diff options
-rw-r--r-- | NEWS | 4 | ||||
-rw-r--r-- | src/tail.c | 63 | ||||
-rw-r--r-- | tests/Makefile.am | 1 | ||||
-rwxr-xr-x | tests/tail-2/F-vs-missing | 49 | ||||
-rwxr-xr-x | tests/tail-2/F-vs-rename | 35 | ||||
-rwxr-xr-x | tests/tail-2/inotify-hash-abuse | 27 | ||||
-rwxr-xr-x | tests/tail-2/wait | 2 |
7 files changed, 130 insertions, 51 deletions
@@ -21,6 +21,10 @@ GNU coreutils NEWS -*- outline -*- tac would perform a double-free when given an input line longer than 16KiB. [bug introduced in coreutils-8.3] + tail -F once again notices changes in a currently unavailable directory, + and works around a Linux kernel bug where inotify runs out of resources. + [bugs introduced in coreutils-7.5] + tr now consistently handles case conversion character classes. In some locales, valid conversion specifications caused tr to abort, while in all locales, some invalid specifications were undiagnosed. diff --git a/src/tail.c b/src/tail.c index 75e9d53e3..68cc819d6 100644 --- a/src/tail.c +++ b/src/tail.c @@ -1300,9 +1300,10 @@ check_fspec (struct File_spec *fspec, int wd, int *prev_wd) error (EXIT_FAILURE, errno, _("write error")); } -/* Tail N_FILES files forever, or until killed. - Check modifications using the inotify events system. */ -static void +/* Attempt to tail N_FILES files forever, or until killed. + Check modifications using the inotify events system. + Return false on error, or true to revert to polling. */ +static bool tail_forever_inotify (int wd, struct File_spec *f, size_t n_files, double sleep_interval) { @@ -1311,7 +1312,9 @@ tail_forever_inotify (int wd, struct File_spec *f, size_t n_files, /* Map an inotify watch descriptor to the name of the file it's watching. */ Hash_table *wd_to_name; - bool found_watchable = false; + bool found_watchable_file = false; + bool found_unwatchable_dir = false; + bool no_inotify_resources = false; bool writer_is_dead = false; int prev_wd; size_t evlen = 0; @@ -1355,9 +1358,15 @@ tail_forever_inotify (int wd, struct File_spec *f, size_t n_files, if (f[i].parent_wd < 0) { - error (0, errno, _("cannot watch parent directory of %s"), - quote (f[i].name)); - continue; + if (errno != ENOSPC) /* suppress confusing error. */ + error (0, errno, _("cannot watch parent directory of %s"), + quote (f[i].name)); + else + error (0, 0, _("inotify resources exhausted")); + found_unwatchable_dir = true; + /* We revert to polling below. Note invalid uses + of the inotify API will still be diagnosed. */ + break; } } @@ -1365,7 +1374,12 @@ tail_forever_inotify (int wd, struct File_spec *f, size_t n_files, if (f[i].wd < 0) { - if (errno != f[i].errnum) + if (errno == ENOSPC) + { + no_inotify_resources = true; + error (0, 0, _("inotify resources exhausted")); + } + else if (errno != f[i].errnum) error (0, errno, _("cannot watch %s"), quote (f[i].name)); continue; } @@ -1373,12 +1387,22 @@ tail_forever_inotify (int wd, struct File_spec *f, size_t n_files, if (hash_insert (wd_to_name, &(f[i])) == NULL) xalloc_die (); - found_watchable = true; + found_watchable_file = true; } } - if (follow_mode == Follow_descriptor && !found_watchable) - return; + /* Linux kernel 2.6.24 at least has a bug where eventually, ENOSPC is always + returned by inotify_add_watch. In any case we should revert to polling + when there are no inotify resources. Also a specified directory may not + be currently present or accessible, so revert to polling. */ + if (no_inotify_resources || found_unwatchable_dir) + { + /* FIXME: release hash and inotify resources allocated above. */ + errno = 0; + return true; + } + if (follow_mode == Follow_descriptor && !found_watchable_file) + return false; prev_wd = f[n_files - 1].wd; @@ -2140,16 +2164,18 @@ main (int argc, char **argv) When follow_mode == Follow_name we would ideally like to detect that. Note if there is a change to the original file then we'll recheck it and follow the new file, or ignore it if the - file has changed to being remote. */ + file has changed to being remote. + + FIXME: when using inotify, and a directory for a watched file + is recreated, then we don't recheck any new file when + follow_mode == Follow_name */ if (tailable_stdin (F, n_files) || any_remote_file (F, n_files)) disable_inotify = true; if (!disable_inotify) { int wd = inotify_init (); - if (wd < 0) - error (0, errno, _("inotify cannot be used, reverting to polling")); - else + if (0 <= wd) { /* Flush any output from tail_file, now, since tail_forever_inotify flushes only after writing, @@ -2157,11 +2183,10 @@ main (int argc, char **argv) if (fflush (stdout) != 0) error (EXIT_FAILURE, errno, _("write error")); - tail_forever_inotify (wd, F, n_files, sleep_interval); - - /* The only way the above returns is upon failure. */ - exit (EXIT_FAILURE); + if (!tail_forever_inotify (wd, F, n_files, sleep_interval)) + exit (EXIT_FAILURE); } + error (0, errno, _("inotify cannot be used, reverting to polling")); } #endif tail_forever (F, n_files, sleep_interval); diff --git a/tests/Makefile.am b/tests/Makefile.am index a6a0594b8..41e0cbce7 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -84,6 +84,7 @@ TESTS = \ cp/link-heap \ tail-2/inotify-hash-abuse \ tail-2/inotify-hash-abuse2 \ + tail-2/F-vs-missing \ tail-2/F-vs-rename \ tail-2/inotify-rotate \ chmod/no-x \ diff --git a/tests/tail-2/F-vs-missing b/tests/tail-2/F-vs-missing new file mode 100755 index 000000000..8c1d01898 --- /dev/null +++ b/tests/tail-2/F-vs-missing @@ -0,0 +1,49 @@ +#!