[isar-cip-core] RFC v2 1/9] Add new class to create a squashfs based root file system

Commit Message

Quirin Gylstorff Nov. 16, 2021, 11:27 a.m. UTC

From: Quirin Gylstorff <[e-mail]>

This file system is read only and use a reduced image size.

Signed-off-by: Quirin Gylstorff <[e-mail]>
---
 classes/squashfs-img.bbclass | 41 ++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)
 create mode 100644 classes/squashfs-img.bbclass

Patch

diff --git a/classes/squashfs-img.bbclass b/classes/squashfs-img.bbclass
new file mode 100644
index 0000000..0fcfca5
--- /dev/null
+++ b/classes/squashfs-img.bbclass
@@ -0,0 +1,41 @@ 
+#
+# CIP Core, generic profile
+#
+# Copyright (c) Siemens AG, 2021
+#
+# Authors:
+#  Quirin Gylstorff <[e-mail]>
+#
+# SPDX-License-Identifier: MIT
+#
+
+SQUASHFS_IMAGE_FILE = "${IMAGE_FULLNAME}.squashfs.img"
+
+IMAGER_INSTALL += "squashfs-tools"
+
+SQUASHFS_EXCLUDE_DIRS ?= ""
+SQUASHFS_CONTENT ?= "${PP_ROOTFS}"
+SQUASHFS_CREATION_ARGS ?= " "
+# Generate squashfs filesystem image
+python __anonymous() {
+    exclude_directories = (d.getVar('SQUASHFS_EXCLUDE_DIRS') or "").split()
+    if len(exclude_directories) == 0:
+        return
+    # use wildcard to exclude only content of the the directory
+    # this allows to use the directory as a mount point
+    args = " -wildcards"
+    for dir in exclude_directories:
+        args += " -e {dir}/* ".format(dir=dir)
+    d.appendVar('SQUASHFS_CREATION_ARGS', args)
+}
+
+do_squashfs_image() {
+    rm -f '${DEPLOY_DIR_IMAGE}/${SQUASHFS_IMAGE_FILE}'
+
+    image_do_mounts
+
+    sudo chroot "${BUILDCHROOT_DIR}" /bin/mksquashfs  \
+        "${SQUASHFS_CONTENT}" "${PP_DEPLOY}/${SQUASHFS_IMAGE_FILE}" \
+        ${SQUASHFS_CREATION_ARGS}
+}
+addtask do_squashfs_image before do_image after do_image_tools do_excl_directories