typedef struct
{
    ngx_str_t hello_string;
    ngx_int_t hello_counter;
}ngx_http_hello_loc_conf_t;

static ngx_command_t ngx_http_hello_commands[] = {
   {
        ngx_string("hello_string"),
        NGX_HTTP_LOC_CONF|NGX_CONF_NOARGS|NGX_CONF_TAKE1,
        ngx_http_hello_string,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_hello_loc_conf_t, hello_string),
        NULL },

    {
        ngx_string("hello_counter"),
        NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_http_hello_counter,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_hello_loc_conf_t, hello_counter),
        NULL },

    ngx_null_command
};

struct ngx_command_s {
    ngx_str_t             name;
    ngx_uint_t            type;
    char               *(*set)(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
    ngx_uint_t            conf;
    ngx_uint_t            offset;
    void                 *post;
};

char *(*set)(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);

typedef struct {
    ngx_int_t   (*preconfiguration)(ngx_conf_t *cf);
    ngx_int_t   (*postconfiguration)(ngx_conf_t *cf);

    void       *(*create_main_conf)(ngx_conf_t *cf);
    char       *(*init_main_conf)(ngx_conf_t *cf, void *conf);

    void       *(*create_srv_conf)(ngx_conf_t *cf);
    char       *(*merge_srv_conf)(ngx_conf_t *cf, void *prev, void *conf);

    void       *(*create_loc_conf)(ngx_conf_t *cf);
    char       *(*merge_loc_conf)(ngx_conf_t *cf, void *prev, void *conf);
} ngx_http_module_t;

static ngx_http_module_t ngx_http_hello_module_ctx = {
    NULL,                          /* preconfiguration */
    ngx_http_hello_init,           /* postconfiguration */

    NULL,                          /* create main configuration */
    NULL,                          /* init main configuration */

    NULL,                          /* create server configuration */
    NULL,                          /* merge server configuration */

    ngx_http_hello_create_loc_conf, /* create location configuration */
    NULL                        /* merge location configuration */
};

ngx_module_t ngx_http_hello_module = {
    NGX_MODULE_V1,
    &ngx_http_hello_module_ctx,    /* module context */
    ngx_http_hello_commands,       /* module directives */
    NGX_HTTP_MODULE,               /* module type */
    NULL,                          /* init master */
    NULL,                          /* init module */
    NULL,                          /* init process */
    NULL,                          /* init thread */
    NULL,                          /* exit thread */
    NULL,                          /* exit process */
    NULL,                          /* exit master */
    NGX_MODULE_V1_PADDING
};

static ngx_int_t
ngx_http_hello_init(ngx_conf_t *cf)
{
        ngx_http_handler_pt        *h;
        ngx_http_core_main_conf_t  *cmcf;

        cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);

        h = ngx_array_push(&cmcf->phases[NGX_HTTP_CONTENT_PHASE].handlers);
        if (h == NULL) {
                return NGX_ERROR;
        }

        *h = ngx_http_hello_handler;

        return NGX_OK;
}

static char *
ngx_http_circle_gif(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
        ngx_http_core_loc_conf_t  *clcf;

        clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
        clcf->handler = ngx_http_circle_gif_handler;

        return NGX_CONF_OK;
}

location /test {
                hello_string jizhao;
                hello_counter on;
}

static ngx_int_t ngx_http_access_handler(ngx_http_request_t *r);
static ngx_int_t ngx_http_access_inet(ngx_http_request_t *r,
        ngx_http_access_loc_conf_t *alcf, in_addr_t addr);
#if (NGX_HAVE_INET6)
static ngx_int_t ngx_http_access_inet6(ngx_http_request_t *r,
        ngx_http_access_loc_conf_t *alcf, u_char *p);
#endif
static ngx_int_t ngx_http_access_found(ngx_http_request_t *r, ngx_uint_t deny);
static char *ngx_http_access_rule(ngx_conf_t *cf, ngx_command_t *cmd,
        void *conf);
static void *ngx_http_access_create_loc_conf(ngx_conf_t *cf);
static char *ngx_http_access_merge_loc_conf(ngx_conf_t *cf,
        void *parent, void *child);
static ngx_int_t ngx_http_access_init(ngx_conf_t *cf);

ngx_http_module_t  ngx_http_static_module_ctx = {
        NULL,                                  /* preconfiguration */
        ngx_http_static_init,                  /* postconfiguration */

