Try to locate the next distribution automatically

2 files changed, 79 insertions, 50 deletions

diff --git a/slackware-upgrade-system b/slackware-upgrade-system
index bc55bca..89bb3fc 100644
--- a/slackware-upgrade-system
+++ b/slackware-upgrade-system
@@ -19,7 +19,7 @@
 set -e
 
 # Slackware root directory
-rootdir=/root/slackware
+rooturl=
 # Log file name
 logfile=
 # 'y', if dry-run mode is requested
@@ -112,11 +112,23 @@ function getyn() {
     fi
 }
 
+function error {
+    echo >&2 "$0: $*"
+    if [ -n "$logfile" ]; then
+	echo >$logfile "$0: $*"
+    fi
+}
+
+function abend {
+    error "$@"
+    tempdir_remove
+    exit 1
+}
+
 function package_file_name() {
     pkg=$(awk -vname=$1 '$1==name { print $2 }' $avail_index)
     if [ -z "$pkg" ]; then
-	echo >&2 "$0: package $name not found in index (should not happen!)"
-	echo >$logfile "$0: package $name not found in index (should not happen!)"
+	error "package $name not found in index (should not happen!)"
     else
         echo $pkg
     fi	    
@@ -131,11 +143,11 @@ function series_package_names() {
 }
 
 function catfile() {
-    echo $rootdir/${1#./}
+    echo $rooturl/${1#./}
 }
 
 function download_curl {
-    curl -sS -o$1 $2
+    curl -L -sS -o$1 $2
 }
 
 function download_wget {
@@ -145,6 +157,18 @@ function download_wget {
     fi
 }
 
+function dnfunc_init() {
+    if [ -z "$dnfunc" ]; then
+	if curl --version >/dev/null 2>&1; then
+	    dnfunc=download_curl
+	elif wget --version >/dev/null 2>&1; then
+	    dnfunc=download_wget
+	else
+	    abend "neither curl nor wget is installed"
+	fi
+    fi
+}
+
 function download() {
     local name=$(basename $1)
     local url=$(catfile $1)
@@ -154,7 +178,7 @@ function download() {
 		&& ${GPG:-gpg2} --verify $name.asc $name 2>/dev/null; then
 		:
 	    else
-		echo >&2 "$0: gpg verification failed for $name"
+		error "gpg verification failed for $name"
 	        return
             fi
 	fi
@@ -214,92 +238,95 @@ done
 shift $(($OPTIND - 1))
 case $# in
     0) ;;
-    1) rootdir=$1;;
-    *) echo >&2 "$0: unexpected arguments"
+    1) rooturl=$1;;
+    *) error "unexpected arguments"
        usage >&2
        exit 1
 esac
 
 if [ $(id -u) != "0" ]; then
-    echo >&2 "$0: must be root"
-    exit 1
+    abend "must be root"
 fi
 
 # Sanity check
 if [ ! -s /etc/os-release ]; then
-    echo >&2 "$0: /etc/os-release doesn't exist"
-    exit 1
+    abend "/etc/os-release doesn't exist"
 fi
 
 . /etc/os-release
 
 if [ "$ID" != "slackware" ]; then
-    echo >&2 "$0: this doesn't seem to be a Slackware installation"
-    exit 1
+    abend "this doesn't seem to be a Slackware installation"
 fi
 
 case "$(uname -m)" in
     i?86)   ARCH=;;
     x86_64) ARCH=64;;
-    *)      echo >&2 "$0: architecture $(uname -m) is not yet supported"
-	    exit
+    *)      abend "architecture $(uname -m) is not yet supported"
 esac
 
