#include <stdio.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <modapi_def.h>
#include <modapi.h>
#include <misc.h>
#include <tlmpdia.h>
#include <tlmplib.h>
#include "monitortasks.m"

static HELP_FILE help_choice ("monitortasks","killchoice");

/*
	Read the first line of a file
	Return -1 if any error.
*/
static int process_readfile (const char *path, char *buf, int sizebuf)
{
	int ret = -1;
	// No error message signaled as "path" is a file under /proc/pid
	// and the process may vanish while we are reading it.
	FILE *fin = fopen (path,"r");
	if (fin != NULL){
		if (fgets (buf,sizebuf-1,fin)!=NULL){
			ret = 0;
		}
		fclose (fin);
	}
	return ret;	
}

struct PS_PROC {
	char cmdline[256], user[10], cmd[40], state, ttyc[4];
	int uid, pid, ppid, pgrp, session, tty, tpgid, utime, stime,
	cutime, cstime, counter, priority, start_time, signal, blocked,
	sigignore, sigcatch;
	unsigned int flags, min_flt, cmin_flt, maj_flt, cmaj_flt, timeout,
	it_real_value, vsize, rss, rss_rlim, start_code, end_code,
	start_stack, kstk_esp, kstk_eip, wchan;
};
/*
	Read the file /proc/pid/stat into the struct PS_PROC
	Return -1 if any error.
*/

static int process_readppid (int pid)
{
	int ret = -1;
	char tmppath[PATH_MAX];
	sprintf (tmppath,"/proc/%d/stat",pid);
	char buf[PATH_MAX];
	if (process_readfile (tmppath,buf,sizeof(buf))!=-1){		
		PS_PROC psp;
		sscanf(buf, "%d %s %c %d %d %d %d %d %u %u "
			"%u %u %u %d %d %d %d %d %d %u "
			"%u %d %u %u %u %u %u %u %u %u %u "
			"%u %u %u %u\n",
			&psp.pid, psp.cmd, &psp.state, &psp.ppid,
			&psp.pgrp, &psp.session, &psp.tty, &psp.tpgid,
			&psp.flags, &psp.min_flt, &psp.cmin_flt,
			&psp.maj_flt, &psp.cmaj_flt,
			&psp.utime, &psp.stime, &psp.cutime, &psp.cstime,
			&psp.counter, &psp.priority, &psp.timeout,
			&psp.it_real_value, &psp.start_time,
			&psp.vsize, &psp.rss, &psp.rss_rlim,
			&psp.start_code, &psp.end_code, &psp.start_stack,
			&psp.kstk_esp, &psp.kstk_eip,
			&psp.signal, &psp.blocked, &psp.sigignore, &psp.sigcatch,
			&psp.wchan);
		ret = psp.ppid;
	}
	return ret;
}

/*
	Locate the first process child of a given process
*/
static int killchoice_findchild (int pid)
{
	pid_t ret = (pid_t)-1;
	SSTRINGS lst;
	int n = dir_getlist ("/proc",lst);
	for (int i=0; i<n; i++){
		const char *dirpid = lst.getitem(i)->get();
		int child = atoi(dirpid);
		if (pid != 0){
			int parent = process_readppid (child);
			if (parent == pid){
				ret = child;
				break;
			}
		}
	}
	return ret;
}

<mod>
int main (int argc, char *argv[])
{
	char bdict[30];
	sprintf (bdict,"monitortasks-msg-%s",PACKAGE_REV);
	const char *packages[]={bdict,NULL};
	<call tlmpprogram>(argc, argv,packages);
		<f usage>
			xconf_notice (MSG_U(N_CHOICEUSAGE,"killchoice program-name pid [ args ]"));
		</f>
		<f main>
			int ret = -1;
			if (argc == 2){
				pid_t parent = atoi(argv[1]);
				pid_t pid = killchoice_findchild (parent);
				if (pid != (pid_t)-1){
					DIALOG dia;
					dia.settype (DIATYPE_POPUP);
					char opt=0;
					dia.newf_radio ("",opt,0,MSG_U(I_KILLRUN
						,"Terminate the process and start a new one"));
					dia.newf_radio ("",opt,1,MSG_U(I_RUNEW
						,"Start a new one"));
					dia.newf_radio ("",opt,2,MSG_U(I_KILL
						,"Terminate the process"));
					SSTRING intro;
					intro.setfromf (MSG_U(I_ALREADY
						,"The program %s (process id %u) is already running\n"
						 "It is unusual to start several instances of this program\n"
						 "Pick the appropriate option"),argv[0],pid);
					int nof=0;
					if (dia.edit (MSG_U(T_ALREADY,"Process already running")
						,intro.get()

						,help_choice
						,nof)==MENU_ACCEPT){
						if (opt == 0 || opt == 2){
							kill (pid,SIGTERM);
							// Wait until it it dead
							for (int i=0; i<5; i++){
								if (kill(pid,0)!=-1){
									sleep(1);
								}else{
									break;
								}
							}
							if (kill(pid,0)!=-1) kill (pid,SIGKILL);
						}
						if (opt == 0 || opt == 1){
							exit (0);
						}else{
							exit (1);
						}
					}
				}else{
					xconf_error (MSG_U(E_NOCHILD,"No child for process %u!!!")
						,parent);
				}
			}else{
				usage();
			}
			return ret;
		</f>
	</call>
	return -1;
}
</mod>