util.c

/* Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/*
 * util.c: string utility things
 *
 * 3/21/93 Rob McCool
 * 1995-96 Many changes by the Apache Software Foundation
 *
 */

/* Debugging aid:
 * #define DEBUG            to trace all cfg_open*()/cfg_closefile() calls
 * #define DEBUG_CFG_LINES  to trace every line read from the config files
 */

#include "apr.h"
#include "apr_strings.h"
#include "apr_lib.h"

#define APR_WANT_STDIO
#define APR_WANT_STRFUNC
#include "apr_want.h"

#if APR_HAVE_UNISTD_H
#include <unistd.h>
#endif
#if APR_HAVE_PROCESS_H
#include <process.h>            /* for getpid() on Win32 */
#endif
#if APR_HAVE_NETDB_H
#include <netdb.h>              /* for gethostbyname() */
#endif

#include "ap_config.h"
#include "apr_base64.h"
#include "httpd.h"
#include "http_main.h"
#include "http_log.h"
#include "http_protocol.h"
#include "http_config.h"
#include "http_core.h"
#include "util_ebcdic.h"
#include "util_varbuf.h"

#ifdef HAVE_PWD_H
#include <pwd.h>
#endif
#ifdef HAVE_GRP_H
#include <grp.h>
#endif
#ifdef HAVE_SYS_LOADAVG_H
#include <sys/loadavg.h>
#endif

#include "ap_mpm.h"

/* A bunch of functions in util.c scan strings looking for certain characters.
 * To make that more efficient we encode a lookup table.  The test_char_table
 * is generated automatically by gen_test_char.c.
 */
#include "test_char.h"

/* we assume the folks using this ensure 0 <= c < 256... which means
 * you need a cast to (unsigned char) first, you can't just plug a
 * char in here and get it to work, because if char is signed then it
 * will first be sign extended.
 */
#define TEST_CHAR(c, f)        (test_char_table[(unsigned char)(c)] & (f))

/* Win32/NetWare/OS2 need to check for both forward and back slashes
 * in ap_getparents() and ap_escape_url.
 */
#ifdef CASE_BLIND_FILESYSTEM
#define IS_SLASH(s) ((s == '/') || (s == '\\'))
#define SLASHES "/\\"
#else
#define IS_SLASH(s) (s == '/')
#define SLASHES "/"
#endif

/* we know core's module_index is 0 */
#undef APLOG_MODULE_INDEX
#define APLOG_MODULE_INDEX AP_CORE_MODULE_INDEX

/*
 * Examine a field value (such as a media-/content-type) string and return
 * it sans any parameters; e.g., strip off any ';charset=foo' and the like.
 */
AP_DECLARE(char *) ap_field_noparam(apr_pool_t *p, const char *intype)
{
    const char *semi;

    if (intype == NULL) return NULL;

    semi = ap_strchr_c(intype, ';');
    if (semi == NULL) {
        return apr_pstrdup(p, intype);
    }
    else {
        while ((semi > intype) && apr_isspace(semi[-1])) {
            semi--;
        }
        return apr_pstrmemdup(p, intype, semi - intype);
    }
}

AP_DECLARE(char *) ap_ht_time(apr_pool_t *p, apr_time_t t, const char *fmt,
                              int gmt)
{
    apr_size_t retcode;
    char ts[MAX_STRING_LEN];
    char tf[MAX_STRING_LEN];
    apr_time_exp_t xt;

    if (gmt) {
        const char *f;
        char *strp;

        apr_time_exp_gmt(&xt, t);
        /* Convert %Z to "GMT" and %z to "+0000";
         * on hosts that do not have a time zone string in struct tm,
         * strftime must assume its argument is local time.
         */
        for(strp = tf, f = fmt; strp < tf + sizeof(tf) - 6 && (*strp = *f)
            ; f++, strp++) {
            if (*f != '%') continue;
            switch (f[1]) {
            case '%':
                *++strp = *++f;
                break;
            case 'Z':
                *strp++ = 'G';
                *strp++ = 'M';
                *strp = 'T';
                f++;
                break;
            case 'z': /* common extension */
                *strp++ = '+';
                *strp++ = '0';
                *strp++ = '0';
                *strp++ = '0';
                *strp = '0';
                f++;
                break;
            }
        }
        *strp = '\0';
        fmt = tf;
    }
    else {
        apr_time_exp_lt(&xt, t);
    }

