grep-lock.patch

diff -aurN grep-3.1/lib/colorize-w32.c grep-3.1-fixed/lib/colorize-w32.c
--- grep-3.1/lib/colorize-w32.c	2017-01-01 03:34:33.000000000 -0800
+++ grep-3.1-fixed/lib/colorize-w32.c	2017-07-30 16:43:02.773225700 -0700
@@ -32,6 +32,27 @@
 
 static HANDLE hstdout = INVALID_HANDLE_VALUE;
 static SHORT norm_attr;
+static CRITICAL_SECTION color_lock;
+static BOOL color_bool = TRUE;
+
+/* After Ctrl+C or Ctrl+Break,
+   restore the normal text attribute used by the console.  */
+static BOOL WINAPI
+w32_color_handler (DWORD ctrl_type)
+{
+  if (ctrl_type == CTRL_C_EVENT
+      || ctrl_type == CTRL_BREAK_EVENT)
+    {
+      EnterCriticalSection (&color_lock);
+      if (hstdout != INVALID_HANDLE_VALUE)
+        {
+          SetConsoleTextAttribute (hstdout, norm_attr);
+        }
+      color_bool = FALSE;
+      LeaveCriticalSection (&color_lock);
+    }
+  return FALSE;
+}
 
 /* Initialize the normal text attribute used by the console.  */
 void
@@ -45,6 +66,9 @@
      norm_attr = csbi.wAttributes;
   else
     hstdout = INVALID_HANDLE_VALUE;
+
+  InitializeCriticalSectionAndSpinCount (&color_lock, 4000);
+  SetConsoleCtrlHandler (&w32_color_handler, TRUE);
 }
 
 /* Return non-zero if we should highlight matches in output.  */
@@ -164,7 +188,12 @@
   if (hstdout != INVALID_HANDLE_VALUE)
     {
       SHORT attr = w32_sgr2attr (sgr_seq);
-      SetConsoleTextAttribute (hstdout, attr);
+      EnterCriticalSection (&color_lock);
+      if (color_bool)
+        {
+          SetConsoleTextAttribute (hstdout, attr);
+        }
+      LeaveCriticalSection (&color_lock);
     }
   else
     printf (sgr_start, sgr_seq);