Commit Graph
73 Commits
Author SHA1 Message Date
Yu Watanabe 68a2ed61eb log: introduce log_trace_errno() 2022-01-28 10:50:36 +09:00
Zbigniew Jędrzejewski-Szmek a7d15a2465 nss: only read logging config from environment variables
log_parse_environment() uses should_parse_proc_cmdline() to determine whether
it should parse settings from the kernel command line. But the checks that
should_parse_proc_cmdline() apply to the whole process, and we could get a positive
answer also when log_parse_environment() was called from one of the nss modules.
In case of nss-modules, we don't want to look at the kernel command line.

log_parse_environment_variables() that only looks at the environment variables
is split out and used in the nss modules.

Fixes #22020.
2022-01-11 13:39:52 +01:00
Zbigniew Jędrzejewski-Szmek 5f74fcd41c basic/log: allow errno values higher than 255
When the support for "synthetic errno" was added, we started truncating
the errno value to just the least significant byte. This is generally OK,
because errno values are defined up to ~130.

The docs don't really say what the maximum value is. But at least in principle
higher values could be added in the future. So let's stop truncating
the values needlessly.

The kernel (or libbpf?) have an error where they return 524 as an errno
value (https://bugzilla.redhat.com/show_bug.cgi?id=2036145). We would
confusingly truncate this to 12 (ENOMEM). It seems much nicer to let
strerror() give us "Unknown error 524" rather than to print the bogus
message about ENOMEM.
2022-01-03 22:46:32 +00:00
Daan De Meyer 9c41618008 journal: Don't discard kmsg messages coming from journald itself
Previously, we discarded any kmsg messages coming from journald
itself to avoid infinite loops where potentially the processing
of a kmsg message causes journald to log one or more messages to
kmsg which then get read again by the kmsg handler, ...

However, if we completely disable logging whenever we're processing
a kmsg message coming from journald itself, we also prevent any
infinite loops as we can be sure that journald won't accidentally
generate logging messages while processing a kmsg log message.

This change allows us to store all journald logs generated during
the processing of log messages from other services in the system
journal. Previously these could only be found in kmsg which has
low retention, can't be queried using journalctl and whose logs
don't survive reboots.
2021-11-18 19:37:17 +00:00
Maanya Goenka 3cc3dc7736 systemd-analyze: option to exit with an error when 'verify' fails
The commit introduces a callback invoked from log_syntax_internal.
Use it from systemd-analyze to gather a list of units that contain
syntax warnings. A new command line option is added to make use of this.

The new option --recursive-errors takes in three possible modes:

1. yes - which is the default. systemd-analyze exits with an error when syntax warnings arise during verification of the
	 specified units or any of their dependencies.
3. no - systemd-analyze exits with an error when syntax warnings arise during verification of only the selected unit.
	Analyzing and loading any dependencies will be skipped.
4. one - systemd-analyze exits with an error when syntax warnings arise during verification
	 of only the selected units and their direct dependencies.

Below are two service unit files that I created for the purposes of testing:

1. First, we run the commands on a unit that does not have dependencies but has a non-existing key-value setting (i.e. foo = bar).

> cat <<EOF>testcase.service

[Unit]
foo = bar

[Service]
ExecStart = echo hello
EOF

OUTPUT:

maanya-goenka@debian:~/systemd (log-error)$ sudo build/systemd-analyze verify testcase.service
/home/maanya-goenka/systemd/testcase.service:2: Unknown key name 'foo' in section 'Unit', ignoring.
/usr/lib/systemd/system/plymouth-start.service:15: Unit configured to use KillMode=none. This is unsafe, as it disables systemd's process lifecycle management for the service. Please update your service to use a safer KillMode=, such as 'mixed' or 'control-group'. Support for KillMode=none is deprecated and will eventually be removed.
/usr/lib/systemd/system/dbus.socket:5: ListenStream= references a path below legacy directory /var/run/, updating /var/run/dbus/system_bus_socket → /run/dbus/system_bus_socket; please update the unit file accordingly.
/usr/lib/systemd/system/gdm.service:30: Standard output type syslog is obsolete, automatically updating to journal. Please update your unit file, and consider removing the setting altogether.
maanya-goenka@debian:~/systemd (log-error)$ echo $?
1

