package plan9.lib; import java.lang.Integer;import java.util.Map;import java.util.HashMap;import java.util.StringTokenizer;import java.nio.channels.SocketChannel;import java.net.*; // Plan 9/Inferno Dial interface to make network connections// from styx-n-9p.googlecode.com (MIT licence) /** * Dial makes network connections, using a network-independent textual form of addressing services on hosts. * It is based on Plan 9's <i>dial</i>(2). The current implementation supports only TCP/IP, * but the same interface can support non-Internet protocols without change. * It encapsulates the translation of textual forms of host and service names into IP addresses and port numbers, * allowing network connections to be made with a single call. Unlike <code>new Socket(hostname, port)</code>, * which is also a single operation, Dial guarantees that it will try all addresses for a host, has an interface not limited to IP networking, and will translate * Plan 9 service names to port numbers. * <p> * It knows the correct port numbers for various Plan 9 services, such as <b>9fs</b>, <b>exportfs</b> and <b>ticket</b>. * <p> * Instead of raising exceptions, Dial returns an error value and makes the diagnostic available in a per-thread error string. * <p> * There is no constructor: Dial contains only static values and methods. * <p> * * For example, combining dial and netmkaddr to connect to a <b>9fs</b> service: * <pre> * ByteChannel fd = Dial.dial(Dial.netmkaddr(args[0], "net", "9fs"), null); * if(fd == null) * error(String.format("can't dial %s: %s", args[0], Dial.errstr()); * </pre> */public class Dial { private Dial(){} private static ThreadLocal<String> lasterror = new ThreadLocal<String>(); /** Return the per-thread error string: the diagnostic from the last failed operation */ public final static String errstr() { return lasterror.get(); } /** Set the per-thread error string to the string <i>s</i> */ public final static void werrstr(String s) { lasterror.set(s); } private static Map<String,Integer> portmap = new HashMap<String,Integer>(){{ put("tcp!9fs", 564); put("tcp!whoami", 565); put("tcp!guard", 566); put("tcp!ticket", 567); put("tcp!exportfs", 17007); put("tcp!rexexec", 17009); put("tcp!ncpu", 17010); put("tcp!cpu", 17013); put("tcp!venti", 17034); put("tcp!wiki", 17035); put("tcp!secstore", 5356); put("udp!dns", 53); put("tcp!dns", 53); put("tcp!styx", 6666); put("tcp!infsched", 6678); // owen }}; /** * Dial (make a network connection to) the given destination network address. * The address (or "dial string") has the form <i>net</i><b>!</b><i>host</i><b>!</b><i>service</i>, * where * <dl> * <dt><i>net</i><dd>is a network or protocol. Use <b>net</b> to represent any network on which the host is found. * Use <b>tcp</b> to force the use of TCP/IP. * <dt><i>host</i><dd>is a symbolic name (eg, host name or DNS name), or a network address in textual form (eg, an IP address such as 127.0.0.1). * <dt><i>service</i><dd>is a symbolic name for the desired service, for instance <b>telnet</b>, or a numeric port number. * It can be any name supported by UNIX's <i>getservbyname</i>. * </dl> * {@link Dial#netmkaddr} builds a dial string from its three components, adding defaults as required. * <p> * Dial tries each possible network address for a host (a host name might correspond to several network addresses), * until one succeeds, or all have failed. On success, dial returns a SocketChannel value giving a full-duplex * connection to the remote host. On an error, it returns null, setting the error string to the diagnostic. * * @param dest network address in the form <i>net</i><b>!</b><i>host</i><b>!</b><i>service</i>. * @param local leave null or "" to use any local port (other values reserved for future use) * @return a SocketChannel value representing a full-duplex connection to the remote host, or null on any error */ static public final SocketChannel dial(String dest, String local){ StringTokenizer flds = new StringTokenizer(dest, "!"); int n = flds.countTokens(); if(n < 3){ werrstr("invalid network address for dial: "+dest); return null; } String net = flds.nextToken(); String host = flds.nextToken(); String svc = flds.nextToken(); if(net.equals("net")) net = "tcp"; else if(!net.equals("tcp")){ // TO DO: "udp" werrstr("no network to host: "+dest); return null; } InetAddress[] addrs; try{ addrs = InetAddress.getAllByName(host); }catch(UnknownHostException e){ werrstr("unknown host: "+host); return null; } int port = portno(svc); if(port < 0){ Integer p = portmap.get(net+"!"