/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) 2007 Manlio Perillo (manlio.perillo@gmail.com)
 * Copyright (C) 2010-2013 Phusion
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS 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 AUTHOR OR 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.
 */

#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>

#include <sys/types.h>
#include <pwd.h>

#include "ngx_http_passenger_module.h"
#include "Configuration.h"
#include "ContentHandler.h"
#include "common/Constants.h"
#include "common/agents/LoggingAgent/FilterSupport.h"


static ngx_str_t headers_to_hide[] = {
    /* NOTE: Do not hide the "Status" header; some broken HTTP clients
     * expect this header. http://code.google.com/p/phusion-passenger/issues/detail?id=177
     */
    ngx_string("X-Accel-Expires"),
    ngx_string("X-Accel-Redirect"),
    ngx_string("X-Accel-Limit-Rate"),
    ngx_string("X-Accel-Buffering"),
    ngx_null_string
};

passenger_main_conf_t passenger_main_conf;

static ngx_path_init_t  ngx_http_proxy_temp_path = {
    ngx_string(NGX_HTTP_PROXY_TEMP_PATH), { 1, 2, 0 }
};


void *
passenger_create_main_conf(ngx_conf_t *cf)
{
    passenger_main_conf_t *conf;
    
    conf = ngx_pcalloc(cf->pool, sizeof(passenger_main_conf_t));
    if (conf == NULL) {
        return NGX_CONF_ERROR;
    }
    
    conf->ctl = ngx_array_create(cf->pool, 1, sizeof(ngx_keyval_t));
    if (conf->ctl == NULL) {
        return NGX_CONF_ERROR;
    }
    conf->default_ruby.data = NULL;
    conf->default_ruby.len = 0;
    conf->log_level = (ngx_int_t) NGX_CONF_UNSET;
    conf->debug_log_file.data = NULL;
    conf->debug_log_file.len = 0;
    conf->abort_on_startup_error = NGX_CONF_UNSET;
    conf->max_pool_size = (ngx_uint_t) NGX_CONF_UNSET;
    conf->pool_idle_time = (ngx_uint_t) NGX_CONF_UNSET;
    conf->user_switching = NGX_CONF_UNSET;
    conf->default_user.data = NULL;
    conf->default_user.len  = 0;
    conf->default_group.data = NULL;
    conf->default_group.len  = 0;
    conf->analytics_log_user.data = NULL;
    conf->analytics_log_user.len  = 0;
    conf->analytics_log_group.data = NULL;
    conf->analytics_log_group.len  = 0;
    conf->union_station_gateway_address.data = NULL;
    conf->union_station_gateway_address.len = 0;
    conf->union_station_gateway_port = (ngx_uint_t) NGX_CONF_UNSET;
    conf->union_station_gateway_cert.data = NULL;
    conf->union_station_gateway_cert.len = 0;
    conf->union_station_proxy_address.data = NULL;
    conf->union_station_proxy_address.len = 0;
    
    conf->prestart_uris = ngx_array_create(cf->pool, 1, sizeof(ngx_str_t));
    if (conf->prestart_uris == NULL) {
        return NGX_CONF_ERROR;
    }
    
    return conf;
}

char *
passenger_init_main_conf(ngx_conf_t *cf, void *conf_pointer)
{
    passenger_main_conf_t *conf;
    struct passwd         *user_entry;
    struct group          *group_entry;
    char buf[128];
    
    conf = &passenger_main_conf;
    *conf = *((passenger_main_conf_t *) conf_pointer);
    
    if (conf->default_ruby.len == 0) {
        conf->default_ruby.data = (u_char *) DEFAULT_RUBY;
        conf->default_ruby.len = strlen(DEFAULT_RUBY);
    }

    if (conf->log_level == (ngx_int_t) NGX_CONF_UNSET) {
        conf->log_level = DEFAULT_LOG_LEVEL;
    }
    
    if (conf->debug_log_file.len == 0) {
        conf->debug_log_file.data = (u_char *) "";
    }
    
    if (conf->abort_on_startup_error == NGX_CONF_UNSET) {
        conf->abort_on_startup_error = 0;
    }
    
    if (conf->max_pool_size == (ngx_uint_t) NGX_CONF_UNSET) {
        conf->max_pool_size = DEFAULT_MAX_POOL_SIZE;
    }
    
    if (conf->pool_idle_time == (ngx_uint_t) NGX_CONF_UNSET) {
        conf->pool_idle_time = DEFAULT_POOL_IDLE_TIME;
    }
    
