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 <stdarg.h>
31#include <stdio.h>
32#include <string.h>
33#include <assert.h>
34#include <expat.h>
35#include <fcntl.h>
36#include <math.h>
37#include <unistd.h>
38#include <errno.h>
39#include "main/imports.h"
40#include "utils.h"
41#include "xmlconfig.h"
42
43#undef GET_PROGRAM_NAME
44
45#if (defined(__GNU_LIBRARY__) || defined(__GLIBC__)) && !defined(__UCLIBC__)
46#    if !defined(__GLIBC__) || (__GLIBC__ < 2)
47/* These aren't declared in any libc5 header */
48extern char *program_invocation_name, *program_invocation_short_name;
49#    endif
50#    define GET_PROGRAM_NAME() program_invocation_short_name
51#elif defined(__CYGWIN__)
52#    define GET_PROGRAM_NAME() program_invocation_short_name
53#elif defined(__FreeBSD__) && (__FreeBSD__ >= 2)
54#    include <osreldate.h>
55#    if (__FreeBSD_version >= 440000)
56#        include <stdlib.h>
57#        define GET_PROGRAM_NAME() getprogname()
58#    endif
59#elif defined(__NetBSD__) && defined(__NetBSD_Version__) && (__NetBSD_Version__ >= 106000100)
60#    include <stdlib.h>
61#    define GET_PROGRAM_NAME() getprogname()
62#elif defined(__DragonFly__)
63#    include <stdlib.h>
64#    define GET_PROGRAM_NAME() getprogname()
65#elif defined(__APPLE__)
66#    include <stdlib.h>
67#    define GET_PROGRAM_NAME() getprogname()
68#elif defined(__sun)
69/* Solaris has getexecname() which returns the full path - return just
70   the basename to match BSD getprogname() */
71#    include <stdlib.h>
72#    include <libgen.h>
73
74static const char *__getProgramName () {
75    static const char *progname;
76
77    if (progname == NULL) {
78	const char *e = getexecname();
79	if (e != NULL) {
80	    /* Have to make a copy since getexecname can return a readonly
81	       string, but basename expects to be able to modify its arg. */
82	    char *n = strdup(e);
83	    if (n != NULL) {
84		progname = basename(n);
85	    }
86	}
87    }
88    return progname;
89}
90
91#    define GET_PROGRAM_NAME() __getProgramName()
92#endif
93
94#if !defined(GET_PROGRAM_NAME)
95#    if defined(__OpenBSD__) || defined(NetBSD) || defined(__UCLIBC__) || defined(ANDROID)
96/* This is a hack. It's said to work on OpenBSD, NetBSD and GNU.
97 * Rogelio M.Serrano Jr. reported it's also working with UCLIBC. It's
98 * used as a last resort, if there is no documented facility available. */
99static const char *__getProgramName () {
100    extern const char *__progname;
101    char * arg = strrchr(__progname, '/');
102    if (arg)
103        return arg+1;
104    else
105        return __progname;
106}
107#        define GET_PROGRAM_NAME() __getProgramName()
108#    else
109#        define GET_PROGRAM_NAME() ""
110#        warning "Per application configuration won't work with your OS version."
111#    endif
112#endif
113
114/** \brief Find an option in an option cache with the name as key */
115static uint32_t findOption (const driOptionCache *cache, const char *name) {
116    uint32_t len = strlen (name);
117    uint32_t size = 1 << cache->tableSize, mask = size - 1;
118    uint32_t hash = 0;
119    uint32_t i, shift;
120
121  /* compute a hash from the variable length name */
122    for (i = 0, shift = 0; i < len; ++i, shift = (shift+8) & 31)
123	hash += (uint32_t)name[i] << shift;
124    hash *= hash;
125    hash = (hash >> (16-cache->tableSize/2)) & mask;
126
127  /* this is just the starting point of the linear search for the option */
128    for (i = 0; i < size; ++i, hash = (hash+1) & mask) {
129      /* if we hit an empty entry then the option is not defined (yet) */
130	if (cache->info[hash].name == 0)
131	    break;
132	else if (!strcmp (name, cache->info[hash].name))
133	    break;
134    }
135  /* this assertion fails if the hash table is full */
136    assert (i < size);
137
138    return hash;
139}
140
141/** \brief Like strdup but using malloc and with error checking. */
142#define XSTRDUP(dest,source) do { \
143    uint32_t len = strlen (source); \
144    if (!(dest = malloc(len+1))) { \
145	fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__); \
146	abort(); \
147    } \
148    memcpy (dest, source, len+1); \
149} while (0)
150
151static int compare (const void *a, const void *b) {
152    return strcmp (*(char *const*)a, *(char *const*)b);
153}
154/** \brief Binary search in a string array. */
155static uint32_t bsearchStr (const XML_Char *name,
156			  const XML_Char *elems[], uint32_t count) {
157    const XML_Char **found;
158    found = bsearch (&name, elems, count, sizeof (XML_Char *), compare);
159    if (found)
160	return found - elems;
161    else
162	return count;
163}
164
165/** \brief Locale-independent integer parser.
