xmlconfig: move into src/util

v2: attempt to fix Android build (Emil)

v3: add missing include path

Reviewed-by: Marek Olšák <[email protected]> (v1)

1 files changed, 1113 insertions, 0 deletions

diff --git a/src/util/xmlconfig.c b/src/util/xmlconfig.c
new file mode 100644
index 00000000000..d3f47ecda0c
--- /dev/null
+++ b/src/util/xmlconfig.c
@@ -0,0 +1,1113 @@
+/*
+ * XML DRI client-side driver configuration
+ * Copyright (C) 2003 Felix Kuehling
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * FELIX KUEHLING, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM, 
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE 
+ * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ * 
+ */
+/**
+ * \file xmlconfig.c
+ * \brief Driver-independent client-side part of the XML configuration
+ * \author Felix Kuehling
+ */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <expat.h>
+#include <fcntl.h>
+#include <math.h>
+#include <unistd.h>
+#include <errno.h>
+#include "xmlconfig.h"
+
+#undef GET_PROGRAM_NAME
+
+#if (defined(__GNU_LIBRARY__) || defined(__GLIBC__)) && !defined(__UCLIBC__)
+#    if !defined(__GLIBC__) || (__GLIBC__ < 2)
+/* These aren't declared in any libc5 header */
+extern char *program_invocation_name, *program_invocation_short_name;
+#    endif
+#    define GET_PROGRAM_NAME() program_invocation_short_name
+#elif defined(__CYGWIN__)
+#    define GET_PROGRAM_NAME() program_invocation_short_name
+#elif defined(__FreeBSD__) && (__FreeBSD__ >= 2)
+#    include <osreldate.h>
+#    if (__FreeBSD_version >= 440000)
+#        include <stdlib.h>
+#        define GET_PROGRAM_NAME() getprogname()
+#    endif
+#elif defined(__NetBSD__) && defined(__NetBSD_Version__) && (__NetBSD_Version__ >= 106000100)
+#    include <stdlib.h>
+#    define GET_PROGRAM_NAME() getprogname()
+#elif defined(__DragonFly__)
+#    include <stdlib.h>
+#    define GET_PROGRAM_NAME() getprogname()
+#elif defined(__APPLE__)
+#    include <stdlib.h>
+#    define GET_PROGRAM_NAME() getprogname()
+#elif defined(__sun)
+/* Solaris has getexecname() which returns the full path - return just
+   the basename to match BSD getprogname() */
+#    include <stdlib.h>
+#    include <libgen.h>
+
+static const char *
+__getProgramName()
+{
+    static const char *progname;
+
+    if (progname == NULL) {
+        const char *e = getexecname();
+        if (e != NULL) {
+            /* Have to make a copy since getexecname can return a readonly
+               string, but basename expects to be able to modify its arg. */
+            char *n = strdup(e);
+            if (n != NULL) {
+                progname = basename(n);
+            }
+        }
+    }
+    return progname;
+}
+
+#    define GET_PROGRAM_NAME() __getProgramName()
+#endif
+
+#if !defined(GET_PROGRAM_NAME)
+#    if defined(__OpenBSD__) || defined(NetBSD) || defined(__UCLIBC__) || defined(ANDROID)
+/* This is a hack. It's said to work on OpenBSD, NetBSD and GNU.
+ * Rogelio M.Serrano Jr. reported it's also working with UCLIBC. It's
+ * used as a last resort, if there is no documented facility available. */
+static const char *
+__getProgramName()
+{
+    extern const char *__progname;
+    char * arg = strrchr(__progname, '/');
+    if (arg)
+        return arg+1;
+    else
+        return __progname;
+}
+#        define GET_PROGRAM_NAME() __getProgramName()
+#    else
+#        define GET_PROGRAM_NAME() ""
+#        warning "Per application configuration won't work with your OS version."
+#    endif
+#endif
+
+/** \brief Find an option in an option cache with the name as key */
+static uint32_t
+findOption(const driOptionCache *cache, const char *name)
+{
+    uint32_t len = strlen (name);
+    uint32_t size = 1 << cache->tableSize, mask = size - 1;
+    uint32_t hash = 0;
+    uint32_t i, shift;
+
+  /* compute a hash from the variable length name */
+    for (i = 0, shift = 0; i < len; ++i, shift = (shift+8) & 31)
+        hash += (uint32_t)name[i] << shift;
+    hash *= hash;
+    hash = (hash >> (16-cache->tableSize/2)) & mask;
+
+  /* this is just the starting point of the linear search for the option */
+    for (i = 0; i < size; ++i, hash = (hash+1) & mask) {
+      /* if we hit an empty entry then the option is not defined (yet) */
+        if (cache->info[hash].name == 0)
+            break;
+        else if (!strcmp (name, cache->info[hash].name))
+            break;
+    }
+  /* this assertion fails if the hash table is full */
+    assert (i < size);
+
+    return hash;
+}
+
+/** \brief Like strdup but using malloc and with error checking. */
+#define XSTRDUP(dest,source) do { \
+    uint32_t len = strlen (source); \
+    if (!(dest = malloc(len+1))) { \
+        fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__); \
+        abort(); \
+    } \
+    memcpy (dest, source, len+1); \
+} while (0)
+
+static int compare (const void *a, const void *b) {
+    return strcmp (*(char *const*)a, *(char *const*)b);
+}
+/** \brief Binary search in a string array. */
+static uint32_t
+bsearchStr (const XML_Char *name, const XML_Char *elems[], uint32_t count)
+{
+    const XML_Char **found;
+    found = bsearch (&name, elems, count, sizeof (XML_Char *), compare);
+    if (found)
+        return found - elems;
+    else
+        return count;
+}
+
+/** \brief Locale-independent integer parser.