+svc); if(p == null){ werrstr("can't translate service: "+svc); return null; } port = p.intValue(); } for(InetAddress ip : addrs){ try{ SocketChannel sc = SocketChannel.open(new InetSocketAddress(ip, port)); if(sc != null){ sc.socket().setTcpNoDelay(true); return sc; } }catch(java.io.IOException e){ werrstr(e.getMessage()); } } return null; } /** * Add default network and service components as required to an address in {@link Dial#dial}'s form. * The address has {@link Dial#dial}'s <i>net</i><b>!</b><i>host</i><b>!</b><i>service</i> form, * but if <i>net</i> and <i>svc</i> are missing (ie, the address is just a host name), netmkaddr * will add them, using the values of its {@code net} and {@code svc} parameters. If only the <i>service</i> * is missing, netmkaddr will add it, using {@code svc}. * @param addr an address in one of the forms net!host!svc, net!host, or simply host * @param net default network name to use if addr hasn't got one * @param svc default service name to use if addr hasn't got one * @return a complete dial string */ static public final String netmkaddr(String addr, String net, String svc){ StringTokenizer flds = new StringTokenizer(addr, "!"); int n = flds.countTokens(); if(n <= 1){ if(net == null) net = "net"; if(svc == null) return net+"!"+addr; return net+"!"+addr+"!"+svc; } if(svc != null && n < 2) return addr+"!"+svc; return addr; } static private int portno(String s){ int n = 0; for(int i = 0; i < s.length(); i++){ char c = s.charAt(i); if(!(c >= '0' && c <= '9')) return -1; n = n*10 + ((int)c-'0'); } return n; }}
package plan9.lib;
import java.lang.Integer;
import java.util.Map;
import java.util.HashMap;
import java.util.StringTokenizer;
import java.nio.channels.SocketChannel;
import java.net.*;
// Plan 9/Inferno Dial interface to make network connections
// from styx-n-9p.googlecode.com (MIT licence)
/**
* Dial makes network connections, using a network-independent textual form of addressing services on hosts.
* It is based on Plan 9's <i>dial</i>(2). The current implementation supports only TCP/IP,
* but the same interface can support non-Internet protocols without change.
* It encapsulates the translation of textual forms of host and service names into IP addresses and port numbers,
* allowing network connections to be made with a single call. Unlike <code>new Socket(hostname, port)</code>,
* which is also a single operation, Dial guarantees that it will try all addresses for a host, has an interface not limited to IP networking, and will translate
* Plan 9 service names to port numbers.
* <p>
* It knows the correct port numbers for various Plan 9 services, such as <b>9fs</b>, <b>exportfs</b> and <b>ticket</b>.
* <p>
* Instead of raising exceptions, Dial returns an error value and makes the diagnostic available in a per-thread error string.
* <p>
* There is no constructor: Dial contains only static values and methods.
* <p>
*
* For example, combining dial and netmkaddr to connect to a <b>9fs</b> service:
* <pre>
* ByteChannel fd = Dial.dial(Dial.netmkaddr(args[0], "net", "9fs"), null);
* if(fd == null)
* error(String.format("can't dial %s: %s", args[0], Dial.errstr());
* </pre>
*/
public class Dial {
private Dial(){}
private static ThreadLocal<String> lasterror = new ThreadLocal<String>();
/** Return the per-thread error string: the diagnostic from the last failed operation */
public final static String errstr() { return lasterror.get(); }
/** Set the per-thread error string to the string <i>s</i> */
public final static void werrstr(String s) { lasterror.set(s); }
private static Map<String,Integer> portmap = new HashMap<String,Integer>(){{
put("tcp!9fs", 564);
put("tcp!whoami", 565);
put("tcp!guard", 566);
put("tcp!ticket", 567);
put("tcp!exportfs", 17007);
put("tcp!rexexec", 17009);
put("tcp!ncpu", 17010);
put("tcp!cpu", 17013);
put("tcp!venti", 17034);
put("tcp!wiki", 17035);
put("tcp!secstore", 5356);
put("udp!dns", 53);
put("tcp!dns", 53);
put("tcp!styx", 6666);
put("tcp!infsched", 6678); // owen
}};
/**
* Dial (make a network connection to) the given destination network address.
