/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2000-2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 * Portions of this software are based upon public domain software
 * originally written at the National Center for Supercomputing Applications,
 * University of Illinois, Urbana-Champaign.
 */

/*
 * mod_autoindex.c: Handles the on-the-fly html index generation
 * 
 * Rob McCool
 * 3/23/93
 * 
 * Adapted to Apache by rst.
 *
 * Version sort added by Martin Pool <mbp@humbug.org.au>.
 */

#include "apr_strings.h"
#include "apr_fnmatch.h"
#include "apr_strings.h"
#include "apr_lib.h"

#define APR_WANT_STRFUNC
#include "apr_want.h"

#include "ap_config.h"
#include "httpd.h"
#include "http_config.h"
#include "http_core.h"
#include "http_request.h"
#include "http_protocol.h"
#include "http_log.h"
#include "http_main.h"
#include "util_script.h"

#include "mod_core.h"

module AP_MODULE_DECLARE_DATA autoindex_module;

/****************************************************************
 *
 * Handling configuration directives...
 */

#define HRULE 1
#define NO_HRULE 0
#define FRONT_MATTER 1
#define END_MATTER 0

#define FANCY_INDEXING 1	/* Indexing options */
#define ICONS_ARE_LINKS 2
#define SCAN_HTML_TITLES 4
#define SUPPRESS_LAST_MOD 8
#define SUPPRESS_SIZE 16
#define SUPPRESS_DESC 32
#define SUPPRESS_PREAMBLE 64
#define SUPPRESS_COLSORT 128
#define NO_OPTIONS 256
#define VERSION_SORT	512

#define K_PAD 1
#define K_NOPAD 0

#define K_NOADJUST 0
#define K_ADJUST 1
#define K_UNSET 2

/*
 * Define keys for sorting.
 */
#define K_NAME 'N'		/* Sort by file name (default) */
#define K_LAST_MOD 'M'		/* Last modification date */
#define K_SIZE 'S'		/* Size (absolute, not as displayed) */
#define K_DESC 'D'		/* Description */

#define D_ASCENDING 'A'
#define D_DESCENDING 'D'

/*
 * These are the dimensions of the default icons supplied with Apache.
 */
#define DEFAULT_ICON_WIDTH 20
#define DEFAULT_ICON_HEIGHT 22

/*
 * Other default dimensions.
 */
#define DEFAULT_NAME_WIDTH 23

struct item {
    char *type;
    char *apply_to;
    char *apply_path;
    char *data;
};

typedef struct ai_desc_t {
    char *pattern;
    char *description;
    int full_path;
    int wildcards;
} ai_desc_t;

typedef struct autoindex_config_struct {

    char *default_icon;
    int opts;
    int incremented_opts;
    int decremented_opts;
    int name_width;
    int name_adjust;
    int icon_width;
    int icon_height;
    char *default_order;

    apr_array_header_t *icon_list;
    apr_array_header_t *alt_list;
    apr_array_header_t *desc_list;
    apr_array_header_t *ign_list;
    apr_array_header_t *hdr_list;
    apr_array_header_t *rdme_list;

} autoindex_config_rec;

static char c_by_encoding, c_by_type, c_by_path;

#define BY_ENCODING &c_by_encoding
#define BY_TYPE &c_by_type
#define BY_PATH &c_by_path

/*
 * Return true if the specified string refers to the parent directory (i.e.,
 * matches ".." or "../").  Hopefully this one call is significantly less
 * expensive than multiple strcmp() calls.
 */
static APR_INLINE int is_parent(const char *name)
{
    /*
     * Now, IFF the first two bytes are dots, and the third byte is either
     * EOS (\0) or a slash followed by EOS, we have a match.
     */
    if (((name[0] == '.') && (name[1] == '.'))
	&& ((name[2] == '\0')
	    || ((name[2] == '/') && (name[3] == '\0')))) {
        return 1;
    }
    return 0;
}

/*
 * This routine puts the standard HTML header at the top of the index page.
 * We include the DOCTYPE because we may be using features therefrom (i.e.,
 * HEIGHT and WIDTH attributes on the icons if we're FancyIndexing).
 */
static void emit_preamble(request_rec *r, char *title)
{
    ap_rvputs(r, DOCTYPE_HTML_3_2,
	      "<HTML>\n <HEAD>\n  <TITLE>Index of ", title,
	      "</TITLE>\n </HEAD>\n <BODY>\n", NULL);
}

static void push_item(apr_array_header_t *arr, char *type, const char *to,
		      const char *path, const char *data)
{
    struct item *p = (struct item *) apr_array_push(arr);

    if (!to) {
	to = "";
    }
    if (!path) {
	path = "";
    }

    p->type = type;
    p->data = data ? apr_pstrdup(arr->cont, data) : NULL;
    p->apply_path = apr_pstrcat(arr->cont, path, "*", NULL);

    if ((type == BY_PATH) && (!ap_is_matchexp(to))) {
	p->apply_to = apr_pstrcat(arr->cont, "*", to, NULL);
    }
    else if (to) {
	p->apply_to = apr_pstrdup(arr->cont, to);
    }
    else {
	p->apply_to = NULL;
    }
}

static const char *add_alt(cmd_parms *cmd, void *d, const char *alt,
			   const char *to)
{
    if (cmd->info == BY_PATH) {
        if (!strcmp(to, "**DIRECTORY**")) {
	    to = "^^DIRECTORY^^";
	}
    }
    if (cmd->info == BY_ENCODING) {
        char *tmp = apr_pstrdup(cmd->pool, to);
	ap_str_tolower(tmp);
	to = tmp;
    }

    push_item(((autoindex_config_rec *) d)->alt_list, cmd->info, to,
	      cmd->path, alt);
    return NULL;
}

static const char *add_icon(cmd_parms *cmd, void *d, const char *icon,
			    const char *to)
{
    char *iconbak = apr_pstrdup(cmd->pool, icon);

    if (icon[0] == '(') {
	char *alt;
	char *cl = strchr(iconbak, ')');

	if (cl == NULL) {
	    return "missing closing paren";
	}
	alt = ap_getword_nc(cmd->pool, &iconbak, ',');
	*cl = '\0';				/* Lose closing paren */
	add_alt(cmd, d, &alt[1], to);
    }
    if (cmd->info == BY_PATH) {
        if (!strcmp(to, "**DIRECTORY**")) {
	    to = "^^DIRECTORY^^";
	}
    }
    if (cmd->info == BY_ENCODING) {
        char *tmp = apr_pstrdup(cmd->pool, to);
	ap_str_tolower(tmp);
	to = tmp;
    }

    push_item(((autoindex_config_rec *) d)->icon_list, cmd->info, to,
	      cmd->path, iconbak);
    return NULL;
}

