From owner-svn-src-head@freebsd.org Fri Jul 27 15:35:50 2018 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 6F40B104E99C for ; Fri, 27 Jul 2018 15:35:50 +0000 (UTC) (envelope-from ian@freebsd.org) Received: from pmta2.delivery6.ore.mailhop.org (pmta2.delivery6.ore.mailhop.org [54.200.129.228]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id E76457A578 for ; Fri, 27 Jul 2018 15:35:49 +0000 (UTC) (envelope-from ian@freebsd.org) X-MHO-RoutePath: aGlwcGll X-MHO-User: b82a7eea-91b2-11e8-904b-1d2e466b3c59 X-Report-Abuse-To: https://support.duocircle.com/support/solutions/articles/5000540958-duocircle-standard-smtp-abuse-information X-Originating-IP: 67.177.211.60 X-Mail-Handler: DuoCircle Outbound SMTP Received: from ilsoft.org (unknown [67.177.211.60]) by outbound2.ore.mailhop.org (Halon) with ESMTPSA id b82a7eea-91b2-11e8-904b-1d2e466b3c59; Fri, 27 Jul 2018 15:35:42 +0000 (UTC) Received: from rev (rev [172.22.42.240]) by ilsoft.org (8.15.2/8.15.2) with ESMTP id w6RFZfQK023737; Fri, 27 Jul 2018 09:35:41 -0600 (MDT) (envelope-from ian@freebsd.org) Message-ID: <1532705741.61594.53.camel@freebsd.org> Subject: Re: svn commit: r336746 - in head/lib: libc/gen libutil From: Ian Lepore To: Konstantin Belousov Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Date: Fri, 27 Jul 2018 09:35:41 -0600 In-Reply-To: <20180727150304.GA2489@kib.kiev.ua> References: <201807261834.w6QIYc9i080738@repo.freebsd.org> <20180727150304.GA2489@kib.kiev.ua> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.18.5.1 FreeBSD GNOME Team Port Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 27 Jul 2018 15:35:50 -0000 On Fri, 2018-07-27 at 18:03 +0300, Konstantin Belousov wrote: > On Thu, Jul 26, 2018 at 06:34:38PM +0000, Ian Lepore wrote: > > > > Author: ian > > Date: Thu Jul 26 18:34:38 2018 > > New Revision: 336746 > > URL: https://svnweb.freebsd.org/changeset/base/336746 > > > > Log: > >   Make pw_scan(3) more compatible with getpwent(3) et. al. when processing > >   data from /etc/passwd rather than /etc/master.passwd. > >    > >   The libc getpwent(3) and related functions automatically read master.passwd > >   when run by root, or passwd when run by a non-root user.  When run by non- > >   root, getpwent() copes with the missing data by setting the corresponding > >   fields in the passwd struct to known values (zeroes for numbers, or a > >   pointer to an empty string for literals).  When libutil's pw_scan(3) was > >   used to parse a line without the root-accessible data, it was leaving > >   garbage in the corresponding fields. > >    > >   These changes rename the static pw_init() function used by getpwent() and > >   friends to __pw_initpwd(), and move it into pw_scan.c so that common init > >   code can be shared between libc and libutil.  pw_scan(3) now calls > >   __pw_initpwd() before __pw_scan(), just like the getpwent() family does, so > >   that reading an arbitrary passwd file in either format and parsing it with > >   pw_scan(3) returns the same results as getpwent(3) would. > >    > >   This also adds a new pw_initpwd(3) function to libutil, so that code which > >   creates passwd structs from scratch in some manner that doesn't involve > >   pw_scan() can initialize the struct to the values expected by lots of > >   existing code, which doesn't expect to encounter NULL pointers or garbage > >   values in some fields. > > > If my reading is right, you just made libutil depend on the internal > libc interfaces. Formal consequence is that libutil.so version must > be bumped each time the used interface is changed (and it is allowed > to change). I think that your change actually requires the bump of > libutil.so.N version already. > > Also, libutil.so.N should be moved from the libutil pkgbase package to > the clibs package, I am not sure about this. > > At the higher level, I very much dislike this change. FBSDprivate_1.0 > namespace is for symbols providing the internal interfaces for the > C runtime implementation in the FreeBSD. This is mostly a knot of > inter-dependencies between rtld, libc and libthr. libutil arguably > should not participate. > > If you want for libc to provide a functionality outside the C runtime, > please make the sustainable interface, which ABI can be maintained, and > export the symbols in the normal namespace, with the usual stability > guarantees. There was already a function, __pw_scan(), in file pw_scan.c, which was called from both libutil and libc implementations. I added a new function __pw_initpwd() into the pw_scan.c file. That function is called from all the same places that __pw_scan() is called from. So as near as I can tell, I haven't changed the structure of anything or created any new linkages between the libraries that didn't exist already. I will admit I don't understand the FBSDprivate_1.0 stuff at all, and there appears to be no documentation or guidance on how to work with it. Since __pw_scan was in the private list, and I was adding a new function that is like it in every way, I reasoned that the new function should be in the list too. It's actually not clear to me that either of the functions should be in that list, but like I said... no published info about it that I could find. I also noticed that chpass(1) and pwd_mkdb(8)_both directly compile in their own copy of the pw_scan.c source using .PATH in their makefiles. I wonder if doing that as the way of sharing the code between libc and libutil would be a better thing to do? (And presumably that would remove the need to have entries in the FBSDprivate_1.0 list?) -- Ian