#!/usr/local/bin/perl --	-*- Perl -*-

# Written by:
#    Matz Kindahl (matkin@docs.uu.se)

require 'getopts.pl';

sub Usage {
    "Usage : $pname [ -cdhilnsv ] [ -e exp ] [ -f file ] [ strings ] [ file ] ...\n";
}

($pname) = ($0 =~ m|/([^/]+)/?$|);
&Getopts("cdhilnpsvxe:f:");

if ($opt_f) {
    open(FD, $opt_f) || die "Cannot open $opt_f, stopped";
    chop(@regexp = <FD>);
    for (@regexp) { $_ = '(' . $_ . ')'; }
    $regexp = join('|',@regexp);
} else {
    $regexp = $opt_e ? $opt_e : shift;
}
die &Usage unless $regexp;

$regexp =~ s#/#\\/#g;
$regopt = $opt_i ? "i" : "";
$regexp = "^" . $regexp . "\$" if $opt_x;
$if_statement = $opt_v ? "unless" : "if";
$error_handling = $opt_s ? "" : 'print $@ if $@';
$initial_commands = '$found = 1;';
$match_commands = '$found = 0;';
if ($opt_c) {
    $initial_commands .= '$count = 0;';
    $match_commands .= '$count++;';
    $on_eof_commands = 'print ' . ($#ARGV < 1 ? "" : '"$ARGV:" . ') .
	'"$count\n"; $count = 0;';
} else {
    if ($opt_l) {
	$match_commands .= 'print "$ARGV\n"; next file;';
    } else {
	if (! $opt_h && $#ARGV > 0) {
	    $head = '$ARGV:';
	} 
	$head .= $opt_n ? '$.:' : "";
	$match_commands .= 'print "' . $head . '$_";';
    }
}

if ($opt_d) {
    $loop_command = 'while ($ARGV = shift)';
    $initial_commands .= q[unshift(\@ARGV, '-') if \$#ARGV < 0;];
} else {
    local($") = (', ');
    unshift(@ARGV, '-') if $#ARGV < 0;
    for (@ARGV) { $_ = "'$_'"; }
    $loop_command = "for \$ARGV (@ARGV)";
}

$program = <<"END";
$initial_commands
file: $loop_command {
    if (-d \$ARGV) {
	warn "$pname: \$ARGV: Is a directory!\\n";
	next file;
    }
    unless (open(ARGV, \$ARGV)) {
	warn "$pname: \$!\\n";
	next file;
    }
    line: while (<ARGV>) {
	do { $match_commands } $if_statement /$regexp/$regopt;
	$error_handling;
	if (eof(ARGV)) { $on_eof_commands close(ARGV); next file; }
    }
}
exit $found;
END

if ($opt_p) {
    print $program;
} else {
    eval $program;
}