166 *
167 * Works similar to strtol. Leading space is NOT skipped. The input
168 * number may have an optional sign. Radix is specified by base. If
169 * base is 0 then decimal is assumed unless the input number is
170 * prefixed by 0x or 0X for hexadecimal or 0 for octal. After
171 * returning tail points to the first character that is not part of
172 * the integer number. If no number was found then tail points to the
173 * start of the input string. */
174static int strToI (const XML_Char *string, const XML_Char **tail, int base) {
175    int radix = base == 0 ? 10 : base;
176    int result = 0;
177    int sign = 1;
178    bool numberFound = false;
179    const XML_Char *start = string;
180
181    assert (radix >= 2 && radix <= 36);
182
183    if (*string == '-') {
184	sign = -1;
185	string++;
186    } else if (*string == '+')
187	string++;
188    if (base == 0 && *string == '0') {
189	numberFound = true;
190	if (*(string+1) == 'x' || *(string+1) == 'X') {
191	    radix = 16;
192	    string += 2;
193	} else {
194	    radix = 8;
195	    string++;
196	}
197    }
198    do {
199	int digit = -1;
200	if (radix <= 10) {
201	    if (*string >= '0' && *string < '0' + radix)
202		digit = *string - '0';
203	} else {
204	    if (*string >= '0' && *string <= '9')
205		digit = *string - '0';
206	    else if (*string >= 'a' && *string < 'a' + radix - 10)
207		digit = *string - 'a' + 10;
208	    else if (*string >= 'A' && *string < 'A' + radix - 10)
209		digit = *string - 'A' + 10;
210	}
211	if (digit != -1) {
212	    numberFound = true;
213	    result = radix*result + digit;
214	    string++;
215	} else
216	    break;
217    } while (true);
218    *tail = numberFound ? string : start;
219    return sign * result;
220}
221
222/** \brief Locale-independent floating-point parser.
223 *
224 * Works similar to strtod. Leading space is NOT skipped. The input
225 * number may have an optional sign. '.' is interpreted as decimal
226 * point and may occur at most once. Optionally the number may end in
227 * [eE]<exponent>, where <exponent> is an integer as recognized by
228 * strToI. In that case the result is number * 10^exponent. After
229 * returning tail points to the first character that is not part of
230 * the floating point number. If no number was found then tail points
231 * to the start of the input string.
232 *
233 * Uses two passes for maximum accuracy. */
234static float strToF (const XML_Char *string, const XML_Char **tail) {
235    int nDigits = 0, pointPos, exponent;
236    float sign = 1.0f, result = 0.0f, scale;
237    const XML_Char *start = string, *numStart;
238
239    /* sign */
240    if (*string == '-') {
241	sign = -1.0f;
242	string++;
243    } else if (*string == '+')
244	string++;
245
246    /* first pass: determine position of decimal point, number of
247     * digits, exponent and the end of the number. */
248    numStart = string;
249    while (*string >= '0' && *string <= '9') {
250	string++;
251	nDigits++;
252    }
253    pointPos = nDigits;
254    if (*string == '.') {
255	string++;
256	while (*string >= '0' && *string <= '9') {
257	    string++;
258	    nDigits++;
259	}
260    }
261    if (nDigits == 0) {
262	/* no digits, no number */
263	*tail = start;
264	return 0.0f;
265    }
266    *tail = string;
267    if (*string == 'e' || *string == 'E') {
268	const XML_Char *expTail;
269	exponent = strToI (string+1, &expTail, 10);
270	if (expTail == string+1)
271	    exponent = 0;
272	else
273	    *tail = expTail;
274    } else
275	exponent = 0;
276    string = numStart;
277
278    /* scale of the first digit */
279    scale = sign * (float)pow (10.0, (double)(pointPos-1 + exponent));
280
281    /* second pass: parse digits */
282    do {
283	if (*string != '.') {
284	    assert (*string >= '0' && *string <= '9');
285	    result += scale * (float)(*string - '0');
286	    scale *= 0.1f;
287	    nDigits--;
288	}
289	string++;
290    } while (nDigits > 0);
291
292    return result;
293}
294
295/** \brief Parse a value of a given type. */
