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/*
	WARNING: This file was generated by dkct.
	Changes you make here will be lost if dkct is run again!
	You should modify the original source and run dkct on it.
	Original source: dk4dmt.ctr
*/

/*
Copyright (C) 2016-2017, Dirk Krause

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above opyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.
* Neither the name of the author nor the names of contributors may be used
  to endorse or promote products derived from this software without specific
  prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
*/

#ifndef DK4DMT_H_INCLUDED
/** Avoid multiple inclusions. */
#define DK4DMT_H_INCLUDED 1


#line 8 "dk4dmt.ctr"

/**	@file	dk4dmt.h	Daemon tools.

The functions in this module can be used in standing daemons.

In the original process, call the
dk4dmt_parent_before_fork() function to close all file descriptors
above 2, reset all signal handlers to defaults, unblock all signals
and check whether a PID file already exists.
If you plan to give up root privileges in the child processes
(use setgid() and setuid() to change effective user and group),
do not use /var/run/<i>program</i>.pid as PID file name, better
use /var/run/<i>program</i>/<i>program</i>.pid instead and make
sure to set ownership and group on /var/run/<i>program</i>
to the unprivileged user and group used by the child process.
User and group need write permission to the directory, so the unprivileged
child process can remove the PID file when exiting.

In the intermediate process after the first fork call
dk4dmt_intermediate_before_fork(). Among other things this function
completely decouples the process from the terminal.

In the final process (after forking again) call
dk4dmt_daemon_after_fork()
to set up things before starting service. This function creates the PID
file, connects file descriptors 0, 1 and 2 to /dev/null, resets
the umask and changes into the / directory.

After finishing service call
dk4dmt_daemon_end() before exiting. This function removes the PID
file.
*/

#ifdef __cplusplus
extern "C" {
#endif

/**	Activities in parent process before calling fork().
	* Close all file descriptors above 2.
	* Reset all signal actions to default handlers.
	* Unblock all signals.
	* Check whether PID file already exists.
	Use this function to check whether the initial process
	can run fork().
	@param	prgname		Program name.
	@param	pidfilename	PID file name.
	@param	logstderr	Flag: Logging to stderr allowed.
	@param	slf		Syslog feature.
	@return	1 on success (can call fork), 0 on error (abort).
*/
int
dk4dmt_parent_before_fork(
  const char *prgname, const char *pidfilename, int logstderr, int slf
);


/**	Activities in first child before calling fork() again.
	* Decouple completely from terminal.
	Use this function to check whether the first child process
	can run fork() again.
	@param	prgname	Program name.
	@param	slf	Syslog feature.
	@return	1 on success (can call fork), 0 on error (abort).
*/
int
dk4dmt_intermediate_before_fork(const char *prgname, int slf);

/**	Activities in final daemon process.
	* Create PID file.
	* Connect file descriptors 0, 1 and 2 to /dev/null.
	* Reset umask.
	* Change into / directory.
	@param	prgname		Program name.
	@param	pidfilename	File name for PID file.
	@param	slf		Syslog feature.
	@return	1 on success, 0 on error.
*/
int
dk4dmt_daemon_after_fork(const char *prgname, const char *pidfilename, int slf);

/**	End of daemon, remove PID file.
	@param	prgname		Program name.
	@param	pidfilename	PID file name.
	@param	slf		Syslog feature.
*/
void
dk4dmt_daemon_end(const char *prgname, const char *pidfilename, int slf);

#ifdef __cplusplus
}
#endif


#endif