Previously, we'd link the unit file into /etc in this case, but that
should only be done if the unit file is not in the search path anyway,
and this is already done implicitly anyway for all enabled unit files,
hence no reason to duplicate this here.
Fixes: #10253
Having systemctl disable/unmask remove all symlinks in /etc and /run is
unintuitive and breaks existing use cases.
systemctl should behave symmetrically.
A "systemctl --runtime unmask" should undo a "systemctl --runtime mask"
action.
Say you have a service, which was masked by the admin in /etc.
If you temporarily want to mask the execution of the service (say in a
script), you'd create a runtime mask via "systemctl --runtime mask".
It is is now no longer possible to undo this temporary mask without
nuking the admin changes, unless you start rm'ing files manually.
While it is useful to be able to remove all enablement/mask symlinks in
one go, this should be done via a separate command line switch, like
"systemctl --all unmask".
This reverts commit 4910b35078.
Fixes: #9393
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.
All users of the macro (except for one, in serialize.c), use the macro in
connection with read_line(), so they must include fileio.h. Let's not play
libc games and require multiple header file to be included for the most common
use of a function.
The removal of def.h includes is not exact. I mostly went over the commits that
switch over to use read_line() and add def.h at the same time and reverted the
addition of def.h in those files.
We want to store either the first error or the total number of changes in 'r'.
Instead, we were overwriting this with the return value from
install_info_traverse().
LGTM complained later in the loop that:
> Comparison is always true because r >= 0.
These lines are generally out-of-date, incomplete and unnecessary.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.
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.
Let's always write "1 << 0", "1 << 1" and so on, except where we need
more than 31 flag bits, where we write "UINT64(1) << 0", and so on to force
64bit values.
The function is similar to path_kill_slashes() but also removes
initial './', trailing '/.', and '/./' in the path.
When the second argument of path_simplify() is false, then it
behaves as the same as path_kill_slashes(). Hence, this also
replaces path_kill_slashes() with path_simplify().
'systemctl disable --runtime' would disable a unit, but only if it was enabled
with '--runtime', and silently do nothing if the unit was enabled persistently.
And similarly 'systemctl disable' would do nothing if the unit was enabled in
/run. This just doesn't seem useful.
This pathch changes enable/disable and mask/unmask to be asymmetrical. enable
and mask create symlinks in /etc or /run, depending on whether --runtime was
specified. disable and unmask remove symlinks from both locations. --runtime
cannot be specified for the disable and unmask verbs.
The advantage is that 'disable' now means that the unit is disabled, period.
And similarly for 'unmask', all masks are removed.
Similarly for preset and preset-all, they now cannot be called with --runtime,
and are asymmetrical: when they enable a unit, symlinks are created in /etc.
When they disable a unit, all symlinks are nuked.
$ systemctl --root=/ enable bluetooth
Created symlink /etc/systemd/system/dbus-org.bluez.service → /usr/lib/systemd/system/bluetooth.service.
Created symlink /etc/systemd/system/bluetooth.target.wants/bluetooth.service → /usr/lib/systemd/system/bluetooth.service.
$ systemctl --root=/ --runtime enable bluetooth
Created symlink /run/systemd/system/dbus-org.bluez.service → /usr/lib/systemd/system/bluetooth.service.
Created symlink /run/systemd/system/bluetooth.target.wants/bluetooth.service → /usr/lib/systemd/system/bluetooth.service.
$ systemctl --root=/ disable bluetooth
Removed /run/systemd/system/bluetooth.target.wants/bluetooth.service.
Removed /run/systemd/system/dbus-org.bluez.service.
Removed /etc/systemd/system/bluetooth.target.wants/bluetooth.service.
Removed /etc/systemd/system/dbus-org.bluez.service.
$ systemctl --root=/ disable --runtime bluetooth
--runtime cannot be used with disable
$ systemctl --root=/ mask --runtime bluetooth
Created symlink /run/systemd/system/bluetooth.service → /dev/null.
$ systemctl --root=/ mask bluetooth
Created symlink /etc/systemd/system/bluetooth.service → /dev/null.
$ systemctl --root=/ unmask bluetooth
Removed /run/systemd/system/bluetooth.service.
Removed /etc/systemd/system/bluetooth.service.
