From a05b5f9b08cd36ac2df5871787af502f89b049b0 Mon Sep 17 00:00:00 2001
From: Matthew Dillon <dillon@dragonflybsd.org>
Date: Thu, 21 Sep 2006 00:18:13 +0000
Subject: [PATCH] Fix a bug in the script softlink code.  The softlinks were
 not being properly updated because 'ln -sf' creates a softlink in the
 directory pointed to by the existing softlink rather then replacing the
 existing softlink.

---
 bin/cpdup/BACKUPS                | 17 +++++++++++------
 bin/cpdup/scripts/do_mirror_host |  5 +++--
 bin/cpdup/scripts/do_remote_host |  4 ++--
 3 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/bin/cpdup/BACKUPS b/bin/cpdup/BACKUPS
index b893012eb1..8c3513a75c 100644
--- a/bin/cpdup/BACKUPS
+++ b/bin/cpdup/BACKUPS
@@ -1,4 +1,4 @@
-$DragonFly: src/bin/cpdup/BACKUPS,v 1.1 2006/09/16 21:57:08 dillon Exp $
+$DragonFly: src/bin/cpdup/BACKUPS,v 1.2 2006/09/21 00:18:11 dillon Exp $
 
 			    INCREMENTAL BACKUP HOWTO
 
@@ -72,10 +72,14 @@ $DragonFly: src/bin/cpdup/BACKUPS,v 1.1 2006/09/16 21:57:08 dillon Exp $
 	cpdup -i0 -s0 /nfs/box1/var /backup/mirrors/box1.${date}/var
 
     Create a softlink to the most recently completed backup, which is your
-    level 0 backup.
+    level 0 backup.  Note that using 'ln -sf' will create a link in the
+    subdirectory pointed to by the current link, not replace the current
+    link. 'ln -shf' can be used to replace the link but is not portable.
+    'mv -f' has the same problem.
 
 	sync
-	ln -fs /backup/mirrors/box1.${date} /backup/mirrors/box1
+	rm -f /backup/mirrors/box1
+	ln -s /backup/mirrors/box1.${date} /backup/mirrors/box1
 
 			PART 3 - DO AN INCREMENTAL BACKUP
 
@@ -102,7 +106,8 @@ $DragonFly: src/bin/cpdup/BACKUPS,v 1.1 2006/09/16 21:57:08 dillon Exp $
     if the cpdup's for all the partitions for that client have succeeded.
     That way the next incremental backup will be based on the previous one.
 
-	ln -fs /backup/mirrors/box1.${date} /backup/mirrors/box1
+	rm -f /backup/mirrors/box1
+	ln -s /backup/mirrors/box1.${date} /backup/mirrors/box1
 
     Since these backups are mirrors, locating a backup is as simple
     as CDing into the appropriate directory.  If your filesystem has a
@@ -169,7 +174,7 @@ $DragonFly: src/bin/cpdup/BACKUPS,v 1.1 2006/09/16 21:57:08 dillon Exp $
 
 	if ( $status == 0 ) then
 	    ssh remote.box -n \
-		"ln -fs /backup/mirrors/$latest /backup/mirrors/box1"
+		"rm -f /backup/mirrors/box1; ln -s /backup/mirrors/$latest /backup/mirrors/box1"
 	endif
 
     Incremental backups can be accomplished using the same cpdup command,
@@ -187,7 +192,7 @@ $DragonFly: src/bin/cpdup/BACKUPS,v 1.1 2006/09/16 21:57:08 dillon Exp $
 	      -i0 -s0 /backup/mirrors/$latest remote.box:/backup/mirrors/$latest
 	if ( $status == 0 ) then
 	    ssh remote.box -n \
-		"ln -fs /backup/mirrors/$latest /backup/mirrors/box1"
+		"rm -f /backup/mirrors/box1; ln -s /backup/mirrors/$latest /backup/mirrors/box1"
 	endif
 
     Cleaning out the remote directory works the same as cleaning out the LAN
diff --git a/bin/cpdup/scripts/do_mirror_host b/bin/cpdup/scripts/do_mirror_host
index 0d2e153e47..a733de3196 100755
--- a/bin/cpdup/scripts/do_mirror_host
+++ b/bin/cpdup/scripts/do_mirror_host
@@ -1,6 +1,6 @@
 #!/bin/csh
 #
-# $DragonFly: src/bin/cpdup/scripts/do_mirror_host,v 1.1 2006/09/16 21:57:10 dillon Exp $
+# $DragonFly: src/bin/cpdup/scripts/do_mirror_host,v 1.2 2006/09/21 00:18:13 dillon Exp $
 
 source params
 
@@ -95,7 +95,8 @@ end
 # rename the log file.
 #
 if ( $failed == 0 ) then
-    ln -sf "$host.$date" $backup_path/mirrors/$host
+    rm -f $backup_path/mirrors/$host
+    ln -s "$host.$date" $backup_path/mirrors/$host
     mv $backup_path/mirrors/$target/{INPROGRESS,SUCCEEDED}
     sync
     echo "SUCCEEDED"
diff --git a/bin/cpdup/scripts/do_remote_host b/bin/cpdup/scripts/do_remote_host
index a50278720b..e1913bd2ea 100755
--- a/bin/cpdup/scripts/do_remote_host
+++ b/bin/cpdup/scripts/do_remote_host
@@ -1,6 +1,6 @@
 #!/bin/csh
 #
-# $DragonFly: src/bin/cpdup/scripts/do_remote_host,v 1.1 2006/09/16 21:57:10 dillon Exp $
+# $DragonFly: src/bin/cpdup/scripts/do_remote_host,v 1.2 2006/09/21 00:18:13 dillon Exp $
 
 source params
 
@@ -99,7 +99,7 @@ default:
 endsw
 
 if ( $failed == 0 ) then
-    ssh $remote_host -n "ln -sf $basename ${remote_path}/mirrors/$host"
+    ssh $remote_host -n "rm -f ${remote_path}/mirrors/$host; ln -s $basename ${remote_path}/mirrors/$host"
     sync
     echo "SUCCEEDED"
     exit 0
-- 
2.41.0