maanya-goenka@debian:~/systemd (log-error)$ sudo build/systemd-analyze verify --recursive-errors=yes testcase.service
/home/maanya-goenka/systemd/testcase.service:2: Unknown key name 'foo' in section 'Unit', ignoring.
/usr/lib/systemd/system/plymouth-start.service:15: Unit configured to use KillMode=none. This is unsafe, as it disables systemd's process lifecycle management for the service. Please update your service to use a safer KillMode=, such as 'mixed' or 'control-group'. Support for KillMode=none is deprecated and will eventually be removed.
/usr/lib/systemd/system/dbus.socket:5: ListenStream= references a path below legacy directory /var/run/, updating /var/run/dbus/system_bus_socket → /run/dbus/system_bus_socket; please update the unit file accordingly.
/usr/lib/systemd/system/gdm.service:30: Standard output type syslog is obsolete, automatically updating to journal. Please update your unit file, and consider removing the setting altogether.
maanya-goenka@debian:~/systemd (log-error)$ echo $?
1

maanya-goenka@debian:~/systemd (log-error)$ sudo build/systemd-analyze verify --recursive-errors=no testcase.service
/home/maanya-goenka/systemd/testcase.service:2: Unknown key name 'foo' in section 'Unit', ignoring.
maanya-goenka@debian:~/systemd (log-error)$ echo $?
1

maanya-goenka@debian:~/systemd (log-error)$ sudo build/systemd-analyze verify --recursive-errors=one testcase.service
/home/maanya-goenka/systemd/testcase.service:2: Unknown key name 'foo' in section 'Unit', ignoring.
/usr/lib/systemd/system/plymouth-start.service:15: Unit configured to use KillMode=none. This is unsafe, as it disables systemd's process lifecycle management for the service. Please update your service to use a safer KillMode=, such as 'mixed' or 'control-group'. Support for KillMode=none is deprecated and will eventually be removed.
/usr/lib/systemd/system/dbus.socket:5: ListenStream= references a path below legacy directory /var/run/, updating /var/run/dbus/system_bus_socket → /run/dbus/system_bus_socket; please update the unit file accordingly.
/usr/lib/systemd/system/gdm.service:30: Standard output type syslog is obsolete, automatically updating to journal. Please update your unit file, and consider removing the setting altogether.
maanya-goenka@debian:~/systemd (log-error)$ echo $?
1

2. Next, we run the commands on a unit that is syntactically valid but has a non-existing dependency (i.e. foo2.service)

> cat <<EOF>foobar.service

[Unit]
Requires = foo2.service

[Service]
ExecStart = echo hello
EOF

OUTPUT:

maanya-goenka@debian:~/systemd (log-error)$ sudo build/systemd-analyze verify foobar.service
/usr/lib/systemd/system/plymouth-start.service:15: Unit configured to use KillMode=none. This is unsafe, as it disables systemd's process lifecycle management for the service. Please update your service to use a safer KillMode=, such as 'mixed' or 'control-group'. Support for KillMode=none is deprecated and will eventually be removed.
/usr/lib/systemd/system/dbus.socket:5: ListenStream= references a path below legacy directory /var/run/, updating /var/run/dbus/system_bus_socket → /run/dbus/system_bus_socket; please update the unit file accordingly.
/usr/lib/systemd/system/gdm.service:30: Standard output type syslog is obsolete, automatically updating to journal. Please update your unit file, and consider removing the setting altogether.
foobar.service: Failed to create foobar.service/start: Unit foo2.service not found.
maanya-goenka@debian:~/systemd (log-error)$ echo $?
1

