summaryrefslogtreecommitdiff
path: root/src/tail.c
AgeCommit message (Collapse)Author
2011-06-01tail: fix an inconsequential bug spotted by coverityJim Meyering
* src/tail.c (start_bytes): Increase *READ_POS (not READ_POS) by the number of bytes read. This is a real bug that happens to have no consequence in practice. First, this code is exercised only when tailing-forever a non-regular file by bytes, and with a start-relative offset, e.g., "mkfifo f; tail -f -c +3 f", but even then, the invalid READ_POS value does not influence how tail works. It is stored in the File_spec.size member, but that member is not used at all in tail_forever_inotify, and in tail_forever, it is used only when the File_spec refers to a regular file.
2011-05-11maint: tail: mark a global variable as staticJim Meyering
* src/tail.c [HAVE_INOTIFY] (inotify_wd_mask): Declare static.
2011-04-25tail --follow=name no longer implies --retryJim Meyering
* src/tail.c (tail_forever_inotify): Just as without inotify, tail --follow=name now terminates when the last tailed-by-name file is unlinked or moved aside. This bug was introduced on 2009-06-15 via commit ae494d4b, "tail: use inotify if it is available". Reported by Tim Underwood in http://thread.gmane.org/gmane.comp.gnu.coreutils.bugs/22286 * NEWS (Bug fixes): Mention this. * tests/tail-2/follow-name: Test for this. * tests/Makefile.am (TESTS): Add it.
2011-04-25doc: tail/inotify does use --sleep-interval=S, with --pid=PJim Meyering
* doc/coreutils.texi (tail invocation): Mention it. * src/tail.c (usage): Likewise. (tail_forever_inotify): Clarify comment.
2011-01-24tail: avoid new diagnostic when applying -f to a pipe on linux-2.3.38Jim Meyering
* src/tail.c (fremote): Do not print a diagnostic when fstatfs (pipe_FD, &buf) fails, as it now does on linux-2.3.38. This avoids the spurious failure of tests/misc/tail's f-pipe-1 test, when running in input-from-pipe mode.
2011-01-01maint: update all copyright year number rangesJim Meyering
Run "make update-copyright".
2010-12-28coreutils: keep lines within 80-column limitsPaul Eggert
* cfg.mk (LINE_LEN_MAX, FILTER_LONG_LINES): New macros. (sc_long_lines): New rule. * HACKING: Use shorter URLs to the same material. * doc/Makefile.am, doc/coreutils.texi, m4/boottime.m4: * man/help2man, man/stdbuf.x, src/Makefile.am, src/cat.c, src/copy.c: * src/cp.c, src/dd.c, src/df.c, src/du.c, src/groups.c, src/install.c: * src/ls.c, src/md5sum.c, src/mv.c, src/od.c, src/pinky.c, src/ptx.c: * src/readlink.c, src/remove.c, src/rmdir.c, src/setuidgid.c: * src/sort.c, src/tail.c, src/touch.c, tests/Coreutils.pm: * tests/cp/existing-perm-race, tests/cp/perm, tests/cp/preserve-gid: * tests/du/2g, tests/du/long-from-unreadable, tests/init.sh: * tests/install/basic-1, tests/ls/nameless-uid: * tests/ls/readdir-mountpoint-inode, tests/misc/chroot-credentials: * tests/misc/cut, tests/misc/date, tests/misc/join, tests/misc/md5sum: * tests/misc/sha1sum, tests/misc/sha224sum, tests/misc/sort: * tests/misc/sort-continue, tests/misc/sort-files0-from: * tests/misc/sort-rand, tests/misc/stdbuf, tests/misc/tr: * tests/misc/uniq, tests/mv/atomic, tests/mv/part-fail: * tests/mv/part-symlink, tests/mv/sticky-to-xpart, tests/pr/pr-tests: * tests/rm/fail-2eperm, tests/rm/interactive-always: Reformat to fit within 80 columns. * doc/Makefile.am (BAD_POSIX_PERL): New macro. * doc/coreutils.texi: Reword slightly, to make menus and index lines shorter. * src/md5sum.c: Redo --help output so that it fits within 79 columns, since that's a bit more portable and all the other --help strings fit in 79 columns.
