greatly simplify it to report idle seconds to a script

README

@@ -1,4 +1,24 @@
 afkcron
 =======
-afkcron reads a configuration which specifies programs to launch after n seconds of afk time. 
+afkcron simply reports the idle time of the X11 server to a shell script.
-Once the user is afk for those seconds, it then starts the program. 
+
+Originally, it was reading config files and also handling the return of the
+user by decreasing priority of launched processes or killing them etc.
+
+Now I considered it's best for it to be rather stupid and delegate this 
+to a shell script for example. 
+
+Launching afkcron
+=================
+afkcron [path to script] [how often idle time should be polled, in seconds]
+
+Example: afkcron script.sh 30 
+
+Shellscript
+===========
+First argument: "active" (if idle time has stopped), "idle": When idling
+Second argument: the number of seconds X11 is idling.
+
+Dependencies
+============
+libX11, libXss. Should be a given.

afkcron.c

@@ -1,7 +1,7 @@
 /*
- * afkcron launches a program depending on the time the user is not using his machine
+ * afkcron launches a script depending on the time the user is not using his machine
 *
- * Copyright (c) 2014-2017 Albert S. <launchutils at quitesimple dot org>
+ * Copyright (c) 2014-2018 Albert S. <launchutils at quitesimple dot org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -19,137 +19,17 @@
 #define _XOPEN_SOURCE 700
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
 #include <signal.h>
 #include <stdbool.h>
-#include <stdarg.h>
-#include <time.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <sys/time.h>
-#include <sys/resource.h>
 #include <X11/Xlib.h>
 #include <X11/extensions/scrnsaver.h>
-#include <ctype.h>
-
-#define CONFIG_DEFAULT_PATH "/etc/afkcron"
-#define CONFIG_DELIMER ':'
-
-//return actions flags
-#define FLAG_RETURN_KILL (1 << 0)
-#define FLAG_RETURN_PRIO (1 << 1)
-#define FLAG_RETURN_STOP (1 << 2)
-#define FLAG_RETURN_STAY (1 << 3)
-#define FLAG_RETURN_TERM (1 << 4)
-#define FLAG_RETURN_TERMKILL (FLAG_RETURN_TERM | FLAG_RETURN_KILL)
-//general flags
-#define FLAG_SINGLE_SHOT (1 << 0) // fire only once during program lifetime
-
-//consider merging return action flags and general flags
-struct entry 
-{
-	pid_t pid; // 0 = can be ran, -1 single shot entry which finished, pid > 0 = currently running
-	bool stopped;
-	const char *path;
-	const char *args;
-	int comeback_action; //What to do, when the user returns, starts using the computer again?
-	int idle_seconds;
-	int flags;
-	struct entry *next;
-};
-
-FILE *logfp = NULL;
-
-struct entry *head_entry = NULL; 
-struct entry *tail_entry = NULL;
-
-void *xmalloc(size_t n)
-{
-	char *tmp = malloc(n);
-	if(tmp == NULL)
-	{
-		perror("malloc");
-		exit(EXIT_FAILURE);
-	}
-	return tmp;
-}
-
-void *xstrdup(const char *str)
-{
-	char *result = strdup(str);
-	if(result == NULL)
-	{
-		perror("strdup");
-		exit(EXIT_FAILURE);
-	}
-	return result;
-}
 