* The address (or "dial string") has the form <i>net</i><b>!</b><i>host</i><b>!</b><i>service</i>,
* where
* <dl>
* <dt><i>net</i><dd>is a network or protocol. Use <b>net</b> to represent any network on which the host is found.
* Use <b>tcp</b> to force the use of TCP/IP.
* <dt><i>host</i><dd>is a symbolic name (eg, host name or DNS name), or a network address in textual form (eg, an IP address such as 127.0.0.1).
* <dt><i>service</i><dd>is a symbolic name for the desired service, for instance <b>telnet</b>, or a numeric port number.
* It can be any name supported by UNIX's <i>getservbyname</i>.
* </dl>
* {@link Dial#netmkaddr} builds a dial string from its three components, adding defaults as required.
* <p>
* Dial tries each possible network address for a host (a host name might correspond to several network addresses),
* until one succeeds, or all have failed. On success, dial returns a SocketChannel value giving a full-duplex
* connection to the remote host. On an error, it returns null, setting the error string to the diagnostic.
*
* @param dest network address in the form <i>net</i><b>!</b><i>host</i><b>!</b><i>service</i>.
* @param local leave null or "" to use any local port (other values reserved for future use)
* @return a SocketChannel value representing a full-duplex connection to the remote host, or null on any error
*/
static public final SocketChannel dial(String dest, String local){
StringTokenizer flds = new StringTokenizer(dest, "!");
int n = flds.countTokens();
if(n < 3){
werrstr("invalid network address for dial: "+dest);
return null;
}
String net = flds.nextToken();
String host = flds.nextToken();
String svc = flds.nextToken();
if(net.equals("net"))
net = "tcp";
else if(!net.equals("tcp")){ // TO DO: "udp"
werrstr("no network to host: "+dest);
return null;
}
InetAddress[] addrs;
try{
addrs = InetAddress.getAllByName(host);
}catch(UnknownHostException e){
werrstr("unknown host: "+host);
return null;
}
int port = portno(svc);
if(port < 0){
Integer p = portmap.get(net+"!"+svc);
if(p == null){
werrstr("can't translate service: "+svc);
return null;
}
port = p.intValue();
}
for(InetAddress ip : addrs){
try{
SocketChannel sc = SocketChannel.open(new InetSocketAddress(ip, port));
if(sc != null){
sc.socket().setTcpNoDelay(true);
return sc;
}
}catch(java.io.IOException e){
werrstr(e.getMessage());
}
}
return null;
}
/**
* Add default network and service components as required to an address in {@link Dial#dial}'s form.
* The address has {@link Dial#dial}'s <i>net</i><b>!</b><i>host</i><b>!</b><i>service</i> form,
* but if <i>net</i> and <i>svc</i> are missing (ie, the address is just a host name), netmkaddr
* will add them, using the values of its {@code net} and {@code svc} parameters. If only the <i>service</i>
* is missing, netmkaddr will add it, using {@code svc}.
* @param addr an address in one of the forms net!host!svc, net!host, or simply host
* @param net default network name to use if addr hasn't got one
* @param svc default service name to use if addr hasn't got one
* @return a complete dial string
*/
static public final String netmkaddr(String addr, String net, String svc){
StringTokenizer flds = new StringTokenizer(addr, "!");
int n = flds.countTokens();
if(n <= 1){
if(net == null)
net = "net";
if(svc == null)
return net+"!"+addr;
return net+"!"+addr+"!"+svc;
}
if(svc != null && n < 2)
return addr+"!"+svc;
return addr;
}
static private int portno(String s){
int n = 0;
for(int i = 0; i < s.length(); i++){
char c = s.charAt(i);
if(!(c >= '0' && c <= '9'))
return -1;
n = n*10 + ((int)c-'0');
}
return n;
}
}