#!/usr/bin/perl
##---------------------------------------------------------------------------##
##  File:
##	$Id: install.me,v 1.19 2003/07/20 00:00:51 ehood Exp $
##  Author:
##      Earl Hood, earl@earlhood.com
##  Summary:
##	Installation program for Perl applications.  It is an alternative
##	to the MakeMaker/Makefile.PL method for "pure" Perl applications.
##	This program provides an interactive method of installation.
##
##	Files to install are determined by the FILELIST file.  Each
##	file to install is listed in the file with a prefix telling
##	the installation program the type of file it is.
##---------------------------------------------------------------------------##
##    Copyright (C) 1997-2002	Earl Hood, earl@earlhood.com
##
##    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., 59 Temple Place - Suite 330, Boston, MA
##    02111-1307, USA
##---------------------------------------------------------------------------##

package InstallMe;

use strict;
use vars qw(  
    $MSDOS $MACOS $UNIX $VMS $WINDOWS
    $DIRSEP $DIRSEPRX $CURDIR
    $PROG $PATHSEP
    $OSType
    %DirSep %CurDir %PathSep
);
use Config;
use FileHandle;
use Getopt::Long;

my $MacCLPrompt = 0;
my $SkipPermCheck = 0;

###############################################################################
##	OS Configuration Code
###############################################################################

BEGIN {
    %DirSep = (
	macos	=> ':',
	msdos	=> '\\',
	unix	=> '/',
	vms	=> '/',	# ??
	windows	=> '\\',
    );
    %CurDir = (
	macos	=> ':',	# ??
	msdos	=> '.',
	unix	=> '.',
	vms	=> '.',	# ??
	windows	=> '.',
    );
    %PathSep = (
	macos	=> ';',	# ??
	msdos	=> ';',
	unix	=> ':',
	vms	=> ':',	# ??
	windows	=> ';',
    );

    my $dontknow = 0;

    ## Init variables
    $MACOS	= 0;	$MSDOS	= 0;
    $UNIX	= 0;	$VMS	= 0;
    $WINDOWS	= 0;
    $DIRSEP	= '/';	$CURDIR = '.';
    $PATHSEP	= ':';

    ## See if ostype can be determined from osname in Config
    if (defined $^O) {
	$_ = $^O;
    } else {
	require Config;
	$_ = $Config::Config{'osname'};
    }

    if (/mac/i) {
	$MACOS = 1;
	$OSType = 'macos';
    } elsif (/vms/i) {
	$VMS = 1;
	$OSType = 'vms';
    } elsif (/msdos/i || /\bdos\b/i) {
	$MSDOS = 1;
	$OSType = 'msdos';
    } elsif (/mswin/i or /winnt/i) {
	$WINDOWS = 1;  $MSDOS = 1;
	$OSType = 'windows';
    } elsif (/unix/i  || /aix/i     || /bsd/i   || /dynix/i  ||
	     /hpux/i  || /solaris/i || /sunos/i || /ultrix/i ||
	     /linux/i || /cygwin/i) {
	$UNIX = 1;
	$OSType = 'unix';
    } else {
	$dontknow = 1;
    }

    ## If we do not know now what the ostype is, make a guess.
    if ($dontknow) {
	my($tmp);

	## MSDOG/Windoze
	if (($tmp = $ENV{'windir'}) and ($tmp =~ /[A-Z]:\\/i) and (-d $tmp)) {
	    $MSDOS = 1;
	    $WINDOWS = 1;
	    $OSType = 'windows';

	} elsif (($tmp = $ENV{'COMSPEC'}) and ($tmp =~ /[a-zA-Z]:\\/) and
		 (-e $tmp)) {
	    $MSDOS = 1;
	    if ($tmp =~ /win/i) {
		$WINDOWS = 1;
		$OSType = 'windows';
	    } else {
		$OSType = 'msdos';
	    }