$ systemctl --root=/ unmask --runtime bluetooth
--runtime cannot be used with unmask
$ systemctl --root=/ --runtime enable bluetooth
Created symlink /run/systemd/system/dbus-org.bluez.service → /usr/lib/systemd/system/bluetooth.service.
Created symlink /run/systemd/system/bluetooth.target.wants/bluetooth.service → /usr/lib/systemd/system/bluetooth.service.
$ systemctl --root=/ enable bluetooth
Created symlink /etc/systemd/system/dbus-org.bluez.service → /usr/lib/systemd/system/bluetooth.service.
Created symlink /etc/systemd/system/bluetooth.target.wants/bluetooth.service → /usr/lib/systemd/system/bluetooth.service.
$ systemctl --root=/ preset bluetooth
Removed /run/systemd/system/bluetooth.target.wants/bluetooth.service.
Removed /run/systemd/system/dbus-org.bluez.service.
Removed /etc/systemd/system/bluetooth.target.wants/bluetooth.service.
Removed /etc/systemd/system/dbus-org.bluez.service.
$ systemctl --root=/ preset --runtime bluetooth
--runtime cannot be used with preset
$ systemctl preset-all --runtime
--runtime cannot be used with preset-all
Otherwise querying the preset status of a unit to the user instance gives
incorrect results since in this case the scope used by the manager is
UNIT_FILE_USER.
Previously we were a bit sloppy with the index and size types of arrays,
we'd regularly use unsigned. While I don't think this ever resulted in
real issues I think we should be more careful there and follow a
stricter regime: unless there's a strong reason not to use size_t for
array sizes and indexes, size_t it should be. Any allocations we do
ultimately will use size_t anyway, and converting forth and back between
unsigned and size_t will always be a source of problems.
Note that on 32bit machines "unsigned" and "size_t" are equivalent, and
on 64bit machines our arrays shouldn't grow that large anyway, and if
they do we have a problem, however that kind of overly large allocation
we have protections for usually, but for overflows we do not have that
so much, hence let's add it.
So yeah, it's a story of the current code being already "good enough",
but I think some extra type hygiene is better.
This patch tries to be comprehensive, but it probably isn't and I missed
a few cases. But I guess we can cover that later as we notice it. Among
smaller fixes, this changes:
1. strv_length()' return type becomes size_t
2. the unit file changes array size becomes size_t
3. DNS answer and query array sizes become size_t
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=76745
This drops a good number of type-specific _cleanup_ macros, and patches
all users to just use the generic ones.
In most recent code we abstained from defining type-specific macros, and
this basically removes all those added already, with the exception of
the really low-level ones.
Having explicit macros for this is not too useful, as the expression
without the extra macro is generally just 2ch wider. We should generally
emphesize generic code, unless there are really good reasons for
specific code, hence let's follow this in this case too.
Note that _cleanup_free_ and similar really low-level, libc'ish, Linux
API'ish macros continue to be defined, only the really high-level OO
ones are dropped. From now on this should really be the rule: for really
low-level stuff, such as memory allocation, fd handling and so one, go
ahead and define explicit per-type macros, but for high-level, specific
program code, just use the generic _cleanup_() macro directly, in order
to keep things simple and as readable as possible for the uninitiated.
Note that before this patch some of the APIs (notable libudev ones) were
already used with the high-level macros at some places and with the
generic _cleanup_ macro at others. With this patch we hence unify on the
latter.
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.
The names of drop-in files can be anything as long as they are suffixed
in ".conf", hence don't be stricter than necessary when validating the
names used in symlink chains of such drop-in files.
Also, drop-in files should not be ale to change the type of unit file
itself, i.e. not affect whether it is considered masked or an alias as a
whole.
This adds a flag SEARCH_DROPIN that is passed whenever we load a drop-in
rather the main unit file, and in that case loosen checks and behaviour
we otherwise enforce for the unit file itself. Specifically:
1. If SEARCH_DROPIN is passed we won't change the unit's info->type
field anymore, as that field (which can be REGULAR, MASKED, SYMLINK)
should not be affected by drop-ins, but only by the unit file itself.
2. If SEARCH_DROPIN is passed we will shortcut following of symlink
chains, and not validate the naming of each element in the chain,
since that's irrelevant for drop-ins, and only matters for the unit
file itself.
