Initial commit; code appears to be working...

LICENSE.md

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+The MIT License (MIT)
+
+Copyright (c) 2013. Blake C. Miner.
+http://blakeminer.com
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

index.js

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+//Intel Hex record types
+const DATA = 0,
+	END_OF_FILE = 1,
+	EXT_SEGMENT_ADDR = 2,
+	START_SEGMENT_ADDR = 3,
+	EXT_LINEAR_ADDR = 4,
+	START_LINEAR_ADDR = 5;
+
+const EMPTY_VALUE = 0xFF;
+
+/* intel_hex.parse(data)
+	`data` - Intel Hex file (string in ASCII format or Buffer Object)
+	`bufferSize` - the size of the Buffer containing the data (optional)
+	
+	returns an Object with the following properties:
+		- data - data as a Buffer Object, padded with 0xFF
+			where data is empty.
+		- startSegmentAddress - the address provided by the last
+			start segment address record; null, if not given
+		- startLinearAddress - the address provided by the last
+			start linear address record; null, if not given
+	Special thanks to: http://en.wikipedia.org/wiki/Intel_HEX
+*/
+exports.parse = function parseIntelHex(data, bufferSize) {
+	if(data instanceof Buffer)
+		data = data.toString("ascii");
+	//Initialization
+	var buf = new Buffer(bufferSize || 8192),
+		bufLength = 0, //Length of data in the buffer
+		highAddress = 0, //upper address
+		startSegmentAddress = null,
+		startLinearAddress = null,
+		lineNum = 0, //Line number in the Intel Hex string
+		pos = 0; //Current position in the Intel Hex string
+	const SMALLEST_LINE = 11;
+	while(pos + SMALLEST_LINE <= data.length)
+	{
+		//Parse an entire line
+		if(data.charAt(pos++) != ":")
+			throw new Error("Line " + (lineNum+1) +
+				" does not start with a colon (:).");
+		else
+			lineNum++;
+		//Number of bytes (hex digit pairs) in the data field
+		var dataLength = parseInt(data.substr(pos, 2), 16);
+		pos += 2;
+		//Get 16-bit address (big-endian)
+		var lowAddress = parseInt(data.substr(pos, 4), 16);
+		pos += 4;
+		//Record type
+		var recordType = parseInt(data.substr(pos, 2), 16);
+		pos += 2;
+		//Data field (hex-encoded string)
+		var dataField = data.substr(pos, dataLength * 2),
+			dataFieldBuf = new Buffer(dataField, "hex");
+		pos += dataLength * 2;
+		//Checksum
+		var checksum = parseInt(data.substr(pos, 2), 16);
+		pos += 2;
+		//Validate checksum
+		var calcChecksum = (dataLength + (lowAddress >> 8) +
+			lowAddress + recordType) & 0xFF;
+		for(var i = 0; i < dataLength; i++)
+			calcChecksum = (calcChecksum + dataFieldBuf[i]) & 0xFF;
+		calcChecksum = 0x100 - calcChecksum;
+		if(checksum != calcChecksum)
+			throw new Error("Invalid checksum on line " + lineNum +
+				": got " + checksum + ", but expected " + calcChecksum);
+		//Parse the record based on its recordType
+		switch(recordType)
+		{
+			case DATA:
+				var absoluteAddress = highAddress + lowAddress;
+				//Expand buf, if necessary
+				if(absoluteAddress + dataLength >= buf.length)
+				{
+					var tmp = new Buffer((absoluteAddress + dataLength) * 2);
+					buf.copy(tmp, 0, 0, bufLength);
+					buf = tmp;
+				}
+				//Write over skipped bytes with EMPTY_VALUE
+				if(absoluteAddress > bufLength)
+					buf.fill(EMPTY_VALUE, bufLength, absoluteAddress);
+				//Write the dataFieldBuf to buf
+				dataFieldBuf.copy(buf, absoluteAddress);
+				bufLength = Math.max(bufLength, absoluteAddress + dataLength);
+				break;
+			case END_OF_FILE:
+				if(dataLength != 0)
+					throw new Error("Invalid EOF record on line " +
+						lineNum + ".");
+				return {
+					"data": buf.slice(0, bufLength),
+					"startSegmentAddress": startSegmentAddress,
+					"startLinearAddress": startLinearAddress
+				};
+				break;
+			case EXT_SEGMENT_ADDR:
+				if(dataLength != 2 || lowAddress != 0)
+					throw new Error("Invalid extended segment address record on line " +
+						lineNum + ".");
+				highAddress = parseInt(dataField, 16) << 4;
+				break;
+			case START_SEGMENT_ADDR:
+				if(dataLength != 4 || lowAddress != 0)
+					throw new Error("Invalid start segment address record on line " +
+						lineNum + ".");
+				startSegmentAddress = parseInt(dataField, 16);
+				break;
+			case EXT_LINEAR_ADDR:
+				if(dataLength != 2 || lowAddress != 0)
+					throw new Error("Invalid extended linear address record on line " +
+						lineNum + ".");
+				highAddress = parseInt(dataField, 16) << 16;
+				break;
+			case START_LINEAR_ADDR:
+				if(dataLength != 4 || lowAddress != 0)
+					throw new Error("Invalid start linear address record on line " +
+						lineNum + ".");
+				startLinearAddress = parseInt(dataField, 16);
+				break;
+			default:
+				throw new Error("Invalid record type (" + recordType +
+					") on line " + lineNum);
+				break;
+		}
+		//Advance to the next line
+		if(data.charAt(pos) == "\r")
+			pos++;
+		if(data.charAt(pos) == "\n")
+			pos++;
+	}
+	throw new Error("Unexpected end of input: missing or invalid EOF record.");
+};

package.json

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+{
+	"name": "intel-hex",
+	"version": "0.1.0",
+	"description": "A JavaScript parser/writer for Intel HEX file format.",
+	"main": "index.js",
+	"scripts": {
+		"test": "echo \"Error: no test specified\" && exit 1"
+	},
+	"repository": {
+		"type": "git",
+		"url": "https://github.com/bminer/intel-hex.js.git"
+	},
+	"keywords": [
+		"intel",
+		"hex",
+		"parser",
+		"reader",
+		"writer"
+	],
+	"author": "Blake Miner <[email protected]>",
+	"license": "MIT",
+	"readmeFilename": "README.md"
+}