Expose the undo commands as proper mg functions.

This should have no functional change on undo, but it does facilitate
testing undo behavior.

10 files changed, 94 insertions, 71 deletions

diff --git a/usr.bin/mg/cmode.c b/usr.bin/mg/cmode.c
index e728a8eccf2..ed9598011f1 100644
--- a/usr.bin/mg/cmode.c
+++ b/usr.bin/mg/cmode.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: cmode.c,v 1.4 2008/06/14 08:39:30 kjell Exp $ */
+/* $OpenBSD: cmode.c,v 1.5 2008/09/15 16:13:35 kjell Exp $ */
 /*
  * This file is in the public domain.
  *
@@ -164,8 +164,7 @@ cc_indent(int f, int n)
 	if (n < 0)
 		return (FALSE);
 
-	undo_add_boundary();
-	undo_boundary_enable(FALSE);
+	undo_boundary_enable(FFRAND, 0);
 	if (cc_strip_trailp)
 		deltrailwhite(FFRAND, 1);
 
@@ -188,8 +187,7 @@ cc_indent(int f, int n)
 	else
 		ret = indent(FFOTHARG, pi + ci);
 	
-	undo_boundary_enable(TRUE);
-	undo_add_boundary();
+	undo_boundary_enable(FFRAND, 1);
 	
 	return (ret);
 }
diff --git a/usr.bin/mg/def.h b/usr.bin/mg/def.h
index 542a07c084e..aee87b081bc 100644
--- a/usr.bin/mg/def.h
+++ b/usr.bin/mg/def.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: def.h,v 1.107 2008/09/15 16:11:35 kjell Exp $	*/
+/*	$OpenBSD: def.h,v 1.108 2008/09/15 16:13:35 kjell Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -609,12 +609,12 @@ int		 cntnonmatchlines(int, int);
 void		 free_undo_record(struct undo_rec *);
 int		 undo_dump(int, int);
 int		 undo_enabled(void);
-int		 undo_enable(int);
-void		 undo_add_boundary(void);
+int		 undo_enable(int, int);
+int		 undo_add_boundary(int, int);
 void		 undo_add_modified(void);
 int		 undo_add_insert(struct line *, int, int);
 int		 undo_add_delete(struct line *, int, int);
-void		 undo_boundary_enable(int);
+int		 undo_boundary_enable(int, int);
 int		 undo_add_change(struct line *, int, int);
 int		 undo(int, int);
 
diff --git a/usr.bin/mg/file.c b/usr.bin/mg/file.c
index 6f3f87f7d78..9c5aac36b9b 100644
--- a/usr.bin/mg/file.c
+++ b/usr.bin/mg/file.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: file.c,v 1.68 2008/09/15 16:11:35 kjell Exp $	*/
+/*	$OpenBSD: file.c,v 1.69 2008/09/15 16:13:35 kjell Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -293,7 +293,7 @@ insertfile(char *fname, char *newname, int replacebuf)
 	char *dp;
 
 	if (replacebuf == TRUE)
-		x = undo_enable(FALSE);
+		x = undo_enable(FFRAND, 0);
 	else
 		x = undo_enabled();
 
@@ -335,7 +335,7 @@ insertfile(char *fname, char *newname, int replacebuf)
 		killbuffer(bp);
 		if ((bp = dired_(fname)) == NULL)
 			return (FALSE);
-		undo_enable(x);
+		undo_enable(FFRAND, x);
 		curbp = bp;
 		return (showbuffer(bp, curwp, WFFULL | WFMODE));
 	} else {
@@ -351,10 +351,10 @@ insertfile(char *fname, char *newname, int replacebuf)
 	 * We will delete this newline after insertion.
 	 * Disable undo, as we create the undo record manually.
 	 */
-	x2 = undo_enable(FALSE);
+	x2 = undo_enable(FFRAND, 0);
 	(void)lnewline();
 	olp = lback(curwp->w_dotp);
-	undo_enable(x2);
+	undo_enable(FFRAND, x2);
 
 	nline = 0;
 	siz = 0;
@@ -477,7 +477,7 @@ out:		lp2 = NULL;
 	}
 	bp->b_lines += nline;
 cleanup:
-	undo_enable(x);
+	undo_enable(FFRAND, x);
 
 	/* return FALSE if error */
 	return (s != FIOERR);
diff --git a/usr.bin/mg/funmap.c b/usr.bin/mg/funmap.c
index 056658b5224..d620743ebb1 100644
--- a/usr.bin/mg/funmap.c
+++ b/usr.bin/mg/funmap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: funmap.c,v 1.31 2008/06/14 08:46:30 kjell Exp $	*/
+/*	$OpenBSD: funmap.c,v 1.32 2008/09/15 16:13:35 kjell Exp $	*/
 
