Implement POSIX Curses typeahead function.

distrib/sets/lists/comp/mi

@@ -1,4 +1,4 @@
-#	$NetBSD: mi,v 1.2086 2016/12/31 17:46:35 roy Exp $
+#	$NetBSD: mi,v 1.2087 2016/12/31 22:47:01 roy Exp $
 #
 # Note: don't delete entries from here - mark them as "obsolete" instead.
 ./etc/mtree/set.comp				comp-sys-root
@@ -9467,6 +9467,7 @@
 ./usr/share/man/cat3/ttyslot.0			comp-c-catman		.cat
 ./usr/share/man/cat3/ttyunlock.0		comp-c-catman		.cat
 ./usr/share/man/cat3/twalk.0			comp-c-catman		.cat
+./usr/share/man/cat3/typeahead.0		comp-c-catman		.cat
 ./usr/share/man/cat3/typeof.0			comp-c-catman		.cat
 ./usr/share/man/cat3/types.0			comp-c-catman		.cat
 ./usr/share/man/cat3/tzalloc.0			comp-c-catman		.cat
@@ -16736,6 +16737,7 @@
 ./usr/share/man/html3/ttyslot.html		comp-c-htmlman		html
 ./usr/share/man/html3/ttyunlock.html		comp-c-htmlman		html
 ./usr/share/man/html3/twalk.html		comp-c-htmlman		html
+./usr/share/man/html3/typeahead.html		comp-c-htmlman		html
 ./usr/share/man/html3/typeof.html		comp-c-htmlman		html
 ./usr/share/man/html3/types.html		comp-c-htmlman		html
 ./usr/share/man/html3/tzalloc.html		comp-c-htmlman		html
@@ -24068,6 +24070,7 @@
 ./usr/share/man/man3/ttyslot.3			comp-c-man		.man
 ./usr/share/man/man3/ttyunlock.3		comp-c-man		.man
 ./usr/share/man/man3/twalk.3			comp-c-man		.man
+./usr/share/man/man3/typeahead.3		comp-c-man		.man
 ./usr/share/man/man3/typeof.3			comp-c-man		.man
 ./usr/share/man/man3/types.3			comp-c-man		.man
 ./usr/share/man/man3/tzalloc.3			comp-c-man		.man

lib/libcurses/Makefile

@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.74 2016/12/31 17:46:35 roy Exp $
+#	$NetBSD: Makefile,v 1.75 2016/12/31 22:47:01 roy Exp $
 #	@(#)Makefile	8.2 (Berkeley) 1/2/94
 
 .include <bsd.own.mk>
@@ -149,7 +149,8 @@ MLINKS+= curses_addch.3 addch.3 curses_addchstr.3 addchnstr.3 \
 	 curses_color.3 start_color.3 curses_pad.3 subpad.3 \
 	 curses_window.3 subwin.3 curses_input.3 timeout.3 \
 	 curses_touch.3 touchline.3 curses_touch.3 touchoverlap.3 \
-	 curses_touch.3 touchwin.3 curses_print.3 unctrl.3 \
+	 curses_touch.3 touchwin.3 curses_tty.3 typeahead.3 \
+	 curses_print.3 unctrl.3 \
 	 curses_underscore.3 underend.3 curses_underscore.3 underscore.3 \
 	 curses_input.3 ungetch.3 curses_touch.3 untouchwin.3 \
 	 curses_default_colors.3 use_default_colors.3 \

lib/libcurses/curses.h

@@ -1,4 +1,4 @@
-/*	$NetBSD: curses.h,v 1.110 2016/12/31 17:46:35 roy Exp $	*/
+/*	$NetBSD: curses.h,v 1.111 2016/12/31 22:47:01 roy Exp $	*/
 
 /*
  * Copyright (c) 1981, 1993, 1994
@@ -750,6 +750,7 @@ attr_t	 term_attrs(void);
 int	 touchline(WINDOW *, int, int);
 int	 touchoverlap(WINDOW *, WINDOW *);
 int	 touchwin(WINDOW *);
+int	 typeahead(int);
 int	 ungetch(int);
 int	 untouchwin(WINDOW *);
 int	 use_default_colors(void);

lib/libcurses/curses_private.h

@@ -1,4 +1,4 @@
-/*	$NetBSD: curses_private.h,v 1.52 2016/12/30 22:38:38 roy Exp $	*/
+/*	$NetBSD: curses_private.h,v 1.53 2016/12/31 22:47:01 roy Exp $	*/
 
 /*-
  * Copyright (c) 1998-2000 Brett Lymn
@@ -253,6 +253,7 @@ struct __screen {
 	wchar_t *unget_list;
 	int unget_len, unget_pos;
 	int filtered;
+	int checkfd;
 #ifdef HAVE_WCHAR
 #define MB_LEN_MAX 8
 #define MAX_CBUF_SIZE MB_LEN_MAX

