Use UTF-8 line drawing characters on UTF-8 terminals. Fixes some stupid

terminals (I'm looking at you, putty) which disable the vt100 ACS mode
switching sequences in UTF-8 mode.

Also on terminals without ACS at all, use ASCII equivalents where
obvious.

6 files changed, 137 insertions, 54 deletions

diff --git a/Makefile b/Makefile
index b70804f1..70f073da 100644
--- a/Makefile
+++ b/Makefile
@@ -35,7 +35,7 @@ SRCS=	attributes.c cfg.c client.c clock.c \
 	mode-key.c names.c options.c paste.c procname.c \
 	resize.c screen-redraw.c screen-write.c screen.c session.c status.c \
 	signal.c server-fn.c server.c server-client.c server-window.c \
-	tmux.c tty-keys.c tty-term.c tty.c utf8.c \
+	tmux.c tty-acs.c tty-keys.c tty-term.c tty.c utf8.c \
 	window-choose.c window-clock.c window-copy.c window.c \
 	xterm-keys.c xmalloc.c
 
diff --git a/screen-redraw.c b/screen-redraw.c
index bd3010cb..2024e675 100644
--- a/screen-redraw.c
+++ b/screen-redraw.c
@@ -41,6 +41,8 @@ void	screen_redraw_draw_number(struct client *, struct window_pane *);
 #define CELL_JOIN 11
 #define CELL_OUTSIDE 12
 
+#define CELL_BORDERS " xqlkmjwvtun~"
+
 /* Check if cell is on the border of a particular pane. */
 int
 screen_redraw_cell_border1(struct window_pane *wp, u_int px, u_int py)
@@ -173,8 +175,6 @@ screen_redraw_screen(struct client *c, int status_only, int borders_only)
 	struct grid_cell	 active_gc, other_gc;
 	u_int		 	 i, j, type;
 	int		 	 status, fg, bg;
-	const u_char		*base, *ptr;
-	u_char		       	 ch, border[20];
 
 	/* Get status line, er, status. */
 	if (c->message_string != NULL || c->prompt_string != NULL)
@@ -193,6 +193,7 @@ screen_redraw_screen(struct client *c, int status_only, int borders_only)
 	memcpy(&other_gc, &grid_default_cell, sizeof other_gc);
 	memcpy(&active_gc, &grid_default_cell, sizeof active_gc);
 	active_gc.data = other_gc.data = 'x'; /* not space */
+	active_gc.attr = other_gc.attr = GRID_ATTR_CHARSET;
 	fg = options_get_number(&c->session->options, "pane-border-fg");
 	colour_set_fg(&other_gc, fg);
 	bg = options_get_number(&c->session->options, "pane-border-bg");
@@ -203,16 +204,6 @@ screen_redraw_screen(struct client *c, int status_only, int borders_only)
 	colour_set_bg(&active_gc, bg);
 
 	/* Draw background and borders. */
-	strlcpy(border, " |-....--||+.", sizeof border);
-	if (tty_term_has(tty->term, TTYC_ACSC)) {
-		base = " xqlkmjwvtun~";
-		for (ptr = base; *ptr != '\0'; ptr++) {
-			if ((ch = tty_get_acs(tty, *ptr)) != '\0')
-				border[ptr - base] = ch;
-		}
-		other_gc.attr |= GRID_ATTR_CHARSET;
-		active_gc.attr |= GRID_ATTR_CHARSET;
-	}
 	for (j = 0; j < tty->sy - status; j++) {
 		if (status_only && j != tty->sy - 1)
 			continue;
@@ -225,7 +216,7 @@ screen_redraw_screen(struct client *c, int status_only, int borders_only)
 			else
 				tty_attributes(tty, &other_gc);
 			tty_cursor(tty, i, j);
-			tty_putc(tty, border[type]);
+			tty_putc(tty, CELL_BORDERS[type]);
 		}
 	}
 
diff --git a/tmux.h b/tmux.h
index 34274b50..257c0816 100644
--- a/tmux.h
+++ b/tmux.h
@@ -972,6 +972,8 @@ struct tty_term {
 	char		*name;
 	u_int		 references;
 
+	char		 acs[UCHAR_MAX + 1][2];
+
 	struct tty_code	 codes[NTTYCODE];
 
 #define TERM_256COLOURS 0x1
@@ -1009,8 +1011,6 @@ struct tty {
 
 	struct grid_cell cell;
 
-	u_char		 acs[UCHAR_MAX + 1];
-
 #define TTY_NOCURSOR 0x1
 #define TTY_FREEZE 0x2
 #define TTY_ESCAPE 0x4
@@ -1372,7 +1372,6 @@ void	environ_push(struct environ *);
 
 /* tty.c */
 void	tty_raw(struct tty *, const char *);
-u_char	tty_get_acs(struct tty *, u_char);
 void	tty_attributes(struct tty *, const struct grid_cell *);
 void	tty_reset(struct tty *);
 void	tty_region_pane(struct tty *, const struct tty_ctx *, u_int, u_int);
@@ -1426,6 +1425,9 @@ const char	*tty_term_string2(
 int		 tty_term_number(struct tty_term *, enum tty_code_code);
 int		 tty_term_flag(struct tty_term *, enum tty_code_code);
 