	## MacOS
	} elsif (defined($MacPerl::Version)) {
	    $MACOS = 1;
	    $OSType = 'macos';

	## Unix (fallback case)
	} else {
	    $UNIX = 1;
	    $OSType = 'unix';
	}
    }

    ## Set other variables
    $DIRSEP = $DirSep{$OSType};
    if ($MSDOS or $WINDOWS) {
	$DIRSEPRX = "\\\\\\/";
    } else {
	($DIRSEPRX = $DIRSEP) =~ s/(\W)/\\$1/g;
    }
    $CURDIR = $CurDir{$OSType};
    $PATHSEP = $PathSep{$OSType};

    ##	Store name of program
    ($PROG = $0) =~ s%.*[$DIRSEPRX]%%o;

    ##	Flag to prompt for command-line options on a Mac
    $MacCLPrompt = 1;
}

##---------------------------------------------------------------------------##
##	CLinit() initializes @ARGV.  Currently, it does nothing under
##	MSDOS and Unix.
##
##	If running under a Mac and the script is a droplet, command-line
##	options will be prompted for if $MacCLPrompt is set to a
##	non-zero value.
##
sub CLinit {

    ##	Ask for command-line options if script is a Mac droplet
    ##		Code taken from the MacPerl FAQ
    ##
    if ($MacCLPrompt && defined($MacPerl::Version) &&
	    ($MacPerl::Version =~ /Application$/)) {

	# we're running from the app
	my( $cmdLine, @args );
	$cmdLine = &MacPerl::Ask( "Enter command line options:" );
	require "shellwords.pl";
	@args = &shellwords( $cmdLine );
	unshift( @::ARGV, @args );
    }
}

##---------------------------------------------------------------------------##
##	path_join takes an array of path components and returns a string
##	with components joined together by the directoy separator.
##
sub path_join {
    join($DIRSEP, @_);
}

##---------------------------------------------------------------------------##
##	path_split takes a string representing a pathname and splits
##	it into an array of components.  The pathname is interpreted
##	with respect to the OS we are running under.
##
sub path_split {
    split(/[$DIRSEPRX]/o, $_[0]);
}

##---------------------------------------------------------------------------##
##	is_absolute_path() returns true if a string is an absolute path
##
sub is_absolute_path {

    if ($MSDOS or $WINDOWS) {
	return $_[0] =~ /^(?:[a-z]:)?[\\\/]/i;
    }
    if ($MACOS) {		## Not sure about Mac
	return $_[0] =~ /^:/o;
    }
    if ($VMS) {			## Not sure about VMS
	return $_[0] =~ /^\w+:/i;
    }
    $_[0] =~ m|^/|o;    	## Unix
}

###############################################################################
##	Initialize Globals
###############################################################################

my %Files	= ();
my %DefValues	= ();
my %OptValues	= ();

my $Root	= '';

###############################################################################
##	Parse Command-line
###############################################################################

{
    CLinit();
    my $ret =
    GetOptions(\%OptValues,
	       qw(
		   afs
		   root=s
		   batch
		   binpath=s
		   docpath=s
		   filelist=s
		   libpath=s
		   manpath=s
		   nobin
		   nodep
		   nodoc
		   nolib
		   noman
		   perl=s
		   prefix=s

		   help));

    if (!$ret or $OptValues{"help"}) {
	usage();
	exit !$ret;
    }

    $Root		  = $OptValues{'root'}  if defined $OptValues{'root'};

