From 775477aa1da94cb9fb9b9afdc217231a0cd42ac1 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Date: Tue, 1 May 2007 23:42:44 +0200
Subject: [PATCH] Teach import-tars about GNU tar's @LongLink extension.
This extension allows GNU tar to process file names in excess of the 100
characters defined by the original tar standard. It does this by faking a
file, named '././@LongLink' containing the true file name, and then adding
the file with a truncated name. The idea is that tar without this
extension will write out a file with the long file name, and write the
contents into a file with truncated name.
Unfortunately, GNU tar does a lousy job at times. When truncating results
in a _directory_ name, it will happily use _that_ as a truncated name for
the file.
An example where this actually happens is gcc-4.1.2, where the full path
of the file WeThrowThisExceptionHelper.java truncates _exactly_ before the
basename. So, we have to support that ad-hoc extension.
This bug was noticed by Chris Riddoch on IRC.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
---
contrib/fast-import/import-tars.perl | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/contrib/fast-import/import-tars.perl b/contrib/fast-import/import-tars.perl
index 82a90429c8e..e46492048c7 100755
--- a/contrib/fast-import/import-tars.perl
+++ b/contrib/fast-import/import-tars.perl
@@ -52,6 +52,25 @@ foreach my $tar_file (@ARGV)
Z8 Z1 Z100 Z6
Z2 Z32 Z32 Z8 Z8 Z*', $_;
last unless $name;
+ if ($name eq '././@LongLink') {
+ # GNU tar extension
+ if (read(I, $_, 512) != 512) {
+ die ('Short archive');
+ }
+ $name = unpack 'Z257', $_;
+ next unless $name;
+
+ my $dummy;
+ if (read(I, $_, 512) != 512) {
+ die ('Short archive');
+ }
+ ($dummy, $mode, $uid, $gid, $size, $mtime,
+ $chksum, $typeflag, $linkname, $magic,
+ $version, $uname, $gname, $devmajor, $devminor,
+ $prefix) = unpack 'Z100 Z8 Z8 Z8 Z12 Z12
+ Z8 Z1 Z100 Z6
+ Z2 Z32 Z32 Z8 Z8 Z*', $_;
+ }
next if $name =~ m{/\z};
$mode = oct $mode;
$size = oct $size;