bootimage.bbclass, zisofs-tools-native: add ability to compress ISO images

The mkzftree is needed to allow ISO images to be compressed with
minimal runtime overhead.  Below is an example of the savings on a
core-image-minimal.

Before ls -l:
24117248 core-image-minimal-qemux86-64.iso

Using the mkzftree ls -l:
16777216 core-image-minimal-qemux86-64.iso

(From OE-Core rev: 808d4371939ec48ed62e0c0b6614b96d61b1f7b8)

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 21 insertions, 3 deletions

diff --git a/meta/classes/bootimg.bbclass b/meta/classes/bootimg.bbclass
index fdd4ea9561..c61c4e985e 100644
--- a/meta/classes/bootimg.bbclass
+++ b/meta/classes/bootimg.bbclass
@@ -19,13 +19,15 @@
 
 # External variables (also used by syslinux.bbclass)
 # ${INITRD} - indicates a filesystem image to use as an initrd (optional)
+# ${COMPRESSISO} - Transparent compress ISO, reduce size ~40% if set to 1
 # ${NOISO}  - skip building the ISO image if set to 1
 # ${NOHDD}  - skip building the HDD image if set to 1
 # ${ROOTFS} - indicates a filesystem image to include as the root filesystem (optional)
 
 do_bootimg[depends] += "dosfstools-native:do_populate_sysroot \
                         mtools-native:do_populate_sysroot \
-                        cdrtools-native:do_populate_sysroot"
+                        cdrtools-native:do_populate_sysroot \
+                        ${@oe.utils.ifelse(d.getVar('COMPRESSISO'),'zisofs-tools-native:do_populate_sysroot','')}"
 
 PACKAGES = " "
 EXCLUDE_FROM_WORLD = "1"
@@ -33,6 +35,8 @@ EXCLUDE_FROM_WORLD = "1"
 HDDDIR = "${S}/hddimg"
 ISODIR = "${S}/iso"
 EFIIMGDIR = "${S}/efi_img"
+COMPACT_ISODIR = "${S}/iso.z"
+COMPRESSISO ?= "0"
 
 BOOTIMG_VOLUME_ID   ?= "boot"
 BOOTIMG_EXTRA_SPACE ?= "512"
@@ -97,18 +101,32 @@ build_iso() {
                 install -m 0644 ${STAGING_DATADIR}/syslinux/isolinux.bin ${ISODIR}${ISOLINUXDIR}
         fi
 
+        if [ "${COMPRESSISO}" = "1" ] ; then
+                # create compact directory, compress iso
+                mkdir -p ${COMPACT_ISODIR}
+                mkzftree -z 9 -p 4 -F ${ISODIR}/rootfs.img ${COMPACT_ISODIR}/rootfs.img
+
+                # move compact iso to iso, then remove compact directory
+                mv ${COMPACT_ISODIR}/rootfs.img ${ISODIR}/rootfs.img
+                rm -Rf ${COMPACT_ISODIR}
+                mkisofs_compress_opts="-R -z -D -l"
+        else
+                mkisofs_compress_opts="-r"
+        fi
+
         if [ "${PCBIOS}" = "1" ] && [ "${EFI}" != "1" ] ; then
                 # PCBIOS only media
                 mkisofs -V ${BOOTIMG_VOLUME_ID} \
                         -o ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.iso \
-                        -b ${ISO_BOOTIMG} -c ${ISO_BOOTCAT} -r \
+                        -b ${ISO_BOOTIMG} -c ${ISO_BOOTCAT} \
+                        $mkisofs_compress_opts \
                         ${MKISOFS_OPTIONS} ${ISODIR}
         else
                 # EFI only OR EFI+PCBIOS
                 mkisofs -A ${BOOTIMG_VOLUME_ID} -V ${BOOTIMG_VOLUME_ID} \
                         -o ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.iso \
                         -b ${ISO_BOOTIMG} -c ${ISO_BOOTCAT} \
-                        -r ${MKISOFS_OPTIONS} \
+                        $mkisofs_compress_opts ${MKISOFS_OPTIONS} \
                         -eltorito-alt-boot -eltorito-platform efi \
                         -b efi.img -no-emul-boot \
                         ${ISODIR}