/* NSC -- new Scala compiler
* Copyright 2005-2006 LAMP/EPFL
* @author Martin Odersky
*/
// $Id$
package scala.tools.nsc
import java.lang.{Thread, System, Runtime}
import java.lang.NumberFormatException
import java.io.{File, IOException, PrintWriter, FileOutputStream}
import java.io.{BufferedReader, FileReader}
import java.net._
object CompileSocket {
/** The prefix of the port identification file, which is followed
* by the port number.
*/
private val dirName = "scalac-compile-server-port"
private val isWin = System.getProperty("os.name") startsWith "Windows"
private val cmdName = if (isWin) "scala.bat" else "scala"
/** The vm-part of the command to start a new scala compile server */
private val vmCommand =
System.getProperty("scala.home") match {
case null => cmdName
case dirname =>
val trial = new File(new File(dirname, "bin"), cmdName)
if (trial.canRead)
trial.getPath
else
cmdName
}
/** The class name of the scala compile server */
private val serverClass = "scala.tools.nsc.CompileServer"
/** A regular expression for checking compiler output for errors */
val errorRegex = ".*errors? found.*"
/** A Pattern object for checking compiler output for errors */
val errorPattern = java.util.regex.Pattern.compile(errorRegex)
private def fatal(msg: String) = {
System.err.println(msg)
exit(1)
}
private def info(msg: String) =
if (CompileClient.verbose) System.out.println(msg)
/** The temporary directory in which the port identification file is stored */
private val tmpDir = {
val totry = List(
Pair("scala.home", List("var", "scala-devel")),
Pair("user.home", List("tmp")),
Pair("java.io.tmpdir", Nil))
/** Expand a property-extensions pair into a complete File object */
def expand(trial: Pair[String, List[String]]): Option[File] = {
val Pair(topdirProp, extensions) = trial
val topdir = System.getProperty(topdirProp)
if (topdir eq null)
return None
val fulldir =
extensions.foldLeft[File](new File(topdir))(
(dir,ext) => new File(dir, ext))
Some(fulldir)
}
/** Test if file f is a writable directory */
def isDirWritable(f: File): Boolean =
f.isDirectory && f.canWrite
val potentials =
for {
val trial <- totry
val expanded = expand(trial)
!expanded.isEmpty
isDirWritable(expanded.get)
}
yield expanded.get
if (potentials.isEmpty)
fatal("Could not find a directory for port files")
else {
val d = new File(potentials.head, dirName)
info("[Temp directory: " + d + "]")
d.mkdirs
d
}
}
/** 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
* the string must be either empty or start with a ' '.
*/
private def serverCommand(vmArgs: String): String =
vmCommand + vmArgs + " " + serverClass
/** Start a new server; returns true iff it succeeds */
private def startNewServer(vmArgs: String): unit = {
val cmd = serverCommand(vmArgs)
info("[Executed command: " + cmd + "]")
try {
Runtime.getRuntime().exec(cmd)
// val exitVal = proc.waitFor()
// info("[Exit value: " + exitVal + "]")
} catch {
case ex: IOException =>
fatal("cannot start server." +
"\ntried command: " + cmd)
}
}
/** The port identification file */
def portFile(port: int) = new File(tmpDir, port.toString())
/** Poll for a server port number; return -1 if none exists yet */
private def pollPort(): int = {
val hits = tmpDir.listFiles()
if (hits.length == 0) -1
else
try {
for (val i <- 1 until hits.length) hits(i).delete()
hits(0).getName.toInt
} catch {
case ex: NumberFormatException =>
fatal(ex.toString() +
"\nbad file in temp directory: " +
hits(0).getAbsolutePath() +
"\nplease remove the file and try again")
}
}
/** Get the port number to which a scala compile server is connected;
* If no server is running yet, create one
*/
def getPort(vmArgs: String): int = {
var attempts = 0
var port = pollPort()
if (port < 0)
startNewServer(vmArgs)
while (port < 0 && attempts < MaxAttempts) {
attempts = attempts + 1
Thread.sleep(sleepTime)
port = pollPort()
}
info("[Port number: " + port + "]")
if (port < 0)
fatal("Could not connect to server.")
port
}
/** Set the port number to which a scala compile server is connected */
def setPort(port: int): unit =
try {
val f = new PrintWriter(new FileOutputStream(portFile(port)))
f.println(new java.util.Random().nextInt.toString)
f.close()
} catch {
case ex: /*FileNotFound+Security*/Exception =>
fatal("Cannot create file: " +
portFile(port).getAbsolutePath() + "; exiting")
}
/** Delete the port number to which a scala compile server was connected */
def deletePort(port: int): unit = portFile(port).delete()
def getOrCreateSocket(vmArgs: String): Socket = {
val nAttempts = 9
def getsock(attempts: int): Socket =
if (attempts == 0)
fatal("Unable to establish connection to server; exiting")
else {
val port = getPort(vmArgs)
val hostName = InetAddress.getLocalHost().getHostName()
try {
new Socket(hostName, port)
} catch {
case e: /*IO+Security*/Exception =>
System.err.println(e)
System.err.println("...connection attempt to server at port " +
port + " failed; re-trying...")
if (attempts % 2 == 0) portFile(port).delete()
Thread.sleep(100)
val result = getsock(attempts - 1)
if (attempts == nAttempts)
System.err.println("...connection established at port " +
port + "...")
result
}
}
getsock(nAttempts)
}
def getSocket(serverAdr: String): Socket = {
val cpos = serverAdr indexOf ':'
if (cpos < 0)
fatal("Malformed server address: " + serverAdr + "; exiting")
else {
val hostName = serverAdr.substring(0, cpos)
val port = try {
serverAdr.substring(cpos+1).toInt
} catch {
case ex: Throwable =>
fatal("Malformed server address: " + serverAdr + "; exiting")
}
getSocket(hostName, port)
}
}
def getSocket(hostName: String, port: int): Socket =
try {
new Socket(hostName, port)
} catch {
case e: /*IO+Security*/Exception =>
fatal("Unable to establish connection to server " +
hostName + ":" + port + "; exiting")
}
def getPassword(port: int): String = {
val f = new BufferedReader(new FileReader(portFile(port)))
val result = f.readLine()
f.close()
result
}
}
