preliminary support for undo

1 files changed, 43 insertions, 0 deletions

diff --git a/lineset.c b/lineset.c
index f672798..40fe3f0 100644
--- a/lineset.c
+++ b/lineset.c
@@ -58,6 +58,7 @@ void ensure_num_lines(lineset_t *ls, int n){
 	}
 }
 
+
 void dump_lines(lineset_t ls, FILE *f){
 	int i;
 	for (i=0; i<ls.num ;i++){
@@ -124,3 +125,45 @@ void paste_region(int x1, int y1){
 	}
 	redraw();
 }
+
+void copy_lines_to_ring(int y1, int y2, int which){
+	lineset_t *tmp;
+	int i, len, *idx;
+
+	if (y1 > y2){
+		y1 ^= y2;
+		y2 ^= y1;
+		y1 ^= y2;
+	}
+	if (which == CUR)
+		idx = &undo_cur;
+	else
+		idx = &undo_lst;
+	if (*idx == undo_sz - 1){
+		undo_sz += 10;
+		tmp = realloc(undo, undo_sz * sizeof(lineset_t));
+		if (tmp == NULL){
+			fprintf(stderr, "Error allocating undo buffer");
+			exit(1);
+		}
+		undo = tmp;
+	}
+	(*idx) ++;
+	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;
+	}
+	undo[*idx].num = y2 - y1 + 1;
+	if (which == CUR)
+		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);
+	}
+#endif	
+}