tree-wide: remove Emacs lines from all files This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.

tree-wide: expose "p"-suffix unref calls in public APIs to make gcc cleanup easy GLIB has recently started to officially support the gcc cleanup attribute in its public API, hence let's do the same for our APIs. With this patch we'll define an xyz_unrefp() call for each public xyz_unref() call, to make it easy to use inside a __attribute__((cleanup())) expression. Then, all code is ported over to make use of this. The new calls are also documented in the man pages, with examples how to use them (well, I only added docs where the _unref() call itself already had docs, and the examples, only cover sd_bus_unrefp() and sd_event_unrefp()). This also renames sd_lldp_free() to sd_lldp_unref(), since that's how we tend to call our destructors these days. Note that this defines no public macro that wraps gcc's attribute and makes it easier to use. While I think it's our duty in the library to make our stuff easy to use, I figure it's not our duty to make gcc's own features easy to use on its own. Most likely, client code which wants to make use of this should define its own: #define _cleanup_(function) __attribute__((cleanup(function))) Or similar, to make the gcc feature easier to use. Making this logic public has the benefit that we can remove three header files whose only purpose was to define these functions internally. See #2008.

tree-wide: sort includes Sort the includes accoding to the new coding style.

util-lib: split out allocation calls into alloc-util.[ch]

util-lib: split our string related calls from util.[ch] into its own file string-util.[ch] There are more than enough calls doing string manipulations to deserve its own files, hence do something about it. This patch also sorts the #include blocks of all files that needed to be updated, according to the sorting suggestions from CODING_STYLE. Since pretty much every file needs our string manipulation functions this effectively means that most files have sorted #include blocks now. Also touches a few unrelated include files.

hashmap: refactor hash_func All our hash functions are based on siphash24(), factor out siphash_init() and siphash24_finalize() and pass the siphash state to the hash functions rather than the hash key. This simplifies the hash functions, and in particular makes composition simpler as calling siphash24_compress() repeatedly on separate chunks of input has the same effect as first concatenating the input and then calling siphash23_compress() on the result.

sd-bus: make introspection data non-recursive Currently, our introspection data looks like this: <node> <interface name="org.freedesktop.DBus.Peer"> ... </interface> <interface name="org.freedesktop.DBus.Introspectable"> ... </interface> <interface name="org.freedesktop.DBus.Properties"> ... </interface> <node name="org"/> <node name="org/freedesktop"/> <node name="org/freedesktop/login1"/> <node name="org/freedesktop/login1/user"/> <node name="org/freedesktop/login1/user/self"/> <node name="org/freedesktop/login1/user/_1000"/> <node name="org/freedesktop/login1/seat"/> <node name="org/freedesktop/login1/seat/self"/> <node name="org/freedesktop/login1/seat/seat0"/> <node name="org/freedesktop/login1/session"/> <node name="org/freedesktop/login1/session/self"/> <node name="org/freedesktop/login1/session/c1"/> </node> (ordered alphabetically for better visibility) This is grossly incorrect. The spec says that we're allowed to return non-directed children, however, it does not allow us to return data recursively in multiple parents. If we return "org", then we must not return anything else that starts with "org/". It is unclear, whether we can include child-nodes as a tree. Moreover, it is usually not what the caller wants. Hence, this patch changes sd-bus to never return introspection data recursively. Instead, only a single child-layer is returned. This patch relies on enumerators to never return hierarchies. If someone registers an enumerator via sd_bus_add_enumerator, they better register sub-enumerators if they support *TRUE* hierarchies. Each enumerator is treated as a single layer and not filtered. Enumerators are still allowed to return nested data. However, that data is still required to be a single hierarchy. For instance, returning "/org/foo" and "/com/bar" is fine, but including "/com" or "/org" in that dataset is not. This should be the default for enumerators and I see no reason to filter in sd-bus. Moreover, filtering that data-set would require to sort the strv by path and then do prefix-filtering. This is O(n log n), which would be fine, but still better to avoid. Fixes #664.

Revert "sd-bus: do not connect to dbus-1 socket when kdbus is available" This reverts commit d4d00020d6ad855d65d31020fefa5003e1bb477f. The idea of the commit is broken and needs to be reworked. We really cannot reduce the bus-addresses to a single address. We always will have systemd with native clients and legacy clients at the same time, so we also need both addresses at the same time.

sd-bus: introduce new SD_BUS_VTABLE_PROPERTY_EXPLICIT flag This allows marking properties as "explicit". Properties marked like this are included in the introspection, but are avoided in GetAll() property queries, PropertiesChanged() signals and in in GetManaged() object manager calls and InterfacesAdded() signals. Expensive properties may be marked that way, and they will be retrievable when explicitly being requested, but never in "blanket" all-property queries and signals. This flag may be combined with the flags for "const" and "emit-validation" properties, but not with "emit-validation", as that is only useful for properties whose value shall be sent in "blanket" all-property signals. The "explicit" flag is also exposed in the introspection data via a new annotation.

