ngx_http_variables.c

Nginx是一个高性能的HTTP和反向代理服务器

    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = path.data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_server_name(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    ngx_http_core_srv_conf_t  *cscf;

    cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);

    v->len = cscf->server_name.len;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = cscf->server_name.data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_request_method(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    if (r->main->method_name.data) {
        v->len = r->main->method_name.len;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = r->main->method_name.data;

    } else {
        v->not_found = 1;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_remote_user(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    ngx_int_t  rc;

    rc = ngx_http_auth_basic_user(r);

    if (rc == NGX_DECLINED) {
        v->not_found = 1;
        return NGX_OK;
    }

    if (rc == NGX_ERROR) {
        return NGX_ERROR;
    }

    v->len = r->headers_in.user.len;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = r->headers_in.user.data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_body_bytes_sent(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    off_t    sent;
    u_char  *p;

    sent = r->connection->sent - r->header_size;

    if (sent < 0) {
        sent = 0;
    }

    p = ngx_palloc(r->pool, NGX_OFF_T_LEN);
    if (p == NULL) {
        return NGX_ERROR;
    }

    v->len = ngx_sprintf(p, "%O", sent) - p;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = p;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_sent_content_type(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    if (r->headers_out.content_type.len) {
        v->len = r->headers_out.content_type.len;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = r->headers_out.content_type.data;

    } else {
        v->not_found = 1;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_sent_content_length(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    u_char  *p;

    if (r->headers_out.content_length) {
        v->len = r->headers_out.content_length->value.len;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = r->headers_out.content_length->value.data;

        return NGX_OK;
    }

    if (r->headers_out.content_length_n >= 0) {
        p = ngx_palloc(r->pool, NGX_OFF_T_LEN);
        if (p == NULL) {
            return NGX_ERROR;
        }

        v->len = ngx_sprintf(p, "%O", r->headers_out.content_length_n) - p;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = p;

        return NGX_OK;
    }

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_sent_last_modified(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    u_char  *p;

    if (r->headers_out.last_modified) {
        v->len = r->headers_out.last_modified->value.len;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = r->headers_out.last_modified->value.data;

        return NGX_OK;
    }

    if (r->headers_out.last_modified_time >= 0) {
        p = ngx_palloc(r->pool,
                   sizeof("Last-Modified: Mon, 28 Sep 1970 06:00:00 GMT") - 1);
        if (p == NULL) {
            return NGX_ERROR;
        }

        v->len = ngx_http_time(p, r->headers_out.last_modified_time) - p;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = p;

        return NGX_OK;
    }

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_sent_connection(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    size_t   len;
    char    *p;

    if (r->keepalive) {
        len = sizeof("keep-alive") - 1;
        p = "keep-alive";

    } else {
        len = sizeof("close") - 1;
        p = "close";
    }

    v->len = len;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = (u_char *) p;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_sent_keep_alive(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    u_char                    *p;
    ngx_http_core_loc_conf_t  *clcf;

    if (r->keepalive) {
        clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

        if (clcf->keepalive_header) {

            p = ngx_palloc(r->pool, sizeof("timeout=") - 1 + NGX_TIME_T_LEN);
            if (p == NULL) {
                return NGX_ERROR;
            }

            v->len = ngx_sprintf(p, "timeout=%T", clcf->keepalive_header) - p;
            v->valid = 1;
            v->no_cacheable = 0;
            v->not_found = 0;
            v->data = p;

            return NGX_OK;
        }
    }

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_sent_transfer_encoding(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    if (r->chunked) {
        v->len = sizeof("chunked") - 1;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = (u_char *) "chunked";

    } else {
        v->not_found = 1;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_request_completion(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    if (r->request_complete) {
        v->len = 2;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = (u_char *) "OK";

        return NGX_OK;
    }

    v->len = 0;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = (u_char *) "";