 /* This file is in the public domain */
 
@@ -181,6 +181,9 @@ static struct funmap functnames[] = {
 	{togglereadonly, "toggle-read-only" },
 	{twiddle, "transpose-chars",},
 	{undo, "undo", },
+	{undo_enable, "undo-enable", },
+	{undo_boundary_enable, "undo-boundary-toggle", },
+	{undo_add_boundary, "undo-boundary", },
 	{undo_dump, "undo-list", },
 	{universal_argument, "universal-argument",},
 	{upperregion, "upcase-region",},
diff --git a/usr.bin/mg/line.c b/usr.bin/mg/line.c
index 4d0565e0afe..840c3adf3d9 100644
--- a/usr.bin/mg/line.c
+++ b/usr.bin/mg/line.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: line.c,v 1.45 2008/09/15 16:11:35 kjell Exp $	*/
+/*	$OpenBSD: line.c,v 1.46 2008/09/15 16:13:35 kjell Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -352,9 +352,9 @@ lnewline_at(struct line *lp1, int doto)
 		for (wp = wheadp; wp != NULL; wp = wp->w_wndp)
 			if (wp->w_linep == lp1)
 				wp->w_linep = lp2;
-		undo_add_boundary();
+		undo_add_boundary(FFRAND, 1);
 		undo_add_insert(lp2, 0, 1);
-		undo_add_boundary();
+		undo_add_boundary(FFRAND, 1);
 		return (TRUE);
 	}
 
@@ -382,9 +382,9 @@ lnewline_at(struct line *lp1, int doto)
 			wp->w_marko -= doto;
 		}
 	}
-	undo_add_boundary();
+	undo_add_boundary(FFRAND, 1);
 	undo_add_insert(lp1, llength(lp1), 1);
-	undo_add_boundary();
+	undo_add_boundary(FFRAND, 1);
 	return (TRUE);
 }
 
@@ -596,8 +596,7 @@ lreplace(RSIZE plen, char *st)
 		ewprintf("Buffer is read only");
 		return (FALSE);
 	}
-	undo_add_boundary();
-	undo_boundary_enable(FALSE);
+	undo_boundary_enable(FFRAND, 0);
 
 	(void)backchar(FFARG | FFRAND, (int)plen);
 	(void)ldelete(plen, KNONE);
@@ -606,8 +605,7 @@ lreplace(RSIZE plen, char *st)
 	region_put_data(st, rlen);
 	lchange(WFFULL);
 
-	undo_boundary_enable(TRUE);
-	undo_add_boundary();
+	undo_boundary_enable(FFRAND, 1);
 	return (TRUE);
 }
 
diff --git a/usr.bin/mg/mg.1 b/usr.bin/mg/mg.1
index d7f01e7f463..9c40640420e 100644
--- a/usr.bin/mg/mg.1
+++ b/usr.bin/mg/mg.1
@@ -1,7 +1,7 @@
-.\"	$OpenBSD: mg.1,v 1.40 2008/06/29 08:28:01 sobrado Exp $
+.\"	$OpenBSD: mg.1,v 1.41 2008/09/15 16:13:35 kjell Exp $
 .\" This file is in the public domain.
 .\"
-.Dd $Mdocdate: June 29 2008 $
+.Dd $Mdocdate: September 15 2008 $
 .Dt MG 1
 .Os
 .Sh NAME
@@ -736,6 +736,15 @@ make this work.
 Undo the most recent action.
 If invoked again without an intervening command,
 move the undo pointer to the previous action and undo it.
+.It undo-boundary
+Add an undo boundary.
+This is not usually done interactively.
+.It undo-boundary-toggle
+Toggle whether undo boundaries are generated.
+Undo boundaries are often disabled before operations that should
+be considered atomically undoable.
+.It undo-enable
+Toggle whether undo information is kept.
 .It undo-list
 Show the undo records for the current buffer in a new buffer.
 .It universal-argument
diff --git a/usr.bin/mg/paragraph.c b/usr.bin/mg/paragraph.c
index a4378977a22..0ef46bd38d5 100644
--- a/usr.bin/mg/paragraph.c
+++ b/usr.bin/mg/paragraph.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: paragraph.c,v 1.16 2008/06/12 21:36:47 kjell Exp $	*/
+/*	$OpenBSD: paragraph.c,v 1.17 2008/09/15 16:13:35 kjell Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -130,8 +130,7 @@ fillpara(int f, int n)
 	struct line	*eopline;	/* pointer to line just past EOP	*/
 	char	 wbuf[MAXWORD];	/* buffer for current word		*/
 
