#!/bin/sh

# zgrep -- 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, 2009, 2010 Free Software
# Foundation

# Copyright (C) 1993 Jean-loup Gailly

# 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 3 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.

# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

bindir='/usr/bin'
case $1 in
--__bindir) bindir=${2?}; shift; shift;;
esac
PATH=$bindir:$PATH

grep='${GREP-grep}'

version='zgrep (gzip) 1.5
Copyright (C) 2010-2012 Free Software Foundation, Inc.
This is free software.  You may redistribute copies of it under the terms of
the GNU General Public License <http://www.gnu.org/licenses/gpl.html>.
There is NO WARRANTY, to the extent permitted by law.

Written by Jean-loup Gailly.'

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', except that the following 'grep'
options are not supported: --dereference-recursive (-R), --directories (-d),
--exclude, --exclude-from, --exclude-dir, --include, --null (-Z),
--null-data (-z), and --recursive (-r).

Report bugs to <bug-gzip@gnu.org>."

# sed script to escape all ' for the shell, and then (to handle trailing
# newlines correctly) append ' to the last line.
escape='
  s/'\''/'\''\\'\'''\''/g
  $s/$/'\''/
'
operands=
have_pat=0
files_with_matches=0
files_without_matches=0
no_filename=0
with_filename=0

while test $# -ne 0; do
  option=$1
  shift
  optarg=

  case $option in
  (-[0123456789EFGHIKLPRTUVZabchilnoqrsuvwxyz]?*)
    arg2=-\'$(expr "X$option" : 'X-.[0-9]*\(.*\)' | sed "$escape")
    eval "set -- $arg2 "'${1+"$@"}'
    option=$(expr "X$option" : 'X\(-.[0-9]*\)');;
  (--binary-*=* | --[lm]a*=* | --reg*=*)
    ;;
  (-[ABCDXdefm] | binary-* | --file | --[lm]a* | --reg*)
    case ${1?"$option option requires an argument"} in
    (*\'*)
      optarg=" '"$(printf '%s\n' "$1" | sed "$escape");;
    (*)
      optarg=" '$1'";;
    esac
    shift;;
  (-f?*\'*)
    optarg=" '"$(expr "X$option" : 'X-f\(.*\)' | sed "$escape")
    option=-f;;
  (-f?*)
    optarg=" '"$(expr "X$option" : 'X-f\(.*\)')\'
    option=-f;;
  (--file=*\'*)
    optarg=" '"$(expr "X$option" : 'X--file=\(.*\)' | sed "$escape")
    option=--file;;
  (--file=*)
    optarg=" '"$(expr "X$option" : 'X--file=\(.*\)')\'
    option=--file;;
  (--)
    break;;
  (-?*)
    ;;
  (*)
    case $option in
    (*\'*)
      operands="$operands '"$(printf '%s\n' "$option" | 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;;
  (-e* | --reg*)
    have_pat=1;;
  (-f | --file)
    # The pattern is coming from a file rather than the command-line.
    # If the file is actually stdin then we need to do a little
    # magic, since we use stdin to pass the gzip output to grep.
    # Turn the -f option into an -e option by copying the file's
    # contents into OPTARG.
    case $optarg in
    (" '-'" | " '/dev/stdin'" | " '/dev/fd/0'")
      option=-e
      optarg=" '"$(sed "$escape") || exit 2;;
    esac
    have_pat=1;;
  (--h | --he | --hel | --help)
    echo "$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;;
  (-L | --files-witho*)
    files_without_matches=1;;
  (-h | --no-f*)
    no_filename=1;;
  (-V | --v | --ve | --ver | --vers | --versi | --versio | --version)
    echo "$version" || exit 2
    exit;;
  esac

  case $option in
  (*\'?*)
    option=\'$(printf '%s\n' "$option" | sed "$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 -- '"$(printf '%s\n' "$1" | sed "$escape");;
  (*)
    grep="$grep -- '$1'";;
  esac
  shift
fi

if test $# -eq 0; then
  set -- -
fi

exec 3>&1
res=0

for i
do
  # Fail if gzip or grep (or sed) fails.
  gzip_status=$(
    exec 5>&1
    (gzip -cdfq -- "$i" 5>&-; echo $? >&5) 3>&- |
    if test $files_with_matches -eq 1; then
      eval "$grep" >/dev/null && { printf '%s\n' "$i" || exit 2; }
    elif test $files_without_matches -eq 1; then
      eval "$grep" >/dev/null || {
        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"
    else
      case $i in
      (*'
'* | *'&'* | *'\'* | *'|'*)
          icolon=$(printf '%s\n' "$i:" |
                     sed -e 's/[&\|]/\\&/g' -e '$!s/$/\\/');;
      (*) icolon="$i:";;
      esac
      sed_script="s|^|$icolon|"

      # Fail if grep or sed fails.
      r=$(
        exec 4>&1
        (eval "$grep" 4>&-; echo $? >&4) 3>&- | sed "$sed_script" >&3 4>&-
      ) && exit $r
      r=$?
      test 1 -lt $r && exit $r || exit 2
    fi >&3 5>&-
  )
  r=$?
  test 128 -lt $r && exit $r
  test "$gzip_status" -eq 0 || test "$gzip_status" -eq 2 || r=2
  test $res -lt $r && res=$r
done
exit $res
