win32: only change console mode if necessary

In skip_ansi_emulation() only call SetConsoleMode() if the new
mode differs from the current mode.

1 files changed, 10 insertions, 7 deletions

diff --git a/win32/winansi.c b/win32/winansi.c
index 9db11cddb..27559e3f5 100644
--- a/win32/winansi.c
+++ b/win32/winansi.c
@@ -84,16 +84,19 @@ int skip_ansi_emulation(int reset)
 
                 if (is_console(STDOUT_FILENO)) {
                         HANDLE h = get_console();
-                        DWORD mode;
+                        DWORD oldmode, newmode;
 
-                        if (GetConsoleMode(h, &mode)) {
+                        if (GetConsoleMode(h, &oldmode)) {
+                                newmode = oldmode;
                                 if (skip)
-                                        mode |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
+                                        newmode |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
                                 else
-                                        mode &= ~ENABLE_VIRTUAL_TERMINAL_PROCESSING;
-                                mode &= ~DISABLE_NEWLINE_AUTO_RETURN;
-                                if (!SetConsoleMode(h, mode) && skip == 2)
-                                        skip = 0;
+                                        newmode &= ~ENABLE_VIRTUAL_TERMINAL_PROCESSING;
+                                newmode &= ~DISABLE_NEWLINE_AUTO_RETURN;
+                                if (newmode != oldmode) {
+                                        if (!SetConsoleMode(h, newmode) && skip == 2)
+                                                skip = 0;
+                                }
                         }
                 }
         }