-	undo_add_boundary();
-	undo_boundary_enable(FALSE);
+	undo_boundary_enable(FFRAND, 0);
 
 	/* record the pointer to the line just past the EOP */
 	(void)gotoeop(FFRAND, 1);
@@ -237,8 +236,7 @@ fillpara(int f, int n)
 	(void)backchar(FFRAND, 1);
 	retval = TRUE;
 cleanup:
-	undo_boundary_enable(TRUE);
-	undo_add_boundary();
+	undo_boundary_enable(FFRAND, 1);
 	return (retval);
 }
 
diff --git a/usr.bin/mg/random.c b/usr.bin/mg/random.c
index e53a5489d4e..8a34e495e75 100644
--- a/usr.bin/mg/random.c
+++ b/usr.bin/mg/random.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: random.c,v 1.25 2008/06/11 23:18:33 kjell Exp $	*/
+/*	$OpenBSD: random.c,v 1.26 2008/09/15 16:13:35 kjell Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -119,8 +119,7 @@ twiddle(int f, int n)
 
 	dotp = curwp->w_dotp;
 	doto = curwp->w_doto;
-	undo_add_boundary();
-	undo_boundary_enable(FALSE);
+	undo_boundary_enable(FFRAND, 0);
 	if (doto == llength(dotp)) {
 		if (--doto <= 0)
 			return (FALSE);
@@ -136,8 +135,7 @@ twiddle(int f, int n)
 	linsert(1, cr);
 	if (fudge != TRUE)
 		(void)backchar(FFRAND, 1);
-	undo_boundary_enable(TRUE);
-	undo_add_boundary();
+	undo_boundary_enable(FFRAND, 1);
 	lchange(WFEDIT);
 	return (TRUE);
 }
diff --git a/usr.bin/mg/undo.c b/usr.bin/mg/undo.c
index f4206a86a74..fe8b53bfeed 100644
--- a/usr.bin/mg/undo.c
+++ b/usr.bin/mg/undo.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: undo.c,v 1.46 2008/06/14 07:38:53 kjell Exp $ */
+/* $OpenBSD: undo.c,v 1.47 2008/09/15 16:13:35 kjell Exp $ */
 /*
  * This file is in the public domain
  */
@@ -159,56 +159,77 @@ undo_enabled(void)
 }
 
 /*
- * undo_enable(TRUE/FALSE) will enable / disable the undo mechanism.
- * Returns TRUE if previously enabled, FALSE otherwise.
+ * undo_enable: toggle undo_enable.
+ * Returns the previous value of the flag.
  */
 int
-undo_enable(int on)
+undo_enable(int f, int n)
 {
 	int pon = undo_enable_flag;
 
-	undo_enable_flag = on;
+	if (f & (FFARG | FFRAND))
+		undo_enable_flag = n > 0;
+	else
+		undo_enable_flag = !undo_enable_flag;
+
+	if (!(f & FFRAND))
+		ewprintf("Undo %sabled", undo_enable_flag ? "en" : "dis");
+
 	return (pon);
 }
 
 /*
  * If undo is enabled, then:
- *   undo_boundary_enable(FALSE) stops recording undo boundaries
- *   between actions.
- *   undo_boundary_enable(TRUE) enables undo boundaries.
+ *  Toggle undo boundary recording.
+ *  If called with an argument, (n > 0) => enable. Otherwise disable.
+ * In either case, add an undo boundary
  * If undo is disabled, this function has no effect.
  */
-
-void
-undo_boundary_enable(int flag)
+int
+undo_boundary_enable(int f, int n)
 {
-	if (undo_enable_flag == TRUE)
-		boundary_flag = flag;
+	int bon = boundary_flag;
+
+	if (!undo_enable_flag)
+		return (FALSE);
+
+	undo_add_boundary(FFRAND, 1);
+
+	if (f & (FFARG | FFRAND))
+		boundary_flag = n > 0;
+	else
+		boundary_flag = !boundary_flag;
+
+	if (!(f & FFRAND))
+		ewprintf("Undo boundaries %sabled",
+		    boundary_flag ? "en" : "dis");
+
+	return (bon);
 }
 
 /*
  * Record an undo boundary, unless boundary_flag == FALSE.
  * Does nothing if previous undo entry is already a boundary or 'modified' flag.
  */
-void
-undo_add_boundary(void)
+int
+undo_add_boundary(int f, int n)
 {
 	struct undo_rec *rec;
 	int last;
 
 	if (boundary_flag == FALSE)
-		return;
+		return (FALSE);
 
 	last = lastrectype();
 	if (last == BOUNDARY || last == MODIFIED)
-		return;
+		return (TRUE);
 
 	rec = new_undo_record();
 	rec->type = BOUNDARY;
 
