package fs::mount_options; # $Id$

use diagnostics;
use strict;

use common;
use fs::type;
use log;

sub list() {
    my %non_defaults = (
			sync => 'async', noatime => 'atime', noauto => 'auto', ro => 'rw', 
			user => 'nouser', nodev => 'dev', noexec => 'exec', nosuid => 'suid',
		       );
    my @user_implies = qw(noexec nodev nosuid);
    \%non_defaults, \@user_implies;
}

sub unpack {
    my ($part) = @_;
    my $packed_options = $part->{options};

    my ($non_defaults, $user_implies) = list();

    my @auto_fs = fs::auto_fs();
    my %per_fs = (
		  iso9660 => [ qw(unhide) ],
		  vfat => [ qw(umask=0 umask=0022) ],
		  ntfs => [ qw(umask=0 umask=0022) ],
		  nfs => [ qw(rsize=8192 wsize=8192) ],
		  smbfs => [ qw(username= password=) ],
		  davfs => [ qw(username= password= uid= gid=) ],
		  reiserfs => [ 'notail' ],
		 );
    push @{$per_fs{$_}}, 'usrquota', 'grpquota' foreach 'ext2', 'ext3', 'xfs';

    while (my ($fs, $l) = each %per_fs) {
	$part->{fs_type} eq $fs || $part->{fs_type} eq 'auto' && member($fs, @auto_fs) or next;
	$non_defaults->{$_} = 1 foreach @$l;
    }

    $non_defaults->{encrypted} = 1 if !$part->{isFormatted} || isSwap($part);

    $non_defaults->{supermount} = 1 if $part->{fs_type} =~ /:/ || member($part->{fs_type}, 'auto', @auto_fs);

    my $defaults = { reverse %$non_defaults };
    my %options = map { $_ => '' } keys %$non_defaults;
    my @unknown;
    foreach (split(",", $packed_options)) {
	if ($_ eq 'user') {
	    $options{$_} = 1 foreach 'user', @$user_implies;
	} elsif (exists $non_defaults->{$_}) {
	    $options{$_} = 1;
	} elsif ($defaults->{$_}) {
	    $options{$defaults->{$_}} = 0;
	} elsif (/(.*?=)(.*)/) {
	    $options{$1} = $2;
	} else {
	    push @unknown, $_;
	}
    }
    # merge those, for cleaner help
    $options{'rsize=8192,wsize=8192'} = delete $options{'rsize=8192'} && delete $options{'wsize=8192'}
      if exists $options{'rsize=8192'};

    my $unknown = join(",", @unknown);
    \%options, $unknown;
}

sub pack_ {
    my ($_part, $options, $unknown) = @_;

    my ($non_defaults, $user_implies) = list();
    my @l;

    my @umasks = map {
	if (/^umask=/) {
	    my $v = delete $options->{$_};
	    /^umask=(.+)/ ? if_($v, $1) : $v;
	} else { () }
    } keys %$options;
    if (@umasks) {
	push @l, 'umask=' . min(@umasks);
    }

    if (delete $options->{user}) {
	push @l, 'user';
	foreach (@$user_implies) {
	    if (!delete $options->{$_}) {
		# overriding
		$options->{$non_defaults->{$_}} = 1;
	    }
	}
    }
    push @l, map_each { if_($::b, $::a =~ /=$/ ? "$::a$::b" : $::a) } %$options;
    push @l, $unknown;

    join(",", uniq(grep { $_ } @l));
}
sub pack {
    my ($part, $options, $unknown) = @_;
    $part->{options} = pack_($part, $options, $unknown);
    noreturn();
}

# update me on each util-linux new release:
sub help() {
    (

	'grpquota' => '',

	'noatime' => N("Do not update inode access times on this file system
(e.g, for faster access on the news spool to speed up news servers)."),

	'noauto' => N("Can only be mounted explicitly (i.e.,
the -a option will not cause the file system to be mounted)."),

	'nodev' => N("Do not interpret character or block special devices on the file system."),

	'noexec' => N("Do not allow execution of any binaries on the mounted
file system. This option might be useful for a server that has file systems
containing binaries for architectures other than its own."),

	'nosuid' => N("Do not allow set-user-identifier or set-group-identifier
bits to take effect. (This seems safe, but is in fact rather unsafe if you
have suidperl(1) installed.)"),

