/* Verbal monitor system status.
 * $Id: vmon.c 1.2 Mon, 24 Mar 1997 12:25:37 -0500 dyfet $
 * Copyright (c) 1997 by Tycho Softworks.
 * For conditions on distribution and reuse see product license.
 *
 * Abstract:
 *	Monitor system status in background.  This service is normally
 *	started with the speech server.  It may also be ran as 'vstat'
 *	to perform immediate notification.
 */

#include <std/time.h>
#include <other/string.h>
#include <proc/process.h>
#include <other/config.h>
#include <net/stream.h>
#include <std/utmp.h>

/* For systems that use statfs! */

#ifdef	__linux__
#include <sys/vfs.h>
#define	__statfs__
#endif

typedef	struct	_MAILBOX
{
	struct	_MAILBOX	*next;
	time_t	update;
	ulong	size;
	char	name[0];
}	MAILBOX;

static	int	freq = 3600;
static	int	timer = 3600;
static	int	interval = 300;
static	int	iter;
static	int	orig_timer;
static	int	alert = 90;	/* warn on 90% full */
static	char	alertmsg[] = "emergency alert              emergency alert         \r\n"; 
static	char	**fs;
static	char	host[128] = "localhost";
static	int	mute[2] = {24, 0};

static	char	*vmailbox(MAILBOX *mbox)
{
	struct	stat	ino;
	static	char	buf[80];

	if(stat(mbox->name, &ino))
		return NULL;

	if(!ino.st_size)
	{
		mbox->size = 0;
		return NULL;
	}

	if(ino.st_size == mbox->size)
		return NULL;

	if(mbox->size == -1)
	{
		mbox->size = ino.st_size;
		return NULL;
	}

	mbox->size = ino.st_size;
	sprintf(buf, "User %s has new mail\n", mbox->name);
	return	buf;
}		
		
static	void	vmbox(MAILBOX *box, int port)
{
	STREAM	fp = NULL;
	char	*p;
	time_t	now;
	struct	tm	*dt;
	char	buf[128];
	
	time(&now);
	dt = localtime(&now);	
	if(dt->tm_hour > mute[0] || dt->tm_hour < mute[1])
		return;
	
	while(box)
	{
		p = vmailbox(box);
		if(!p)
		{
			box = box->next;
			continue;
		}
		if(!fp)
		{
			fp = opentcp(host, port);
			if(!fp)
				return;

			gettcp(buf, sizeof(buf) - 1, fp);
		}
		puttcp(p, fp);
		box = box->next;
	}
	if(fp)
		closetcp(fp);
}

static	int	vstat(int port)
{
	int	i = 0;
	char	*f;
	long	btotal = 0;
	long	bfree = 0;
	bool	failed = FALSE;
	STREAM	fp = NULL;
#ifdef	__statfs__
	struct	statfs	fnode;
#endif
	int	blocks, inodes;
	char	buf[128];
	int	newtimer = orig_timer;
	time_t	now;
	static	prior = -1;
	struct	tm	*dt;
	int	apm, hour;
	char	*apmstr[] = {" A M ", " P M "};
	int	fd;
	struct	utmp	*utmp, uptime;
	int	users = 0;
	int	utcnt = 0;

#ifdef	__statfs__
	while(fs[i])
	{
		if(!statfs(fs[i], &fnode)) 
		{
			btotal += fnode.f_blocks;
			bfree += fnode.f_bfree;
			blocks = 100 - (int)(fnode.f_ffree / (fnode.f_files / 100l));	
			inodes = 100 - (int)(fnode.f_bfree / (fnode.f_blocks / 100l));
			if((blocks < alert) && (inodes < alert))
			{
				++i;
				continue;
			}
		}
		else
		{
			inodes = 0;
			blocks = 0;
			failed = TRUE;
		}	
		if(!fp)
		{
			fp = opentcp(host, port);
			if(!fp)
			{
				newtimer = 300;
				break;
			}
			gettcp(buf, 128, fp);
			puttcp(alertmsg, fp);
		}

		if(blocks > alert)
			fprintf(fp, "File system %s is %d percent full.\r\n", fs[i], blocks);

		if(inodes > alert)
			fprintf(fp, "File system %s i-node table is %d percent full.\r\n", fs[i], inodes);

		if(failed)
			fprintf(fp, "File system %s is dismounted or failed\r\n", fs[i]);

		fflush(fp);
		newtimer = 60;
		++i;
	}
#endif
	
	if(fp)
		closetcp(fp);
	
	time(&now);
	if(prior == (now / freq))
		return newtimer;

	if(prior == -1)
		prior = now / freq - 1;
	else
		prior = now / freq;

	dt = localtime(&now);	
	hour = dt->tm_hour % 12;
	if(dt->tm_hour > mute[0] || dt->tm_hour < mute[1])
		return newtimer;

	if(!hour)
		hour = 12;

	if(dt->tm_hour > 11)
		apm = 1;
	else
		apm = 0;

	fp = opentcp(host, port);
	if(!fp)
		return newtimer;

	gettcp(buf, 128, fp);
	fprintf(fp, "It is %d:%d %s \r\n", hour, dt->tm_min, apmstr[apm]);
	fflush(fp);

	fd = open("/proc/uptime", O_RDONLY);
	hour = -1;
	if(fd > -1)
	{
		read(fd, buf, 128);
		close(fd);
		hour = atol(buf) / 3600;
	}

