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2013-11-27tail: improve inotify handling of symlinksPádraig Brady
Previous behavior failed to read contents of a (re)appearing file, when symlinked by tail's watched file. Also we now diagnose other edge cases when running in inotify mode, where an initially missing or regular file changes to a symlink. * src/tail.c (main): If any arg is a symlink, use polling mode. (recheck): Diagnose the edge case where a symlink appears during inotify processing. * tests/tail-2/symlink.sh: Test the fix. Mention the edge cases. * tests/local.mk: Reference the new test. * NEWS: Mention the fix. Reported by: Ondrej Oprala
2013-08-05doc: more semicolons instead of periods in option descriptionsBenno Schulenberg
Also slightly rephrase some descriptions for extra clarity, and add more consistent indentation. * src/df.c (usage): Semicolon, no final period. * src/du.c (usage): Likewise, plus indentation and clarifying words. * src/ls.c (usage): Semicolon, rephrasings, added parentheses for clarity, indentation. * src/rm.c (usage): Semicolons. * src/tail.c (usage): Adjust -f description to prefer explanatory language instead of option syntax.
2013-08-01doc: use semicolon instead of period in option descriptionsBenno Schulenberg
Also do not end option descriptions with a period, properly indent continuation lines, and make some tiny clarifications. * src/du.c (usage): Lowercase after semicolon. * src/ls.c (usage): Semicolons instead of periods, small rephrasing and two hyphens for clarity, proper indentation. * src/mktemp.c (usage): Semicolons and lowercase. * src/od.c (usage): Semicolons. * src/ptx.c (usage): Use the standard phrase, clarify default option. * src/setuidgid.c (usage): Properly indent continuation line. * src/split.c (usage): Semicolons, lowercase, no final period. * src/stat.c (usage): Semicolons, lowercase. * src/tail.c (usage): Proper indentation, one shorter rephrasing, semicolons, no final periods. * src/timeout.c (usage): Properly indent, semicolons, no final periods. Fixes http://bugs.gnu.org/14976
2013-05-18maint: port --enable-gcc-warnings to clangPaul Eggert
* configure.ac: If clang, add -Wno-format-extra-args and -Wno-tautological-constant-out-of-range-compare. * gl/lib/rand-isaac.c (ind): * gl/lib/randread.c (readisaac): * src/ls.c (dev_ino_push, dev_ino_pop): * src/sort.c (buffer_linelim): * src/system.h (is_nul): * src/tail.c (tail_forever_inotify): Rewrite to avoid casts that clang dislikes. It's good to avoid casts anyway. * src/expr.c (integer_overflow): Declare only if it exists. (die): Remove; unused. * src/ls.c (dev_ino_push): New function, replacing ... (DEV_INO_PUSH): ... this removed macro. All uses changed. (decode_switches): Rewrite "str"+i to &str[i].
2013-04-20tail: exit following by descriptor when no tailable file leftBernhard Voelker
As a side effect of the previous commit which fixes 'tail -f --retry' to wait for a file to appear, tail would not exit when the last file appears untailable and gives up on this file. This can happen, for example, when the argument file name appears as directory. Tail sets the 'ignore' flag of this file to true, but instead of exiting the program, tail would continue the loop. * src/tail.c (any_live_files): Change the function to return true if any of the files is still tailable or if tail should continue to try to check again. (tail_forever): Change the condition to break the loop in the "no files remaining" case, because now any_live_files() will care about it, as mentioned above. (parse_options): When --retry is used without any follow mode, then reset reopen_inaccessible_files to false. * tests/tail-2/retry.sh: Add test case.
2013-04-20tail: let -f --retry wait for inaccessible filesBernhard Voelker
The --retry option is indeed useful for both following modes by name and by file descriptor. The difference is that in the latter case, it is effective only during the initial open. As a regression of the implementation of the inotify support, tail -f --retry would immediately exit if the given file is inaccessible. * src/tail.c (usage): Change the description of the --retry option: remove the note that this option would mainly be useful when following by name. (main): Change diagnosing dubios uses of --retry option: when the --retry option is used without following, then issue a warning that this option is ignored; when it is used together with --follow=descriptor, then issue a warning that it is only effective for the initial open. Disable inotify also in the case when the initial open in tail_file() failed (which is the actual bug fix). * init.cfg (retry_delay_): Pass excess arguments to the test function. * tests/tail-2/retry.sh: Add new tests. * tests/local.mk (all_tests): Mention it. * doc/coreutils.texi (tail invocation): Enhance the documentation of the --retry option. Clarify the difference in tail's behavior regarding the --retry option when combined with the following modes name versus descriptor. * NEWS (Bug fixes): Mention the fix. Reported by Noel Morrison in: http://lists.gnu.org/archive/html/coreutils/2013-04/msg00003.html
2013-04-04tail: exit without reading input if would never outputPádraig Brady
* src/tail.c (main): If -n0 or -c0 were specified without -f, then no data would ever be output, so exit without reading input. * tests/tail-2/tail-n0f.sh: Augment the related test with this case.
