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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-06-03 13:54:25 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-06-03 13:54:25 +0000
commit9cb1c4df7b9ce1a9ad1312621b0f2b16a94fba3a (patch)
tree2efb72864cc69e174c9c5ee33efb88a5f1553b48 /modules.d/99img-lib
parentInitial commit. (diff)
downloaddracut-9cb1c4df7b9ce1a9ad1312621b0f2b16a94fba3a.tar.xz
dracut-9cb1c4df7b9ce1a9ad1312621b0f2b16a94fba3a.zip
Adding upstream version 060+5.upstream/060+5
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'modules.d/99img-lib')
-rwxr-xr-xmodules.d/99img-lib/img-lib.sh108
-rwxr-xr-xmodules.d/99img-lib/module-setup.sh21
2 files changed, 129 insertions, 0 deletions
diff --git a/modules.d/99img-lib/img-lib.sh b/modules.d/99img-lib/img-lib.sh
new file mode 100755
index 0000000..4700832
--- /dev/null
+++ b/modules.d/99img-lib/img-lib.sh
@@ -0,0 +1,108 @@
+#!/bin/sh
+# img-lib.sh: utilities for dealing with archives and filesystem images.
+#
+# TODO: identify/unpack rpm, deb, maybe others?
+
+# super-simple "file" that only identifies archives.
+# works with stdin if $1 is not set.
+det_archive() {
+ # NOTE: internal echo -e works in ash and bash, but not dash
+ local bz xz gz zs
+ local headerblock
+ bz="BZh"
+ # shellcheck disable=SC3037
+ xz="$(/bin/echo -e '\xfd7zXZ')"
+ # shellcheck disable=SC3037
+ gz="$(/bin/echo -e '\x1f\x8b')"
+ # shellcheck disable=SC3037
+ zs="$(/bin/echo -e '\x28\xB5\x2F\xFD')"
+ headerblock="$(dd ${1:+if=$1} bs=262 count=1 2> /dev/null | tr -d '\0')"
+ case "$headerblock" in
+ $xz*) echo "xz" ;;
+ $gz*) echo "gzip" ;;
+ $bz*) echo "bzip2" ;;
+ $zs*) echo "zstd" ;;
+ 07070*) echo "cpio" ;;
+ *ustar) echo "tar" ;;
+ esac
+}
+
+# determine filesystem type for a filesystem image
+det_fs_img() {
+ local dev
+ dev=$(losetup --find --show "$1") rv=""
+ det_fs "$dev"
+ rv=$?
+ losetup -d "$dev"
+ return $rv
+}
+
+# unpack_archive ARCHIVE OUTDIR
+# unpack a (possibly compressed) cpio/tar archive
+unpack_archive() {
+ local img="$1" outdir="$2" archiver="" decompr=""
+ local ft
+ ft="$(det_archive "$img")"
+ case "$ft" in
+ xz | gzip | bzip2 | zstd) decompr="$ft -dc" ;;
+ cpio | tar) decompr="cat" ;;
+ *) return 1 ;;
+ esac
+ ft="$($decompr "$img" | det_archive)"
+ case "$ft" in
+ cpio) archiver="cpio -iumd" ;;
+ tar) archiver="tar -xf -" ;;
+ *) return 2 ;;
+ esac
+ mkdir -p "$outdir"
+ (
+ cd "$outdir" || exit
+ $decompr | $archiver 2> /dev/null
+ ) < "$img"
+}
+
+# unpack_fs FSIMAGE OUTDIR
+# unpack a filesystem image
+unpack_fs() {
+ local img="$1" outdir="$2"
+ local mnt
+ mnt="$(mkuniqdir /tmp unpack_fs.)"
+ mount -o loop "$img" "$mnt" || {
+ rmdir "$mnt"
+ return 1
+ }
+ mkdir -p "$outdir"
+ outdir="$(
+ cd "$outdir" || exit
+ pwd
+ )"
+ copytree "$mnt" "$outdir"
+ umount "$mnt"
+ rmdir "$mnt"
+}
+
+# unpack an image file - compressed/uncompressed cpio/tar, filesystem, whatever
+# unpack_img IMAGEFILE OUTDIR
+unpack_img() {
+ local img="$1" outdir="$2"
+ [ -r "$img" ] || {
+ warn "can't read img!"
+ return 1
+ }
+ [ -n "$outdir" ] || {
+ warn "unpack_img: no output dir given"
+ return 1
+ }
+
+ if [ "$(det_archive "$img")" ]; then
+ unpack_archive "$@" || {
+ warn "can't unpack archive file!"
+ return 1
+ }
+ else
+ unpack_fs "$@" || {
+ warn "can't unpack filesystem image!"
+ return 1
+ }
+ fi
+}
diff --git a/modules.d/99img-lib/module-setup.sh b/modules.d/99img-lib/module-setup.sh
new file mode 100755
index 0000000..4f57b37
--- /dev/null
+++ b/modules.d/99img-lib/module-setup.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+# module-setup for img-lib
+
+# called by dracut
+check() {
+ require_binaries tar gzip dd echo tr || return 1
+ return 255
+}
+
+# called by dracut
+depends() {
+ return 0
+}
+
+# called by dracut
+install() {
+ inst_multiple tar gzip dd echo tr rmdir
+ # TODO: make this conditional on a cmdline flag / config option
+ inst_multiple -o cpio xz bzip2 zstd
+ inst_simple "$moddir/img-lib.sh" "/lib/img-lib.sh"
+}