mkimage2

#!/bin/bash

## hyphop ##

#= mkimage wrapper
#= zero time recalc crc32

## EXAMPLE

#  mkimage  -C none -A arm -T script -d INPUT OUTPUT && file OUTPUT
#./mkimage2 -C none -A arm -T script -d INPUT OUTPUT && file OUTPUT

[ "$1" = "-t" ] && {
    echo "[i] TEST">&2
    T=/tmp/mkimage2.test
    printf "1234" > $T
    $0 -C none -A arm -T script -d $T $T.out && \
	file $T.out || grep 0xFA265D13 && echo "[i] OK"
    rm $T $T.out
    exit 0
}

OUT=
for v in $@; do
    OUT=$v
done

echo "[i] MKIMAGE OUT: $OUT">&2

mkimage $@ || exit 1

## replace crc32 and time
dd if=/dev/zero bs=4 seek=1 count=2 conv=fsync,notrunc of=$OUT 2>/dev/null
#
[ "$V" ] && {
## gzip + HEXDUMP + bash (or busybox ash )
CRC=$(dd if=$OUT bs=64 count=1 2>/dev/null | gzip -1 -c | tail -c8 | hexdump -n4 -e '"%X"')
h1=${CRC:6:2}
h2=${CRC:4:2}
h3=${CRC:2:2}
h4=${CRC:0:2}
#echo "[i] MKIMAGE CRC $CRC == $h1$h2$h3$h4">&2
printf "%b" "\x$h4\x$h3\x$h2\x$h1" | dd bs=4 seek=1 count=1 conv=fsync,notrunc of=$OUT 2>/dev/null
}

[ "$V" ] || {
## gzip + dd only
T=/tmp/crc32.bin
dd if=$OUT bs=64 count=1 2>/dev/null | \
    gzip -1 -c | tail -c8 | head -c4 > $T
#    echo "[i] crc32 $(hexdump -n4 -e '"%X"' $T)"
    (
	dd if=$T bs=1 skip=3 count=1 2>/dev/null
	dd if=$T bs=1 skip=2 count=1 2>/dev/null
	dd if=$T bs=1 skip=1 count=1 2>/dev/null
	dd if=$T bs=1 skip=0 count=1 2>/dev/null
    ) > $T.rev

    dd bs=4 seek=1 count=1 conv=fsync,notrunc of=$OUT 2>/dev/null < $T.rev
    rm $T $T.rev
}

exit 0

#64=32+32 - HEADER SIZE for CRC32

#typedef struct image_header {
#    uint32_t	ih_magic;	/* Image Header Magic Number	*/
#    uint32_t	ih_hcrc;	/* Image Header CRC Checksum	*/
#    uint32_t	ih_time;	/* Image Creation Timestamp	*/
#    uint32_t	ih_size;	/* Image Data Size		*/
#    uint32_t	ih_load;	/* Data	 Load  Address		*/
#    uint32_t	ih_ep;		/* Entry Point Address		*/
#    uint32_t	ih_dcrc;	/* Image Data CRC Checksum	*/
#    uint8_t		ih_os;		/* Operating System		*/
#    uint8_t		ih_arch;	/* CPU architecture		*/
#    uint8_t		ih_type;	/* Image Type			*/
#    uint8_t		ih_comp;	/* Compression Type		*/
#    uint8_t		ih_name[IH_NMLEN];	/* Image Name		*/
#} image_header_t;