 bool strempty(const char *str)
 {
 	return str == NULL || *str == '\0';
 }
 
-int strcnt(const char *str, const char c)
-{
-	int result = 0;
-	while(*str)
-		if(*str++ == c) ++result;
-	return result; 
-}
-
-int split_string(char ***out, const char *str, char delim)
-{
-	int current = 0;
-	int items = strcnt(str, delim) + 1;
-	*out = xmalloc(items * sizeof(char *));
-	char *temp = xstrdup(str);
-	char *portion = temp;
-	while(*temp)
-	{
-		if(*temp == delim) 
-		{
-			*temp=0;
-			(*out)[current] = portion;
-			++current;
-			portion = temp+1;
-		}
-		++temp;
-	}
-	(*out)[current] = portion;
-	return ++current;
-}
-
-const char **create_execv_args(const char *name, const char *str, char delim)
-{
-	if(strempty(name))
-		return NULL;
-	const char **result = NULL;
-	if(strempty(str))
-	{
-		result = xmalloc(2 * sizeof(char *));
-		result[0] = name;
-		result[1] = NULL;
-	}
-	else
-	{
-		int items=2;
-		char **args = NULL;
-		int n_args = split_string(&args, str, delim);
-		items += n_args;
-		result = xmalloc(items * sizeof(char *)); 
-		result[0] = name;
-		for(int i=0; i < n_args; i++)
-			result[i+1] = args[i];
-		result[items-1] = NULL;
-	}
-	return result;
-
-}
-
-
-
 void print_err_and_exit(const char *s)
 {
 	fputs(s, stderr);
@@ -163,335 +43,116 @@ void perror_and_exit(const char *s)
 }
 
 
-void logit(const char *format, ...)
-{
-	if(logfp != NULL)
-	{
-		va_list args;
-		va_start(args, format);
-		time_t now = time(0);
-		char *timestr = ctime(&now);
-		size_t len = strlen(timestr);
-		if(timestr[len-1] == '\n')
-		{
-			timestr[len-1] = 0;
-		}
-		fprintf(logfp, "%s: ", timestr);
-		vfprintf(logfp, format, args);
-		fflush(logfp);
-		va_end(args);
-	}
 
-}
 
 int get_idle_seconds(Display *display)
 {
 	XScreenSaverInfo info;
 	if(XScreenSaverQueryInfo(display, DefaultRootWindow(display), &info) == 0)
+	{
 		return -1; 
+	}
 	return info.idle / 1000; 
 }
 