/*
 * Add description text for a filename pattern.  If the pattern has
 * wildcards already (or we need to add them), add leading and
 * trailing wildcards to it to ensure substring processing.  If the
 * pattern contains a '/' anywhere, force wildcard matching mode,
 * add a slash to the prefix so that "bar/bletch" won't be matched
 * by "foobar/bletch", and make a note that there's a delimiter;
 * the matching routine simplifies to just the actual filename
 * whenever it can.  This allows definitions in parent directories
 * to be made for files in subordinate ones using relative paths.
 */

/*
 * Absent a strcasestr() function, we have to force wildcards on
 * systems for which "AAA" and "aaa" mean the same file.
 */
#ifdef CASE_BLIND_FILESYSTEM
#define WILDCARDS_REQUIRED 1
#else
#define WILDCARDS_REQUIRED 0
#endif

static const char *add_desc(cmd_parms *cmd, void *d, const char *desc,
			    const char *to)
{
    autoindex_config_rec *dcfg = (autoindex_config_rec *) d;
    ai_desc_t *desc_entry;
    char *prefix = "";

    desc_entry = (ai_desc_t *) apr_array_push(dcfg->desc_list);
    desc_entry->full_path = (ap_strchr_c(to, '/') == NULL) ? 0 : 1;
    desc_entry->wildcards = (WILDCARDS_REQUIRED
			     || desc_entry->full_path
			     || apr_is_fnmatch(to));
    if (desc_entry->wildcards) {
	prefix = desc_entry->full_path ? "*/" : "*";
	desc_entry->pattern = apr_pstrcat(dcfg->desc_list->cont,
					 prefix, to, "*", NULL);
    }
    else {
	desc_entry->pattern = apr_pstrdup(dcfg->desc_list->cont, to);
    }
    desc_entry->description = apr_pstrdup(dcfg->desc_list->cont, desc);
    return NULL;
}

static const char *add_ignore(cmd_parms *cmd, void *d, const char *ext)
{
    push_item(((autoindex_config_rec *) d)->ign_list, 0, ext, cmd->path, NULL);
    return NULL;
}

static const char *add_header(cmd_parms *cmd, void *d, const char *name)
{
    push_item(((autoindex_config_rec *) d)->hdr_list, 0, NULL, cmd->path,
	      name);
    return NULL;
}

static const char *add_readme(cmd_parms *cmd, void *d, const char *name)
{
    push_item(((autoindex_config_rec *) d)->rdme_list, 0, NULL, cmd->path,
	      name);
    return NULL;
}

/* A legacy directive, FancyIndexing is superseded by the IndexOptions
 * keyword.  But for compatibility..
 */
static const char *fancy_indexing(cmd_parms *cmd, void *d, int arg)
{
    int curopts;
    int newopts;
    autoindex_config_rec *cfg;

    cfg = (autoindex_config_rec *) d;
    curopts = cfg->opts;
    if (curopts & NO_OPTIONS) {
	return "FancyIndexing directive conflicts with existing "
	       "IndexOptions None";
    }
    newopts = (arg ? (curopts | FANCY_INDEXING) : (curopts & ~FANCY_INDEXING));
    cfg->opts = newopts;
    return NULL;
}

static const char *add_opts(cmd_parms *cmd, void *d, const char *optstr)
{
    char *w;
    int opts;
    int opts_add;
    int opts_remove;
    char action;
    autoindex_config_rec *d_cfg = (autoindex_config_rec *) d;

    opts = d_cfg->opts;
    opts_add = d_cfg->incremented_opts;
    opts_remove = d_cfg->decremented_opts;
    while (optstr[0]) {
	int option = 0;

	w = ap_getword_conf(cmd->pool, &optstr);
	if ((*w == '+') || (*w == '-')) {
	    action = *(w++);
	}
	else {
	    action = '\0';
	}
	if (!strcasecmp(w, "FancyIndexing")) {
	    option = FANCY_INDEXING;
	}
	else if (!strcasecmp(w, "IconsAreLinks")) {
	    option = ICONS_ARE_LINKS;
	}
	else if (!strcasecmp(w, "ScanHTMLTitles")) {
	    option = SCAN_HTML_TITLES;
	}
	else if (!strcasecmp(w, "SuppressLastModified")) {
	    option = SUPPRESS_LAST_MOD;
	}
	else if (!strcasecmp(w, "SuppressSize")) {
	    option = SUPPRESS_SIZE;
	}
	else if (!strcasecmp(w, "SuppressDescription")) {
	    option = SUPPRESS_DESC;
	}
	else if (!strcasecmp(w, "SuppressHTMLPreamble")) {
	    option = SUPPRESS_PREAMBLE;
	}
        else if (!strcasecmp(w, "SuppressColumnSorting")) {
            option = SUPPRESS_COLSORT;
	}
        else if (!strcasecmp(w, "VersionSort")) {
            option = VERSION_SORT;
	}
	else if (!strcasecmp(w, "None")) {
	    if (action != '\0') {
		return "Cannot combine '+' or '-' with 'None' keyword";
	    }
	    opts = NO_OPTIONS;
	    opts_add = 0;
	    opts_remove = 0;
	}
	else if (!strcasecmp(w, "IconWidth")) {
	    if (action != '-') {
		d_cfg->icon_width = DEFAULT_ICON_WIDTH;
	    }
	    else {
		d_cfg->icon_width = 0;
	    }
	}
	else if (!strncasecmp(w, "IconWidth=", 10)) {
	    if (action == '-') {
		return "Cannot combine '-' with IconWidth=n";
	    }
	    d_cfg->icon_width = atoi(&w[10]);
	}
	else if (!strcasecmp(w, "IconHeight")) {
	    if (action != '-') {
		d_cfg->icon_height = DEFAULT_ICON_HEIGHT;
	    }
	    else {
		d_cfg->icon_height = 0;
	    }
	}
	else if (!strncasecmp(w, "IconHeight=", 11)) {
	    if (action == '-') {
		return "Cannot combine '-' with IconHeight=n";
	    }
	    d_cfg->icon_height = atoi(&w[11]);
	}
	else if (!strcasecmp(w, "NameWidth")) {
	    if (action != '-') {
		return "NameWidth with no value may only appear as "
		       "'-NameWidth'";
	    }
	    d_cfg->name_width = DEFAULT_NAME_WIDTH;
	    d_cfg->name_adjust = K_NOADJUST;
	}
	else if (!strncasecmp(w, "NameWidth=", 10)) {
	    if (action == '-') {
		return "Cannot combine '-' with NameWidth=n";
	    }
	    if (w[10] == '*') {
		d_cfg->name_adjust = K_ADJUST;
	    }
	    else {
		int width = atoi(&w[10]);

