From e7bf4354b9914aa41bd5b7e1fa95095bb77ba4c4 Mon Sep 17 00:00:00 2001 From: Vadim Yanitskiy Date: Wed, 9 Sep 2020 03:36:48 +0700 Subject: logging: introduce 'systemd-journal' target This change implements 'systemd-journal' logging target, that is similar to the existing 'syslog' target. The key difference is that 'systemd-journal' allows us to offload rendering of the meta information, such as location (file name, line number), subsystem, and logging level, to systemd. Moreover, we can attach arbitrary, user-specific fields [1] to the logging messages, so they can be used for advanced log filtering (e.g. by IMSI/TMSI/TLLI): $ journalctl OSMO_SUBSYS=DMSC -f Since we don't want to make libsystemd a required dependency, this feature is optional, and needs to be enabled at build-time: $ ./configure --enable-systemd-logging The new logging target can be configured in the same way as any other one - via the VTY interface, or using the configuration file: log systemd-journal [raw] logging level set-all notice logging filter all 1 Two logging handlers are available: generic and raw. The first one behaves similarly to both 'syslog' and 'stderr', i.e. all the meta information is rendered by libosmocore itself, and then passed to systemd together with the logging message. The later is more like the 'gsmtap' target, so all available meta information is handed over to systemd in form of fields [1]: - CODE_FILE / CODE_LINE - location info, - PRIORITY - syslog-compatible logging level, - OSMO_SUBSYS - Osmocom-specific sub-system (e.g. DMSC), - OSMO_SUBSYS_HEX - same as OSMO_SUBSYS, but encoded in hex, - MESSAGE - the logging message itself, and then can be rendered in any supported format (e.g. JSON). More details about the API can be found in [2]. [1] https://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html [2] https://www.freedesktop.org/software/systemd/man/sd-journal.html Change-Id: I609f5cf438e6ad9038d8fc95f00add6aac29fb23 --- include/osmocom/core/logging.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/osmocom') diff --git a/include/osmocom/core/logging.h b/include/osmocom/core/logging.h index 36ce941c..6d0d5a3a 100644 --- a/include/osmocom/core/logging.h +++ b/include/osmocom/core/logging.h @@ -244,6 +244,7 @@ enum log_target_type { LOG_TGT_TYPE_STDERR, /*!< stderr logging */ LOG_TGT_TYPE_STRRB, /*!< osmo_strrb-backed logging */ LOG_TGT_TYPE_GSMTAP, /*!< GSMTAP network logging */ + LOG_TGT_TYPE_SYSTEMD, /*!< systemd journal logging */ }; /*! Whether/how to log the source filename (and line number). */ @@ -311,6 +312,10 @@ struct log_target { const char *ident; const char *hostname; } tgt_gsmtap; + + struct { + bool raw; + } sd_journal; }; /*! call-back function to be called when the logging framework @@ -392,6 +397,8 @@ struct log_target *log_target_create_gsmtap(const char *host, uint16_t port, const char *ident, bool ofd_wq_mode, bool add_sink); +struct log_target *log_target_create_systemd(bool raw); +void log_target_systemd_set_raw(struct log_target *target, bool raw); int log_target_file_reopen(struct log_target *tgt); int log_targets_reopen(void); -- cgit v1.2.3