    if (conf->user_switching == NGX_CONF_UNSET) {
        conf->user_switching = 1;
    }
    
    if (conf->default_user.len == 0) {
        conf->default_user.len  = sizeof(DEFAULT_WEB_APP_USER) - 1;
        conf->default_user.data = (u_char *) DEFAULT_WEB_APP_USER;
    }
    if (conf->default_user.len > sizeof(buf) - 1) {
        return "Value for 'default_user' is too long.";
    }
    memcpy(buf, conf->default_user.data, conf->default_user.len);
    buf[conf->default_user.len] = '\0';
    user_entry = getpwnam(buf);
    if (user_entry == NULL) {
        return "The user specified by the 'default_user' option does not exist.";
    }
    
    if (conf->default_group.len > 0) {
        if (conf->default_group.len > sizeof(buf) - 1) {
            return "Value for 'default_group' is too long.";
        }
        memcpy(buf, conf->default_group.data, conf->default_group.len);
        buf[conf->default_group.len] = '\0';
        group_entry = getgrnam(buf);
        if (group_entry == NULL) {
            return "The group specified by the 'default_group' option does not exist.";
        }
    }
    
    if (conf->analytics_log_user.len == 0) {
        conf->analytics_log_user.len  = sizeof(DEFAULT_ANALYTICS_LOG_USER) - 1;
        conf->analytics_log_user.data = (u_char *) DEFAULT_ANALYTICS_LOG_USER;
    }
    
    if (conf->analytics_log_group.len == 0) {
        conf->analytics_log_group.len  = sizeof(DEFAULT_ANALYTICS_LOG_GROUP) - 1;
        conf->analytics_log_group.data = (u_char *) DEFAULT_ANALYTICS_LOG_GROUP;
    }
    
    if (conf->union_station_gateway_address.len == 0) {
        conf->union_station_gateway_address.len = sizeof(DEFAULT_UNION_STATION_GATEWAY_ADDRESS) - 1;
        conf->union_station_gateway_address.data = (u_char *) DEFAULT_UNION_STATION_GATEWAY_ADDRESS;
    }
    
    if (conf->union_station_gateway_port == (ngx_uint_t) NGX_CONF_UNSET) {
        conf->union_station_gateway_port = DEFAULT_UNION_STATION_GATEWAY_PORT;
    }
    
    if (conf->union_station_gateway_cert.len == 0) {
        conf->union_station_gateway_cert.data = (u_char *) "";
    }
    
    if (conf->union_station_proxy_address.len == 0) {
        conf->union_station_proxy_address.data = (u_char *) "";
    }
    
    return NGX_CONF_OK;
}

void *
passenger_create_loc_conf(ngx_conf_t *cf)
{
    passenger_loc_conf_t  *conf;
    ngx_keyval_t          *kv;

    conf = ngx_pcalloc(cf->pool, sizeof(passenger_loc_conf_t));
    if (conf == NULL) {
        return NGX_CONF_ERROR;
    }

    /*
     * set by ngx_pcalloc():
     *
     *     conf->upstream_config.bufs.num = 0;
     *     conf->upstream_config.next_upstream = 0;
     *     conf->upstream_config.temp_path = NULL;
     *     conf->upstream_config.hide_headers_hash = { NULL, 0 };
     *     conf->upstream_config.hide_headers = NULL;
     *     conf->upstream_config.pass_headers = NULL;
     *     conf->upstream_config.uri = { 0, NULL };
     *     conf->upstream_config.location = NULL;
     *     conf->upstream_config.store_lengths = NULL;
     *     conf->upstream_config.store_values = NULL;
     */

    #include "CreateLocationConfig.c"

    /******************************/
    /******************************/

    conf->upstream_config.pass_headers = NGX_CONF_UNSET_PTR;
    conf->upstream_config.hide_headers = NGX_CONF_UNSET_PTR;

    conf->upstream_config.store = NGX_CONF_UNSET;
    conf->upstream_config.store_access = NGX_CONF_UNSET_UINT;
    conf->upstream_config.buffering = NGX_CONF_UNSET;
    conf->upstream_config.ignore_client_abort = NGX_CONF_UNSET;

    conf->upstream_config.local = NGX_CONF_UNSET_PTR;

    conf->upstream_config.connect_timeout = NGX_CONF_UNSET_MSEC;
    conf->upstream_config.send_timeout = NGX_CONF_UNSET_MSEC;
    conf->upstream_config.read_timeout = NGX_CONF_UNSET_MSEC;

    conf->upstream_config.send_lowat = NGX_CONF_UNSET_SIZE;
    conf->upstream_config.buffer_size = NGX_CONF_UNSET_SIZE;

    conf->upstream_config.busy_buffers_size_conf = NGX_CONF_UNSET_SIZE;
    conf->upstream_config.max_temp_file_size_conf = NGX_CONF_UNSET_SIZE;
    conf->upstream_config.temp_file_write_size_conf = NGX_CONF_UNSET_SIZE;

    conf->upstream_config.pass_request_headers = NGX_CONF_UNSET;
    conf->upstream_config.pass_request_body = NGX_CONF_UNSET;