    /* check return code? */
    apr_strftime(ts, &retcode, MAX_STRING_LEN, fmt, &xt);
    ts[MAX_STRING_LEN - 1] = '\0';
    return apr_pstrdup(p, ts);
}

/* Roy owes Rob beer. */
/* Rob owes Roy dinner. */

/* These legacy comments would make a lot more sense if Roy hadn't
 * replaced the old later_than() routine with util_date.c.
 *
 * Well, okay, they still wouldn't make any sense.
 */

/* Match = 0, NoMatch = 1, Abort = -1
 * Based loosely on sections of wildmat.c by Rich Salz
 * Hmmm... shouldn't this really go component by component?
 */
AP_DECLARE(int) ap_strcmp_match(const char *str, const char *expected)
{
    int x, y;

    for (x = 0, y = 0; expected[y]; ++y, ++x) {
        if ((!str[x]) && (expected[y] != '*'))
            return -1;
        if (expected[y] == '*') {
            while (expected[++y] == '*');
            if (!expected[y])
                return 0;
            while (str[x]) {
                int ret;
                if ((ret = ap_strcmp_match(&str[x++], &expected[y])) != 1)
                    return ret;
            }
            return -1;
        }
        else if ((expected[y] != '?') && (str[x] != expected[y]))
            return 1;
    }
    return (str[x] != '\0');
}

AP_DECLARE(int) ap_strcasecmp_match(const char *str, const char *expected)
{
    int x, y;

    for (x = 0, y = 0; expected[y]; ++y, ++x) {
        if (!str[x] && expected[y] != '*')
            return -1;
        if (expected[y] == '*') {
            while (expected[++y] == '*');
            if (!expected[y])
                return 0;
            while (str[x]) {
                int ret;
                if ((ret = ap_strcasecmp_match(&str[x++], &expected[y])) != 1)
                    return ret;
            }
            return -1;
        }
        else if (expected[y] != '?'
                 && apr_tolower(str[x]) != apr_tolower(expected[y]))
            return 1;
    }
    return (str[x] != '\0');
}

/* We actually compare the canonical root to this root, (but we don't
 * waste time checking the case), since every use of this function in
 * httpd-2.1 tests if the path is 'proper', meaning we've already passed
 * it through apr_filepath_merge, or we haven't.
 */
AP_DECLARE(int) ap_os_is_path_absolute(apr_pool_t *p, const char *dir)
{
    const char *newpath;
    const char *ourdir = dir;
    if (apr_filepath_root(&newpath, &dir, 0, p) != APR_SUCCESS
            || strncmp(newpath, ourdir, strlen(newpath)) != 0) {
        return 0;
    }
    return 1;
}

AP_DECLARE(int) ap_is_matchexp(const char *str)
{
    int x;

    for (x = 0; str[x]; x++)
        if ((str[x] == '*') || (str[x] == '?'))
            return 1;
    return 0;
}

/*
 * Here's a pool-based interface to the POSIX-esque ap_regcomp().
 * Note that we return ap_regex_t instead of being passed one.
 * The reason is that if you use an already-used ap_regex_t structure,
 * the memory that you've already allocated gets forgotten, and
 * regfree() doesn't clear it. So we don't allow it.
 */

static apr_status_t regex_cleanup(void *preg)
{
    ap_regfree((ap_regex_t *) preg);
    return APR_SUCCESS;
}

AP_DECLARE(ap_regex_t *) ap_pregcomp(apr_pool_t *p, const char *pattern,
                                     int cflags)
{
    ap_regex_t *preg = apr_palloc(p, sizeof *preg);
    int err = ap_regcomp(preg, pattern, cflags);
    if (err) {
        if (err == AP_REG_ESPACE)
            ap_abort_on_oom();
        return NULL;
    }

    apr_pool_cleanup_register(p, (void *) preg, regex_cleanup,
                              apr_pool_cleanup_null);

    return preg;
}

AP_DECLARE(void) ap_pregfree(apr_pool_t *p, ap_regex_t *reg)
{
    ap_regfree(reg);
    apr_pool_cleanup_kill(p, (void *) reg, regex_cleanup);
}