+ *
+ * Works similar to strtol. Leading space is NOT skipped. The input
+ * number may have an optional sign. Radix is specified by base. If
+ * base is 0 then decimal is assumed unless the input number is
+ * prefixed by 0x or 0X for hexadecimal or 0 for octal. After
+ * returning tail points to the first character that is not part of
+ * the integer number. If no number was found then tail points to the
+ * start of the input string. */
+static int
+strToI(const XML_Char *string, const XML_Char **tail, int base)
+{
+    int radix = base == 0 ? 10 : base;
+    int result = 0;
+    int sign = 1;
+    bool numberFound = false;
+    const XML_Char *start = string;
+
+    assert (radix >= 2 && radix <= 36);
+
+    if (*string == '-') {
+        sign = -1;
+        string++;
+    } else if (*string == '+')
+        string++;
+    if (base == 0 && *string == '0') {
+        numberFound = true;
+        if (*(string+1) == 'x' || *(string+1) == 'X') {
+            radix = 16;
+            string += 2;
+        } else {
+            radix = 8;
+            string++;
+        }
+    }
+    do {
+        int digit = -1;
+        if (radix <= 10) {
+            if (*string >= '0' && *string < '0' + radix)
+                digit = *string - '0';
+        } else {
+            if (*string >= '0' && *string <= '9')
+                digit = *string - '0';
+            else if (*string >= 'a' && *string < 'a' + radix - 10)
+                digit = *string - 'a' + 10;
+            else if (*string >= 'A' && *string < 'A' + radix - 10)
+                digit = *string - 'A' + 10;
+        }
+        if (digit != -1) {
+            numberFound = true;
+            result = radix*result + digit;
+            string++;
+        } else
+            break;
+    } while (true);
+    *tail = numberFound ? string : start;
+    return sign * result;
+}
+
+/** \brief Locale-independent floating-point parser.
+ *
+ * Works similar to strtod. Leading space is NOT skipped. The input
+ * number may have an optional sign. '.' is interpreted as decimal
+ * point and may occur at most once. Optionally the number may end in
+ * [eE]<exponent>, where <exponent> is an integer as recognized by
+ * strToI. In that case the result is number * 10^exponent. After
+ * returning tail points to the first character that is not part of
+ * the floating point number. If no number was found then tail points
+ * to the start of the input string.
+ *
+ * Uses two passes for maximum accuracy. */
+static float
+strToF(const XML_Char *string, const XML_Char **tail)
+{
+    int nDigits = 0, pointPos, exponent;
+    float sign = 1.0f, result = 0.0f, scale;
+    const XML_Char *start = string, *numStart;
+
+    /* sign */
+    if (*string == '-') {
+        sign = -1.0f;
+        string++;
+    } else if (*string == '+')
+        string++;
+
+    /* first pass: determine position of decimal point, number of
+     * digits, exponent and the end of the number. */
+    numStart = string;
+    while (*string >= '0' && *string <= '9') {
+        string++;
+        nDigits++;
+    }
+    pointPos = nDigits;
+    if (*string == '.') {
+        string++;
+        while (*string >= '0' && *string <= '9') {
+            string++;
+            nDigits++;
+        }
+    }
+    if (nDigits == 0) {
+        /* no digits, no number */
+        *tail = start;
+        return 0.0f;
+    }
+    *tail = string;
+    if (*string == 'e' || *string == 'E') {
+        const XML_Char *expTail;
+        exponent = strToI (string+1, &expTail, 10);
+        if (expTail == string+1)
+            exponent = 0;
+        else
+            *tail = expTail;
+    } else
+        exponent = 0;
+    string = numStart;
+
+    /* scale of the first digit */
+    scale = sign * (float)pow (10.0, (double)(pointPos-1 + exponent));
+
+    /* second pass: parse digits */
+    do {
+        if (*string != '.') {
+            assert (*string >= '0' && *string <= '9');
+            result += scale * (float)(*string - '0');
+            scale *= 0.1f;
+            nDigits--;
+        }
+        string++;
+    } while (nDigits > 0);
+
+    return result;
+}
+
+/** \brief Parse a value of a given type. */
+static unsigned char
