Support colouring of WriteStatusLog messages

If the prefix string includes ERROR or WARNING these messages
are now shown in colour (red or yellow) similar to how log lines
are displayed.

Signed-off-by: Selva Nair <selva.nair@gmail.com>

openvpn.c

@@ -1528,6 +1528,29 @@ WriteStatusLog (connection_t *c, const WCHAR *prefix, const WCHAR *line, BOOL fi
     wcsncpy (datetime, _wctime(&now), _countof(datetime));
     datetime[24] = L' ';
 
+    /* change text color if Warning or Error */
+    COLORREF text_clr = 0;
+
+    if (wcsstr(prefix, L"ERROR"))
+    {
+        text_clr = o.clr_error;
+    }
+    else if (wcsstr(prefix, L"WARNING"))
+    {
+        text_clr = o.clr_warning;
+    }
+
+    if (text_clr != 0)
+    {
+        CHARFORMAT cfm = { .cbSize = sizeof(CHARFORMAT),
+                           .dwMask = CFM_COLOR|CFM_BOLD,
+                           .dwEffects = 0,
+                           .crTextColor = text_clr,
+                         };
+        SendMessage(logWnd, EM_SETCHARFORMAT, SCF_SELECTION, (LPARAM) &cfm);
+    }
+
+
     /* Remove lines from log window if it is getting full */
     if (SendMessage(logWnd, EM_GETLINECOUNT, 0, 0) > MAX_LOG_LINES)
     {