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2016-10-07core: add "invocation ID" concept to service managerLennart Poettering
This adds a new invocation ID concept to the service manager. The invocation ID identifies each runtime cycle of a unit uniquely. A new randomized 128bit ID is generated each time a unit moves from and inactive to an activating or active state. The primary usecase for this concept is to connect the runtime data PID 1 maintains about a service with the offline data the journal stores about it. Previously we'd use the unit name plus start/stop times, which however is highly racy since the journal will generally process log data after the service already ended. The "invocation ID" kinda matches the "boot ID" concept of the Linux kernel, except that it applies to an individual unit instead of the whole system. The invocation ID is passed to the activated processes as environment variable. It is additionally stored as extended attribute on the cgroup of the unit. The latter is used by journald to automatically retrieve it for each log logged message and attach it to the log entry. The environment variable is very easily accessible, even for unprivileged services. OTOH the extended attribute is only accessible to privileged processes (this is because cgroupfs only supports the "trusted." xattr namespace, not "user."). The environment variable may be altered by services, the extended attribute may not be, hence is the better choice for the journal. Note that reading the invocation ID off the extended attribute from journald is racy, similar to the way reading the unit name for a logging process is. This patch adds APIs to read the invocation ID to sd-id128: sd_id128_get_invocation() may be used in a similar fashion to sd_id128_get_boot(). PID1's own logging is updated to always include the invocation ID when it logs information about a unit. A new bus call GetUnitByInvocationID() is added that allows retrieving a bus path to a unit by its invocation ID. The bus path is built using the invocation ID, thus providing a path for referring to a unit that is valid only for the current runtime cycleof it. Outlook for the future: should the kernel eventually allow passing of cgroup information along AF_UNIX/SOCK_DGRAM messages via a unique cgroup id, then we can alter the invocation ID to be generated as hash from that rather than entirely randomly. This way we can derive the invocation race-freely from the messages.
2016-03-15basic/log: remove unused return valueZbigniew Jędrzejewski-Szmek
2016-02-23tree-wide: minor formatting inconsistency cleanupsVito Caputo
2016-02-10tree-wide: remove Emacs lines from all filesDaniel Mack
This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.
2016-01-23journald: allow additional payload in server_driver_messageZbigniew Jędrzejewski-Szmek
The code to format the iovec is shared with log.c. All call sites to server_driver_message are changed to include the additional "MESSAGE=" part, but the new functionality is not used and change in functionality is not expected. iovec is preallocated, so the maximum number of messages is limited. In server_driver_message N_IOVEC_PAYLOAD_FIELDS is currently set to 1. New code is not oom safe, it will fail if memory cannot be allocated. This will be fixed in subsequent commit.
2015-10-24util-lib: split our string related calls from util.[ch] into its own file ↵Lennart Poettering
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.
2015-09-30log: move log_invalid_utf8() to log.hLennart Poettering
Also, make sure it follows the same scheme as log_syntax() does in its behaviour.
2015-06-11build-sys: split internal basic/ library from shared/Kay Sievers
basic/ can be used by everything cannot use anything outside of basic/ libsystemd/ can use basic/ cannot use shared/ shared/ can use libsystemd/