#if (NGX_HTTP_CACHE)
    #if NGINX_VERSION_NUM >= 1007009
        conf->upstream_config.cache = NGX_CONF_UNSET_PTR;
    #else
        conf->upstream_config.cache = NGX_CONF_UNSET;
    #endif
    conf->upstream_config.cache_min_uses = NGX_CONF_UNSET_UINT;
    conf->upstream_config.cache_bypass = NGX_CONF_UNSET_PTR;
    conf->upstream_config.no_cache = NGX_CONF_UNSET_PTR;
    conf->upstream_config.cache_valid = NGX_CONF_UNSET_PTR;
    conf->upstream_config.cache_lock = NGX_CONF_UNSET;
    conf->upstream_config.cache_lock_timeout = NGX_CONF_UNSET_MSEC;
    #if NGINX_VERSION_NUM >= 1007008
        conf->upstream_config.cache_lock_age = NGX_CONF_UNSET_MSEC;
    #endif
#endif

    conf->upstream_config.intercept_errors = NGX_CONF_UNSET;

    conf->upstream_config.cyclic_temp_file = 0;
    conf->upstream_config.change_buffering = 1;
    
    #define DEFINE_VAR_TO_PASS(header_name, var_name) \
        kv = ngx_array_push(conf->vars_source);       \
        kv->key.data = (u_char *) header_name;        \
        kv->key.len  = strlen(header_name) + 1;       \
        kv->value.data = (u_char *) var_name;         \
        kv->value.len  = strlen(var_name) + 1
    
    conf->vars_source = ngx_array_create(cf->pool, 4, sizeof(ngx_keyval_t));
    if (conf->vars_source == NULL) {
        return NGX_CONF_ERROR;
    }
    
    DEFINE_VAR_TO_PASS("SCGI",            "1");
    DEFINE_VAR_TO_PASS("QUERY_STRING",    "$query_string");
    DEFINE_VAR_TO_PASS("REQUEST_METHOD",  "$request_method");
    DEFINE_VAR_TO_PASS("SERVER_PROTOCOL", "$server_protocol");
    DEFINE_VAR_TO_PASS("SERVER_SOFTWARE", "nginx/$nginx_version");
    DEFINE_VAR_TO_PASS("REMOTE_ADDR",     "$remote_addr");
    DEFINE_VAR_TO_PASS("REMOTE_PORT",     "$remote_port");
    DEFINE_VAR_TO_PASS("SERVER_ADDR",     "$server_addr");
    DEFINE_VAR_TO_PASS("SERVER_PORT",     "$server_port");

    ngx_str_set(&conf->upstream_config.module, "passenger");

    return conf;
}

static void
cache_loc_conf_options(ngx_conf_t *cf, passenger_loc_conf_t *conf)
{
    #include "CacheLocationConfig.c"
}

char *
passenger_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
{
    passenger_loc_conf_t         *prev = parent;
    passenger_loc_conf_t         *conf = child;

    u_char                       *p;
    size_t                        size;
    uintptr_t                    *code;
    ngx_uint_t                    i;
    ngx_str_t                    *prev_base_uris, *base_uri;
    ngx_str_t                    *prev_union_station_filters, *union_station_filter;
    ngx_keyval_t                 *src;
    ngx_hash_init_t               hash;
    ngx_http_script_compile_t     sc;
    ngx_http_script_copy_code_t  *copy;