+parseValue(driOptionValue *v, driOptionType type, const XML_Char *string)
+{
+    const XML_Char *tail = NULL;
+  /* skip leading white-space */
+    string += strspn (string, " \f\n\r\t\v");
+    switch (type) {
+      case DRI_BOOL:
+        if (!strcmp (string, "false")) {
+            v->_bool = false;
+            tail = string + 5;
+        } else if (!strcmp (string, "true")) {
+            v->_bool = true;
+            tail = string + 4;
+        }
+        else
+            return false;
+        break;
+      case DRI_ENUM: /* enum is just a special integer */
+      case DRI_INT:
+        v->_int = strToI (string, &tail, 0);
+        break;
+      case DRI_FLOAT:
+        v->_float = strToF (string, &tail);
+        break;
+      case DRI_STRING:
+        free (v->_string);
+        v->_string = strndup(string, STRING_CONF_MAXLEN);
+        return true;
+    }
+
+    if (tail == string)
+        return false; /* empty string (or containing only white-space) */
+  /* skip trailing white space */
+    if (*tail)
+        tail += strspn (tail, " \f\n\r\t\v");
+    if (*tail)
+        return false; /* something left over that is not part of value */
+
+    return true;
+}
+
+/** \brief Parse a list of ranges of type info->type. */
+static unsigned char
+parseRanges(driOptionInfo *info, const XML_Char *string)
+{
+    XML_Char *cp, *range;
+    uint32_t nRanges, i;
+    driOptionRange *ranges;
+
+    XSTRDUP (cp, string);
+  /* pass 1: determine the number of ranges (number of commas + 1) */
+    range = cp;
+    for (nRanges = 1; *range; ++range)
+        if (*range == ',')
+            ++nRanges;
+
+    if ((ranges = malloc(nRanges*sizeof(driOptionRange))) == NULL) {
+        fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
+        abort();
+    }
+
+  /* pass 2: parse all ranges into preallocated array */
+    range = cp;
+    for (i = 0; i < nRanges; ++i) {
+        XML_Char *end, *sep;
+        assert (range);
+        end = strchr (range, ',');
+        if (end)
+            *end = '\0';
+        sep = strchr (range, ':');
+        if (sep) { /* non-empty interval */
+            *sep = '\0';
+            if (!parseValue (&ranges[i].start, info->type, range) ||
+                !parseValue (&ranges[i].end, info->type, sep+1))
+                break;
+            if (info->type == DRI_INT &&
+                ranges[i].start._int > ranges[i].end._int)
+                break;
+            if (info->type == DRI_FLOAT &&
+                ranges[i].start._float > ranges[i].end._float)
+                break;
+        } else { /* empty interval */
+            if (!parseValue (&ranges[i].start, info->type, range))
+                break;
+            ranges[i].end = ranges[i].start;
+        }
+        if (end)
+            range = end+1;
+        else
+            range = NULL;
+    }
+    free(cp);
+    if (i < nRanges) {
+        free(ranges);
+        return false;
+    } else
+        assert (range == NULL);
+
+    info->nRanges = nRanges;
+    info->ranges = ranges;
+    return true;
+}
+
+/** \brief Check if a value is in one of info->ranges. */
+static bool
+checkValue(const driOptionValue *v, const driOptionInfo *info)
+{
+    uint32_t i;
+    assert (info->type != DRI_BOOL); /* should be caught by the parser */
+    if (info->nRanges == 0)
+        return true;
+    switch (info->type) {
+      case DRI_ENUM: /* enum is just a special integer */
+      case DRI_INT:
+        for (i = 0; i < info->nRanges; ++i)
+            if (v->_int >= info->ranges[i].start._int &&
+                v->_int <= info->ranges[i].end._int)
+                return true;
+        break;
+      case DRI_FLOAT:
+        for (i = 0; i < info->nRanges; ++i)
+            if (v->_float >= info->ranges[i].start._float &&
+                v->_float <= info->ranges[i].end._float)
+                return true;
+        break;
+      case DRI_STRING:
+        break;
+      default:
+        assert (0); /* should never happen */
+    }
+    return false;
+}
+
+/**
+ * Print message to \c stderr if the \c LIBGL_DEBUG environment variable
+ * is set. 
+ * 
+ * Is called from the drivers.
+ * 
+ * \param f \c printf like format string.
+ */
+static void
+__driUtilMessage(const char *f, ...)