Or in other words, without this:
1. A symlink /etc/systemd/system/foobar.service.d/20-quux.conf →
/dev/null might have caused the whole of foobar.service to be
considered "masked".
2. A symlink /etc/systemd/system/foobar.service.d/20-quux.conf →
/tmp/miepf might have caused the whole loading of foobar.service to
fail as EINVAL, as "miepf" is not a valid unit name.
This macro will read a pointer of any type, return it, and set the
pointer to NULL. This is useful as an explicit concept of passing
ownership of a memory area between pointers.
This takes inspiration from Rust:
https://doc.rust-lang.org/std/option/enum.Option.html#method.take
and was suggested by Alan Jenkins (@sourcejedi).
It drops ~160 lines of code from our codebase, which makes me like it.
Also, I think it clarifies passing of ownership, and thus helps
readability a bit (at least for the initiated who know the new macro)
Let's add a common implementation for regular file checks, that are
careful to return the right error code (EISDIR/EISLNK/EBADFD) when we
are encountering a wrong file node.
We already print it as part of log_syntax() internal logic, don't print
it again, and in particular, don't print it at the end of log line, such
a strange place.
Follow-up for: 142468d895
The advantage is that is the name is mispellt, cpp will warn us.
$ git grep -Ee "conf.set\('(HAVE|ENABLE)_" -l|xargs sed -r -i "s/conf.set\('(HAVE|ENABLE)_/conf.set10('\1_/"
$ git grep -Ee '#ifn?def (HAVE|ENABLE)' -l|xargs sed -r -i 's/#ifdef (HAVE|ENABLE)/#if \1/; s/#ifndef (HAVE|ENABLE)/#if ! \1/;'
$ git grep -Ee 'if.*defined\(HAVE' -l|xargs sed -i -r 's/defined\((HAVE_[A-Z0-9_]*)\)/\1/g'
$ git grep -Ee 'if.*defined\(ENABLE' -l|xargs sed -i -r 's/defined\((ENABLE_[A-Z0-9_]*)\)/\1/g'
+ manual changes to meson.build
squash! build-sys: use #if Y instead of #ifdef Y everywhere
v2:
- fix incorrect setting of HAVE_LIBIDN2
We would not consider symlinks in /etc/systemd/user/*.{wants,requires}/
towards the user unit being "enabled", because the symlinks were not
located in "config" paths. But this is confusing to users, since those units
are clearly enabled and will be started. So let's muddle the definition of
enablement a bit to include the paths only accessible to root when looking for
enabled user units.
Fixes#4432.
I think this matches the spirit of "indirect" well: the unit
*might* be active, even though it is not "installed" in the
sense of symlinks created based on the [Install] section.
The changes to test-install-root touch the same lines as in the previous
commit; the change in each case is from
assert_se(unit_file_get_state(...) >= 0 && state == UNIT_FILE_ENABLED)
to
assert_se(unit_file_get_state(...) >= 0 && state == UNIT_FILE_DISABLED)
to
assert_se(unit_file_get_state(...) >= 0 && state == UNIT_FILE_INDIRECT)
in the last two commits.
When a unit has a symlink that makes an alias in the filesystem,
but that name is not specified in [Install], it is confusing
is the unit is shown as "enabled". Look only for names specified
in Alias=.
Fixes#6338.
v2:
- Fix indentation.
- Fix checking for normal enablement, when the symlink name is the same as the
unit name. This case wasn't handled properly in v1.
v3:
- Rework the patch to also handle templates properly:
A template templ@.service with DefaultInstance=foo will be considered
enabled only when templ@foo.service symlink is found. Symlinks with
other instance names do not count, which matches the logic for aliases
to normal units. Tests are updated.
All those uses were correct, but I think it's better to be explicit.
Using implicit errno is too error prone, and with this change we can require
(in the sense of a style guideline) that the code is always specified.
Helpful query: git grep -n -P 'log_[^s][a-z]+\(.*%m'
Under specific circumstances it might happen that we can't figure out
where to place our symlinks, for example because we are supposed to
create them in the runtime directory but $XDG_RUNTIME_DIR is not set. In
this case, return -ENXIO instead of hitting an assert().
(Yeah, the error isn't very descriptive, but for now this should at
least be good enough to remove the assert() being hit.)
