summaryrefslogtreecommitdiffstats
path: root/perl-install/loopback.pm
blob: 8fd9c874870ffef265e47017b3671e5fc3b73fec (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
package loopback;

use diagnostics;
use strict;

#-######################################################################################
#- misc imports
#-######################################################################################
use common qw(:common :system :file :functional);
use partition_table qw(:types);
use commands;
use fs;
use log;


sub file {
    my ($part) = @_;
    ($part->{device}{mntpoint} || die "loopback::file but loopback file has no associated mntpoint") . 
      $part->{loopback_file};
}

sub loopbacks {
    map { map { @{$_->{loopback} || []} } partition_table::get_normal_parts($_) } @_;
}

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

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

    carryRootLoopback($part) or return;

    my $mntpoint = "$prefix$part->{mntpoint}";
    unless (-e $mntpoint) {
	eval { commands::mkdir_("-p", dirname($mntpoint)) };
	#- do non-relative link for install, should be changed to relative link before rebooting
	symlink "/initrd/loopfs", $mntpoint;
    }
    #- indicate kernel to keep initrd
    mkdir "$prefix/initrd", 0755;
}


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

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

    eval { commands::mkdir_("-p", dirname($f)) };

    log::l("creating loopback file $f");
    
    local *F;
    open F, ">$f" or die "failed to create loopback file";
    for (my $nb = $part->{size}; $nb >= 0; $nb -= 8) { #- 8 * 512 = 4096 :)
	print F "\0" x 4096;
    }
    $f;
}

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

    isMountableRW($part) or return;

    my $dir = "/tmp/loopback_tmp";

    if ($part->{isMounted}) {
	$dir = ($prefix || '') . $part->{mntpoint};
    } elsif ($part->{notFormatted} && !$part->{isFormatted}) {
	$dir = '';
    } else {
	mkdir $dir, 0700;
	fs::mount($part->{device}, $dir, type2fs($part->{type}), 'rdonly');
    }
    my $h = before_leaving {
	if (!$part->{isMounted} && $dir) {
	    fs::umount($dir);
	    unlink($dir)
	}
    };
    $h->{dir} = $dir;
    $h;
}

sub getFree {
    my ($dir, $part) = @_;
    my ($freespace);

    if ($dir) {
	my $buf = ' ' x 20000;
	syscall_('statfs', $dir, $buf) or return;
	my (undef, $blocksize, $size, undef, $free, undef) = unpack "L2L4", $buf;
	$_ *= $blocksize / 512 foreach $free;
	
	$freespace = $free;
    } else {
	$freespace = $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;
}


1;