+{
+    va_list args;
+    const char *libgl_debug;
+
+    libgl_debug=getenv("LIBGL_DEBUG");
+    if (libgl_debug && !strstr(libgl_debug, "quiet")) {
+        fprintf(stderr, "libGL: ");
+        va_start(args, f);
+        vfprintf(stderr, f, args);
+        va_end(args);
+        fprintf(stderr, "\n");
+    }
+}
+
+/** \brief Output a warning message. */
+#define XML_WARNING1(msg) do {\
+    __driUtilMessage ("Warning in %s line %d, column %d: "msg, data->name, \
+                      (int) XML_GetCurrentLineNumber(data->parser), \
+                      (int) XML_GetCurrentColumnNumber(data->parser)); \
+} while (0)
+#define XML_WARNING(msg,args...) do { \
+    __driUtilMessage ("Warning in %s line %d, column %d: "msg, data->name, \
+                      (int) XML_GetCurrentLineNumber(data->parser), \
+                      (int) XML_GetCurrentColumnNumber(data->parser), \
+                      args); \
+} while (0)
+/** \brief Output an error message. */
+#define XML_ERROR1(msg) do { \
+    __driUtilMessage ("Error in %s line %d, column %d: "msg, data->name, \
+                      (int) XML_GetCurrentLineNumber(data->parser), \
+                      (int) XML_GetCurrentColumnNumber(data->parser)); \
+} while (0)
+#define XML_ERROR(msg,args...) do { \
+    __driUtilMessage ("Error in %s line %d, column %d: "msg, data->name, \
+                      (int) XML_GetCurrentLineNumber(data->parser), \
+                      (int) XML_GetCurrentColumnNumber(data->parser), \
+                      args); \
+} while (0)
+/** \brief Output a fatal error message and abort. */
+#define XML_FATAL1(msg) do { \
+    fprintf (stderr, "Fatal error in %s line %d, column %d: "msg"\n", \
+             data->name, \
+             (int) XML_GetCurrentLineNumber(data->parser),        \
+             (int) XML_GetCurrentColumnNumber(data->parser)); \
+    abort();\
+} while (0)
+#define XML_FATAL(msg,args...) do { \
+    fprintf (stderr, "Fatal error in %s line %d, column %d: "msg"\n", \
+             data->name, \
+             (int) XML_GetCurrentLineNumber(data->parser), \
+             (int) XML_GetCurrentColumnNumber(data->parser), \
+             args); \
+    abort();\
+} while (0)
+
+/** \brief Parser context for __driConfigOptions. */
+struct OptInfoData {
+    const char *name;
+    XML_Parser parser;
+    driOptionCache *cache;
+    bool inDriInfo;
+    bool inSection;
+    bool inDesc;
+    bool inOption;
+    bool inEnum;
+    int curOption;
+};
+
+/** \brief Elements in __driConfigOptions. */
+enum OptInfoElem {
+    OI_DESCRIPTION = 0, OI_DRIINFO, OI_ENUM, OI_OPTION, OI_SECTION, OI_COUNT
+};
+static const XML_Char *OptInfoElems[] = {
+    "description", "driinfo", "enum", "option", "section"
+};
+
+/** \brief Parse attributes of an enum element.
+ *
+ * We're not actually interested in the data. Just make sure this is ok
+ * for external configuration tools.
+ */
+static void
+parseEnumAttr(struct OptInfoData *data, const XML_Char **attr)
+{
+    uint32_t i;
+    const XML_Char *value = NULL, *text = NULL;
+    driOptionValue v;
+    uint32_t opt = data->curOption;
+    for (i = 0; attr[i]; i += 2) {
+        if (!strcmp (attr[i], "value")) value = attr[i+1];
+        else if (!strcmp (attr[i], "text")) text = attr[i+1];
+        else XML_FATAL("illegal enum attribute: %s.", attr[i]);
+    }
+    if (!value) XML_FATAL1 ("value attribute missing in enum.");
+    if (!text) XML_FATAL1 ("text attribute missing in enum.");
+     if (!parseValue (&v, data->cache->info[opt].type, value))
+        XML_FATAL ("illegal enum value: %s.", value);
+    if (!checkValue (&v, &data->cache->info[opt]))
+        XML_FATAL ("enum value out of valid range: %s.", value);
+}
+
+/** \brief Parse attributes of a description element.
+ *
+ * We're not actually interested in the data. Just make sure this is ok
+ * for external configuration tools.
