From e46ff49b6d65a5969b658698445d284099516ef9 Mon Sep 17 00:00:00 2001
From: krw <krw@openbsd.org>
Date: Wed, 21 Jun 2023 12:50:09 +0000
Subject: [PATCH] Add a parameter 'action' to mpfree() so it can optionally
 discard or keep the memory pointed at by the char ** parameter.

Allows mpfree() to be used against the global mountpoints[] and
eliminates a couple of manual loops to free the current contents
of mountpoints[].

No intentional functional change.
---
 sbin/disklabel/disklabel.c |  4 ++--
 sbin/disklabel/editor.c    | 33 ++++++++++++++++-----------------
 sbin/disklabel/extern.h    |  8 ++++++--
 3 files changed, 24 insertions(+), 21 deletions(-)

diff --git a/sbin/disklabel/disklabel.c b/sbin/disklabel/disklabel.c
index 031e9197593..b520ac4c29d 100644
--- a/sbin/disklabel/disklabel.c
+++ b/sbin/disklabel/disklabel.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: disklabel.c,v 1.250 2023/06/19 13:45:19 krw Exp $	*/
+/*	$OpenBSD: disklabel.c,v 1.251 2023/06/21 12:50:09 krw Exp $	*/
 
 /*
  * Copyright (c) 1987, 1993
@@ -1005,7 +1005,7 @@ next:
 
 	if (errors > 0)
 		mpcopy(mountpoints, omountpoints);
-	mpfree(omountpoints);
+	mpfree(omountpoints, DISCARD);
 
 	return (errors > 0);
 }
diff --git a/sbin/disklabel/editor.c b/sbin/disklabel/editor.c
index 183f7e6de1a..64c534c7651 100644
--- a/sbin/disklabel/editor.c
+++ b/sbin/disklabel/editor.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: editor.c,v 1.410 2023/06/19 13:45:19 krw Exp $	*/
+/*	$OpenBSD: editor.c,v 1.411 2023/06/21 12:50:09 krw Exp $	*/
 
 /*
  * Copyright (c) 1997-2000 Todd C. Miller <millert@openbsd.org>
@@ -501,9 +501,9 @@ editor(int f)
 		}
 	}
 done:
-	mpfree(omountpoints);
-	mpfree(origmountpoints);
-	mpfree(tmpmountpoints);
+	mpfree(omountpoints, DISCARD);
+	mpfree(origmountpoints, DISCARD);
+	mpfree(tmpmountpoints, DISCARD);
 	return (error);
 }
 
@@ -556,10 +556,7 @@ again:
 	if (index >= alloc_table_nitems)
 		return 1;
 	lp = &label;
-	for (i = 0; i < MAXPARTITIONS; i++) {
-		free(mountpoints[i]);
-		mountpoints[i] = NULL;
-	}
+	mpfree(mountpoints, KEEP);
 	memcpy(lp, lp_org, sizeof(struct disklabel));
 	lp->d_npartitions = MAXPARTITIONS;
 	lastalloc = alloc_table[index].sz;
@@ -1541,17 +1538,22 @@ mpsave(const struct disklabel *lp)
 }
 
 void
-mpfree(char **mp)
+mpfree(char **mp, int action)
 {
 	int part;
 
 	if (mp == NULL)
 		return;
 
-	for (part = 0; part < MAXPARTITIONS; part++)
+	for (part = 0; part < MAXPARTITIONS; part++) {
 		free(mp[part]);
+		mp[part] = NULL;
+	}
 
-	free(mp);
+	if (action == DISCARD) {
+		free(mp);
+		mp = NULL;
+	}
 }
 
 int
@@ -1784,13 +1786,10 @@ zero_partitions(struct disklabel *lp)
 {
 	int i;
 
-	for (i = 0; i < MAXPARTITIONS; i++) {
-		memset(&lp->d_partitions[i], 0, sizeof(struct partition));
-		free(mountpoints[i]);
-		mountpoints[i] = NULL;
-	}
-
+	memset(lp->d_partitions, 0, sizeof(lp->d_partitions));
 	DL_SETPSIZE(&lp->d_partitions[RAW_PART], DL_GETDSIZE(lp));
+
+	mpfree(mountpoints, KEEP);
 }
 
 u_int64_t
diff --git a/sbin/disklabel/extern.h b/sbin/disklabel/extern.h
index 174ebc4a442..a6c7e3a1459 100644
--- a/sbin/disklabel/extern.h
+++ b/sbin/disklabel/extern.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: extern.h,v 1.35 2023/01/04 21:08:08 krw Exp $	*/
+/*	$OpenBSD: extern.h,v 1.36 2023/06/21 12:50:09 krw Exp $	*/
 
 /*
  * Copyright (c) 2003 Theo de Raadt <deraadt@openbsd.org>
@@ -19,6 +19,10 @@
 #define MEG(x)	((x) * 1024LL * (1024 / DEV_BSIZE))
 #define GIG(x)  (MEG(x) * 1024LL)
 
+/* 'actions' for mpfree(). */
+#define	DISCARD	0
+#define	KEEP	1
+
 u_short	dkcksum(const struct disklabel *);
 char	canonical_unit(const struct disklabel *, char);
 double	scale(u_int64_t, char, const struct disklabel *);
@@ -30,7 +34,7 @@ int	editor(int);
 int	editor_allocspace(struct disklabel *);
 void	mpsave(const struct disklabel *);
 void	mpcopy(char **, char **);
-void	mpfree(char **);
+void	mpfree(char **, int);
 void	parse_autotable(char *);
 
 int	writelabel(int, struct disklabel *);
-- 
2.20.1