From fc5950e2eb1f9c0b7a1553f5717940d880e4853c Mon Sep 17 00:00:00 2001 From: Pascal Rigaux Date: Sat, 9 Oct 1999 13:26:41 +0000 Subject: no_comment --- perl-install/resize_fat/dir_entry.pm | 72 ++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) create mode 100644 perl-install/resize_fat/dir_entry.pm (limited to 'perl-install/resize_fat/dir_entry.pm') diff --git a/perl-install/resize_fat/dir_entry.pm b/perl-install/resize_fat/dir_entry.pm new file mode 100644 index 000000000..cfee23dae --- /dev/null +++ b/perl-install/resize_fat/dir_entry.pm @@ -0,0 +1,72 @@ +package resize_fat::dir_entry; + +use diagnostics; +use strict; + + +my $DELETED_FLAG = 0xe5; +my $VOLUME_LABEL_ATTR = 0x08; +my $VFAT_ATTR = 0x0f; +my $DIRECTORY_ATTR = 0x10; + +1; + +sub get_cluster($) { + my ($entry) = @_; + $entry->{first_cluster} + ($resize_fat::isFAT32 ? $entry->{first_cluster_high} * 65536 : 0); +} +sub set_cluster($$) { + my ($entry, $val) = @_; + $entry->{first_cluster} = $val & (1 << 16) - 1; + $entry->{first_cluster_high} = $val >> 16 if $resize_fat::isFAT32; +} + +sub is_directory_raw($) { + my ($entry) = @_; + !is_special_entry($entry) && $entry->{attributes} & $DIRECTORY_ATTR; +} + +sub is_directory($) { + my ($entry) = @_; + is_directory_raw($entry) && $entry->{name} !~ /^\.\.? /; +} + +sub is_volume($) { + my ($entry) = @_; + !is_special_entry($entry) && $entry->{attributes} & $VOLUME_LABEL_ATTR; +} + +sub is_file($) { + my ($entry) = @_; + !is_special_entry($entry) && !is_directory($entry) && !is_volume($entry) && $entry->{length}; +} + + +sub is_special_entry($) { + my ($entry) = @_; + my ($c) = unpack "C", $entry->{name}; + + #- skip empty slots, deleted files, and 0xF6?? (taken from kernel) + $c == 0 || $c == $DELETED_FLAG || $c == 0xF6 and return 1; + + $entry->{attributes} == $VFAT_ATTR and return 1; + 0; +} + + +#- return true if entry has been modified +sub remap { + my ($fat_remap, $entry) = @_; + + is_special_entry($entry) and return; + + my $cluster = get_cluster($entry); + my $new_cluster = $fat_remap->[$cluster]; + + #-print "remapping cluster ", get_first_cluster($fs, $entry), " to $new_cluster"; + + $new_cluster == $cluster and return; #- no need to modify + + set_cluster($entry, $new_cluster); + 1; +} -- cgit v1.2.1