		if (width < 5) {
		    return "NameWidth value must be greater than 5";
		}
		d_cfg->name_width = width;
		d_cfg->name_adjust = K_NOADJUST;
	    }
	}
	else {
	    return "Invalid directory indexing option";
	}
	if (action == '\0') {
	    opts |= option;
	    opts_add = 0;
	    opts_remove = 0;
	}
	else if (action == '+') {
	    opts_add |= option;
	    opts_remove &= ~option;
	}
	else {
	    opts_remove |= option;
	    opts_add &= ~option;
	}
    }
    if ((opts & NO_OPTIONS) && (opts & ~NO_OPTIONS)) {
	return "Cannot combine other IndexOptions keywords with 'None'";
    }
    d_cfg->incremented_opts = opts_add;
    d_cfg->decremented_opts = opts_remove;
    d_cfg->opts = opts;
    return NULL;
}

static const char *set_default_order(cmd_parms *cmd, void *m, const char *direction,
				     const char *key)
{
    char temp[4];
    autoindex_config_rec *d_cfg = (autoindex_config_rec *) m;

    apr_cpystrn(temp, "k=d", sizeof(temp));
    if (!strcasecmp(direction, "Ascending")) {
	temp[2] = D_ASCENDING;
    }
    else if (!strcasecmp(direction, "Descending")) {
	temp[2] = D_DESCENDING;
    }
    else {
	return "First keyword must be 'Ascending' or 'Descending'";
    }

    if (!strcasecmp(key, "Name")) {
	temp[0] = K_NAME;
    }
    else if (!strcasecmp(key, "Date")) {
	temp[0] = K_LAST_MOD;
    }
    else if (!strcasecmp(key, "Size")) {
	temp[0] = K_SIZE;
    }
    else if (!strcasecmp(key, "Description")) {
	temp[0] = K_DESC;
    }
    else {
	return "Second keyword must be 'Name', 'Date', 'Size', or "
	    "'Description'";
    }

    if (d_cfg->default_order == NULL) {
	d_cfg->default_order = apr_palloc(cmd->pool, 4);
	d_cfg->default_order[3] = '\0';
    }
    apr_cpystrn(d_cfg->default_order, temp, sizeof(temp));
    return NULL;
}

#define DIR_CMD_PERMS OR_INDEXES

static const command_rec autoindex_cmds[] =
{
    AP_INIT_ITERATE2("AddIcon", add_icon, BY_PATH, DIR_CMD_PERMS, 
                     "an icon URL followed by one or more filenames"),
    AP_INIT_ITERATE2("AddIconByType", add_icon, BY_TYPE, DIR_CMD_PERMS,
                     "an icon URL followed by one or more MIME types"),
    AP_INIT_ITERATE2("AddIconByEncoding", add_icon, BY_ENCODING, DIR_CMD_PERMS,
                     "an icon URL followed by one or more content encodings"),
    AP_INIT_ITERATE2("AddAlt", add_alt, BY_PATH, DIR_CMD_PERMS,
                     "alternate descriptive text followed by one or more filenames"),
    AP_INIT_ITERATE2("AddAltByType", add_alt, BY_TYPE, DIR_CMD_PERMS,
                     "alternate descriptive text followed by one or more MIME types"),
    AP_INIT_ITERATE2("AddAltByEncoding", add_alt, BY_ENCODING, DIR_CMD_PERMS,
                     "alternate descriptive text followed by one or more content encodings"),
    AP_INIT_RAW_ARGS("IndexOptions", add_opts, NULL, DIR_CMD_PERMS,
                     "one or more index options"),
    AP_INIT_TAKE2("IndexOrderDefault", set_default_order, NULL, DIR_CMD_PERMS,
                  "{Ascending,Descending} {Name,Size,Description,Date}"),
    AP_INIT_ITERATE("IndexIgnore", add_ignore, NULL, DIR_CMD_PERMS,
                    "one or more file extensions"),
    AP_INIT_ITERATE2("AddDescription", add_desc, BY_PATH, DIR_CMD_PERMS,
                     "Descriptive text followed by one or more filenames"),
    AP_INIT_TAKE1("HeaderName", add_header, NULL, DIR_CMD_PERMS,
                  "a filename"),
    AP_INIT_TAKE1("ReadmeName", add_readme, NULL, DIR_CMD_PERMS,
                  "a filename"),
    AP_INIT_FLAG("FancyIndexing", fancy_indexing, NULL, DIR_CMD_PERMS,
                 "Limited to 'on' or 'off' (superseded by IndexOptions FancyIndexing)"),
    AP_INIT_TAKE1("DefaultIcon", ap_set_string_slot,
                  (void *) XtOffsetOf(autoindex_config_rec, default_icon),
                  DIR_CMD_PERMS, "an icon URL"),
    {NULL}
};

static void *create_autoindex_config(apr_pool_t *p, char *dummy)
{
    autoindex_config_rec *new =
    (autoindex_config_rec *) apr_pcalloc(p, sizeof(autoindex_config_rec));

    new->icon_width = 0;
    new->icon_height = 0;
    new->name_width = DEFAULT_NAME_WIDTH;
    new->name_adjust = K_UNSET;
    new->icon_list = apr_array_make(p, 4, sizeof(struct item));
    new->alt_list = apr_array_make(p, 4, sizeof(struct item));
    new->desc_list = apr_array_make(p, 4, sizeof(ai_desc_t));
    new->ign_list = apr_array_make(p, 4, sizeof(struct item));
    new->hdr_list = apr_array_make(p, 4, sizeof(struct item));
    new->rdme_list = apr_array_make(p, 4, sizeof(struct item));
    new->opts = 0;
    new->incremented_opts = 0;
    new->decremented_opts = 0;
    new->default_order = NULL;

    return (void *) new;
}

static void *merge_autoindex_configs(apr_pool_t *p, void *basev, void *addv)
{
    autoindex_config_rec *new;
    autoindex_config_rec *base = (autoindex_config_rec *) basev;
    autoindex_config_rec *add = (autoindex_config_rec *) addv;

    new = (autoindex_config_rec *) apr_pcalloc(p, sizeof(autoindex_config_rec));
    new->default_icon = add->default_icon ? add->default_icon
                                          : base->default_icon;
    new->icon_height = add->icon_height ? add->icon_height : base->icon_height;
    new->icon_width = add->icon_width ? add->icon_width : base->icon_width;