maanya-goenka@debian:~/systemd (log-error)$ sudo build/systemd-analyze verify --recursive-errors=yes foobar.service
/usr/lib/systemd/system/plymouth-start.service:15: Unit configured to use KillMode=none. This is unsafe, as it disables systemd's process lifecycle management for the service. Please update your service to use a safer KillMode=, such as 'mixed' or 'control-group'. Support for KillMode=none is deprecated and will eventually be removed.
/usr/lib/systemd/system/dbus.socket:5: ListenStream= references a path below legacy directory /var/run/, updating /var/run/dbus/system_bus_socket → /run/dbus/system_bus_socket; please update the unit file accordingly.
/usr/lib/systemd/system/gdm.service:30: Standard output type syslog is obsolete, automatically updating to journal. Please update your unit file, and consider removing the setting altogether.
foobar.service: Failed to create foobar.service/start: Unit foo2.service not found.
maanya-goenka@debian:~/systemd (log-error)$ echo $?
1

maanya-goenka@debian:~/systemd (log-error)$ sudo build/systemd-analyze verify --recursive-errors=no foobar.service
maanya-goenka@debian:~/systemd (log-error)$ echo $?
0

maanya-goenka@debian:~/systemd (log-error)$ sudo build/systemd-analyze verify --recursive-errors=one foobar.service
/usr/lib/systemd/system/plymouth-start.service:15: Unit configured to use KillMode=none. This is unsafe, as it disables systemd's process lifecycle management for the service. Please update your service to use a safer KillMode=, such as 'mixed' or 'control-group'. Support for KillMode=none is deprecated and will eventually be removed.
/usr/lib/systemd/system/dbus.socket:5: ListenStream= references a path below legacy directory /var/run/, updating /var/run/dbus/system_bus_socket → /run/dbus/system_bus_socket; please update the unit file accordingly.
/usr/lib/systemd/system/gdm.service:30: Standard output type syslog is obsolete, automatically updating to journal. Please update your unit file, and consider removing the setting altogether.
foobar.service: Failed to create foobar.service/start: Unit foo2.service not found.
maanya-goenka@debian:~/systemd (log-error)$ echo $?
1
2021-08-12 07:22:15 -07:00
Zbigniew Jędrzejewski-Szmek 04499a70fb Drop the text argument from assert_not_reached()
In general we almost never hit those asserts in production code, so users see
them very rarely, if ever. But either way, we just need something that users
can pass to the developers.

We have quite a few of those asserts, and some have fairly nice messages, but
many are like "WTF?" or "???" or "unexpected something". The error that is
printed includes the file location, and function name. In almost all functions
there's at most one assert, so the function name alone is enough to identify
the failure for a developer. So we don't get much extra from the message, and
we might just as well drop them.

Dropping them makes our code a tiny bit smaller, and most importantly, improves
development experience by making it easy to insert such an assert in the code
without thinking how to phrase the argument.
2021-08-03 10:05:10 +02:00
Dan Streetman 264f0afe0d log: add log_once() and log_once_errno() macros
These macros will log a message at the specified level only the first time
they are called. On all later calls, if the specified level is debug, the
logs will be suppressed; otherwise the message will be logged at debug.
2021-05-20 15:39:15 -04:00
Zbigniew Jędrzejewski-Szmek 59e8042ecd basic/log: change error for unset errno to ESTRPIPE
EIO is used in other contexts, so change ot something otherwise unused.
ENOTRECOVERABLE was also suggested, but it's used in various other places
in the code.

https://github.com/systemd/systemd/pull/19317#discussion_r614887661
2021-04-19 08:46:19 +02:00
Zbigniew Jędrzejewski-Szmek 75029e150b Do not try to return 0 from log_debug()
As @yuwata correctly points out, this became broken when log_debug()
started returning -EIO. I wanted to preserve this pattern, but it turns
out it is not very widely used, and preserving it would make the whole
thing, already quite complicated, even more complex.

