add undo support for box, visual, cut/paste

1 files changed, 21 insertions, 17 deletions

diff --git a/lineset.c b/lineset.c
index 40fe3f0..75ae1d3 100644
--- a/lineset.c
+++ b/lineset.c
@@ -127,19 +127,24 @@ void paste_region(int x1, int y1){
 }
 
 void copy_lines_to_ring(int y1, int y2, int which){
-	lineset_t *tmp;
-	int i, len, *idx;
+	int i, len, idx;
+	int offset;
+	lineset_t *tmp;	
 
 	if (y1 > y2){
 		y1 ^= y2;
 		y2 ^= y1;
 		y1 ^= y2;
 	}
-	if (which == CUR)
-		idx = &undo_cur;
+	if (undo_cur > undo_lst)
+		undo_cur = undo_lst;
+	if (which == PRV_STATE){ /* adding a new previous state */
+		undo_cur += 2;
+		idx = undo_cur;
+	}
 	else
-		idx = &undo_lst;
-	if (*idx == undo_sz - 1){
+		idx = undo_cur + 1;
+	if (idx >= undo_sz - 1){
 		undo_sz += 10;
 		tmp = realloc(undo, undo_sz * sizeof(lineset_t));
 		if (tmp == NULL){
@@ -148,22 +153,21 @@ void copy_lines_to_ring(int y1, int y2, int which){
 		}
 		undo = tmp;
 	}
-	(*idx) ++;
-	ensure_num_lines(&(undo[*idx]), y2 - y1 + 1);
+	ensure_num_lines(&(undo[idx]), y2 - y1 + 1);
 	for(i=y1; i<=y2; i++){
 		len = strlen(screen.l[i].s);
-		ensure_line_length(&(undo[*idx].l[i-y1]), len);
-		strcpy(undo[*idx].l[i-y1].s, screen.l[i].s);
-		undo[*idx].l[i-y1].n = i;
-		undo[*idx].l[i-y1].lst = screen.l[i].lst;
+		ensure_line_length(&(undo[idx].l[i-y1]), len);
+		strcpy(undo[idx].l[i-y1].s, screen.l[i].s);
+		undo[idx].l[i-y1].n = i;
+		undo[idx].l[i-y1].lst = screen.l[i].lst;
 	}
-	undo[*idx].num = y2 - y1 + 1;
-	if (which == CUR)
+	undo[idx].num = y2 - y1 + 1;
+	if (which == PRV_STATE)
 		undo_lst = undo_cur;
 #ifdef DEBUG
-	fprintf(stderr, "undo_ring: y1: %d y2: %d idx: %d\n", y1, y2, *idx);
-	for(i=0; i<undo[undo_cur].num; i++){
-		fprintf(stderr, "UU: %d| %s\n", undo[*idx].l[i].n, undo[*idx].l[i].s);
+	fprintf(stderr, "undo_ring: y1: %d y2: %d idx: %d\n", y1, y2, idx);
+	for(i=0; i<undo[idx].num; i++){
+		fprintf(stderr, "UU: %d| %s\n", undo[idx].l[i].n, undo[idx].l[i].s);
 	}
 #endif	
 }