linenoise: undo feature.

* linenoise/linenoise.c (LINENOISE_MAX_UNDO): New preprocessor
symbol.
(struct lino_state): New member, undo_stack.
(struct lino_undo): New struct type.
(free_undo, record_undo, record_triv_undo, restore_undo):
New static functions.
(edit_insert): Record trivial undo item with record_triv_undo.
(edit_insert_str, edit_history_next, edit_delete,
edit_backspace, edit_delete_prev_all, edit_delete_prev_word,
edit_in_editor): Record undo item.
(edit): Record undo item before Ctrl-R history recall and
Ctrl-T twiddle. Also record one final undo item upon Enter, as
well as Ctrl-C.  New Ctrl-O command to undo.
(lino_copy): Do not copy undo_stack, to prevent double
freeing.
(lino_free): Free the undo history.

* txr.1: Documented.

0 files changed, 0 insertions, 0 deletions