	'ro' => N("Mount the file system read-only."),

	'sync' => N("All I/O to the file system should be done synchronously."),

	'supermount' => '',

	'user' => N("Allow an ordinary user to mount the file system. The
name of the mounting user is written to mtab so that he can unmount the file
system again. This option implies the options noexec, nosuid, and nodev
(unless overridden by subsequent options, as in the option line
user,exec,dev,suid )."),

	'usrquota' => '',

        'umask=0' => N("Give write access to ordinary users"),

        'umask=0022' => N("Give read-only access to ordinary users"),
    );
}


sub rationalize {
    my ($part) = @_;

    my ($options, $unknown) = &unpack($part);

    if ($part->{fs_type} ne 'reiserfs') {
	$options->{notail} = 0;
    }

    &pack($part, $options, $unknown);
}

sub set_default {
    my ($part, %opts) = @_;
    #- opts are: useSupermount security iocharset codepage ignore_is_removable

    my ($options, $unknown) = &unpack($part);

    if (!$opts{ignore_is_removable} && $part->{is_removable} && !member($part->{mntpoint}, qw(/ /usr /var /boot))) {
	$options->{supermount} = $opts{useSupermount} && !($opts{useSupermount} eq 'magicdev' && $part->{media_type} eq 'cdrom');
	$part->{fs_type} = !$options->{supermount} ? 'auto' :
		    $part->{media_type} eq 'cdrom' ? 'udf:iso9660' : 'ext2:vfat';
	$options->{sync} = 1 if $part->{media_type} ne 'cdrom';
    }

    if ($part->{media_type} eq 'cdrom') {
	$options->{ro} = 1;
    }

    if ($part->{media_type} eq 'fd') {
	# slow device so don't loose time, write now!
	$options->{sync} = 1;
    }

    if (isTrueFS($part)) {
	#- noatime on laptops (do not wake up the hd)
	#- Do  not  update  inode  access times on this
	#- file system (e.g, for faster access  on  the
	#- news spool to speed up news servers).
	$options->{noatime} = detect_devices::isLaptop();
    }
    if ($part->{fs_type} eq 'nfs') {
	put_in_hash($options, { 
			       nosuid => 1, 'rsize=8192,wsize=8192' => 1, soft => 1,
			      });
    }
    if ($part->{fs_type} eq 'smbfs') {
	add2hash($options, { 'username=' => '%' }) if !$options->{'credentials='};
    }
    if (fs::type::can_be_this_fs_type($part, 'vfat')) {

	put_in_hash($options, {
			       users => 1, noexec => 0,
			      }) if $part->{is_removable};

	put_in_hash($options, {
			       'umask=0' => $opts{security} < 3, 'umask=0022' => $opts{security} < 4,
			       'iocharset=' => $opts{iocharset}, 'codepage=' => $opts{codepage},
			      });
    }
    if ($part->{fs_type} eq 'ntfs') {
	put_in_hash($options, { ro => 1, 'nls=' => $opts{iocharset},
				'umask=0' => $opts{security} < 3, 'umask=0022' => $opts{security} < 4,
			      });
    }
    if (fs::type::can_be_this_fs_type($part, 'iso9660')) {
	put_in_hash($options, { user => 1, noexec => 0, 'iocharset=' => $opts{iocharset} });
    }
    if ($part->{fs_type} eq 'reiserfs') {
	$options->{notail} = 1;
    }
    if (isLoopback($part) && !isSwap($part)) { #- no need for loop option for swap files
	$options->{loop} = 1;
    }

    # rationalize: no need for user
    if ($options->{autofs} || $options->{supermount}) {
	$options->{users} = $options->{user} = 0;
    }

    if ($options->{user} || $options->{users}) {
        # have noauto when we have user
        $options->{noauto} = 1;
	# ensure security  (user_implies - noexec as noexec is not a security matter)
	$options->{$_} = 1 foreach 'nodev', 'nosuid';
    }

    &pack($part, $options, $unknown);

    rationalize($part);
}

sub set_all_default {
    my ($all_hds, %opts) = @_;
    #- opts are: useSupermount security iocharset codepage

    foreach my $part (fs::get::really_all_fstab($all_hds)) {
	set_default($part, %opts);
    }
}

1;