modules/experimental/cache_util.c

/* ====================================================================
 * The Apache Software License, Version 1.1
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 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
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 *    distribution.
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 *    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.
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 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
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 * <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.
 */

#define CORE_PRIVATE

#include "mod_cache.h"



/* -------------------------------------------------------------- */

/* return true if the request is conditional */
int ap_cache_request_is_conditional(request_rec *r)
{
    if (apr_table_get(r->headers_in, "If-Match") ||
        apr_table_get(r->headers_in, "If-None-Match") ||
        apr_table_get(r->headers_in, "If-Modified-Since") ||
        apr_table_get(r->headers_in, "If-Unmodified-Since")) {

	return 1;
    }
    return 0;
}


/* remove other filters from filter stack */
void ap_cache_reset_output_filters(request_rec *r)
{
    ap_filter_t *f = r->output_filters;

    while (f) {
        if (!strcasecmp(f->frec->name, "CORE") ||
            !strcasecmp(f->frec->name, "CONTENT_LENGTH") ||
            !strcasecmp(f->frec->name, "HTTP_HEADER")) {
            f = f->next;
            continue;
        }
        else {
            ap_remove_output_filter(f);
            f = f->next;
        }
    }
}

const char *ap_cache_get_cachetype(request_rec *r, cache_server_conf *conf, const char *url)
{
    const char *type = NULL;
    int i;

    /* loop through all the cacheenable entries */
    for (i = 0; i < conf->cacheenable->nelts; i++) {
	struct cache_enable *ent = (struct cache_enable *) conf->cacheenable->elts;
	const char *thisurl = ent[i].url;
	const char *thistype = ent[i].type;
	if ((thisurl) && !strncasecmp(thisurl, url, strlen(thisurl))) {
	    if (!type) {
		type = thistype;
	    }
	    else {
		type = apr_pstrcat(r->pool, type, ",", thistype, NULL);
	    }
	}
    }

    /* then loop through all the cachedisable entries */
    for (i = 0; i < conf->cachedisable->nelts; i++) {
	struct cache_disable *ent = (struct cache_disable *) conf->cachedisable->elts;
	const char *thisurl = ent[i].url;
	if ((thisurl) && !strncasecmp(thisurl, url, strlen(thisurl))) {
	    type = NULL;
	}
    }

    return type;
}

/*
 * list is a comma-separated list of case-insensitive tokens, with
 * optional whitespace around the tokens.
 * The return returns 1 if the token val is found in the list, or 0
 * otherwise.
 */
int ap_cache_liststr(const char *list, const char *key, char **val)
{
    int len, i;
    char *p;
    char valbuf[HUGE_STRING_LEN];
    valbuf[sizeof(valbuf)-1] = 0; /* safety terminating zero */

    len = strlen(key);

    while (list != NULL) {
	p = strchr((char *) list, ',');
	if (p != NULL) {
	    i = p - list;
	    do
		p++;
	    while (ap_isspace(*p));
	}
	else
	    i = strlen(list);

	while (i > 0 && ap_isspace(list[i - 1]))
	    i--;
	if (i == len && strncasecmp(list, key, len) == 0) {
	    if (val) {
		p = strchr((char *) list, ',');
		while (ap_isspace(*list)) {
		    list++;
		}
		if ('=' == list[0])
		    list++;
		while (ap_isspace(*list)) {
		    list++;
		}
		strncpy(valbuf, list, MIN(p-list, sizeof(valbuf)-1));
		*val = valbuf;
	    }
	    return 1;
	}
	list = p;
    }
    return 0;
}

/* return each comma separated token, one at a time */
const char *ap_cache_tokstr(apr_pool_t *p, const char *list, const char **str)
{
    apr_off_t len, i;
    const char *s;

    s = ap_strchr_c(list, ',');
    if (s != NULL) {
	i = s - list;
	do
	    s++;
	while (apr_isspace(*s));
    }
    else
	i = strlen(list);

    while (i > 0 && apr_isspace(list[i - 1]))
	i--;

    *str = s;
    if (len)
	return apr_pstrndup(p, list, len);
    else
	return NULL;

}