# Extracts gzip files compressed with the deflate algorithm (i.e. all modern
# gzip files)
# Depends on gzip: http://www.gzip.org/

# Format defined at http://www.faqs.org/rfcs/rfc1952.html
# First byte: magic 0x1f
0 char \x1f
# The next 4 bytes: magic 0x8b, compression method 0x08 (deflate), flags (bits
# 5, 6 and 7 are reserved), first byte of mtime (little endian?!)
1 int32 8B080000 FFffE000
# Last byte of mtime (assuming before year 2038), "Extra flags" (only the
# values 2 and 4 are used by deflate)
7 int32 00000000 80F90000
extension unzipped

# Allow infinite overlap because the expanded file may be much larger than the
# compressed one.
allow_overlap -1

command gzip -d > "$1"
rename gzip_rename.pl "$1"