sd-device: initialize variables to avoid warning The code is correct, assuming that the kernel does not feed us garbled data. Let's initialize those variables to avoid the warning anyway.

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.

parse-util: introduce parse_ifindex() and make use of it everywhere We have enough places where we parse an ifindex, hence introduce a proper parsing function for it, that verifies all parameters.

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

util-lib: split stat()/statfs()/stavfs() related calls into stat-util.[ch]

util-lib: move a number of fs operations into fs-util.[ch]

util-lib: split string parsing related calls from util.[ch] into parse-util.[ch]

util-lib: split out fd-related operations into fd-util.[ch] There are more than enough to deserve their own .c file, hence move them over.

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.

libsystemd: sd-device - translate / vs. ! in sysname The kernel replaces '/' in device names with '!', we translate that back to '/' in sysname, when taking sysname as input, we should translate it back again.

sd-device: fix format strings after conversion to log_*_errno() Use %m where previously %s was used together with strerrno(). Fixes: e53fc357a9b "tree-wide: remove a number of invocations of strerror() and replace by %m"

tree-wide: add missing errno arguments to log_*_errno() A few of the recent conversions to log_*_errno() were missing the errno value arguments. Fixes: e53fc357a9b "tree-wide: remove a number of invocations of strerror() and replace by %m"

tree-wide: remove a number of invocations of strerror() and replace by %m Let's clean up our tree a bit, and reduce invocations of the thread-unsafe strerror() by replacing it with printf()'s %m specifier.

sd-device: never return NULL+0 It is highly confusing if a getter function returns 0, but the value is set to NULL. This, right now, triggers assertions as code relies on the returned values to be non-NULL. Like with sd-bus-creds and friends, return 0 only if a value is actually available. Discussed with Tom, and actually fixes real bugs as in #512.

hashmap: fix iterators to not skip entries Currently, the HASHMAP iterators stop at the first NULL entry in a hashmap. This is non-obvious and breaks users like sd-device, which legitimately store NULL values in a hashmap. Fix all the iterators by taking a pointer to the value storage, instead of returning it. The iterators now return a boolean that tells whether the end of the list was reached. Current users of HASHMAP_FOREACH() are *NOT* changed to explicitly check for NULL. If it turns out, there were users that inserted NULL into hashmaps, but didn't properly check for it during iteration, then we really want to find those and fix them.

fix double semicolon typo

sd-device: get_driver - remember if a device does not have a driver Don't try to read it again.

sd-device: get_subsystem - don't complain if a device does not have a subsystem

sd-device: fix return codes on error asprintf() does not set errno.

sd-device: don't retry loading uevent/db files more than once If for whatever reason there was nothing to load or loading failed, don't keep trying.

sd-device: don't complain if the uevent file is missing Only 'real' devices are required to have an uevent file.

udevd: fix REMOVE handling This reverts b67f944. Lazy loading of device properties does not work for devices that are received over netlink, as these are sealed. Reinstate the unconditional loading of the device db. Reported by: Mantas Mikulėnas <grawity@gmail.com>.

sd-device: set_syspath - return ENODEV when passed something that is not a device

sd-device: uniformly handle missing devices sd_device_new_from_* now returns -ENODEV when the device does not exist, and the enumerator silently drops these errors as missing devices is exepected.

sd-devcie: fix typo

sd-device: fix reading of subsystem

sd-device: allow uevent files to be write-only

device: fix sysattr newline cutter Right now, we always drop the last character of all values we write to sysfs. Fix this!

sd-device: get_sysattr_value - don't leak returned value This was getting leaked as a copy was added to the hashmap, simply add the returned value instead. This should fix CID #1292806.

sd-device: initialize variable sysnum would not be initialized if sysname had no trailing digits.

libsystemd: add sd-device library This provides equivalent functionality to libudev-device, but in the systemd style. The public API only caters to creating sd_device objects from for devices that already exist in /sys, there is no support for listening for monitoring events or creating devices received over the udev netlink protocol. The private API contains the necessary functionality to make sd-device a drop-in replacement for libudev-device, but which we would not otherwise want to export.