2013-01-23maint: define usage note about mandatory args centrallyBernhard Voelker
Each program with at least one long option which is marked as 'required_argument' and which has also a short option for that option, should print a note about mandatory arguments. Define that well-known note centrally and use it rather than literal printf/fputs, and add it where it was missing. * src/system.h (emit_mandatory_arg_note): Add new function. * src/cp.c (usage): Use it rather than literal printf/fputs. * src/csplit.c, src/cut.c, src/date.c, src/df.c, src/du.c: * src/expand.c, src/fmt.c, src/fold.c, src/head.c, src/install.c: * src/kill.c, src/ln.c, src/ls.c, src/mkdir.c, src/mkfifo.c: * src/mknod.c, src/mv.c, src/nl.c, src/od.c, src/paste.c: * src/pr.c, src/ptx.c, src/shred.c, src/shuf.c, src/sort.c: * src/split.c, src/stdbuf.c, src/tac.c, src/tail.c, src/timeout.c: * src/touch.c, src/truncate.c, src/unexpand.c, src/uniq.c: Likewise. * src/base64.c (usage): Add call of the above new function because at least one long option has a required argument. * src/basename.c, src/chcon.c, src/date.c, src/env.c: * src/nice.c, src/runcon.c, src/seq.c, src/stat.c, src/stty.c: Likewise.
2013-01-01maint: update all copyright year number rangesJim Meyering
Run "make update-copyright", but then also run this, perl -pi -e 's/2\d\d\d-//' tests/sample-test to make that one script use the single most recent year number.
2012-08-03tail: avoid rare error-path FD leakJim Meyering
* src/tail.c (tail_forever): Close FD to avoid leak after a failed fstat.
2012-07-25tail: avoid misleading diagnostic upon fstat failureJim Meyering
* src/tail.c (check_fspec): Save fstat-induced errno *before* calling close_fd, not after. Otherwise, the close could well clobber the global errno, making tail print an invalid diagnostic. This could happen only with tail -f, and even then, only when a valid file descriptor were to provoke fstat failure.
2012-01-27maint: use single copyright year rangeJim Meyering
Run "make update-copyright".
2012-01-09maint: src/*.[ch]: convert more `...' to '...'Jim Meyering
Run this (twice): git grep -E -l '`.+'\' src/*.[ch] \ |xargs perl -pi -e 's/`(.+?'\'')/'\''$1/'
2012-01-09maint: src/*.c: change remaining quotes (without embedded spaces)Jim Meyering
Run this (twice): git grep -E -l '`[^ ]+'\' src/*.c \ |xargs perl -pi -e 's/`([^ ]+'\'')/'\''$1/'
2012-01-09maint: convert `...' to '...' in --help outputJim Meyering
All affected lines end with \ or \n\, so run this command until it produces no new changes (4 times): git grep -E -l '`[^ ]+'\''.*\\' src \ |xargs perl -pi -e 's/`([^ ]+'\''.*\\)/'\''$1/'
2012-01-07maint: use new emit_try_help in place of equivalent fprintfJim Meyering
Run this command: perl -0777 -pi -e \ 's/fprintf \(stderr, _\("Try `%s --help.*\n.*;/emit_try_help ();/m'\ src/*.c
2012-01-02build: tail: avoid type/format mismatch warning from gccJim Meyering
Without this change, gcc's -Werror=format would complain that the '%lx' format requires 'long unsigned int', not 'int'. * src/tail.c (fremote): Use a temporary variable.
2012-01-01maint: update all copyright year number rangesJim Meyering
Run "make update-copyright".
2011-12-28tail: avoid theoretically undefined behaviorJim Meyering
* src/tail.c (start_lines): Do not form potentially-invalid address. Use safe_read's return value as a pointer offset only after ensuring that it is not SAFE_READ_ERROR (size_t)(-1). Spotted by coverity. Also, move declaration of "p" to be closer to first use.
2011-12-23tail: with -f, use polling when a file is on an FS of unknown typeJim Meyering
Before, we would use inotify in that case, which would work as long as updates were taking place locally, but not at all when remote. Move hard-coded list of known remote FS types into a more maintainable table in stat.c, alongside the list of FS names and magic numbers. Generate a new is_local_fs_type function. * src/Makefile.am (fs-is-local.h): New rule, generated file. * src/extract-magic: Revamp to parse local/remote keyword after each magic number in src/stat.c's case statements. Accept new --local option. * src/.gitignore: Ignore the generated fs-is-local.h. * src/tail.c [HAVE_INOTIFY]: Include fs-is-local.h. (fremote) [HAVE_INOTIFY]: Use the new function in place of the switch stmt with hard-coded list of FS types. Emit a warning when processing a file on a file system of unknown type. * NEWS (Changes in behavior): Mention it. Suggested by Sven Breuner.
2011-12-22tail,stat: add support for FhGFSJim Meyering
* src/stat.c (human_fstype): Add a case: fhgfs, 0x19830326. * src/tail.c (fremote): Add S_MAGIC_FHGFS. * NEWS (Bug fixes): Update the entry for GPFS to mention FhGFS, too. Reported by Sven Breuner.
2011-10-21tail: with -f, use nanosleep (not inotify) on a GPFS file systemMartial Bornet
Because tail's fremote function did not designate GPFS as a remote file system type, tail -f would mistakenly attempt to use inotify, which cannot work with a remote file system. * src/tail.c (fremote): List GPFS as a remote file system type. * NEWS (Bug fixes): Mention it. Reported in http://bugs.debian.org/646022.
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.