Install some basic error handling in Dispatch.

[jrw.git] / src / jrw / FormData.java

package jrw;

import jrw.util.*;
import java.util.*;
import java.util.function.*;
import java.io.*;
import java.nio.*;
import java.nio.channels.*;

public class FormData extends HashMap<String, String> {
    public static final int MAX_LENGTH = 1 << 20;

    private static int htoi(byte hex) {
	if((hex >= '0') && (hex <= '9'))
	    return(hex - '0');
	if((hex >= 'A') && (hex <= 'F'))
	    return(hex - 'A' + 10);
	if((hex >= 'a') && (hex <= 'f'))
	    return(hex - 'a' + 10);
	return(0);
    }

    private static ByteBuffer unquoteb(ByteBuffer part) {
	ByteBuffer ret = ByteBuffer.allocate(part.remaining());
	while(part.remaining() > 0) {
	    int b = part.get() & 0xff;
	    if((b == '%') && (part.remaining() >= 2)) {
		int n1 = htoi(part.get()), n2 = htoi(part.get());
		ret.put((byte)((n1 << 4) | n2));
	    } else {
		ret.put((byte)b);
	    }
	}
	ret.flip();
	return(ret);
    }

    private static String unquote(ByteBuffer part) {
	ByteBuffer dec = unquoteb(part);
	try {
	    return(Http.UTF8.newDecoder().decode(dec.duplicate()).toString());
	} catch(java.nio.charset.CharacterCodingException e) {
	    return(Http.LATIN1.decode(dec).toString());
	}
    }

    private static String unquote(String part) {
	if(part.indexOf('%') < 0)
	    return(part);
	return(unquote(Http.UTF8.encode(CharBuffer.wrap(part))));
    }

    public static void parse(Map<? super String, ? super String> buf, ByteBuffer data) {
	int p = data.position(), p2, p3;
	while(p < data.limit()) {
	    for(p2 = p; (p2 < data.limit()) && (data.get(p2) != '&'); p2++);
	    for(p3 = p; (p3 < p2) && (data.get(p3) != '='); p3++);
	    if(p3 < p2) {
		buf.put(unquote((ByteBuffer)data.duplicate().position(p).limit(p3)),
			unquote((ByteBuffer)data.duplicate().position(p3 + 1).limit(p2)));
	    }
	    p = p2 + 1;
	}
    }

    public static void parse(Map<? super String, ? super String> buf, String data) {
	int p = 0;
	while(true) {
	    int p2 = data.indexOf('&', p);
	    String part = (p2 < 0) ? data.substring(p) : data.substring(p, p2);
	    int p3 = part.indexOf('=');
	    if(p3 >= 0)
		buf.put(unquote(part.substring(0, p3)), unquote(part.substring(p3 + 1)));
	    if(p2 < 0)
		break;
	    p = p2 + 1;
	}
    }

    public static FormData read(Request req) {
	FormData ret = new FormData();
	String query = (String)req.env.get("QUERY_STRING");
	if(query != null)
	    parse(ret, query);
	if(req.ihead("Content-Type", "").equals("application/x-www-form-urlencoded")) {
	    int max = MAX_LENGTH;
	    String clen = req.ihead("Content-Length", null);
	    if(clen != null) {
		try {
		    max = Math.min(max, Integer.parseInt(clen));
		} catch(NumberFormatException e) {
		}
	    }
	    ReadableByteChannel in = (ReadableByteChannel)req.env.get("jagi.input");
	    if(in instanceof SelectableChannel) {
		try {
		    ((SelectableChannel)in).configureBlocking(true);
		} catch(IOException e) {
		}
	    }
	    ByteBuffer buf = ByteBuffer.allocate(65536);
	    while(buf.position() < max) {
		if(buf.remaining() == 0) {
		    ByteBuffer n = ByteBuffer.allocate(Math.min(buf.capacity() * 2, max));
		    buf.flip();
		    n.put(buf);
		    buf = n;
		}
		try {
		    int rv = in.read(buf);
		    if(rv <= 0)
			break;
		} catch(IOException e) {
		    break;
		}
	    }
	    buf.flip();
	    parse(ret, buf);
	}
	return(ret);
    }

    public static FormData get(Request req) {
	FormData ret = (FormData)req.env.get(FormData.class);
	if(ret == null)
	    req.env.put(FormData.class, ret = read(req));
	return(ret);
    }

    static class Collector extends ByteArrayOutputStream {
	final FormData form = new FormData();
	final Request req;

	Collector(Request req) {
	    this.req = req;
	    req.env.put(FormData.class, this.form);
	    String query = (String)req.env.get("QUERY_STRING");
	    if(query != null)
		parse(form, query);
	}

	public void write(int b) {
	    if(count < MAX_LENGTH)
		super.write(b);
	}

	public void write(byte[] buf, int off, int len) {
	    len = Math.min(len, MAX_LENGTH - count);
	    if(len > 0)
		super.write(buf, off, len);
	}

	public void close() {
	    parse(form, ByteBuffer.wrap(toByteArray()));
	}
    }

    public static Map<Object, Object> feed(Request req, Handler next) {
	Map<Object, Object> resp = new HashMap<>();
	if(req.ihead("Content-Type", "").equals("application/x-www-form-urlencoded")) {
	    resp.put("jagi.status", "feed-input");
	    resp.put("jagi.next", (Function<Map<Object, Object>, Map<Object, Object>>)env -> Dispatch.handle(next, req));
	    resp.put("jagi.input-sink", new Collector(req));
	} else {
	    read(req);
	    resp.put("jagi.status", "chain");
	    resp.put("jagi.next", (Function<Map<Object, Object>, Map<Object, Object>>)env -> Dispatch.handle(next, req));
	}
	return(resp);
    }
}