The StartServiceByName() call was provided by dbus-daemon to activate a
service without sending a message. On receiption, dbus-daemon schedules
an activation request (different modes are supported) and sends back the
reply once activation is done.
With kdbus, we marked StartServiceByName() as deprecated. There is no
real reason to start services explicitly. Instead, applications should
just *use* the service and rely on it being activated implicitly.
However, we provide compatibility with dbus-daemon and implement
StartServiceByName() on the proxy via a call to
org.freedesktop.DBus.Peer.Ping() on the destination. This will activate
the peer implicitly as part of the no-op Ping() method call (regardless
whether the peer actually implements that call).
Now, the problem is, StartServiceByName() was synchronous on dbus-daemon
but isn't on bus-proxy. Hence, on return, there is no guarantee that
ListNames includes the activated name. As this is required by some
applications, we need to make this synchronous.
This patch makes the proxy track the Ping() method call and send the
reply of StartServiceByName() only once Ping() returned. We do not look
at possible errors of Ping(), as there is no strict requirement for the
peer to implement org.freedesktop.DBus.Peer. Furthermore, any interesting
error should have already been caught by sd_bus_send() before.
Note:
This race was triggered by gdbus. The gdbus-proxy implementation
relies on a name to be available after StartServiceByName()
returns. This is highly fragile and should be dropped by gdbus.
Even if the call is synchronous, there is no reason whatsoever to
assume the service did not exit-on-idle before ListNames()
returns.
However, this race is much less likely than the startup race, so
we try to be compatible to dbus-daemon now.
AC_CHECK_FILE fails when cross-compiling. It is intended to be used to
check for files that are used at runtime during build time (e.g.
/etc/passwd, /dev/*) [1]. For files which are only used at build time
'test -f' is sufficient.
[1]: https://lists.gnu.org/archive/html/autoconf/2000-10/msg00018.html
NameAcquired and NameLost are directed signals. Never ever filter them on
dbus1. On dbus1, filters *exclusively* apply to broadcasts! Hence, we
must always forward directed signals unconditionally!
Probably a typo, checking 'ret' instead of the return value 'p'. This
might cause the function to return failure, even though it succeeded.
Furthermore, it might leak resources.
We *must not* assume that an entry returned by KDBUS_CMD_LIST only
carries a single KDBUS_ITEM_OWNED_NAME. Similarly, we already parse
multiple such items for message-metadata, so make sure we support the
same on KDBUS_CMD_LIST.
By relying on the kernel to return all names separately, we limit the
kernel API significantly. Stop this and let the kernel decide how to
return its data.
Some places invoked fflush() directly with their own manual error
checking, let's unify all that by using fflush_and_check().
This also unifies the general error paths of fflush()+rename() file
writers.
This patch fixes the size of networkd
Bug #775
before:
size systemd-networkd
text data bss dec hex filename
1493755 8424392 2337 9920484 975fe4 systemd-networkd
After
$ size systemd-networkd
text data bss dec hex filename
1493555 35752 2337 1531644 175efc systemd-networkd
The gvariant root container contains a 'variant' at the end, which embeds
the whole message body. This variant *must* contain a structure so we are
compatible to dbus1. Otherwise, it could encode at most 1 type, instead
of a full signature.
Our gvariant message parser already parses the variant-content as a
structure, so we're mostly good. However, it does *not* include the
opening and closing parantheses, nor does it parse them.
This patch fixes the decoder to verify a message contains the
parantheses, and also make the encoder add those parantheses into the
marshaled message.
If c->item_size is 0, the next item to parse in a structure is empty.
However, this also implies that the signature must be empty. The latter
case is already handled just fine by enter_struct_or_dict_entry() so
there is no reason to handle the same case in the caller.
Right now sd_bus_message_skip() will abort execution if passed a
signature of the unary type "()". Regardless whether this should be
supported or not, we really must not abort. Drop the incorrect assertion
and add a test-case for this.