2010-12-14doc: tail: semi-deprecate --sleep-interval and --max-unchanged-statsJim Meyering
Those options are useful only on systems that lack inotify support and in the unusual event that a system with inotify support must resort to polling. * src/tail.c (usage): Note that the --max-unchanged-stats=N and --sleep-interval=N options are rarely useful on systems with inotify support. * doc/coreutils.texi (tail invocation): Likewise.
2010-10-25tail: support rechecking currently missing remote dirsPádraig Brady
src/tail.c (main): As an optimization, don't bother checking for stdin or remote files, when ---disable-inotify is specified. To improve the fix in commit 61b77891, set the disable_inotify flag when we fall back to polling, so that we recheck remote files. NEWS: Mention the fix
2010-10-12tail: fix checking of currently unavailable directoriesPádraig Brady
* src/tail.c (tail_forever_inotify): Handle the case where tail --follow=name with inotify, is not able to add a watch on a specified directory. This may happen due to inotify resource limits or if the directory is currently missing or inaccessible. In all these cases, revert to polling which will try to reopen the file later. Note inotify returns ENOSPC when it runs out of resources, and instead we report a particular error message, lest users think one of their file systems is full. (main): Document another caveat with using inotify, where we currently don't recheck directories recreated after the initial watch is setup. * tests/tail-2/F-vs-rename: Fix the endless loop triggered by the above issue. * tests/tail-2/inotify-hash-abuse: Likewise. * tests/tail-2/wait: Don't fail in the resource exhaustion case. * tests/tail-2/F-vs-missing: A new test for this failure mode which was until now just triggered on older buggy linux kernels which returned ENOSPC constantly from inotify_add_watch(). * NEWS: Mention the fix.
2010-06-08maint: adjust INT_BUFSIZE_BOUND usage for maintainabilityJim Meyering
* src/tail.c (xlseek): Give INT_BUFSIZE_BOUND a variable name, not a type name. * src/ls.c (gobble_file, format_user_or_group_width): Likewise. * src/head.c (elide_tail_bytes_pipe): Likewise. (elide_tail_lines_seekable, main): Likewise. [This change is not complete -- there are doubtless other uses that can be updated in the same way.]
2010-04-04tail: include sys/vfs.h (if possible) when sys/statfs.h is absentMarc Kleine-Budde
* src/tail.c [HAVE_INOTIFY && !HAVE_SYS_STATFS_H]: Include <sys/vfs.h>.
2010-01-01maint: update all FSF copyright year lists to include 2010Jim Meyering
Use this command: git ls-files | grep -v COPYING \ | xargs env UPDATE_COPYRIGHT_USE_INTERVALS=1 \ build-aux/update-copyright
2009-12-31doc: update tail's documentation to allow for new -F semanticsJim Meyering
* src/tail.c (usage): Reword tail -F description, so that it no longer mentions details specific to the non-inotify implementation. Also, join diagnostic strings (while staying under the 509-byte limit) to ease formatting of translations. The latter was prompted by a report from Stéphane Raimbault. * doc/coreutils.texi (tail invocation): Update description here, too.
2009-12-30tail -F: don't stop following the target of a renameGiuseppe Scrivano
This fixes a bug whereby tail -F would fail to track changes to a file that was a target of a rename, and when the source of the rename was another tailed file. * src/tail.c (tail_forever_inotify): Ensure the wd is not already present in the hash table before trying to add it. When a new watch descriptor is added to the `wd_to_name' hash table, check that it is not already present. If it is present then remove the previous element.