/*
 * Similar to standard strstr() but we ignore case in this version.
 * Based on the strstr() implementation further below.
 */
AP_DECLARE(char *) ap_strcasestr(const char *s1, const char *s2)
{
    char *p1, *p2;
    if (*s2 == '\0') {
        /* an empty s2 */
        return((char *)s1);
    }
    while(1) {
        for ( ; (*s1 != '\0') && (apr_tolower(*s1) != apr_tolower(*s2)); s1++);
        if (*s1 == '\0') {
            return(NULL);
        }
        /* found first character of s2, see if the rest matches */
        p1 = (char *)s1;
        p2 = (char *)s2;
        for (++p1, ++p2; apr_tolower(*p1) == apr_tolower(*p2); ++p1, ++p2) {
            if (*p1 == '\0') {
                /* both strings ended together */
                return((char *)s1);
            }
        }
        if (*p2 == '\0') {
            /* second string ended, a match */
            break;
        }
        /* didn't find a match here, try starting at next character in s1 */
        s1++;
    }
    return((char *)s1);
}

/*
 * Returns an offsetted pointer in bigstring immediately after
 * prefix. Returns bigstring if bigstring doesn't start with
 * prefix or if prefix is longer than bigstring while still matching.
 * NOTE: pointer returned is relative to bigstring, so we
 * can use standard pointer comparisons in the calling function
 * (eg: test if ap_stripprefix(a,b) == a)
 */
AP_DECLARE(const char *) ap_stripprefix(const char *bigstring,
                                        const char *prefix)
{
    const char *p1;

    if (*prefix == '\0')
        return bigstring;

    p1 = bigstring;
    while (*p1 && *prefix) {
        if (*p1++ != *prefix++)
            return bigstring;
    }
    if (*prefix == '\0')
        return p1;

    /* hit the end of bigstring! */
    return bigstring;
}

/* This function substitutes for $0-$9, filling in regular expression
 * submatches. Pass it the same nmatch and pmatch arguments that you
 * passed ap_regexec(). pmatch should not be greater than the maximum number
 * of subexpressions - i.e. one more than the re_nsub member of ap_regex_t.
 *
 * nmatch must be <=AP_MAX_REG_MATCH (10).
 *
 * input should be the string with the $-expressions, source should be the
 * string that was matched against.
 *
 * It returns the substituted string, or NULL if a vbuf is used.
 * On errors, returns the orig string.
 *
 * Parts of this code are based on Henry Spencer's regsub(), from his
 * AT&T V8 regexp package.
 */

static apr_status_t regsub_core(apr_pool_t *p, char **result,
                                struct ap_varbuf *vb, const char *input,
                                const char *source, apr_size_t nmatch,
                                ap_regmatch_t pmatch[], apr_size_t maxlen)
{
    const char *src = input;
    char *dst;
    char c;
    apr_size_t no;
    apr_size_t len = 0;

    AP_DEBUG_ASSERT((result && p && !vb) || (vb && !p && !result));
    if (!source || nmatch>AP_MAX_REG_MATCH)
        return APR_EINVAL;
    if (!nmatch) {
        len = strlen(src);
        if (maxlen > 0 && len >= maxlen)
            return APR_ENOMEM;
        if (!vb) {
            *result = apr_pstrmemdup(p, src, len);
            return APR_SUCCESS;
        }
        else {
            ap_varbuf_strmemcat(vb, src, len);
            return APR_SUCCESS;
        }
    }

    /* First pass, find the size */
    while ((c = *src++) != '\0') {
        if (c == '$' && apr_isdigit(*src))
            no = *src++ - '0';
        else
            no = AP_MAX_REG_MATCH;

        if (no >= AP_MAX_REG_MATCH) {  /* Ordinary character. */
            if (c == '\\' && *src)
                src++;
            len++;
        }
        else if (no < nmatch && pmatch[no].rm_so < pmatch[no].rm_eo) {
            if (APR_SIZE_MAX - len <= pmatch[no].rm_eo - pmatch[no].rm_so)
                return APR_ENOMEM;
            len += pmatch[no].rm_eo - pmatch[no].rm_so;
        }

