===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/grid.c,v
retrieving revision 1.69
retrieving revision 1.70
diff -u -r1.69 -r1.70
--- src/usr.bin/tmux/grid.c	2017/04/19 12:44:29	1.69
+++ src/usr.bin/tmux/grid.c	2017/04/25 18:20:51	1.70
@@ -1,4 +1,4 @@
-/* $OpenBSD: grid.c,v 1.69 2017/04/19 12:44:29 nicm Exp $ */
+/* $OpenBSD: grid.c,v 1.70 2017/04/25 18:20:51 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -675,8 +675,7 @@
 {
 	int	oldc[64], newc[64], s[128];
 	size_t	noldc, nnewc, n, i;
-	u_int	attr = gc->attr;
-	u_int	lastattr = lastgc->attr;
+	u_int	attr = gc->attr, lastattr = lastgc->attr;
 	char	tmp[64];
 
 	struct {
@@ -708,34 +707,58 @@
 			s[n++] = attrs[i].code;
 	}
 
-	/* If the foreground colour changed, append its parameters. */
+	/* Write the attributes. */
+	*buf = '\0';
+	if (n > 0) {
+		if (escape_c0)
+			strlcat(buf, "\\033[", len);
+		else
+			strlcat(buf, "\033[", len);
+		for (i = 0; i < n; i++) {
+			if (i + 1 < n)
+				xsnprintf(tmp, sizeof tmp, "%d;", s[i]);
+			else
+				xsnprintf(tmp, sizeof tmp, "%d", s[i]);
+			strlcat(buf, tmp, len);
+		}
+		strlcat(buf, "m", len);
+	}
+
+	/* If the foreground colour changed, write its parameters. */
 	nnewc = grid_string_cells_fg(gc, newc);
 	noldc = grid_string_cells_fg(lastgc, oldc);
-	if (nnewc != noldc || memcmp(newc, oldc, nnewc * sizeof newc[0]) != 0) {
-		for (i = 0; i < nnewc; i++)
-			s[n++] = newc[i];
+	if (nnewc != noldc ||
+	    memcmp(newc, oldc, nnewc * sizeof newc[0]) != 0 ||
+	    (n != 0 && s[0] == 0)) {
+		if (escape_c0)
+			strlcat(buf, "\\033[", len);
+		else
+			strlcat(buf, "\033[", len);
+		for (i = 0; i < nnewc; i++) {
+			if (i + 1 < nnewc)
+				xsnprintf(tmp, sizeof tmp, "%d;", newc[i]);
+			else
+				xsnprintf(tmp, sizeof tmp, "%d", newc[i]);
+			strlcat(buf, tmp, len);
+		}
+		strlcat(buf, "m", len);
 	}
 
 	/* If the background colour changed, append its parameters. */
 	nnewc = grid_string_cells_bg(gc, newc);
 	noldc = grid_string_cells_bg(lastgc, oldc);
-	if (nnewc != noldc || memcmp(newc, oldc, nnewc * sizeof newc[0]) != 0) {
-		for (i = 0; i < nnewc; i++)
-			s[n++] = newc[i];
-	}
-
-	/* If there are any parameters, append an SGR code. */
-	*buf = '\0';
-	if (n > 0) {
+	if (nnewc != noldc ||
+	    memcmp(newc, oldc, nnewc * sizeof newc[0]) != 0 ||
+	    (n != 0 && s[0] == 0)) {
 		if (escape_c0)
 			strlcat(buf, "\\033[", len);
 		else
 			strlcat(buf, "\033[", len);
-		for (i = 0; i < n; i++) {
-			if (i + 1 < n)
-				xsnprintf(tmp, sizeof tmp, "%d;", s[i]);
+		for (i = 0; i < nnewc; i++) {
+			if (i + 1 < nnewc)
+				xsnprintf(tmp, sizeof tmp, "%d;", newc[i]);
 			else
-				xsnprintf(tmp, sizeof tmp, "%d", s[i]);
+				xsnprintf(tmp, sizeof tmp, "%d", newc[i]);
 			strlcat(buf, tmp, len);
 		}
 		strlcat(buf, "m", len);
@@ -744,13 +767,13 @@
 	/* Append shift in/shift out if needed. */
 	if ((attr & GRID_ATTR_CHARSET) && !(lastattr & GRID_ATTR_CHARSET)) {
 		if (escape_c0)
-			strlcat(buf, "\\016", len);  /* SO */
+			strlcat(buf, "\\016", len); /* SO */
 		else
 			strlcat(buf, "\016", len);  /* SO */
 	}
 	if (!(attr & GRID_ATTR_CHARSET) && (lastattr & GRID_ATTR_CHARSET)) {
 		if (escape_c0)
-			strlcat(buf, "\\017", len);  /* SI */
+			strlcat(buf, "\\017", len); /* SI */
 		else
 			strlcat(buf, "\017", len);  /* SI */
 	}