2009-12-29tail: remove `fdspec' from the hash table before changing its keyGiuseppe Scrivano
* src/tail.c (tail_forever_inotify): Avoid modifying fdspec->wd while it is in the wd_to_name hash table. Once it is removed, it can be added using the new `wd' as key for the hash table. This fixes the abort-inducing bug reported by Rob Wortman in http://thread.gmane.org/gmane.comp.gnu.coreutils.bugs/19372
2009-12-29tail: rename an internal variableJim Meyering
* src/tail.c (tail_forever_inotify): s/wd_table/wd_to_name/
2009-12-29tail: avoid read-beyond-end-of-buffer errorJim Meyering
* src/tail.c (tail_forever_inotify): Do not use f[i] in a context where i may be larger than the largest valid index. In the final "if" clause in which we'd remove an inotify watch, we might have used f[n_files]. Use fspec instead, since it is guaranteed to be defined.
2009-12-26tail: shrink internal struct by 8 bytesJim Meyering
* tail.c (struct File_spec): Rearrange struct members to decrease size by 8 bytes to 76,96 on i686,x86_64 respectively.
2009-12-25maint: tail: avoid in-function #if directivesJim Meyering
* src/tail.c (fremote): Add a comment. Move definition "up" to precede first use, so we can remove its prototype and the #if..#endif around each use. (any_remote_file): Rename from any_remote_files.
2009-12-25tail: fix --follow to not use inotify on remote filesPádraig Brady
* src/tail.c (struct File_spec): Add a flag to record if file is remote. (recheck): If we're using inotify then check if the file has gone remote and if so, drop it with a warning. (any_remote_files): A new function to check for any open remote files. (tailable_stdin): A new function to refactor the check for whether a tailable file was specified through stdin. (fremote): A new function to check if a file descriptor refers to a remote file. (tail_forever_inotify): Add some comments. (tail_file): Record if a file is remote when initially opened. (main): Disable inotify if any remote files specified. Also document the caveat about remounted files not being noticed by inotify. * NEWS: Mention the fix.
2009-12-11tail: don't call fstat on an uninitialized FDJim Meyering
This bug showed up via valgrind as a "Conditional jump or move depends on uninitialized value(s)" error. * src/tail.c (ignore_fifo_and_pipe): New function. (main): Use it only when tailing forever. The code to compute n_viable and mark some F[i] as ignored would call isapipe on an uninitialized file descriptor. But n_viable and those .ignored marks are useful/used only when tailing forever. This bug was introduced via commit f0ff8c73 (7.6), "tail: make the new piped-stdin test as portable as the old one". * NEWS (Bug fixes): Mention it.
2009-11-24build: fix link failure on cygwinEric Blake
Cygwin 1.5 has a broken sleep, and the gnulib tests dragged in rpl_sleep which then caused a link failure because it wasn't in libcoreutils.a. We could solve it by using the gnulib sleep module. However, sleep and usleep may interact poorly with SIGALRM, and they have less granularity; so it is better to adopt a policy that if we must sleep, prefer xnanosleep. * src/sort.c (pipe_fork): Use xnanosleep, to avoid the need for rpl_sleep on cygwin, and to reduce granularity. (MAX_FORK_TRIES_COMPRESS, MAX_FORK_TRIES_DECOMPRESS): Increase, to account for reduction in granularity. * src/tail.c (tail_file): Use xnanosleep in debug code. * cfg.mk (sc_prohibit_sleep): New rule.
2009-11-16tail -F can fail to track a file after it's been rotatedJim Meyering
Tailing forever and by-name (--follow=name, -F), tail would sometimes fail to follow a file that had been removed via rename. If you can't apply this patch and have tail 7.6 or newer, you can work around the bug via the undocumented --disable-inotify option. * src/tail.c (tail_forever_inotify): When tailing by name (-F), do not un-watch a file upon receipt of the IN_MOVE_SELF event. Reported by Arjan Opmeer in http://bugs.debian.org/548439. * NEWS (Bug fixes): Mention it. Also see http://marc.info/?l=coreutils-bug&m=125829031916515 * tests/Makefile.am (TESTS): Add tail-2/inotify-rotate. * tests/tail-2/inotify-rotate: New test.