log_debug() is made like log_info() and friends, and returns void.
2021-04-14 17:45:11 +02:00
Zbigniew Jędrzejewski-Szmek a626cb15c0 basic/log: assert that 0 is not passed as errno, except in test code
Let's assert if we ever happen to pass 0 to one of the log functions.
With the preceding commit to return -EIO from log_*(), passing 0 wouldn't
affect the return value any more, but it is still most likely an error.
The unit test code is an exception: we fairly often pass the return value
to print it, before checking what it is. So let's assert that we're not
passing 0 in non-test code. As with the previous check for %m, this is only
done in developer mode. We are depending on external code setting
errno correctly for us, which might not always be true, and which we can't
test, so we shouldn't assert, but just handle this gracefully.

I did a bunch of greps to try to figure out if there are any places where
we're passing 0 on purpose, and couldn't find any.
The one place that failed in tests is adjusted.

About "zerook" in the name: I wanted the suffix to be unambiguous. It's a
single "word" because each of the words in log_full_errno is also meaningful,
and having one term use two words would be confusing.
2021-04-14 17:07:06 +02:00
Zbigniew Jędrzejewski-Szmek 63275a7032 basic/log: assert that %m is not used when error is not set
This is only done in developer mode. It is a pretty rare occurence that we
make this kind of mistake. And even if it happens, the result is just a misleading
error message. So let's only do the check in non-release builds.
2021-04-14 16:19:54 +02:00
Zbigniew Jędrzejewski-Szmek cbe97b9c92 basic/log: force log_*_errno() to return negative
This silences some warnigns where gcc thinks that some variables are
unitialized. One particular case:

../src/journal/journald-server.c: In function 'ache_space_refresh':
../src/journal/journald-server.c:136:28: error: 'vfs_avail' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  136 |         uint64_t vfs_used, vfs_avail, avail;
      |                            ^~~~~~~~~
../src/journal/journald-server.c:136:18: error: 'vfs_used' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  136 |         uint64_t vfs_used, vfs_avail, avail;
      |                  ^~~~~~~~
cc1: all warnings being treated as errors

which is caused by

   d = opendir(path);
   if (!d)
           return log_full_errno(errno == ENOENT ? LOG_DEBUG : LOG_ERR,
                                 errno, "Failed to open %s: %m", path);
   if (fstatvfs(dirfd(d), &ss) < 0)
           return log_error_errno(errno, "Failed to fstatvfs(%s): %m", path);

For some reason on aarch64 gcc thinks we might return non-negative here. In
principle errno must be set in both cases, but it's hard to say for certain.
So let's make sure that our code flow is correct, even if somebody forgot to
set the global variable somewhere.
2021-04-14 16:19:54 +02:00
Zbigniew Jędrzejewski-Szmek e355fb6fb1 basic/log: fix log_trace()
log_trace() was always on. It's supposed to be opt-in.
2021-03-26 13:08:24 +01:00
Zbigniew Jędrzejewski-Szmek 2d93c20e5f tree-wide: use -EINVAL for enum invalid values
As suggested in https://github.com/systemd/systemd/pull/11484#issuecomment-775288617.

This does not touch anything exposed in src/systemd. Changing the defines there
would be a compatibility break.

Note that tests are broken after this commit. They will be fixed in the next one.
2021-02-10 14:46:59 +01:00
Yu Watanabe d2acb93dc5 tree-wide: enable colorized logging for daemons when run in console
It may be useful when debugging daemons.
2021-02-01 01:13:44 +09:00
Yu Watanabe 74189020eb log: make tools also read the kernel command line when run as a service
This effectively reverts 41d1f469cf.