+/* tty-acs.c */
+const char	*tty_acs_get(struct tty *, u_char);
+
 /* tty-keys.c */
 void	tty_keys_init(struct tty *);
 void	tty_keys_free(struct tty *);
diff --git a/tty-acs.c b/tty-acs.c
new file mode 100644
index 00000000..297c51ac
--- /dev/null
+++ b/tty-acs.c
@@ -0,0 +1,97 @@
+/* $OpenBSD$ */
+
+/*
+ * Copyright (c) 2010 Nicholas Marriott <nicm@users.sourceforge.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+
+#include "tmux.h"
+
+int	tty_acs_cmp(const void *, const void *);
+
+/* Table mapping ACS entries to UTF-8. */
+struct tty_acs_entry {
+	u_char	 	 key;
+	const char	*string;
+};
+const struct tty_acs_entry tty_acs_table[] = {
+	{ '+', "\342\206\222" },
+	{ ',', "\342\206\220" },
+	{ '-', "\342\206\221" },
+	{ '.', "\342\206\223" },
+	{ '0', "\342\226\256" },
+	{ '`', "\342\227\206" },
+	{ 'a', "\342\226\222" },
+	{ 'f', "\302\260" },
+	{ 'g', "\302\261" },
+	{ 'h', "\342\226\222" },
+	{ 'i', "\342\230\203" },
+	{ 'j', "\342\224\230" },
+	{ 'k', "\342\224\220" },
+	{ 'l', "\342\224\214" },
+	{ 'm', "\342\224\224" },
+	{ 'n', "\342\224\274" },
+	{ 'o', "\342\216\272" },
+	{ 'p', "\342\216\273" },
+	{ 'q', "\342\224\200" },
+	{ 'r', "\342\216\274" },
+	{ 's', "\342\216\275" },
+	{ 't', "\342\224\234" },
+	{ 'u', "\342\224\244" },
+	{ 'v', "\342\224\264" },
+	{ 'w', "\342\224\254" },
+	{ 'x', "\342\224\202" },
+	{ 'y', "\342\211\244" },
+	{ 'z', "\342\211\245" },
+	{ '{', "\317\200" },
+	{ '|', "\342\211\240" },
+	{ '}', "\302\243" },
+	{ '~', "\302\267" }
+};
+
+int
+tty_acs_cmp(const void *key, const void *value)
+{
+	const struct tty_acs_entry	*entry = value;
+	u_char				 ch;
+
+	ch = *(u_char *) key;
+	return (ch - entry->key);
+}
+
+/* Retrieve ACS to output as a string. */
+const char *
+tty_acs_get(struct tty *tty, u_char ch)
+{
+	struct tty_acs_entry *entry;
+
+	/* If not a UTF-8 terminal, use the ACS set. */
+	if (!(tty->flags & TTY_UTF8)) {
+		if (tty->term->acs[ch][0] == '\0')
+			return (NULL);
+		return (&tty->term->acs[ch][0]);
+	}
+
+	/* Otherwise look up the UTF-8 translation. */
+	entry = bsearch(&ch,
+	    tty_acs_table, nitems(tty_acs_table), sizeof tty_acs_table[0],
+	    tty_acs_cmp);
+	if (entry == NULL)
+		return (NULL);
+	return (entry->string);
+}
diff --git a/tty-term.c b/tty-term.c
index 18858501..1566253d 100644
--- a/tty-term.c
+++ b/tty-term.c
@@ -302,6 +302,7 @@ tty_term_find(char *name, int fd, const char *overrides, char **cause)
 	u_int				 i;
 	int		 		 n, error;
 	char				*s;
+	const char                      *acs;
 
 	SLIST_FOREACH(term, &tty_terms, entry) {
 		if (strcmp(term->name, name) == 0) {
@@ -315,7 +316,7 @@ tty_term_find(char *name, int fd, const char *overrides, char **cause)
 	term->name = xstrdup(name);
 	term->references = 1;
 	term->flags = 0;
-	memset(&term->codes, 0, sizeof term->codes);
+	memset(term->codes, 0, sizeof term->codes);
 	SLIST_INSERT_HEAD(&tty_terms, term, entry);
 
 	/* Set up curses terminal. */
@@ -411,6 +412,15 @@ tty_term_find(char *name, int fd, const char *overrides, char **cause)
 	if (!tty_term_flag(term, TTYC_XENL))
 		term->flags |= TERM_EARLYWRAP;
 
+	/* Generate ACS table. If none is present, use nearest ASCII. */
+	memset(term->acs, 0, sizeof term->acs);
+	if (tty_term_has(term, TTYC_ACSC))
+		acs = tty_term_string(term, TTYC_ACSC);
+	else
+		acs = "a#j+k+l+m+n+o-p-q-r-s-t+u+v+w+x|y<z>~.";
+	for (; acs[0] != '\0' && acs[1] != '\0'; acs += 2)
+		term->acs[(u_char) acs[0]][0] = acs[1];
+
 	return (term);
 
 error:
diff --git a/tty.c b/tty.c
index bf0a48b0..642b9766 100644
--- a/tty.c
+++ b/tty.c
@@ -31,8 +31,6 @@
 void	tty_read_callback(struct bufferevent *, void *);
 void	tty_error_callback(struct bufferevent *, short, void *);
 
