From 09b7a3d45cb2dd1bbeb8a665103556cea70c2479 Mon Sep 17 00:00:00 2001
From: wpaul <wpaul@FreeBSD.org>
Date: Sat, 18 Feb 1995 18:05:35 +0000
Subject: [PATCH] Do away with 'options SWAP_GENERIC' once and for all: I get
 ill just thinking about it.

Two changes need to be made to allow 'config kernel swap generic' to
work properly without requiring any compile-time flags:

/usr/src/usr.sbin/config/mkswapconf.c: we need to define a dummy stub
for the setconf() function to replace the one in swapgeneric.c that
isn't available in non-generic configurations.

/usr/src/sys/i386/i386/autoconf.c: the -a boot flag causes setroot()
to be skipped and lets setconf() prompt the user for a root device.
If you skip setroot() in a non-generic kernel, you could get severely
hosed. To avoid this, we silently ignore the -a flag if rootdev != NODEV.
(rootdev is always initialized to NODEV in swapgeneric.c, so if
we find that rootdev is something other than NODEV, we know we're
not using a generic configuration.)
---
 sys/amd64/amd64/autoconf.c   | 16 ++++++++++------
 sys/i386/i386/autoconf.c     | 16 ++++++++++------
 usr.sbin/config/mkswapconf.c |  4 +++-
 3 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/sys/amd64/amd64/autoconf.c b/sys/amd64/amd64/autoconf.c
index d00e42e47113..00d0fa91dbd4 100644
--- a/sys/amd64/amd64/autoconf.c
+++ b/sys/amd64/amd64/autoconf.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)autoconf.c	7.1 (Berkeley) 5/9/91
- *	$Id: autoconf.c,v 1.18 1995/01/11 17:51:26 jkh Exp $
+ *	$Id: autoconf.c,v 1.19 1995/02/01 23:11:38 se Exp $
  */
 
 /*
@@ -111,13 +111,17 @@ configure()
 #ifdef FFS
 	if (!mountroot) {
 		mountroot = ffs_mountroot;
-#ifdef SWAP_GENERIC
-		if ((boothowto & RB_ASKNAME) == 0)
+		/*
+		 * Ignore the -a flag if this kernel isn't compiled
+		 * with a generic root/swap configuration: if we skip
+		 * setroot() and we aren't a generic kernel, chaos
+		 * will ensue because setconf() will be a no-op.
+		 * (rootdev is always initialized to NODEV in a
+		 * generic configuration, so we test for that.)
+		 */
+		if ((boothowto & RB_ASKNAME) == 0 || rootdev != NODEV)
 			setroot();
 		setconf();
-#else
-		setroot();
-#endif
 	}
 #endif
 	if (!mountroot) {
diff --git a/sys/i386/i386/autoconf.c b/sys/i386/i386/autoconf.c
index d00e42e47113..00d0fa91dbd4 100644
--- a/sys/i386/i386/autoconf.c
+++ b/sys/i386/i386/autoconf.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)autoconf.c	7.1 (Berkeley) 5/9/91
- *	$Id: autoconf.c,v 1.18 1995/01/11 17:51:26 jkh Exp $
+ *	$Id: autoconf.c,v 1.19 1995/02/01 23:11:38 se Exp $
  */
 
 /*
@@ -111,13 +111,17 @@ configure()
 #ifdef FFS
 	if (!mountroot) {
 		mountroot = ffs_mountroot;
-#ifdef SWAP_GENERIC
-		if ((boothowto & RB_ASKNAME) == 0)
+		/*
+		 * Ignore the -a flag if this kernel isn't compiled
+		 * with a generic root/swap configuration: if we skip
+		 * setroot() and we aren't a generic kernel, chaos
+		 * will ensue because setconf() will be a no-op.
+		 * (rootdev is always initialized to NODEV in a
+		 * generic configuration, so we test for that.)
+		 */
+		if ((boothowto & RB_ASKNAME) == 0 || rootdev != NODEV)
 			setroot();
 		setconf();
-#else
-		setroot();
-#endif
 	}
 #endif
 	if (!mountroot) {
diff --git a/usr.sbin/config/mkswapconf.c b/usr.sbin/config/mkswapconf.c
index 1ffb7081cf17..4b883a4dc437 100644
--- a/usr.sbin/config/mkswapconf.c
+++ b/usr.sbin/config/mkswapconf.c
@@ -111,7 +111,9 @@ do_swap(fl)
 	} while (swap && swap->f_type == SWAPSPEC);
 	fprintf(fp, "\t{ NODEV, 0, 0 },\t/* for NFS diskless */\n");
 	fprintf(fp, "\t{ NODEV, 0, 0 }\n");
-	fprintf(fp, "};\n");
+	fprintf(fp, "};\n\n");
+	fprintf(fp, "/* Stub for when generic swap config is not used. */\n");
+	fprintf(fp, "void setconf(void) {};\n");
 	fclose(fp);
 	return (swap);
 }