Correct the sign of exit codes for the process library.

runtime/bin/process_impl.dart

Index: runtime/bin/process_impl.dart
diff --git a/runtime/bin/process_impl.dart b/runtime/bin/process_impl.dart
index da02ccb578e0922743b2f3bf77c98b88861f9acf..f7d3076cf8f214df47da59cd8e540897fa36fbb9 100644
--- a/runtime/bin/process_impl.dart
+++ b/runtime/bin/process_impl.dart
@@ -58,13 +58,15 @@ class _Process implements Process {
     // Setup an exit handler to handle internal cleanup and possible
     // callback when a process terminates.
     _exitHandler.dataHandler = () {
-        final int EXIT_DATA_SIZE = 8;
+        final int EXIT_DATA_SIZE = 12;
         List<int> exitDataBuffer = new List<int>(EXIT_DATA_SIZE);
         InputStream input = _exitHandler.inputStream;
         int exitDataRead = 0;
 
         int exitCode(List<int> ints) {
-          return ints[4] + (ints[5] << 8) + (ints[6] << 16) + (ints[7] << 24);
+          var code =
+              ints[4] + (ints[5] << 8) + (ints[6] << 16) + (ints[7] << 24);
+          return (ints[8] == 0) ? code : -code;

[Søren Gjesse, 2011/11/09 15:12:45]

Should we assert that ints[8] is either 0 or 1 and that ints[9], ints[10] and
ints[11] are zero?

Maybe refactor converting 4 bytes to an int into a separate method.

[Mads Ager (google), 2011/11/09 15:37:11]

Thanks! Done. I'm using that method to get the negative indication as well and I
assert that it is either 0 or 1.

         }
 
         int exitPid(List<int> ints) {