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This bundle wraps Pi4j (http://pi4j.com) that wraps the native code Wiring Pi (http://wiringpi.com). It wraps these libraries to make them OSGi friendly and allow them to work together with the OSGi enRoute IoT circuit library (osgi.enroute.iot.circuit). The bundle will first use Pi4J to detect on what hardware it runs. If it runs on an appropriate type, it will register a component that can be configured with Metatype. The Metatype defines a full blown configuration template for all the Pi's functions. The GPIO's are registered as components for the circuit. Regardless of the success of the configuration, this bundle will also register a GpioController service, which is the main Pi4J class.

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package aQute.lib.base64;

import java.io.*;
import java.util.regex.*;

/*
 * Base 64 converter.
 * 
 * TODO Implement string to byte[]
 */
public class Base64 {
	byte[]				data;

	static final String	alphabet	= "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
	static byte[]		values		= new byte[128];
	static Pattern BASE64_P = Pattern.compile("(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?");

	static {
		for (int i = 0; i < values.length; i++) {
			values[i] = -1;
		}
		// Create reverse index
		for (int i = 0; i < alphabet.length(); i++) {
			char c = alphabet.charAt(i);
			values[c] = (byte) i;
		}
	}

	public Base64(byte data[]) {
		this.data = data;
	}

	public final static byte[] decodeBase64(String string) {
		ByteArrayOutputStream bout = new ByteArrayOutputStream(string.length() * 2 / 3);
		StringReader rdr = new StringReader(string.trim());
		try {
			decode(rdr, bout);
		}
		catch (Exception e) {
			// cannot happen
		}
		return bout.toByteArray();
	}

	public final static void decode(Reader rdr, OutputStream out) throws Exception {
		int register = 0;
		int i = 0;
		int pads = 0;

		byte test[] = new byte[3];
		int c;
		while ((c = rdr.read()) >= 0) {

			if (c > 0x7F)
				throw new IllegalArgumentException("Invalid base64 character in " + rdr + ", character value > 128 ");

			int v = 0;
			if (c == '=') {
				pads++;
			} else {
				v = values[c];
				if (v < 0)
					throw new IllegalArgumentException("Invalid base64 character in " + rdr + ", " + c);
			}
			register <<= 6;
			register |= v;
			test[2] = (byte) (register & 0xFF);
			test[1] = (byte) ((register >> 8) & 0xFF);
			test[0] = (byte) ((register >> 16) & 0xFF);

			i++;

			if ((i % 4) == 0) {
				flush(out, register, pads);
				register = 0;
				pads = 0;
			}
		}
	}

	static private void flush(OutputStream out, int register, int pads) throws IOException {
		switch (pads) {
			case 0 :
				out.write(0xFF & (register >> 16));
				out.write(0xFF & (register >> 8));
				out.write(0xFF & (register >> 0));
				break;

			case 1 :
				out.write(0xFF & (register >> 16));
				out.write(0xFF & (register >> 8));
				break;

			case 2 :
				out.write(0xFF & (register >> 16));
		}
	}

	public Base64(String s) {
		data = decodeBase64(s);
	}

	@Override
	public String toString() {
		return encodeBase64(data);
	}

	public static String encodeBase64(byte data[]) {
		StringWriter sw = new StringWriter();
		ByteArrayInputStream bin = new ByteArrayInputStream(data);
		try {
			encode(bin, sw);
		}
		catch (IOException e) {
			// can't happen
		}
		return sw.toString();
	}

	public Object toData() {
		return data;
	}

	public static void encode(InputStream in, Appendable sb) throws IOException {
		// StringBuilder sb = new StringBuilder();
		int buf = 0;
		int bits = 0;
		int out = 0;

		while (true) {
			if (bits >= 6) {
				bits -= 6;
				int v = 0x3F & (buf >> bits);
				sb.append(alphabet.charAt(v));
				out++;
			} else {
				int c = in.read();
				if (c < 0)
					break;

				buf <<= 8;
				buf |= 0xFF & c;
				bits += 8;
			}
		}
		if (bits != 0) {// must be less than 7
			sb.append(alphabet.charAt(0x3F & (buf << (6 - bits))));
			out++;
		}
		int mod = 4 - (out % 4);
		if (mod != 4) {
			for (int i = 0; i < mod; i++)
				sb.append('=');
		}
	}

	public static boolean isBase64(String value) {
		return BASE64_P.matcher(value).matches();
	}

}