Intial Commit

nodered/rootfs/data/node_modules/circular-buffer/index.js

@@ -0,0 +1,78 @@
+function CircularBuffer(capacity){
+	if(!(this instanceof CircularBuffer))return new CircularBuffer(capacity);
+	if(typeof capacity=="object"&&
+		Array.isArray(capacity["_buffer"])&&
+		typeof capacity._capacity=="number"&&
+		typeof capacity._first=="number"&&
+		typeof capacity._size=="number"){
+		for(var prop in capacity){
+			if(capacity.hasOwnProperty(prop))this[prop]=capacity[prop];
+		}
+	} else {
+		if(typeof capacity!="number"||capacity%1!=0||capacity<1)
+			throw new TypeError("Invalid capacity");
+		this._buffer=new Array(capacity);
+		this._capacity=capacity;
+		this._first=0;
+		this._size=0;
+	}
+}
+
+CircularBuffer.prototype={
+	size:function(){return this._size;},
+	capacity:function(){return this._capacity;},
+	enq:function(value){
+		if(this._first>0)this._first--; else this._first=this._capacity-1;
+		this._buffer[this._first]=value;
+		if(this._size<this._capacity)this._size++;
+	},
+	push:function(value){
+		if(this._size==this._capacity){
+			this._buffer[this._first]=value;
+			this._first=(this._first+1)%this._capacity;
+		} else {
+			this._buffer[(this._first+this._size)%this._capacity]=value;
+			this._size++;
+		}
+	},
+	deq:function(){
+		if(this._size==0)throw new RangeError("dequeue on empty buffer");
+		var value=this._buffer[(this._first+this._size-1)%this._capacity];
+		this._size--;
+		return value;
+	},
+	pop:function(){return this.deq();},
+	shift:function(){
+		if(this._size==0)throw new RangeError("shift on empty buffer");
+		var value=this._buffer[this._first];
+		if(this._first==this._capacity-1)this._first=0; else this._first++;
+		this._size--;
+		return value;
+	},
+	get:function(start,end){
+		if(this._size==0&&start==0&&(end==undefined||end==0))return [];
+		if(typeof start!="number"||start%1!=0||start<0)throw new TypeError("Invalid start");
+		if(start>=this._size)throw new RangeError("Index past end of buffer: "+start);
+
+		if(end==undefined)return this._buffer[(this._first+start)%this._capacity];
+
+		if(typeof end!="number"||end%1!=0||end<0)throw new TypeError("Invalid end");
+		if(end>=this._size)throw new RangeError("Index past end of buffer: "+end);
+
+		if(this._first+start>=this._capacity){
+			//make sure first+start and first+end are in a normal range
+			start-=this._capacity; //becomes a negative number
+			end-=this._capacity;
+		}
+		if(this._first+end<this._capacity)
+			return this._buffer.slice(this._first+start,this._first+end+1);
+		else
+			return this._buffer.slice(this._first+start,this._capacity).concat(this._buffer.slice(0,this._first+end+1-this._capacity));
+	},
+	toarray:function(){
+		if(this._size==0)return [];
+		return this.get(0,this._size-1);
+	}
+};
+
+module.exports=CircularBuffer;