    new->alt_list = apr_array_append(p, add->alt_list, base->alt_list);
    new->ign_list = apr_array_append(p, add->ign_list, base->ign_list);
    new->hdr_list = apr_array_append(p, add->hdr_list, base->hdr_list);
    new->desc_list = apr_array_append(p, add->desc_list, base->desc_list);
    new->icon_list = apr_array_append(p, add->icon_list, base->icon_list);
    new->rdme_list = apr_array_append(p, add->rdme_list, base->rdme_list);
    if (add->opts & NO_OPTIONS) {
	/*
	 * If the current directory says 'no options' then we also
	 * clear any incremental mods from being inheritable further down.
	 */
	new->opts = NO_OPTIONS;
	new->incremented_opts = 0;
	new->decremented_opts = 0;
    }
    else {
	/*
	 * If there were any nonincremental options selected for
	 * this directory, they dominate and we don't inherit *anything.*
	 * Contrariwise, we *do* inherit if the only settings here are
	 * incremental ones.
	 */
	if (add->opts == 0) {
	    new->incremented_opts = (base->incremented_opts 
				     | add->incremented_opts)
		                    & ~add->decremented_opts;
	    new->decremented_opts = (base->decremented_opts
				     | add->decremented_opts);
	    /*
	     * We may have incremental settings, so make sure we don't
	     * inadvertently inherit an IndexOptions None from above.
	     */
	    new->opts = (base->opts & ~NO_OPTIONS);
	}
	else {
	    /*
	     * There are local nonincremental settings, which clear
	     * all inheritance from above.  They *are* the new base settings.
	     */
	    new->opts = add->opts;;
	}
	/*
	 * We're guaranteed that there'll be no overlap between
	 * the add-options and the remove-options.
	 */
	new->opts |= new->incremented_opts;
	new->opts &= ~new->decremented_opts;
    }
    /*
     * Inherit the NameWidth settings if there aren't any specific to
     * the new location; otherwise we'll end up using the defaults set in the
     * config-rec creation routine.
     */
    if (add->name_adjust == K_UNSET) {
	new->name_width = base->name_width;
	new->name_adjust = base->name_adjust;
    }
    else {
	new->name_width = add->name_width;
	new->name_adjust = add->name_adjust;
    }

    new->default_order = (add->default_order != NULL)
	? add->default_order : base->default_order;
    return new;
}

/****************************************************************
 *
 * Looking things up in config entries...
 */

/* Structure used to hold entries when we're actually building an index */

struct ent {
    char *name;
    char *icon;
    char *alt;
    char *desc;
    off_t size;
    apr_time_t lm;
    struct ent *next;
    int ascending, version_sort;
    char key;
};

static char *find_item(request_rec *r, apr_array_header_t *list, int path_only)
{
    const char *content_type = ap_field_noparam(r->pool, r->content_type);
    const char *content_encoding = r->content_encoding;
    char *path = r->filename;

    struct item *items = (struct item *) list->elts;
    int i;

    for (i = 0; i < list->nelts; ++i) {
	struct item *p = &items[i];

	/* Special cased for ^^DIRECTORY^^ and ^^BLANKICON^^ */
	if ((path[0] == '^') || (!ap_strcmp_match(path, p->apply_path))) {
	    if (!*(p->apply_to)) {
		return p->data;
	    }
	    else if (p->type == BY_PATH || path[0] == '^') {
	        if (!ap_strcmp_match(path, p->apply_to)) {
		    return p->data;
		}
	    }
	    else if (!path_only) {
		if (!content_encoding) {
		    if (p->type == BY_TYPE) {
			if (content_type
			    && !ap_strcasecmp_match(content_type,
						    p->apply_to)) {
			    return p->data;
			}
		    }
		}
		else {
		    if (p->type == BY_ENCODING) {
			if (!ap_strcasecmp_match(content_encoding,
						 p->apply_to)) {
			    return p->data;
			}
		    }
		}
	    }
	}
    }
    return NULL;
}

#define find_icon(d,p,t) find_item(p,d->icon_list,t)
#define find_alt(d,p,t) find_item(p,d->alt_list,t)
#define find_header(d,p) find_item(p,d->hdr_list,0)
#define find_readme(d,p) find_item(p,d->rdme_list,0)

static char *find_default_icon(autoindex_config_rec *d, char *bogus_name)
{
    request_rec r;

    /* Bleah.  I tried to clean up find_item, and it lead to this bit
     * of ugliness.   Note that the fields initialized are precisely
     * those that find_item looks at...
     */

    r.filename = bogus_name;
    r.content_type = r.content_encoding = NULL;

    return find_item(&r, d->icon_list, 1);
}

/*
 * Look through the list of pattern/description pairs and return the first one
 * if any) that matches the filename in the request.  If multiple patterns
 * match, only the first one is used; since the order in the array is the
 * same as the order in which directives were processed, earlier matching
 * directives will dominate.
 */

#ifdef CASE_BLIND_FILESYSTEM
#define MATCH_FLAGS FNM_CASE_BLIND
#else
#define MATCH_FLAGS 0
#endif

static char *find_desc(autoindex_config_rec *dcfg, request_rec *r)
{
    int i;
    ai_desc_t *list = (ai_desc_t *) dcfg->desc_list->elts;
    const char *filename_full = r->filename;
    const char *filename_only;
    const char *filename;

    /*
     * If the filename includes a path, extract just the name itself
     * for the simple matches.
     */
    if ((filename_only = ap_strrchr_c(filename_full, '/')) == NULL) {
	filename_only = filename_full;
    }
    else {
	filename_only++;
    }
    for (i = 0; i < dcfg->desc_list->nelts; ++i) {
	ai_desc_t *tuple = &list[i];
	int found;

	/*
	 * Only use the full-path filename if the pattern contains '/'s.
	 */
	filename = (tuple->full_path) ? filename_full : filename_only;
	/*
	 * Make the comparison using the cheapest method; only do
	 * wildcard checking if we must.
	 */
	if (tuple->wildcards) {
	    found = (apr_fnmatch(tuple->pattern, filename, MATCH_FLAGS) == 0);
	}
	else {
	    found = (ap_strstr_c(filename, tuple->pattern) != NULL);
	}
	if (found) {
	    return tuple->description;
	}
    }
    return NULL;
}

static int ignore_entry(autoindex_config_rec *d, char *path)
{
    apr_array_header_t *list = d->ign_list;
    struct item *items = (struct item *) list->elts;
    char *tt;
    int i;

    if ((tt = strrchr(path, '/')) == NULL) {
	tt = path;
    }
    else {
	tt++;
    }

    for (i = 0; i < list->nelts; ++i) {
	struct item *p = &items[i];
	char *ap;

	if ((ap = strrchr(p->apply_to, '/')) == NULL) {
	    ap = p->apply_to;
	}
	else {
	    ap++;
	}