    #include "MergeLocationConfig.c"
    if (prev->options_cache.data == NULL) {
        cache_loc_conf_options(cf, prev);
    }
    cache_loc_conf_options(cf, conf);
    
    if (prev->base_uris != NGX_CONF_UNSET_PTR) {
        if (conf->base_uris == NGX_CONF_UNSET_PTR) {
            conf->base_uris = ngx_array_create(cf->pool, 4, sizeof(ngx_str_t));
            if (conf->base_uris == NULL) {
                return NGX_CONF_ERROR;
            }
        }
        
        prev_base_uris = (ngx_str_t *) prev->base_uris->elts;
        for (i = 0; i < prev->base_uris->nelts; i++) {
            base_uri = (ngx_str_t *) ngx_array_push(conf->base_uris);
            if (base_uri == NULL) {
                return NGX_CONF_ERROR;
            }
            *base_uri = prev_base_uris[i];
        }
    }
    
    if (prev->union_station_filters != NGX_CONF_UNSET_PTR) {
        if (conf->union_station_filters == NGX_CONF_UNSET_PTR) {
            conf->union_station_filters = ngx_array_create(cf->pool, 4, sizeof(ngx_str_t));
            if (conf->union_station_filters == NULL) {
                return NGX_CONF_ERROR;
            }
        }
        
        prev_union_station_filters = (ngx_str_t *) prev->union_station_filters->elts;
        for (i = 0; i < prev->union_station_filters->nelts; i++) {
            union_station_filter = (ngx_str_t *) ngx_array_push(conf->union_station_filters);
            if (union_station_filter == NULL) {
                return NGX_CONF_ERROR;
            }
            *union_station_filter = prev_union_station_filters[i];
        }
    }

    /******************************/
    /******************************/

    #if (NGX_HTTP_CACHE) && NGINX_VERSION_NUM >= 1007009
        if (conf->upstream_config.store > 0) {
            conf->upstream_config.cache = 0;
        }
        if (conf->upstream_config.cache > 0) {
            conf->upstream_config.store = 0;
        }
    #endif

    #if NGINX_VERSION_NUM >= 1007009
        if (conf->upstream_config.store == NGX_CONF_UNSET) {
            ngx_conf_merge_value(conf->upstream_config.store,
                                      prev->upstream_config.store, 0);

            conf->upstream_config.store_lengths = prev->upstream_config.store_lengths;
            conf->upstream_config.store_values = prev->upstream_config.store_values;
        }
    #else
        if (conf->upstream_config.store != 0) {
            ngx_conf_merge_value(conf->upstream_config.store,
                                      prev->upstream_config.store, 0);

            if (conf->upstream_config.store_lengths == NULL) {
                conf->upstream_config.store_lengths = prev->upstream_config.store_lengths;
                conf->upstream_config.store_values = prev->upstream_config.store_values;
            }
        }
    #endif

    ngx_conf_merge_uint_value(conf->upstream_config.store_access,
                              prev->upstream_config.store_access, 0600);

    ngx_conf_merge_value(conf->upstream_config.buffering,
                         prev->upstream_config.buffering, 0);

    ngx_conf_merge_value(conf->upstream_config.ignore_client_abort,
                         prev->upstream_config.ignore_client_abort, 0);

    ngx_conf_merge_ptr_value(conf->upstream_config.local,
                             prev->upstream_config.local, NULL);

    ngx_conf_merge_msec_value(conf->upstream_config.connect_timeout,
                              prev->upstream_config.connect_timeout, 12000000);

    ngx_conf_merge_msec_value(conf->upstream_config.send_timeout,
                              prev->upstream_config.send_timeout, 12000000);

    ngx_conf_merge_msec_value(conf->upstream_config.read_timeout,
                              prev->upstream_config.read_timeout, 12000000);

    ngx_conf_merge_size_value(conf->upstream_config.send_lowat,
                              prev->upstream_config.send_lowat, 0);

    ngx_conf_merge_size_value(conf->upstream_config.buffer_size,
                              prev->upstream_config.buffer_size,
                              16 * 1024);


    ngx_conf_merge_bufs_value(conf->upstream_config.bufs, prev->upstream_config.bufs,
                              8, 16 * 1024);

    if (conf->upstream_config.bufs.num < 2) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "there must be at least 2 \"passenger_buffers\"");
        return NGX_CONF_ERROR;
    }


    size = conf->upstream_config.buffer_size;
    if (size < conf->upstream_config.bufs.size) {
        size = conf->upstream_config.bufs.size;
    }


    ngx_conf_merge_size_value(conf->upstream_config.busy_buffers_size_conf,
                              prev->upstream_config.busy_buffers_size_conf,
                              NGX_CONF_UNSET_SIZE);

    if (conf->upstream_config.busy_buffers_size_conf == NGX_CONF_UNSET_SIZE) {
        conf->upstream_config.busy_buffers_size = 2 * size;
    } else {
        conf->upstream_config.busy_buffers_size =
                                         conf->upstream_config.busy_buffers_size_conf;
    }

