===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/tty.c,v
retrieving revision 1.393
retrieving revision 1.394
diff -u -r1.393 -r1.394
--- src/usr.bin/tmux/tty.c	2021/06/10 07:59:31	1.393
+++ src/usr.bin/tmux/tty.c	2021/08/05 09:43:51	1.394
@@ -1,4 +1,4 @@
-/* $OpenBSD: tty.c,v 1.393 2021/06/10 07:59:31 nicm Exp $ */
+/* $OpenBSD: tty.c,v 1.394 2021/08/05 09:43:51 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -67,6 +67,7 @@
 static void	tty_draw_pane(struct tty *, const struct tty_ctx *, u_int);
 static void	tty_default_attributes(struct tty *, const struct grid_cell *,
 		    int *, u_int);
+static int	tty_check_overlay(struct tty *, u_int, u_int);
 
 #define tty_use_margin(tty) \
 	(tty->term->flags & TERM_DECSLRM)
@@ -1069,6 +1070,7 @@
     u_int px, u_int nx, u_int bg)
 {
 	struct client	*c = tty->client;
+	u_int		 i;
 
 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
 
@@ -1077,7 +1079,7 @@
 		return;
 
 	/* If genuine BCE is available, can try escape sequences. */
-	if (!tty_fake_bce(tty, defaults, bg)) {
+	if (c->overlay_check == NULL && !tty_fake_bce(tty, defaults, bg)) {
 		/* Off the end of the line, use EL if available. */
 		if (px + nx >= tty->sx && tty_term_has(tty->term, TTYC_EL)) {
 			tty_cursor(tty, px, py);
@@ -1100,9 +1102,22 @@
 		}
 	}
 
-	/* Couldn't use an escape sequence, use spaces. */
+	/*
+	 * Couldn't use an escape sequence, use spaces. Clear only the visible
+	 * bit if there is an overlay.
+	 */
+	for (i = 0; i < nx; i++) {
+		if (!tty_check_overlay(tty, px + i, py))
+			break;
+	}
 	tty_cursor(tty, px, py);
-	tty_repeat_space(tty, nx);
+	tty_repeat_space(tty, i);
+	for (; i < nx; i++) {
+		if (tty_check_overlay(tty, px + i, py))
+			break;
+	}
+	tty_cursor(tty, px + i, py);
+	tty_repeat_space(tty, nx - i);
 }
 
 /* Clear a line, adjusting to visible part of pane. */
@@ -1197,7 +1212,7 @@
 		return;
 
 	/* If genuine BCE is available, can try escape sequences. */
-	if (!tty_fake_bce(tty, defaults, bg)) {
+	if (c->overlay_check == NULL && !tty_fake_bce(tty, defaults, bg)) {
 		/* Use ED if clearing off the bottom of the terminal. */
 		if (px == 0 &&
 		    px + nx >= tty->sx &&
@@ -1332,6 +1347,7 @@
 	struct grid_cell	 gc, last;
 	const struct grid_cell	*gcp;
 	struct grid_line	*gl;
+	struct client		*c = tty->client;
 	u_int			 i, j, ux, sx, width;
 	int			 flags, cleared = 0, wrapped = 0;
 	char			 buf[512];
@@ -1383,7 +1399,8 @@
 		    atx == 0 &&
 		    px + sx != nx &&
 		    tty_term_has(tty->term, TTYC_EL1) &&
-		    !tty_fake_bce(tty, defaults, 8)) {
+		    !tty_fake_bce(tty, defaults, 8) &&
+		    c->overlay_check == NULL) {
 			tty_default_attributes(tty, defaults, palette, 8);
 			tty_cursor(tty, nx - 1, aty);
 			tty_putcode(tty, TTYC_EL1);
@@ -1547,11 +1564,14 @@
 void
 tty_cmd_insertcharacter(struct tty *tty, const struct tty_ctx *ctx)
 {
+	struct client	*c = tty->client;
+
 	if (ctx->bigger ||
 	    !tty_full_width(tty, ctx) ||
 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
 	    (!tty_term_has(tty->term, TTYC_ICH) &&
-	    !tty_term_has(tty->term, TTYC_ICH1))) {
+	    !tty_term_has(tty->term, TTYC_ICH1)) ||
+	    c->overlay_check != NULL) {
 		tty_draw_pane(tty, ctx, ctx->ocy);
 		return;
 	}
@@ -1566,11 +1586,14 @@
 void
 tty_cmd_deletecharacter(struct tty *tty, const struct tty_ctx *ctx)
 {
+	struct client	*c = tty->client;
+
 	if (ctx->bigger ||
 	    !tty_full_width(tty, ctx) ||
 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
 	    (!tty_term_has(tty->term, TTYC_DCH) &&
-	    !tty_term_has(tty->term, TTYC_DCH1))) {
+	    !tty_term_has(tty->term, TTYC_DCH1)) ||
+	    c->overlay_check != NULL) {
 		tty_draw_pane(tty, ctx, ctx->ocy);
 		return;
 	}
@@ -1593,13 +1616,16 @@
 void
 tty_cmd_insertline(struct tty *tty, const struct tty_ctx *ctx)
 {
+	struct client	*c = tty->client;
+
 	if (ctx->bigger ||
 	    !tty_full_width(tty, ctx) ||
 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
 	    !tty_term_has(tty->term, TTYC_CSR) ||
 	    !tty_term_has(tty->term, TTYC_IL1) ||
 	    ctx->sx == 1 ||
-	    ctx->sy == 1) {
+	    ctx->sy == 1 ||
+	    c->overlay_check != NULL) {
 		tty_redraw_region(tty, ctx);
 		return;
 	}
@@ -1617,13 +1643,16 @@
 void
 tty_cmd_deleteline(struct tty *tty, const struct tty_ctx *ctx)
 {
+	struct client	*c = tty->client;
+
 	if (ctx->bigger ||
 	    !tty_full_width(tty, ctx) ||
 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
 	    !tty_term_has(tty->term, TTYC_CSR) ||
 	    !tty_term_has(tty->term, TTYC_DL1) ||
 	    ctx->sx == 1 ||
-	    ctx->sy == 1) {
+	    ctx->sy == 1 ||
+	    c->overlay_check != NULL) {
 		tty_redraw_region(tty, ctx);
 		return;
 	}
@@ -1667,6 +1696,8 @@
 void
 tty_cmd_reverseindex(struct tty *tty, const struct tty_ctx *ctx)
 {
+	struct client	*c = tty->client;
+
 	if (ctx->ocy != ctx->orupper)
 		return;
 
