[OE-core] [v2 PATCH 1/7] bootimage.bbclass: Move fat image creation into a function

[Darren Hart]

On Fri, 2013-09-13 at 19:08 -0500, Jason Wessel wrote:
> In order to call the fat image creation multiple times it needs to be
> in its own function.  A future commit will make use of the new
> function to additionally create EFI image files for use with an ISO.
> 
> [YOCTO #4100]
> [YOCTO #1913]
> 
> Signed-off-by: Jason Wessel <jason.wessel at windriver.com>

Looks good, thanks Jason!

Reviewed-by: Darren Hart <dvhart at linux.intel.com>

> ---
>  meta/classes/bootimg.bbclass |  110 ++++++++++++++++++++++--------------------
>  1 file changed, 58 insertions(+), 52 deletions(-)
> 
> diff --git a/meta/classes/bootimg.bbclass b/meta/classes/bootimg.bbclass
> index 90a241d..bd211fb 100644
> --- a/meta/classes/bootimg.bbclass
> +++ b/meta/classes/bootimg.bbclass
> @@ -111,6 +111,63 @@ build_iso() {
>  	ln -s ${IMAGE_NAME}.iso ${DEPLOY_DIR_IMAGE}/${IMAGE_LINK_NAME}.iso
>  }
>  
> +build_fat_img() {
> +	FATSOURCEDIR=$1
> +	FATIMG=$2
> +
> +	# Calculate the size required for the final image including the
> +	# data and filesystem overhead.
> +	# Sectors: 512 bytes
> +	#  Blocks: 1024 bytes
> +
> +	# Determine the sector count just for the data
> +	SECTORS=$(expr $(du --apparent-size -ks ${FATSOURCEDIR} | cut -f 1) \* 2)
> +
> +	# Account for the filesystem overhead. This includes directory
> +	# entries in the clusters as well as the FAT itself.
> +	# Assumptions:
> +	#   FAT32 (12 or 16 may be selected by mkdosfs, but the extra
> +	#   padding will be minimal on those smaller images and not
> +	#   worth the logic here to caclulate the smaller FAT sizes)
> +	#   < 16 entries per directory
> +	#   8.3 filenames only
> +
> +	# 32 bytes per dir entry
> +	DIR_BYTES=$(expr $(find ${FATSOURCEDIR} | tail -n +2 | wc -l) \* 32)
> +	# 32 bytes for every end-of-directory dir entry
> +	DIR_BYTES=$(expr $DIR_BYTES + $(expr $(find ${FATSOURCEDIR} -type d | tail -n +2 | wc -l) \* 32))
> +	# 4 bytes per FAT entry per sector of data
> +	FAT_BYTES=$(expr $SECTORS \* 4)
> +	# 4 bytes per FAT entry per end-of-cluster list
> +	FAT_BYTES=$(expr $FAT_BYTES + $(expr $(find ${FATSOURCEDIR} -type d | tail -n +2 | wc -l) \* 4))
> +
> +	# Use a ceiling function to determine FS overhead in sectors
> +	DIR_SECTORS=$(expr $(expr $DIR_BYTES + 511) / 512)
> +	# There are two FATs on the image
> +	FAT_SECTORS=$(expr $(expr $(expr $FAT_BYTES + 511) / 512) \* 2)
> +	SECTORS=$(expr $SECTORS + $(expr $DIR_SECTORS + $FAT_SECTORS))
> +
> +	# Determine the final size in blocks accounting for some padding
> +	BLOCKS=$(expr $(expr $SECTORS / 2) + ${BOOTIMG_EXTRA_SPACE})
> +
> +	# Ensure total sectors is an integral number of sectors per
> +	# track or mcopy will complain. Sectors are 512 bytes, and we
> +	# generate images with 32 sectors per track. This calculation is
> +	# done in blocks, thus the mod by 16 instead of 32.
> +	BLOCKS=$(expr $BLOCKS + $(expr 16 - $(expr $BLOCKS % 16)))
> +
> +	# mkdosfs will sometimes use FAT16 when it is not appropriate,
> +	# resulting in a boot failure from SYSLINUX. Use FAT32 for
> +	# images larger than 512MB, otherwise let mkdosfs decide.
