first commit

build/node_modules/exif-parser/lib/bufferstream.js

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+function BufferStream(buffer, offset, length, bigEndian) {
+	this.buffer = buffer;
+	this.offset = offset || 0;
+	length = typeof length === 'number' ? length : buffer.length;
+	this.endPosition = this.offset + length;
+	this.setBigEndian(bigEndian);
+}
+
+BufferStream.prototype = {
+	setBigEndian: function(bigEndian) {
+		this.bigEndian = !!bigEndian;
+	},
+	nextUInt8: function() {
+		var value = this.buffer.readUInt8(this.offset);
+		this.offset += 1;
+		return value;
+	},
+	nextInt8: function() {
+		var value = this.buffer.readInt8(this.offset);
+		this.offset += 1;
+		return value;
+	},
+	nextUInt16: function() {
+		var value = this.bigEndian ? this.buffer.readUInt16BE(this.offset) : this.buffer.readUInt16LE(this.offset);
+		this.offset += 2;
+		return value;
+	},
+	nextUInt32: function() {
+		var value = this.bigEndian ? this.buffer.readUInt32BE(this.offset) : this.buffer.readUInt32LE(this.offset);
+		this.offset += 4;
+		return value;
+	},
+	nextInt16: function() {
+		var value = this.bigEndian ? this.buffer.readInt16BE(this.offset) : this.buffer.readInt16LE(this.offset);
+		this.offset += 2;
+		return value;
+	},
+	nextInt32: function() {
+		var value = this.bigEndian ? this.buffer.readInt32BE(this.offset) : this.buffer.readInt32LE(this.offset);
+		this.offset += 4;
+		return value;
+	},
+	nextFloat: function() {
+		var value = this.bigEndian ? this.buffer.readFloatBE(this.offset) : this.buffer.readFloatLE(this.offset);
+		this.offset += 4;
+		return value;
+	},
+	nextDouble: function() {
+		var value = this.bigEndian ? this.buffer.readDoubleBE(this.offset) : this.buffer.readDoubleLE(this.offset);
+		this.offset += 8;
+		return value;
+	},
+	nextBuffer: function(length) {
+		var value = this.buffer.slice(this.offset, this.offset + length);
+		this.offset += length;
+		return value;
+	},
+	remainingLength: function() {
+		return this.endPosition - this.offset;
+	},
+	nextString: function(length) {
+		var value = this.buffer.toString('utf8', this.offset, this.offset + length);
+		this.offset += length;
+		return value;
+	},
+	mark: function() {
+		var self = this;
+		return {
+			openWithOffset: function(offset) {
+				offset = (offset || 0) + this.offset;
+				return new BufferStream(self.buffer, offset, self.endPosition - offset, self.bigEndian);
+			},
+			offset: this.offset
+		};
+	},
+	offsetFrom: function(marker) {
+		return this.offset - marker.offset;
+	},
+	skip: function(amount) {
+		this.offset += amount;
+	},
+	branch: function(offset, length) {
+		length = typeof length === 'number' ? length : this.endPosition - (this.offset + offset);
+		return new BufferStream(this.buffer, this.offset + offset, length, this.bigEndian);
+	}
+};
+
+module.exports = BufferStream;