From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id bv08IRI+YmDcUwAAWB0awg (envelope-from ) for ; Mon, 29 Mar 2021 16:52:34 -0400 Received: by simark.ca (Postfix, from userid 112) id 79A8B1E965; Mon, 29 Mar 2021 16:52:34 -0400 (EDT) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id 903A01E590 for ; Mon, 29 Mar 2021 16:52:33 -0400 (EDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id D8D41385781D; Mon, 29 Mar 2021 20:52:32 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D8D41385781D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1617051152; bh=F9bZcXJMy5yBAE9NqbyvA1x8/LGM6zhiuR5LwdVb/r4=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:Cc:From; b=erlEMNP9UwYpMMiWL0QZ3jbTkFm26jnhxDSfVDcKpRhg3h6xb+tvM4+0hkrNowSNc rKzWI3d+av9LU0WqmIBnqofCHtkC/Wsm2JwUmnUaDu5tgI4vB+L06R6AnrD1QKGIbb 3wF3d3/t6MHZsdB9qIMQu5qnMADFf++CGA11mdcM= Received: from lndn.lancelotsix.com (lndn.lancelotsix.com [51.195.220.111]) by sourceware.org (Postfix) with ESMTPS id BEDEC385781D for ; Mon, 29 Mar 2021 20:52:29 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org BEDEC385781D Received: from Plymouth.lan (unknown [IPv6:2a02:390:9086:0:610f:effd:be2a:1f29]) by lndn.lancelotsix.com (Postfix) with ESMTPSA id 8A7FE818C3; Mon, 29 Mar 2021 20:52:28 +0000 (UTC) To: gdb-patches@sourceware.org Subject: [PATCH v4] [PR gdb/27614] gdb-add-index fails on symlinks. Date: Mon, 29 Mar 2021 21:52:24 +0100 Message-Id: <20210329205224.12859-1-lsix@lancelotsix.com> X-Mailer: git-send-email 2.30.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.11 (lndn.lancelotsix.com [0.0.0.0]); Mon, 29 Mar 2021 20:52:28 +0000 (UTC) X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Lancelot SIX via Gdb-patches Reply-To: Lancelot SIX Cc: Lancelot SIX Errors-To: gdb-patches-bounces@sourceware.org Sender: "Gdb-patches" Since V3: - Do net rely on GDB's maintenance commands to resolve symlinks, revert to using readlink while maximizing portability. Since V2: - Use GDB to follow symlink instead of readlink. Unlike readlink, GDB is guaranteed to be available. Since V1: - Replace '&>/dev/null' with '>/dev/null 2>&1' -- PR 27614 shows that gdb-add-index fails to generate the index when its argument is a symlink. The following one liner illustrates the reported problem: $ echo 'int main(){}'|gcc -g -x c -;ln -s a.out symlink;gdb-add-index symlink gdb-add-index: No index was created for symlink gdb-add-index: [Was there no debuginfo? Was there already an index?] $ ls -l -rwxr-xr-x 1 25712 Mar 19 23:05 a.out* -rw------- 1 8277 Mar 19 23:05 a.out.gdb-index lrwxrwxrwx 1 5 Mar 19 23:05 symlink -> a.out* GDB generates the .gdb-index file with a name that matches the name of the actual program (a.out.gdb-index here), not the symlink that references it. The remaining of the script is looking for a file named after the provided argument (would be 'symlink.gdb-index' in our example). gdb/ChangeLog: PR gdb/27614 * contrib/gdb-add-index.sh: Fix when called with a symlink as an argument. gdb/testsuite/ChangeLog: PR gdb/27614 * gdb.dwarf2/gdb-add-index-symlink.exp: New test. --- gdb/contrib/gdb-add-index.sh | 28 +++++++++++ .../gdb.dwarf2/gdb-add-index-symlink.exp | 47 +++++++++++++++++++ 2 files changed, 75 insertions(+) create mode 100644 gdb/testsuite/gdb.dwarf2/gdb-add-index-symlink.exp diff --git a/gdb/contrib/gdb-add-index.sh b/gdb/contrib/gdb-add-index.sh index 2ac3fddbf26..734110caa3b 100755 --- a/gdb/contrib/gdb-add-index.sh +++ b/gdb/contrib/gdb-add-index.sh @@ -37,6 +37,34 @@ fi file="$1" +if test -L "$file"; then + if ! command -v readlink >/dev/null 2>&1; then + echo "$myname: 'readlink' missing. Failed to follow symlink $1." 1>&2 + exit 1 + fi + + # Count number of links followed in order to detect loops. + count=0 + while test -L "$file"; do + target=$(readlink "$file") + + case "$target" in + /*) + file="$target" + ;; + *) + file="$(dirname "$file")/$target" + ;; + esac + + count="$((count + 1))" + if test "$count" -gt 10; then + echo "$myname: Detected loop while following link $file" + exit 1 + fi + done +fi + if test ! -r "$file"; then echo "$myname: unable to access: $file" 1>&2 exit 1 diff --git a/gdb/testsuite/gdb.dwarf2/gdb-add-index-symlink.exp b/gdb/testsuite/gdb.dwarf2/gdb-add-index-symlink.exp new file mode 100644 index 00000000000..eaeddec0250 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/gdb-add-index-symlink.exp @@ -0,0 +1,47 @@ +# Copyright 2021 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +load_lib dwarf.exp + +# This test can only be run on targets which support DWARF-2. +if {![dwarf2_support]} { + return 0 +} + +standard_testfile main.c + +if { [prepare_for_testing "failed to prepare" "${testfile}" \ + [list ${srcfile}]] } { + return -1 +} + +set symlink [file dirname $binfile]/symlink + +if { ![file exists $symlink] } { + file link -symbolic $symlink $binfile +} + +if { [ensure_gdb_index $symlink] == -1 } { + fail "Unable to call gdb-add-index with a symlink to a symfile" + return -1 +} + +# Ok, we have a copy of $binfile with an index. +# Restart gdb and verify the index was used. + +clean_restart $symlink +gdb_test "mt print objfiles ${testfile}" \ + "(gdb_index|debug_names).*" \ + "index used" -- 2.30.1