xz/src/scripts/xzgrep.in

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#!@POSIX_SHELL@
# SPDX-License-Identifier: GPL-2.0-or-later
# xzgrep -- a wrapper around a grep program that decompresses files as needed
# Adapted from a version sent by Charles Levert <charles@comm.polymtl.ca>
# Copyright (C) 1998, 2001, 2002, 2006, 2007 Free Software Foundation
# Copyright (C) 1993 Jean-loup Gailly
# Modified for XZ Utils by Andrew Dudman and Lasse Collin.
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
@enable_path_for_scripts@
#SET_PATH - This line is a placeholder to ease patching this script.
# Instead of unsetting XZ_OPT, just make sure that xz will use file format
# autodetection. This way memory usage limit and thread limit can be
# specified via XZ_OPT. With gzip, bzip2, and lzop it's OK to just unset the
# environment variables.
xz='@xz@ --format=auto'
unset GZIP BZIP BZIP2 LZOP
case ${0##*/} in
*egrep*) prog=xzegrep; grep=${GREP:-grep -E};;
*fgrep*) prog=xzfgrep; grep=${GREP:-grep -F};;
*) prog=xzgrep; grep=${GREP:-grep};;
esac
version="$prog (@PACKAGE_NAME@) @PACKAGE_VERSION@"
usage="Usage: ${0##*/} [OPTION]... [-e] PATTERN [FILE]...
Look for instances of PATTERN in the input FILEs, using their
uncompressed contents if they are compressed.
OPTIONs are the same as for '$grep'.
Report bugs to <@PACKAGE_BUGREPORT@>."
# sed script to escape all ' for the shell, and then (to handle trailing
# newlines correctly) turn trailing X on last line into '.
escape='
s/'\''/'\''\\'\'''\''/g
$s/X$/'\''/
'
operands=
have_pat=0
files_with_matches=0
files_without_matches=0
no_filename=0
with_filename=0
# See if -H and --label options are supported (GNU and *BSDs).
if test f:x = "$(eval "echo x | $grep -H --label=f x 2> /dev/null")"; then
grep_supports_label=1
else
grep_supports_label=0
fi
while test $# -ne 0; do
option=$1
shift
optarg=
case $option in
(-[0123456789abcdEFGhHiIKlLnoPqrRsTuUvVwxyzZ]*[!0123456789]*)
# Something like -Fiv was specified, that is, $option contains more
# than one option of which the first option (in this example -F)
# doesn't take an argument. Split the first option into a standalone
# argument and continue parsing the rest of the options (in this example,
# replace -Fiv with -iv in the argument list and set option=-F).
#
# If there are digits [0-9] they are treated as if they were a single
# option character because this syntax is an alias for -C for GNU grep.
# For example, "grep -25F" is equivalent to "grep -C25 -F". If only
# digits are specified like "grep -25" we don't get here because the
# above pattern in the case-statement doesn't match such strings.
arg2=-\'$(LC_ALL=C expr "X${option}X" : 'X-.[0-9]*\(.*\)' |
LC_ALL=C sed "$escape")
eval "set -- $arg2 "'${1+"$@"}'
option=$(LC_ALL=C expr "X$option" : 'X\(-.[0-9]*\)');;
(--binary-*=* | --[lm]a*=* | --reg*=*)
# These options require an argument and an argument has been provided
# with the --foo=argument syntax. All is good.
;;
(-[ABCDefmX] | --binary-* | --file | --[lm]a* | --reg*)
# These options require an argument which should now be in $1.
# If it isn't, display an error and exit.
case ${1?"$option option requires an argument"} in
(*\'*)
optarg=" '"$(printf '%sX\n' "$1" | LC_ALL=C sed "$escape");;
(*)
optarg=" '$1'";;
esac
shift;;
(--)
break;;
(-?*)
;;
(*)
case $option in
(*\'*)
operands="$operands '"$(printf '%sX\n' "$option" |
LC_ALL=C sed "$escape");;
(*)
operands="$operands '$option'";;
esac
${POSIXLY_CORRECT+break}
continue;;
esac
case $option in
(-[drRzZ] | --di* | --exc* | --inc* | --rec* | --nu*)
printf >&2 '%s: %s: Option not supported\n' "$0" "$option"
exit 2;;
(-[ef]* | --file | --file=* | --reg*)
have_pat=1;;
(--h | --he | --hel | --help)
printf '%s\n' "$usage" || exit 2
exit;;
(-H | --wi | --wit | --with | --with- | --with-f | --with-fi \
| --with-fil | --with-file | --with-filen | --with-filena | --with-filenam \
| --with-filename)
with_filename=1
continue;;
(-l | --files-with-*)
files_with_matches=1
continue;;
(-L | --files-witho*)
files_without_matches=1
continue;;
(-h | --no-f*)
no_filename=1;;
(-V | --v | --ve | --ver | --vers | --versi | --versio | --version)
printf '%s\n' "$version" || exit 2
exit;;
esac
case $option in
(*\'?*)
option=\'$(printf '%sX\n' "$option" | LC_ALL=C sed "$escape");;
(*)
option="'$option'";;
esac
grep="$grep $option$optarg"
done
eval "set -- $operands "'${1+"$@"}'
if test $have_pat -eq 0; then
case ${1?"Missing pattern; try '${0##*/} --help' for help"} in
(*\'*)
grep="$grep -e '"$(printf '%sX\n' "$1" | LC_ALL=C sed "$escape");;
(*)
grep="$grep -e '$1'";;
esac
shift
fi
if test $# -eq 0; then
set -- -
fi
exec 3>&1
# res=1 means that no file matched yet
res=1
for i; do
case $i in
*[-.][zZ] | *_z | *[-.]gz | *.t[ag]z) uncompress="gzip -cdf";;
*[-.]bz2 | *[-.]tbz | *.tbz2) uncompress="bzip2 -cdf";;
*[-.]lzo | *[-.]tzo) uncompress="lzop -cdf";;
*[-.]zst | *[-.]tzst) uncompress="zstd -cdfq";; # zstd needs -q.