+ */
+static void
+parseDescAttr(struct OptInfoData *data, const XML_Char **attr)
+{
+    uint32_t i;
+    const XML_Char *lang = NULL, *text = NULL;
+    for (i = 0; attr[i]; i += 2) {
+        if (!strcmp (attr[i], "lang")) lang = attr[i+1];
+        else if (!strcmp (attr[i], "text")) text = attr[i+1];
+        else XML_FATAL("illegal description attribute: %s.", attr[i]);
+    }
+    if (!lang) XML_FATAL1 ("lang attribute missing in description.");
+    if (!text) XML_FATAL1 ("text attribute missing in description.");
+}
+
+/** \brief Parse attributes of an option element. */
+static void
+parseOptInfoAttr(struct OptInfoData *data, const XML_Char **attr)
+{
+    enum OptAttr {OA_DEFAULT = 0, OA_NAME, OA_TYPE, OA_VALID, OA_COUNT};
+    static const XML_Char *optAttr[] = {"default", "name", "type", "valid"};
+    const XML_Char *attrVal[OA_COUNT] = {NULL, NULL, NULL, NULL};
+    const char *defaultVal;
+    driOptionCache *cache = data->cache;
+    uint32_t opt, i;
+    for (i = 0; attr[i]; i += 2) {
+        uint32_t attrName = bsearchStr (attr[i], optAttr, OA_COUNT);
+        if (attrName >= OA_COUNT)
+            XML_FATAL ("illegal option attribute: %s", attr[i]);
+        attrVal[attrName] = attr[i+1];
+    }
+    if (!attrVal[OA_NAME]) XML_FATAL1 ("name attribute missing in option.");
+    if (!attrVal[OA_TYPE]) XML_FATAL1 ("type attribute missing in option.");
+    if (!attrVal[OA_DEFAULT]) XML_FATAL1 ("default attribute missing in option.");
+
+    opt = findOption (cache, attrVal[OA_NAME]);
+    if (cache->info[opt].name)
+        XML_FATAL ("option %s redefined.", attrVal[OA_NAME]);
+    data->curOption = opt;
+
+    XSTRDUP (cache->info[opt].name, attrVal[OA_NAME]);
+
+    if (!strcmp (attrVal[OA_TYPE], "bool"))
+        cache->info[opt].type = DRI_BOOL;
+    else if (!strcmp (attrVal[OA_TYPE], "enum"))
+        cache->info[opt].type = DRI_ENUM;
+    else if (!strcmp (attrVal[OA_TYPE], "int"))
+        cache->info[opt].type = DRI_INT;
+    else if (!strcmp (attrVal[OA_TYPE], "float"))
+        cache->info[opt].type = DRI_FLOAT;
+    else if (!strcmp (attrVal[OA_TYPE], "string"))
+        cache->info[opt].type = DRI_STRING;
+    else
+        XML_FATAL ("illegal type in option: %s.", attrVal[OA_TYPE]);
+
+    defaultVal = getenv (cache->info[opt].name);
+    if (defaultVal != NULL) {
+      /* don't use XML_WARNING, we want the user to see this! */
+        fprintf (stderr,
+                 "ATTENTION: default value of option %s overridden by environment.\n",
+                 cache->info[opt].name);
+    } else
+        defaultVal = attrVal[OA_DEFAULT];
+    if (!parseValue (&cache->values[opt], cache->info[opt].type, defaultVal))
+        XML_FATAL ("illegal default value for %s: %s.", cache->info[opt].name, defaultVal);
+
+    if (attrVal[OA_VALID]) {
+        if (cache->info[opt].type == DRI_BOOL)
+            XML_FATAL1 ("boolean option with valid attribute.");
+        if (!parseRanges (&cache->info[opt], attrVal[OA_VALID]))
+            XML_FATAL ("illegal valid attribute: %s.", attrVal[OA_VALID]);
+        if (!checkValue (&cache->values[opt], &cache->info[opt]))
+            XML_FATAL ("default value out of valid range '%s': %s.",
+                       attrVal[OA_VALID], defaultVal);
+    } else if (cache->info[opt].type == DRI_ENUM) {
+        XML_FATAL1 ("valid attribute missing in option (mandatory for enums).");
+    } else {
+        cache->info[opt].nRanges = 0;
+        cache->info[opt].ranges = NULL;
+    }
+}
+
+/** \brief Handler for start element events. */
+static void
+optInfoStartElem(void *userData, const XML_Char *name, const XML_Char **attr)
+{
+    struct OptInfoData *data = (struct OptInfoData *)userData;
+    enum OptInfoElem elem = bsearchStr (name, OptInfoElems, OI_COUNT);
+    switch (elem) {
+      case OI_DRIINFO:
+        if (data->inDriInfo)
+            XML_FATAL1 ("nested <driinfo> elements.");
+        if (attr[0])
+            XML_FATAL1 ("attributes specified on <driinfo> element.");
+        data->inDriInfo = true;
+        break;
+      case OI_SECTION:
+        if (!data->inDriInfo)
+            XML_FATAL1 ("<section> must be inside <driinfo>.");
+        if (data->inSection)
+            XML_FATAL1 ("nested <section> elements.");
+        if (attr[0])
+            XML_FATAL1 ("attributes specified on <section> element.");
+        data->inSection = true;
+        break;
+      case OI_DESCRIPTION:
+        if (!data->inSection && !data->inOption)
+            XML_FATAL1 ("<description> must be inside <description> or <option.");
+        if (data->inDesc)
+            XML_FATAL1 ("nested <description> elements.");
+        data->inDesc = true;
+        parseDescAttr (data, attr);
+        break;
+      case OI_OPTION:
+        if (!data->inSection)
+            XML_FATAL1 ("<option> must be inside <section>.");
+        if (data->inDesc)
+            XML_FATAL1 ("<option> nested in <description> element.");
+        if (data->inOption)
+            XML_FATAL1 ("nested <option> elements.");
+        data->inOption = true;
+        parseOptInfoAttr (data, attr);
+        break;
+      case OI_ENUM:
+        if (!(data->inOption && data->inDesc))
+            XML_FATAL1 ("<enum> must be inside <option> and <description>.");
+        if (data->inEnum)
+            XML_FATAL1 ("nested <enum> elements.");
+        data->inEnum = true;
+        parseEnumAttr (data, attr);
+        break;
+      default:
+        XML_FATAL ("unknown element: %s.", name);
+    }
+}
+
+/** \brief Handler for end element events. */
+static void
+optInfoEndElem(void *userData, const XML_Char *name)
+{
+    struct OptInfoData *data = (struct OptInfoData *)userData;
+    enum OptInfoElem elem = bsearchStr (name, OptInfoElems, OI_COUNT);
+    switch (elem) {
+      case OI_DRIINFO:
+        data->inDriInfo = false;
+        break;
+      case OI_SECTION:
+        data->inSection = false;
+        break;
+      case OI_DESCRIPTION:
+        data->inDesc = false;
+        break;
+      case OI_OPTION:
+        data->inOption = false;
+        break;
+      case OI_ENUM:
+        data->inEnum = false;
+        break;
+      default:
+        assert (0); /* should have been caught by StartElem */
+    }
+}
+
+void
+driParseOptionInfo(driOptionCache *info, const char *configOptions)
+{
+    XML_Parser p;
+    int status;
+    struct OptInfoData userData;
+    struct OptInfoData *data = &userData;
+
+    /* Make the hash table big enough to fit more than the maximum number of
+     * config options we've ever seen in a driver.