-void add_entry(struct entry *e)
-{
-	if(head_entry == NULL)
-		head_entry = e;
-	if(tail_entry != NULL)
-		tail_entry->next = e;
-	tail_entry = e;
-}
-
-
-int comeback_action_from_string(const char *str)
-{
-		int result = 0;
-		if(! strempty(str))
-		{
-			if(strcmp(str, "kill") == 0)
-				result |= FLAG_RETURN_KILL;
-			else if(strcmp(str, "stop") == 0)
-				result |= FLAG_RETURN_STOP;
-			else if(strcmp(str, "prio") == 0)
-				result |= FLAG_RETURN_PRIO;
-			else if(strcmp(str, "term") == 0)
-				result |= FLAG_RETURN_TERM;
-			else if(strcmp(str, "termkill") == 0)
-				result |= FLAG_RETURN_TERMKILL;
-			else
-				result |= FLAG_RETURN_STAY;
-		}
-		return result;
-}
-
-int flags_from_string(const char *str)
-{
-	int result = 0;
-	if(strstr(str, "oneshot"))
-		result |= FLAG_SINGLE_SHOT;
-	return result;
-}
-//TODO: check integer overflow
-int secs_from_string(char *unitstr)
-{
-	if(unitstr == NULL) 
-		return -1;
-	size_t len = strlen(unitstr);
-	char unit = unitstr[len-1];
-	if(! isdigit(unit))
-		unitstr[len-1] = '\0';
-	
-	int secs = atoi(unitstr);
-	if(secs < 0)
-		return -1;
-	
-	switch(unit)
-	{
-			case 'd':
-				secs *= 24;
-			case 'h':
-				secs *= 60;
-			case 'm':
-				secs *= 60;
-	}
-	
-	return secs;
-}
-
-struct entry *entry_from_line(const char *line)
-{
-	char *l = xstrdup(line);
-	
-	char **fields = NULL;
-	int n_fields = split_string(&fields, l, CONFIG_DELIMER);
-	if(n_fields < 5)
-		return NULL;
-
-	struct entry *result = xmalloc(sizeof(struct entry));
-	result->path = fields[0];
-	result->args = fields[1];
-	result->comeback_action = comeback_action_from_string(fields[2]);
-	result->idle_seconds = secs_from_string(fields[3]);
-	result->flags = flags_from_string(fields[4]);
-	return result;
-
-}
-
-
-static inline bool check_entry(struct entry *e)
-{
-	return ( ! strempty(e->path) ) && ( e->idle_seconds > 0 ) && ( e->comeback_action > 0 ); 
-}
-
-void read_config(const char *configfile)
-{
-	FILE *fp = fopen(configfile, "r");
-	if(fp == NULL)
-	{
-		perror_and_exit("fopen");
-	}	
-	char *line;
-	size_t n = 0;
-	ssize_t r;
-	while((r = getline(&line, &n, fp)) != -1 )
-	{
-		if(line[r-1] == '\n') 
-			line[r-1] = '\0';
-	
-		struct entry *e = entry_from_line(line);
-		if(e == NULL)
-			print_err_and_exit("error reading from file");
-				
-		if(! check_entry(e))
-			print_err_and_exit("Invalid values for entry");
-		
-		add_entry(e);
-		
-		
-	}
-	
-	if(ferror(fp))
-		perror_and_exit("error reading from config file");
-	fclose(fp);
-}
-
-void handle_comeback()
-{
-	for(struct entry *current = head_entry; current != NULL; current = current->next)
-	{
-		if(current->pid > 0)
-		{
-			int comeback_action = current->comeback_action;
-			bool wants_term = (comeback_action & FLAG_RETURN_TERM) == FLAG_RETURN_TERM;	
-			
-			if(wants_term)
-			{
-				logit("Terminating %z\n", current->pid);
-				kill(current->pid, SIGTERM);
-			}
-		
-			if(comeback_action & FLAG_RETURN_KILL)
-			{
-				if(wants_term)
-					while(sleep(2));
-				if(kill(current->pid, SIGKILL) == 0)
-				{
-					logit("Killed %z\n", current->pid);
-					current->pid = 0;
-				}
-				//TODO: and if fail?...
-			}
-			if(comeback_action & FLAG_RETURN_STOP)
-			{
-				if(kill(current->pid, SIGSTOP) == 0)
-				{
-					logit("Stopped %z\n", current->pid);
-					current->stopped = true;
-					//TODO: ...
-				}
-			}
-			
-			if(comeback_action & FLAG_RETURN_PRIO)
-			{
-				logit("Lowering priority for %z\n", current->pid);
-				setpriority(PRIO_PROCESS, current->pid, 19);
-				//TODO: IO prio?
-			}
-		}
-		
-	}
-}
-
-void handle_finished_pid(pid_t pid)
-{
-	for(struct entry *current = head_entry; current != NULL; current = current->next)
-	{
-		if(current->pid == pid)
-		{
-			if( (current->flags & FLAG_SINGLE_SHOT) )
-			{
-				current->pid = -1;
-			}
-			else
-				current->pid = 0;
-		}
-	}
-}
-
-
 void child_handler(int signum, siginfo_t *info, void *context)
 {
 	if(signum != SIGCHLD) 
+	{
 		return;
-		
+	}
-	pid_t pid = info->si_pid;
-	//TODO
 	int status;
-	int x = waitpid(pid, &status, WNOHANG);
+	int ret = waitpid(info->si_pid, &status, WNOHANG);
-	if(x == -1)
+	if(ret == -1)
-		print_err_and_exit("waitpid failed");
+	{
-	handle_finished_pid(pid);
+		perror_and_exit("waitpid failed");
-	
+	}
-	
+	if(status == EXIT_FAILURE)
+	{
+		print_err_and_exit("script did not succeed, exiting");
+	}
+
 }
+
 void set_signals()
 {
 	struct sigaction action;
 	action.sa_flags = SA_NOCLDSTOP | SA_SIGINFO;
 	action.sa_sigaction = &child_handler;
 	if(sigaction(SIGCHLD, &action, NULL) == -1)
-		print_err_and_exit("sigaction failed");
+	{
+		perror_and_exit("sigaction failed");
+	}
 }
 