/bin/sh +# demonstrate that tail -F works for currently missing dirs +# Before coreutils-8.6, tail -F missing/file would not +# notice any subsequent availability of the missing/file. + +# Copyright (C) 2010 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 <http://www.gnu.org/licenses/>. + +. "${srcdir=.}/init.sh"; path_prepend_ ../src +test "$VERBOSE" = yes && tail --version + +debug='---disable-inotify' +debug= +tail $debug -F -s.1 missing/file > out 2>&1 & pid=$! + +check_tail_output() +{ + local delay="$1" + grep "$tail_re" out > /dev/null || + { sleep $delay; return 1; } +} + +# Wait up to 6.3s for tail to start with diagnostic: +# tail: cannot open `missing/file' for reading: No such file or directory +tail_re='cannot open' retry_delay_ check_tail_output .1 7 || fail=1 + +mkdir missing || fail=1 +(cd missing && echo x > file) + +# Wait up to 6.3s for this to appear in the output: +# "tail: `...' has appeared; following end of new file" +tail_re='has appeared' retry_delay_ check_tail_output .1 7 || + { echo "$0: file: unexpected delay?"; cat out; fail=1; } + +kill -HUP $pid + +Exit $fail diff --git a/tests/tail-2/F-vs-rename b/tests/tail-2/F-vs-rename index 74db80137..98b36e745 100755 --- a/tests/tail-2/F-vs-rename +++ b/tests/tail-2/F-vs-rename @@ -18,39 +18,36 @@ # You should have received a copy of the GNU General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. -if test "$VERBOSE" = yes; then - set -x - tail --version -fi - -. $srcdir/test-lib.sh +. "${srcdir=.}/init.sh"; path_prepend_ ../src +test "$VERBOSE" = yes && tail --version touch a b || framework_failure -debug='---disable-inotify -s .01' +debug='---disable-inotify' debug= -tail $debug -F a b > out 2>&1 & pid=$! +tail $debug -F -s.1 a b > out 2>&1 & pid=$! + +check_tail_output() +{ + local delay="$1" + grep "$tail_re" out > /dev/null || + { sleep $delay; return 1; } +} -# Wait until tail has started... +# Wait up to 6.3s for tail to start echo x > a -until grep '^x$' out >/dev/null 2>&1; do :; done +tail_re='^x$' retry_delay_ check_tail_output .1 7 || fail=1 mv a b || fail=1 -# Wait for the diagnostic: +# Wait 6.3s for this diagnostic: # tail: `a' has become inaccessible: No such file or directory -until grep inaccessible out >/dev/null 2>&1; do :; done +tail_re='inaccessible' retry_delay_ check_tail_output .1 7 || fail=1 echo x > a # Wait up to 6.3s for this to appear in the output: # "tail: `...' has appeared; following end of new file" -tail_f_vs_rename_1() -{ - local delay="$1" - grep 'has appeared;' out > /dev/null || - { sleep $delay; return 1; } -} -retry_delay_ tail_f_vs_rename_1 .1 7 || +tail_re='has appeared' retry_delay_ check_tail_output .1 7 || { echo "$0: a: unexpected delay?"; cat out; fail=1; } echo y >> b diff --git a/tests/tail-2/inotify-hash-abuse b/tests/tail-2/inotify-hash-abuse index 65a341211..d45668a69 100755 --- a/tests/tail-2/inotify-hash-abuse +++ b/tests/tail-2/inotify-hash-abuse @@ -16,30 +16,33 @@ # You should have received a copy of the GNU General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. -if test "$VERBOSE" = yes; then - set -x - tail --version -fi - -. $srcdir/test-lib.sh +. "${srcdir=.}/init.sh"; path_prepend_ ../src +test "$VERBOSE" = yes && tail --version # 9 is a magic number, related to internal details of tail.c and hash.c n=9 seq $n | xargs touch || framework_failure -debug='---disable-inotify -s .01' +debug='---disable-inotify' debug= -tail $debug -qF $(seq $n) > out 2>&1 & pid=$! +tail $debug -s.1 -qF $(seq $n) > out 2>&1 & pid=$! + +check_tail_output() +{ + local delay="$1" + grep "$tail_re" out > /dev/null || + { sleep $delay; return 1; } +} -# Wait until tail has started... +# Wait up to 6.3s for tail to start echo x > $n -until grep '^x$' out >/dev/null 2>&1; do :; done +tail_re='^x$' retry_delay_ check_tail_output .1 7 || fail=1 mv 1 f || fail=1 -# Wait for this diagnostic: +# Wait 6.3s for this diagnostic: # tail: `1' has become inaccessible: No such file or directory -until grep inaccessible out >/dev/null 2>&1; do :; done +tail_re='inaccessible' retry_delay_ check_tail_output .1 7 || fail=1 # Trigger the bug. Before the fix, this would provoke the abort. echo a > 1 || fail=1 diff --git a/tests/tail-2/wait b/tests/tail-2/wait index 332cfcc09..a9636910e 100755 --- a/tests/tail-2/wait +++ b/tests/tail-2/wait @@ -53,7 +53,7 @@ for inotify in ---disable-inotify ''; do timeout 1 tail -s0.1 -F $inotify not_here test $? = 124 || fail=1 - grep -v 'tail: inotify cannot be used, reverting to polling:' tail.err > x + grep -Ev 'inotify (resources exhausted|cannot be used)' tail.err > x mv x tail.err test -s tail.err && fail=1 :>tail.err |