In some cases there might be unit symlinks in .wants/ or .requires/
directories even though the unit is otherwise fully removed. In this
case, don't fail removal, but still remove the symlinks.
This reworks the symlink marking logic to always add unit files that we
are missing to the changes list, but proceed with any symlink removal
for them. This way we'll still generate useful hints that a unit is
missing if you invoke "systemctl disable idontexist.service", but also
still remove any link to it.
Fixes: #4995
If a unit foobar@.service stored below /usr is instantiated via a
symlink foobar@quux.service also below /usr, then we should consider the
instance statically enabled, while the template itself should continue
to be considered enabled/disabled/static depending on its [Install]
section.
In order to implement this we'll now look for enablement symlinks in all
unit search paths, not just in the config and runtime dirs.
Fixes: #5136
Before this patch, if we'd encounter an instance or template symlink
while traversing a chain of symlinks we'd fill in the instance name and
retry the iteration. This makes no sense if the resulting name is
actually the same as we are coming from, as we'd just spin a couple of
times in the loop, until the UNIT_FILE_FOLLOW_SYMLINK_MAX iteration
limit is hit.
Fix this, by accepted the symlink as it is, if it identical to what we
filled in.
Fixes:
```
touch hola.service
systemctl link $(pwd)/hola.service $(pwd)/hola.service
```
```
==1==ERROR: AddressSanitizer: attempting double-free on 0x60300002c560 in thread T0 (systemd):
#0 0x7fc8c961cb00 in free (/lib64/libasan.so.3+0xc6b00)
#1 0x7fc8c90ebd3b in strv_clear src/basic/strv.c:83
#2 0x7fc8c90ebdb6 in strv_free src/basic/strv.c:89
#3 0x55637c758c77 in strv_freep src/basic/strv.h:37
#4 0x55637c763ba9 in method_enable_unit_files_generic src/core/dbus-manager.c:1960
#5 0x55637c763d16 in method_link_unit_files src/core/dbus-manager.c:2001
#6 0x7fc8c92537ec in method_callbacks_run src/libsystemd/sd-bus/bus-objects.c:418
#7 0x7fc8c9258830 in object_find_and_run src/libsystemd/sd-bus/bus-objects.c:1255
#8 0x7fc8c92594d7 in bus_process_object src/libsystemd/sd-bus/bus-objects.c:1371
#9 0x7fc8c91e7553 in process_message src/libsystemd/sd-bus/sd-bus.c:2563
#10 0x7fc8c91e78ce in process_running src/libsystemd/sd-bus/sd-bus.c:2605
#11 0x7fc8c91e8f61 in bus_process_internal src/libsystemd/sd-bus/sd-bus.c:2837
#12 0x7fc8c91e90d2 in sd_bus_process src/libsystemd/sd-bus/sd-bus.c:2856
#13 0x7fc8c91ea8f9 in io_callback src/libsystemd/sd-bus/sd-bus.c:3126
#14 0x7fc8c928333b in source_dispatch src/libsystemd/sd-event/sd-event.c:2268
#15 0x7fc8c9285cf7 in sd_event_dispatch src/libsystemd/sd-event/sd-event.c:2627
#16 0x7fc8c92865fa in sd_event_run src/libsystemd/sd-event/sd-event.c:2686
#17 0x55637c6b5257 in manager_loop src/core/manager.c:2274
#18 0x55637c6a2194 in main src/core/main.c:1920
#19 0x7fc8c7ac7400 in __libc_start_main (/lib64/libc.so.6+0x20400)
#20 0x55637c697339 in _start (/usr/lib/systemd/systemd+0xcd339)
0x60300002c560 is located 0 bytes inside of 19-byte region [0x60300002c560,0x60300002c573)
freed by thread T0 (systemd) here:
#0 0x7fc8c961cb00 in free (/lib64/libasan.so.3+0xc6b00)
#1 0x7fc8c90ee320 in strv_remove src/basic/strv.c:630
#2 0x7fc8c90ee190 in strv_uniq src/basic/strv.c:602
#3 0x7fc8c9180533 in unit_file_link src/shared/install.c:1996