        NULL,                                  /* create main configuration */
        NULL,                                  /* init main configuration */

        NULL,                                  /* create server configuration */
        NULL,                                  /* merge server configuration */

        NULL,                                  /* create location configuration */
        NULL                                   /* merge location configuration */
};

static ngx_int_t
ngx_http_static_init(ngx_conf_t *cf)
{
        ngx_http_handler_pt        *h;
        ngx_http_core_main_conf_t  *cmcf;

        cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);

        h = ngx_array_push(&cmcf->phases[NGX_HTTP_CONTENT_PHASE].handlers);
        if (h == NULL) {
                return NGX_ERROR;
        }

        *h = ngx_http_static_handler;

        return NGX_OK;
}

static ngx_int_t
ngx_http_static_handler(ngx_http_request_t *r)
{
        u_char                    *last, *location;
        size_t                     root, len;
        ngx_str_t                  path;
        ngx_int_t                  rc;
        ngx_uint_t                 level;
        ngx_log_t                 *log;
        ngx_buf_t                 *b;
        ngx_chain_t                out;
        ngx_open_file_info_t       of;
        ngx_http_core_loc_conf_t  *clcf;

        if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD|NGX_HTTP_POST))) {
                return NGX_HTTP_NOT_ALLOWED;
        }

        if (r->uri.data[r->uri.len - 1] == '/') {
                return NGX_DECLINED;
        }

        log = r->connection->log;

        /*
         * ngx_http_map_uri_to_path() allocates memory for terminating ''
         * so we do not need to reserve memory for '/' for possible redirect
         */

        last = ngx_http_map_uri_to_path(r, &path, &root, 0);
        if (last == NULL) {
                return NGX_HTTP_INTERNAL_SERVER_ERROR;
        }

        path.len = last - path.data;

        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, log, 0,
                                   "http filename: "%s"", path.data);

        clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

        ngx_memzero(&of, sizeof(ngx_open_file_info_t));

        of.read_ahead = clcf->read_ahead;
        of.directio = clcf->directio;
        of.valid = clcf->open_file_cache_valid;
        of.min_uses = clcf->open_file_cache_min_uses;
        of.errors = clcf->open_file_cache_errors;
        of.events = clcf->open_file_cache_events;

        if (ngx_http_set_disable_symlinks(r, clcf, &path, &of) != NGX_OK) {
                return NGX_HTTP_INTERNAL_SERVER_ERROR;
        }

        if (ngx_open_cached_file(clcf->open_file_cache, &path, &of, r->pool)
                != NGX_OK)
        {
                switch (of.err) {

                case 0:
                        return NGX_HTTP_INTERNAL_SERVER_ERROR;

                case NGX_ENOENT:
                case NGX_ENOTDIR:
                case NGX_ENAMETOOLONG:

                        level = NGX_LOG_ERR;
                        rc = NGX_HTTP_NOT_FOUND;
                        break;

                case NGX_EACCES:
#if (NGX_HAVE_OPENAT)
                case NGX_EMLINK:
                case NGX_ELOOP:
#endif

                        level = NGX_LOG_ERR;
                        rc = NGX_HTTP_FORBIDDEN;
                        break;

                default:

                        level = NGX_LOG_CRIT;
                        rc = NGX_HTTP_INTERNAL_SERVER_ERROR;
                        break;
                }

                if (rc != NGX_HTTP_NOT_FOUND || clcf->log_not_found) {
                        ngx_log_error(level, log, of.err,
                                                  "%s "%s" failed", of.failed, path.data);
                }

                return rc;
        }

        r->root_tested = !r->error_page;

