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# TODO: Find git dir; global options
# TODO: LIBEXECDIR or something
GIT_DIR="${GIT_DIR:-.git}"
INDEX_VERSION=2
gitsort() (
# This will still often be wrong
LANG=C sort
)
# Is it hacky? Hell yes. Is it POSIX? HELL YES.
write_hex() {
hex="$1"
while [ -n "$hex" ]
do
cur=$(printf "%s" "$hex" | cut -c1-2)
next=$(printf "%s" "$hex" | cut -c3-)
printf "\\x$(printf "%s" "$cur")"
hex="$next"
done
}
# Prints an integer to stdout in binary, big-endian
write_int32() (
n="$1"
hex=$(printf "%08X" "$n")
write_hex "$hex"
)
write_int16() (
n="$1"
hex=$(printf "%04X" "$n")
write_hex "$hex"
)
read_text() (
path="$1"
offs="$2"
len="$3"
for oct in $(od -An -txC -N"$len" -j"$offs" "$index")
do
printf "\x$oct"
done
)
read_int16() (
path="$1"
offs="$2"
i16=$(od -An -tdS -j"$offs" -N2 "$path" | tr -d ' ')
i16=$((((i16>>8)&0xff) | ((i16<<8)&0xff00)))
echo "$i16"
)
read_int32() (
path="$1"
offs="$2"
i32=$(od -An -tdI -j"$offs" -N4 "$path" | tr -d ' ')
i32=$((((i32>>24)&0xff) |
((i32<<8)&0xff0000) |
((i32>>8)&0xff00) |
((i32<<24)&0xff000000)))
echo "$i32"
)
read_hex() (
path="$1"
offs="$2"
len="$3"
od -An -txC -N"$len" -j"$offs" "$path" | tr -d ' \n'
)
normalize_path() (
path="$1"
path="${path#./}"
# TODO: Remove the leading / if fully qualified
if [ "${path#.git}" != "$path" ]
then
printf '%s' 'Invalid path %s\n' "$path"
exit 1
fi
printf "%s" "$path"
)