#4 0x55637c763b25 in method_enable_unit_files_generic src/core/dbus-manager.c:1985
#5 0x55637c763d16 in method_link_unit_files src/core/dbus-manager.c:2001
#6 0x7fc8c92537ec in method_callbacks_run src/libsystemd/sd-bus/bus-objects.c:418
#7 0x7fc8c9258830 in object_find_and_run src/libsystemd/sd-bus/bus-objects.c:1255
#8 0x7fc8c92594d7 in bus_process_object src/libsystemd/sd-bus/bus-objects.c:1371
#9 0x7fc8c91e7553 in process_message src/libsystemd/sd-bus/sd-bus.c:2563
#10 0x7fc8c91e78ce in process_running src/libsystemd/sd-bus/sd-bus.c:2605
#11 0x7fc8c91e8f61 in bus_process_internal src/libsystemd/sd-bus/sd-bus.c:2837
#12 0x7fc8c91e90d2 in sd_bus_process src/libsystemd/sd-bus/sd-bus.c:2856
#13 0x7fc8c91ea8f9 in io_callback src/libsystemd/sd-bus/sd-bus.c:3126
#14 0x7fc8c928333b in source_dispatch src/libsystemd/sd-event/sd-event.c:2268
#15 0x7fc8c9285cf7 in sd_event_dispatch src/libsystemd/sd-event/sd-event.c:2627
#16 0x7fc8c92865fa in sd_event_run src/libsystemd/sd-event/sd-event.c:2686
#17 0x55637c6b5257 in manager_loop src/core/manager.c:2274
#18 0x55637c6a2194 in main src/core/main.c:1920
#19 0x7fc8c7ac7400 in __libc_start_main (/lib64/libc.so.6+0x20400)
previously allocated by thread T0 (systemd) here:
#0 0x7fc8c95b0160 in strdup (/lib64/libasan.so.3+0x5a160)
#1 0x7fc8c90edf32 in strv_extend src/basic/strv.c:552
#2 0x7fc8c923ae41 in bus_message_read_strv_extend src/libsystemd/sd-bus/bus-message.c:5578
#3 0x7fc8c923b0de in sd_bus_message_read_strv src/libsystemd/sd-bus/bus-message.c:5600
#4 0x55637c7639d1 in method_enable_unit_files_generic src/core/dbus-manager.c:1969
#5 0x55637c763d16 in method_link_unit_files src/core/dbus-manager.c:2001
#6 0x7fc8c92537ec in method_callbacks_run src/libsystemd/sd-bus/bus-objects.c:418
#7 0x7fc8c9258830 in object_find_and_run src/libsystemd/sd-bus/bus-objects.c:1255
#8 0x7fc8c92594d7 in bus_process_object src/libsystemd/sd-bus/bus-objects.c:1371
#9 0x7fc8c91e7553 in process_message src/libsystemd/sd-bus/sd-bus.c:2563
#10 0x7fc8c91e78ce in process_running src/libsystemd/sd-bus/sd-bus.c:2605
#11 0x7fc8c91e8f61 in bus_process_internal src/libsystemd/sd-bus/sd-bus.c:2837
#12 0x7fc8c91e90d2 in sd_bus_process src/libsystemd/sd-bus/sd-bus.c:2856
#13 0x7fc8c91ea8f9 in io_callback src/libsystemd/sd-bus/sd-bus.c:3126
#14 0x7fc8c928333b in source_dispatch src/libsystemd/sd-event/sd-event.c:2268
#15 0x7fc8c9285cf7 in sd_event_dispatch src/libsystemd/sd-event/sd-event.c:2627
#16 0x7fc8c92865fa in sd_event_run src/libsystemd/sd-event/sd-event.c:2686
#17 0x55637c6b5257 in manager_loop src/core/manager.c:2274
#18 0x55637c6a2194 in main src/core/main.c:1920
#19 0x7fc8c7ac7400 in __libc_start_main (/lib64/libc.so.6+0x20400)
SUMMARY: AddressSanitizer: double-free (/lib64/libasan.so.3+0xc6b00) in free
==1==ABORTING
```
Closes#5015
Easily reproducible:
1) systemctl mask foo
2) systemctl unmask foo foo
The problem here is that the *i that is put into todo[] is later freed
in strv_uniq(), which is not directly visible from this patch. Somewhere
further in the code, the string that *i pointed to is freed again. That
happens only when multiple services with the same name/path are specified.
This permits "systemctl enable" and "systemctl add-wants" on template
units without any specifications of an instance name, neither specified
on the command line, nor specified in DefaultInstance= field of the
[install] section.
