On Sat, 16 Jun 2018 14:50:40 +0200, Mark Kettenis wrote:
> To be honest, I find the whole idea of invoking an external program to
> clear the screen insane.
Linking with curses doesn't increase the size a huge amount since
we just need to query terminfo.
text data bss dec hex
529120 12584 57024 598728 922c8 /bin/ksh
595671 21904 57024 674599 a4b27 ./obj/ksh
- todd
Index: bin/ksh/Makefile
===================================================================
RCS file: /cvs/src/bin/ksh/Makefile,v
retrieving revision 1.38
diff -u -p -u -r1.38 Makefile
--- bin/ksh/Makefile 6 Jan 2018 16:28:58 -0000 1.38
+++ bin/ksh/Makefile 16 Jun 2018 22:00:32 -0000
@@ -1,6 +1,9 @@
# $OpenBSD: Makefile,v 1.38 2018/01/06 16:28:58 millert Exp $
PROG= ksh
+DPADD+= ${LIBCURSES}
+LDADD+= -lcurses
+
SRCS= alloc.c c_ksh.c c_sh.c c_test.c c_ulimit.c edit.c emacs.c eval.c \
exec.c expr.c history.c io.c jobs.c lex.c mail.c main.c \
misc.c path.c shf.c syn.c table.c trap.c tree.c tty.c var.c \
Index: bin/ksh/edit.c
===================================================================
RCS file: /cvs/src/bin/ksh/edit.c,v
retrieving revision 1.65
diff -u -p -u -r1.65 edit.c
--- bin/ksh/edit.c 9 Apr 2018 17:53:36 -0000 1.65
+++ bin/ksh/edit.c 16 Jun 2018 22:09:17 -0000
@@ -138,10 +138,10 @@ x_flush(void)
shf_flush(shl_out);
}
-void
+int
x_putc(int c)
{
- shf_putc(c, shl_out);
+ return shf_putc(c, shl_out);
}
void
Index: bin/ksh/edit.h
===================================================================
RCS file: /cvs/src/bin/ksh/edit.h,v
retrieving revision 1.11
diff -u -p -u -r1.11 edit.h
--- bin/ksh/edit.h 26 Jan 2016 17:39:31 -0000 1.11
+++ bin/ksh/edit.h 16 Jun 2018 22:09:27 -0000
@@ -37,7 +37,7 @@ extern X_chars edchars;
/* edit.c */
int x_getc(void);
void x_flush(void);
-void x_putc(int);
+int x_putc(int);
void x_puts(const char *);
bool x_mode(bool);
int promptlen(const char *, const char **);
Index: bin/ksh/emacs.c
===================================================================
RCS file: /cvs/src/bin/ksh/emacs.c,v
retrieving revision 1.84
diff -u -p -u -r1.84 emacs.c
--- bin/ksh/emacs.c 16 Jan 2018 17:17:18 -0000 1.84
+++ bin/ksh/emacs.c 16 Jun 2018 22:12:24 -0000
@@ -21,6 +21,10 @@
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#ifndef SMALL
+# include <term.h>
+# include <curses.h>
+#endif
#include "sh.h"
#include "edit.h"
@@ -28,6 +32,7 @@
static Area aedit;
#define AEDIT &aedit /* area for kill ring and macro defns */
+#undef CTRL
#define CTRL(x) ((x) == '?' ? 0x7F : (x) & 0x1F) /*
ASCII */
#define UNCTRL(x) ((x) == 0x7F ? '?' : (x) | 0x40) /*
ASCII */
@@ -146,6 +151,7 @@ static int isu8cont(unsigned char);
/* proto's for keybindings */
static int x_abort(int);
static int x_beg_hist(int);
+static int x_clear_screen(int);
static int x_comp_comm(int);
static int x_comp_file(int);
static int x_complete(int);
@@ -202,6 +208,7 @@ static int x_debug_info(int);
static const struct x_ftab x_ftab[] = {
{ x_abort, "abort", 0 },
{ x_beg_hist, "beginning-of-history", 0 },
+ { x_clear_screen, "clear-screen", 0 },
{ x_comp_comm, "complete-command", 0 },
{ x_comp_file, "complete-file", 0 },
{ x_complete, "complete", 0 },
@@ -1004,12 +1011,19 @@ x_draw_line(int c)
{
x_redraw(-1);
return KSTD;
+}
+static int
+x_clear_screen(int c)
+{
+ x_redraw(-2);
+ return KSTD;
}
-/* Redraw (part of) the line. If limit is < 0, the everything is redrawn
- * on a NEW line, otherwise limit is the screen column up to which needs
- * redrawing.
+/* Redraw (part of) the line.
+ * A non-negative limit is the screen column up to which needs
+ * redrawing. A limit of -1 redraws on a new line, while a limit
+ * of -2 (attempts to) clear the screen.
*/
static void
x_redraw(int limit)
@@ -1018,9 +1032,23 @@ x_redraw(int limit)
char *cp;
x_adj_ok = 0;
- if (limit == -1)
+ if (limit == -2) {
+ int ret = -1;
+#ifndef SMALL
+ char *str, *term = str_val(global("TERM"));
+ if (term && *term) {
+ setupterm(term, 1, NULL);
+ str = tigetstr("clear");
+ if (str != NULL && str != (char *)-1)
+ ret = tputs(str, 1, x_putc) == ERR;
+ }
+#endif
+ if (ret != 0)
+ x_e_putc('\n');
+ }
+ else if (limit == -1)
x_e_putc('\n');
- else
+ else if (limit >= 0)
x_e_putc('\r');
x_flush();
if (xbp == xbuf) {
Index: bin/ksh/ksh.1
===================================================================
RCS file: /cvs/src/bin/ksh/ksh.1,v
retrieving revision 1.200
diff -u -p -u -r1.200 ksh.1
--- bin/ksh/ksh.1 30 May 2018 21:20:52 -0000 1.200
+++ bin/ksh/ksh.1 16 Jun 2018 12:29:34 -0000
@@ -4690,6 +4690,10 @@ Moves the cursor to the beginning of the
Uppercase the first character in the next
.Ar n
words, leaving the cursor past the end of the last word.
+.It clear-screen:
+Attempts to clears the screen by invoking
+.Xr clear 1
+and redraws the prompt and current input line.
.It comment: ^[#
If the current line does not begin with a comment character, one is added at
the beginning of the line and the line is entered (as if return had been