    if (conf->upstream_config.busy_buffers_size < size) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
             "\"passenger_busy_buffers_size\" must be equal to or greater "
             "than the maximum of the value of \"passenger_buffer_size\" and "
             "one of the \"passenger_buffers\"");

        return NGX_CONF_ERROR;
    }

    if (conf->upstream_config.busy_buffers_size
        > (conf->upstream_config.bufs.num - 1) * conf->upstream_config.bufs.size)
    {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
             "\"passenger_busy_buffers_size\" must be less than "
             "the size of all \"passenger_buffers\" minus one buffer");

        return NGX_CONF_ERROR;
    }


    ngx_conf_merge_size_value(conf->upstream_config.temp_file_write_size_conf,
                              prev->upstream_config.temp_file_write_size_conf,
                              NGX_CONF_UNSET_SIZE);

    if (conf->upstream_config.temp_file_write_size_conf == NGX_CONF_UNSET_SIZE) {
        conf->upstream_config.temp_file_write_size = 2 * size;
    } else {
        conf->upstream_config.temp_file_write_size =
                                      conf->upstream_config.temp_file_write_size_conf;
    }

    if (conf->upstream_config.temp_file_write_size < size) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
             "\"passenger_temp_file_write_size\" must be equal to or greater than "
             "the maximum of the value of \"passenger_buffer_size\" and "
             "one of the \"passenger_buffers\"");

        return NGX_CONF_ERROR;
    }


    ngx_conf_merge_size_value(conf->upstream_config.max_temp_file_size_conf,
                              prev->upstream_config.max_temp_file_size_conf,
                              NGX_CONF_UNSET_SIZE);

    if (conf->upstream_config.max_temp_file_size_conf == NGX_CONF_UNSET_SIZE) {
        conf->upstream_config.max_temp_file_size = 1024 * 1024 * 1024;
    } else {
        conf->upstream_config.max_temp_file_size =
                                        conf->upstream_config.max_temp_file_size_conf;
    }

    if (conf->upstream_config.max_temp_file_size != 0
        && conf->upstream_config.max_temp_file_size < size)
    {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
             "\"passenger_max_temp_file_size\" must be equal to zero to disable "
             "temporary files usage or must be equal to or greater than "
             "the maximum of the value of \"passenger_buffer_size\" and "
             "one of the \"passenger_buffers\"");

        return NGX_CONF_ERROR;
    }

    ngx_conf_merge_bitmask_value(conf->upstream_config.ignore_headers,
                                 prev->upstream_config.ignore_headers,
                                 NGX_CONF_BITMASK_SET);

    ngx_conf_merge_bitmask_value(conf->upstream_config.next_upstream,
                              prev->upstream_config.next_upstream,
                              (NGX_CONF_BITMASK_SET
                               |NGX_HTTP_UPSTREAM_FT_ERROR
                               |NGX_HTTP_UPSTREAM_FT_TIMEOUT));

    if (conf->upstream_config.next_upstream & NGX_HTTP_UPSTREAM_FT_OFF) {
        conf->upstream_config.next_upstream = NGX_CONF_BITMASK_SET
                                       |NGX_HTTP_UPSTREAM_FT_OFF;
    }

    ngx_conf_merge_path_value(cf,
                              &conf->upstream_config.temp_path,
                              prev->upstream_config.temp_path,
                              &ngx_http_proxy_temp_path);

#if (NGX_HTTP_CACHE)

    #if NGINX_VERSION_NUM >= 1007009
        if (conf->upstream_config.cache == NGX_CONF_UNSET) {
           ngx_conf_merge_value(conf->upstream_config.cache,
                                prev->upstream_config.cache, 0);

           conf->upstream_config.cache_zone = prev->upstream_config.cache_zone;
           conf->upstream_config.cache_value = prev->upstream_config.cache_value;
        }

        if (conf->upstream_config.cache_zone && conf->upstream_config.cache_zone->data == NULL) {
            ngx_shm_zone_t  *shm_zone;

            shm_zone = conf->upstream_config.cache_zone;

            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "\"scgi_cache\" zone \"%V\" is unknown",
                               &shm_zone->shm.name);

            return NGX_CONF_ERROR;
        }
    #else
        ngx_conf_merge_ptr_value(conf->upstream_config.cache,
                                 prev->upstream_config.cache, NULL);

        if (conf->upstream_config.cache && conf->upstream_config.cache->data == NULL) {
            ngx_shm_zone_t  *shm_zone;

            shm_zone = conf->upstream_config.cache;

