gwcrontab.c File Reference

Handlers for cron-like data for scheduling jobs. More...

#include "gwcrontab.h"
#include "daemon.h"
#include "log.h"
#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <syslog.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <time.h>
#include <assert.h>

Defines
#define	debug(prg)   { if (debug_flag) { prg } }
	Run debug code if debugging is enabled.
Functions
gwcron_job *	get_first_job (gwcron_job *queue, int time)
	Return the first job in the queue due to be executed from the current time onwards.
int	append_job (gwcron_job **queue, int time, const char *cmd)
	Add a job into a job queue, inserting it into the linked list at the right chronological point.
void	flush_jobs (gwcron_job *queue)
	Clear up and free all the entries in a job queue.
void	dump_jobs (gwcron_job *job)
	Dump a job queue to standard out for debug purposes.
int	read_crontab ()
	Read in the jobs file and parse it into a chronologically ordered single linked list.
int	read_minutes (struct timeval *tv)
	Calculate the number of minutes into the day the given time is.
int	read_day (struct timeval *tv)
	Determine the day of the year we are on.
Variables
const int	debug_flag = 0
	Control whether debug code is run.
const char *	etc_directory = ETCDIR
	Directory where config files are stored.
const char *	crontab_file = "/gwcrontab"
	File name of config file containing jobs list.
gwcron_job *	job_queue = NULL
	Pointer to chronologically ordered linked list of daily jobs.

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Detailed Description

Handlers for cron-like data for scheduling jobs.

Copyright (C) 2004 Alistair Riddoch, The University of Southampton

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Function Documentation

int append_job (  gwcron_job **  queue, int  time, const char *  cmd )

Add a job into a job queue, inserting it into the linked list at the right chronological point. Parameters: queue  pointer to pointer to start of the job queue. time  in minutes when the job should be run each day. cmd  string of the commandline to be run to do the job. Returns: one if an error occured, zero otherwise.

gwcron_job* get_first_job (  gwcron_job *  queue, int  time )

Return the first job in the queue due to be executed from the current time onwards. This should be called whenever the config file has been read in. Parameters: queue  pointer to the start of the job queue. time  the current time of day in minutes. Returns: a pointer to the next due job, or NULL is no job is due for the rest of the day.

int read_day (  struct timeval *  tv  )

Determine the day of the year we are on. Used to make sure we have got to the next day when there are no jobs left today. Parameters: tv  pointer to time structure with the unix time. Returns: the day of the year.

int read_minutes (  struct timeval *  tv  )

Calculate the number of minutes into the day the given time is. Parameters: tv  pointer to time structure with the unix time. Returns: the time in minutes since midnight.

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Variable Documentation

const int debug_flag = 0 [static]

Control whether debug code is run. Set to non-zero if debug code should be run.

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