lib/libcurses/curses_tty.3

@@ -1,4 +1,4 @@
-.\"	$NetBSD: curses_tty.3,v 1.9 2016/12/29 23:50:59 wiz Exp $
+.\"	$NetBSD: curses_tty.3,v 1.10 2016/12/31 22:47:01 roy Exp $
 .\"
 .\" Copyright (c) 2002
 .\"	Brett Lymn (blymn@NetBSD.org, brett_lymn@yahoo.com.au)
@@ -30,7 +30,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"
-.Dd December 29, 2016
+.Dd December 31, 2016
 .Dt CURSES_TTY 3
 .Os
 .Sh NAME
@@ -65,6 +65,7 @@
 .Nm nocbreak ,
 .Nm raw ,
 .Nm noraw ,
+.Nm typeahead ,
 .Nm savetty ,
 .Nm resetty
 .Nd curses terminal manipulation routines
@@ -133,6 +134,8 @@
 .Ft int
 .Fn noraw "void"
 .Ft int
+.Fn typeahead "int filedes"
+.Ft int
 .Fn savetty "void"
 .Ft int
 .Fn resetty "void"
@@ -318,6 +321,33 @@ The
 function puts the terminal into Raw mode, no input character
 translation is done nor is signal character processing.
 .Pp
+The
+.Fn typeahead
+function controls the detection of typeahead during a refresh based on the
+value of
+.Va filedes :
+.Bl -bullet -compact
+.It
+If
+.Ar filedes
+is a valid file descriptor, typeahead is enabled during refresh;
+Curses periodically checks
+.Ar filedes
+for input and aborts the refresh if any character is available.
+(This is the initial setting and the typeahead file descriptor corresponds
+to the input file associated with the screen created by
+.Fn initscr
+or
+.Fn newterm .
+The value of
+.Ar filedes
+need not be the file descriptor on which the refresh is occurring.
+.It
+If
+.Ar filedes
+is \-1, Curses does not check for typeahead during refresh.
+.El
+.Pp
 The terminal
 tty flags can be saved by calling
 .Fn savetty

lib/libcurses/refresh.c

@@ -1,4 +1,4 @@
-/*	$NetBSD: refresh.c,v 1.80 2016/01/10 08:11:06 jdc Exp $	*/
+/*	$NetBSD: refresh.c,v 1.81 2016/12/31 22:47:01 roy Exp $	*/
 
 /*
  * Copyright (c) 1981, 1993, 1994
@@ -34,10 +34,11 @@
 #if 0
 static char sccsid[] = "@(#)refresh.c	8.7 (Berkeley) 8/13/94";
 #else
-__RCSID("$NetBSD: refresh.c,v 1.80 2016/01/10 08:11:06 jdc Exp $");
+__RCSID("$NetBSD: refresh.c,v 1.81 2016/12/31 22:47:01 roy Exp $");
 #endif
 #endif				/* not lint */
 
+#include <poll.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -586,6 +587,16 @@ doupdate(void)
 			quickch();
 	}
 
+	if (_cursesi_screen->checkfd != -1) {
+		struct pollfd fds[1];
+
+		/* If we have input, abort the update. */
+		fds[0].fd = _cursesi_screen->checkfd;
+		fds[0].events = POLLIN;
+		if (poll(fds, 1, 0) > 0)
+			goto cleanup;
+	}
+
 #ifdef DEBUG
 	{
 		int	i, j;
@@ -716,6 +727,7 @@ doupdate(void)
 		}
 	}
 
+cleanup:
 	/* Don't leave the screen with attributes set. */
 	__unsetattr(0);
 #ifdef DEBUG

lib/libcurses/screen.c

@@ -1,4 +1,4 @@
-/*	$NetBSD: screen.c,v 1.25 2016/12/30 22:38:38 roy Exp $	*/
+/*	$NetBSD: screen.c,v 1.26 2016/12/31 22:47:01 roy Exp $	*/
 
 /*
  * Copyright (c) 1981, 1993, 1994
@@ -34,7 +34,7 @@
 #if 0
 static char sccsid[] = "@(#)screen.c	8.2 (blymn) 11/27/2001";
 #else
-__RCSID("$NetBSD: screen.c,v 1.25 2016/12/30 22:38:38 roy Exp $");
+__RCSID("$NetBSD: screen.c,v 1.26 2016/12/31 22:47:01 roy Exp $");
 #endif
 #endif					/* not lint */
 
@@ -137,6 +137,7 @@ newterm(char *type, FILE *outfd, FILE *infd)
 #endif
 
 	new_screen->infd = infd;
+	new_screen->checkfd = fileno(infd);
 	new_screen->outfd = outfd;
 	new_screen->echoit = new_screen->nl = 1;
 	new_screen->pfast = new_screen->rawmode = new_screen->noqch = 0;

lib/libcurses/tty.c

@@ -1,4 +1,4 @@
-/*	$NetBSD: tty.c,v 1.44 2016/12/12 04:20:31 christos Exp $	*/
+/*	$NetBSD: tty.c,v 1.45 2016/12/31 22:47:01 roy Exp $	*/
 
 /*-
  * Copyright (c) 1992, 1993, 1994
@@ -34,7 +34,7 @@
 #if 0
 static char sccsid[] = "@(#)tty.c	8.6 (Berkeley) 1/10/95";
 #else
-__RCSID("$NetBSD: tty.c,v 1.44 2016/12/12 04:20:31 christos Exp $");
+__RCSID("$NetBSD: tty.c,v 1.45 2016/12/31 22:47:01 roy Exp $");
 #endif
 #endif				/* not lint */
 
@@ -670,3 +670,11 @@ killwchar( wchar_t *ch )
 	return OK;
 #endif /* HAVE_WCHAR */
 }
+
+int
+typeahead(int filedes)
+{
+
+	_cursesi_screen->checkfd = filedes;
+	return OK;
+}