2009-10-22tail -f: avoid a race conditionGiuseppe Scrivano
* NEWS (Bug fixes): Mention it. * src/tail.c (check_fspec): New function. (tail_forever_inotify): Ensure there is no new data before entering the inotify events wait loop.
2009-10-13tail: add add missing backslash at the end of a line in usageC de-Avillez
* src/tail.c (usage): Add missing backslash at the end of a line.
2009-10-12tail: tweak usage for more clarityEric Blake
* src/tail.c (usage): Spell out -n +K. * THANKS: Update. Reported by Jan-Pawel Wrozstinski.
2009-10-02tail: avoid a race where we could miss new data with --pidPádraig Brady
* src/tail.c (tail_forever, tail_forever_inotify): Close a race in tail_forever_inotify where new data written after the file check by a now dead process, but before the pid check, is not output. We use the POSIX guarantee that read() and write() are serialized wrt each other even in separate processes, to assume full file consistency after exit() and so poll for new data _after_ the writer has exited. This also allows us to not redundantly _wait_ for new data if the process is dead. * tests/tail-2/pid: Remove the now partially invalid sub second sleep check as we now don't unconditionally wait, and replace it with a check for the redundant sleep. Also clarify some of the existing comments. * NEWS: Mention the fix.
2009-09-23maint: Use logical rather than bitwise operators on boolsPádraig Brady
This is because bitwise operators are: - confusing and inconsistent in a boolean context - non short circuiting - brittle in C89 where bool can be an int (so > 1)
2009-09-21doc: mention the texinfo documentation in --helpPádraig Brady
* src/system.h: Rename emit_bug_reporting_address() to emit_ancillary_info() and update it to not print the translation project address in en_* locales, and _do_ print it in the 'C' (and other) locales so that it's included in the default man page. Also mention how to invoke the texinfo documentation for each command. Also move the "hard-locale.h" include to the 8 files that now use it. * man/help2man: Strip the newly added texinfo reference from the --help output as a more verbose version is already added by help2man. Suggestion from C de-Avillez
2009-09-08tail: make the new piped-stdin test as portable as the old oneJim Meyering
* src/tail.c (main): Adapt piped-stdin test to use the same isapipe, test as was used in the preceding POSIXLY_CORRECT condition. Remove the now-subsumed POSIXLY_CORRECT test. Reported by Pádraig Brady. * doc/coreutils.texi (tail invocation): Document this change. * NEWS (Changes in behavior): Reclassify, clarify.
2009-09-07tail: syntax-only: use "false", rather than equivalent, 0Jim Meyering
* src/tail.c (record_open_fd): Initialize "->ignore" to false, not 0.
2009-09-07tail: ignore -f for piped-stdin, as POSIX requiresJim Meyering
* src/tail.c (main): Tailing a pipe "forever" is not useful, and POSIX specifies that tail ignore the -f when there is no file argument and stdin is a FIFO or pipe. So we do that. In addition, GNU tail excludes "-" arguments from the list of files to tail forever, when the associated file descriptor is connected to a FIFO or pipe. Before this change, ":|tail -f" would hang. Reported by Ren Yang and Ulrich Drepper. * tests/tail-2/pipe-f: Test for this. * tests/tail-2/pipe-f2: Ensure tail doesn't exit early for a fifo. * tests/Makefile.am (TESTS): Add these tests. * NEWS (POSIX conformance): Mention it.
2009-09-07tail: don't give up on inotify mode for an already-ignored "-"Jim Meyering
* src/tail.c (main): Adjust today's change to honor the F[i].ignore flag that may have been set in tail_file.
2009-09-07tail -f: handle "-"/stdin once againJim Meyering
* src/tail.c (main) [HAVE_INOTIFY]: When stdin (i.e., "-", or no args, but not /dev/stdin) is specified on the command line, don't use inotify. Reported by Bill Brelsford in <http://bugs.debian.org/545422>. * tests/tail-2/follow-stdin: New file. Test for this. * tests/Makefile.am (TESTS): Add the test. * NEWS (Bug fixes): Mention it. This bug was introduced in coreutils-7.5 via commit ae494d4b, 2009-06-02, "tail: use inotify if it is available".