-# Check if rootdir is local or remote
-case $rootdir in
+tempdir_create
+cd $tempdir
+
+mirrors_url=https://mirrors.slackware.com/slackware
+if [ -z "$rooturl" ]; then
+    dnfunc_init
+    if ! $dnfunc index.html $mirrors_url; then
+	abend "exiting"
+	exit 1
+    fi
+    version_rx=$(echo $VERSION | sed -e 's/\./\\./g')
+    new_version=$(cat index.html |\
+      tr '<' '\n' |\
+      sed -n -r \
+	  -e 's/.*^a href="slackware'$ARCH'-([[:digit:].]+)\/?".*/\1/p'|\
+      sed -n -e "/$version_rx/{" -en -ep -e '}' )
+    if [ -n "$new_version" ]; then
+	rooturl="$mirrors_url/slackware$ARCH-$new_version"
+	error "info: using $rooturl as distribution top-level URL"
+    else
+	error "no URL supplied"
+    fi
+fi    
+
+# Check if rooturl is local or remote
+case $rooturl in
     /*) unset remote
 	;;
     http://*|https://*|ftp://*|ftps://*)
-	if curl --version >/dev/null 2>&1; then
-	    dnfunc=download_curl
-	elif wget --version >/dev/null 2>&1; then
-	    dnfunc=download_wget
-	else
-	    echo >&2 "$0: neither curl nor wget is installed"
-	    echo >&2 "$0: can't continue"
-	    exit 1
-	fi
+	dnfunc_init
 	remote=1
 	;;
-    *)  echo >&2 "$0: root directory must be absolute file name or URL"
-	exit 1
+    *)  abend "root directory must be absolute file name or URL"
 esac
 
 if [ -z "$remote" ]; then
-    # Check if rootdir exists and contains the necessary files and directories
-    if [ ! -d $rootdir ]; then
-	echo >&2 "$0: $rootdir does not exist"
-	exit 1
+    # Check if rooturl exists and contains the necessary files and directories
+    if [ ! -d $rooturl ]; then
+	abend "$rooturl does not exist"
     fi
 fi
 
-tempdir_create
-cd $tempdir
-
-# Check if rootdir contains all we need
+# Check if rooturl contains all we need
 checksums=$(getfile CHECKSUMS.md5)
 if [ -z "$checksums" ]; then
-    echo >&2 "$0: CHECKSUMS.md5 not found in $rootdir"
-    exit 1
+    abend "CHECKSUMS.md5 not found in $rooturl"
 fi
 
 announce=$(tail +13 $checksums | \
        sed -n -r\
            -e 's/^[0-9a-fA-F]+[[:space:]]+\.\/(ANNOUNCE\.[[:digit:]_]+)$/\1/p')
 if [ -z "$announce" ]; then
-    echo >&2 "$0: ANNOUNCE not found in $rootdir"
-    exit 1
+    abend "ANNOUNCE not found in $rooturl"
 fi    
 file=$(getfile $announce)
 if [ -z "$file" ]; then
-    echo >&2 "$0: file $announce not found in $rootdir"
-    exit 1
+    abend "file $announce not found in $rooturl"
 fi    
 
 newversion=$(echo "$announce" | sed -e 's/ANNOUNCE\.//' -e 's/_/./g')
 if [ -z "$newversion" ]; then
-    echo >&2 "$0: cannot determine new version"
-    exit 1
+    abend "cannot determine new version"
 fi
 
 # Create list and index of available files
@@ -318,13 +345,11 @@ for series in $series_names
 do
     n=$(sed -n -r -e 's/^[0-9a-fA-F]+[[:space:]]+(\.\/slackware(64)?\/l\/.*\.t.z)$/\1/p' $avail_index | head -1)
     if [ -z "$n" ]; then
-	echo >&2 "$0: no files in series $series"
-	exit 1
+	abend "no files in series $series"
     fi
     file=$(getfile $n)
     if [ -z "$file" ]; then
-	echo >&2 "$0: exiting"
-	exit
+	abend "exiting"
     fi
     dropfile $file
 done    
diff --git a/slackware-upgrade-system.8 b/slackware-upgrade-system.8
index 01bc25b..fcbdbda 100644
--- a/slackware-upgrade-system.8
+++ b/slackware-upgrade-system.8
@@ -31,7 +31,11 @@ slackware\-upgrade\-system \- do a full upgrade of a Slackware installation
 Upgrades the Slackware installation to a new release.  The \fIURL\fR
 argument supplies the URL of the Slackware distribution or the
 directory on the local filesystem where it can be found.  If not
-given, \fB/root/slackware\fR is assumed.
+given, the program will use the nearest next version distribution
+from
+.nh
+.BR https://mirrors.slackware.com .
+.hy
 .PP
 When started, the program first verifies that it runs with root
 privileges on a Slackware installation and determines the current