ext/asciipack/packer.h in asciipack-0.2.2 vs ext/asciipack/packer.h in asciipack-0.2.3

@@ -4,13 +4,47 @@
 #ifndef PACKER_H
 #  define PACKER_H
 
 #include <stdlib.h>
 
+/*
+ * packer:
+ * |      - memsize -      |
+ * +-----------------------+
+ * |     ||           |    |
+ * +-----------------------+
+ * ^mem  ^(tag)    ^mem_end
+ *
+ * main write strings memory.
+ * realloc when will write over size string.
+ * if will write too large stiring,
+ * it is skip and continue write from mem_end.
+ *
+ *
+ * tag:
+ * +--------------------------+
+ * | tag(too large string) |
+ * +--------------------------+ ... 
+ * ^begin                     ^end
+ *
+ * too large string tag to use Copy-on-Write.
+ * tag->next look packer or an another tag.
+ */
+
+struct tag {
+	char* begin;
+	char* end;
+	unsigned int is_reference:1;
+	struct tag* next;
+};
+typedef struct tag tag_t;
+
 struct packer {
-	char* buffer;
-	char* ch;
+	char* mem;
+	char* mem_end;
+	tag_t* tag;
+	tag_t* start;
 	size_t memsize;
 };
 typedef struct packer packer_t;
 
 union unegative_int {
@@ -20,10 +54,10 @@
 	int16_t i16;
 	int32_t i32;
 	int64_t i64;
 };
 
-#define MEMSIZE_INIT 128
+#define MEMSIZE_INIT (1024*128)
 
 #define PACKER(from, name) \
 	packer_t* name; \
 	Data_Get_Struct(from, packer_t, name); \
 	if (name == NULL) { \