Function addNode

graphdb.js:236–327

(self, meta, callback)

}

function addNode(self, meta, callback) {

	// meta.typeid (1 CLASS, 2 RELATION)
	// meta.type (link to type class/relation)
	// meta.state
	// meta.parentindex
	// meta.relationindex
	// meta.size
	// meta.buffer

	var buf = U.createBufferSize(self.header.pagesize);
	var offset = offsetPage(self, meta.type.pageindex);

	meta.type.locked = true;

	Fs.read(self.fd, buf, 0, buf.length, offset, function(err) {

		if (err)
			throw err;

		if (buf[0] !== meta.typeid)
			throw new Error('Not a class page');

		if (!meta.type.private && buf[1] !== meta.type.index)
			throw new Error('Not same class type');

		// type          : buf[0]
		// index         : buf[1]
		// documents     : buf.readUInt16LE(2)
		// freeslots     : buf[4]
		// parentindex   : readUInt32LE(5)

		var buffer = U.createBufferSize(self.header.documentsize);
		buffer.writeUInt8(buf[0], 0);                      // type
		buffer.writeUInt8(meta.type.index, 1);             // index
		buffer.writeUInt32LE(meta.type.pageindex, 3);      // pageindex
		buffer.writeUInt8(meta.state || STATE_UNCOMPRESSED, 2);  // state
		buffer.writeUInt32LE(meta.relationindex || 0, 7);  // relationindex
		buffer.writeUInt32LE(meta.parentindex || 0, 11);   // parentindex
		buffer.writeUInt16LE(meta.size, 15);
		meta.data && meta.data.copy(buffer, DATAOFFSET);

		var documents = buf.readUInt16LE(2);
		var documentsbuf = U.createBufferSize(2);

		documents++;
		documentsbuf.writeUInt16LE(documents);

		Fs.write(self.fd, documentsbuf, 0, documentsbuf.length, offset + 2, function(err) {

			err && console.log('addNode.write.meta', err);
			Fs.write(self.fd, buffer, 0, buffer.length, offset + self.header.pagesize + ((documents - 1) * self.header.documentsize), function(err) {

				err && console.log('addNode.write.data', err);

				// type (1b)              = from: 0
				// index (1b)             = from: 1
				// state (1b)             = from: 2