#ifndef CASE_BLIND_FILESYSTEM
	if (!ap_strcmp_match(path, p->apply_path)
	    && !ap_strcmp_match(tt, ap)) {
	    return 1;
	}
#else  /* !CASE_BLIND_FILESYSTEM */
	/*
	 * On some platforms, the match must be case-blind.  This is really
	 * a factor of the filesystem involved, but we can't detect that
	 * reliably - so we have to granularise at the OS level.
	 */
	if (!ap_strcasecmp_match(path, p->apply_path)
	    && !ap_strcasecmp_match(tt, ap)) {
	    return 1;
	}
#endif /* !CASE_BLIND_FILESYSTEM */
    }
    return 0;
}

/*****************************************************************
 *
 * Actually generating output
 */

/*
 * Elements of the emitted document:
 *	Preamble
 *		Emitted unless SUPPRESS_PREAMBLE is set AND ap_run_sub_req
 *		succeeds for the (content_type == text/html) header file.
 *	Header file
 *		Emitted if found (and able).
 *	H1 tag line
 *		Emitted if a header file is NOT emitted.
 *	Directory stuff
 *		Always emitted.
 *	HR
 *		Emitted if FANCY_INDEXING is set.
 *	Readme file
 *		Emitted if found (and able).
 *	ServerSig
 *		Emitted if ServerSignature is not Off AND a readme file
 *		is NOT emitted.
 *	Postamble
 *		Emitted unless SUPPRESS_PREAMBLE is set AND ap_run_sub_req
 *		succeeds for the (content_type == text/html) readme file.
 */


/*
 * emit a plain text file
 */
static void do_emit_plain(request_rec *r, apr_file_t *f)
{
    char buf[AP_IOBUFSIZE + 1];
    int i, c, ch;
    apr_size_t n;
    apr_status_t stat;

    ap_rputs("<PRE>\n", r);
    while (!apr_file_eof(f)) {
	do {
            n = sizeof(char) * AP_IOBUFSIZE;
	    stat = apr_file_read(f, buf, &n);
	}
	while (stat != APR_SUCCESS && APR_STATUS_IS_EINTR(stat));
	if (n == -1 || n == 0) {
	    break;
	}
	buf[n] = '\0';
	c = 0;
	while (c < n) {
	    for (i = c; i < n; i++) {
		if (buf[i] == '<' || buf[i] == '>' || buf[i] == '&') {
		    break;
		}
	    }
	    ch = buf[i];
	    buf[i] = '\0';
	    ap_rputs(&buf[c], r);
	    if (ch == '<') {
		ap_rputs("&lt;", r);
	    }
	    else if (ch == '>') {
		ap_rputs("&gt;", r);
	    }
	    else if (ch == '&') {
		ap_rputs("&amp;", r);
	    }
	    c = i + 1;
	}
    }
    ap_rputs("</PRE>\n", r);
}

/*
 * Handle the preamble through the H1 tag line, inclusive.  Locate
 * the file with a subrequests.  Process text/html documents by actually
 * running the subrequest; text/xxx documents get copied verbatim,
 * and any other content type is ignored.  This means that a non-text
 * document (such as HEADER.gif) might get multiviewed as the result
 * instead of a text document, meaning nothing will be displayed, but
 * oh well.
 */
static void emit_head(request_rec *r, char *header_fname, int suppress_amble,
		      char *title)
{
    apr_file_t *f = NULL;
    request_rec *rr = NULL;
    int emit_amble = 1;
    int emit_H1 = 1;

    /*
     * If there's a header file, send a subrequest to look for it.  If it's
     * found and a text file, handle it -- otherwise fall through and
     * pretend there's nothing there.
     */
    if ((header_fname != NULL)
	&& (rr = ap_sub_req_lookup_uri(header_fname, r, NULL))
	&& (rr->status == HTTP_OK)
	&& (rr->filename != NULL)
	&& rr->finfo.filetype == APR_REG) {
	/*
	 * Check for the two specific cases we allow: text/html and
	 * text/anything-else.  The former is allowed to be processed for
	 * SSIs.
	 */
	if (rr->content_type != NULL) {
	    if (!strcasecmp(ap_field_noparam(r->pool, rr->content_type),
			    "text/html")) {
		/* Hope everything will work... */
		emit_amble = 0;
		emit_H1 = 0;

		if (! suppress_amble) {
		    emit_preamble(r, title);
		}
		/*
		 * If there's a problem running the subrequest, display the
		 * preamble if we didn't do it before -- the header file
		 * didn't get displayed.
		 */
		if (ap_run_sub_req(rr) != OK) {
		    /* It didn't work */
		    emit_amble = suppress_amble;
		    emit_H1 = 1;
		}
	    }
	    else if (!strncasecmp("text/", rr->content_type, 5)) {
		/*
		 * If we can open the file, prefix it with the preamble
		 * regardless; since we'll be sending a <PRE> block around
		 * the file's contents, any HTML header it had won't end up
		 * where it belongs.
		 */
		if (apr_file_open(&f, rr->filename, APR_READ,
                            APR_OS_DEFAULT, r->pool) == APR_SUCCESS) {
		    emit_preamble(r, title);
		    emit_amble = 0;
		    do_emit_plain(r, f);
		    apr_file_close(f);
		    emit_H1 = 0;
		}
	    }
	}
    }

    if (emit_amble) {
	emit_preamble(r, title);
    }
    if (emit_H1) {
	ap_rvputs(r, "<H1>Index of ", title, "</H1>\n", NULL);
    }
    if (rr != NULL) {
	ap_destroy_sub_req(rr);
    }
}


/*
 * Handle the Readme file through the postamble, inclusive.  Locate
 * the file with a subrequests.  Process text/html documents by actually
 * running the subrequest; text/xxx documents get copied verbatim,
 * and any other content type is ignored.  This means that a non-text
 * document (such as FOOTER.gif) might get multiviewed as the result
 * instead of a text document, meaning nothing will be displayed, but
 * oh well.
 */
static void emit_tail(request_rec *r, char *readme_fname, int suppress_amble)
{
    apr_file_t *f = NULL;
    request_rec *rr = NULL;
    int suppress_post = 0;
    int suppress_sig = 0;

