[dart:io][windows] Set Console VT modes

runtime/bin/platform_win.cc

Index: runtime/bin/platform_win.cc
diff --git a/runtime/bin/platform_win.cc b/runtime/bin/platform_win.cc
index 640f99b1b11c840c4ab1186fb917b213ae556222..85ce6b59094d28caaadb39128a743ad197df2a19 100644
--- a/runtime/bin/platform_win.cc
+++ b/runtime/bin/platform_win.cc
@@ -19,6 +19,12 @@
 #include "bin/utils.h"
 #include "bin/utils_win.h"
 
+// This is not always defined in the header files. See:
+// https://msdn.microsoft.com/en-us/library/windows/desktop/ms686033(v=vs.85).aspx
+#ifndef ENABLE_VIRTUAL_TERMINAL_INPUT
+#define ENABLE_VIRTUAL_TERMINAL_INPUT 0x200
+#endif
+
 namespace dart {
 
 // Defined in vm/os_thread_win.cc
@@ -49,24 +55,52 @@ class PlatformWin {
     SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOOPENFILEERRORBOX);
   }
 
-  static void SaveAndSetOutputCP() {
+  static void SaveAndConfigureConsole() {
     MutexLocker ml(platform_win_mutex_);
     ASSERT(saved_output_cp_ == -1);
     saved_output_cp_ = GetConsoleOutputCP();
     SetConsoleOutputCP(CP_UTF8);
+
+    HANDLE out = GetStdHandle(STD_OUTPUT_HANDLE);
+    if ((out != INVALID_HANDLE_VALUE) &&
+        GetConsoleMode(out, &saved_console_out_mode_)) {
+      const DWORD request =
+          saved_console_out_mode_ | ENABLE_VIRTUAL_TERMINAL_PROCESSING;
+      SetConsoleMode(out, request);
+    }
+
+    HANDLE in = GetStdHandle(STD_INPUT_HANDLE);
+    if ((in != INVALID_HANDLE_VALUE) &&
+        GetConsoleMode(in, &saved_console_in_mode_)) {
+      const DWORD request =
+          saved_console_in_mode_ | ENABLE_VIRTUAL_TERMINAL_INPUT;
+      SetConsoleMode(in, request);
+    }
   }
 
-  static void RestoreOutputCP() {
+  static void RestoreConsole() {
     MutexLocker ml(platform_win_mutex_);
     if (saved_output_cp_ != -1) {
       SetConsoleOutputCP(saved_output_cp_);
       saved_output_cp_ = -1;
     }
+    HANDLE out = GetStdHandle(STD_OUTPUT_HANDLE);
+    if (out != INVALID_HANDLE_VALUE) {
+      SetConsoleMode(out, saved_console_out_mode_);
+      saved_console_out_mode_ = 0;
+    }
+    HANDLE in = GetStdHandle(STD_INPUT_HANDLE);
+    if (in != INVALID_HANDLE_VALUE) {
+      SetConsoleMode(in, saved_console_in_mode_);
+      saved_console_in_mode_ = 0;
+    }
   }
 
  private:
   static Mutex* platform_win_mutex_;
   static int saved_output_cp_;
+  static DWORD saved_console_out_mode_;
+  static DWORD saved_console_in_mode_;
 
   static void InvalidParameterHandler(const wchar_t* expression,
                                       const wchar_t* function,
@@ -82,11 +116,13 @@ class PlatformWin {
 };
 
 int PlatformWin::saved_output_cp_ = -1;
+DWORD PlatformWin::saved_console_out_mode_ = 0;
+DWORD PlatformWin::saved_console_in_mode_ = 0;
 Mutex* PlatformWin::platform_win_mutex_ = NULL;
 
 bool Platform::Initialize() {
   PlatformWin::InitOnce();
-  PlatformWin::SaveAndSetOutputCP();
+  PlatformWin::SaveAndConfigureConsole();
   return true;
 }
 
@@ -183,7 +219,7 @@ void Platform::Exit(int exit_code) {
   // TODO(zra): Remove once VM shuts down cleanly.
   ::dart::private_flag_windows_run_tls_destructors = false;
   // Restore the console's output code page
-  PlatformWin::RestoreOutputCP();
+  PlatformWin::RestoreConsole();
   // On Windows we use ExitProcess so that threads can't clobber the exit_code.
   // See: https://code.google.com/p/nativeclient/issues/detail?id=2870
   ::ExitProcess(exit_code);