add function format_http_date

HISTORY

@@ -1,5 +1,5 @@
 
-Version 1.40  2018-09-27
+Version 1.40  2018-10-11
   * add function conn_pool_parse_server_info and conn_pool_load_server_info
   * support directive: #@add_annotation, for example:
     #@add_annotation CONFIG_GET /usr/lib/libshmcache.so /etc/libshmcache.conf
@@ -7,6 +7,7 @@ Version 1.40  2018-09-27
   * add json_parser.[hc] for parse json array and map
   * add function fc_strdup
   * add function fc_memmem
+  * add function format_http_date
 
 Version 1.39  2018-07-31
   * add #@function REPLACE_VARS

src/shared_func.c

@@ -2811,3 +2811,13 @@ const char *fc_memmem(const string_t *str, const string_t *needle)
 
     return NULL;
 }
+
+char *format_http_date(time_t t, BufferInfo *buffer)
+{
+    struct tm tm_info;
+
+    gmtime_r(&t, &tm_info);
+    buffer->length = strftime(buffer->buff, buffer->alloc_size,
+            "%a, %d %b %Y %H:%M:%S GMT", &tm_info);
+    return buffer->buff;
+}

src/shared_func.h

@@ -832,6 +832,14 @@ char *fc_strdup(const char *str, const int len);
 */
 const char *fc_memmem(const string_t *str, const string_t *needle);
 
+/** format HTTP Date as: Sat, 11 Mar 2017 21:49:51 GMT
+ *  parameters:
+ *  	t: the time to format
+ *      buffer: the buffer
+ *  return: formatted GMT date string
+*/
+char *format_http_date(time_t t, BufferInfo *buffer);
+
 #ifdef __cplusplus
 }
 #endif