1 files changed, 84 insertions, 0 deletions
diff --git a/src/engine/ringbuffer.h b/src/engine/ringbuffer.h
new file mode 100644
index 00000000..3208efbf
--- /dev/null
+++ b/src/engine/ringbuffer.h
@@ -0,0 +1,84 @@
+
+// TODO: remove all the allocations from this class
+class ring_buffer
+{
+public:
+	struct item
+	{
+		item *next;
+		item *prev;
+		int size;
+		unsigned char *data() { return (unsigned char *)(this+1); }
+	};
+	
+	item *first_item;
+	item *last_item;
+	
+	unsigned buffer_size;
+	
+	ring_buffer()
+	{
+		first_item = 0;
+		last_item = 0;
+		buffer_size = 0;
+	}
+	
+	~ring_buffer()
+	{
+		reset();
+	}
+	
+	void reset()
+	{
+		// clear all
+		while(first())
+			pop_first();
+	}
+	
+	void *alloc(int size)
+	{
+		item *i = (item*)mem_alloc(sizeof(item)+size, 1);
+		i->size = size;
+		
+		i->prev = last_item;
+		i->next = 0;
+		if(last_item)
+			last_item->next = i;
+		else
+			first_item = i;
+		last_item = i;
+		
+		buffer_size += size;
+		return i->data();
+	}
+	
+	item *first()
+	{
+		return first_item;
+	}
+
+	/*
+	void *peek_data()
+	{
+		if(!first)
+			return 0;
+		return (void*)(first+1);
+	}*/
+	
+	void pop_first()
+	{
+		if(first_item)
+		{
+			item *next = first_item->next;
+			buffer_size -= first_item->size;
+			mem_free(first_item);
+			first_item = next;
+			if(first_item)
+				first_item->prev = 0;
+			else
+				last_item = 0;
+		}
+	}
+	
+	unsigned size() { return buffer_size; }
+};