+     */
+    info->tableSize = 6;
+    info->info = calloc(1 << info->tableSize, sizeof (driOptionInfo));
+    info->values = calloc(1 << info->tableSize, sizeof (driOptionValue));
+    if (info->info == NULL || info->values == NULL) {
+        fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
+        abort();
+    }
+
+    p = XML_ParserCreate ("UTF-8"); /* always UTF-8 */
+    XML_SetElementHandler (p, optInfoStartElem, optInfoEndElem);
+    XML_SetUserData (p, data);
+
+    userData.name = "__driConfigOptions";
+    userData.parser = p;
+    userData.cache = info;
+    userData.inDriInfo = false;
+    userData.inSection = false;
+    userData.inDesc = false;
+    userData.inOption = false;
+    userData.inEnum = false;
+    userData.curOption = -1;
+
+    status = XML_Parse (p, configOptions, strlen (configOptions), 1);
+    if (!status)
+        XML_FATAL ("%s.", XML_ErrorString(XML_GetErrorCode(p)));
+
+    XML_ParserFree (p);
+}
+
+/** \brief Parser context for configuration files. */
+struct OptConfData {
+    const char *name;
+    XML_Parser parser;
+    driOptionCache *cache;
+    int screenNum;
+    const char *driverName, *execName;
+    uint32_t ignoringDevice;
+    uint32_t ignoringApp;
+    uint32_t inDriConf;
+    uint32_t inDevice;
+    uint32_t inApp;
+    uint32_t inOption;
+};
+
+/** \brief Elements in configuration files. */
+enum OptConfElem {
+    OC_APPLICATION = 0, OC_DEVICE, OC_DRICONF, OC_OPTION, OC_COUNT
+};
+static const XML_Char *OptConfElems[] = {
+    [OC_APPLICATION]  = "application",
+    [OC_DEVICE] = "device",
+    [OC_DRICONF] = "driconf",
+    [OC_OPTION] = "option",
+};
+
+/** \brief Parse attributes of a device element. */
+static void
+parseDeviceAttr(struct OptConfData *data, const XML_Char **attr)
+{
+    uint32_t i;
+    const XML_Char *driver = NULL, *screen = NULL;
+    for (i = 0; attr[i]; i += 2) {
+        if (!strcmp (attr[i], "driver")) driver = attr[i+1];
+        else if (!strcmp (attr[i], "screen")) screen = attr[i+1];
+        else XML_WARNING("unknown device attribute: %s.", attr[i]);
+    }
+    if (driver && strcmp (driver, data->driverName))
+        data->ignoringDevice = data->inDevice;
+    else if (screen) {
+        driOptionValue screenNum;
+        if (!parseValue (&screenNum, DRI_INT, screen))
+            XML_WARNING("illegal screen number: %s.", screen);
+        else if (screenNum._int != data->screenNum)
+            data->ignoringDevice = data->inDevice;
+    }
+}
+
+/** \brief Parse attributes of an application element. */
+static void
+parseAppAttr(struct OptConfData *data, const XML_Char **attr)
+{
+    uint32_t i;
+    const XML_Char *exec = NULL;
+    for (i = 0; attr[i]; i += 2) {
+        if (!strcmp (attr[i], "name")) /* not needed here */;
+        else if (!strcmp (attr[i], "executable")) exec = attr[i+1];
+        else XML_WARNING("unknown application attribute: %s.", attr[i]);
+    }
+    if (exec && strcmp (exec, data->execName))
+        data->ignoringApp = data->inApp;
+}
+
+/** \brief Parse attributes of an option element. */
+static void
+parseOptConfAttr(struct OptConfData *data, const XML_Char **attr)
+{
+    uint32_t i;
+    const XML_Char *name = NULL, *value = NULL;
+    for (i = 0; attr[i]; i += 2) {
+        if (!strcmp (attr[i], "name")) name = attr[i+1];
+        else if (!strcmp (attr[i], "value")) value = attr[i+1];
+        else XML_WARNING("unknown option attribute: %s.", attr[i]);
+    }
+    if (!name) XML_WARNING1 ("name attribute missing in option.");
+    if (!value) XML_WARNING1 ("value attribute missing in option.");
+    if (name && value) {
+        driOptionCache *cache = data->cache;
+        uint32_t opt = findOption (cache, name);
+        if (cache->info[opt].name == NULL)
+            /* don't use XML_WARNING, drirc defines options for all drivers,
+             * but not all drivers support them */
+            return;
+        else if (getenv (cache->info[opt].name))
+          /* don't use XML_WARNING, we want the user to see this! */
+            fprintf (stderr, "ATTENTION: option value of option %s ignored.\n",
+                     cache->info[opt].name);