    }

    if (len >= maxlen && maxlen > 0)
        return APR_ENOMEM;

    if (!vb) {
        *result = dst = apr_palloc(p, len + 1);
    }
    else {
        if (vb->strlen == AP_VARBUF_UNKNOWN)
            vb->strlen = strlen(vb->buf);
        ap_varbuf_grow(vb, vb->strlen + len);
        dst = vb->buf + vb->strlen;
        vb->strlen += len;
    }

    /* Now actually fill in the string */

    src = input;

    while ((c = *src++) != '\0') {
        if (c == '$' && apr_isdigit(*src))
            no = *src++ - '0';
        else
            no = AP_MAX_REG_MATCH;

        if (no >= AP_MAX_REG_MATCH) {  /* Ordinary character. */
            if (c == '\\' && *src)
                c = *src++;
            *dst++ = c;
        }
        else if (no < nmatch && pmatch[no].rm_so < pmatch[no].rm_eo) {
            len = pmatch[no].rm_eo - pmatch[no].rm_so;
            memcpy(dst, source + pmatch[no].rm_so, len);
            dst += len;
        }

    }
    *dst = '\0';

    return APR_SUCCESS;
}

#ifndef AP_PREGSUB_MAXLEN
#define AP_PREGSUB_MAXLEN   (HUGE_STRING_LEN * 8)
#endif
AP_DECLARE(char *) ap_pregsub(apr_pool_t *p, const char *input,
                              const char *source, apr_size_t nmatch,
                              ap_regmatch_t pmatch[])
{
    char *result;
    apr_status_t rc = regsub_core(p, &result, NULL, input, source, nmatch,
                                  pmatch, AP_PREGSUB_MAXLEN);
    if (rc != APR_SUCCESS)
        result = NULL;
    return result;
}

AP_DECLARE(apr_status_t) ap_pregsub_ex(apr_pool_t *p, char **result,
                                       const char *input, const char *source,
                                       apr_size_t nmatch, ap_regmatch_t pmatch[],
                                       apr_size_t maxlen)
{
    apr_status_t rc = regsub_core(p, result, NULL, input, source, nmatch,
                                  pmatch, maxlen);
    if (rc != APR_SUCCESS)
        *result = NULL;
    return rc;
}

/*
 * Parse .. so we don't compromise security
 */
AP_DECLARE(void) ap_getparents(char *name)
{
    char *next;
    int l, w, first_dot;

    /* Four paseses, as per RFC 1808 */
    /* a) remove ./ path segments */
    for (next = name; *next && (*next != '.'); next++) {
    }

    l = w = first_dot = next - name;
    while (name[l] != '\0') {
        if (name[l] == '.' && IS_SLASH(name[l + 1])
            && (l == 0 || IS_SLASH(name[l - 1])))
            l += 2;
        else
            name[w++] = name[l++];
    }

    /* b) remove trailing . path, segment */
    if (w == 1 && name[0] == '.')
        w--;
    else if (w > 1 && name[w - 1] == '.' && IS_SLASH(name[w - 2]))
        w--;
    name[w] = '\0';

    /* c) remove all xx/../ segments. (including leading ../ and /../) */
    l = first_dot;

    while (name[l] != '\0') {
        if (name[l] == '.' && name[l + 1] == '.' && IS_SLASH(name[l + 2])
            && (l == 0 || IS_SLASH(name[l - 1]))) {
            int m = l + 3, n;

            l = l - 2;
            if (l >= 0) {
                while (l >= 0 && !IS_SLASH(name[l]))
                    l--;
                l++;
            }
            else
                l = 0;
            n = l;
            while ((name[n] = name[m]))
                (++n, ++m);
        }
        else
            ++l;
    }