Revert "sd-bus: include queried path in GetManagedObjects" This reverts commit 92d16a53e385781a55d9231d9f8f89c1747ab0e4. As it turns out, this is not how ObjectManager is supposed to work. It is just a special behavior of BlueZ, but no-one else implements it this way. Revert the patch as discussed on github, and as such revert to the previous behavior (as described in the spec).

sd-bus: do not connect to dbus-1 socket when kdbus is available We should not fall back to dbus-1 and connect to the proxy when kdbus returns an error that indicates that kdbus is running but just does not accept new connections because of quota limits or something similar. Using is_kdbus_available() in libsystemd/ requires it to move from shared/ to libsystemd/. Based on a patch from David Herrmann: https://github.com/systemd/systemd/pull/886

sd-bus: fix path of object-manager signals Each signal of the ObjectManager interface carries the path of the object in question as an argument. Therefore, a caller will deduce the object this signal is generated for, by parsing the _argument_. A caller will *not* use the object-path of the message itself (i.e., message->path). This is done on purpose, so the caller can rely on message->path to be the path of the actual object-manager that generated this signal, instead of the path of the object that triggered this signal. This commit fixes all InterfacesAdded/Removed signals to use the path of the closest object-manager as message->path. 'closest' in this case means closest parent with at least one object-manager registered. This fix raises the question what happens if we stack object-managers in a hierarchy. Two implementations are possible: First, we report each object only on the nearest object-manager. Second, we report it on each parent object-manager. This patch chooses the former. This is compatible with other existing ObjectManager implementations, which are required to call GetManagedObjects() recursively on each object they find, which implements the ObjectManager interface.

sd-bus: add 'offset' member for vtable methods Defaults to zero, which retains the current behaviour. Fixes #577

sd-bus: fix object tree to be deeper than 2 levels So right now our object-tree is limited to 2 levels at most ('/' and '/foo/...../bar'). We never link any intermediate levels, even though that was clearly the plan. Fix the bus_node_allocate() helper to actually link all intermediate nodes, too, not just the root node. This fixes a simple inverse ptr-diff bug. The downside of this fix is that we clearly never tested (nor used) the object tree in any way. The only reason that the introspection works is that our enumerators shortcut the object tree. Lets see whether that code actually works.. Thanks to: Nathaniel McCallum <nathaniel@themccallums.org> ..for reporting this. See #524 for an actual example code.

sd-bus: include queried path in GetManagedObjects If GetManagedObjects is called on /foo/bar, then it should also include the object /foo/bar, if it exists. Right now, we only include objects underneath /foo/bar/. This follows the behavior of existing dbus implementations. Obsoletes #527 and fixes #525. Reported by: Nathaniel McCallum

export sd_bus_object_added() / _removed() Fixes #306.

sd-bus: drop bus parameter from message callback prototype This should simplify the prototype a bit. The bus parameter is redundant in most cases, and in the few where it matters it can be derived from the message via sd_bus_message_get_bus().

bus: add sd_bus_emit_object_{added/removed}() This implements two new helpers, discussed on systemd-devel about 1 year ago: sd_bus_emit_object_added() sd_bus_emit_object_removed() Both calls are equivalent to their respective counterpart sd_bus_emit_interfaces_{added/removed}(), but can figure out the list of interfaces themselves, instead of requiring the caller to provide them. Furthermore, both calls properly deal with builtin interfaces provided via org.freedesktop.DBus.* and alike. Both calls simply traverse a node and all its parent nodes to figure out a list of all interfaces registered as vtable or fallback. It then appends each of them, similar to the interfaces_{added/removed}() helpers. Note that interfaces_{added/removed}() runs a parent traversal for *each* passed interface. Therefore, it can simply bail out, once it found a parent node that implements a given interface. With object_{added/removed}() we cannot know the registered interfaces in advance, thus, we cannot run one traversal per node. Instead, we run a single traversal and remember all interfaces that we added. Therefore, a child-interface overrides all conflicting parent-interfaces. We keep a "Set *s" context to track those while climbing up the tree.

