support "touch" command

src/memc_touch.rl

@@ -0,0 +1,17 @@
+%%{
+    machine memc_touch;
+
+    alphtype short;
+
+    include memc_common "memc_common.rl";
+
+    response = "TOUCHED\r\n"
+             | "NOT_FOUND\r\n" @handle_not_found
+             | error
+             ;
+
+    main := response @finalize
+         ;
+
+}%%
+

src/ngx_http_memc_handler.c

@@ -281,6 +281,13 @@ ngx_http_memc_handler(ngx_http_request_t *r)
         u->input_filter_init = ngx_http_memc_empty_filter_init;
         u->input_filter = ngx_http_memc_empty_filter;
 
+    } else if (memc_cmd == ngx_http_memc_cmd_touch) {
+        u->create_request = ngx_http_memc_create_touch_cmd_request;
+        u->process_header = ngx_http_memc_process_simple_header;
+
+        u->input_filter_init = ngx_http_memc_empty_filter_init;
+        u->input_filter = ngx_http_memc_empty_filter;
+
     } else {
         ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
             "assertion failed: command \"%v\" does not have proper "
@@ -297,7 +304,8 @@ ngx_http_memc_handler(ngx_http_request_t *r)
 
     if (is_storage_cmd
             || memc_cmd == ngx_http_memc_cmd_flush_all
-            || memc_cmd == ngx_http_memc_cmd_delete)
+            || memc_cmd == ngx_http_memc_cmd_delete
+            || memc_cmd == ngx_http_memc_cmd_touch)
     {
         exptime_vv = ngx_http_get_indexed_variable(r, mmcf->exptime_index);
 

src/ngx_http_memc_module.h

@@ -33,6 +33,8 @@ typedef enum {
 
     ngx_http_memc_cmd_flush_all,
     ngx_http_memc_cmd_version,
+
+    ngx_http_memc_cmd_touch,
     /* ngx_http_memc_cmd_verbosity, */
 
     /* we do not want to support the "quit" command here */

src/ngx_http_memc_request.c

@@ -569,3 +569,78 @@ ngx_http_memc_create_incr_decr_cmd_request(ngx_http_request_t *r)
 
     return NGX_OK;
 }
+
+
+ngx_int_t
+ngx_http_memc_create_touch_cmd_request(ngx_http_request_t *r)
+{
+    size_t                          len;
+    ngx_buf_t                      *b;
+    ngx_http_memc_ctx_t            *ctx;
+    ngx_chain_t                    *cl;
+    uintptr_t                       escape;
+    ngx_http_variable_value_t      *key_vv;
+    ngx_http_variable_value_t      *exptime_vv;
+
+    ctx = ngx_http_get_module_ctx(r, ngx_http_memc_module);
+
+    /* prepare the "key" argument */
+
+    key_vv = ctx->memc_key_vv;
+
+    if (key_vv == NULL || key_vv->not_found || key_vv->len == 0) {
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                      "the \"$memc_key\" variable is not set");
+        return NGX_ERROR;
+    }
+
+    escape = 2 * ngx_escape_uri(NULL, key_vv->data, key_vv->len,
+            NGX_ESCAPE_MEMCACHED);
+
+    /* prepare the "exptime" argument */
+
+    exptime_vv = ctx->memc_exptime_vv;
+
+    if (exptime_vv == NULL || exptime_vv->not_found || exptime_vv->len == 0) {
+        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                      "the \"$memc_exptime\" variable is not set");
+        return NGX_ERROR;
+    }
+
+    len = ctx->cmd_str.len + sizeof(' ') + key_vv->len + escape + sizeof(' ')
+        + exptime_vv->len + sizeof(CRLF) - 1;
+
+    b = ngx_create_temp_buf(r->pool, len);
+    if (b == NULL) {
+        return NGX_ERROR;
+    }
+
+    cl = ngx_alloc_chain_link(r->pool);
+    if (cl == NULL) {
+        return NGX_ERROR;
+    }
+
+    cl->buf = b;
+    cl->next = NULL;
+
+    r->upstream->request_bufs = cl;
+
+    b->last = ngx_copy(b->last, ctx->cmd_str.data, ctx->cmd_str.len);
+
+    *b->last++ = ' ';
+
+    if (escape == 0) {
+        b->last = ngx_copy(b->last, key_vv->data, key_vv->len);
+
+    } else {
+        b->last = (u_char *) ngx_escape_uri(b->last, key_vv->data, key_vv->len,
+                                            NGX_ESCAPE_MEMCACHED);
+    }
+
+    *b->last++ = ' ';
+    b->last = ngx_copy(b->last, exptime_vv->data, exptime_vv->len);
+
+    *b->last++ = CR; *b->last++ = LF;
+
+    return NGX_OK;
+}

src/ngx_http_memc_request.h

@@ -22,6 +22,7 @@ ngx_int_t ngx_http_memc_create_delete_cmd_request(ngx_http_request_t *r);
 
 ngx_int_t ngx_http_memc_create_incr_decr_cmd_request(ngx_http_request_t *r);
 
+ngx_int_t ngx_http_memc_create_touch_cmd_request(ngx_http_request_t *r);
 
 #endif /* NGX_HTTP_MEMC_REQUEST_H */