From ba47e60eeb3588ce04d91eb618934b0076db13ee Mon Sep 17 00:00:00 2001
From: Corey Johnson & Kevin Sawicki <cj+kevin@github.com>
Date: Tue, 26 Feb 2013 08:58:52 -0800
Subject: [PATCH] Synchronize reads of task's stdout/stderr

This ensures that all the available data on standard
out and standard error has been read before the terminate
handler calls the JavaScript callback.

Without this synchronization the command panel specs
occasionally fail.
---
 native/v8_extensions/native.mm | 54 +++++++++++++++++++---------------
 1 file changed, 31 insertions(+), 23 deletions(-)

diff --git a/native/v8_extensions/native.mm b/native/v8_extensions/native.mm
index 9ce163a30..6af7622fa 100644
--- a/native/v8_extensions/native.mm
+++ b/native/v8_extensions/native.mm
@@ -447,41 +447,49 @@ namespace v8_extensions {
 
         context->Exit();
 
-        stdout.fileHandleForReading.writeabilityHandler = nil;
-        stderr.fileHandleForReading.writeabilityHandler = nil;
+        stdout.fileHandleForReading.readabilityHandler = nil;
+        stderr.fileHandleForReading.readabilityHandler = nil;
       };
 
       task.terminationHandler = ^(NSTask *) {
-        NSString *output = [[NSString alloc] initWithData:[[stdout fileHandleForReading] readDataToEndOfFile] encoding:NSUTF8StringEncoding];
-        NSString *errorOutput  = [[NSString alloc] initWithData:[[stderr fileHandleForReading] readDataToEndOfFile] encoding:NSUTF8StringEncoding];
-        dispatch_sync(dispatch_get_main_queue(), ^() {
-          taskTerminatedHandle(output, errorOutput);
-        });
-        [output release];
-        [errorOutput release];
+        @synchronized(task) {
+          NSData *outputData = [[stdout fileHandleForReading] readDataToEndOfFile];
+          NSString *output = [[NSString alloc] initWithData:outputData encoding:NSUTF8StringEncoding];
+          NSData *errorData = [[stderr fileHandleForReading] readDataToEndOfFile];
+          NSString *errorOutput  = [[NSString alloc] initWithData:errorData encoding:NSUTF8StringEncoding];
+          dispatch_sync(dispatch_get_main_queue(), ^() {
+            taskTerminatedHandle(output, errorOutput);
+          });
+          [output release];
+          [errorOutput release];
+        }
       };
 
       CefRefPtr<CefV8Value> stdoutFunction = options->GetValue("stdout");
       if (stdoutFunction->IsFunction()) {
-        stdout.fileHandleForReading.writeabilityHandler = ^(NSFileHandle *fileHandle) {
-          NSData *data = [fileHandle availableData];
-          NSString *contents = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
-          dispatch_sync(dispatch_get_main_queue(), ^() {
-            outputHandle(contents, stdoutFunction);
-          });
-          [contents release];
+        stdout.fileHandleForReading.readabilityHandler = ^(NSFileHandle *fileHandle) {
+          @synchronized(task) {
+            NSData *data = [fileHandle availableData];
+            NSString *contents = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
+            dispatch_sync(dispatch_get_main_queue(), ^() {
+              outputHandle(contents, stdoutFunction);
+            });
+            [contents release];
+          }
         };
       }
 
       CefRefPtr<CefV8Value> stderrFunction = options->GetValue("stderr");
       if (stderrFunction->IsFunction()) {
-        stderr.fileHandleForReading.writeabilityHandler = ^(NSFileHandle *fileHandle) {
-          NSData *data = [fileHandle availableData];
-          NSString *contents = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
-          dispatch_sync(dispatch_get_main_queue(), ^() {
-            outputHandle(contents, stderrFunction);
-          });
-          [contents release];
+        stderr.fileHandleForReading.readabilityHandler = ^(NSFileHandle *fileHandle) {
+          @synchronized(task) {
+            NSData *data = [fileHandle availableData];
+            NSString *contents = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
+            dispatch_sync(dispatch_get_main_queue(), ^() {
+              outputHandle(contents, stderrFunction);
+            });
+            [contents release];
+          }
         };
       }