    /* d) remove trailing xx/.. segment. */
    if (l == 2 && name[0] == '.' && name[1] == '.')
        name[0] = '\0';
    else if (l > 2 && name[l - 1] == '.' && name[l - 2] == '.'
             && IS_SLASH(name[l - 3])) {
        l = l - 4;
        if (l >= 0) {
            while (l >= 0 && !IS_SLASH(name[l]))
                l--;
            l++;
        }
        else
            l = 0;
        name[l] = '\0';
    }
}

AP_DECLARE(void) ap_no2slash(char *name)
{
    char *d, *s;

    s = d = name;

#ifdef HAVE_UNC_PATHS
    /* Check for UNC names.  Leave leading two slashes. */
    if (s[0] == '/' && s[1] == '/')
        *d++ = *s++;
#endif

    while (*s) {
        if ((*d++ = *s) == '/') {
            do {
                ++s;
            } while (*s == '/');
        }
        else {
            ++s;
        }
    }
    *d = '\0';
}


/*
 * copy at most n leading directories of s into d
 * d should be at least as large as s plus 1 extra byte
 * assumes n > 0
 * the return value is the ever useful pointer to the trailing \0 of d
 *
 * MODIFIED FOR HAVE_DRIVE_LETTERS and NETWARE environments,
 * so that if n == 0, "/" is returned in d with n == 1
 * and s == "e:/test.html", "e:/" is returned in d
 * *** See also directory_walk in modules/http/http_request.c

 * examples:
 *    /a/b, 0  ==> /  (true for all platforms)
 *    /a/b, 1  ==> /
 *    /a/b, 2  ==> /a/
 *    /a/b, 3  ==> /a/b/
 *    /a/b, 4  ==> /a/b/
 *
 *    c:/a/b 0 ==> /
 *    c:/a/b 1 ==> c:/
 *    c:/a/b 2 ==> c:/a/
 *    c:/a/b 3 ==> c:/a/b
 *    c:/a/b 4 ==> c:/a/b
 */
AP_DECLARE(char *) ap_make_dirstr_prefix(char *d, const char *s, int n)
{
    if (n < 1) {
        *d = '/';
        *++d = '\0';
        return (d);
    }

    for (;;) {
        if (*s == '\0' || (*s == '/' && (--n) == 0)) {
            *d = '/';
            break;
        }
        *d++ = *s++;
    }
    *++d = 0;
    return (d);
}


/*
 * return the parent directory name including trailing / of the file s
 */
AP_DECLARE(char *) ap_make_dirstr_parent(apr_pool_t *p, const char *s)
{
    const char *last_slash = ap_strrchr_c(s, '/');
    char *d;
    int l;

    if (last_slash == NULL) {
        return apr_pstrdup(p, "");
    }
    l = (last_slash - s) + 1;
    d = apr_pstrmemdup(p, s, l);

    return (d);
}


AP_DECLARE(int) ap_count_dirs(const char *path)
{
    int x, n;

    for (x = 0, n = 0; path[x]; x++)
        if (path[x] == '/')
            n++;
    return n;
}

AP_DECLARE(char *) ap_getword_nc(apr_pool_t *atrans, char **line, char stop)
{
    return ap_getword(atrans, (const char **) line, stop);
}

AP_DECLARE(char *) ap_getword(apr_pool_t *atrans, const char **line, char stop)
{
    const char *pos = *line;
    int len;
    char *res;

    while ((*pos != stop) && *pos) {
        ++pos;
    }

    len = pos - *line;
    res = apr_pstrmemdup(atrans, *line, len);

    if (stop) {
        while (*pos == stop) {
            ++pos;
        }
    }
    *line = pos;

    return res;
}

AP_DECLARE(char *) ap_getword_white_nc(apr_pool_t *atrans, char **line)
{
    return ap_getword_white(atrans, (const char **) line);
}

AP_DECLARE(char *) ap_getword_white(apr_pool_t *atrans, const char **line)
{
    const char *pos = *line;
    int len;
    char *res;

    while (!apr_isspace(*pos) && *pos) {
        ++pos;
    }

    len = pos - *line;
    res = apr_pstrmemdup(atrans, *line, len);

    while (apr_isspace(*pos)) {
        ++pos;
    }

    *line = pos;

    return res;
}

AP_DECLARE(char *) ap_getword_nulls_nc(apr_pool_t *atrans, char **line,
                                       char stop)
{
    return ap_getword_nulls(atrans, (const char **) line, stop);
}

