#!/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 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 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.

# 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.

PATH="BINDIR:$PATH"; export PATH

prog=`echo "$0" | sed 's|.*/||'`
case "$prog" in
	*egrep)	grep=${EGREP-egrep}	;;
	*fgrep)	grep=${FGREP-fgrep}	;;
	*)	grep=${GREP-grep}	;;
esac

version="z$grep (gzip) @VERSION@
Copyright (C) 2006 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: z$grep [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 <bug-gzip@gnu.org>."

pat=""
after_dash_dash=""
files_with_matches=0
files_without_matches=0
no_filename=0
with_filename=0

while test $# -ne 0; do
  case "$after_dash_dash$1" in
  --d* | --rec*)	echo >&2 "$0: $1: option not supported"; exit 2;;
  --h*)			echo "$usage" || exit 2; exit;;
  --files-with-*)	files_with_matches=1;;
  --files-witho*)	files_without_matches=1;;
  --no-f*)	no_filename=1;;
  --v*)		echo "$version" || exit 2; exit;;
  --wi*)	with_filename=1;;
  --*)	;;
  -*)
	case "$1" in
	-*[dr]*) echo >&2 "$0: $1: option not supported"; exit 2;;
	esac
	case "$1" in
	-*H*)	with_filename=1;;
	esac
	case "$1" in
	-*h*)	no_filename=1;;
	esac
	case "$1" in
	-*L*)	files_without_matches=1;;
	esac
	case "$1" in
	-*l*)	files_with_matches=1;;
	esac;;
  esac
  case "$after_dash_dash$1" in
  -[ef])   opt="$opt $1"; shift; pat="$1"
           if test "$grep" = grep; then  # grep is buggy with -e on SVR4
             grep=egrep
           fi;;
  -[ABCdm])opt="$opt $1 $2"; shift;;
  --)      opt="$opt $1"; after_dash_dash=1;;
  -*)	   opt="$opt $1";;
   *)      if test -z "$pat"; then
	     pat="$1"
	   else
	     break;
           fi;;
  esac
  shift
done

if test -z "$pat"; then
  echo "$usage"
  exit 2
fi

if test $# -eq 0; then
  gzip -cdfq | $grep $opt "$pat"
  exit $?
fi

res=0
for i do
  gzip -cdfq -- "$i" |
    if test $files_with_matches -eq 1; then
      $grep $opt "$pat" > /dev/null && printf '%s\n' "$i"
    elif test $files_without_matches -eq 1; then
      $grep $opt "$pat" > /dev/null || printf '%s\n' "$i"
    elif test $with_filename -eq 0 && { test $# -eq 1 || test $no_filename -eq 1; }; then
      $grep $opt "$pat"
    else
      escaped=
      while :; do
	case $i in
	*'
'*)
	  char='
'	  repl='\\n';;
	*'&'*) char='&' repl='\&';;
	*'\'*) char='\\' repl='\\';;
	*'|'*) char='|' repl='\|';;
	*) break;;
	esac
	up_to_first_char="\\([^$char]*\\)"
	after_first_char="[^$char]*$char\\(.*\\)"
	escaped=$escaped`expr "X$i" : "X$up_to_first_char"`$repl
 	i=`expr "X$i" : "$after_first_char"`
      done
      if test $with_filename -eq 1; then
	sed_script="s|[^:]*|$escaped$i|"
      else
	sed_script="s|^|$escaped$i:|"
      fi

      # Fail if either grep or sed fails.
      # Bash has ${PIPESTATUS[0]}, but that's not portable.
      exec 3>&1
      r=`
	exec 4>&1
	($grep $opt "$pat" 4>&-; echo $? >&4) 3>&- | sed "$sed_script" >&3 4>&-
      ` &&
      exit $r
    fi
  r=$?
  test $res -lt $r && res=$r
done
exit $res