        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, log, 0, "http static fd: %d", of.fd);

        if (of.is_dir) {

                ngx_log_debug0(NGX_LOG_DEBUG_HTTP, log, 0, "http dir");

                ngx_http_clear_location(r);

                r->headers_out.location = ngx_palloc(r->pool, sizeof(ngx_table_elt_t));
                if (r->headers_out.location == NULL) {
                        return NGX_HTTP_INTERNAL_SERVER_ERROR;
                }

                len = r->uri.len + 1;

                if (!clcf->alias && clcf->root_lengths == NULL && r->args.len == 0) {
                        location = path.data + clcf->root.len;

                        *last = '/';

                } else {
                        if (r->args.len) {
                                len += r->args.len + 1;
                        }

                        location = ngx_pnalloc(r->pool, len);
                        if (location == NULL) {
                                return NGX_HTTP_INTERNAL_SERVER_ERROR;
                        }

                        last = ngx_copy(location, r->uri.data, r->uri.len);

                        *last = '/';

                        if (r->args.len) {
                                *++last = '?';
                                ngx_memcpy(++last, r->args.data, r->args.len);
                        }
                }

                /*
                 * we do not need to set the r->headers_out.location->hash and
                 * r->headers_out.location->key fields
                 */

                r->headers_out.location->value.len = len;
                r->headers_out.location->value.data = location;

                return NGX_HTTP_MOVED_PERMANENTLY;
        }

#if !(NGX_WIN32) /* the not regular files are probably Unix specific */

        if (!of.is_file) {
                ngx_log_error(NGX_LOG_CRIT, log, 0,
                                          ""%s" is not a regular file", path.data);

                return NGX_HTTP_NOT_FOUND;
        }

#endif

        if (r->method & NGX_HTTP_POST) {
                return NGX_HTTP_NOT_ALLOWED;
        }

        rc = ngx_http_discard_request_body(r);

        if (rc != NGX_OK) {
                return rc;
        }

        log->action = "sending response to client";

        r->headers_out.status = NGX_HTTP_OK;
        r->headers_out.content_length_n = of.size;
        r->headers_out.last_modified_time = of.mtime;

        if (ngx_http_set_content_type(r) != NGX_OK) {
                return NGX_HTTP_INTERNAL_SERVER_ERROR;
        }

        if (r != r->main && of.size == 0) {
                return ngx_http_send_header(r);
        }

        r->allow_ranges = 1;

        /* we need to allocate all before the header would be sent */

        b = ngx_pcalloc(r->pool, sizeof(ngx_buf_t));
        if (b == NULL) {
                return NGX_HTTP_INTERNAL_SERVER_ERROR;
        }

        b->file = ngx_pcalloc(r->pool, sizeof(ngx_file_t));
        if (b->file == NULL) {
                return NGX_HTTP_INTERNAL_SERVER_ERROR;
        }

        rc = ngx_http_send_header(r);

        if (rc == NGX_ERROR || rc > NGX_OK || r->header_only) {
                return rc;
        }

        b->file_pos = 0;
        b->file_last = of.size;

        b->in_file = b->file_last ? 1: 0;
        b->last_buf = (r == r->main) ? 1: 0;
        b->last_in_chain = 1;

        b->file->fd = of.fd;
        b->file->name = path;
        b->file->log = log;
        b->file->directio = of.is_directio;

        out.buf = b;
        out.next = NULL;

        return ngx_http_output_filter(r, &out);
}

static void
ngx_http_log_request(ngx_http_request_t *r)
{
        ngx_uint_t                  i, n;
        ngx_http_handler_pt        *log_handler;
        ngx_http_core_main_conf_t  *cmcf;

        cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);

        log_handler = cmcf->phases[NGX_HTTP_LOG_PHASE].handlers.elts;
        n = cmcf->phases[NGX_HTTP_LOG_PHASE].handlers.nelts;

        for (i = 0; i < n; i++) {
                log_handler[i](r);
        }
}