AP_DECLARE(char *) ap_getword_nulls(apr_pool_t *atrans, const char **line,
                                    char stop)
{
    const char *pos = ap_strchr_c(*line, stop);
    char *res;

    if (!pos) {
        apr_size_t len = strlen(*line);
        res = apr_pstrmemdup(atrans, *line, len);
        *line += len;
        return res;
    }

    res = apr_pstrmemdup(atrans, *line, pos - *line);

    ++pos;

    *line = pos;

    return res;
}

/* Get a word, (new) config-file style --- quoted strings and backslashes
 * all honored
 */

static char *substring_conf(apr_pool_t *p, const char *start, int len,
                            char quote)
{
    char *result = apr_palloc(p, len + 1);
    char *resp = result;
    int i;

    for (i = 0; i < len; ++i) {
        if (start[i] == '\\' && (start[i + 1] == '\\'
                                 || (quote && start[i + 1] == quote)))
            *resp++ = start[++i];
        else
            *resp++ = start[i];
    }

    *resp++ = '\0';
#if RESOLVE_ENV_PER_TOKEN
    return (char *)ap_resolve_env(p,result);
#else
    return result;
#endif
}

AP_DECLARE(char *) ap_getword_conf_nc(apr_pool_t *p, char **line)
{
    return ap_getword_conf(p, (const char **) line);
}

AP_DECLARE(char *) ap_getword_conf(apr_pool_t *p, const char **line)
{
    const char *str = *line, *strend;
    char *res;
    char quote;

    while (apr_isspace(*str))
        ++str;

    if (!*str) {
        *line = str;
        return "";
    }

    if ((quote = *str) == '"' || quote == '\'') {
        strend = str + 1;
        while (*strend && *strend != quote) {
            if (*strend == '\\' && strend[1] &&
                (strend[1] == quote || strend[1] == '\\')) {
                strend += 2;
            }
            else {
                ++strend;
            }
        }
        res = substring_conf(p, str + 1, strend - str - 1, quote);

        if (*strend == quote)
            ++strend;
    }
    else {
        strend = str;
        while (*strend && !apr_isspace(*strend))
            ++strend;

        res = substring_conf(p, str, strend - str, 0);
    }

    while (apr_isspace(*strend))
        ++strend;
    *line = strend;
    return res;
}

AP_DECLARE(char *) ap_getword_conf2_nc(apr_pool_t *p, char **line)
{
    return ap_getword_conf2(p, (const char **) line);
}

AP_DECLARE(char *) ap_getword_conf2(apr_pool_t *p, const char **line)
{
    const char *str = *line, *strend;
    char *res;
    char quote;
    int count = 1;

    while (apr_isspace(*str))
        ++str;

    if (!*str) {
        *line = str;
        return "";
    }

    if ((quote = *str) == '"' || quote == '\'')
        return ap_getword_conf(p, line);

    if (quote == '{') {
        strend = str + 1;
        while (*strend) {
            if (*strend == '}' && !--count)
                break;
            if (*strend == '{')
                ++count;
            if (*strend == '\\' && strend[1] && strend[1] == '\\') {
                ++strend;
            }
            ++strend;
        }
        res = substring_conf(p, str + 1, strend - str - 1, 0);

        if (*strend == '}')
            ++strend;
    }
    else {
        strend = str;
        while (*strend && !apr_isspace(*strend))
            ++strend;

        res = substring_conf(p, str, strend - str, 0);
    }

    while (apr_isspace(*strend))
        ++strend;
    *line = strend;
    return res;
}

AP_DECLARE(int) ap_cfg_closefile(ap_configfile_t *cfp)
{
#ifdef DEBUG
    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, NULL, APLOGNO(00551)
        "Done with config file %s", cfp->name);
#endif
    return (cfp->close == NULL) ? 0 : cfp->close(cfp->param);
}