Before this, e.g., `networkctl reload` invoked by `systemctl reload systemd-networkd.service`
does not produce debugging logs even if systemd.log-level=debug is set. This fixes
the issue.
2021-02-01 01:13:44 +09:00
Yu Watanabe 9fdee66f2d log: drop unused LogRealm
Already no binary is built with LOG_REALM= argument.
Hence, we can safely drop LogRealm now.
2021-01-25 20:32:18 +09:00
Yu Watanabe 5df4f46f28 log: drop unused log_full_errno_realm() macro 2021-01-25 20:32:18 +09:00
Zbigniew Jędrzejewski-Szmek b3a7915805 basic/log: add debug-level log_oom() variant
This is useful for contexts where only debug-level messages are allowed.
2020-12-11 08:22:41 +01:00
Lennart Poettering 1c36b8bf53 log: add helper set sets log level in all realms
Prompted-by: #17903
2020-12-09 18:26:17 +01:00
Yu Watanabe db9ecf0501 license: LGPL-2.1+ -> LGPL-2.1-or-later 2020-11-09 13:23:58 +09:00
Lennart Poettering 27ffec0831 log: update comment
The logic was changed in bc694c06e6, let's
update the comment accordingly.
2020-09-30 16:06:55 +02:00
Lennart Poettering 9ee806d1a8 log: optionally display thread ID in log output to tty
This is very useful when playing around with threaded tests, but should
be useful in other cases too.
2020-09-29 15:51:53 +02:00
Zbigniew Jędrzejewski-Szmek 44f0dd628c basic/log: make log_{info,warning,...} return void
log_debug still returns 0. I think it is legitimate to use 'return log_debug()' to
return 0. It is different than the other functions, since we often want to supress
errors logged at debug level. This case is quite common in the codebase and
we could use 'return log_debug_errno()' to make the code more consise.

For all other variants, a separate return line is required.
Previous commit changes all the non-conforming instances, now we can make it mandatory.
2020-09-08 17:40:46 +02:00
Filipe Brandenburger 41d1f469cf log: introduce log_parse_environment_cli() and log_setup_cli()
Presently, CLI utilities such as systemctl will check whether they have a tty
attached or not to decide whether to parse /proc/cmdline or EFI variable
SystemdOptions looking for systemd.log_* entries.

But this check will be misleading if these tools are being launched by a
daemon, such as a monitoring daemon or automation service that runs in
background.

Make log handling of CLI tools uniform by never checking /proc/cmdline or EFI
variables to determine the logging level.

Furthermore, introduce a new log_setup_cli() shortcut to set up common options
used by most command-line utilities.
2020-06-24 16:49:26 +02:00
Lennart Poettering 01262d0d9e Merge pull request #13084 from ddstreet/log_time
log: add support for prefixing console log messages with current timestamp
2020-03-30 17:57:34 +02:00
Daan De Meyer f455f8633e Silence Wstring-plus-int warning when using clangd with GCC. 2020-03-21 22:30:59 +01:00
Dan Streetman c5673ed0de log: add support for prefixing console log messages with current timestamp 2020-02-10 07:01:30 -05:00
Zbigniew Jędrzejewski-Szmek ab1a1ba5dc Drop trailing slash from assert_cc() definition
We use assert_cc(...); almost everywhere. Let's always require that.

https://github.com/systemd/systemd/issues/12997#issuecomment-510103988
2019-07-17 12:57:20 +02:00
Zbigniew Jędrzejewski-Szmek 62c6bbbc09 tree-wide: use PROJECT_FILE instead of __FILE__
This replaces the internal uses of __FILE__ with the new macro.
2019-07-04 10:36:00 +02:00
Zbigniew Jędrzejewski-Szmek a0b15b4177 basic/log: add a define for path relative to source root
When using build/ directory inside of the source directory:
__FILE__: ../src/test/test-log.c
RELATIVE_SOURCE_PATH: ..
PROJECT_FILE: src/test/test-log.c

