As sd_device_get_sysattr_value() may be already used to read uevent
file. The read value of uevent file may be usually quite different
from the action string.
There are three calls of device_cache_sysattr_value(). Two of them are
just caching the value. Hence, let's ignore its failure, and propagate
original error code.
One exception is the last call in sd_device_get_sysattr_value().
Unfortunately, it returns `const char *` instead of `char *`. So,
sd_device object must have the reference of the returned value.
Hence, error in updating the cache by device_cache_sysattr_value()
is critical, and we need to propagate the error in that case.
It is not intuitive, and I do not know why the function behave so.
But let's keep that behavior for compatibility, as such behavior
may be already used explicitly by callers.
To make sd-device properly usable for all programs we need to provide an
API for the "action" field of an event, it's one of the most relevant
ones, and it was so far missing.
This also adds sd_device_get_seqnum(), which isn't that interesting,
except for generating pretty debug output, which we use it ourselves
for.
This also makes device_new_from_stat_rdev() public, as it is truly
useful, as we can see in our own uses of it, and I think is fairly
generic to show up in the public APIs.
Apparently, in our current public headers (i.e. those called sd-*.h) we
suffixed typedefs that we use as values with _t, but we didn't do this
for enum typedefs. Fix that while this stuff is not actually public yet.
With this scheme "value typedefs" now end systematically in _t, and
"object typedefs" (i.e. structures that are typically passed around via
pointers and not values) do not.
No code changes, just some renaming.
The existing set_offline() short-circuit erroneously included
when f->archive was true and header->state was STATE_OFFLINE.
This commit makes the short-circuit f->archive aware, so it will
only catch scenarios where there's not an offlining in progress
and the header state matches the target state of either archived
or offline.
Fixes https://github.com/systemd/systemd/issues/17770
If the cleanup function returns the appropriate type, use that to reset the
variable. For other functions (usually the foreign ones which return void), add
an explicit value to reset to.
This causes a bit of code churn, but I think it might be worth it. In a
following patch static destructors will be called from a fuzzer, and this
change allows them to be called multiple times. But I think such a change might
help with detecting unitialized code reuse too. We hit various bugs like this,
and things are more obvious when a pointer has been set to NULL.
I was worried whether this change increases text size, but it doesn't seem to:
-Dbuildtype=debug:
before "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494520 Feb 16 15:06 build/systemd*
after "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494576 Feb 16 15:10 build/systemd*
now:
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494640 Feb 16 15:15 build/systemd*
-Dbuildtype=release:
before "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:09 build-rawhide/systemd*
after "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:10 build-rawhide/systemd*
now:
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:16 build-rawhide/systemd*
I would expect that the compiler would be able to elide the setting of a
variable if the variable is never used again. And this seems to be the case:
in optimized builds there is no change in size whatsoever. And the change in
size in unoptimized build is negligible.
Something strange is happening with size of libsystemd: it's bigger in
optimized builds. Something to figure out, but unrelated to this patch.
I started working on this because I wanted to change how
DEFINE_TRIVIAL_CLEANUP_FUNC is defined. Even independently of that change, it's
nice to make make things more consistent and predictable.
A previous commit made sure that when one of our own packets is looped
back to us, we ignore it. But let's go one step further, and refuse
operation if we notice the server we talk to is our own. This way we
won't generate unnecessary traffic and can return a cleaner error.
Fixes: #17413
It's rather convenient to be able to read all three types with this function.
Strictly speaking this change is not fully compatible, in case someone was
relying on sd_bus_message_read_strv() returning an error for anything except
"as", but I hope nobody was doing that.
Let's use uint32_t everywhere to maintain the seqno, since that's what
the kernel does. Prviously in the reply_callback logic we used 64bit,
for no apparent reason.
Using 32bit also provides us with the benefit that we can avoid using
uint64_hash_ops, and can use trivial_hash_ops instead for the reply
hashmap, so that we can store the seqno in the key pointer directly.
While we are at it, let's make sure we never run into serial collisions
internally (32bit is a lot, but not that much), and let's put a limit on
outstanding serials, to catch programming errors.
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.
A hole was/is present after the booleans, so changing them to be one byte each
doesn't change the structure size (122 bits on amd64). If we add more stuff
later, it might make sense to turn some of those into bitfields again. For now,
let's take the easy route. EINVAL fits into type now.
Code size it minimally reduced:
-rwxrwxr-x 1 zbyszek zbyszek 4109792 Feb 10 14:00 build/libsystemd.so.0.30.0
-rwxrwxr-x 1 zbyszek zbyszek 4109712 Feb 10 14:01 build/libsystemd.so.0.30.0
By rearranging the fields, we can avoid one of the holes (on amd64).
By adding more space for .type, -EINVAL can be used as a value later on.
The structure is reduced from 96 to 88 bytes (on amd64).
Text size is also smaller:
-rwxrwxr-x 1 zbyszek zbyszek 4109832 Feb 9 19:50 build/libsystemd.so.0.30.0
-rwxrwxr-x 1 zbyszek zbyszek 4109792 Feb 9 19:51 build/libsystemd.so.0.30.0
Annika Wickert
Yu Watanabe
Lennart Poettering
Vito Caputo
Zbigniew Jędrzejewski-Szmek