bus: remove spurious include of <sys/capability.h> They do not use any functions from libcap directly. The CAP_SYS_ADMIN constant in use by bus-objects.c comes from <linux/capability.h> imported through "missing.h". The "missing.h" header is imported through "util.h" which gets imported in "bus-util.h". Tested that everything builds cleanly after this change.

sd-bus: create clean error when a property Set() call with incorrect signature is passed in

sd-bus: refuse properties that claim to be both writable and constant at the same time

bus: fix error leak in bus_node_exists() If we call into user callbacks, we must always propagate possible errors. Fix bus_node_exists() to do that and adjust the callers (which already partially propagated the error). Also speed up that function by first checking for registered enumerators and/or object-managers.

bus: never respond to GetManagedObjects() on sub-paths The dbus-spec clearly specifies that GetManagedObjects() should only work on the root-path of an object-tree. But on that path, it works regardless whether there are any objects available or not. We could, technically, define all sub-paths as a root-path of its own sub-tree. However, if we do that, we enter undefined territory: Imagine only a fallback vtable is registered. We want GetManagedObjects() to *NOT* fail with UNKNOWN_METHOD if it is called on a valid sub-tree of the fallback. On the other hand, we don't want it to work on arbitrary sub-tree. Something like: /path/to/fallback/foobar/foobar/foobar/invalid/foobar should not work. However, there is no way to know which paths on a fallback are valid without looking at there registered objects. If no objects are registered, we have no way to figure it out. Therefore, we now try to follow the dbus spec by only returning valid data on registered root-paths. We treat each path as root which was registered an object-manager on via add_object_manager(). So applications can now directly control which paths to place an object-manager on. We also fix the introspection to not return object-manager interfaces on non-root paths. Also fixes some dead-code paths initially reported by Philippe De Swert.

hashmap: introduce hash_ops to make struct Hashmap smaller It is redundant to store 'hash' and 'compare' function pointers in struct Hashmap separately. The functions always comprise a pair. Store a single pointer to struct hash_ops instead. systemd keeps hundreds of hashmaps, so this saves a little bit of memory.

sd-bus: add API to query which handler/callback is currently being dispatched

sd-bus,log: remove unused variables

sd-bus: add API to check if a client has privileges This is a generalization of the vtable privilege check we already have, but exported, and hence useful when preparing for a polkit change. This will deal with the complexity that on dbus1 one cannot trust the capability field we retrieve via the bus, since it is read via /proc/$$/stat (and thus might be out-of-date) rather than directly from the message (like on kdbus) or bus connection (as for uid creds on dbus1). Also, port over all code to this new API.

bus: fix unitialized variable access in error path

sd-bus: always keep slot reference while dispatching callback Also, make sure we automatically destroy reply callbacks that are floating.

sd-bus: introduce sd_bus_slot objects encapsulating callbacks or vtables attached to a bus connection This makes callback behaviour more like sd-event or sd-resolve, and creates proper object for unregistering callbacks. Taking the refernce to the slot is optional. If not taken life time of the slot will be bound to the underlying bus object (or in the case of an async call until the reply has been recieved).

bus: simplification

sd-bus: don't use assert_return() to check for disconnected bus connections A terminated connection is a runtime error and not a developer mistake, hence don't use assert_return() to check for it.

sd-bus: add proper monitoring API

libsystemd: fix compiler warning in property_get_set_callbacks_run() gcc (4.8.2, arm) doesn't understand that vtable_property_get_userdata() will always set 'u' when it returns > 0. Hence, the warning is bogus, but anyway. src/libsystemd/sd-bus/bus-objects.c:510:19: warning: 'u' may be used uninitialized in this function [-Wmaybe-uninitialized] (and yes, indeed, even the reported line numbers are bogus in this case)

api: in constructor function calls, always put the returned object pointer first (or second) Previously the returned object of constructor functions where sometimes returned as last, sometimes as first and sometimes as second parameter. Let's clean this up a bit. Here are the new rules: 1. The object the new object is derived from is put first, if there is any 2. The object we are creating will be returned in the next arguments 3. This is followed by any additional arguments Rationale: For functions that operate on an object we always put that object first. Constructors should probably not be too different in this regard. Also, if the additional parameters might want to use varargs which suggests to put them last. Note that this new scheme only applies to constructor functions, not to all other functions. We do give a lot of freedom for those. Note that this commit only changes the order of the new functions we added, for old ones we accept the wrong order and leave it like that.

libsystemd: split up into subdirs We still only produce on .so, but let's keep the sources separate to make things a bit less messy.