Jim Meyering <[email protected]> writes: Thanks again for your notes. I amended them into the patch.
Cheers, Giuseppe >From 3f0f5744899afc15e69554220be836f673b1dad3 Mon Sep 17 00:00:00 2001 From: Giuseppe Scrivano <[email protected]> Date: Tue, 20 Oct 2009 10:49:17 +0200 Subject: [PATCH] tests: add a new test that checks for a possible `tail' race. If new data is available between the initial read and tail registers the inotify watch descriptors, ensure that it is read before a new event happens on the file. * tests/Makefile.am (TESTS): Add tail-2/inotify-race. * tests/tail-2/inotify-race: New file. --- tests/Makefile.am | 1 + tests/tail-2/inotify-race | 69 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 70 insertions(+), 0 deletions(-) create mode 100755 tests/tail-2/inotify-race diff --git a/tests/Makefile.am b/tests/Makefile.am index 751db1c..bb11c23 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -74,6 +74,7 @@ EXTRA_DIST += $(TESTS) TESTS = \ misc/help-version \ + tail-2/inotify-race \ misc/invalid-opt \ rm/ext3-perf \ rm/cycle \ diff --git a/tests/tail-2/inotify-race b/tests/tail-2/inotify-race new file mode 100755 index 0000000..47129db --- /dev/null +++ b/tests/tail-2/inotify-race @@ -0,0 +1,69 @@ +#!/bin/sh +# Copyright (C) 2006, 2009 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +# 02110-1301, USA. + + +# Ensure that tail does not ignore data that is appended to a tailed-forever +# file between tail's initial read-to-EOF, and when the inotify watches +# are established in tail_forever_inotify. That data could be ignored +# indefinitely if no *other* data is appended, but it would be printed as +# soon as any additional appended data is detected. + +if test "$VERBOSE" = yes; then + set -x + tail --version +fi + +. $srcdir/test-lib.sh + +fail=0 + +touch file || framework_failure +touch tail.out || framework_failure + +( gdb --version ) > gdb.out 2>&1 +case $(cat gdb.out) in + 'GNU gdb'*) ;; + *) skip_test_ "can't run gdb";; +esac + + +# See if gdb works: + +gdb -nx --batch-silent \ + --eval-command='break tail_forever_inotify' \ + --eval-command='run -f file' \ + --eval-command='quit' \ + $abs_top_builddir/src/tail < /dev/null > gdb.out 2>&1 + +test -s gdb.out && skip_test_ "can't set breakpoints in tail" + + +timeout 10s gdb -nx --batch-silent \ + --eval-command='break tail_forever_inotify' \ + --eval-command='run -f file >> tail.out' \ + --eval-command="shell echo never-seen-with-tail-7.5 >> file" \ + --eval-command='continue' \ + --eval-command='quit' \ + $abs_top_builddir/src/tail < /dev/null & +pid=$! + +tail --pid=$pid -f tail.out | (read; kill $pid) + +test -s tail.out || fail=1 + +Exit $fail -- 1.6.3.3