Fixes: #3473
It may be desired by users to know what targets a particular service is
installed into. Improve user friendliness by teaching the is-enabled
command to show such information when used with --full.
This patch makes use of the newly added UnitFileFlags and adds
UNIT_FILE_DRY_RUN flag into it. Since the API had already been modified,
it's now easy to add the new dry-run feature for other commands as
well. As a next step, --dry-run could be added to systemctl, which in
turn might pave the way for a long requested dry-run feature when
running systemctl start.
When a unit file is invalid, we'd return an error without any details:
$ systemctl --root=/ enable testing@instance.service
Failed to enable: Invalid argument.
Fix things to at least print the offending file name:
$ systemctl enable testing@instance.service
Failed to enable unit: File testing@instance.service: Invalid argument
$ systemctl --root=/ enable testing@instance.service
Failed to enable unit, file testing@instance.service: Invalid argument.
A real fix would be to pass back a proper error message from conf-parser.
But this would require major surgery, since conf-parser functions now
simply print log errors, but we would need to return them over the bus.
So let's just print the file name, to indicate where the error is.
(Incomplete) fix for #4210.
Test case:
[Install]
WantedBy= default.target
Also=foobar-unknown.service
Before:
$ systemctl --root=/ enable testing2@instance.service
Failed to enable: No such file or directory.
After
$ ./systemctl --root=/ enable testing2@instance.service
Failed to enable unit, file foobar-unknown.service: No such file or directory.
With the following test case:
[Install]
WantedBy= default.target
Also=foobar-unknown.service
disabling would fail with:
$ ./systemctl --root=/ disable testing.service
Cannot find unit foobar-unknown.service. # this is level debug
Failed to disable: No such file or directory. # this is the error
After the change we proceed:
$ ./systemctl --root=/ disable testing.service
Cannot find unit foobar-unknown.service.
Removed /etc/systemd/system/default.target.wants/testing.service.
This does not affect specifying a missing unit directly:
$ ./systemctl --root=/ disable nosuch.service
Failed to disable: No such file or directory.
It's a common pattern, so add a helper for it. A macro is necessary
because a function that takes a pointer to a pointer would be type specific,
similarly to cleanup functions. Seems better to use a macro.
https://bugzilla.redhat.com/show_bug.cgi?id=1374371
When root was empty or equal to "/", chroot_symlinks_same was called with
root==NULL, and strjoina returned "", so the code thought both paths are equal
even if they were not. Fix that by always providing a non-null first argument
to strjoina.
When told to enable a template unit, and the DefaultInstance specified in that
unit was masked, we would do this. Such a unit cannot be started or loaded, so
reporting successful enabling is misleading and unexpected.
$ systemctl mask getty@tty1
Created symlink /etc/systemd/system/getty@tty1.service → /dev/null.
$ systemctl --root=/ enable getty@tty1
(unchanged)
Failed to enable unit, unit /etc/systemd/system/getty@tty1.service is masked.
$ systemctl --root=/ enable getty@
(before)
Created symlink /etc/systemd/system/getty.target.wants/getty@tty1.service → /usr/lib/systemd/system/getty@.service.
(now)
Failed to enable unit, unit /etc/systemd/system/getty@tty1.service is masked.
The same error is emitted for enable and preset. And an error is emmited, not a
warning, so the failure to enable DefaultInstance is treated the same as if the
instance was specified on the command line. I think that this makes most sense,
for most template units.
Fixes#2513.
A masked unit is listed in Also=:
$ systemctl cat test1 test2
→# /etc/systemd/system/test1.service
[Unit]
Description=test service 1
[Service]
Type=oneshot
ExecStart=/usr/bin/true
[Install]
WantedBy=multi-user.target
Also=test2.service
Alias=alias1.service
→# /dev/null
$ systemctl --root=/ enable test1
(before)
Created symlink /etc/systemd/system/alias1.service → /etc/systemd/system/test1.service.
Created symlink /etc/systemd/system/multi-user.target.wants/test1.service → /etc/systemd/system/test1.service.
The unit files have no installation config (WantedBy, RequiredBy, Also, Alias
settings in the [Install] section, and DefaultInstance for template units).
This means they are not meant to be enabled using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit's
.wants/ or .requires/ directory.