296static unsigned char parseValue (driOptionValue *v, driOptionType type,
297			     const XML_Char *string) {
298    const XML_Char *tail = NULL;
299  /* skip leading white-space */
300    string += strspn (string, " \f\n\r\t\v");
301    switch (type) {
302      case DRI_BOOL:
303	if (!strcmp (string, "false")) {
304	    v->_bool = false;
305	    tail = string + 5;
306	} else if (!strcmp (string, "true")) {
307	    v->_bool = true;
308	    tail = string + 4;
309	}
310	else
311	    return false;
312	break;
313      case DRI_ENUM: /* enum is just a special integer */
314      case DRI_INT:
315	v->_int = strToI (string, &tail, 0);
316	break;
317      case DRI_FLOAT:
318	v->_float = strToF (string, &tail);
319	break;
320      case DRI_STRING:
321	free (v->_string);
322	v->_string = strndup(string, STRING_CONF_MAXLEN);
323	return GL_TRUE;
324    }
325
326    if (tail == string)
327	return false; /* empty string (or containing only white-space) */
328  /* skip trailing white space */
329    if (*tail)
330	tail += strspn (tail, " \f\n\r\t\v");
331    if (*tail)
332	return false; /* something left over that is not part of value */
333
334    return true;
335}
336
337/** \brief Parse a list of ranges of type info->type. */
338static unsigned char parseRanges (driOptionInfo *info, const XML_Char *string) {
339    XML_Char *cp, *range;
340    uint32_t nRanges, i;
341    driOptionRange *ranges;
342
343    XSTRDUP (cp, string);
344  /* pass 1: determine the number of ranges (number of commas + 1) */
345    range = cp;
346    for (nRanges = 1; *range; ++range)
347	if (*range == ',')
348	    ++nRanges;
349
350    if ((ranges = malloc(nRanges*sizeof(driOptionRange))) == NULL) {
351	fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
352	abort();
353    }
354
355  /* pass 2: parse all ranges into preallocated array */
356    range = cp;
357    for (i = 0; i < nRanges; ++i) {
358	XML_Char *end, *sep;
359	assert (range);
360	end = strchr (range, ',');
361	if (end)
362	    *end = '\0';
363	sep = strchr (range, ':');
364	if (sep) { /* non-empty interval */
365	    *sep = '\0';
366	    if (!parseValue (&ranges[i].start, info->type, range) ||
367		!parseValue (&ranges[i].end, info->type, sep+1))
368	        break;
369	    if (info->type == DRI_INT &&
370		ranges[i].start._int > ranges[i].end._int)
371		break;
372	    if (info->type == DRI_FLOAT &&
373		ranges[i].start._float > ranges[i].end._float)
374		break;
375	} else { /* empty interval */
376	    if (!parseValue (&ranges[i].start, info->type, range))
377		break;
378	    ranges[i].end = ranges[i].start;
379	}
380	if (end)
381	    range = end+1;
382	else
383	    range = NULL;
384    }
385    free(cp);
386    if (i < nRanges) {
387	free(ranges);
388	return false;
389    } else
390	assert (range == NULL);
391
392    info->nRanges = nRanges;
393    info->ranges = ranges;
394    return true;
395}
396
397/** \brief Check if a value is in one of info->ranges. */
398static bool checkValue (const driOptionValue *v, const driOptionInfo *info) {
399    uint32_t i;
400    assert (info->type != DRI_BOOL); /* should be caught by the parser */
401    if (info->nRanges == 0)
402	return true;
403    switch (info->type) {
404      case DRI_ENUM: /* enum is just a special integer */
405      case DRI_INT:
406	for (i = 0; i < info->nRanges; ++i)
407	    if (v->_int >= info->ranges[i].start._int &&
408		v->_int <= info->ranges[i].end._int)
409		return true;
410	break;
411      case DRI_FLOAT:
412	for (i = 0; i < info->nRanges; ++i)
413	    if (v->_float >= info->ranges[i].start._float &&
414		v->_float <= info->ranges[i].end._float)
415		return true;
416	break;
417      case DRI_STRING:
418	break;
419      default:
420	assert (0); /* should never happen */
421    }
422    return false;
423}
424
425/**
426 * Print message to \c stderr if the \c LIBGL_DEBUG environment variable
427 * is set.
428 *
429 * Is called from the drivers.
430 *
431 * \param f \c printf like format string.
432 */
433static void
434__driUtilMessage(const char *f, ...)
