fix terminal resizing (SIGWINCH)

When I replaced ncmpc's old main loop with g_main_loop from libglib,
SIGWINCH (i.e. window resizing) stopped working.  This regression was
caused by the fact that ncurses' wgetch() function was only called
when there was actually data on STDIN.  wgetch() has several side
effects besides reading data from STDIN, for example it checks whether
there has been a window resize.

Fix this with a custom SIGWINCH handler.

1 files changed, 33 insertions, 0 deletions

diff --git a/src/main.c b/src/main.c
index c8b22df5f..6f662f53c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -150,6 +150,31 @@ sigstop(void)
   kill(0, SIGSTOP); /* issue SIGSTOP */
 }
 
+static guint timer_sigwinch_id;
+
+static gboolean
+timer_sigwinch(mpd_unused gpointer data)
+{
+	/* the following causes the screen to flicker.  There might be
+	   better solutions, but I believe it isn't all that
+	   important. */
+
+	endwin();
+	refresh();
+	screen_resize();
+
+	return FALSE;
+}
+
+static void
+catch_sigwinch(mpd_unused int sig)
+{
+	if (timer_sigwinch_id != 0)
+		g_source_remove(timer_sigwinch_id);
+
+	timer_sigwinch_id = g_timeout_add(100, timer_sigwinch, NULL);
+}
+
 #ifndef NDEBUG
 void 
 D(const char *format, ...)
@@ -383,6 +408,14 @@ main(int argc, const char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
+	/* setup SIGWINCH */
+
+	act.sa_handler = catch_sigwinch;
+	if (sigaction(SIGWINCH, &act, NULL) < 0) {
+		perror("sigaction(SIGWINCH)");
+		exit(EXIT_FAILURE);
+	}
+
 	ncurses_init();
 
 	lyrics_init();