#if defined(BOOT_TIME) || defined(RUN_LVL)
	if(hour == -1)
	{
		utmp = NULL;
		memset(&uptime, 0, sizeof(uptime));
#ifdef	BOOT_TIME
		setutent();
		uptime.ut_type = BOOT_TIME;
		utmp = getutid(&uptime);
#endif
#ifdef	RUN_LVL
		if(!utmp)
		{
			setutent();
			uptime.ut_type = RUN_LVL;
			utmp = getutid(&uptime);			
		}
#endif
		if(utmp)
			hour = (now - utmp->ut_time) / 3600l;

		endutent();
	}
#endif

	if(hour > -1)
	{
		if(hour == 1)
			fprintf(fp, "The system has been up 1 hour\r\n");
		else if(hour < 48)
			fprintf(fp, "The system has been up %d hours\r\n", hour);
		else
			fprintf(fp, "The system has been up %d days\r\n", hour / 24);
		fflush(fp);
	}

	setutent();
	while(NULL != (utmp = getutent()))
	{
		++utcnt;

#ifdef	USER_PROCESS
		if(utmp->ut_type != USER_PROCESS)
			continue;
#endif

		utmp->ut_user[sizeof(utmp->ut_user)] = 0;
		if(!strcmp(utmp->ut_user, "root"))
			continue;
			
		if(!utmp->ut_user[0])
			continue;

		if(!utmp->ut_line[0])
			continue;

#ifdef	USER_PROCESS			
		if(kill(utmp->ut_pid, 0))
			continue;
#endif

		++users;
	}
	endutent();

	if(utcnt)
	{
		if(!users)
			fprintf(fp, "There are no users online\r\n");
		else if(users == 1)
			fprintf(fp, "There is 1 user online\r\n");
		else
			fprintf(fp, "There are %d users online\r\n", users);
		fflush(fp);
	}		

	if(btotal)
	{
		fprintf(fp, "The main system drives are at %d percent of capacity\r\n",
			100 - (int)(bfree / (btotal / 100)));
		fflush(fp);
	}
			
	closetcp(fp);
	return newtimer;
}
	
void	main(int argc, char **argv)
{
	int	port = getservice("speak");
	char	*maildir = getenv("MAILDIR");
	MAILBOX	*mbox = NULL, *newbox;
	char	*prog = basename(*argv);
	CONFIG	*cfg = sys_config("speak");
	time_t	now;
	char	*p;

	if(argc < 2)
		fatal(EX_USAGE, "use %s filesystems...\n", prog);

	if(!maildir)
		maildir = "/var/spool/mail";

	fs = ++argv;

	if(!port)
		fatal(EX_UNAVAILABLE, "%s: speak: service unavailable\n", prog);

	if(!cfg)
		fatal(EX_UNAVAILABLE, "%s: speak.conf: missing\n", prog);

	seek_config(cfg, "vmon");
	while(read_config(cfg))
	{
		if(NULL != (p = get_config(cfg, "mailbox")))
		{
			p = strtok(p, __SPACES);
			while(p)
			{
				newbox = (MAILBOX *)malloc(sizeof(MAILBOX) + strlen(p) + 1);
				newbox->next = mbox;
				time(&newbox->update);
				newbox->size = -1l;
				strcpy(newbox->name, p);
				mbox = newbox;
				p = strtok(NULL, __SPACES);
			}
			continue;
		}				

		if(NULL != (p = get_config(cfg, "interval")))
		{
			interval = atoi(p) * 60;
			continue;
		}

		if(NULL != (p = get_config(cfg, "frequency")))
		{
			timer = 3600 / atoi(p);
			continue;
		}
		
		if(NULL != (p = get_config(cfg, "server")))
		{
			strcpy(host, p);
			continue;
		}

		if(NULL != (p = get_config(cfg, "host")))
		{
			strcpy(host, p);
			continue;
		}

		if(NULL != (p = get_config(cfg, "alert")))
		{
			alert = atoi(p);
			continue;
		}

		if(NULL != (p = get_config(cfg, "timer")))
		{
			timer = atoi(p) * 60;
			continue;
		}

		if(NULL != (p = get_config(cfg, "mute")))
		{
			mute[0] = atoi(p);
			p = strchr(p, '-');
			if(p)
				mute[1] = atoi(strtrim(++p, __SPACES));
			continue;
		}
		
		if(NULL != (p = get_config(cfg, "maildir")))
		{
			maildir = strdup(p);
			continue;
		}
			
	}
	close_config(cfg);

	if(stricmp(prog, "vmon"))
	{
		vstat(port);
		exit(0);
	}

	pdetach(D_KEEPNONE);

	chdir(maildir);
	freq = timer;
	orig_timer = timer;
	time(&now);
	for(;;)
	{
		timer = vstat(port);
		iter = interval;
		for(;;)
		{
			vmbox(mbox, port);
			sleep(iter);
			time(&now);
			iter = timer - (now % timer) - 1;
			
			if(iter > interval)
				iter = interval;

			if(iter < 2)
			{
				sleep(iter + 2);
				break;
			}
		}			
	}
}