muselog

Introduce

Linux only. C99/C++ library. Simple client for syslog-ng. Easy to write flexible and strong config because for syslog-ng. Wrapper for syslog api. Four api contain.

Quick start

$ [dnf] or [yum] install syslog-ng.x86_64
$ cp conf.d/muse.conf /etc/syslog-ng/conf.d
$ service syslog-ng stop
$ service syslog-ng start
$ make [lib] or [example]

About syslog-ng

Opening muse.conf. You can see this code.

template t_muse {
	template("${S_DATE} musefs ${PROGRAM}[${PID}]: [${LEVEL}] ${MSG}\n"); template_escape(no);
};

Template is the place you define your message format.

I use the next format because it can be opened via vim and run filetype=messages to see more color.

[date] [name] [program[pid]]: [message]

For more detail. Click here for opening syslog-ng guide.

API

Just have four api.

bool log_start(Muselog *log, const char *logname, int facility);
bool flog(Muselog *log, int level, const char *fmt, ...);
bool vlog(Muselog *log, int level, const char *fmt, va_list ap);
bool log_move(Muselog *log, const char *save, int size);

Upon successful completion, four api will return true. Otherwise, the functions shall return false and set errno to indicate the error.

log_start

Two previous params is easy to understand. logname normally save under /var/log. facility argument is used to specify what type of program is logging the message. This lib use LOCAL 1~7 to save user-define log.

At muse.conf, you can see this code.

destination d_muse	{ file("/var/log/muse" template(t_muse)); };
filter 		f_muse  { facility(local1); };

local1 facility save message at /var/log/muse. So, it means, one facility bind to one file and just seven facility you can use.

flog and vlog

flog and vlog is thread-safe, because of syslog-ng. And level defined at muselog.h.

log_move

No thread-safe. Move your log to the path you want to save and truncate the old log. If you don't want to truncate the old file, put size = -1.

Last

Hope you enjoy!

museless/muselog