> +	if [ $(expr $BLOCKS / 1024) -gt 512 ]; then
> +		FATSIZE="-F 32"
> +	fi
> +
> +	mkdosfs ${FATSIZE} -n ${BOOTIMG_VOLUME_ID} -S 512 -C ${FATIMG} ${BLOCKS}
> +	# Copy FATSOURCEDIR recursively into the image file directly
> +	mcopy -i ${FATIMG} -s ${FATSOURCEDIR}/* ::/
> +}
> +
>  build_hddimg() {
>  	# Create an HDD image
>  	if [ "${NOHDD}" != "1" ] ; then
> @@ -123,58 +180,7 @@ build_hddimg() {
>  			grubefi_hddimg_populate
>  		fi
>  
> -		# Calculate the size required for the final image including the
> -		# data and filesystem overhead.
> -		# Sectors: 512 bytes
> -		#  Blocks: 1024 bytes
> -
> -		# Determine the sector count just for the data
> -		SECTORS=$(expr $(du --apparent-size -ks ${HDDDIR} | cut -f 1) \* 2)
> -
> -		# Account for the filesystem overhead. This includes directory
> -		# entries in the clusters as well as the FAT itself.
> -		# Assumptions:
> -		#   FAT32 (12 or 16 may be selected by mkdosfs, but the extra
> -		#   padding will be minimal on those smaller images and not
> -		#   worth the logic here to caclulate the smaller FAT sizes)
> -		#   < 16 entries per directory
> -		#   8.3 filenames only
> -
> -		# 32 bytes per dir entry
> -		DIR_BYTES=$(expr $(find ${HDDDIR} | tail -n +2 | wc -l) \* 32)
> -		# 32 bytes for every end-of-directory dir entry
> -		DIR_BYTES=$(expr $DIR_BYTES + $(expr $(find ${HDDDIR} -type d | tail -n +2 | wc -l) \* 32))
> -		# 4 bytes per FAT entry per sector of data
> -		FAT_BYTES=$(expr $SECTORS \* 4)
> -		# 4 bytes per FAT entry per end-of-cluster list
> -		FAT_BYTES=$(expr $FAT_BYTES + $(expr $(find ${HDDDIR} -type d | tail -n +2 | wc -l) \* 4))
> -
> -		# Use a ceiling function to determine FS overhead in sectors
> -		DIR_SECTORS=$(expr $(expr $DIR_BYTES + 511) / 512)
> -		# There are two FATs on the image
> -		FAT_SECTORS=$(expr $(expr $(expr $FAT_BYTES + 511) / 512) \* 2)
> -		SECTORS=$(expr $SECTORS + $(expr $DIR_SECTORS + $FAT_SECTORS))
> -
> -		# Determine the final size in blocks accounting for some padding
> -		BLOCKS=$(expr $(expr $SECTORS / 2) + ${BOOTIMG_EXTRA_SPACE})
> -
> -		# Ensure total sectors is an integral number of sectors per
> -		# track or mcopy will complain. Sectors are 512 bytes, and we
> -		# generate images with 32 sectors per track. This calculation is
> -		# done in blocks, thus the mod by 16 instead of 32.
> -		BLOCKS=$(expr $BLOCKS + $(expr 16 - $(expr $BLOCKS % 16)))
> -
> -		# mkdosfs will sometimes use FAT16 when it is not appropriate,
> -		# resulting in a boot failure from SYSLINUX. Use FAT32 for
> -		# images larger than 512MB, otherwise let mkdosfs decide.
> -		if [ $(expr $BLOCKS / 1024) -gt 512 ]; then
> -			FATSIZE="-F 32"
> -		fi
> -
> -		IMG=${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.hddimg
> -		mkdosfs ${FATSIZE} -n ${BOOTIMG_VOLUME_ID} -S 512 -C ${IMG} ${BLOCKS}
> -		# Copy HDDDIR recursively into the image file directly
> -		mcopy -i ${IMG} -s ${HDDDIR}/* ::/
> +		build_fat_img ${HDDDIR} ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.hddimg
>  
>  		if [ "${PCBIOS}" = "1" ]; then
>  			syslinux_hddimg_install

-- 
Darren Hart
Intel Open Source Technology Center
Yocto Project - Linux Kernel