set_rotate

config

@@ -7,8 +7,8 @@ fi
 
 ngx_addon_name=ngx_http_set_misc_module
 HTTP_AUX_FILTER_MODULES="$HTTP_AUX_FILTER_MODULES ngx_http_set_misc_module"
-NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/src/ngx_http_set_base32.c $ngx_addon_dir/src/ngx_http_set_default_value.c $ngx_addon_dir/src/ngx_http_set_hashed_upstream.c $ngx_addon_dir/src/ngx_http_set_quote_sql.c $ngx_addon_dir/src/ngx_http_set_quote_json.c $ngx_addon_dir/src/ngx_http_set_unescape_uri.c $ngx_addon_dir/src/ngx_http_set_misc_module.c $ngx_addon_dir/src/ngx_http_set_escape_uri.c $ngx_addon_dir/src/ngx_http_set_hash.c $ngx_addon_dir/src/ngx_http_set_local_today.c $ngx_addon_dir/src/ngx_http_set_hex.c $ngx_addon_dir/src/ngx_http_set_base64.c $ngx_addon_dir/src/ngx_http_set_random.c"
-NGX_ADDON_DEPS="$NGX_ADDON_DEPS $ngx_addon_dir/src/ddebug.h $ngx_addon_dir/src/ngx_http_set_default_value.h $ngx_addon_dir/src/ngx_http_set_hashed_upstream.h $ngx_addon_dir/src/ngx_http_set_quote_sql.h $ngx_addon_dir/src/ngx_http_set_quote_json.h $ngx_addon_dir/src/ngx_http_set_unescape_uri.h $ngx_addon_dir/src/ngx_http_set_escape_uri.h $ngx_addon_dir/src/ngx_http_set_hash.h $ngx_addon_dir/src/ngx_http_set_local_today.h $ngx_addon_dir/src/ngx_http_set_hex.h $ngx_addon_dir/src/ngx_http_set_base64.h $ngx_addon_dir/src/ngx_http_set_random.h $ngx_addon_dir/src/ngx_http_set_misc_module.h"
+NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/src/ngx_http_set_base32.c $ngx_addon_dir/src/ngx_http_set_default_value.c $ngx_addon_dir/src/ngx_http_set_hashed_upstream.c $ngx_addon_dir/src/ngx_http_set_quote_sql.c $ngx_addon_dir/src/ngx_http_set_quote_json.c $ngx_addon_dir/src/ngx_http_set_unescape_uri.c $ngx_addon_dir/src/ngx_http_set_misc_module.c $ngx_addon_dir/src/ngx_http_set_escape_uri.c $ngx_addon_dir/src/ngx_http_set_hash.c $ngx_addon_dir/src/ngx_http_set_local_today.c $ngx_addon_dir/src/ngx_http_set_hex.c $ngx_addon_dir/src/ngx_http_set_base64.c $ngx_addon_dir/src/ngx_http_set_random.c $ngx_addon_dir/src/ngx_http_set_rotate.c"
+NGX_ADDON_DEPS="$NGX_ADDON_DEPS $ngx_addon_dir/src/ddebug.h $ngx_addon_dir/src/ngx_http_set_default_value.h $ngx_addon_dir/src/ngx_http_set_hashed_upstream.h $ngx_addon_dir/src/ngx_http_set_quote_sql.h $ngx_addon_dir/src/ngx_http_set_quote_json.h $ngx_addon_dir/src/ngx_http_set_unescape_uri.h $ngx_addon_dir/src/ngx_http_set_escape_uri.h $ngx_addon_dir/src/ngx_http_set_hash.h $ngx_addon_dir/src/ngx_http_set_local_today.h $ngx_addon_dir/src/ngx_http_set_hex.h $ngx_addon_dir/src/ngx_http_set_base64.h $ngx_addon_dir/src/ngx_http_set_random.h $ngx_addon_dir/src/ngx_http_set_rotate.h $ngx_addon_dir/src/ngx_http_set_misc_module.h"
 
 if [ $USE_OPENSSL = YES ]; then
     NGX_ADDON_DEPS="$NGX_ADDON_DEPS $ngx_addon_dir/src/ngx_http_set_hmac.h"

doc/HttpSetMiscModule.wiki

@@ -748,6 +748,38 @@ For now, there's no way to configure a custom random generator seed.
 
 Behind the scene, it makes use of the standard C function <code>rand()</code>.
 