435{
436    va_list args;
437    const char *libgl_debug;
438
439    libgl_debug=getenv("LIBGL_DEBUG");
440    if (libgl_debug && !strstr(libgl_debug, "quiet")) {
441        fprintf(stderr, "libGL: ");
442        va_start(args, f);
443        vfprintf(stderr, f, args);
444        va_end(args);
445        fprintf(stderr, "\n");
446    }
447}
448
449/** \brief Output a warning message. */
450#define XML_WARNING1(msg) do {\
451    __driUtilMessage ("Warning in %s line %d, column %d: "msg, data->name, \
452                      (int) XML_GetCurrentLineNumber(data->parser), \
453                      (int) XML_GetCurrentColumnNumber(data->parser)); \
454} while (0)
455#define XML_WARNING(msg,args...) do { \
456    __driUtilMessage ("Warning in %s line %d, column %d: "msg, data->name, \
457                      (int) XML_GetCurrentLineNumber(data->parser), \
458                      (int) XML_GetCurrentColumnNumber(data->parser), \
459                      args); \
460} while (0)
461/** \brief Output an error message. */
462#define XML_ERROR1(msg) do { \
463    __driUtilMessage ("Error in %s line %d, column %d: "msg, data->name, \
464                      (int) XML_GetCurrentLineNumber(data->parser), \
465                      (int) XML_GetCurrentColumnNumber(data->parser)); \
466} while (0)
467#define XML_ERROR(msg,args...) do { \
468    __driUtilMessage ("Error in %s line %d, column %d: "msg, data->name, \
469                      (int) XML_GetCurrentLineNumber(data->parser), \
470                      (int) XML_GetCurrentColumnNumber(data->parser), \
471                      args); \
472} while (0)
473/** \brief Output a fatal error message and abort. */
474#define XML_FATAL1(msg) do { \
475    fprintf (stderr, "Fatal error in %s line %d, column %d: "msg"\n", \
476             data->name, \
477             (int) XML_GetCurrentLineNumber(data->parser),	\
478             (int) XML_GetCurrentColumnNumber(data->parser)); \
479    abort();\
480} while (0)
481#define XML_FATAL(msg,args...) do { \
482    fprintf (stderr, "Fatal error in %s line %d, column %d: "msg"\n", \
483             data->name, \
484             (int) XML_GetCurrentLineNumber(data->parser),	\
485             (int) XML_GetCurrentColumnNumber(data->parser),		\
486             args); \
487    abort();\
488} while (0)
489
490/** \brief Parser context for __driConfigOptions. */
491struct OptInfoData {
492    const char *name;
493    XML_Parser parser;
494    driOptionCache *cache;
495    bool inDriInfo;
496    bool inSection;
497    bool inDesc;
498    bool inOption;
499    bool inEnum;
500    int curOption;
501};
502
503/** \brief Elements in __driConfigOptions. */
504enum OptInfoElem {
505    OI_DESCRIPTION = 0, OI_DRIINFO, OI_ENUM, OI_OPTION, OI_SECTION, OI_COUNT
506};
507static const XML_Char *OptInfoElems[] = {
508    "description", "driinfo", "enum", "option", "section"
509};
510
511/** \brief Parse attributes of an enum element.
512 *
513 * We're not actually interested in the data. Just make sure this is ok
514 * for external configuration tools.
515 */
516static void parseEnumAttr (struct OptInfoData *data, const XML_Char **attr) {
517    uint32_t i;
518    const XML_Char *value = NULL, *text = NULL;
519    driOptionValue v;
520    uint32_t opt = data->curOption;
521    for (i = 0; attr[i]; i += 2) {
522	if (!strcmp (attr[i], "value")) value = attr[i+1];
523	else if (!strcmp (attr[i], "text")) text = attr[i+1];
524	else XML_FATAL("illegal enum attribute: %s.", attr[i]);
525    }
526    if (!value) XML_FATAL1 ("value attribute missing in enum.");
527    if (!text) XML_FATAL1 ("text attribute missing in enum.");
528     if (!parseValue (&v, data->cache->info[opt].type, value))
529	XML_FATAL ("illegal enum value: %s.", value);
530    if (!checkValue (&v, &data->cache->info[opt]))
531	XML_FATAL ("enum value out of valid range: %s.", value);
532}
533
534/** \brief Parse attributes of a description element.
535 *
536 * We're not actually interested in the data. Just make sure this is ok
537 * for external configuration tools.
538 */
539static void parseDescAttr (struct OptInfoData *data, const XML_Char **attr) {
540    uint32_t i;
541    const XML_Char *lang = NULL, *text = NULL;
542    for (i = 0; attr[i]; i += 2) {
543	if (!strcmp (attr[i], "lang")) lang = attr[i+1];
544	else if (!strcmp (attr[i], "text")) text = attr[i+1];
545	else XML_FATAL("illegal description attribute: %s.", attr[i]);
546    }
547    if (!lang) XML_FATAL1 ("lang attribute missing in description.");
548    if (!text) XML_FATAL1 ("text attribute missing in description.");
549}
550
551/** \brief Parse attributes of an option element. */
552static void parseOptInfoAttr (struct OptInfoData *data, const XML_Char **attr) {
553    enum OptAttr {OA_DEFAULT = 0, OA_NAME, OA_TYPE, OA_VALID, OA_COUNT};
554    static const XML_Char *optAttr[] = {"default", "name", "type", "valid"};
555    const XML_Char *attrVal[OA_COUNT] = {NULL, NULL, NULL, NULL};
556    const char *defaultVal;
557    driOptionCache *cache = data->cache;
558    uint32_t opt, i;
559    for (i = 0; attr[i]; i += 2) {
560	uint32_t attrName = bsearchStr (attr[i], optAttr, OA_COUNT);
561	if (attrName >= OA_COUNT)
