iso.conf: better explaining comments

bin/iso/buildiso.in

@@ -332,7 +332,7 @@ usage() {
     echo '    -i <name>          Init system to use'
     echo "                       [default: ${INITSYS}]"
     echo '    -g <key>           The gpg key for img signing'
-    echo "                       [default: ${GPG_KEY}]"
+    echo "                       [default: none]"
     echo '    -m                 Set SquashFS image mode to persistence'
     echo '    -c                 Disable clean work dir'
     echo '    -x                 Build chroot only'

data/conf/artools-iso.conf

@@ -13,3 +13,8 @@
 
 # gpg key; leave empty or commented to skip img signing
 # GPG_KEY=""
+
+# mksquashfs compression
+# default: zstd <compression-level> should be 1 .. 22 (default 15)
+# optional xz args: COMPRESSION_ARGS=(-comp xz -Xbcj x86)
+#COMPRESSION_ARGS=(-comp zstd -Xcompression-level 22)

lib/iso/initcpio.sh

@@ -5,13 +5,17 @@
 make_checksum(){
     local file="$1"
     msg2 "Creating md5sum ..."
+    cd "${iso_root}${live_dir}"
     md5sum "$file" > "$file".md5
+    cd "${OLDPWD}"
 }
 
 make_sig () {
     local file="$1"
     msg2 "Creating signature file..."
+    chown "${owner}:$(id --group "${owner}")" "${iso_root}${live_dir}"
     su "${owner}" -c "gpg --detach-sign --output $file.sig --default-key ${GPG_KEY} $file"
+    chown "root:root" "${iso_root}${live_dir}"
 }
 
 export_gpg_publickey() {

lib/iso/squash.sh

@@ -67,16 +67,14 @@ make_sfs() {
 
         mksfs_args+=("${sfs_out}")
 
-        mksfs_args+=(-comp zstd -noappend)
+        mksfs_args+=("${COMPRESSION_ARGS[@]}" -noappend)
 
         mksquashfs "${mksfs_args[@]}"
 
         if ! ${use_dracut}; then
-            make_checksum "${iso_root}${live_dir}/${img_name}"
+            make_checksum "${img_name}"
             if [[ -n ${GPG_KEY} ]];then
-                chown "${owner}:$(id --group "${owner}")" "${iso_root}${live_dir}"
                 make_sig "${iso_root}${live_dir}/${img_name}"
-                chown "root:root" "${iso_root}${live_dir}"
             fi
         fi
         if ${persist}; then

lib/util-iso.sh

@@ -19,6 +19,10 @@ load_iso_config(){
 
     GPG_KEY=${GPG_KEY:-''}
 
+    if [[ -z "${COMPRESSION_ARGS[*]}" ]]; then
+        COMPRESSION_ARGS=(-comp zstd -Xcompression-level 22)
+    fi
+
     return 0
 }