From 66cb557a9ab03de4eff810547136c39b78b2b781 Mon Sep 17 00:00:00 2001
From: Sergey Poznyakoff <gray@gnu.org.ua>
Date: Sun, 15 Sep 2019 23:12:18 +0200
Subject: Implement version checking.

New option -p.
Fix -q option.
---
 slackware-upgrade-system   | 25 ++++++++++++++++++++++---
 slackware-upgrade-system.8 |  4 ++++
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/slackware-upgrade-system b/slackware-upgrade-system
index 4b66255..5979758 100644
--- a/slackware-upgrade-system
+++ b/slackware-upgrade-system
@@ -33,6 +33,8 @@ install_all=
 # Names of the series that should be installed in addition to already installed
 # packages.  Ignored, if install_all is set.
 install_series=
+# Names of additional packages.
+install_packages=
 # Name of the keep-list file.
 keep_file=
 
@@ -80,6 +82,7 @@ Options are:
   -h             display this help list and exit
   -k FILE        preserve packages listed in FILE
   -n             dry-run mode: do nothing, print what would have been done
+  -p PACKAGE     install additional package
   -q             quiet mode: suppress all messages, except errors
   -s SERIES      additionally install all packages from SERIES;
 		 incompatible with -a
@@ -240,7 +243,11 @@ function upgrade_package() {
     fi
 }
 
-while getopts "ahknq:s:vy" OPTION
+function version_gt() {
+    test "$(echo "$@" | tr " " "\n" | sort -V | head -n 1)" != "$1"
+}
+
+while getopts "ahknp:qs:vy" OPTION
 do
     case $OPTION in
 	a) install_all=y;;
@@ -248,6 +255,7 @@ do
 	   exit 0;;
 	k) keep_file=$OPTARG;;
 	n) dry_run=y;;
+	p) install_packages="$install_packages $OPTARG";;
 	q) verbosity=q;;
 	v) verbosity=v;;
 	s) install_series="$install_series $OPTARG";;
@@ -307,7 +315,7 @@ if [ -z "$rooturl" ]; then
 	rooturl="$mirrors_url/slackware$ARCH-$new_version"
 	error "info: using $rooturl as distribution top-level URL"
     else
-	error "no URL supplied"
+	abend "can't find distribution newer than $VERSION; please supply URL if you have any"
     fi
 fi    
 
@@ -395,7 +403,10 @@ fi
 for s in $install_series
 do
     series_package_names $s
-done) | sort -u  > candidates
+done
+if [ -n "$install_packages" ]; then
+    echo $install_packages
+fi) | sort -u  > candidates
 
 # Build a list of packages that should be removed after install
 remove_list=$logstem.removed
@@ -422,6 +433,14 @@ EOF
 cat $remove_list) | ${PAGER:-more}
 fi
 
+if ! version_gt $newversion $VERSION; then
+    if ! getyn n "Distribution version $newversion is same or lower than current version $VERSION. Downgrade"; then
+	tempdir_remove
+	echo Exiting
+	exit 0
+    fi
+fi
+
 if ! getyn n "Ready for upgrade from $VERSION to $newversion. Continue"; then
     tempdir_remove
     echo "Exiting"
diff --git a/slackware-upgrade-system.8 b/slackware-upgrade-system.8
index dbf35e4..08b5056 100644
--- a/slackware-upgrade-system.8
+++ b/slackware-upgrade-system.8
@@ -23,6 +23,7 @@ slackware\-upgrade\-system \- do a full upgrade of a Slackware installation
 \fBslackware\-upgrade\-system\fR\
  [\fB\-anqvy\fR]\
  [\fB\-k \fIFILE\fR]\
+ [\fB\-p \fIPACKAGE\fR\]
  [\fB\-s \fISERIES\fR]\
  [\fIURL\fR]
 .ad
@@ -134,6 +135,9 @@ as argument to that option.  This way all packages will be preserved.
 Dry-run mode: do nothing, print what would have been done.  In spite
 of the name, the list of packages for removal will still be created.
 .TP
+\fB\-p \fIPACKAGE\fR
+Install additional package.
+.TP
 .B \-q
 Quiet mode: suppress all messages, except error diagnostics.
 .TP
-- 
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