562	    XML_FATAL ("illegal option attribute: %s", attr[i]);
563	attrVal[attrName] = attr[i+1];
564    }
565    if (!attrVal[OA_NAME]) XML_FATAL1 ("name attribute missing in option.");
566    if (!attrVal[OA_TYPE]) XML_FATAL1 ("type attribute missing in option.");
567    if (!attrVal[OA_DEFAULT]) XML_FATAL1 ("default attribute missing in option.");
568
569    opt = findOption (cache, attrVal[OA_NAME]);
570    if (cache->info[opt].name)
571	XML_FATAL ("option %s redefined.", attrVal[OA_NAME]);
572    data->curOption = opt;
573
574    XSTRDUP (cache->info[opt].name, attrVal[OA_NAME]);
575
576    if (!strcmp (attrVal[OA_TYPE], "bool"))
577	cache->info[opt].type = DRI_BOOL;
578    else if (!strcmp (attrVal[OA_TYPE], "enum"))
579	cache->info[opt].type = DRI_ENUM;
580    else if (!strcmp (attrVal[OA_TYPE], "int"))
581	cache->info[opt].type = DRI_INT;
582    else if (!strcmp (attrVal[OA_TYPE], "float"))
583	cache->info[opt].type = DRI_FLOAT;
584    else if (!strcmp (attrVal[OA_TYPE], "string"))
585	cache->info[opt].type = DRI_STRING;
586    else
587	XML_FATAL ("illegal type in option: %s.", attrVal[OA_TYPE]);
588
589    defaultVal = getenv (cache->info[opt].name);
590    if (defaultVal != NULL) {
591      /* don't use XML_WARNING, we want the user to see this! */
592	fprintf (stderr,
593		 "ATTENTION: default value of option %s overridden by environment.\n",
594		 cache->info[opt].name);
595    } else
596	defaultVal = attrVal[OA_DEFAULT];
597    if (!parseValue (&cache->values[opt], cache->info[opt].type, defaultVal))
598	XML_FATAL ("illegal default value for %s: %s.", cache->info[opt].name, defaultVal);
599
600    if (attrVal[OA_VALID]) {
601	if (cache->info[opt].type == DRI_BOOL)
602	    XML_FATAL1 ("boolean option with valid attribute.");
603	if (!parseRanges (&cache->info[opt], attrVal[OA_VALID]))
604	    XML_FATAL ("illegal valid attribute: %s.", attrVal[OA_VALID]);
605	if (!checkValue (&cache->values[opt], &cache->info[opt]))
606	    XML_FATAL ("default value out of valid range '%s': %s.",
607		       attrVal[OA_VALID], defaultVal);
608    } else if (cache->info[opt].type == DRI_ENUM) {
609	XML_FATAL1 ("valid attribute missing in option (mandatory for enums).");
610    } else {
611	cache->info[opt].nRanges = 0;
612	cache->info[opt].ranges = NULL;
613    }
614}
615
616/** \brief Handler for start element events. */
617static void optInfoStartElem (void *userData, const XML_Char *name,
618			      const XML_Char **attr) {
619    struct OptInfoData *data = (struct OptInfoData *)userData;
620    enum OptInfoElem elem = bsearchStr (name, OptInfoElems, OI_COUNT);
621    switch (elem) {
622      case OI_DRIINFO:
623	if (data->inDriInfo)
624	    XML_FATAL1 ("nested <driinfo> elements.");
625	if (attr[0])
626	    XML_FATAL1 ("attributes specified on <driinfo> element.");
627	data->inDriInfo = true;
628	break;
629      case OI_SECTION:
630	if (!data->inDriInfo)
631	    XML_FATAL1 ("<section> must be inside <driinfo>.");
632	if (data->inSection)
633	    XML_FATAL1 ("nested <section> elements.");
634	if (attr[0])
635	    XML_FATAL1 ("attributes specified on <section> element.");
636	data->inSection = true;
637	break;
638      case OI_DESCRIPTION:
639	if (!data->inSection && !data->inOption)
640	    XML_FATAL1 ("<description> must be inside <description> or <option.");
641	if (data->inDesc)
642	    XML_FATAL1 ("nested <description> elements.");
643	data->inDesc = true;
644	parseDescAttr (data, attr);
645	break;
646      case OI_OPTION:
647	if (!data->inSection)
648	    XML_FATAL1 ("<option> must be inside <section>.");
649	if (data->inDesc)
650	    XML_FATAL1 ("<option> nested in <description> element.");
651	if (data->inOption)
652	    XML_FATAL1 ("nested <option> elements.");
653	data->inOption = true;
654	parseOptInfoAttr (data, attr);
655	break;
656      case OI_ENUM:
657	if (!(data->inOption && data->inDesc))
658	    XML_FATAL1 ("<enum> must be inside <option> and <description>.");
659	if (data->inEnum)
660	    XML_FATAL1 ("nested <enum> elements.");
661	data->inEnum = true;
662	parseEnumAttr (data, attr);
663	break;
664      default:
665	XML_FATAL ("unknown element: %s.", name);
666    }
667}
668
669/** \brief Handler for end element events. */
670static void optInfoEndElem (void *userData, const XML_Char *name) {
671    struct OptInfoData *data = (struct OptInfoData *)userData;
672    enum OptInfoElem elem = bsearchStr (name, OptInfoElems, OI_COUNT);
673    switch (elem) {
674      case OI_DRIINFO:
675	data->inDriInfo = false;
676	break;
677      case OI_SECTION:
678	data->inSection = false;
679	break;
680      case OI_DESCRIPTION:
681	data->inDesc = false;
682	break;
683      case OI_OPTION:
684	data->inOption = false;
685	break;
686      case OI_ENUM:
687	data->inEnum = false;
688	break;
689      default:
690	assert (0); /* should have been caught by StartElem */
691    }
692}
693
694void driParseOptionInfo (driOptionCache *info, const char *configOptions) {
695    XML_Parser p;
696    int status;
697    struct OptInfoData userData;
698    struct OptInfoData *data = &userData;
699
700    /* Make the hash table big enough to fit more than the maximum number of
701     * config options we've ever seen in a driver.