            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "\"scgi_cache\" zone \"%V\" is unknown",
                               &shm_zone->shm.name);

            return NGX_CONF_ERROR;
        }
    #endif

    #if NGINX_VERSION_NUM >= 1007008
        ngx_conf_merge_msec_value(conf->upstream_config.cache_lock_age,
                                  prev->upstream_config.cache_lock_age, 5000);
    #endif

    ngx_conf_merge_uint_value(conf->upstream_config.cache_min_uses,
                              prev->upstream_config.cache_min_uses, 1);

    ngx_conf_merge_bitmask_value(conf->upstream_config.cache_use_stale,
                              prev->upstream_config.cache_use_stale,
                              (NGX_CONF_BITMASK_SET
                               | NGX_HTTP_UPSTREAM_FT_OFF));

    if (conf->upstream_config.cache_use_stale & NGX_HTTP_UPSTREAM_FT_OFF) {
        conf->upstream_config.cache_use_stale = NGX_CONF_BITMASK_SET
                                                | NGX_HTTP_UPSTREAM_FT_OFF;
    }

    if (conf->upstream_config.cache_use_stale & NGX_HTTP_UPSTREAM_FT_ERROR) {
        conf->upstream_config.cache_use_stale |= NGX_HTTP_UPSTREAM_FT_NOLIVE;
    }

    if (conf->upstream_config.cache_methods == 0) {
        conf->upstream_config.cache_methods = prev->upstream_config.cache_methods;
    }

    conf->upstream_config.cache_methods |= NGX_HTTP_GET | NGX_HTTP_HEAD;

    ngx_conf_merge_ptr_value(conf->upstream_config.cache_bypass,
                             prev->upstream_config.cache_bypass, NULL);

    ngx_conf_merge_ptr_value(conf->upstream_config.no_cache,
                             prev->upstream_config.no_cache, NULL);

    ngx_conf_merge_ptr_value(conf->upstream_config.cache_valid,
                             prev->upstream_config.cache_valid, NULL);

    if (conf->cache_key.value.data == NULL) {
        conf->cache_key = prev->cache_key;
    }

    ngx_conf_merge_value(conf->upstream_config.cache_lock,
                         prev->upstream_config.cache_lock, 0);

    ngx_conf_merge_msec_value(conf->upstream_config.cache_lock_timeout,
                              prev->upstream_config.cache_lock_timeout, 5000);

#endif

    ngx_conf_merge_value(conf->upstream_config.pass_request_headers,
                         prev->upstream_config.pass_request_headers, 1);
    ngx_conf_merge_value(conf->upstream_config.pass_request_body,
                         prev->upstream_config.pass_request_body, 1);

    ngx_conf_merge_value(conf->upstream_config.intercept_errors,
                         prev->upstream_config.intercept_errors, 0);


    hash.max_size = 512;
    hash.bucket_size = ngx_align(64, ngx_cacheline_size);
    hash.name = "passenger_hide_headers_hash";

    if (ngx_http_upstream_hide_headers_hash(cf, &conf->upstream_config,
            &prev->upstream_config, headers_to_hide, &hash)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (conf->upstream_config.upstream == NULL) {
        conf->upstream_config.upstream = prev->upstream_config.upstream;
    }

    if (conf->vars_source == NULL) {
        conf->flushes = prev->flushes;
        conf->vars_len = prev->vars_len;
        conf->vars = prev->vars;
        conf->vars_source = prev->vars_source;

        if (conf->vars_source == NULL) {
            return NGX_CONF_OK;
        }
    }

    conf->vars_len = ngx_array_create(cf->pool, 64, 1);
    if (conf->vars_len == NULL) {
        return NGX_CONF_ERROR;
    }

    conf->vars = ngx_array_create(cf->pool, 512, 1);
    if (conf->vars == NULL) {
        return NGX_CONF_ERROR;
    }

    src = conf->vars_source->elts;
    for (i = 0; i < conf->vars_source->nelts; i++) {

        if (ngx_http_script_variables_count(&src[i].value) == 0) {
            copy = ngx_array_push_n(conf->vars_len,
                                    sizeof(ngx_http_script_copy_code_t));
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = (ngx_http_script_code_pt)
                                                  ngx_http_script_copy_len_code;
            copy->len = src[i].key.len;


            copy = ngx_array_push_n(conf->vars_len,
                                    sizeof(ngx_http_script_copy_code_t));
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = (ngx_http_script_code_pt)
                                                 ngx_http_script_copy_len_code;
            copy->len = src[i].value.len;