When using a build directory outside of the source directory:
__FILE__: ../../../home/zbyszek/src/systemd-work/src/test/test-log.c
RELATIVE_SOURCE_PATH: ../../../home/zbyszek/src/systemd-work
PROJECT_FILE: src/test/test-log.c
2019-07-04 10:27:19 +02:00
Yu Watanabe f6d6d53237 log: expose log_object_internalv() 2019-03-21 23:37:39 +09:00
Yu Watanabe ee96382fdb log: make log_syntax() assign correct errno and show valid error cause 2019-03-04 15:18:06 +09:00
Zbigniew Jędrzejewski-Szmek 5dc881a359 basic/log: add note about operator precendence 2018-11-22 10:56:43 +01:00
Zbigniew Jędrzejewski-Szmek baaa35ad70 coccinelle: make use of SYNTHETIC_ERRNO
Ideally, coccinelle would strip unnecessary braces too. But I do not see any
option in coccinelle for this, so instead, I edited the patch text using
search&replace to remove the braces. Unfortunately this is not fully automatic,
in particular it didn't deal well with if-else-if-else blocks and ifdefs, so
there is an increased likelikehood be some bugs in such spots.

I also removed part of the patch that coccinelle generated for udev, where we
returns -1 for failure. This should be fixed independently.
2018-11-22 10:54:38 +01:00
Zbigniew Jędrzejewski-Szmek 52d86690d6 basic/log: add concept of "synthethic errnos"
Synthetic errnos are processed like normal, and may be used in %m and become
the return value from log_*(), but they are not logged in the journal.
2018-11-22 10:45:08 +01:00
Lennart Poettering 6bf3c61c57 log: introduce new helper call log_setup_service()
Let's reduce the common boilerplate and have a single setup function
used by all service code to setup logging.
2018-11-20 11:18:22 +01:00
Lennart Poettering 0c69794138 tree-wide: remove Lennart's copyright lines
These lines are generally out-of-date, incomplete and unnecessary. With
SPDX and git repository much more accurate and fine grained information
about licensing and authorship is available, hence let's drop the
per-file copyright notice. Of course, removing copyright lines of others
is problematic, hence this commit only removes my own lines and leaves
all others untouched. It might be nicer if sooner or later those could
go away too, making git the only and accurate source of authorship
information.
2018-06-14 10:20:20 +02:00
Lennart Poettering 818bf54632 tree-wide: drop 'This file is part of systemd' blurb
This part of the copyright blurb stems from the GPL use recommendations:

https://www.gnu.org/licenses/gpl-howto.en.html

The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.

hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
2018-06-14 10:20:20 +02:00
Zbigniew Jędrzejewski-Szmek a1230ff972 basic/log: add the log_struct terminator to macro
This way all callers do not need to specify it.
Exhaustively tested by running test-log under valgrind ;)
2018-06-04 13:46:03 +02:00
Lennart Poettering 17cac366ae nspawn: make sure our container PID 1 keeps logging to the original stderr as long as possible
If we log to the pty that is configured as stdin/stdout/stderr of the
container too early we risk filling it up in full before we start
processing the pty from the parent process, resulting in deadlocks.
Let's hence keep a copy of the original tty we were started on before
setting up stdin/stdout/stderr, so that we can log to it, and keep using
it as long as we can.

Since the kernel's pty internal buffer is pretty small this actually
triggered deadlocks when we debug logged at lot from nspawn's child
processes, see: https://github.com/systemd/systemd/pull/9024#issuecomment-390403674

With this change we won't use the pty at all, only the actual payload we
start will, and hence we won't deadlock on it, ever.
2018-05-22 16:52:50 +02:00
Zbigniew Jędrzejewski-Szmek 11a1589223 tree-wide: drop license boilerplate
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.

