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authorTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
committerTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
commitd6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch)
treeece253b876159b39c620e62b6c9b1174642e070e /usr.bin/vi/ex/ex_undo.c
initial import of NetBSD tree
Diffstat (limited to 'usr.bin/vi/ex/ex_undo.c')
-rw-r--r--usr.bin/vi/ex/ex_undo.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/usr.bin/vi/ex/ex_undo.c b/usr.bin/vi/ex/ex_undo.c
new file mode 100644
index 00000000000..1b8ba691682
--- /dev/null
+++ b/usr.bin/vi/ex/ex_undo.c
@@ -0,0 +1,103 @@
+/*-
+ * Copyright (c) 1992, 1993, 1994
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)ex_undo.c 8.9 (Berkeley) 8/17/94";
+#endif /* not lint */
+
+#include <sys/types.h>
+#include <sys/queue.h>
+#include <sys/time.h>
+
+#include <bitstring.h>
+#include <limits.h>
+#include <signal.h>
+#include <stdio.h>
+#include <termios.h>
+
+#include "compat.h"
+#include <db.h>
+#include <regex.h>
+
+#include "vi.h"
+#include "excmd.h"
+
+/*
+ * ex_undo -- u
+ * Undo the last change.
+ */
+int
+ex_undo(sp, ep, cmdp)
+ SCR *sp;
+ EXF *ep;
+ EXCMDARG *cmdp;
+{
+ MARK m;
+
+ /*
+ * !!!
+ * Historic undo always set the previous context mark.
+ */
+ m.lno = sp->lno;
+ m.cno = sp->cno;
+ if (mark_set(sp, ep, ABSMARK1, &m, 1))
+ return (1);
+
+ /*
+ * !!!
+ * Multiple undo isn't available in ex, as there's no '.' command.
+ * Whether 'u' is undo or redo is toggled each time, unless there
+ * was a change since the last undo, in which case it's an undo.
+ */
+ if (!F_ISSET(ep, F_UNDO)) {
+ F_SET(ep, F_UNDO);
+ ep->lundo = FORWARD;
+ }
+ switch (ep->lundo) {
+ case BACKWARD:
+ if (log_forward(sp, ep, &m))
+ return (1);
+ ep->lundo = FORWARD;
+ break;
+ case FORWARD:
+ if (log_backward(sp, ep, &m))
+ return (1);
+ ep->lundo = BACKWARD;
+ break;
+ case NOTSET:
+ abort();
+ }
+ sp->lno = m.lno;
+ sp->cno = m.cno;
+ return (0);
+}