bootimage.bbclass: Move fat image creation into a function

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]

(From OE-Core rev: 6d5181dc68766f42416a41f4988e8400d37fd7fa)

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

1 files changed, 58 insertions, 52 deletions

diff --git a/meta/classes/bootimg.bbclass b/meta/classes/bootimg.bbclass
index 90a241d9b3..bd211fbdc3 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