I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
2018-04-06 18:58:55 +02:00
Franck Bui 848e863acc basic/macros: rename noreturn into _noreturn_ (#8456)
"noreturn" is reserved and can be used in other header files we include:

  [   16s] In file included from /usr/include/gcrypt.h:30:0,
  [   16s]                  from ../src/journal/journal-file.h:26,
  [   16s]                  from ../src/journal/journal-vacuum.c:31:
  [   16s] /usr/include/gpg-error.h:1544:46: error: expected ‘,’ or ‘;’ before ‘)’ token
  [   16s]  void gpgrt_log_bug (const char *fmt, ...)    GPGRT_ATTR_NR_PRINTF(1,2);

Here we include grcrypt.h (which in turns include gpg-error.h) *after* we
"noreturn" was defined in macro.h.
2018-03-15 14:23:46 +09:00
Zbigniew Jędrzejewski-Szmek a3bf71378e basic/log: make log_object_internalv static
It makes the code easier to read, because it's obvious that the function
cannot be called from elsewhere.
2018-02-23 00:13:52 +01:00
Alan Jenkins cc2b9e6b20 rationalize interface for opening/closing logging
log_open_console() did not switch from stderr to /dev/console, when
"always_reopen_console" was set.  It was necessary to call
log_close_console() first.

By contrast, log_open() did switch between e.g. journald and kmsg according
to the value of "prohibit_ipc".

Let's fix log_open() to respect the values of all the log options, and we
can make log_close_*() private.

Also log_close_console() is changed.  There was some precaution, avoiding
closing the console fd if we are not PID 1.  I think commit 48a601fe made
a little mistake in leaving this in, and it only served to confuse
readers :).

Also I changed systemd-shutdown. Now we have log_set_prohibit_ipc(), let's
use it to clarify that systemd-shutdown is not expected to try and log via
journald (which it is about to kill).  We avoided ever asking it to, but
it's more convenient for the reader if they don't have to think about that.
In that sense, it's similar to using assert() to validate a function's
arguments.
2018-01-27 18:01:51 +00:00
Lennart Poettering 6c347d5024 log: remove LOG_TARGET_SAFE pseudo log target
This removes LOG_TARGET_SAFE. It's made redundant by the new
"prohibit-ipc" logging flag, as it used to have a similar effect: avoid
logging to the journal/syslog, i.e. any local services in order to avoid
deadlocks when we lock from PID 1 or its utility processes (such as
generators).

All previous users of LOG_TARGET_SAFE are switched over to the new
setting. This makes things a bit safer for all, as not even the
SYSTEMD_LOG_TARGET env var can be used to accidentally log to the
journal anymore in these programs.
2018-01-24 18:22:56 +01:00
Lennart Poettering 7a3be263d2 log: add brief comment for log_set_open_when_needed() and log_set_always_reopen_console()
These two deserve some explanation...
2018-01-24 18:22:56 +01:00
Lennart Poettering adf47c919a log: add new "prohibit_ipc" flag to logging system
If set, we'll avoid logging to any IPC log targets, i.e. syslog or the
journal, but allow stderr, kmsg, console logging.

This is useful as PID 1 wants to turn this off explicitly as long as the
journal is not up.

Previously we'd open/close the log stream to these services whenever
needed but this is incompatible with the "open_when_needed" logic
introduced in #6915, which might open the log streams whenever it likes,
including possibly inside of the child process we fork off that'll
become journald later on. Hence, let's make this all explicit, and
instead of managing when we open/close log streams add a boolean that
clearly prohibits the IPC targets when needed, so that opening can be
done at any time, but will honour this.

See: #7985
2018-01-24 18:22:56 +01:00
Lennart Poettering 6fdb8de42f log: make log_set_upgrade_syslog_to_journal() take effect immediately
This doesn't matter much, and we don't rely on it, but I think it's much
nicer if we log_set_target() and log_set_upgrade_syslog_to_journal() can
be called in either order and have the same effect.
2018-01-24 18:22:56 +01:00
Lennart Poettering c1e83af84e log: assign the realm to a variable first in log_full_errno_realm()
Let's avoid duplicate evaluation (which might have side-effects) and
assign the realm to an internal variable first, as we need it twice.
2018-01-11 14:44:31 +01:00