    /*
     * If there's a readme file, send a subrequest to look for it.  If it's
     * found and a text file, handle it -- otherwise fall through and
     * pretend there's nothing there.
     */
    if ((readme_fname != NULL)
	&& (rr = ap_sub_req_lookup_uri(readme_fname, r, NULL))
	&& (rr->status == HTTP_OK)
	&& (rr->filename != NULL)
	&& rr->finfo.filetype == APR_REG) {
	/*
	 * Check for the two specific cases we allow: text/html and
	 * text/anything-else.  The former is allowed to be processed for
	 * SSIs.
	 */
	if (rr->content_type != NULL) {
	    if (!strcasecmp(ap_field_noparam(r->pool, rr->content_type),
			    "text/html")) {
		if (ap_run_sub_req(rr) == OK) {
		    /* worked... */
		    suppress_sig = 1;
		    suppress_post = suppress_amble;
		}
	    }
	    else if (!strncasecmp("text/", rr->content_type, 5)) {
		/*
		 * If we can open the file, suppress the signature.
		 */
		if (apr_file_open(&f, rr->filename, APR_READ,
                            APR_OS_DEFAULT, r->pool) == APR_SUCCESS) {
		    do_emit_plain(r, f);
		    apr_file_close(f);
		    suppress_sig = 1;
		}
	    }
	}
    }
    
    if (!suppress_sig) {
	ap_rputs(ap_psignature("", r), r);
    }
    if (!suppress_post) {
	ap_rputs("</BODY></HTML>\n", r);
    }
    if (rr != NULL) {
	ap_destroy_sub_req(rr);
    }
}


static char *find_title(request_rec *r)
{
    char titlebuf[MAX_STRING_LEN], *find = "<TITLE>";
    apr_file_t *thefile = NULL;
    int x, y, p;
    apr_size_t n;

    if (r->status != HTTP_OK) {
	return NULL;
    }
    if ((r->content_type != NULL)
	&& (!strcasecmp(ap_field_noparam(r->pool, r->content_type),
			"text/html")
	    || !strcmp(r->content_type, INCLUDES_MAGIC_TYPE))
	&& !r->content_encoding) {
        if (apr_file_open(&thefile, r->filename, APR_READ,
                    APR_OS_DEFAULT, r->pool) != APR_SUCCESS) {
	    return NULL;
	}
        n = sizeof(char) * (MAX_STRING_LEN - 1);
	apr_file_read(thefile, titlebuf, &n);
	if (n <= 0) {
	    apr_file_close(thefile);
	    return NULL;
	}
	titlebuf[n] = '\0';
	for (x = 0, p = 0; titlebuf[x]; x++) {
	    if (apr_toupper(titlebuf[x]) == find[p]) {
		if (!find[++p]) {
		    if ((p = ap_ind(&titlebuf[++x], '<')) != -1) {
			titlebuf[x + p] = '\0';
		    }
		    /* Scan for line breaks for Tanmoy's secretary */
		    for (y = x; titlebuf[y]; y++) {
			if ((titlebuf[y] == CR) || (titlebuf[y] == LF)) {
			    if (y == x) {
				x++;
			    }
			    else {
				titlebuf[y] = ' ';
			    }
			}
		    }
		    apr_file_close(thefile);
		    return apr_pstrdup(r->pool, &titlebuf[x]);
		}
	    }
	    else {
		p = 0;
	    }
	}
	apr_file_close(thefile);
    }
    return NULL;
}

static struct ent *make_autoindex_entry(const char *name, int autoindex_opts,
					autoindex_config_rec *d,
					request_rec *r, char keyid,
					char direction)
{
    struct ent *p;

    if ((name[0] == '.') && (!name[1])) {
	return (NULL);
    }

    if (ignore_entry(d, ap_make_full_path(r->pool, r->filename, name))) {
        return (NULL);
    }

    p = (struct ent *) apr_pcalloc(r->pool, sizeof(struct ent));
    p->name = apr_pstrdup(r->pool, name);
    p->size = -1;
    p->icon = NULL;
    p->alt = NULL;
    p->desc = NULL;
    p->lm = -1;
    p->key = apr_toupper(keyid);
    p->ascending = (apr_toupper(direction) == D_ASCENDING);
    p->version_sort = autoindex_opts & VERSION_SORT;

    if (autoindex_opts & FANCY_INDEXING) {
        request_rec *rr = ap_sub_req_lookup_file(name, r, NULL);

	if (rr->finfo.filetype != 0) {
	    p->lm = rr->finfo.mtime;
	    if (rr->finfo.filetype == APR_DIR) {
	        if (!(p->icon = find_icon(d, rr, 1))) {
		    p->icon = find_default_icon(d, "^^DIRECTORY^^");
		}
		if (!(p->alt = find_alt(d, rr, 1))) {
		    p->alt = "DIR";
		}
		p->size = -1;
		p->name = apr_pstrcat(r->pool, name, "/", NULL);
	    }
	    else {
		p->icon = find_icon(d, rr, 0);
		p->alt = find_alt(d, rr, 0);
		p->size = rr->finfo.size;
	    }
	}

	p->desc = find_desc(d, rr);

	if ((!p->desc) && (autoindex_opts & SCAN_HTML_TITLES)) {
	    p->desc = apr_pstrdup(r->pool, find_title(rr));
	}

	ap_destroy_sub_req(rr);
    }
    /*
     * We don't need to take any special action for the file size key.  If
     * we did, it would go here.
     */
    if (keyid == K_LAST_MOD) {
        if (p->lm < 0) {
	    p->lm = 0;
	}
    }
    return (p);
}

static char *terminate_description(autoindex_config_rec *d, char *desc,
				   int autoindex_opts)
{
    int maxsize = 23;
    register int x;

    if (autoindex_opts & SUPPRESS_LAST_MOD) {
	maxsize += 19;
    }
    if (autoindex_opts & SUPPRESS_SIZE) {
	maxsize += 7;
    }

    for (x = 0; desc[x] && (maxsize > 0 || desc[x]=='<'); x++) {
	if (desc[x] == '<') {
	    while (desc[x] != '>') {
		if (!desc[x]) {
		    maxsize = 0;
		    break;
		}
		++x;
	    }
	}
 	else if (desc[x] == '&') {
 	    /* entities like &auml; count as one character */
 	    --maxsize;
 	    for ( ; desc[x] != ';'; ++x) {
 		if (desc[x] == '\0') {
                     maxsize = 0;
                     break;
		}
	    }
        }
	else {
	    --maxsize;
	}
    }
    if (!maxsize && desc[x] != '\0') {
	desc[x - 1] = '>';	/* Grump. */
	desc[x] = '\0';		/* Double Grump! */
    }
    return desc;
}

