880                           data->name, strerror (errno));
 881         return;
 882     }
 883
 884     while (1) {
 885         int bytesRead;
 886         void *buffer = XML_GetBuffer (p, BUF_SIZE);
 887         if (!buffer) {
 888             __driUtilMessage ("Can't allocate parser buffer.");
 889             break;
 890         }
 891         bytesRead = read (fd, buffer, BUF_SIZE);
 892         if (bytesRead == -1) {
 893             __driUtilMessage ("Error reading from configuration file %s: %s.",
 894                               data->name, strerror (errno));
 895             break;
 896         }
 897         status = XML_ParseBuffer (p, bytesRead, bytesRead == 0);
 898         if (!status) {
 899             XML_ERROR ("%s.", XML_ErrorString(XML_GetErrorCode(p)));
 900             break;
 901         }
 902         if (bytesRead == 0)
 903             break;
 904     }
 905
 906     close (fd);
 907 #undef BUF_SIZE
 908 }
 909
 910 void driParseConfigFiles (driOptionCache *cache, const driOptionCache *info,
 911                           GLint screenNum, const char *driverName) {
 912     char *filenames[2] = {"/etc/drirc", NULL};
 913     char *home;
 914     GLuint i;
 915     struct OptConfData userData;
 916
 917     initOptionCache (cache, info);
 918
 919     userData.cache = cache;
 920     userData.screenNum = screenNum;
 921     userData.driverName = driverName;
 922     userData.execName = GET_PROGRAM_NAME();
 923
 924     if ((home = getenv ("HOME"))) {
 925         GLuint len = strlen (home);
 926         filenames[1] = MALLOC (len + 7+1);
 927         if (filenames[1] == NULL)
 928             __driUtilMessage ("Can't allocate memory for %s/.drirc.", home);
 929         else {
 930             memcpy (filenames[1], home, len);
 931             memcpy (filenames[1] + len, "/.drirc", 7+1);
 932         }
 933     }
 934
 935     for (i = 0; i < 2; ++i) {
 936         XML_Parser p;
 937         if (filenames[i] == NULL)
 938             continue;
 939
 940         p = XML_ParserCreate (NULL); /* use encoding specified by file */
 941         XML_SetElementHandler (p, optConfStartElem, optConfEndElem);
 942         XML_SetUserData (p, &userData);
 943         userData.parser = p;
 944         userData.name = filenames[i];
 945         userData.ignoringDevice = 0;
 946         userData.ignoringApp = 0;
 947         userData.inDriConf = 0;
 948         userData.inDevice = 0;
 949         userData.inApp = 0;
 950         userData.inOption = 0;
 951
 952         parseOneConfigFile (p);
 953         XML_ParserFree (p);
 954     }
 955
 956     if (filenames[1])
 957         FREE (filenames[1]);
 958 }
 959
 960 void driDestroyOptionInfo (driOptionCache *info) {
 961     driDestroyOptionCache (info);
 962     if (info->info) {
 963         GLuint i, size = 1 << info->tableSize;
 964         for (i = 0; i < size; ++i) {
 965             if (info->info[i].name) {
 966                 FREE (info->info[i].name);
 967                 if (info->info[i].ranges)
 968                     FREE (info->info[i].ranges);
 969             }
 970         }
 971         FREE (info->info);
 972     }
 973 }
 974
 975 void driDestroyOptionCache (driOptionCache *cache) {
 976     if (cache->values)
 977         FREE (cache->values);
 978 }
 979
 980 GLboolean driCheckOption (const driOptionCache *cache, const char *name,
 981                           driOptionType type) {
 982     GLuint i = findOption (cache, name);
 983     return cache->info[i].name != NULL && cache->info[i].type == type;
 984 }
 985
 986 GLboolean driQueryOptionb (const driOptionCache *cache, const char *name) {
 987     GLuint i = findOption (cache, name);
 988   /* make sure the option is defined and has the correct type */
 989     assert (cache->info[i].name != NULL);
 990     assert (cache->info[i].type == DRI_BOOL);
 991     return cache->values[i]._bool;
 992 }
 993
 994 GLint driQueryOptioni (const driOptionCache *cache, const char *name) {
 995     GLuint i = findOption (cache, name);
 996   /* make sure the option is defined and has the correct type */
 997     assert (cache->info[i].name != NULL);
 998     assert (cache->info[i].type == DRI_INT || cache->info[i].type == DRI_ENUM);
 999     return cache->values[i]._int;
1000 }
1001
1002 GLfloat driQueryOptionf (const driOptionCache *cache, const char *name) {
1003     GLuint i = findOption (cache, name);
1004   /* make sure the option is defined and has the correct type */
1005     assert (cache->info[i].name != NULL);
1006     assert (cache->info[i].type == DRI_FLOAT);
1007     return cache->values[i]._float;
1008 }