            size = (sizeof(ngx_http_script_copy_code_t)
                       + src[i].key.len + src[i].value.len
                       + sizeof(uintptr_t) - 1)
                    & ~(sizeof(uintptr_t) - 1);

            copy = ngx_array_push_n(conf->vars, size);
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = ngx_http_script_copy_code;
            copy->len = src[i].key.len + src[i].value.len;

            p = (u_char *) copy + sizeof(ngx_http_script_copy_code_t);

            p = ngx_cpymem(p, src[i].key.data, src[i].key.len);
            ngx_memcpy(p, src[i].value.data, src[i].value.len);

        } else {
            copy = ngx_array_push_n(conf->vars_len,
                                    sizeof(ngx_http_script_copy_code_t));
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = (ngx_http_script_code_pt)
                                                 ngx_http_script_copy_len_code;
            copy->len = src[i].key.len;


            size = (sizeof(ngx_http_script_copy_code_t)
                    + src[i].key.len + sizeof(uintptr_t) - 1)
                    & ~(sizeof(uintptr_t) - 1);

            copy = ngx_array_push_n(conf->vars, size);
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = ngx_http_script_copy_code;
            copy->len = src[i].key.len;

            p = (u_char *) copy + sizeof(ngx_http_script_copy_code_t);
            ngx_memcpy(p, src[i].key.data, src[i].key.len);


            ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));

            sc.cf = cf;
            sc.source = &src[i].value;
            sc.flushes = &conf->flushes;
            sc.lengths = &conf->vars_len;
            sc.values = &conf->vars;

            if (ngx_http_script_compile(&sc) != NGX_OK) {
                return NGX_CONF_ERROR;
            }
        }

        code = ngx_array_push_n(conf->vars_len, sizeof(uintptr_t));
        if (code == NULL) {
            return NGX_CONF_ERROR;
        }

        *code = (uintptr_t) NULL;


        code = ngx_array_push_n(conf->vars, sizeof(uintptr_t));
        if (code == NULL) {
            return NGX_CONF_ERROR;
        }

        *code = (uintptr_t) NULL;
    }

    code = ngx_array_push_n(conf->vars_len, sizeof(uintptr_t));
    if (code == NULL) {
        return NGX_CONF_ERROR;
    }

    *code = (uintptr_t) NULL;

    return NGX_CONF_OK;
}

#ifndef PASSENGER_IS_ENTERPRISE
static char *
passenger_enterprise_only(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) {
    return ": this feature is only available in Phusion Passenger Enterprise. "
        "You are currently running the open source Phusion Passenger Enterprise. "
        "Please learn more about and/or buy Phusion Passenger Enterprise at https://www.phusionpassenger.com/enterprise ;";
}
#endif

static char *
passenger_enabled(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    passenger_loc_conf_t        *passenger_conf = conf;
    ngx_http_core_loc_conf_t    *clcf;
    ngx_str_t                   *value;
    ngx_url_t                    upstream_url;

    value = cf->args->elts;
    if (ngx_strcasecmp(value[1].data, (u_char *) "on") == 0) {
        passenger_conf->enabled = 1;
        
        /* Register a placeholder value as upstream address. The real upstream
         * address (the helper agent socket filename) will be set while processing
         * requests, because we can't start the helper agent until config
         * loading is done.
         */
        ngx_memzero(&upstream_url, sizeof(ngx_url_t));
        upstream_url.url = pp_placeholder_upstream_address;
        upstream_url.no_resolve = 1;
        passenger_conf->upstream_config.upstream = ngx_http_upstream_add(cf, &upstream_url, 0);
        if (passenger_conf->upstream_config.upstream == NULL) {
            return NGX_CONF_ERROR;
        }
        
        clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
        clcf->handler = passenger_content_handler;

        if (clcf->name.data != NULL
         && clcf->name.data[clcf->name.len - 1] == '/') {
            clcf->auto_redirect = 1;
        }
    } else if (ngx_strcasecmp(value[1].data, (u_char *) "off") == 0) {
        passenger_conf->enabled = 0;
    } else {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
            "\"passenger_enabled\" must be either set to \"on\" "
            "or \"off\"");

