.\" Copyright (c) 2018 Mariusz Zaborski <oshogbo@FreeBSD.org>
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
.Dd January 27, 2018
.Dt CAP_SYSLOG 3
.Os
.Sh NAME
.Nm cap_syslog
.Nm cap_vsyslog
.Nm cap_openlog
.Nm cap_closelog
.Nm cap_setlogmask
.Nd "library for syslog in capability mode"
.Sh LIBRARY
.Lb libcap_syslog
.Sh SYNOPSIS
.In libcasper.h
.In casper/cap_syslog.h
.Ft void
.Fn cap_syslog "cap_channel_t *chan" "int pri" "const char *fmt" "..."
.Ft void
.Fn cap_vsyslog "cap_channel_t *chan" "int priority" "const char *fmt" "va_list ap"
.Ft void
.Fn cap_openlog "cap_channel_t *chan" "const char *ident" "int logopt" "int facility"
.Ft void
.Fn cap_closelog "cap_channel_t *chan"
.Ft int
.Fn cap_setlogmask "cap_channel_t *chan" "int maskpri"
.Sh DESCRIPTION
The functions
.Fn cap_syslog
.Fn cap_vsyslog
.Fn cap_openlog
.Fn cap_closelog
.Fn cap_setlogmask
are respectively equivalent to
.Xr syslog 3 ,
.Xr vsyslog 3 ,
.Xr openlog 3 ,
.Xr closelog 3 ,
.Xr setlogmask 3
except that the connection to the
.Nm system.syslog
service needs to be provided.
.Sh EXAMPLES
The following example first opens a capability to casper and then uses this
capability to create the
.Nm system.syslog
casper service to log messages.
.Bd -literal
cap_channel_t *capcas, *capsyslog;

/* Open capability to Casper. */
capcas = cap_init();
if (capcas == NULL)
	err(1, "Unable to contact Casper");

/* Enter capability mode sandbox. */
if (cap_enter() < 0 && errno != ENOSYS)
	err(1, "Unable to enter capability mode");

/* Use Casper capability to create capability to the system.syslog service. */
capsyslog = cap_service_open(capcas, "system.syslog");
if (capsyslog == NULL)
	err(1, "Unable to open system.syslog service");

/* Close Casper capability, we don't need it anymore. */
cap_close(capcas);

/* Let's log something. */
cap_syslog(capsyslog, LOG_NOTICE, "System logs from capability mode.");
.Ed
.Sh SEE ALSO
.Xr cap_enter 2 ,
.Xr closelog 3 ,
.Xr err 3 ,
.Xr openlog 3 ,
.Xr setlogmask 3
.Xr syslog 3 ,
.Xr vsyslog 3 ,
.Xr capsicum 4 ,
.Xr nv 9
.Sh AUTHORS
.An Mariusz Zaborski Aq Mt oshogbo@FreeBSD.org