    my $cfg_prefix        = interpolate_path($Config{'prefix'});
    $DefValues{'binpath'} = interpolate_path($Config{'installbin'});
    $DefValues{'libpath'} = interpolate_path($Config{'installsitelib'});
    $DefValues{'manpath'} = interpolate_path($Config{'installman1dir'});
    if (defined($OptValues{'prefix'})) {
	$DefValues{'binpath'} = join($DIRSEP, $OptValues{'prefix'}, 'bin')
	    unless $DefValues{'binpath'} =~
		   s/^\Q$cfg_prefix/$OptValues{'prefix'}/o;
	$DefValues{'libpath'} = join($DIRSEP, $OptValues{'prefix'}, 'lib')
	    unless $DefValues{'libpath'} =~
		   s/^\Q$cfg_prefix/$OptValues{'prefix'}/o;
	$DefValues{'manpath'} = join($DIRSEP, $OptValues{'prefix'}, 'man')
	    unless $DefValues{'manpath'} =~
		   s/^\Q$cfg_prefix/$OptValues{'prefix'}/o;
	$DefValues{'docpath'} = join($DIRSEP, $OptValues{'prefix'}, 'doc');

    } else {
	$DefValues{'docpath'} = join($DIRSEP, $cfg_prefix, 'doc');
    }
    $DefValues{'manpath'} =~ s|(${DIRSEPRX}man)${DIRSEPRX}.*|$1|;

    $DefValues{'filelist'} = 'FILELIST';
    $DefValues{'perl'}     = $Config{'perlpath'};

    $SkipPermCheck = 1  if $OptValues{'afs'};

    ## If VMS, tweak pathnames
    if ($VMS) {
      my($key);
      foreach $key (keys(%DefValues)) {
        $DefValues{$key} =~ s|:||;
        $DefValues{$key} =~ s|[\.\[\]]|/|g;
        $DefValues{$key} =~ s|000000||g;
        $DefValues{$key} =~ s|//|/|g;
      }
    }
}

###############################################################################
##	Do It
###############################################################################

{
    my($dodep, $dobin, $dolib, $dodoc, $doman);

    ## Get installation files
    ## ----------------------
    read_manifest($OptValues{'filelist'} || $DefValues{'filelist'},
		  \%Files);

    $DefValues{'docpath'} .= $DIRSEP . $Files{'name'}[0]
	if $Files{'name'}[0];
    $dodep = defined($Files{'dep'}) && scalar(@{$Files{'dep'}}) &&
	     !$OptValues{'nodep'};
    $dobin = defined($Files{'bin'}) && scalar(@{$Files{'bin'}}) &&
	     !$OptValues{'nobin'};
    $dolib = defined($Files{'lib'}) && scalar(@{$Files{'lib'}}) &&
	     !$OptValues{'nolib'};
    $dodoc = defined($Files{'doc'}) && scalar(@{$Files{'doc'}}) &&
	     !$OptValues{'nodoc'};
    $doman = defined($Files{'man'}) && scalar(@{$Files{'man'}}) &&
	     !$OptValues{'noman'};
    die "Nothing to install!\n"
	unless $dobin or $dolib or $dodoc or $doman;

    ## Check for dependencies
    ## ----------------------
    if ($dodep) {
	print STDOUT "Checking dependencies:\n";
	my($mod);
	my(@dont_exist) = ();
	foreach $mod (@{$Files{'dep'}}) {
	    print STDOUT sprintf("\t%s %s ", $mod, ('.'x(30-length($mod))));
	    if ($mod =~ /\.pl$/) {
		eval {
		    require $mod;
		};
	    } else {
		eval qq{
		    require $mod;
		};
	    }
	    if ($@) {
		print STDOUT "NOT OK!\n";
		push(@dont_exist, $mod);
	    } else {
		print STDOUT "ok\n";
	    }
	}
	if (@dont_exist) {
	    die "ERROR: Dependency check FAILED\n";
	}
    }