2) A unit's purpose may be to act as a helper for some other unit which has
a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
D-Bus, udev, scripted systemctl call, ...).
4) In case of template units, the unit is meant to be enabled with some
instance name specified.
(after)
Created symlink /etc/systemd/system/alias1.service → /etc/systemd/system/test1.service.
Created symlink /etc/systemd/system/multi-user.target.wants/test1.service → /etc/systemd/system/test1.service.
Unit /etc/systemd/system/test2.service is masked, ignoring.
Running preset-all on a system installed from rpms or even created
using make install would remove and recreate a lot of symlinks, changing
relative to absolute symlinks. In general relative symlinks are nicer,
so there is no reason to change them, and those spurious changes were
obscuring more interesting stuff.
$ make install DESTDIR=/var/tmp/inst1
$ systemctl preset-all --root=/var/tmp/inst1
(before)
Removed /var/tmp/inst1/etc/systemd/system/network-online.target.wants/systemd-networkd-wait-online.service.
Created symlink /var/tmp/inst1/etc/systemd/system/ctrl-alt-del.target → /usr/lib/systemd/system/exit.target.
Removed /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/remote-fs.target.
Created symlink /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/remote-fs.target → /usr/lib/systemd/system/remote-fs.target.
Created symlink /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/machines.target → /usr/lib/systemd/system/machines.target.
Created symlink /var/tmp/inst1/etc/systemd/system/sockets.target.wants/systemd-journal-remote.socket → /usr/lib/systemd/system/systemd-journal-remote.socket.
Removed /var/tmp/inst1/etc/systemd/system/sockets.target.wants/systemd-networkd.socket.
Created symlink /var/tmp/inst1/etc/systemd/system/sockets.target.wants/systemd-networkd.socket → /usr/lib/systemd/system/systemd-networkd.socket.
Removed /var/tmp/inst1/etc/systemd/system/getty.target.wants/getty@tty1.service.
Created symlink /var/tmp/inst1/etc/systemd/system/getty.target.wants/getty@tty1.service → /usr/lib/systemd/system/getty@.service.
Created symlink /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/systemd-journal-upload.service → /usr/lib/systemd/system/systemd-journal-upload.service.
Removed /var/tmp/inst1/etc/systemd/system/sysinit.target.wants/systemd-timesyncd.service.
Created symlink /var/tmp/inst1/etc/systemd/system/sysinit.target.wants/systemd-timesyncd.service → /usr/lib/systemd/system/systemd-timesyncd.service.
Removed /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/systemd-resolved.service.
Created symlink /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/systemd-resolved.service → /usr/lib/systemd/system/systemd-resolved.service.
Removed /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/systemd-networkd.service.
Created symlink /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/systemd-networkd.service → /usr/lib/systemd/system/systemd-networkd.service.
(after)
Removed /var/tmp/inst1/etc/systemd/system/network-online.target.wants/systemd-networkd-wait-online.service.
Created symlink /var/tmp/inst1/etc/systemd/system/ctrl-alt-del.target → /usr/lib/systemd/system/exit.target.
Created symlink /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/machines.target → /usr/lib/systemd/system/machines.target.
Created symlink /var/tmp/inst1/etc/systemd/system/sockets.target.wants/systemd-journal-remote.socket → /usr/lib/systemd/system/systemd-journal-remote.socket.
Created symlink /var/tmp/inst1/etc/systemd/system/multi-user.target.wants/systemd-journal-upload.service → /usr/lib/systemd/system/systemd-journal-upload.service.
Before, when interating over unit files during preset-all, behaviour was the
following:
- if we hit the real unit name first, presets were queried for that name, and
that unit was enabled or disabled accordingly,
- if we hit an alias first (one of the symlinks chaining to the real unit), we
checked the presets using the symlink name, and then proceeded to enable or
disable the real unit.
E.g. for systemd-networkd.service we have the alias dbus-org.freedesktop.network1.service
(/usr/lib/systemd/system/dbus-org.freedesktop.network1.service), but the preset
is only for the systemd-networkd.service name. The service would be enabled or
disabled pseudorandomly depending on the order of iteration.
For "preset", behaviour was analogous: preset on the alias name disabled the
service (following the default disable policy), preset on the "real" name
applied the presets.
