img2fwup

#!/bin/sh

set -e

IMGFILE=$1
FWFILE=$2

if [ -z "$IMGFILE" ]; then
    echo "Compress an image file into a .fw archive so that it can be written to a"
    echo "MicroSD card using fwup."
    echo
    echo "Usage: img2fwup <imgfile> [output .fw file]"
    exit 1
fi

if [ -z "$FWFILE" ]; then
    FWFILE=${IMGFILE%.img}.fw
fi

echo "Compressing '$IMGFILE' to '$FWFILE'..."

fwup -c -o "$FWFILE" -f - <<EOF
meta-product = ""
meta-description = "$(basename "$IMGFILE")"
meta-version = ""
meta-platform = ""
meta-architecture = ""
meta-author = "$USER"
file-resource img {
        host-path = "${IMGFILE}"
        skip-holes = false  # This optimization isn't safe for all .img files
}
define-eval(IMG_BLOCKS, "(\${FWUP_SIZE_img} + 511) / 512")
task complete {
    on-resource img {
        trim(0, \${IMG_BLOCKS})
        raw_write(0)
    }
}
EOF

echo "Done."