+        else if (!parseValue (&cache->values[opt], cache->info[opt].type, value))
+            XML_WARNING ("illegal option value: %s.", value);
+    }
+}
+
+/** \brief Handler for start element events. */
+static void
+optConfStartElem(void *userData, const XML_Char *name,
+                 const XML_Char **attr)
+{
+    struct OptConfData *data = (struct OptConfData *)userData;
+    enum OptConfElem elem = bsearchStr (name, OptConfElems, OC_COUNT);
+    switch (elem) {
+      case OC_DRICONF:
+        if (data->inDriConf)
+            XML_WARNING1 ("nested <driconf> elements.");
+        if (attr[0])
+            XML_WARNING1 ("attributes specified on <driconf> element.");
+        data->inDriConf++;
+        break;
+      case OC_DEVICE:
+        if (!data->inDriConf)
+            XML_WARNING1 ("<device> should be inside <driconf>.");
+        if (data->inDevice)
+            XML_WARNING1 ("nested <device> elements.");
+        data->inDevice++;
+        if (!data->ignoringDevice && !data->ignoringApp)
+            parseDeviceAttr (data, attr);
+        break;
+      case OC_APPLICATION:
+        if (!data->inDevice)
+            XML_WARNING1 ("<application> should be inside <device>.");
+        if (data->inApp)
+            XML_WARNING1 ("nested <application> elements.");
+        data->inApp++;
+        if (!data->ignoringDevice && !data->ignoringApp)
+            parseAppAttr (data, attr);
+        break;
+      case OC_OPTION:
+        if (!data->inApp)
+            XML_WARNING1 ("<option> should be inside <application>.");
+        if (data->inOption)
+            XML_WARNING1 ("nested <option> elements.");
+        data->inOption++;
+        if (!data->ignoringDevice && !data->ignoringApp)
+            parseOptConfAttr (data, attr);
+        break;
+      default:
+        XML_WARNING ("unknown element: %s.", name);
+    }
+}
+
+/** \brief Handler for end element events. */
+static void
+optConfEndElem(void *userData, const XML_Char *name)
+{
+    struct OptConfData *data = (struct OptConfData *)userData;
+    enum OptConfElem elem = bsearchStr (name, OptConfElems, OC_COUNT);
+    switch (elem) {
+      case OC_DRICONF:
+        data->inDriConf--;
+        break;
+      case OC_DEVICE:
+        if (data->inDevice-- == data->ignoringDevice)
+            data->ignoringDevice = 0;
+        break;
+      case OC_APPLICATION:
+        if (data->inApp-- == data->ignoringApp)
+            data->ignoringApp = 0;
+        break;
+      case OC_OPTION:
+        data->inOption--;
+        break;
+      default:
+        /* unknown element, warning was produced on start tag */;
+    }
+}
+
+/** \brief Initialize an option cache based on info */
+static void
+initOptionCache(driOptionCache *cache, const driOptionCache *info)
+{
+    unsigned i, size = 1 << info->tableSize;
+    cache->info = info->info;
+    cache->tableSize = info->tableSize;
+    cache->values = malloc((1<<info->tableSize) * sizeof (driOptionValue));
+    if (cache->values == NULL) {
+        fprintf (stderr, "%s: %d: out of memory.\n", __FILE__, __LINE__);
+        abort();
+    }
+    memcpy (cache->values, info->values,
+            (1<<info->tableSize) * sizeof (driOptionValue));
+    for (i = 0; i < size; ++i) {
+        if (cache->info[i].type == DRI_STRING)
+            XSTRDUP(cache->values[i]._string, info->values[i]._string);
+    }
+}
+
+/** \brief Parse the named configuration file */
+static void
+parseOneConfigFile(XML_Parser p)
+{
+#define BUF_SIZE 0x1000
+    struct OptConfData *data = (struct OptConfData *)XML_GetUserData (p);
+    int status;
+    int fd;
+
+    if ((fd = open (data->name, O_RDONLY)) == -1) {
+        __driUtilMessage ("Can't open configuration file %s: %s.",
+                          data->name, strerror (errno));
+        return;
+    }
+
+    while (1) {
+        int bytesRead;
+        void *buffer = XML_GetBuffer (p, BUF_SIZE);
+        if (!buffer) {
+            __driUtilMessage ("Can't allocate parser buffer.");
+            break;
+        }
+        bytesRead = read (fd, buffer, BUF_SIZE);
+        if (bytesRead == -1) {
+            __driUtilMessage ("Error reading from configuration file %s: %s.",
