/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2000 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:
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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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 *    notice, this list of conditions and the following disclaimer in
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 *    distribution.
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 * 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.
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 * 4. The names "Apache" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
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 * 5. Products derived from this software may not be called "Apache",
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 *
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 * 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
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 * 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_actions.c: executes scripts based on MIME type or HTTP method
 *
 * by Alexei Kosut; based on mod_cgi.c, mod_mime.c and mod_includes.c,
 * adapted by rst from original NCSA code by Rob McCool
 *
 * Usage instructions:
 *
 * Action mime/type /cgi-bin/script
 * 
 * will activate /cgi-bin/script when a file of content type mime/type is 
 * requested. It sends the URL and file path of the requested document using 
 * the standard CGI PATH_INFO and PATH_TRANSLATED environment variables.
 *
 * Script PUT /cgi-bin/script
 *
 * will activate /cgi-bin/script when a request is received with the
 * HTTP method "PUT".  The available method names are defined in httpd.h.
 * If the method is GET, the script will only be activated if the requested
 * URI includes query information (stuff after a ?-mark).
 */
#include "httpd.h"
#include "http_config.h"
#include "http_request.h"
#include "http_core.h"
#include "http_protocol.h"
#include "http_main.h"
#include "http_log.h"
#include "util_script.h"
typedef struct {
    char *method;
    char *script;
} xmethod_t;
/*
 * HTTP methods are case-sensitive, so we can't use a table structure to
 * track extension method mappings -- table keys are case-INsensitive.
 */
typedef struct {
    table *action_types;       /* Added with Action... */
    char *scripted[METHODS];   /* Added with Script... */
    array_header *xmethods;    /* Added with Script -- extension methods */
} action_dir_config;
module action_module;
static void *create_action_dir_config(pool *p, char *dummy)
{
    action_dir_config *new =
        (action_dir_config *) ap_palloc(p, sizeof(action_dir_config));
    new->action_types = ap_make_table(p, 4);
    memset(new->scripted, 0, sizeof(new->scripted));
    new->xmethods = ap_make_array(p, 4, sizeof(xmethod_t));
    return new;
}
static void *merge_action_dir_configs(pool *p, void *basev, void *addv)
{
    action_dir_config *base = (action_dir_config *) basev;
    action_dir_config *add = (action_dir_config *) addv;
    action_dir_config *new = (action_dir_config *) ap_palloc(p,
                                  sizeof(action_dir_config));
    int i;
    new->action_types = ap_overlay_tables(p, add->action_types,
                                       base->action_types);
    for (i = 0; i < METHODS; ++i) {
        new->scripted[i] = add->scripted[i] ? add->scripted[i]
                                            : base->scripted[i];
    }
    new->xmethods = ap_append_arrays(p, add->xmethods, base->xmethods);
    return new;
}
static const char *add_action(cmd_parms *cmd, action_dir_config *m, char *type,
                              char *script)
{
    ap_table_setn(m->action_types, type, script);
    return NULL;
}
static const char *set_script(cmd_parms *cmd, action_dir_config *m,
                              char *method, char *script)
{
    int methnum;
    methnum = ap_method_number_of(method);
    if (methnum == M_TRACE) {
        return "TRACE not allowed for Script";
    }
    else if (methnum != M_INVALID) {
        m->scripted[methnum] = script;
    }
    else {
        /*
         * We used to return "Unknown method type for Script"
         * but now we actually handle unknown methods.
         */
        xmethod_t *xm;
        xmethod_t *list;
        int i;
        /*
         * Scan through the list; if the method already has a script
         * defined, overwrite it.  Otherwise, add it.
         */
        list = (xmethod_t *) m->xmethods->elts;
        for (i = 0; i < m->xmethods->nelts; ++i) {
            xm = &list[i];
            if (strcmp(method, xm->method) == 0) {
                xm->script = script;
                break;
            }
        }
        if (i <= m->xmethods->nelts) {
            xm = ap_push_array(m->xmethods);
            xm->method = method;
            xm->script = script;
        }
    }
    return NULL;
}
static const command_rec action_cmds[] =
{
    {"Action", add_action, NULL, OR_FILEINFO, TAKE2,
     "a media type followed by a script name"},
    {"Script", set_script, NULL, ACCESS_CONF | RSRC_CONF, TAKE2,
     "a method followed by a script name"},
    {NULL}
};
static int action_handler(request_rec *r)
{
    action_dir_config *conf = (action_dir_config *)
        ap_get_module_config(r->per_dir_config, &action_module);
    const char *t, *action = r->handler ? r->handler : 
        ap_field_noparam(r->pool, r->content_type);
    const char *script;
    int i;
    /* Set allowed stuff */
    for (i = 0; i < METHODS; ++i) {
        if (conf->scripted[i]) {
            r->allowed |= (1 << i);
        }
    }
    /* First, check for the method-handling scripts */
    if (r->method_number == M_GET) {
        if (r->args) {
            script = conf->scripted[M_GET];
        }
        else {
            script = NULL;
        }
    }
    else {
        if (r->method_number != M_INVALID) {
            script = conf->scripted[r->method_number];
        }
        else {
            int j;
            xmethod_t *xm;
            xmethod_t *list;
            script = NULL;
            list = (xmethod_t *) conf->xmethods->elts;
            for (j = 0; j < conf->xmethods->nelts; ++j) {
                xm = &list[j];
                if (strcmp(r->method, xm->method) == 0) {
                    script = xm->script;
                    break;
                }
            }
        }
    }
    /* Check for looping, which can happen if the CGI script isn't */
    if (script && r->prev && r->prev->prev) {
        return DECLINED;
    }
    /* Second, check for actions (which override the method scripts) */
    if ((t = ap_table_get(conf->action_types,
                          action ? action : ap_default_type(r)))) {
        script = t;
    }
    if (script == NULL) {
        return DECLINED;
    }
    ap_internal_redirect_handler(ap_pstrcat(r->pool, script,
                                            ap_escape_uri(r->pool,
                                                          r->uri),
                                            r->args ? "?" : NULL,
                                            r->args, NULL), r);
    return OK;
}
static const handler_rec action_handlers[] =
{
    {"*/*", action_handler},
    {NULL}
};
module action_module =
{
    STANDARD_MODULE_STUFF,
    NULL,                       /* initializer */
    create_action_dir_config,   /* dir config creater */
    merge_action_dir_configs,   /* dir merger --- default is to override */
    NULL,                       /* server config */
    NULL,                       /* merge server config */
    action_cmds,                /* command table */
    action_handlers,            /* handlers */
    NULL,                       /* filename translation */
    NULL,                       /* check_user_id */
    NULL,                       /* check auth */
    NULL,                       /* check access */
    NULL,                       /* type_checker */
    NULL,                       /* fixups */
    NULL,                       /* logger */
    NULL,                       /* header parser */
    NULL,                       /* child_init */
    NULL,                       /* child_exit */
    NULL                        /* post read-request */
};