serval-dna/log_prolog.h

/*
Serval DNA log prolog
Copyright (C) 2017 Flinders University
 
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
 
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*/

#ifndef __SERVAL_DNA__LOG_PROLOG_H
#define __SERVAL_DNA__LOG_PROLOG_H

#include "trigger.h"

/* Whenever a log output starts a new log, such as opening the console for the
 * first time or rotating to a new log file, or even at a regular interval, it
 * emits a "prolog" that starts with the current date/time, then a series of
 * log messages generated by invoking all the log_prolog triggers.
 *
 * The log_prolog trigger functions call the standard logging API to produce
 * their output, but the logging system uses an internal trick to ensure that
 * the their messages only go to the log output that invoked them, so for
 * example, when a log file rotates, the prolog only gets written into the new
 * file, and not into the console log as well.
 */
DECLARE_TRIGGER(log_prolog);

struct log_output_iterator;

void serval_log_print_prolog(struct log_output_iterator *it);

#endif // __SERVAL_DNA__LOG_PROLOG_H
Rewrite logging system Rename the logging primitive functions and utility functions, prefixing all with 'serval_log', eg: logMessage() -> serval_logf() etc. Add an XPRINTF xhexdump() function and use it to implement the serval_log_hexdump() utility, renamed from dump(). Add macros WHY_dump(), WARN_dump(), HINT_dump() and DEBUG_dump(), and use them everywhere. Remove the 'log.console.dump_config' and 'log.file.dump_config' configuration options; configuration is now dumped in every log prolog. The logging system now constructs the log prolog by invoking the new 'log_prolog' trigger, so that it no longer depends on the version string and configuration system. Any system that wants to present a message in the log prolog can define its own trigger, which calls standard log primitives to print the message. Split the logging system into a front-end (log.c) that provides the logging primitives and is independent of the configuration system, and a set of back-end "outputters" (log_output_console.c, log_output_file.c, log_output_android.c) that may depend on the configuration system and are decoupled from the front-end using the 'logoutput' link section. These log outputters are explicitly linked into executables by the Makefile rules, but could also be linked in using USE_FEATURE(). The USE_FEATURE() calls have _not_ been added to servald_features.c, so that different daemon executables can be built with the same feature set but different log outputs. 2017-11-29 13:34:54 +00:00			`/*`
			`Serval DNA log prolog`
			`Copyright (C) 2017 Flinders University`

			`This program is free software; you can redistribute it and/or`
			`modify it under the terms of the GNU General Public License`
			`as published by the Free Software Foundation; either version 2`
			`of the License, or (at your option) any later version.`

			`This program is distributed in the hope that it will be useful,`
			`but WITHOUT ANY WARRANTY; without even the implied warranty of`
			`MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the`
			`GNU General Public License for more details.`

			`You should have received a copy of the GNU General Public License`
			`along with this program; if not, write to the Free Software`
			`Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.`
			`*/`

			`#ifndef __SERVAL_DNA__LOG_PROLOG_H`
			`#define __SERVAL_DNA__LOG_PROLOG_H`

			`#include "trigger.h"`

			`/* Whenever a log output starts a new log, such as opening the console for the`
			`* first time or rotating to a new log file, or even at a regular interval, it`
			`* emits a "prolog" that starts with the current date/time, then a series of`
			`* log messages generated by invoking all the log_prolog triggers.`
			`*`
			`* The log_prolog trigger functions call the standard logging API to produce`
			`* their output, but the logging system uses an internal trick to ensure that`
			`* the their messages only go to the log output that invoked them, so for`
			`* example, when a log file rotates, the prolog only gets written into the new`
			`* file, and not into the console log as well.`
			`*/`
			`DECLARE_TRIGGER(log_prolog);`

			`struct log_output_iterator;`

			`void serval_log_print_prolog(struct log_output_iterator *it);`

			`#endif // __SERVAL_DNA__LOG_PROLOG_H`