2009-09-06tail: flush initial output before possibly blockingJim Meyering
* src/tail.c (main): Flush any output from tail_file, before calling tail_forever_inotify, which can block. * tests/tail-2/flush-initial: New file. Test for the bug. * tests/Makefile.am (TESTS): Add tail-2/flush-initial. * NEWS (Bug fixes): Mention it. This bug was introduced in coreutils-7.5 via commit ae494d4b, 2009-06-02, "tail: use inotify if it is available".
2009-09-05doc: make the tail --sleep-interval help less confusingPádraig Brady
* src/tail.c (usage): I read "approximately S seconds" as "approximately 5 seconds" for approximately 5 seconds.
2009-09-05tests: test old tail -f method even on systems with inotifyPádraig Brady
* src/tail.c (main): Add an undocumented ---disable-inotify option to allow disabling inotify. * tests/tail-2/pid: Run test in both normal and "disable_inotify" modes. * tests/tail-2/tail-n0f: Likewise. * tests/tail-2/wait: Likewise. * tests/tail-2/append-only: Likewise.
2009-09-01maint: tail: remove unnecessary initializationJim Meyering
* src/tail.c (tail_bytes): Don't compute "diff" twice.
2009-08-25global: convert indentation-TABs to spacesJim Meyering
Transformed via this shell code: t=$'\t' git ls-files \ | grep -vE '(^|/)((GNU)?[Mm]akefile|ChangeLog)|\.(am|mk)$' \ | grep -vE 'tests/pr/|help2man' \ | xargs grep -lE "^ *$t" \ | xargs perl -MText::Tabs -ni -le \ '$m=/^( *\t[ \t]*)(.*)/; print $m ? expand($1) . $2 : $_'
2009-08-13tail: fix tail -f failure when inotify usedPádraig Brady
* src/tail.c (tail_forever_inotify): Remove the redundant and incorrect error check of the return from inotify_add_watch(). Also initialize the wd member of each File_spec to an invalid value. Reported by C de-Avillez.
2009-07-30tail: tweak indentationJim Meyering
* src/tail.c (tail_forever_inotify): Adjust indentation of continued line.
2009-07-30tail: properly parse fractional seconds when monitoring a pidPádraig Brady
* src/tail.c (tail_forever_inotify): The fractional part of the delay was 1000 times too large. * tests/tail-2/pid: Add a test to ensure the timeout happens for this case.
2009-07-30tail: exit successfully upon watched process deathGiuseppe Scrivano
* src/tail.c (tail_forever_inotify): If a PID is specified and the watched process dies, exit with status EXIT_SUCCESS, rather than falling through to an EXIT_FAILURE.
2009-07-28tail: use the inotify backend also with --pid=PIDGiuseppe Scrivano
* src/tail.c (tail_forever_inotify): When a PID is specified, use select to block for no more than sleep_interval seconds at a time, and check for process death upon timeout. (main): Adapt to new tail_forever_inotify interface.
2009-07-11tail: adjust type of a local variableJim Meyering
* src/tail.c (tail_forever_inotify): Declare "len" to be of type size_t, not ssize_t, since the former is what safe_read returns.
2009-07-08tail: use size_t for counter and index variables, ...Jim Meyering
* src/tail.c (any_live_files): ... not "int" or even unsigned int (tail_forever, tail_forever_inotify, main): Likewise.
2009-07-08tail: declare "file descriptor" variable to be "int", not size_tJim Meyering
* src/tail.c (tail_forever_inotify): Use "int", not size_t as the type of a file descriptor variable.
2009-07-03tail: avoid an inotify portability problem in kernels prior to 2.6.21Giuseppe Scrivano
* src/tail.c (tail_forever_inotify): Handle the special case in which an old inotify watcher returns 0. Affects kernels in [2.6.13, 2.6.21).
2009-06-29tail: add comments noting potential inotify-related problemsJim Meyering
* src/tail.c (tail_forever_inotify): Add two FIXME comments.