#!/bin/sh

[ "$1" = "-q" ] && quiet=true || quiet=false

set -e

SRC="https://pci-ids.ucw.cz/v2.2/pci.ids"

DEST=pci.ids

PCI_COMPRESSED_IDS=

GREP=grep

# if pci.ids is read-only (because the filesystem is read-only),

# then just skip this whole process.

if ! touch ${DEST} >/dev/null 2>&1 ; then

	${quiet} || echo "${DEST} is read-only, exiting." 1>&2

	exit 1

fi

if [ "$PCI_COMPRESSED_IDS" = 1 ] ; then

	DECOMP="cat"

	SRC="$SRC.gz"

	GREP=zgrep

elif which bzip2 >/dev/null 2>&1 ; then

	DECOMP="bzip2 -d"

	SRC="$SRC.bz2"

elif which gzip >/dev/null 2>&1 ; then

	DECOMP="gzip -d"

	SRC="$SRC.gz"

else

	DECOMP="cat"

fi

if which curl >/dev/null 2>&1 ; then

	DL="curl -o $DEST.new $SRC"

    ${quiet} && DL="$DL -s -S"

elif which wget >/dev/null 2>&1 ; then

	DL="wget --no-timestamping -O $DEST.new $SRC"

	${quiet} && DL="$DL -q"

elif which lynx >/dev/null 2>&1 ; then

	DL="eval lynx -source $SRC >$DEST.new"

else

	echo >&2 "update-pciids: cannot find curl, wget or lynx"

	exit 1

fi

if ! $DL ; then

	echo >&2 "update-pciids: download failed"

	rm -f $DEST.new

	exit 1

fi

if ! $DECOMP <$DEST.new >$DEST.neww ; then

	echo >&2 "update-pciids: decompression failed, probably truncated file"

	exit 1

fi

if ! $GREP >/dev/null "^C " $DEST.neww ; then

	echo >&2 "update-pciids: missing class info, probably truncated file"

	exit 1

fi

if [ -f $DEST ] ; then

	mv $DEST $DEST.old

	# --reference is supported only by chmod from GNU file, so let's ignore any errors

	chmod -f --reference=$DEST.old $DEST.neww 2>/dev/null || true

fi

mv $DEST.neww $DEST

rm $DEST.new

# Older versions did not compress the ids file, so let's make sure we

# clean that up.

if [ ${DEST%.gz} != ${DEST} ] ; then

	rm -f ${DEST%.gz} ${DEST%.gz}.old

fi

${quiet} || echo "Done."