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_request_body_file(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    if (r->request_body == NULL || r->request_body->temp_file == NULL) {
        v->not_found = 1;

        return NGX_OK;
    }

    v->len = r->request_body->temp_file->file.name.len;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = r->request_body->temp_file->file.name.data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_variable_nginx_version(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    v->len = sizeof(NGINX_VERSION) - 1;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = (u_char *) NGINX_VERSION;

    return NGX_OK;
}


ngx_int_t
ngx_http_variables_add_core_vars(ngx_conf_t *cf)
{
    ngx_int_t                   rc;
    ngx_http_variable_t        *v;
    ngx_http_core_main_conf_t  *cmcf;

    cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);

    cmcf->variables_keys = ngx_pcalloc(cf->temp_pool,
                                       sizeof(ngx_hash_keys_arrays_t));
    if (cmcf->variables_keys == NULL) {
        return NGX_ERROR;
    }

    cmcf->variables_keys->pool = cf->pool;
    cmcf->variables_keys->temp_pool = cf->pool;

    if (ngx_hash_keys_array_init(cmcf->variables_keys, NGX_HASH_SMALL)
        != NGX_OK)
    {
        return NGX_ERROR;
    }

    for (v = ngx_http_core_variables; v->name.len; v++) {
        rc = ngx_hash_add_key(cmcf->variables_keys, &v->name, v,
                              NGX_HASH_READONLY_KEY);

        if (rc == NGX_OK) {
            continue;
        }

        if (rc == NGX_BUSY) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "conflicting variable name \"%V\"", &v->name);
        }

        return NGX_ERROR;
    }

    return NGX_OK;
}


ngx_int_t
ngx_http_variables_init_vars(ngx_conf_t *cf)
{
    ngx_uint_t                  i, n;
    ngx_hash_key_t             *key;
    ngx_hash_init_t             hash;
    ngx_http_variable_t        *v, *av;
    ngx_http_core_main_conf_t  *cmcf;

    /* set the handlers for the indexed http variables */

    cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);

    v = cmcf->variables.elts;
    key = cmcf->variables_keys->keys.elts;

    for (i = 0; i < cmcf->variables.nelts; i++) {

        for (n = 0; n < cmcf->variables_keys->keys.nelts; n++) {

            av = key[n].value;

            if (av->get_handler
                && v[i].name.len == key[n].key.len
                && ngx_strncmp(v[i].name.data, key[n].key.data, v[i].name.len)
                   == 0)
            {
                v[i].get_handler = av->get_handler;
                v[i].data = av->data;

                av->flags |= NGX_HTTP_VAR_INDEXED;
                v[i].flags = av->flags;

                av->index = i;

                goto next;
            }
        }

        if (ngx_strncmp(v[i].name.data, "http_", 5) == 0) {
            v[i].get_handler = ngx_http_variable_unknown_header_in;
            v[i].data = (uintptr_t) &v[i].name;

            continue;
        }

        if (ngx_strncmp(v[i].name.data, "sent_http_", 10) == 0) {
            v[i].get_handler = ngx_http_variable_unknown_header_out;
            v[i].data = (uintptr_t) &v[i].name;

            continue;
        }

        if (ngx_strncmp(v[i].name.data, "upstream_http_", 14) == 0) {
            v[i].get_handler = ngx_http_upstream_header_variable;
            v[i].data = (uintptr_t) &v[i].name;
            v[i].flags = NGX_HTTP_VAR_NOCACHEABLE;

            continue;
        }

        ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                      "unknown \"%V\" variable", &v[i].name);

        return NGX_ERROR;

    next:
        continue;
    }


    for (n = 0; n < cmcf->variables_keys->keys.nelts; n++) {
        av = key[n].value;

        if (av->flags & NGX_HTTP_VAR_NOHASH) {
            key[n].key.data = NULL;
        }
    }


    hash.hash = &cmcf->variables_hash;
    hash.key = ngx_hash_key;
    hash.max_size = cmcf->variables_hash_max_size;
    hash.bucket_size = cmcf->variables_hash_bucket_size;
    hash.name = "variables_hash";
    hash.pool = cf->pool;
    hash.temp_pool = NULL;

    if (ngx_hash_init(&hash, cmcf->variables_keys->keys.elts,
                      cmcf->variables_keys->keys.nelts)
        != NGX_OK)
    {
        return NGX_ERROR;
    }

    cmcf->variables_keys = NULL;

    return NGX_OK;
}