-void	tty_fill_acs(struct tty *);
-
 int	tty_try_256(struct tty *, u_char, const char *);
 int	tty_try_88(struct tty *, u_char, const char *);
 
@@ -48,6 +46,9 @@ void	tty_emulate_repeat(
 void	tty_cell(struct tty *,
 	    const struct grid_cell *, const struct grid_utf8 *);
 
+#define tty_use_acs(tty) \
+	(tty_term_has(tty, TTYC_ACSC) && !((tty)->flags & TTY_UTF8))
+
 void
 tty_init(struct tty *tty, int fd, char *term)
 {
@@ -143,8 +144,6 @@ tty_open(struct tty *tty, const char *overrides, char **cause)
 
 	tty_keys_init(tty);
 
-	tty_fill_acs(tty);
-
 	return (0);
 }
 
@@ -201,7 +200,8 @@ tty_start_tty(struct tty *tty)
 	memcpy(&tty->cell, &grid_default_cell, sizeof tty->cell);
 
 	tty_putcode(tty, TTYC_RMKX);
-	tty_putcode(tty, TTYC_ENACS);
+	if (tty_use_acs(tty))
+		tty_putcode(tty, TTYC_ENACS);
 	tty_putcode(tty, TTYC_CLEAR);
 
 	tty_putcode(tty, TTYC_CNORM);
@@ -242,7 +242,8 @@ tty_stop_tty(struct tty *tty)
 		return;
 
 	tty_raw(tty, tty_term_string2(tty->term, TTYC_CSR, 0, ws.ws_row - 1));
-	tty_raw(tty, tty_term_string(tty->term, TTYC_RMACS));
+	if (tty_use_acs(tty))
+		tty_raw(tty, tty_term_string(tty->term, TTYC_RMACS));
 	tty_raw(tty, tty_term_string(tty->term, TTYC_SGR0));
 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMKX));
 	tty_raw(tty, tty_term_string(tty->term, TTYC_CLEAR));
@@ -258,30 +259,6 @@ tty_stop_tty(struct tty *tty)
 }
 
 void
-tty_fill_acs(struct tty *tty)
-{
-	const char *ptr;
-
-	memset(tty->acs, 0, sizeof tty->acs);
-	if (!tty_term_has(tty->term, TTYC_ACSC))
-		return;
-
-	ptr = tty_term_string(tty->term, TTYC_ACSC);
-	if (strlen(ptr) % 2 != 0)
-		return;
-	for (; *ptr != '\0'; ptr += 2)
-		tty->acs[(u_char) ptr[0]] = ptr[1];
-}
-
-u_char
-tty_get_acs(struct tty *tty, u_char ch)
-{
-	if (tty->acs[ch] != '\0')
-		return (tty->acs[ch]);
-	return (ch);
-}
-
-void
 tty_close(struct tty *tty)
 {
 	if (tty->log_fd != -1) {
@@ -360,11 +337,17 @@ tty_puts(struct tty *tty, const char *s)
 void
 tty_putc(struct tty *tty, u_char ch)
 {
-	u_int	sx;
+	const char	*acs;
+	u_int		 sx;
 
-	if (tty->cell.attr & GRID_ATTR_CHARSET)
-		ch = tty_get_acs(tty, ch);
-	bufferevent_write(tty->event, &ch, 1);
+	if (tty->cell.attr & GRID_ATTR_CHARSET) {
+		acs = tty_acs_get(tty, ch);
+		if (acs != NULL)
+			bufferevent_write(tty->event, acs, strlen(acs));
+		else
+			bufferevent_write(tty->event, &ch, 1);
+	} else
+		bufferevent_write(tty->event, &ch, 1);
 
 	if (ch >= 0x20 && ch != 0x7f) {
 		sx = tty->sx;
@@ -997,7 +980,7 @@ tty_reset(struct tty *tty)
 	if (memcmp(gc, &grid_default_cell, sizeof *gc) == 0)
 		return;
 
-	if (tty_term_has(tty->term, TTYC_RMACS) && gc->attr & GRID_ATTR_CHARSET)
+	if ((gc->attr & GRID_ATTR_CHARSET) && tty_use_acs(tty))
 		tty_putcode(tty, TTYC_RMACS);
 	tty_putcode(tty, TTYC_SGR0);
 	memcpy(gc, &grid_default_cell, sizeof *gc);
@@ -1234,7 +1217,7 @@ tty_attributes(struct tty *tty, const struct grid_cell *gc)
 	}
 	if (changed & GRID_ATTR_HIDDEN)
 		tty_putcode(tty, TTYC_INVIS);
-	if (changed & GRID_ATTR_CHARSET)
+	if ((changed & GRID_ATTR_CHARSET) && tty_use_acs(tty))
 		tty_putcode(tty, TTYC_SMACS);
 }