        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}

char *
union_station_filter(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    char  *p = conf;

    ngx_str_t         *value, *s;
    ngx_array_t      **a;
    ngx_conf_post_t   *post;
    char              *message;

    a = (ngx_array_t **) (p + cmd->offset);

    if (*a == NGX_CONF_UNSET_PTR) {
        *a = ngx_array_create(cf->pool, 4, sizeof(ngx_str_t));
        if (*a == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    s = ngx_array_push(*a);
    if (s == NULL) {
        return NGX_CONF_ERROR;
    }

    value = cf->args->elts;

    *s = value[1];

    if (cmd->post) {
        post = cmd->post;
        return post->post_handler(cf, post, s);
    }

    message = passenger_filter_validate((const char *) value[1].data, value[1].len);
    if (message != NULL) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
            "Union Station filter syntax error: %s; ",
            message);
        free(message);
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}

static char *
rails_framework_spawner_idle_time(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_conf_log_error(NGX_LOG_ALERT, cf, 0, "The 'rails_framework_spawner_idle_time' "
        "directive is deprecated; please set 'passenger_max_preloader_idle_time' instead");
    return NGX_CONF_OK;
}

static char *
passenger_use_global_queue(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_conf_log_error(NGX_LOG_ALERT, cf, 0, "The 'passenger_use_global_queue' "
        "directive is obsolete and doesn't do anything anymore. Global queuing "
        "is now always enabled. Please remove this configuration directive.");
    return NGX_CONF_OK;
}

static char *
set_null_terminated_keyval_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    char  *p = conf;

    ngx_str_t         *value;
    ngx_array_t      **a;
    ngx_keyval_t      *kv;
    ngx_conf_post_t   *post;
    u_char            *last;

    a = (ngx_array_t **) (p + cmd->offset);

    if (*a == NULL) {
        *a = ngx_array_create(cf->pool, 4, sizeof(ngx_keyval_t));
        if (*a == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    kv = ngx_array_push(*a);
    if (kv == NULL) {
        return NGX_CONF_ERROR;
    }

    value = cf->args->elts;

    kv->key.data = ngx_palloc(cf->pool, value[1].len + 1);
    kv->key.len  = value[1].len + 1;
    last = ngx_copy(kv->key.data, value[1].data, value[1].len);
    *last = '\0';
    
    kv->value.data = ngx_palloc(cf->pool, value[2].len + 1);
    kv->value.len  = value[2].len + 1;
    last = ngx_copy(kv->value.data, value[2].data, value[2].len);
    *last = '\0';

    if (cmd->post) {
        post = cmd->post;
        return post->post_handler(cf, post, kv);
    }

    return NGX_CONF_OK;
}


const ngx_command_t passenger_commands[] = {

    /******** Main config ********/

    { ngx_string("passenger_root"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, root_dir),
      NULL },

    { ngx_string("passenger_ctl"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE2,
      set_null_terminated_keyval_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, ctl),
      NULL },

    { ngx_string("passenger_ruby"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, default_ruby),
      NULL },

    { ngx_string("passenger_log_level"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, log_level),
      NULL },

    { ngx_string("passenger_debug_log_file"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, debug_log_file),
      NULL },

    { ngx_string("passenger_temp_dir"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, temp_dir),
      NULL },

    { ngx_string("passenger_pre_start"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_array_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, prestart_uris),
      NULL },

    { ngx_string("passenger_abort_on_startup_error"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_FLAG,
      ngx_conf_set_flag_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, abort_on_startup_error),
      NULL },

    { ngx_string("passenger_max_pool_size"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, max_pool_size),
      NULL },

    { ngx_string("passenger_pool_idle_time"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, pool_idle_time),
      NULL },

    { ngx_string("passenger_user_switching"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_FLAG,
      ngx_conf_set_flag_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, user_switching),
      NULL },

    { ngx_string("passenger_default_user"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, default_user),
      NULL },

    { ngx_string("passenger_default_group"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, default_group),
      NULL },

    { ngx_string("passenger_analytics_log_user"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, analytics_log_user),
      NULL },

    { ngx_string("passenger_analytics_log_group"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, analytics_log_group),
      NULL },

    { ngx_string("union_station_gateway_address"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, union_station_gateway_address),
      NULL },

    { ngx_string("union_station_gateway_port"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, union_station_gateway_port),
      NULL },

    { ngx_string("union_station_gateway_cert"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, union_station_gateway_cert),
      NULL },

    { ngx_string("union_station_proxy_address"),
      NGX_HTTP_MAIN_CONF | NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_MAIN_CONF_OFFSET,
      offsetof(passenger_main_conf_t, union_station_proxy_address),
      NULL },

    /******** Per-location config ********/

    #include "ConfigurationCommands.c"

    ngx_null_command
};