-
+void run_script(const char *path, const char *type, int sleepseconds)
-bool run_entry(struct entry *e)
 {
-	const char **args = create_execv_args(e->path, e->args, ' ');
 	pid_t child = fork();
 	if(child == 0)
 	{
-		logit("Starting execution of %s\n", e->path);
+		char sleepstr[20];
-		execv(e->path, (char * const *)args);
+		snprintf(sleepstr, sizeof(sleepstr), "%i", sleepseconds);
-		fclose(logfp);	
+		const char *args[4];
-	}
+		args[0] = path;
-	else if(child > 0)
+		args[1] = type;
-		e->pid = child;
+		args[2] = sleepstr;
-	return child != -1;
+		args[3] = NULL;
-}
+		execv(path, (char * const *)args);
+		perror_and_exit("failed launching script");
 
-void run_entries(int idle_seconds)
+	}
-{
+	if(child == -1)
-	for(struct entry *e = head_entry; e != NULL; e = e->next)
 	{
-		if(e->idle_seconds > idle_seconds) 
+		perror_and_exit("fork failed");
-			continue; 
-		if(e->pid == 0)
-			run_entry(e);
-		if(e->pid > 0 && e->stopped)
-		{
-			logit("Continuing %z\n", e->pid);
-			if(kill(e->pid, SIGCONT) == 0)
-				e->stopped = false;
-		
-		}
-		
 	}
 }
 
-
-
 int main(int argc, char *argv[])
 {
+	if(argc < 3)
+	{
+		printf("Usage: afkcron script.sh interval\n");
+		exit(EXIT_FAILURE);
+	}
+	
+	const char *scriptpath = argv[1];
+	unsigned int interval = strtol(argv[2], NULL, 10);
+	
 	Display *display = XOpenDisplay(NULL);
 	if(display == NULL)
+	{
 		print_err_and_exit("Couldn't open DISPLAY");
-
+	}
 	
 	int event_base, error_base;
 
 	if (! XScreenSaverQueryExtension(display, &event_base, &error_base)) 
+	{
 		print_err_and_exit("No XScreenSaver Extension available on this display");
-		
+	}
 	set_signals();
 	
 
 
-
-	int option;
-	while((option = getopt(argc, argv, "c:l:")) != -1)
-	{
-		switch(option)
-		{
-			case 'c':
-				read_config(optarg);
-				break;
-			case 'l':
-				logfp = fopen(optarg, "a");
-				if(logfp == NULL)
-				{
-					print_err_and_exit("Error opening log file");
-				}
-				break;
-
-		}
-	}
-	if(head_entry == NULL)
-	{
-		read_config(CONFIG_DEFAULT_PATH); 
-	}
 	int previous_seconds = 0;
 	while(1)
 	{
 		int idle_seconds = get_idle_seconds(display);
 		if(idle_seconds == -1)
+		{
 			print_err_and_exit("X11 Screen Saver Extension not supported?");
-
+		}
+		
 		if(previous_seconds > idle_seconds)
-				handle_comeback();
+		{
+			run_script(scriptpath, "active", idle_seconds);
+		}
 		else
-				run_entries(idle_seconds);
+		{
-			
+			run_script(scriptpath, "idle", idle_seconds);
+		}
 		previous_seconds = idle_seconds;
-		while(sleep(10)); // Well this sleep approach is suboptimal, do it with events somehow if possible.
+		while(sleep(interval));
 	}
 
 }

afkcron_config.conf

@@ -1 +0,0 @@
-/bin/touch:/tmp/works:kill:5:oneshot

script.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+echo "State is: $1. Been idling for $2"