With the patch, for "preset" and "preset-all" we silently skip symlinks. This
gives mostly the right behaviour, with the limitation that presets on aliases
are ignored. I think that presets on aliases are not that common (at least my
preset files on Fedora don't exhibit any such usage), and should not be
necessary, since whoever installs the preset can just refer to the real unit
file. It would be possible to overcome this limitation by gathering a list of
names of a unit first, and then checking whether *any* of the names matches the
presets list. That would require a significant redesign of the code, and be
a lot slower (since we would have to fully read all unit directories to preset
one unit) to so I'm not doing that for now.
With this patch, two properties are satisfied:
- preset-all and preset are idempotent, and the second and subsequent invocations
do not produce any changes,
- preset-all and preset for a specific name produce the same state for that unit.
Fixes#3616.
Under NixOS, the config_path /etc/systemd/system is a symlink to
/etc/static/systemd/system. Commands such as `systemctl list-unit-files`
and `systemctl is-enabled` did not work as the symlink was not followed.
This does not affect how symlinks are treated within the config_path
directory.
User expectations are broken when "systemctl enable /some/path/service.service"
behaves differently to "systemctl link ..." followed by "systemctl enable".
From user's POV, "enable" with the full path just combines the two steps into
one.
Fixes#3010.
If for whatever reason the file system is "corrupted", we want
to be resilient and ignore the error, as long as we can load the units
from a different place.
Arch bug https://bugs.archlinux.org/task/49547.
A user had an ntfs symlink (essentially a file) instead of a directory after
restoring from backup. We should just ignore that like we would treat a missing
directory, for general resiliency.
We should treat permission errors similarly. For example an unreadable
/usr/local/lib directory would prevent (user) instances of systemd from
loading any units. It seems better to continue.
That function doesn't draw anything on it's own, just returns a string, which
sometimes is more than one character. Also remove "DRAW_" prefix from character
names, TREE_* and ARROW and BLACK_CIRCLE are unambigous on their own, don't
draw anything, and are always used as an argument to special_glyph().
Rename "DASH" to "MDASH", as there's more than one type of dash.
It's quite a bit shorter and just as readable.
(The full sentence with "pointing to" was added to replace a text that used
"ln -s %s %s". Using the "ln" syntax is indeed unclear, because it's not
obvious which is the source and which is the target, and because symlink(2)
uses the opposite order to ln(1). But with the unicode arrow there should
be no ambiguity.)
Executing 'systemctl enable' on the same unit twice would cause
a warning about a missing [Install] section to be printed. To avoid
this, count all symlinks that "would" be created, and return 1
no matter if we actually created a symlink or skipped creation because
it already exists.
This fixes 'preset-all' with a unit that is a dangling symlink.
$ systemctl --root=/ preset-all
Unit syslog.service is an alias to a unit that is not present, ignoring.
Unit auditd.service is masked, ignoring.
Unit NetworkManager.service is masked, ignoring.
$ systemctl --root=/ preset foobar.service
Cannot find unit foobar.service.
Failed to preset: No such file or directory.
$ systemctl --root=/ preset foobar@.service
Cannot find unit foobar@.service.
Failed to preset: No such file or directory.
$ systemctl --root=/ preset foobar@blah.service
Cannot find unit foobar@blah.service or foobar@.service.
Failed to preset: No such file or directory.
The previous implementation traversed the various config directories,
walking the preset files and parsing each line to determine if a service
should be enabled or disabled. It did this for every service which
resulted in many more file operations than neccessary.
This approach parses each of the preset entries into an array which is
then used to check if each service should be enabled or disabled.
A downside is that a warning about missing [Install] is printed:
$ systemctl --root=/ enable mnt-test.mount
[/etc/systemd/system/mnt-test.mount:5] Aliases are not allowed for mount units, ignoring.
The unit files have no installation config (WantedBy, RequiredBy, Also, Alias
settings in the [Install] section, and DefaultInstance for template units).
This means they are not meant to be enabled using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit's
.wants/ or .requires/ directory.
2) A unit's purpose may be to act as a helper for some other unit which has
a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
D-Bus, udev, scripted systemctl call, ...).
4) In case of template units, the unit is meant to be enabled with some
instance name specified.
That's a bit misleading, but I don't see an easy way to fix this. But
the situation is similar for many other parsing errors, so maybe that's
OK.