/* we can't use apr_file_* directly because of linking issues on Windows */
static apr_status_t cfg_close(void *param)
{
    return apr_file_close(param);
}

static apr_status_t cfg_getch(char *ch, void *param)
{
    return apr_file_getc(ch, param);
}

static apr_status_t cfg_getstr(void *buf, apr_size_t bufsiz, void *param)
{
    return apr_file_gets(buf, bufsiz, param);
}

/* Open a ap_configfile_t as FILE, return open ap_configfile_t struct pointer */
AP_DECLARE(apr_status_t) ap_pcfg_openfile(ap_configfile_t **ret_cfg,
                                          apr_pool_t *p, const char *name)
{
    ap_configfile_t *new_cfg;
    apr_file_t *file = NULL;
    apr_finfo_t finfo;
    apr_status_t status;
#ifdef DEBUG
    char buf[120];
#endif

    if (name == NULL) {
        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL, APLOGNO(00552)
               "Internal error: pcfg_openfile() called with NULL filename");
        return APR_EBADF;
    }

    status = apr_file_open(&file, name, APR_READ | APR_BUFFERED,
                           APR_OS_DEFAULT, p);
#ifdef DEBUG
    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, NULL, APLOGNO(00553)
                "Opening config file %s (%s)",
                name, (status != APR_SUCCESS) ?
                apr_strerror(status, buf, sizeof(buf)) : "successful");
#endif
    if (status != APR_SUCCESS)
        return status;

    status = apr_file_info_get(&finfo, APR_FINFO_TYPE, file);
    if (status != APR_SUCCESS)
        return status;

    if (finfo.filetype != APR_REG &&
#if defined(WIN32) || defined(OS2) || defined(NETWARE)
        strcasecmp(apr_filepath_name_get(name), "nul") != 0) {
#else
        strcmp(name, "/dev/null") != 0) {
#endif /* WIN32 || OS2 */
        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL, APLOGNO(00554)
                     "Access to file %s denied by server: not a regular file",
                     name);
        apr_file_close(file);
        return APR_EBADF;
    }

#ifdef WIN32
    /* Some twisted character [no pun intended] at MS decided that a
     * zero width joiner as the lead wide character would be ideal for
     * describing Unicode text files.  This was further convoluted to
     * another MSism that the same character mapped into utf-8, EF BB BF
     * would signify utf-8 text files.
     *
     * Since MS configuration files are all protecting utf-8 encoded
     * Unicode path, file and resource names, we already have the correct
     * WinNT encoding.  But at least eat the stupid three bytes up front.
     */
    {
        unsigned char buf[4];
        apr_size_t len = 3;
        status = apr_file_read(file, buf, &len);
        if ((status != APR_SUCCESS) || (len < 3)
              || memcmp(buf, "\xEF\xBB\xBF", 3) != 0) {
            apr_off_t zero = 0;
            apr_file_seek(file, APR_SET, &zero);
        }
    }
#endif

    new_cfg = apr_palloc(p, sizeof(*new_cfg));
    new_cfg->param = file;
    new_cfg->name = apr_pstrdup(p, name);
    new_cfg->getch = cfg_getch;
    new_cfg->getstr = cfg_getstr;
    new_cfg->close = cfg_close;
    new_cfg->line_number = 0;
    *ret_cfg = new_cfg;
    return APR_SUCCESS;
}


/* Allocate a ap_configfile_t handle with user defined functions and params */
AP_DECLARE(ap_configfile_t *) ap_pcfg_open_custom(
            apr_pool_t *p, const char *descr, void *param,
            apr_status_t (*getc_func) (char *ch, void *param),
            apr_status_t (*gets_func) (void *buf, apr_size_t bufsize, void *param),
            apr_status_t (*close_func) (void *param))
{
    ap_configfile_t *new_cfg = apr_palloc(p, sizeof(*new_cfg));
    new_cfg->param = param;
    new_cfg->name = descr;
    new_cfg->getch = getc_func;
    new_cfg->getstr = gets_func;
    new_cfg->close = close_func;
    new_cfg->line_number = 0;
    return new_cfg;
}

/* Read one character from a configfile_t */