[PATCH] Limit conn: Added "off" parameter to the 'limit_conn' directive

[Pavel V. Rochnyack]

# HG changeset patch
# User Pavel V. Rochnyack <pavel2000 at ngs.ru>
# Date 1454835814 -21600
# Node ID b4748ebdd06ba79aa27e0c54fc1d627d13966bed
# Parent  3577c021f21eb4de6d09c1d624ba77ee9ee1eb6d
Limit conn: Added "off" parameter to the 'limit_conn' directive.

Added support for inherited "limit_conn" directives disable.

diff -r 3577c021f21e -r b4748ebdd06b src/http/modules/ngx_http_limit_conn_module.c
--- a/src/http/modules/ngx_http_limit_conn_module.c	Fri Feb 05 21:48:25 2016 +0300
+++ b/src/http/modules/ngx_http_limit_conn_module.c	Sun Feb 07 15:03:34 2016 +0600
@@ -40,6 +40,7 @@ typedef struct {
     ngx_array_t                limits;
     ngx_uint_t                 log_level;
     ngx_uint_t                 status_code;
+    ngx_uint_t                 off;            /* unsigned  off:1 */
 } ngx_http_limit_conn_conf_t;
 
 
@@ -82,7 +83,7 @@ static ngx_command_t  ngx_http_limit_con
       NULL },
 
     { ngx_string("limit_conn"),
-      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE2,
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE12,
       ngx_http_limit_conn,
       NGX_HTTP_LOC_CONF_OFFSET,
       0,
@@ -160,6 +161,10 @@ ngx_http_limit_conn_handler(ngx_http_req
     lccf = ngx_http_get_module_loc_conf(r, ngx_http_limit_conn_module);
     limits = lccf->limits.elts;
 
+    if (lccf->off) {
+        return NGX_DECLINED;
+    }
+
     for (i = 0; i < lccf->limits.nelts; i++) {
         ctx = limits[i].shm_zone->data;
 
@@ -466,6 +471,7 @@ ngx_http_limit_conn_create_conf(ngx_conf
 
     conf->log_level = NGX_CONF_UNSET_UINT;
     conf->status_code = NGX_CONF_UNSET_UINT;
+    conf->off = NGX_CONF_UNSET_UINT;
 
     return conf;
 }
@@ -477,7 +483,9 @@ ngx_http_limit_conn_merge_conf(ngx_conf_
     ngx_http_limit_conn_conf_t *prev = parent;
     ngx_http_limit_conn_conf_t *conf = child;
 
-    if (conf->limits.elts == NULL) {
+    ngx_conf_merge_uint_value(conf->off, prev->off, 0);
+
+    if (conf->off == 0 && conf->limits.elts == NULL) {
         conf->limits = prev->limits;
     }
 
@@ -603,6 +611,35 @@ ngx_http_limit_conn(ngx_conf_t *cf, ngx_
 
     value = cf->args->elts;
 
+    ngx_conf_merge_uint_value(lccf->off, lccf->off, 0);
+
+    if (ngx_strcmp(value[1].data, "off") == 0) {
+        if (cf->args->nelts != 2) {
+            return "has invalid number of arguments";
+        }
+
+        if (lccf->off || lccf->limits.elts) {
+            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                               "\"limit_conn off\" cannot be used with other "
+                               "\"limit_conn\" directives on the same level");
+            return NGX_CONF_ERROR;
+        }
+
+        lccf->off = 1;
+        return NGX_CONF_OK;
+    }
+
+    if (cf->args->nelts != 3) {
+        return "has invalid number of arguments";
+    }
+
+    if (lccf->off) {
+        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                           "\"limit_conn off\" cannot be used with other "
+                           "\"limit_conn\" directives on the same level");
+        return NGX_CONF_ERROR;
+    }
+
     shm_zone = ngx_shared_memory_add(cf, &value[1], 0,
                                      &ngx_http_limit_conn_module);
     if (shm_zone == NULL) {