 	LIST_INSERT_HEAD(&curbp->b_undo, rec, next);
 
-	return;
+	return (TRUE);
 }
 
 /*
@@ -234,7 +255,7 @@ undo_add_insert(struct line *lp, int offset, int size)
 	struct	undo_rec *rec;
 	int	pos;
 
-	if (undo_enable_flag == FALSE)
+	if (!undo_enable_flag)
 		return (TRUE);
 	reg.r_linep = lp;
 	reg.r_offset = offset;
@@ -262,7 +283,7 @@ undo_add_insert(struct line *lp, int offset, int size)
 	memmove(&rec->region, &reg, sizeof(struct region));
 	rec->content = NULL;
 
-	undo_add_boundary();
+	undo_add_boundary(FFRAND, 1);
 
 	LIST_INSERT_HEAD(&curbp->b_undo, rec, next);
 
@@ -279,7 +300,7 @@ undo_add_delete(struct line *lp, int offset, int size)
 	struct	undo_rec *rec;
 	int	pos;
 
-	if (undo_enable_flag == FALSE)
+	if (!undo_enable_flag)
 		return (TRUE);
 
 	reg.r_linep = lp;
@@ -289,7 +310,7 @@ undo_add_delete(struct line *lp, int offset, int size)
 	pos = find_dot(lp, offset);
 
 	if (offset == llength(lp))	/* if it's a newline... */
-		undo_add_boundary();
+		undo_add_boundary(FFRAND, 1);
 	else if ((rec = LIST_FIRST(&curbp->b_undo)) != NULL) {
 		/*
 		 * Separate this command from the previous one if we're not
@@ -297,7 +318,7 @@ undo_add_delete(struct line *lp, int offset, int size)
 		 */
 		if (rec->type == DELETE) {
 			if (rec->pos - rec->region.r_size != pos)
-				undo_add_boundary();
+				undo_add_boundary(FFRAND, 1);
 		}
 	}
 	rec = new_undo_record();
@@ -315,7 +336,7 @@ undo_add_delete(struct line *lp, int offset, int size)
 	region_get_data(&reg, rec->content, reg.r_size);
 
 	if (lastrectype() != DELETE)
-		undo_add_boundary();
+		undo_add_boundary(FFRAND, 1);
 
 	LIST_INSERT_HEAD(&curbp->b_undo, rec, next);
 
@@ -328,14 +349,14 @@ undo_add_delete(struct line *lp, int offset, int size)
 int
 undo_add_change(struct line *lp, int offset, int size)
 {
-	if (undo_enable_flag == FALSE)
+	if (!undo_enable_flag)
 		return (TRUE);
-	undo_add_boundary();
+	undo_add_boundary(FFRAND, 1);
 	boundary_flag = FALSE;
 	undo_add_delete(lp, offset, size);
 	undo_add_insert(lp, offset, size);
 	boundary_flag = TRUE;
-	undo_add_boundary();
+	undo_add_boundary(FFRAND, 1);
 
 	return (TRUE);
 }
@@ -484,7 +505,7 @@ undo(int f, int n)
 		 * finished the current action...
 		 */
 
-		undo_add_boundary();
+		undo_add_boundary(FFRAND, 1);
 
 		save = boundary_flag;
 		boundary_flag = FALSE;
@@ -541,7 +562,7 @@ undo(int f, int n)
 		} while (ptr != NULL && !done);
 
 		boundary_flag = save;
-		undo_add_boundary();
+		undo_add_boundary(FFRAND, 1);
 
 		ewprintf("Undo!");
 	}
diff --git a/usr.bin/mg/yank.c b/usr.bin/mg/yank.c
index 42dfa1ecfb5..c178347a72e 100644
--- a/usr.bin/mg/yank.c
+++ b/usr.bin/mg/yank.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: yank.c,v 1.6 2006/11/19 16:51:19 deraadt Exp $	*/
+/*	$OpenBSD: yank.c,v 1.7 2008/09/15 16:13:35 kjell Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -222,8 +222,7 @@ yank(int f, int n)
 	/* newline counting */
 	nline = 0;
 
-	undo_add_boundary();
-	undo_boundary_enable(FALSE);
+	undo_boundary_enable(FFRAND, 0);
 	while (n--) {
 		/* mark around last yank */
 		isetmark();
@@ -251,8 +250,7 @@ yank(int f, int n)
 		curwp->w_linep = lp;
 		curwp->w_flag |= WFFULL;
 	}
-	undo_boundary_enable(TRUE);
-	undo_add_boundary();
+	undo_boundary_enable(FFRAND, 1);
 	return (TRUE);
 }