    ## Get path stuff
    ## --------------
    if ($OptValues{'batch'}) {
	$OptValues{'perl'} = $DefValues{'perl'}
	    unless $OptValues{'perl'};
	$OptValues{'binpath'}  = $DefValues{'binpath'}
	    unless $OptValues{'binpath'};
	$OptValues{'libpath'}  = $DefValues{'libpath'}
	    unless $OptValues{'libpath'};
	$OptValues{'docpath'}  = $DefValues{'docpath'}
	    unless $OptValues{'docpath'};
	$OptValues{'manpath'}  = $DefValues{'manpath'}
	    unless $OptValues{'manpath'};
    } else {
	while (1) {
	    $OptValues{'perl'} =
		get_perl_from_user($OptValues{'perl'},
				   $DefValues{'perl'},
				   "Pathname of perl executable:");
	    $OptValues{'binpath'} =
		get_path_from_user($OptValues{'binpath'},
				   $DefValues{'binpath'},
				   "Directory to install executables:")
				   if $dobin;
	    $OptValues{'libpath'} =
		get_path_from_user($OptValues{'libpath'},
				   $DefValues{'libpath'},
				   "Directory to install library files:")
				   if $dolib;
	    $OptValues{'docpath'} =
		get_path_from_user($OptValues{'docpath'},
				   $DefValues{'docpath'},
				   "Directory to install documentation:")
				   if $dodoc;
	    $OptValues{'manpath'} =
		get_path_from_user($OptValues{'manpath'},
				   $DefValues{'manpath'},
				   "Directory to install manpages:")
				   if $doman;

	    print STDOUT "You have specified the following:\n";
	    print STDOUT "\tPerl path: $OptValues{'perl'}\n";
	    print STDOUT "\tBin directory: $OptValues{'binpath'}\n"
		if $dobin;
	    print STDOUT "\tLib directory: $OptValues{'libpath'}\n"
		if $dolib;
	    print STDOUT "\tDoc directory: $OptValues{'docpath'}\n"
		if $dodoc;
	    print STDOUT "\tMan directory: $OptValues{'manpath'}\n"
		if $doman;

	    last  if prompt_user_yn("Is this correct?", 1);

	    $DefValues{'perl'} = $OptValues{'perl'};
	    $DefValues{'binpath'}  = $OptValues{'binpath'};
	    $DefValues{'libpath'}  = $OptValues{'libpath'};
	    $DefValues{'docpath'}  = $OptValues{'docpath'};
	    $DefValues{'manpath'}  = $OptValues{'manpath'};
	    $OptValues{'perl'} = '';
	    $OptValues{'binpath'}  = '';
	    $OptValues{'libpath'}  = '';
	    $OptValues{'docpath'}  = '';
	    $OptValues{'manpath'}  = '';
	}
    }