+                              data->name, strerror (errno));
+            break;
+        }
+        status = XML_ParseBuffer (p, bytesRead, bytesRead == 0);
+        if (!status) {
+            XML_ERROR ("%s.", XML_ErrorString(XML_GetErrorCode(p)));
+            break;
+        }
+        if (bytesRead == 0)
+            break;
+    }
+
+    close (fd);
+#undef BUF_SIZE
+}
+
+#ifndef SYSCONFDIR
+#define SYSCONFDIR "/etc"
+#endif
+
+void
+driParseConfigFiles(driOptionCache *cache, const driOptionCache *info,
+                    int screenNum, const char *driverName)
+{
+    char *filenames[2] = { SYSCONFDIR "/drirc", NULL};
+    char *home;
+    uint32_t i;
+    struct OptConfData userData;
+
+    initOptionCache (cache, info);
+
+    userData.cache = cache;
+    userData.screenNum = screenNum;
+    userData.driverName = driverName;
+    userData.execName = GET_PROGRAM_NAME();
+
+    if ((home = getenv ("HOME"))) {
+        uint32_t len = strlen (home);
+        filenames[1] = malloc(len + 7+1);
+        if (filenames[1] == NULL)
+            __driUtilMessage ("Can't allocate memory for %s/.drirc.", home);
+        else {
+            memcpy (filenames[1], home, len);
+            memcpy (filenames[1] + len, "/.drirc", 7+1);
+        }
+    }
+
+    for (i = 0; i < 2; ++i) {
+        XML_Parser p;
+        if (filenames[i] == NULL)
+            continue;
+
+        p = XML_ParserCreate (NULL); /* use encoding specified by file */
+        XML_SetElementHandler (p, optConfStartElem, optConfEndElem);
+        XML_SetUserData (p, &userData);
+        userData.parser = p;
+        userData.name = filenames[i];
+        userData.ignoringDevice = 0;
+        userData.ignoringApp = 0;
+        userData.inDriConf = 0;
+        userData.inDevice = 0;
+        userData.inApp = 0;
+        userData.inOption = 0;
+
+        parseOneConfigFile (p);
+        XML_ParserFree (p);
+    }
+
+    free(filenames[1]);
+}
+
+void
+driDestroyOptionInfo(driOptionCache *info)
+{
+    driDestroyOptionCache(info);
+    if (info->info) {
+        uint32_t i, size = 1 << info->tableSize;
+        for (i = 0; i < size; ++i) {
+            if (info->info[i].name) {
+                free(info->info[i].name);
+                free(info->info[i].ranges);
+            }
+        }
+        free(info->info);
+    }
+}
+
+void
+driDestroyOptionCache(driOptionCache *cache)
+{
+    if (cache->info) {
+        unsigned i, size = 1 << cache->tableSize;
+        for (i = 0; i < size; ++i) {
+            if (cache->info[i].type == DRI_STRING)
+                free(cache->values[i]._string);
+        }
+    }
+    free(cache->values);
+}
+
+unsigned char
+driCheckOption(const driOptionCache *cache, const char *name,
+               driOptionType type)
+{
+    uint32_t i = findOption (cache, name);
+    return cache->info[i].name != NULL && cache->info[i].type == type;
+}
+
+unsigned char
+driQueryOptionb(const driOptionCache *cache, const char *name)
+{
+    uint32_t i = findOption (cache, name);
+  /* make sure the option is defined and has the correct type */
+    assert (cache->info[i].name != NULL);
+    assert (cache->info[i].type == DRI_BOOL);
+    return cache->values[i]._bool;
+}
+
+int
+driQueryOptioni(const driOptionCache *cache, const char *name)
+{
+    uint32_t i = findOption (cache, name);
+  /* make sure the option is defined and has the correct type */
+    assert (cache->info[i].name != NULL);
+    assert (cache->info[i].type == DRI_INT || cache->info[i].type == DRI_ENUM);
+    return cache->values[i]._int;
+}
+
+float
+driQueryOptionf(const driOptionCache *cache, const char *name)
+{
+    uint32_t i = findOption (cache, name);
+  /* make sure the option is defined and has the correct type */
+    assert (cache->info[i].name != NULL);
+    assert (cache->info[i].type == DRI_FLOAT);
+    return cache->values[i]._float;
+}
+
+char *
+driQueryOptionstr(const driOptionCache *cache, const char *name)
+{
+    uint32_t i = findOption (cache, name);
+  /* make sure the option is defined and has the correct type */
+    assert (cache->info[i].name != NULL);
+    assert (cache->info[i].type == DRI_STRING);
+    return cache->values[i]._string;
+}