/* NSC -- new Scala compiler
* Copyright 2005-2010 LAMP/EPFL
* @author Martin Odersky
*/
// $Id$
package scala.tools.nsc
import java.io.{ IOException, FileNotFoundException, PrintWriter, FileOutputStream }
import java.io.{ BufferedReader, FileReader }
import java.util.regex.Pattern
import java.net._
import java.security.SecureRandom
import io.{ File, Path, Process, Socket }
import scala.util.control.Exception.catching
import scala.tools.util.StringOps.splitWhere
/** This class manages sockets for the fsc offline compiler. */
class CompileSocket {
protected def compileClient: StandardCompileClient = CompileClient //todo: lazy val
/** The prefix of the port identification file, which is followed
* by the port number.
*/
protected def dirName = "scalac-compile-server-port" //todo: lazy val
protected def cmdName = Properties.cmdName //todo: lazy val
/** The vm part of the command to start a new scala compile server */
protected val vmCommand = Properties.scalaHome match {
case null => cmdName
case dirname =>
val trial = File(dirname) / "bin" / cmdName
if (trial.canRead) trial.path
else cmdName
}
/** The class name of the scala compile server */
protected val serverClass = "scala.tools.nsc.CompileServer"
/** A regular expression for checking compiler output for errors */
val errorRegex = ".*(errors? found|don't know|bad option).*"
/** A Pattern object for checking compiler output for errors */
val errorPattern = Pattern compile errorRegex
protected def error(msg: String) = System.err.println(msg)
protected def fatal(msg: String) = {
error(msg)
throw new Exception("fsc failure")
}
protected def info(msg: String) =
if (compileClient.verbose) System.out.println(msg)
/** A temporary directory to use */
val tmpDir = {
val udir = Option(Properties.userName) getOrElse "shared"
val f = (Path(Properties.tmpDir) / "scala-devel" / udir).createDirectory()
if (f.isDirectory && f.canWrite) {
info("[Temp directory: " + f + "]")
f
}
else fatal("Could not find a directory for temporary files")
}
/* A directory holding port identification files */
val portsDir = (tmpDir / dirName).createDirectory()
/** Maximum number of polls for an available port */
private val MaxAttempts = 100
/** Time (in ms) to sleep between two polls */
private val sleepTime = 20
/** The command which starts the compile server, given vm arguments.
*
* @param vmArgs the argument string to be passed to the java or scala command
*/
private def serverCommand(vmArgs: Seq[String]): Seq[String] =
Seq(vmCommand) ++ vmArgs ++ Seq(serverClass) filterNot (_ == "")
/** Start a new server; returns true iff it succeeds */
private def startNewServer(vmArgs: String) {
val cmd = serverCommand(vmArgs split " " toSeq)
info("[Executed command: %s]" format cmd)
try Process exec cmd catch {
case ex: IOException => fatal("Cannot start compilation daemon.\ntried command: %s" format cmd)
}
}
/** The port identification file */
def portFile(port: Int) = portsDir / File(port.toString)
/** Poll for a server port number; return -1 if none exists yet */
private def pollPort(): Int = portsDir.list match {
case it if !it.hasNext => -1
case it =>
val ret = it.next.name.toInt
it foreach (_.delete())
ret
}
/** Get the port number to which a scala compile server is connected;
* If no server is running yet, then create one.
*/
def getPort(vmArgs: String): Int = {
var attempts = 0
var port = pollPort()
if (port < 0)
startNewServer(vmArgs)
while (port < 0 && attempts < MaxAttempts) {
attempts += 1
Thread.sleep(sleepTime)
port = pollPort()
}
info("[Port number: " + port + "]")
if (port < 0)
fatal("Could not connect to compilation daemon.")
port
}
/** Set the port number to which a scala compile server is connected */
def setPort(port: Int) {
val file = portFile(port)
val secret = new SecureRandom().nextInt.toString
try file writeAll List(secret) catch {
case e @ (_: FileNotFoundException | _: SecurityException) =>
fatal("Cannot create file: %s".format(file.path))
}
}
/** Delete the port number to which a scala compile server was connected */
def deletePort(port: Int) = portFile(port).delete()
/** Get a socket connected to a daemon. If create is true, then
* create a new daemon if necessary. Returns None if the connection
* cannot be established.
*/
def getOrCreateSocket(vmArgs: String, create: Boolean = true): Option[Socket] = {
// try for 5 seconds
val retryDelay = 100
val maxAttempts = (5 * 1000) / retryDelay
def getsock(attempts: Int): Option[Socket] = attempts match {
case 0 => error("Unable to establish connection to compilation daemon") ; None
case num =>
val port = if (create) getPort(vmArgs) else pollPort()
if (port < 0) return None
Socket(InetAddress.getLocalHost(), port).either match {
case Right(socket) =>
info("[Connected to compilation daemon at port %d]" format port)
Some(socket)
case Left(err) =>
info(err.toString)
info("[Connecting to compilation daemon at port %d failed; re-trying...]" format port)
if (attempts % 2 == 0)
deletePort(port) // 50% chance to stop trying on this port
Thread sleep retryDelay // delay before retrying
getsock(attempts - 1)
}
}
getsock(maxAttempts)
}
// XXX way past time for this to be central
def parseInt(x: String): Option[Int] =
try { Some(x.toInt) }
catch { case _: NumberFormatException => None }
def getSocket(serverAdr: String): Socket = (
for ((name, portStr) <- splitWhere(serverAdr, _ == ':', true) ; port <- parseInt(portStr)) yield
getSocket(name, port)
) getOrElse fatal("Malformed server address: %s; exiting" format serverAdr)
def getSocket(hostName: String, port: Int): Socket =
Socket(hostName, port).opt getOrElse fatal("Unable to establish connection to server %s:%d; exiting".format(hostName, port))
def getPassword(port: Int): String = {
val ff = portFile(port)
val f = ff.bufferedReader()
// allow some time for the server to start up
def check = {
Thread sleep 100
ff.length
}
if (Iterator continually check take 50 find (_ > 0) isEmpty) {
ff.delete()
fatal("Unable to establish connection to server.")
}
val result = f.readLine()
f.close()
result
}
}
object CompileSocket extends CompileSocket