Add a new "-S" flag to dump to allow it just print out dump estimate

size and then exit.

PR:		bin/35450
Submitted by:	Mark Hannon <markhannon@optushome.com.au>
Obtained from:	NetBSD
MFC after:	1 week

2 files changed, 20 insertions, 5 deletions

diff --git a/sbin/dump/dump.8 b/sbin/dump/dump.8
index a6362c1..0191da1 100644
--- a/sbin/dump/dump.8
+++ b/sbin/dump/dump.8
@@ -33,7 +33,7 @@
 .\"     @(#)dump.8	8.3 (Berkeley) 5/1/95
 .\" $FreeBSD$
 .\"
-.Dd July 9, 2001
+.Dd March 1, 2002
 .Dt DUMP 8
 .Os
 .Sh NAME
@@ -42,7 +42,7 @@
 .Nd filesystem backup
 .Sh SYNOPSIS
 .Nm
-.Op Fl 0123456789acknu
+.Op Fl 0123456789acknSu
 .Op Fl B Ar records
 .Op Fl b Ar blocksize
 .Op Fl D Ar dumpdates
@@ -194,6 +194,9 @@ If this amount is exceeded,
 prompts for a new tape.
 It is recommended to be a bit conservative on this option.
 The default tape length is 2300 feet.
+.It Fl S
+Display an estimate of the backup size and the number of
+tapes required, and exit without actually performing the dump.
 .It Fl T Ar date
 Use the specified date as the starting time for the dump
 instead of the time determined from looking in
diff --git a/sbin/dump/main.c b/sbin/dump/main.c
index 666b65f..e1fc40d 100644
--- a/sbin/dump/main.c
+++ b/sbin/dump/main.c
@@ -99,6 +99,7 @@ main(argc, argv)
 	char *map;
 	int ch;
 	int i, anydirskipped, bflag = 0, Tflag = 0, honorlevel = 1;
+	int just_estimate = 0;
 	ino_t maxino;
 	char *tmsg;
 	time_t t;
@@ -119,9 +120,9 @@ main(argc, argv)
 
 	obsolete(&argc, &argv);
 #ifdef KERBEROS
-#define optstring "0123456789aB:b:cd:f:h:kns:T:uWwD:"
+#define optstring "0123456789aB:b:cd:f:h:kns:ST:uWwD:"
 #else
-#define optstring "0123456789aB:b:cd:f:h:ns:T:uWwD:"
+#define optstring "0123456789aB:b:cd:f:h:ns:ST:uWwD:"
 #endif
 	while ((ch = getopt(argc, argv, optstring)) != -1)
 #undef optstring
@@ -182,6 +183,10 @@ main(argc, argv)
 			tsize = numarg("tape size", 1L, 0L) * 12 * 10;
 			break;
 
+		case 'S':               /* exit after estimating # of tapes */
+			just_estimate = 1;
+			break;
+
 		case 'T':		/* time of last dump */
 			spcl.c_ddate = unctime(optarg);
 			if (spcl.c_ddate < 0) {
@@ -420,6 +425,13 @@ main(argc, argv)
 		    tapesize, fetapes);
 	}
 
+        /*
+         * If the user only wants an estimate of the number of
+         * tapes, exit now.
+         */
+        if (just_estimate)
+                exit(0);
+
 	/*
 	 * Allocate tape buffer.
 	 */
@@ -508,7 +520,7 @@ usage()
 #ifdef KERBEROS
 		"k"
 #endif
-		"nu] [-B records] [-b blocksize] [-D dumpdates]\n"
+		"nSu] [-B records] [-b blocksize] [-D dumpdates]\n"
 		"            [-d density] [-f file ] [-h level] [-s feet] "
 		"[-T date] filesystem\n"
 		"       dump [-W | -w]\n");