Add hidden key handler window

After BUG#6 had apparently been closed with the screen locks introduced
in commit a80f8dcf2c6eb3b54658218bc081ee9694204dd5, some people still
had problems with random characters appearing in the notification bar.
This was obviously caused by wgetch() refreshing the screen if the
status panel was changed. From wgetch(3):

    If the window is not a pad, and it has been moved or modified since
    the last call to wrefresh, wrefresh will be called before another
    character is read.

Since the wgetch(3) isn't thread-safe, there were race conditions
between the notification bar thread drawing to the notification bar and
wgetch() updating the screen. Introduce a (hidden) window that handles
all key presses and never gets changed in order to avoid this.

Also, call wins_wrefresh() explicitly in status_mesg(), since we can no
longer rely on wgetch() updating windows automatically.

Fixes reopened BUG#6. Note that this is a hotfix -- FR#26 has been
opened to ensure we fix this properly in the next major release.

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

1 files changed, 6 insertions, 1 deletions

diff --git a/src/calcurse.c b/src/calcurse.c
index c55db55..85a7941 100644
--- a/src/calcurse.c
+++ b/src/calcurse.c
@@ -565,6 +565,11 @@ int main(int argc, char **argv)
   io_load_todo();
   io_load_app();
   wins_reinit();
+  /*
+   * Refresh the hidden key handler window here to prevent wgetch() from
+   * implicitly calling wrefresh() later (causing ncurses race conditions).
+   */
+  wins_wrefresh(win[KEY].p);
   if (conf.system_dialogs) {
     wins_update(FLAG_ALL);
     io_startup_screen(no_data_file);
@@ -589,7 +594,7 @@ int main(int argc, char **argv)
       wins_reset();
     }
 
-    key = keys_getch(win[STA].p, &count, &reg);
+    key = keys_getch(win[KEY].p, &count, &reg);
     switch (key) {
     case KEY_GENERIC_REDRAW:
       resize = 1;