diff options
Diffstat (limited to 'perl-install/resize_fat/fat.pm')
| -rw-r--r-- | perl-install/resize_fat/fat.pm | 167 |
1 files changed, 0 insertions, 167 deletions
diff --git a/perl-install/resize_fat/fat.pm b/perl-install/resize_fat/fat.pm deleted file mode 100644 index e6039077a..000000000 --- a/perl-install/resize_fat/fat.pm +++ /dev/null @@ -1,167 +0,0 @@ -package resize_fat::fat; - -use diagnostics; -use strict; - -use resize_fat::any; -use resize_fat::io; - -1; - -sub read($) { - my ($fs) = @_; - - @{$fs->{fats}} = map { - my $fat = eval { resize_fat::io::read($fs, $fs->{fat_offset} + $_ * $fs->{fat_size}, $fs->{fat_size}) }; - $@ and die "reading fat #$_ failed"; - vec($fat, 0, 8) == $fs->{media} or die "FAT $_ has invalid signature"; - $fat; - } (0 .. $fs->{nb_fats} - 1); - - $fs->{fat} = $fs->{fats}[0]; - - my ($free, $bad, $used) = (0, 0, 0); - - for (my $i = 2; $i < $fs->{nb_clusters} + 2; $i++) { - my $cluster = &next($fs, $i); - if ($cluster == 0) { $free++; } - elsif ($cluster == $resize_fat::bad_cluster_value) { $bad++; } - else { $used++; } - } - @{$fs->{clusters}{count}}{qw(free bad used)} = ($free, $bad, $used); -} - -sub write($) { - my ($fs) = @_; - - sysseek $fs->{fd}, $fs->{fat_offset}, 0 or die "write_fat: seek failed"; - foreach (1..$fs->{nb_fats}) { - syswrite $fs->{fd}, $fs->{fat} or die "write_fat: write failed"; - } -} - - - -#- allocates where all the clusters will be moved to. Clusters before cut_point -#- remain in the same position, however cluster that are part of a directory are -#- moved regardless (this is a mechanism to prevent data loss) (cut_point is the -#- first cluster that won't occur in the new fs) -sub allocate_remap { - my ($fs, $cut_point) = @_; - my ($cluster, $new_cluster); - my $remap = sub { $fs->{fat_remap}[$cluster] = $new_cluster; }; - my $get_new = sub { - $new_cluster = get_free($fs); - 0 < $new_cluster && $new_cluster < $cut_point or die "no free clusters"; - set_eof($fs, $new_cluster); #- mark as used - #-log::ld("resize_fat: [$cluster,", &next($fs, $cluster), "...]->$new_cluster..."); - }; - - $fs->{fat_remap}[0] = 0; - $fs->{last_free_cluster} = 2; - for ($cluster = 2; $cluster < $fs->{nb_clusters} + 2; $cluster++) { - if ($cluster < $cut_point) { - if ($fs->{fat_flag_map}[$cluster] == $resize_fat::any::DIRECTORY) { - &$get_new(); - } else { - $new_cluster = $cluster; - } - &$remap(); - } elsif (!is_empty(&next($fs, $cluster))) { - &$get_new(); - &$remap(); - } - } -} - - -#- updates the fat for the resized filesystem -sub update { - my ($fs) = @_; - - for (my $cluster = 2; $cluster < $fs->{nb_clusters} + 2; $cluster++) { - if ($fs->{fat_flag_map}[$cluster]) { - my $old_next = &next($fs, $cluster); - my $new = $fs->{fat_remap}[$cluster]; - my $new_next = $fs->{fat_remap}[$old_next]; - - set_available($fs, $cluster); - - is_eof($old_next) ? - set_eof($fs, $new) : - set_next($fs, $new, $new_next); - } - } -} - - -#- - compares the two FATs (one's a backup that should match) - skips first entry -#- - its just a signature (already checked above) NOTE: checks for cross-linking -#- are done in count.c -sub check($) { - my ($fs) = @_; - foreach (@{$fs->{fats}}) { - $_ eq $fs->{fats}[0] or die "FAT tables do not match"; - } -} - -sub endianness16($) { (($_[0] & 0xff) << 8) + ($_[0] >> 8); } -sub endianness($$) { - my ($val, $nb_bits) = @_; - my $r = 0; - for (; $nb_bits > 0; $nb_bits -= 8) { - $r <<= 8; - $r += $val & 0xff; - $val >>= 8; - } - $nb_bits < 0 and die "error: endianness only handle numbers divisible by 8"; - $r; -} - -sub next($$) { - my ($fs, $cluster) = @_; - $cluster > $fs->{nb_clusters} + 2 and die "fat::next: cluster $cluster outside filesystem"; - endianness(vec($fs->{fat}, $cluster, $fs->{fs_type_size}), $fs->{fs_type_size}); - -} -sub set_next($$$) { - my ($fs, $cluster, $new_v) = @_; - $cluster > $fs->{nb_clusters} + 2 and die "fat::set_next: cluster $cluster outside filesystem"; - vec($fs->{fat}, $cluster, $fs->{fs_type_size}) = endianness($new_v, $fs->{fs_type_size}); -} - - -sub get_free($) { - my ($fs) = @_; - foreach (my $i = 0; $i < $fs->{nb_clusters}; $i++) { - my $cluster = ($i + $fs->{last_free_cluster} - 2) % $fs->{nb_clusters} + 2; - is_available(&next($fs, $cluster)) and return $fs->{last_free_cluster} = $cluster; - } - die "no free clusters"; -} - -#- returns true if <cluster> represents an EOF marker -sub is_eof($) { - my ($cluster) = @_; - $cluster >= $resize_fat::bad_cluster_value; -} -sub set_eof($$) { - my ($fs, $cluster) = @_; - set_next($fs, $cluster, $resize_fat::bad_cluster_value + 1); -} - -#- returns true if <cluster> is empty. Note that this includes bad clusters. -sub is_empty($) { - my ($cluster) = @_; - $cluster == 0 || $cluster == $resize_fat::bad_cluster_value; -} - -#- returns true if <cluster> is available. -sub is_available($) { - my ($cluster) = @_; - $cluster == 0; -} -sub set_available($$) { - my ($fs, $cluster) = @_; - set_next($fs, $cluster, 0); -} |