702     */
703    info->tableSize = 6;
704    info->info = calloc(1 << info->tableSize, sizeof (driOptionInfo));
705    info->values = calloc(1 << info->tableSize, sizeof (driOptionValue));
706    if (info->info == NULL || info->values == NULL) {
707	fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
708	abort();
709    }
710
711    p = XML_ParserCreate ("UTF-8"); /* always UTF-8 */
712    XML_SetElementHandler (p, optInfoStartElem, optInfoEndElem);
713    XML_SetUserData (p, data);
714
715    userData.name = "__driConfigOptions";
716    userData.parser = p;
717    userData.cache = info;
718    userData.inDriInfo = false;
719    userData.inSection = false;
720    userData.inDesc = false;
721    userData.inOption = false;
722    userData.inEnum = false;
723    userData.curOption = -1;
724
725    status = XML_Parse (p, configOptions, strlen (configOptions), 1);
726    if (!status)
727	XML_FATAL ("%s.", XML_ErrorString(XML_GetErrorCode(p)));
728
729    XML_ParserFree (p);
730}
731
732/** \brief Parser context for configuration files. */
733struct OptConfData {
734    const char *name;
735    XML_Parser parser;
736    driOptionCache *cache;
737    int screenNum;
738    const char *driverName, *execName;
739    uint32_t ignoringDevice;
740    uint32_t ignoringApp;
741    uint32_t inDriConf;
742    uint32_t inDevice;
743    uint32_t inApp;
744    uint32_t inOption;
745};
746
747/** \brief Elements in configuration files. */
748enum OptConfElem {
749    OC_APPLICATION = 0, OC_DEVICE, OC_DRICONF, OC_OPTION, OC_COUNT
750};
751static const XML_Char *OptConfElems[] = {
752    "application", "device", "driconf", "option"
753};
754
755/** \brief Parse attributes of a device element. */
756static void parseDeviceAttr (struct OptConfData *data, const XML_Char **attr) {
757    uint32_t i;
758    const XML_Char *driver = NULL, *screen = NULL;
759    for (i = 0; attr[i]; i += 2) {
760	if (!strcmp (attr[i], "driver")) driver = attr[i+1];
761	else if (!strcmp (attr[i], "screen")) screen = attr[i+1];
762	else XML_WARNING("unknown device attribute: %s.", attr[i]);
763    }
764    if (driver && strcmp (driver, data->driverName))
765	data->ignoringDevice = data->inDevice;
766    else if (screen) {
767	driOptionValue screenNum;
768	if (!parseValue (&screenNum, DRI_INT, screen))
769	    XML_WARNING("illegal screen number: %s.", screen);
770	else if (screenNum._int != data->screenNum)
771	    data->ignoringDevice = data->inDevice;
772    }
773}
774
775/** \brief Parse attributes of an application element. */
776static void parseAppAttr (struct OptConfData *data, const XML_Char **attr) {
777    uint32_t i;
778    const XML_Char *exec = NULL;
779    for (i = 0; attr[i]; i += 2) {
780	if (!strcmp (attr[i], "name")) /* not needed here */;
781	else if (!strcmp (attr[i], "executable")) exec = attr[i+1];
782	else XML_WARNING("unknown application attribute: %s.", attr[i]);
783    }
784    if (exec && strcmp (exec, data->execName))
785	data->ignoringApp = data->inApp;
786}
787
788/** \brief Parse attributes of an option element. */
789static void parseOptConfAttr (struct OptConfData *data, const XML_Char **attr) {
790    uint32_t i;
791    const XML_Char *name = NULL, *value = NULL;
792    for (i = 0; attr[i]; i += 2) {
793	if (!strcmp (attr[i], "name")) name = attr[i+1];
794	else if (!strcmp (attr[i], "value")) value = attr[i+1];
795	else XML_WARNING("unknown option attribute: %s.", attr[i]);
796    }
797    if (!name) XML_WARNING1 ("name attribute missing in option.");
798    if (!value) XML_WARNING1 ("value attribute missing in option.");
799    if (name && value) {
800	driOptionCache *cache = data->cache;
801	uint32_t opt = findOption (cache, name);
802	if (cache->info[opt].name == NULL)
803            /* don't use XML_WARNING, drirc defines options for all drivers,
804             * but not all drivers support them */
805            return;
806	else if (getenv (cache->info[opt].name))
807	  /* don't use XML_WARNING, we want the user to see this! */
808	    fprintf (stderr, "ATTENTION: option value of option %s ignored.\n",
