Fix two copy mode problems:

1. In vi mode the selection doesn't include the last character if you
   moved the cursor up or left.
2. In emacs mode the selection includes the last character if you moved
   the cursor to the left.

From Balazs Kezes.

3 files changed, 20 insertions, 5 deletions

diff --git a/screen.c b/screen.c
index 2b0e9fba..3e7d9924 100644
--- a/screen.c
+++ b/screen.c
@@ -276,6 +276,7 @@ int
 screen_check_selection(struct screen *s, u_int px, u_int py)
 {
 	struct screen_sel	*sel = &s->sel;
+	u_int			 xx;
 
 	if (!sel->flag)
 		return (0);
@@ -325,16 +326,24 @@ screen_check_selection(struct screen *s, u_int px, u_int py)
 			if (py < sel->sy || py > sel->ey)
 				return (0);
 
-			if ((py == sel->sy && px < sel->sx)
-			    || (py == sel->ey && px > sel->ex))
+			if (py == sel->sy && px < sel->sx)
+				return 0;
+
+			if (py == sel->ey && px > sel->ex)
 				return (0);
 		} else if (sel->sy > sel->ey) {
 			/* starting line > ending line -- upward selection. */
 			if (py > sel->sy || py < sel->ey)
 				return (0);
 
-			if ((py == sel->sy && px >= sel->sx)
-			    || (py == sel->ey && px < sel->ex))
+			if (py == sel->ey && px < sel->ex)
+				return (0);
+
+			if (sel->modekeys == MODEKEY_EMACS)
+				xx = sel->sx - 1;
+			else
+				xx = sel->sx;
+			if (py == sel->sy && px > xx)
 				return (0);
 		} else {
 			/* starting line == ending line. */
@@ -343,7 +352,11 @@ screen_check_selection(struct screen *s, u_int px, u_int py)
 
 			if (sel->ex < sel->sx) {
 				/* cursor (ex) is on the left */
-				if (px > sel->sx || px < sel->ex)
+				if (sel->modekeys == MODEKEY_EMACS)
+					xx = sel->sx - 1;
+				else
+					xx = sel->sx;
+				if (px > xx || px < sel->ex)
 					return (0);
 			} else {
 				/* selection start (sx) is on the left */
diff --git a/tmux.h b/tmux.h
index a0cbbd41..bfc70544 100644
--- a/tmux.h
+++ b/tmux.h
@@ -794,6 +794,7 @@ LIST_HEAD(joblist, job);
 struct screen_sel {
 	int		 flag;
 	int		 rectflag;
+	int		 modekeys;
 
 	u_int		 sx;
 	u_int		 sy;
diff --git a/window-copy.c b/window-copy.c
index 17f9751b..24f94121 100644
--- a/window-copy.c
+++ b/window-copy.c
@@ -199,6 +199,7 @@ window_copy_init(struct window_pane *wp)
 		mode_key_init(&data->mdata, &mode_key_tree_emacs_copy);
 	else
 		mode_key_init(&data->mdata, &mode_key_tree_vi_copy);
+	s->sel.modekeys = keys;
 
 	data->backing = NULL;