/*
 * Emit the anchor for the specified field.  If a field is the key for the
 * current request, the link changes its meaning to reverse the order when
 * selected again.  Non-active fields always start in ascending order.
 */
static void emit_link(request_rec *r, char *anchor, char fname, char curkey,
                      char curdirection, int nosort)
{
    char qvalue[5];
    int reverse;

    if (!nosort) {
	qvalue[0] = '?';
	qvalue[1] = fname;
	qvalue[2] = '=';
	qvalue[4] = '\0';
	reverse = ((curkey == fname) && (curdirection == D_ASCENDING));
	qvalue[3] = reverse ? D_DESCENDING : D_ASCENDING;
	ap_rvputs(r, "<A HREF=\"", qvalue, "\">", anchor, "</A>", NULL);
    }
    else {
        ap_rputs(anchor, r);
    }
}

static void output_directories(struct ent **ar, int n,
			       autoindex_config_rec *d, request_rec *r,
			       int autoindex_opts, char keyid, char direction)
{
    int x;
    apr_size_t rv;
    char *name = r->uri;
    char *tp;
    int static_columns = (autoindex_opts & SUPPRESS_COLSORT);
    apr_pool_t *scratch;
    int name_width;
    char *name_scratch;
    char *pad_scratch;

    apr_pool_create(&scratch, r->pool);
    if (name[0] == '\0') {
	name = "/";
    }

    name_width = d->name_width;
    if (d->name_adjust == K_ADJUST) {
	for (x = 0; x < n; x++) {
	    int t = strlen(ar[x]->name);
	    if (t > name_width) {
		name_width = t;
	    }
	}
    }
    name_scratch = apr_palloc(r->pool, name_width + 1);
    pad_scratch = apr_palloc(r->pool, name_width + 1);
    memset(pad_scratch, ' ', name_width);
    pad_scratch[name_width] = '\0';

    if (autoindex_opts & FANCY_INDEXING) {
	ap_rputs("<PRE>", r);
	if ((tp = find_default_icon(d, "^^BLANKICON^^"))) {
	    ap_rvputs(r, "<IMG SRC=\"", ap_escape_html(scratch, tp),
		   "\" ALT=\"     \"", NULL);
	    if (d->icon_width && d->icon_height) {
		ap_rprintf
		    (
			r,
			" HEIGHT=\"%d\" WIDTH=\"%d\"",
			d->icon_height,
			d->icon_width
		    );
	    }
	    ap_rputs("> ", r);
	}
        emit_link(r, "Name", K_NAME, keyid, direction, static_columns);
	ap_rputs(pad_scratch + 4, r);
	/*
	 * Emit the guaranteed-at-least-one-space-between-columns byte.
	 */
	ap_rputs(" ", r);
	if (!(autoindex_opts & SUPPRESS_LAST_MOD)) {
            emit_link(r, "Last modified", K_LAST_MOD, keyid, direction,
                      static_columns);
	    ap_rputs("       ", r);
	}
	if (!(autoindex_opts & SUPPRESS_SIZE)) {
            emit_link(r, "Size", K_SIZE, keyid, direction, static_columns);
	    ap_rputs("  ", r);
	}
	if (!(autoindex_opts & SUPPRESS_DESC)) {
            emit_link(r, "Description", K_DESC, keyid, direction,
                      static_columns);
	}
	ap_rputs("\n<HR>\n", r);
    }
    else {
	ap_rputs("<UL>", r);
    }

    for (x = 0; x < n; x++) {
	char *anchor, *t, *t2;
	int nwidth;

	apr_pool_clear(scratch);

	if (is_parent(ar[x]->name)) {
	    t = ap_make_full_path(scratch, name, "../");
	    ap_getparents(t);
	    if (t[0] == '\0') {
		t = "/";
	    }
	    t2 = "Parent Directory";
	    anchor = ap_escape_html(scratch, ap_os_escape_path(scratch, t, 0));
	}
	else {
	    t = ar[x]->name;
	    t2 = t;
	    anchor = ap_escape_html(scratch, ap_os_escape_path(scratch, t, 0));
	}

	if (autoindex_opts & FANCY_INDEXING) {
	    if (autoindex_opts & ICONS_ARE_LINKS) {
		ap_rvputs(r, "<A HREF=\"", anchor, "\">", NULL);
	    }
	    if ((ar[x]->icon) || d->default_icon) {
		ap_rvputs(r, "<IMG SRC=\"",
			  ap_escape_html(scratch,
					 ar[x]->icon ? ar[x]->icon
					             : d->default_icon),
			  "\" ALT=\"[", (ar[x]->alt ? ar[x]->alt : "   "),
			  "]\"", NULL);
		if (d->icon_width && d->icon_height) {
		    ap_rprintf(r, " HEIGHT=\"%d\" WIDTH=\"%d\"",
			       d->icon_height, d->icon_width);
		}
		ap_rputs(">", r);
	    }
	    if (autoindex_opts & ICONS_ARE_LINKS) {
		ap_rputs("</A>", r);
	    }

	    nwidth = strlen(t2);
	    if (nwidth > name_width) {
	      memcpy(name_scratch, t2, name_width - 3);
	      name_scratch[name_width - 3] = '.';
	      name_scratch[name_width - 2] = '.';
	      name_scratch[name_width - 1] = '>';
	      name_scratch[name_width] = 0;
	      t2 = name_scratch;
	      nwidth = name_width;
	    }
	    ap_rvputs(r, " <A HREF=\"", anchor, "\">",
	      ap_escape_html(scratch, t2), "</A>", pad_scratch + nwidth,
	      NULL);
	    /*
	     * The blank before the storm.. er, before the next field.
	     */
	    ap_rputs(" ", r);
	    if (!(autoindex_opts & SUPPRESS_LAST_MOD)) {
		if (ar[x]->lm != -1) {
		    char time_str[MAX_STRING_LEN];
		    apr_exploded_time_t ts;
                    apr_explode_localtime(&ts, ar[x]->lm);
		    apr_strftime(time_str, &rv, MAX_STRING_LEN, 
                                "%d-%b-%Y %H:%M  ", &ts);
		    ap_rputs(time_str, r);
		}
		else {
		    /*Length="22-Feb-1998 23:42  " (see 4 lines above) */
		    ap_rputs("                   ", r);
		}
	    }
	    if (!(autoindex_opts & SUPPRESS_SIZE)) {
		ap_send_size(ar[x]->size, r);
		ap_rputs("  ", r);
	    }
	    if (!(autoindex_opts & SUPPRESS_DESC)) {
		if (ar[x]->desc) {
		    ap_rputs(terminate_description(d, ar[x]->desc,
						   autoindex_opts), r);
		}
	    }
	}
	else {
	    ap_rvputs(r, "<LI><A HREF=\"", anchor, "\"> ", t2,
		      "</A>", NULL);
	}
	ap_rputc('\n', r);
    }
    if (autoindex_opts & FANCY_INDEXING) {
	ap_rputs("</PRE>", r);
    }
    else {
	ap_rputs("</UL>", r);
    }
}

/*
 * Compare two file entries according to the sort criteria.  The return
 * is essentially a signum function value.
 */

static int dsortf(struct ent **e1, struct ent **e2)
{
    struct ent *c1;
    struct ent *c2;
    int result = 0;