    ## Install files
    ## -------------
    my $plprefix  = "#!$OptValues{'perl'}\n";
       $plprefix .= "use lib qw($OptValues{'libpath'});\n"
		    if $OptValues{'libpath'};
    my($file, $destfile);
    if ($dobin) {
	print STDOUT qq(Installing programs to "$OptValues{'binpath'}":\n);
	if (create_dir(apply_root($Root, $OptValues{'binpath'}), 1) <= 0) {
	    die "\n";
	}
	foreach (@{$Files{'bin'}}) {
	    print STDOUT "    $_ => ";
	    ($file = $_) =~ s%.*/%%o;
	    $destfile = join('', $OptValues{'binpath'}, $DIRSEP, $file);
	    my $fulldestfile = apply_root($Root, $destfile);
	    print STDOUT $destfile, "\n";
	    cp($_, $fulldestfile, $plprefix, $WINDOWS);
	    eval q{chmod 0755, $fulldestfile;};
	    if ($WINDOWS && $file !~ /\.pl$/i) {
		$fulldestfile .= ".pl";
		cp($_, $fulldestfile, $plprefix);
		eval q{chmod 0755, $fulldestfile;};
	    }
	}
    }
    if ($dolib) {
	print STDOUT qq(Installing lib files to "$OptValues{'libpath'}":\n);
	if (create_dir(apply_root($Root, $OptValues{'libpath'}), 1) <= 0) {
	    die "\n";
	}
	foreach (@{$Files{'lib'}}) {
	    print STDOUT "    $_ => ";
	    ($file = $_) =~ s%.*/%%o;
	    $destfile = join('', $OptValues{'libpath'}, $DIRSEP, $file);
	    print STDOUT $destfile, "\n";
	    cp($_, apply_root($Root, $destfile));
	}
    }
    if ($dodoc) {
	print STDOUT qq(Installing docs to "$OptValues{'docpath'}":\n);
	if (create_dir(apply_root($Root, $OptValues{'docpath'}), 1) <= 0) {
	    die "\n";
	}
	foreach (@{$Files{'doc'}}) {
	    print STDOUT "    $_ => ";
	    ($file = $_) =~ s%.*/%%o;
	    $destfile = join('', $OptValues{'docpath'}, $DIRSEP, $file);
	    print STDOUT $destfile, "\n";
	    cp($_, apply_root($Root, $destfile));
	}
    }
    if ($doman) {
	my($sect, $msubdir);
	print STDOUT qq(Installing manpages to "$OptValues{'manpath'}":\n);
	if (create_dir(apply_root($Root, $OptValues{'manpath'}), 1) <= 0) {
	    die "\n";
	}
	foreach (@{$Files{'man'}}) {
	    print STDOUT "    $_ => ";
	    ($file = $_)    =~ s%.*/%%o;
	    ($sect = $file) =~ s%.*\.%%o;
	    $msubdir  = join($DIRSEP, $OptValues{'manpath'}, "man$sect");
	    if (create_dir(apply_root($Root, $msubdir), 1) <= 0) { die "\n"; }
	    $destfile = join($DIRSEP, $msubdir, $file);
	    print STDOUT $destfile, "\n";
	    cp($_, apply_root($Root, $destfile));
	}
    }
}

###############################################################################
##	Subroutines
###############################################################################

##------------------------------------------------------------------------
##	read_manifest() reads file giving list of all files to
##	install.
##
sub read_manifest {
    my $file	= shift;
    my $href	= shift;
    my($key, $pathname);

    open FILE, $file or die qq(Unable to open "$file"\n);
    while (<FILE>) {
	next  if /^#/;
	next  unless /\S/;
	chomp;
	($key, $pathname) = split(/:/, $_, 2);
	push @{$href->{$key}}, $pathname;
    }
    close FILE;
}

##------------------------------------------------------------------------
##	perl_exe() returns true if pathname argument is a perl
##	interpreter.
##
sub perl_exe {
    my $pathname = shift;

    return 0  unless -x $pathname;
    return 0  unless open PERL, "$pathname -v |";
    while (<PERL>) {
	if (/\bperl\b/i) {
	    close PERL;
	    return 1;
	}
    }
    close PERL;
    0;
}

##------------------------------------------------------------------------
##	get_perl_from_user() gets the pathname of the perl executable.
##
sub get_perl_from_user {
    my $value	= shift;	# Current value (if set, batch mode)
    my $default	= shift;	# Default value
    my $prompt	= shift;	# User prompt

    if (defined($value) && ($value =~ /\S/)) {
	die qq(ERROR: "$value" is not perl.\n)
	    unless perl_exe($value);
    } else {
	while (1) {
	    $value = interpolate_path(prompt_user($prompt, $default));
	    last  if perl_exe($value);
	    warn qq(ERROR: "$value" is not perl.\n);
	}
    }
    $value;
}

##------------------------------------------------------------------------
##	apply_root() applies install base root path to given path.
##
sub apply_root {
  my $base = shift;
  my $path = shift;
  if ($base) {
    return $base . $path;
  }
  $path;
}