@@ -1677,7 +1708,8 @@
 	    (!tty_term_has(tty->term, TTYC_RI) &&
 	    !tty_term_has(tty->term, TTYC_RIN)) ||
 	    ctx->sx == 1 ||
-	    ctx->sy == 1) {
+	    ctx->sy == 1 ||
+	    c->overlay_check != NULL) {
 		tty_redraw_region(tty, ctx);
 		return;
 	}
@@ -1697,6 +1729,8 @@
 void
 tty_cmd_linefeed(struct tty *tty, const struct tty_ctx *ctx)
 {
+	struct client	*c = tty->client;
+
 	if (ctx->ocy != ctx->orlower)
 		return;
 
@@ -1705,7 +1739,8 @@
 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
 	    !tty_term_has(tty->term, TTYC_CSR) ||
 	    ctx->sx == 1 ||
-	    ctx->sy == 1) {
+	    ctx->sy == 1 ||
+	    c->overlay_check != NULL) {
 		tty_redraw_region(tty, ctx);
 		return;
 	}
@@ -1736,14 +1771,16 @@
 void
 tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
 {
-	u_int	i;
+	struct client	*c = tty->client;
+	u_int		 i;
 
 	if (ctx->bigger ||
 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
 	    !tty_term_has(tty->term, TTYC_CSR) ||
 	    ctx->sx == 1 ||
-	    ctx->sy == 1) {
+	    ctx->sy == 1 ||
+	    c->overlay_check != NULL) {
 		tty_redraw_region(tty, ctx);
 		return;
 	}
@@ -1772,7 +1809,8 @@
 void
 tty_cmd_scrolldown(struct tty *tty, const struct tty_ctx *ctx)
 {
-	u_int	i;
+	u_int		 i;
+	struct client	*c = tty->client;
 
 	if (ctx->bigger ||
 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
@@ -1781,7 +1819,8 @@
 	    (!tty_term_has(tty->term, TTYC_RI) &&
 	    !tty_term_has(tty->term, TTYC_RIN)) ||
 	    ctx->sx == 1 ||
-	    ctx->sy == 1) {
+	    ctx->sy == 1 ||
+	    c->overlay_check != NULL) {
 		tty_redraw_region(tty, ctx);
 		return;
 	}
@@ -1891,9 +1930,28 @@
 void
 tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
 {
-	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, 1, 1))
+	const struct grid_cell	*gcp = ctx->cell;
+	struct screen		*s = ctx->s;
+	u_int			 i, px, py;
+
+	px = ctx->xoff + ctx->ocx - ctx->wox;
+	py = ctx->yoff + ctx->ocy - ctx->woy;
+	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, 1, 1) ||
+	    (gcp->data.width == 1 && !tty_check_overlay(tty, px, py)))
 		return;
 
+	/* Handle partially obstructed wide characters. */
+	if (gcp->data.width > 1) {
+		for (i = 0; i < gcp->data.width; i++) {
+			if (!tty_check_overlay(tty, px + i, py)) {
+				tty_draw_line(tty, s, s->cx, s->cy,
+				    gcp->data.width, px, py, &ctx->defaults,
+				    ctx->palette);
+				return;
+			}
+		}
+	}
+
 	if (ctx->xoff + ctx->ocx - ctx->wox > tty->sx - 1 &&
 	    ctx->ocy == ctx->orlower &&
 	    tty_full_width(tty, ctx))
@@ -1908,6 +1966,8 @@
 void
 tty_cmd_cells(struct tty *tty, const struct tty_ctx *ctx)
 {
+	u_int	i, hide = 0;
+
 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, ctx->num, 1))
 		return;
 
@@ -1931,7 +1991,18 @@
 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
 
 	tty_attributes(tty, ctx->cell, &ctx->defaults, ctx->palette);
-	tty_putn(tty, ctx->ptr, ctx->num, ctx->num);
+	for (i = 0; i < ctx->num; i++) {
+		if (!tty_check_overlay(tty, tty->cx + i, tty->cy))
+			break;
+	}
+	tty_putn(tty, ctx->ptr, i, i);
+	for (; i < ctx->num; i++) {
+		if (tty_check_overlay(tty, tty->cx + hide, tty->cy))
+			break;
+		hide++;
+	}
+	tty_cursor(tty, tty->cx + hide, tty->cy);
+	tty_putn(tty, (char *)ctx->ptr + i, ctx->num - i, ctx->num - i);
 }
 
 void