From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f41.google.com ([209.85.128.41]) by ewsd; Fri Sep 14 22:57:10 EDT 2018 Received: by mail-wm1-f41.google.com with SMTP id o18-v6so3795846wmc.0 for <9front@9front.org>; Fri, 14 Sep 2018 19:57:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=offblast-org.20150623.gappssmtp.com; s=20150623; h=mime-version:from:date:message-id:subject:to; bh=tKVi6UDYiklaGQ2OiBXO1Nz81Bpk3SBzj/4JTpp4L6Q=; b=HB629OH/HEWBD7P9yxGSBxLbkeRgmEn0GlA1rQmkOSEHiLJ+Bn55ALDWRaF8a8Pa+B kzjazEapvLKRnYvkKBRr9IIynlzJpLdbXDX65KnAwIbPKV/amqCavCgv0+bAVZ8GtmRG KrMnaHp3ZMii/pElusfVrPfam+vRoFCeHoZ0fVohAKTlvh7YWg7ZMtpTV7LR1stFEwSW FHFL5mHy06zQ553lAIwvrypt3aY7A+lUsVPbXhRmlo1oQzJ7z3Fysooxo0LAMoRX4HXK H22xKjUBSQA7md9LEvymTAWvVqwXLxP9yCyUtE0WMruCJlh1Y3d63aJyqmIGiCjVgmW7 fLQQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=tKVi6UDYiklaGQ2OiBXO1Nz81Bpk3SBzj/4JTpp4L6Q=; b=A06C47073qezGzbAiww8D/y/L/NJyEUi1N2j1rcyLI4olclF+Zk2YzJ4NYf1vy5O3M l8PTTG0qKNZZ51tiBnIM11Od0XCSl4KV8M6PwAPrGMcqBE6y4hTcyu55E06/tZuh5KbA imovqmEf1YVcV8Mpj3XMwGCqw9ofLI/XjcPvFZRXmJNEVGyBhss2LUmMb3NuHMvKvt8l x4LwlTVRHYCh5IOWRPqSjDDLm7bQZLb986TGtIyCHBVayAfFhN4vP3F/SYv9L5NteYIf 9U77PFkAEnwm1wiBZpKqJojD88P93GsX3PYYi9FJMWSduhPhc+aYdyXB8gfYu8lO44NF 5guw== X-Gm-Message-State: APzg51D88S4FWQPF/Pbxdp09tl/gBL3EWe1wqxLje66Cy27um2eShbjx IHAUPs9PbrLezjrCnWV93dArgDqMr7tTJYyCmRkYsi3nLL8= X-Google-Smtp-Source: ANB0VdbyxMTWF41U4hhcujZ15az4ALUQytk8BWVkeuzLQmi/csaOFztPA4UJnXQm+pqPVukvE8+Yp7qMmzAhZQm7Sj0= X-Received: by 2002:a1c:1510:: with SMTP id 16-v6mr4317216wmv.74.1536980223338; Fri, 14 Sep 2018 19:57:03 -0700 (PDT) MIME-Version: 1.0 From: Nick Owens Date: Fri, 14 Sep 2018 19:56:52 -0700 Message-ID: Subject: bug: tar doesnt understand pax extended headers To: 9front@9front.org Content-Type: multipart/mixed; boundary="0000000000003d4fae0575e018df" List-ID: <9front.9front.org> List-Help: X-Glyph: ➈ X-Bullshit: asynchronous standard-aware GPU control --0000000000003d4fae0575e018df Content-Type: text/plain; charset="UTF-8" tar(1) doesn't understand pax extended headers. attached is a patch which will simply ignore pax headers. see http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html for a description of the headers and their format. in the above documentation the type is referred to by 'typeflag', and in tar.c, linkflag. pax extended headers have two types, 'x' and 'g'. the main thing that these seem to be useful for are file names which are longer than whats normally representable. right now, tar(1) will treat these pax extended headers as normal "files" and extract the headers to disk, cluttering the fs. for now we could simply ignore them (easy), but it would be ideal to read them to find the long path names. the only trouble with this is that one needs to parse all of the pax 'size key=value\n' attributes in the pax extended header, finding the 'path' key and using its value as the new path. there's already some provision for this in tar.c's "getname" function. there's also no fixed size for these pax attributes, so filenames can (in theory) be of unlimited length. if anyone wants to pick this up, the "archive/tar" package in go seems like a decent reference. --0000000000003d4fae0575e018df Content-Type: text/x-patch; charset="US-ASCII"; name="tar.c.patch" Content-Disposition: attachment; filename="tar.c.patch" Content-Transfer-Encoding: base64 Content-ID: X-Attachment-Id: f_jm2ubgn70 ZGlmZiAtLWdpdCBhL3N5cy9zcmMvY21kL3Rhci5jIGIvc3lzL3NyYy9jbWQvdGFyLmMKLS0tIGEv c3lzL3NyYy9jbWQvdGFyLmMKKysrIGIvc3lzL3NyYy9jbWQvdGFyLmMKQEAgLTc4LDYgKzc4LDgg QEAgZW51bSB7CiAKIAlMRl9MT05HTkFNRSA9CSdMJywJCS8qIEdOVSBleHRlbnN0aW9uICovCiAJ TEZfTE9OR0xJTksgPSAJJ0snLAorCUxGX1BBWFgJCT0JJ3gnLAorCUxGX1BBWEcJCT0JJ2cnLAog fTsKIAogI2RlZmluZSBpc2xpbmsobGYpCShpc3JlYWxsaW5rKGxmKSB8fCBpc3N5bWxpbmsobGYp KQpAQCAtMTA2MSw2ICsxMDYzLDkgQEAgb3BlbmZuYW1lKEhkciAqaHAsIGNoYXIgKmZuYW1lLCBp bnQgZGlyLAogCWNhc2UgTEZfRklGTzoKIAkJZnByaW50KDIsICIlczogY2FuJ3QgbWFrZSBmaWZv ICVzXG4iLCBhcmd2MCwgZm5hbWUpOwogCQlicmVhazsKKwljYXNlIExGX1BBWFg6CisJY2FzZSBM Rl9QQVhHOgorCQlicmVhazsKIAlkZWZhdWx0OgogCQlpZiAoIWtlZXBleGlzdGluZyB8fCBhY2Nl c3MoZm5hbWUsIEFFWElTVCkgPCAwKSB7CiAJCQlpbnQgcncgPSAoZGlyPyBPUkVBRDogT1dSSVRF KTsK --0000000000003d4fae0575e018df--