    /*
     * First, see if either of the entries is for the parent directory.
     * If so, that *always* sorts lower than anything else.
     */
    if (is_parent((*e1)->name)) {
        return -1;
    }
    if (is_parent((*e2)->name)) {
        return 1;
    }
    /*
     * All of our comparisons will be of the c1 entry against the c2 one,
     * so assign them appropriately to take care of the ordering.
     */
    if ((*e1)->ascending) {
        c1 = *e1;
        c2 = *e2;
    }
    else {
        c1 = *e2;
        c2 = *e1;
    }

    switch (c1->key) {
    case K_LAST_MOD:
	if (c1->lm > c2->lm) {
            return 1;
        }
        else if (c1->lm < c2->lm) {
            return -1;
        }
        break;
    case K_SIZE:
        if (c1->size > c2->size) {
            return 1;
        }
        else if (c1->size < c2->size) {
            return -1;
        }
        break;
    case K_DESC:
	if (c1->version_sort)
	    result = apr_strnatcmp(c1->desc ? c1->desc : "", c2->desc ? c2->desc : "");
	else
	    result = strcmp(c1->desc ? c1->desc : "", c2->desc ? c2->desc : "");
        if (result) {
            return result;
        }
        break;
    }
    if (c1->version_sort)
	return apr_strnatcmp(c1->name, c2->name);
    else
	return strcmp(c1->name, c2->name);
}


static int index_directory(request_rec *r,
			   autoindex_config_rec *autoindex_conf)
{
    char *title_name = ap_escape_html(r->pool, r->uri);
    char *title_endp;
    char *name = r->filename;
    apr_finfo_t dirent;
    apr_dir_t *thedir;
    apr_status_t status;
    int num_ent = 0, x;
    struct ent *head, *p;
    struct ent **ar = NULL;
    const char *qstring;
    int autoindex_opts = autoindex_conf->opts;
    char keyid;
    char direction;

    if ((status = apr_dir_open(&thedir, name, r->pool)) != APR_SUCCESS) {
	ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
		    "Can't open directory for index: %s", r->filename);
	return HTTP_FORBIDDEN;
    }

#if APR_HAS_UNICODE_FS 
    r->content_type = "text/html;charset=utf-8";
#else
    r->content_type = "text/html";
#endif
    ap_update_mtime(r, r->finfo.mtime);
    ap_set_last_modified(r);
    ap_set_etag(r);

    if (r->header_only) {
	apr_dir_close(thedir);
	return 0;
    }

    /* Spew HTML preamble */

    title_endp = title_name + strlen(title_name) - 1;

    while (title_endp > title_name && *title_endp == '/') {
	*title_endp-- = '\0';
    }

    emit_head(r, find_header(autoindex_conf, r),
	      autoindex_opts & SUPPRESS_PREAMBLE, title_name);

    /*
     * Figure out what sort of indexing (if any) we're supposed to use.
     *
     * If no QUERY_STRING was specified or column sorting has been
     * explicitly disabled, we use the default specified by the
     * IndexOrderDefault directive (if there is one); otherwise,
     * we fall back to ascending by name.
     */
    qstring = r->args;
    if ((autoindex_opts & SUPPRESS_COLSORT)
	|| ((qstring == NULL) || (*qstring == '\0'))) {
	qstring = autoindex_conf->default_order;
    }
    /*
     * If there is no specific ordering defined for this directory,
     * default to ascending by filename.
     */
    if ((qstring == NULL) || (*qstring == '\0')) {
	keyid = K_NAME;
	direction = D_ASCENDING;
    }
    else {
	keyid = *qstring;
	ap_getword(r->pool, &qstring, '=');
	if (qstring != '\0') {
	    direction = *qstring;
	}
	else {
	    direction = D_ASCENDING;
	}
    }

    /* 
     * Since we don't know how many dir. entries there are, put them into a 
     * linked list and then arrayificate them so qsort can use them. 
     */
    head = NULL;
    while (apr_dir_read(&dirent, APR_FINFO_DIRENT, thedir) == APR_SUCCESS) {
	p = make_autoindex_entry(dirent.name, autoindex_opts,
				 autoindex_conf, r, keyid, direction);
	if (p != NULL) {
	    p->next = head;
	    head = p;
	    num_ent++;
	}
    }
    if (num_ent > 0) {
	ar = (struct ent **) apr_palloc(r->pool,
				       num_ent * sizeof(struct ent *));
	p = head;
	x = 0;
	while (p) {
	    ar[x++] = p;
	    p = p->next;
	}

	qsort((void *) ar, num_ent, sizeof(struct ent *),
	      (int (*)(const void *, const void *)) dsortf);
    }
    output_directories(ar, num_ent, autoindex_conf, r, autoindex_opts, keyid,
		       direction);
    apr_dir_close(thedir);

    if (autoindex_opts & FANCY_INDEXING) {
	ap_rputs("<HR>\n", r);
    }
    emit_tail(r, find_readme(autoindex_conf, r),
	      autoindex_opts & SUPPRESS_PREAMBLE);

    return 0;
}

/* The formal handler... */

static int handle_autoindex(request_rec *r)
{
    autoindex_config_rec *d;
    int allow_opts;

    if(strcmp(r->handler,DIR_MAGIC_TYPE))
	return DECLINED;

    allow_opts = ap_allow_options(r);

    d = (autoindex_config_rec *) ap_get_module_config(r->per_dir_config,
						      &autoindex_module);

    r->allowed |= (1 << M_GET);
    if (r->method_number != M_GET) {
	return DECLINED;
    }

    /* OK, nothing easy.  Trot out the heavy artillery... */

    if (allow_opts & OPT_INDEXES) {
	/* KLUDGE --- make the sub_req lookups happen in the right directory.
	 * Fixing this in the sub_req_lookup functions themselves is difficult,
	 * and would probably break virtual includes...
	 */

	if (r->filename[strlen(r->filename) - 1] != '/') {
	    r->filename = apr_pstrcat(r->pool, r->filename, "/", NULL);
	}
	return index_directory(r, d);
    }
    else {
	ap_log_rerror(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, r,
		     "Directory index forbidden by rule: %s", r->filename);
	return HTTP_FORBIDDEN;
    }
}

static void register_hooks(apr_pool_t *p)
{
    ap_hook_handler(handle_autoindex,NULL,NULL,APR_HOOK_MIDDLE);
}

module AP_MODULE_DECLARE_DATA autoindex_module =
{
    STANDARD20_MODULE_STUFF,
    create_autoindex_config,	/* dir config creater */
    merge_autoindex_configs,	/* dir merger --- default is to override */
    NULL,			/* server config */
    NULL,			/* merge server config */
    autoindex_cmds,		/* command apr_table_t */
    register_hooks		/* register hooks */
};