+== set_rotate ==
+'''syntax:''' ''set_random $value <from> <to>''
+
+'''default:''' ''no''
+
+'''context:''' ''location, location if''
+
+'''phase:''' ''rewrite''
+
+Increments <code>$value</code> but keeps it in range from <code>$from</code> to <code>$to</code>. 
+If <code>$value</code> is greater than <code>$to</code> or less than <code>$from</code> is will be 
+set to <code>$from</code> value.
+
+Only non-negative numbers are allowed for the <code><from></code> and <code><to></code> arguments.
+
+When <code><$from></code> is greater than <code><$to></code>, their values will be exchanged accordingly.
+
+For instance,
+
+<geshi lang="nginx">
+	location /rotate {
+	    default_type text/plain;
+	    set $counter $cookie_counter;
+	    set_rotate $counter 1 5;
+	    echo $counter;
+	    add_header Set-Cookie counter=$counter;
+	}
+</geshi>
+
+then request <code>GET /rotate</code> will output next number between 1 and 5 (i.e., 1, 2, 3, 4, 5) on each
+refresh of the page. This directive may be userful for banner rotation purposes.
+
 == set_local_today ==
 '''syntax:''' ''set_local_today $dst''
 

src/ngx_http_set_misc_module.c

@@ -20,6 +20,7 @@
 #include "ngx_http_set_hmac.h"
 #endif
 #include "ngx_http_set_random.h"
+#include "ngx_http_set_rotate.h"
 
 #define NGX_UNESCAPE_URI_COMPONENT  0
 
@@ -146,7 +147,14 @@ static  ndk_set_var_t  ngx_http_set_misc_set_random_filter = {
     2,
     NULL
 };
-
+/*
+static  ndk_set_var_t  ngx_http_set_misc_set_rotate_filter = {
+    NDK_SET_VAR_VALUE,
+    ngx_http_set_misc_set_rotate,
+    2,
+    NULL
+};
+*/
 static ngx_command_t  ngx_http_set_misc_commands[] = {
     {   ngx_string ("set_encode_base64"),
         NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_SIF_CONF
@@ -316,6 +324,14 @@ static ngx_command_t  ngx_http_set_misc_commands[] = {
         0,
         &ngx_http_set_misc_set_random_filter
     },
+    {   ngx_string ("set_rotate"),
+        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_SIF_CONF
+            |NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF|NGX_CONF_TAKE3,
+        ngx_http_set_rotate,
+        0,
+        0,
+        NULL
+    },
 
     ngx_null_command
 };

src/ngx_http_set_rotate.c

@@ -0,0 +1,84 @@
+#ifndef DDEBUG
+#define DDEBUG 0
+#endif
+#include "ddebug.h"
+
+#include <ndk.h>
+#include "ngx_http_set_rotate.h"
+#include <stdlib.h>
+
+ngx_int_t
+ngx_http_set_misc_set_rotate(ngx_http_request_t *r,
+                                ngx_str_t *res, ngx_http_variable_value_t *v)
+{
+    ngx_http_variable_value_t   *rotate_from, *rotate_to, *rotate_num;
+    ngx_int_t                    int_from, int_to, tmp, int_current;
+
+    rotate_num = &v[0];
+    rotate_from = &v[1];
+    rotate_to = &v[2];
+
+//    rotate_from = v;
+//    rotate_to = v + 1;
+
+    int_from = ngx_atoi(rotate_from->data, rotate_from->len);
+    if (int_from == NGX_ERROR) {
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                "set_rotate: bad \"from\" argument: %v", rotate_from);
+        return NGX_ERROR;
+    }
+
+    int_to = ngx_atoi(rotate_to->data, rotate_to->len);
+    if (int_to == NGX_ERROR) {
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                "set_rotate: bad \"to\" argument: %v", rotate_to);
+        return NGX_ERROR;
+    }
+
+    if (int_from > int_to) {
+        tmp = int_from;
+        int_from = int_to;
+        int_to = tmp;
+    }
+
+    int_current = ngx_atoi(rotate_num->data, rotate_num->len);
+    if (int_current == NGX_ERROR) {
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                "set_rotate: bad \"default\" argument: %v", rotate_to);
+        int_current = int_from;
+    }
+
+    int_current++;
+    if(int_current>int_to || int_current<int_from)
+	int_current = int_from;
+
+    res->data = ngx_palloc(r->pool, NGX_INT_T_LEN);
+    if (res->data == NULL) {
+        return NGX_ERROR;
+    }
+
+    res->len = ngx_sprintf(res->data, "%i", int_current) - res->data;
+
+    /* Set all required params */
+    v->valid = 1;
+    v->no_cacheable = 0;
+    v->not_found = 0;
+
+    return NGX_OK;
+}
+
+char *
+ngx_http_set_rotate(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
+{
+    ngx_str_t               *value;
+    ndk_set_var_t            filter;
+
+    value = cf->args->elts;
+
+    filter.type = NDK_SET_VAR_MULTI_VALUE;
+    filter.func = ngx_http_set_misc_set_rotate;
+    filter.size = 3;
+    filter.data = NULL;
+
+    return  ndk_set_var_multi_value_core(cf, &value[1], &value[1], &filter);
+}

src/ngx_http_set_rotate.h

@@ -0,0 +1,9 @@
+#include <ngx_core.h>
+#include <ngx_config.h>
+#include <ngx_http.h>
+
+char * ngx_http_set_rotate(ngx_conf_t *cf, ngx_command_t *cmd,
+        void *conf);
+
+ngx_int_t ngx_http_set_misc_set_rotate(ngx_http_request_t *r,
+        ngx_str_t *res, ngx_http_variable_value_t *v);