809		     cache->info[opt].name);
810	else if (!parseValue (&cache->values[opt], cache->info[opt].type, value))
811	    XML_WARNING ("illegal option value: %s.", value);
812    }
813}
814
815/** \brief Handler for start element events. */
816static void optConfStartElem (void *userData, const XML_Char *name,
817			      const XML_Char **attr) {
818    struct OptConfData *data = (struct OptConfData *)userData;
819    enum OptConfElem elem = bsearchStr (name, OptConfElems, OC_COUNT);
820    switch (elem) {
821      case OC_DRICONF:
822	if (data->inDriConf)
823	    XML_WARNING1 ("nested <driconf> elements.");
824	if (attr[0])
825	    XML_WARNING1 ("attributes specified on <driconf> element.");
826	data->inDriConf++;
827	break;
828      case OC_DEVICE:
829	if (!data->inDriConf)
830	    XML_WARNING1 ("<device> should be inside <driconf>.");
831	if (data->inDevice)
832	    XML_WARNING1 ("nested <device> elements.");
833	data->inDevice++;
834	if (!data->ignoringDevice && !data->ignoringApp)
835	    parseDeviceAttr (data, attr);
836	break;
837      case OC_APPLICATION:
838	if (!data->inDevice)
839	    XML_WARNING1 ("<application> should be inside <device>.");
840	if (data->inApp)
841	    XML_WARNING1 ("nested <application> elements.");
842	data->inApp++;
843	if (!data->ignoringDevice && !data->ignoringApp)
844	    parseAppAttr (data, attr);
845	break;
846      case OC_OPTION:
847	if (!data->inApp)
848	    XML_WARNING1 ("<option> should be inside <application>.");
849	if (data->inOption)
850	    XML_WARNING1 ("nested <option> elements.");
851	data->inOption++;
852	if (!data->ignoringDevice && !data->ignoringApp)
853	    parseOptConfAttr (data, attr);
854	break;
855      default:
856	XML_WARNING ("unknown element: %s.", name);
857    }
858}
859
860/** \brief Handler for end element events. */
861static void optConfEndElem (void *userData, const XML_Char *name) {
862    struct OptConfData *data = (struct OptConfData *)userData;
863    enum OptConfElem elem = bsearchStr (name, OptConfElems, OC_COUNT);
864    switch (elem) {
865      case OC_DRICONF:
866	data->inDriConf--;
867	break;
868      case OC_DEVICE:
869	if (data->inDevice-- == data->ignoringDevice)
870	    data->ignoringDevice = 0;
871	break;
872      case OC_APPLICATION:
873	if (data->inApp-- == data->ignoringApp)
874	    data->ignoringApp = 0;
875	break;
876      case OC_OPTION:
877	data->inOption--;
878	break;
879      default:
880	/* unknown element, warning was produced on start tag */;
881    }
882}
883
884/** \brief Initialize an option cache based on info */
885static void initOptionCache (driOptionCache *cache, const driOptionCache *info) {
886    GLuint i, size = 1 << info->tableSize;
887    cache->info = info->info;
888    cache->tableSize = info->tableSize;
889    cache->values = malloc((1<<info->tableSize) * sizeof (driOptionValue));
890    if (cache->values == NULL) {
891	fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
892	abort();
893    }
894    memcpy (cache->values, info->values,
895	    (1<<info->tableSize) * sizeof (driOptionValue));
896    for (i = 0; i < size; ++i) {
897	if (cache->info[i].type == DRI_STRING)
898	    XSTRDUP(cache->values[i]._string, info->values[i]._string);
899    }
900}
901
902/** \brief Parse the named configuration file */
903static void parseOneConfigFile (XML_Parser p) {
904#define BUF_SIZE 0x1000
905    struct OptConfData *data = (struct OptConfData *)XML_GetUserData (p);
906    int status;
907    int fd;
908
909    if ((fd = open (data->name, O_RDONLY)) == -1) {
910	__driUtilMessage ("Can't open configuration file %s: %s.",
911			  data->name, strerror (errno));
912	return;
913    }
914
915    while (1) {
916	int bytesRead;
917	void *buffer = XML_GetBuffer (p, BUF_SIZE);
918	if (!buffer) {
919	    __driUtilMessage ("Can't allocate parser buffer.");
920	    break;
921	}
922	bytesRead = read (fd, buffer, BUF_SIZE);
923	if (bytesRead == -1) {
924	    __driUtilMessage ("Error reading from configuration file %s: %s.",
925			      data->name, strerror (errno));
926	    break;
