1 files changed, 49 insertions, 0 deletions
diff --git a/src/repl/scala/tools/nsc/interpreter/InteractiveReader.scala b/src/repl/scala/tools/nsc/interpreter/InteractiveReader.scala
new file mode 100644
index 0000000000..28ddf2939c
--- /dev/null
+++ b/src/repl/scala/tools/nsc/interpreter/InteractiveReader.scala
@@ -0,0 +1,49 @@
+/* NSC -- new Scala compiler
+ * Copyright 2005-2013 LAMP/EPFL
+ * @author Stepan Koltsov
+ */
+
+package scala.tools.nsc
+package interpreter
+
+import java.io.IOException
+import session.History
+import InteractiveReader._
+import Properties.isMac
+
+/** Reads lines from an input stream */
+trait InteractiveReader {
+  val interactive: Boolean
+
+  def reset(): Unit
+  def history: History
+  def completion: Completion
+  def redrawLine(): Unit
+
+  def readYesOrNo(prompt: String, alt: => Boolean): Boolean = readOneKey(prompt) match {
+    case 'y'  => true
+    case 'n'  => false
+    case _    => alt
+  }
+
+  protected def readOneLine(prompt: String): String
+  protected def readOneKey(prompt: String): Int
+
+  def readLine(prompt: String): String =
+    // hack necessary for OSX jvm suspension because read calls are not restarted after SIGTSTP
+    if (isMac) restartSysCalls(readOneLine(prompt), reset())
+    else readOneLine(prompt)
+}
+
+object InteractiveReader {
+  val msgEINTR = "Interrupted system call"
+  def restartSysCalls[R](body: => R, reset: => Unit): R =
+    try body catch {
+      case e: IOException if e.getMessage == msgEINTR => reset ; body
+    }
+
+  def apply(): InteractiveReader = SimpleReader()
+  @deprecated("Use `apply` instead.", "2.9.0")
+  def createDefault(): InteractiveReader = apply() // used by sbt
+}
+