package loopback; # $Id$

use diagnostics;
use strict;

#-######################################################################################
#- misc imports
#-######################################################################################
use MDK::Common::System;
use common;
use partition_table qw(:types);
use fs;
use fsedit;
use log;


sub carryRootLoopback {
    my ($part) = @_;
    $_->{mntpoint} eq '/' and return 1 foreach @{$part->{loopback} || []};
    0;
}

sub check_circular_mounts {
    my ($_hd, $part, $all_hds) = @_;

    my $fstab = [ fsedit::get_all_fstab($all_hds), $part ]; # no pb if $part is already in $all_hds

    my $base_mntpoint = $part->{mntpoint};
    my $check; $check = sub {
	my ($part, @seen) = @_;
	push @seen, $part->{mntpoint} || return;
	@seen > 1 && $part->{mntpoint} eq $base_mntpoint and die N("Circular mounts %s\n", join(", ", @seen));
	if (my $part = fs::up_mount_point($part->{mntpoint}, $fstab)) {
	    #- '/' carrier is a special case, it will be mounted first
	    $check->($part, @seen) if !carryRootLoopback($part);
	}
	if (isLoopback($part)) {
	    $check->($part->{loopback_device}, @seen);
	}
    };
    $check->($part) if !($base_mntpoint eq '/' && isLoopback($part)); #- '/' is a special case, no loop check
}

sub carryRootCreateSymlink {
    my ($part, $prefix) = @_;

    carryRootLoopback($part) or return;

    my $mntpoint = "$prefix$part->{mntpoint}";
    unless (-e $mntpoint) {
	eval { mkdir_p(dirname($mntpoint)) };
	#- do non-relative link for install, should be changed to relative link before rebooting
	symlink "/initrd/loopfs", $mntpoint;

	mkdir_p("/initrd/loopfs/lnx4win/boot");
	symlink "/initrd/loopfs/lnx4win/boot", "$prefix/boot";
    }
    #- indicate kernel to keep initrd
    mkdir_p("$prefix/initrd");
}


sub format_part {
    my ($part, $prefix) = @_;
    fs::mount_part($part->{loopback_device}, $prefix);
    create($part, $prefix);
    fs::real_format_part($part);
}

sub create {
    my ($part, $prefix) = @_;
    my $f = $part->{device} = "$prefix$part->{loopback_device}{mntpoint}$part->{loopback_file}";
    return if -e $f;

    eval { mkdir_p(dirname($f)) };

    log::l("creating loopback file $f ($part->{size} sectors)");

    my $block_size = 128;
    my $s = "\0" x (512 * $block_size);
    sysopen(my $F, $f, 2 | c::O_CREAT()) or die "failed to create loopback file";
    for (my $i = 0; $i < $part->{size}; $i += $block_size) {
	syswrite $F, $s or die "failed to create loopback file";
    }
}

sub getFree {
    my ($dir, $part) = @_;
    my $freespace = $dir ? 
      2 * (MDK::Common::System::df($dir))[1] : #- df in KiB
      $part->{size};

    $freespace - sum map { $_->{size} } @{$part->{loopback} || []};
}

#- returns the size of the loopback file if it already exists
#- returns -1 is the loopback file can't be used
sub verifFile {
    my ($dir, $file, $part) = @_;
    -e "$dir$file" and return -s "$dir$file";

    $_->{loopback_file} eq $file and return -1 foreach @{$part->{loopback} || []};

    undef;
}

sub prepare_boot() {
    my $r = readlink "$::prefix/boot"; 
    unlink "$::prefix/boot"; 
    mkdir_p("$::prefix/boot");
    [$r, $::prefix];
}

sub save_boot {
    my ($loop_boot, $prefix) = @{$_[0]};
    
    $loop_boot or return;

    my @files = glob_("$prefix/boot/*");
    cp_af(@files, $loop_boot) if @files;
    rm_rf("$prefix/boot");
    symlink $loop_boot, "$prefix/boot";
}


1;

alue='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Nicolas Vigier &lt;boklm@mars-attacks.org&gt;</td><td class='right'>2013-06-24 15:49:19 +0200</td></tr>
<tr><th>committer</th><td>Nicolas Vigier &lt;boklm@mars-attacks.org&gt;</td><td class='right'>2013-06-24 15:49:19 +0200</td></tr>
<tr><th>commit</th><td colspan='2' class='sha1'><a href='/software/infrastructure/mgagit/commit/?h=0.12&amp;id=3732abe657d773d461a92e14aa94678585a78ff2'>3732abe657d773d461a92e14aa94678585a78ff2</a> (<a href='/software/infrastructure/mgagit/patch/?id=3732abe657d773d461a92e14aa94678585a78ff2'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='sha1'><a href='/software/infrastructure/mgagit/tree/?h=0.12&amp;id=3732abe657d773d461a92e14aa94678585a78ff2'>3b952f180a9af119dee04c12110ca0bd21578250</a></td></tr>
<tr><th>parent</th><td colspan='2' class='sha1'><a href='/software/infrastructure/mgagit/commit/?h=0.12&amp;id=64566f582283e6de77d048496d6682957264e3cc'>64566f582283e6de77d048496d6682957264e3cc</a> (<a href='/software/infrastructure/mgagit/diff/?h=0.12&amp;id=3732abe657d773d461a92e14aa94678585a78ff2&amp;id2=64566f582283e6de77d048496d6682957264e3cc'>diff</a>)</td></tr><tr><th>download</th><td colspan='2' class='sha1'><a href='/software/infrastructure/mgagit/snapshot/mgagit-3732abe657d773d461a92e14aa94678585a78ff2.tar'>mgagit-3732abe657d773d461a92e14aa94678585a78ff2.tar</a><br/><a href='/software/infrastructure/mgagit/snapshot/mgagit-3732abe657d773d461a92e14aa94678585a78ff2.tar.gz'>mgagit-3732abe657d773d461a92e14aa94678585a78ff2.tar.gz</a><br/><a href='/software/infrastructure/mgagit/snapshot/mgagit-3732abe657d773d461a92e14aa94678585a78ff2.tar.bz2'>mgagit-3732abe657d773d461a92e14aa94678585a78ff2.tar.bz2</a><br/><a href='/software/infrastructure/mgagit/snapshot/mgagit-3732abe657d773d461a92e14aa94678585a78ff2.tar.xz'>mgagit-3732abe657d773d461a92e14aa94678585a78ff2.tar.xz</a><br/><a href='/software/infrastructure/mgagit/snapshot/mgagit-3732abe657d773d461a92e14aa94678585a78ff2.zip'>mgagit-3732abe657d773d461a92e14aa94678585a78ff2.zip</a><br/></td></tr></table>
<div class='commit-subject'>