##------------------------------------------------------------------------
##	get_path_from_user() gets a path from the user.  The function
##	insures the path exists.
##
sub get_path_from_user {
    my $value	= shift;	# Current value (if set, batch mode)
    my $default	= shift;	# Default value
    my $prompt	= shift;	# User prompt

    if (defined($value) && ($value =~ /\S/)) {
	die qq(ERROR: Unable to create "$value".\n)
	    unless create_dir(apply_root($Root, $value), 1) > 0;
    } else {
	my $stat;
	while (1) {
	    $value = interpolate_path(prompt_user($prompt, $default));
	    $stat = create_dir(apply_root($Root, $value));
	    if ($stat > 0)  { last; }
	    if ($stat == 0) { next; }
	}
    }
    $value;
}

##------------------------------------------------------------------------
##	create_dir() creates a directory path
##
sub create_dir {
    my $d	= shift;	# Directory path
    my $noask	= shift;	# Don't ask to create flag

    if (-e $d) {
	if ($SkipPermCheck || -w $d) { return 1; }
	warn qq/"$d" is not writable\n/;
	return -1;
    }

    my(@a) = grep($_ ne '', split(/[$DIRSEPRX]/o, $d));
    my($path, $dir, $curpath);

    if (!$noask) {
        return 0  unless prompt_user_yn(qq{"$d" does not exist.  Create}, 1);
    }
    if ($MSDOS) {
	if ($d =~ m%^\s*(?:[a-zA-Z]:)?[/\\]%) {
	    $path = shift @a;
	} else {
	    $path = $CURDIR;
	}
    } else {
	if ($d =~ /^\s*\//) {
	    $path = '';
	} else {
	    $path = $CURDIR;
	}
    }
    foreach $dir (@a) {
	$curpath = "$path$DIRSEP$dir";
	if (! -e $curpath) {
	    if (!mkdir($curpath, 0777)) {
		warn qq/Unable to create "$curpath": $!\n/;
		return -1;
	    }
	} elsif (! -d $curpath) {
	    warn qq/"$curpath" is not a directory\n/;
	    return -1;
	}
	$path .= $DIRSEP . $dir;
    }
    if (!$SkipPermCheck && (! -w $d)) {
	warn qq/"$d" not writable\n/;
	return -1;
    }
    1;
}

##------------------------------------------------------------------------
##	interpolate_path() expands any special characters in a pathname.
##
sub interpolate_path {
    my($path) = shift;

    $path =~ s/^~($DIRSEPRX|$)/$ENV{'HOME'}$1/o;
    $path =~ s/^(~\w+)($DIRSEPRX|$)/get_user_home_dir($1).$2/oe;
    $path =~ s/\$(\w+)/defined($ENV{$1})?$ENV{$1}:"\$$1"/ge;
    $path =~ s/\$\{(\w+)\}/defined($ENV{$1})?$ENV{$1}:"\${$1}"/ge;
    $path;
}

##------------------------------------------------------------------------
##	get_user_home_dir() retrieves home directory for a given user.
##
sub get_user_home_dir {
    my $orguser = shift;
    my $user = $orguser;
       $user =~ s/~//g;
    my @pwent = getpwnam($user);
    return scalar(@pwent) ? $pwent[7] : $orguser;
}

##------------------------------------------------------------------------
##	cp() copies a file, or directory.
##
sub cp {
    my($src, $dst, $prepend, $mkbat) = @_;

    if (-d $src) {
	if (! -e $dst) {
	    mkdir($dst,0777) or die "Unable to create $dst: $!\n";
	}
	opendir(DIR, $src) or die "Unable to open $src: $!\n";
	my @files = grep(!/^(sccs|\.|\..)$/i, readdir(DIR));
	closedir(DIR);
	my($file, $srcpn, $dstpn);
	foreach $file (@files) {
	    $srcpn = "$src$DIRSEP$file";
	    $dstpn = "$dst$DIRSEP$file";
	    if (-d $srcpn) {
		cp($srcpn, $dstpn, $prepend, $mkbat);
	    } else {
		cpfile($srcpn, $dstpn, $prepend, $mkbat);
	    }
	}


