Error checking for Stdio calls

runtime/bin/stdio_patch.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 @patch class _StdIOUtils {
   @patch static Stdin _getStdioInputStream() {
     switch (_getStdioHandleType(0)) {
       case _STDIO_HANDLE_TYPE_TERMINAL:
       case _STDIO_HANDLE_TYPE_PIPE:
       case _STDIO_HANDLE_TYPE_SOCKET:
@@ skipping 29 matching lines @@
       throw new FileSystemException(
           "Error retrieving socket type", "", result);
     }
     return result;
   }
 
   @patch static _getStdioHandleType(int fd) native "File_GetStdioHandleType";
 }
 
 @patch class Stdin {
-  @patch int readByteSync() native "Stdin_ReadByte";
+  @patch int readByteSync() {
+    var result = _readByte();
+    if (result is OSError) {
+      throw new StdinException("Error reading byte from stdin", result);
+    }
+    return result;
+  }
 
-  @patch bool get echoMode => _echoMode;
-  @patch void set echoMode(bool enabled) { _echoMode = enabled; }
+  @patch bool get echoMode {
+    var result = _echoMode();
+    if (result is OSError) {
+      throw new StdinException("Error getting terminal echo mode", result);
+    }
+    return result;
+  }
+  @patch void set echoMode(bool enabled) {
+    var result = _setEchoMode(enabled);
+    if (result is OSError) {
+      throw new StdinException("Error setting terminal echo mode", result);
+    }
+  }
 
-  @patch bool get lineMode => _lineMode;
-  @patch void set lineMode(bool enabled) { _lineMode = enabled; }
+  @patch bool get lineMode {
+    var result = _lineMode();
+    if (result is OSError) {
+      throw new StdinException("Error getting terminal line mode", result);
+    }
+    return result;
+  }
+  @patch void set lineMode(bool enabled) {
+    var result = _setLineMode(enabled);
+    if (result is OSError) {
+      throw new StdinException("Error setting terminal line mode", result);
+    }
+  }
 
-  static bool get _echoMode native "Stdin_GetEchoMode";
-  static void set _echoMode(bool enabled) native "Stdin_SetEchoMode";
-  static bool get _lineMode native "Stdin_GetLineMode";
-  static void set _lineMode(bool enabled) native "Stdin_SetLineMode";
+  static _echoMode() native "Stdin_GetEchoMode";
+  static _setEchoMode(bool enabled) native "Stdin_SetEchoMode";
+  static _lineMode() native "Stdin_GetLineMode";
+  static _setLineMode(bool enabled) native "Stdin_SetLineMode";
+  static _readByte() native "Stdin_ReadByte";
 }
 
 @patch class Stdout {
   @patch bool _hasTerminal(int fd) {
     try {
       _terminalSize(fd);
       return true;
     } catch (_) {
       return false;
     }
   }
 
   @patch int _terminalColumns(int fd) => _terminalSize(fd)[0];
   @patch int _terminalLines(int fd) => _terminalSize(fd)[1];
 
   static List _terminalSize(int fd) {
     var size = _getTerminalSize(fd);
     if (size is! List) {
       throw new StdoutException("Could not get terminal size", size);
     }
     return size;
   }
 
   static _getTerminalSize(int fd) native "Stdout_GetTerminalSize";
 }
 
 
 _getStdioHandle(_NativeSocket socket, int num) native "Socket_GetStdioHandle";
 _getSocketType(_NativeSocket nativeSocket) native "Socket_GetType";