From ade1758e22af33aa3b69261e8242bb68ff4bdb35 Mon Sep 17 00:00:00 2001
From: Eric Renfro <psi-jack@linux-help.org>
Date: Sat, 3 Aug 2024 14:25:13 -0400
Subject: [PATCH] Refactor exstate4 massively and cleanup

---
 exstage4.sh | 171 +++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 155 insertions(+), 16 deletions(-)

diff --git a/exstage4.sh b/exstage4.sh
index 7756a2a..ddef088 100755
--- a/exstage4.sh
+++ b/exstage4.sh
@@ -1,24 +1,163 @@
 #!/usr/bin/env bash
 
-STAGE_FILE=${1}
+# get available compression types
+declare -A compressTypes
+compressTypes=(
+	["bz2"]="bzip2 pbzip2 lbzip2"
+	["gz"]="gzip pigz"
+	["lrz"]="lrzip"
+	["lz"]="lzip plzip"
+	["lz4"]="lz4"
+	["lzo"]="lzop"
+	["xz"]="xz pixz"
+	["zst"]="zstd"
+)
+declare -A compressAvail
+for ext in "${!compressTypes[@]}"; do
+	for exechk in ${compressTypes[${ext}]}; do
+		binchk=$(command -v "${exechk}")
+		if [[ -n "$binchk" ]]; then
+			compressAvail+=(["${ext}"]="$binchk")
+		fi
+	done
+done
 
-EXT="${STAGE_FILE##*.}"
+# set flag variables to null/default
+optQuiet=false
 
-TARFILE="${STAGE_FILE%%.$EXT}"
-TAREXT="${TARFILE##*.}"
 
-if [[ $TAREXT != "tar" ]]; then
-	echo "The stage file you are trying to unpack (\`$STAGE_FILE\`) does not appear to be an archived TAR file"
-else
-	echo "Extracting \`${STAGE_FILE}\` inplace."
+function showHelp() {
+	echo "Usage:"
+	echo "$(basename "$0") [-q ] [-s || -t <target>] <archivename> [-- [additional-tar-options]]"
+	echo 
+	echo "-q           activates quiet mode (no confirmation)"
+	echo "-s           extracts archive in current directory"
+	echo "-t <path>    extracts archive in target <path>"
+	echo "-h           display this help message."
+
+	if [[ "$1" -ge 0 ]]; 	then
+		exit "$1"
+	else
+		exit 0
+	fi
+}
+
+function errorMsg() {
+	local rc=0
+
+	if [[ "$1" -gt 0 ]]; then
+		rc="$1"
+		shift
+	fi
+
+	echo "$*" >&2
+
+	if [[ "$rc" -gt 0 ]]; then
+		exit "$rc"
+	fi
+}
+
+
+# reads options:
+tarArgs=()
+while [[ $# -gt 0 ]]; do
+	while getopts ":t:sqh" flag; do
+		case "$flag" in
+			t)	targetPath="$OPTARG";;
+			s)	targetPath="$(pwd)";;
+			q)	optQuiet=true;;
+			h)	showHelp 0;;
+			\?)	errorMsg 1 "Invalid option: -$OPTARG";;
+			:)	errorMsg 1 "Option -$OPTARG requires an argument.";;
+		esac
+	done || exit 1
+
+	[[ $OPTIND -gt $# ]] && break # reached the end of parameters
+
+	shift $((OPTIND - 1)) # Free processed options so far
+	OPTIND=1              # we must reset OPTIND
+	if [[ -z "$archiveFile" ]]; then
+		archiveFile=$1
+	else
+		tarArgs[${#tarArgs[*]}]=$1
+	fi
+	shift                 # remove saved arg
+done
+
+# checks if run as root:
+#if [[ "$(id -u)" -ne 0 ]]; then
+#	echo "$(basename "$0"): must run as root"
+#	exit 250
+#fi
+
+if [[ ! -r "$archiveFile" ]]; then
+	echo "ERROR: archive file (\`$archiveFile\`) does not exist"
+	exit 1
 fi
 
-if [ "$EXT" == "xz" ]; then
-	tar -I 'xz -T0' -xvf "${STAGE_FILE}" --xattrs-include='*.*' --numeric-owner
-elif [ "$EXT" == "bz2" ]; then
-	tar -I pbzip2 -xvf "${STAGE_FILE}" --xattrs-include='*.*' --numeric-owner
-elif [ "$EXT" == "gz" ]; then
-	tar -I unpigz -xvf "${STAGE_FILE}" --xattrs-include='*.*' --numeric-owner
-else
-	echo "Not sure how to unpack \`${STAGE_FILE}\`"
+archiveExt="${archiveFile##*.}"
+
+if [[ "${archiveFile%%.$archiveExt}" =~ *.\.tar ]]; then
+	echo "The stage file you are trying to unpack (\`$archiveFile\`) does not appear to be an archived TAR file"
+	echo "${archiveFile%%.$archiveExt}"
+	exit 1
+fi
+
+if [[ -n "$targetPath" ]]; then
+	if [[ ! -d "$targetPath" ]]; then
+		echo "$(basename "$0"): target path '$targetPath' does not exist"
+		exit 1
+	fi
+
+	# make sure targetPath path ends with slash
+	if [[ "$targetPath" != */ ]]; then
+		targetPath="${targetPath}/"
+	fi
+else
+	echo "ERROR: Neither -s or -t <path> provided"
+	exit 2
+fi
+
+# Check if specified type is available
+if [[ -z "${compressAvail[$archiveExt]}" ]]; then
+	echo "$(basename "$0"): specified archive compression type not supported."
+	echo "Supported: ${compressAvail[*]}"
+	exit 1
+fi
+
+compressOptions=("${compressAvail[$archiveExt]}")
+case "$archiveExt" in
+	xz)		compressOptions+=("-T0");;
+esac
+
+tarOptions=(
+	"-xv"
+	"--xattrs-include=*.*"
+	"--numeric-owner"
+	"--use-compress-prog=${compressOptions[*]}"
+)
+
+tarOptions+=("${tarArgs[@]}")
+
+
+# if not in optQuiet mode, this message will be displayed:
+if ! $optQuiet; then
+	echo "Are you sure that you want to extract a stage archive to the system"
+	echo "to the destination path?"
+	echo "$targetPath"
+	echo
+	echo "COMMAND LINE PREVIEW:"
+	echo 'tar' "${tarOptions[@]}" -f "$archiveFile" -C "$targetPath"
+	echo
+	echo -n 'Type "yes" to continue or anything else to quit: '
+	read -r promptAgree
+	if [[ "${promptAgree,,}" == "yes" ]]; then
+		optQuiet=true
+	fi
+fi
+
+# start stage4 creation:
+if $optQuiet; then
+	echo "Would've worked"
+	#tar "${tarOptions[@]}" -f "$archiveFile" -C "$targetPath"
 fi