    } else {
	cpfile($src, $dst, $prepend, $mkbat);
    }
}

##------------------------------------------------------------------------
##	cpfile() copies a file.  Any text in $prepend will be prepending
##	to the destination file.
##
sub cpfile {
    my($src, $dst, $prepend, $mkbat) = @_;
    my($bflag);

    if (-d $dst) {
	my $tmp;
	($tmp = $src) =~ s%.*[$DIRSEPRX]%%o;
	$dst .= $DIRSEP . $tmp;
    }

    open(SRC, $src) or die "Unable to open $src: $!\n";

    $bflag = (-B $src);
    $mkbat = 0       if ($dst =~ /\.bat$/i);
    $dst  .= '.bat'  if (!$bflag && $mkbat);

    open(DST, "> $dst") or die "Unable to create $dst: $!\n";
    if ($bflag) { binmode(SRC); binmode(DST); }

    if (!$bflag && $mkbat) {
	print DST <<'EndOfBat';
@rem = '--*-Perl-*--
@echo off
if "%OS%" == "Windows_NT" goto WinNT
perl -x -S "%0" %1 %2 %3 %4 %5 %6 %7 %8 %9
goto endofperl
:WinNT
perl -x -S "%0" %*
if NOT "%COMSPEC%" == "%SystemRoot%\system32\cmd.exe" goto endofperl
if %errorlevel% == 9009 echo You do not have perl in your PATH.
goto endofperl
@rem ';
EndOfBat
    }
    if ($prepend) {
	print DST $prepend;
    }
    print DST <SRC>;

    if (!$bflag && $mkbat) {
	print DST <<'EndOfBat';
__END__
:endofperl
EndOfBat
    }

    close(SRC);
    close(DST);
}

##------------------------------------------------------------------------
##      prompt_user() prompts the user for some input.  The first
##      argument is the prompt string, the second is the default
##      value is the user specifies nothing.
##
sub prompt_user {
    my $prompt = shift;
    my $default = shift;
 
    my($answer);
 
    print STDOUT $prompt;
    print STDOUT qq{ ("$default")}  if defined($default);
    print STDOUT " ";
    $answer = <STDIN>;
    chomp $answer;
    $answer = $default  if $answer !~ /\S/;
    $answer;
}
 
##------------------------------------------------------------------------
##      prompt_user_yn() prompts the user for a yes or no question.
##
sub prompt_user_yn {
    my $prompt = shift;
    my $default = shift;
 
    my($answer);
 
    print STDOUT $prompt, " ";
    print STDOUT $default ? "['y']" : "['n']"; 
    print STDOUT " ";
    $answer = <STDIN>;
    chomp $answer;
    if ($answer !~ /\S/) {
        $answer = $default;
    } elsif ($answer =~ /q/i or $answer =~ /quit/i) {
	print STDOUT "Installation aborted!\n";
	exit(0);
    } elsif ($answer =~ /y/i or $answer =~ /yes/i) {
        $answer = 1;
    } else {
        $answer = 0;
    }
    $answer;
}

##---------------------------------------------------------------------------##
##
sub usage {
    print STDOUT <<EOF;
Usage: $PROG [options]
Options:
  -afs                  : Skip permission checks (useful if AFS)
  -batch                : Run in batch mode (do not ask questions)
  -binpath <path>       : Directory path to install programs/scripts
  -docpath <path>       : Directory path to install documentation
  -help                 : This message
  -libpath <path>       : Directory path to install library files
  -filelist <file>      : List of files to install (def="FILELIST")
  -manpath <path>       : Directory path to manpages
  -nobin                : Do not install programs
  -nodep                : Skip module dependency check
  -nodoc                : Do not install documentation
  -nolib                : Do not install library files
  -noman                : Do not install manpages
  -perl <pathname>      : Pathname of perl interpreter
  -prefix <path>        : Set prefix for installation directories
EOF
}

