From patchwork Fri Feb 19 16:50:43 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 10932 Received: (qmail 121737 invoked by alias); 19 Feb 2016 16:50:50 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 121720 invoked by uid 89); 19 Feb 2016 16:50:49 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RP_MATCHES_RCVD, SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=UD:1, 1008, Generate, ldconfig X-HELO: mx1.redhat.com Subject: Re: [PATCH] ldconfig: Do not remove stale symbolic links with -X [BZ #19610] To: "Carlos O'Donell" References: <56BC8790.1080400@redhat.com> <56BE25B4.3070806@redhat.com> Cc: GNU C Library From: Florian Weimer Message-ID: <56C747E3.9060902@redhat.com> Date: Fri, 19 Feb 2016 17:50:43 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <56BE25B4.3070806@redhat.com> On 02/12/2016 07:34 PM, Carlos O'Donell wrote: > At the design level: > - Comment for opt_link needs to change. Expand the comment on > line 103 in elf/ldconfig.c to describe in more detail that > symlinks are not created, and that neither are they removed > if they exist and are stale. Done. > - Use mktemp to create a temporary directory that exists instead > of using /opt which might be problematic. Thanks. I'm using the existing directory tree instead. I've added comments to the test explaining the relative vs absolute difference. New version attached. Florian 2016-02-19 Florian Weimer [BZ #19610] * elf/ldconfig.c (opt_link): Update comment. (options): Update help string for option -X. (search_dir): Unlink stale symbolic link only if updating symbolic links. * elf/tst-ldconfig-X.sh: New file. * elf/Makefile (tests-special): Add tst-ldconfig-X.out. (tst-ldconfig-X.out): New rule to run tst-ldconfig-X.sh. diff --git a/elf/Makefile b/elf/Makefile index 63a5355..ae99f65 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -163,7 +163,8 @@ endif endif ifeq ($(run-built-tests),yes) tests-special += $(objpfx)tst-leaks1-mem.out \ - $(objpfx)tst-leaks1-static-mem.out $(objpfx)noload-mem.out + $(objpfx)tst-leaks1-static-mem.out $(objpfx)noload-mem.out \ + $(objpfx)tst-ldconfig-X.out endif tlsmod17a-suffixes = 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 tlsmod18a-suffixes = 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 @@ -1252,3 +1253,7 @@ $(objpfx)tst-prelink-cmp.out: tst-prelink.exp \ $(objpfx)tst-prelink-conflict.out cmp $^ > $@; \ $(evaluate-test) + +$(objpfx)tst-ldconfig-X.out : tst-ldconfig-X.sh $(objpfx)ldconfig + $(SHELL) $< '$(common-objpfx)' '$(test-wrapper)' '$(test-wrapper-env)' > $@; \ + $(evaluate-test) diff --git a/elf/ldconfig.c b/elf/ldconfig.c index 9c6f2ba..467ca82 100644 --- a/elf/ldconfig.c +++ b/elf/ldconfig.c @@ -100,7 +100,8 @@ int opt_format = 1; /* Build cache. */ static int opt_build_cache = 1; -/* Generate links. */ +/* Enable symbolic link processing. If set, create or update symbolic + links, and remove stale symbolic links. */ static int opt_link = 1; /* Only process directories specified on the command line. */ @@ -141,7 +142,7 @@ static const struct argp_option options[] = { "print-cache", 'p', NULL, 0, N_("Print cache"), 0}, { "verbose", 'v', NULL, 0, N_("Generate verbose messages"), 0}, { NULL, 'N', NULL, 0, N_("Don't build cache"), 0}, - { NULL, 'X', NULL, 0, N_("Don't generate links"), 0}, + { NULL, 'X', NULL, 0, N_("Don't update symbolic links"), 0}, { NULL, 'r', N_("ROOT"), 0, N_("Change to and use ROOT as root directory"), 0}, { NULL, 'C', N_("CACHE"), 0, N_("Use CACHE as cache file"), 0}, { NULL, 'f', N_("CONF"), 0, N_("Use CONF as configuration file"), 0}, @@ -800,7 +801,7 @@ search_dir (const struct dir_entry *entry) error (0, errno, _("Cannot stat %s"), file_name); /* Remove stale symlinks. */ - if (strstr (direntry->d_name, ".so.")) + if (opt_link && strstr (direntry->d_name, ".so.")) unlink (real_file_name); continue; } diff --git a/elf/tst-ldconfig-X.sh b/elf/tst-ldconfig-X.sh new file mode 100644 index 0000000..07fd7d2 --- /dev/null +++ b/elf/tst-ldconfig-X.sh @@ -0,0 +1,63 @@ +#!/bin/sh +# Test that ldconfig -X does not remove stale symbolic links. +# Copyright (C) 2000-2016 Free Software Foundation, Inc. +# This file is part of the GNU C Library. + +# The GNU C Library is free software; you can redistribute it and/or +# modify it under the terms of the GNU Lesser General Public +# License as published by the Free Software Foundation; either +# version 2.1 of the License, or (at your option) any later version. + +# The GNU C Library is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +# Lesser General Public License for more details. + +# You should have received a copy of the GNU Lesser General Public +# License along with the GNU C Library; if not, see +# . + +set -ex + +common_objpfx=$1 +test_wrapper_env=$2 +run_program_env=$3 + +testroot="${common_objpfx}elf/bug19610-test-directory" +cleanup () { + rm -rf "$testroot" +} +trap cleanup 0 + +rm -rf "$testroot" +mkdir -p $testroot/lib $testroot/etc + +# Relative symbolic link target. +ln -s libdoesnotexist.so.1.1 $testroot/lib/libdoesnotexist.so.1 + +# Absolute symbolic link target. +ln -s $testroot/opt/sw/lib/libdoesnotexist2.so.1.1 $testroot/lib/ + +errors=0 +check_files () { + for name in libdoesnotexist.so.1 libdoesnotexist2.so.1.1 ; do + path="$testroot/lib/$name" + if test ! -h $path ; then + echo "error: missing file: $path" + errors=1 + fi + done +} + +check_files + +${test_wrapper_env} \ +${run_program_env} \ +${common_objpfx}elf/ldconfig -X -f /dev/null \ + -C $testroot/etc/ld.so.cache \ + $testroot/lib + +check_files + +exit $errors +