927	}
928	status = XML_ParseBuffer (p, bytesRead, bytesRead == 0);
929	if (!status) {
930	    XML_ERROR ("%s.", XML_ErrorString(XML_GetErrorCode(p)));
931	    break;
932	}
933	if (bytesRead == 0)
934	    break;
935    }
936
937    close (fd);
938#undef BUF_SIZE
939}
940
941#ifndef SYSCONFDIR
942#define SYSCONFDIR "/etc"
943#endif
944
945void driParseConfigFiles (driOptionCache *cache, const driOptionCache *info,
946			  int screenNum, const char *driverName) {
947    char *filenames[2] = { SYSCONFDIR "/drirc", NULL};
948    char *home;
949    uint32_t i;
950    struct OptConfData userData;
951
952    initOptionCache (cache, info);
953
954    userData.cache = cache;
955    userData.screenNum = screenNum;
956    userData.driverName = driverName;
957    userData.execName = GET_PROGRAM_NAME();
958
959    if ((home = getenv ("HOME"))) {
960	uint32_t len = strlen (home);
961	filenames[1] = malloc(len + 7+1);
962	if (filenames[1] == NULL)
963	    __driUtilMessage ("Can't allocate memory for %s/.drirc.", home);
964	else {
965	    memcpy (filenames[1], home, len);
966	    memcpy (filenames[1] + len, "/.drirc", 7+1);
967	}
968    }
969
970    for (i = 0; i < 2; ++i) {
971	XML_Parser p;
972	if (filenames[i] == NULL)
973	    continue;
974
975	p = XML_ParserCreate (NULL); /* use encoding specified by file */
976	XML_SetElementHandler (p, optConfStartElem, optConfEndElem);
977	XML_SetUserData (p, &userData);
978	userData.parser = p;
979	userData.name = filenames[i];
980	userData.ignoringDevice = 0;
981	userData.ignoringApp = 0;
982	userData.inDriConf = 0;
983	userData.inDevice = 0;
984	userData.inApp = 0;
985	userData.inOption = 0;
986
987	parseOneConfigFile (p);
988	XML_ParserFree (p);
989    }
990
991    free(filenames[1]);
992}
993
994void driDestroyOptionInfo (driOptionCache *info) {
995    driDestroyOptionCache (info);
996    if (info->info) {
997	uint32_t i, size = 1 << info->tableSize;
998	for (i = 0; i < size; ++i) {
999	    if (info->info[i].name) {
1000		free(info->info[i].name);
1001		free(info->info[i].ranges);
1002	    }
1003	}
1004	free(info->info);
1005    }
1006}
1007
1008void driDestroyOptionCache (driOptionCache *cache) {
1009    if (cache->info) {
1010	GLuint i, size = 1 << cache->tableSize;
1011	for (i = 0; i < size; ++i) {
1012	    if (cache->info[i].type == DRI_STRING)
1013		free(cache->values[i]._string);
1014	}
1015    }
1016    free(cache->values);
1017}
1018
1019unsigned char driCheckOption (const driOptionCache *cache, const char *name,
1020			  driOptionType type) {
1021    uint32_t i = findOption (cache, name);
1022    return cache->info[i].name != NULL && cache->info[i].type == type;
1023}
1024
1025unsigned char driQueryOptionb (const driOptionCache *cache, const char *name) {
1026    uint32_t i = findOption (cache, name);
1027  /* make sure the option is defined and has the correct type */
1028    assert (cache->info[i].name != NULL);
1029    assert (cache->info[i].type == DRI_BOOL);
1030    return cache->values[i]._bool;
1031}
1032
1033int driQueryOptioni (const driOptionCache *cache, const char *name) {
1034    uint32_t i = findOption (cache, name);
1035  /* make sure the option is defined and has the correct type */
1036    assert (cache->info[i].name != NULL);
1037    assert (cache->info[i].type == DRI_INT || cache->info[i].type == DRI_ENUM);
1038    return cache->values[i]._int;
1039}
1040
1041float driQueryOptionf (const driOptionCache *cache, const char *name) {
1042    uint32_t i = findOption (cache, name);
1043  /* make sure the option is defined and has the correct type */
1044    assert (cache->info[i].name != NULL);
1045    assert (cache->info[i].type == DRI_FLOAT);
1046    return cache->values[i]._float;
1047}
1048
1049char *driQueryOptionstr (const driOptionCache *cache, const char *name) {
1050    GLuint i = findOption (cache, name);
1051  /* make sure the option is defined and has the correct type */
1052    assert (cache->info[i].name != NULL);
1053    assert (cache->info[i].type == DRI_STRING);
1054    return cache->values[i]._string;
1055}
1056