*[-.]lz4) uncompress="lz4 -cdf";;
*) uncompress="$xz -cdfqQ";; # -qQ to ignore warnings like unsupp. check.
esac
# xz_status will hold the decompressor's exit status.
# Exit status of grep (and in rare cases, printf or sed) is
# available as the exit status of this assignment command.
xz_status=$(
exec 5>&1
($uncompress -- "$i" 5>&-; echo $? >&5) 3>&- |
if test $files_with_matches -eq 1; then
eval "$grep -q" && { printf '%s\n' "$i" || exit 2; }
elif test $files_without_matches -eq 1; then
eval "$grep -q" || {
r=$?
if test $r -eq 1; then
printf '%s\n' "$i" || r=2
fi
exit $r
}
elif test $with_filename -eq 0 &&
{ test $# -eq 1 || test $no_filename -eq 1; }; then
eval "$grep"
elif test $grep_supports_label -eq 1; then
# The grep implementation in use allows us to specify the filename
# that grep will prefix to the output lines. This is faster and
# less prone to security bugs than the fallback method that uses sed.
# This also avoids confusing output with GNU grep >= 3.5 (2020-09-27)
# which prints "binary file matches" to stderr instead of stdout.
#
# If reading from stdin, let grep use whatever name it prefers for
# stdin. With GNU grep it is a locale-specific translated string.
if test "x$i" = "x-"; then
eval "$grep -H"
else
eval "$grep -H --label \"\$i\""
fi
else
# Append a colon so that the last character will never be a newline
# which would otherwise get lost in shell command substitution.
i="$i:"
# Escape & \ | and newlines only if such characters are present
# (speed optimization).
case $i in
(*'
'* | *'&'* | *'\'* | *'|'*)
# If sed fails, set i to a known safe string to ensure that
# failing sed did not create a half-escaped dangerous string.
i=$(printf '%s\n' "$i" | LC_ALL=C sed 's/[&\|]/\\&/g; $!s/$/\\/') ||
i='(unknown filename):';;
esac
# $i already ends with a colon so do not add it here.
sed_script="s|^|$i|"
# If grep or sed fails, pick the larger value of the two exit statuses.
# If sed fails, use at least 2 since we use >= 2 to indicate errors.
r=$(
exec 4>&1
(eval "$grep" 4>&-; echo $? >&4) 3>&- |
LC_ALL=C sed "$sed_script" >&3 4>&-
) || {
sed_status=$?
test "$sed_status" -lt 2 && sed_status=2
test "$r" -lt "$sed_status" && r=$sed_status
}
exit $r
fi >&3 5>&-
)
r=$?
# If grep or sed or other non-decompression command failed with a signal,
# exit immediately and ignore the possible remaining files.
#
# NOTE: Instead of 128 + signal_number, some shells use
# 256 + signal_number (ksh) or 384 + signal_number (yash).
# This is fine for us since their "exit" and "kill -l" commands take
# this into account. (At least the versions I tried do but there is
# a report of an old ksh variant whose "exit" truncates the exit status
# to 8 bits without any special handling for values indicating a signal.)
test "$r" -ge 128 && exit "$r"
if test -z "$xz_status"; then
# Something unusual happened, for example, we got a signal and
# the exit status of the decompressor was never echoed and thus
# $xz_status is empty. Exit immediately and ignore the possible
# remaining files.
exit 2
elif test "$xz_status" -ge 128; then
# The decompressor died due to a signal. SIGPIPE is ignored since it can
# occur if grep exits before the whole file has been decompressed (grep -q
# can do that). If the decompressor died with some other signal, exit
# immediately and ignore the possible remaining files.
test "$(kill -l "$xz_status" 2> /dev/null)" != "PIPE" && exit "$xz_status"
elif test "$xz_status" -gt 0; then
# Decompression failed but we will continue with the remaining
# files anyway. Set exit status to at least 2 to indicate an error.
test "$r" -lt 2 && r=2
fi
# Since res=1 is the initial value, we only need to care about
# matches (r == 0) and errors (r >= 2) here; r == 1 can be ignored.
if test "$r" -ge 2; then
# An error occurred in decompressor, grep, or some other command. Update
# res unless a larger error code has been seen with an earlier file.
test "$res" -lt "$r" && res=$r
elif test "$r" -eq 0; then
# grep found a match and no errors occurred. Update res if no errors have
# occurred with earlier files.
test "$res" -eq 1 && res=0
fi
done
# 0: At least one file matched and no errors occurred.
# 1: No matches were found and no errors occurred.
# >=2: Error. It's unknown if matches were found.
exit "$res"