/*
 * raduse.c	Shows the usage of the modem lines on a terminal server.
 *
 * Version:	$Id: raduse.c,v 1.11 2002/11/14 17:08:35 aland Exp $
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Copyright 2000  The FreeRADIUS server project
 * Copyright 2000  Miquel van Smoorenburg <miquels@cistron.nl>
 */

#include "autoconf.h"

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include "sysutmp.h"
#include "conf.h"
#include "radpaths.h"
#include "libradius.h"

#ifndef _AIX
#ifdef HAVE_UTMPX_H
#undef ut_time
#define ut_time ut_xtime
#endif
#endif

#define UTSIZE (sizeof(struct utmp))

#define HOURS 19

#define MAXLINES 64

struct line {
	time_t lastout;
	time_t inuse;
	char hour[HOURS];
};
struct line lines[MAXLINES];
int nrlines = 35;

/*
 *	List the terminal servers in the logfile.
 */
static void listnas(void)
{
	FILE *fp;
	FILE *pp;
	time_t now, stop;
	struct utmp ut;
	char *p;
	int first = 1;
	char buf[128];
	int found = 0;

	/* Open the sort pipe. */
	pp = popen("sort -u", "w");

	/* Go back max. 1 day. */
	time(&now);
	stop = now - 3600 * HOURS;

	/* Open wtmp file. */
	if ((fp = fopen(RADWTMP, "r")) == NULL) {
		perror(RADWTMP);
		exit(1);
	}
	fseek(fp, -UTSIZE, SEEK_END);

	/* Read structs backwards. */
	while(1) {
		/* Rewind if needed. */
		if (!first && fseek(fp, -2 * UTSIZE, SEEK_CUR) < 0) 
			break;
		first = 0;

		/* Read struct and see if we have to stop. */
		if (ftell(fp) < (long)UTSIZE) 
			break;
		fread(&ut, UTSIZE, 1, fp);
		if (ut.ut_time < stop) 
			break;

		memset(buf, 0, sizeof(buf));
		strncpy(buf, ut.ut_line, sizeof(ut.ut_line));

		/* Get terminal server name. */
		if ((p = strchr(buf, ':')) != NULL)
			p++;
		else
			p = buf + 2;
		fprintf(pp, "%s\n", p);
		found = 1;
	}
	fclose(fp);
	pclose(pp);

	if (found == 0)
		printf("raduse: no data found over the last 24 hours.\n");
}

/*
 * Find out the usage of the ttys defined in
 * struct line lines[] for the last 21 hours.
 */
static int fillstruct(int offset, const char *nas)
{
	FILE *fp;
	time_t now, stop;
	struct utmp ut;
	int i, n;
	uint32_t port;
	int beg, end;
	char *p;
	int first = 1;
	char buf[128];
	int found = 0;

	/* Go back max. 1 day. */
	time(&now);
	stop = now - 3600 * HOURS;

	/* Open wtmp file. */
	if ((fp = fopen(RADWTMP, "r")) == NULL) {
		perror(RADWTMP);
		exit(1);
	}
	fseek(fp, -UTSIZE, SEEK_END);

	/* Read structs backwards. */
	while(1) {
		/* Rewind if needed. */
		if (!first && fseek(fp, -2 * UTSIZE, SEEK_CUR) < 0) break;
		first = 0;

		/* Read struct and see if we have to stop. */
		if (ftell(fp) < (long)UTSIZE) 
			break;
		fread(&ut, UTSIZE, 1, fp);
		if (ut.ut_time < stop) 
			break;

		memset(buf, 0, sizeof(buf));
		strncpy(buf, ut.ut_line, sizeof(ut.ut_line));

		/* Compare terminal server name. */
		if ((p = strchr(buf, ':')) != NULL)
			p++;
		else
			p = buf + 2;
		if (strcmp(p, nas) != 0)
			continue;

		found = 1;

		/* Now see which tty this was. */
		if ((p = strchr(buf, ':')) != NULL)
			*p = 0;
		else
			buf[2] = 0;

		port = strtoul(buf, NULL, 10);
		if (port == 0 && buf[0] != '0')
			continue;
		if (port < offset || port > offset + nrlines)
			continue;

		i = port - offset;

		/* Login or logout? */
		if (ut.ut_user[0] == 0) {
			lines[i].lastout = ut.ut_time;
			continue;
		}

		/* Skip type LOGIN */
		if (strncmp(ut.ut_user, "LOGIN", 5) == 0)
			continue;

		/* A login. Fill out the hour string. */
		beg = (now - ut.ut_time) / 3600;
		if (lines[i].lastout == 0) {
			lines[i].inuse = 1;
			end = 0;
		} else
			end = (now - lines[i].lastout) / 3600;
		if (beg >= HOURS) beg = HOURS - 1;
		if (end >= HOURS) end = HOURS - 1;

		for(n = end; n <= beg; n++)
			lines[i].hour[n] = lines[i].lastout ? '*' : '@';

	}
	fclose(fp);

	return found ? 0 : -1;
}

/*
 * Draw something that vaguely resembles a graph showing the
 * usage of the tty lines over the last 21 hours.
 */
static void drawit(int wide, int offset)
{
	time_t now;
	int i, n, hour;
	struct tm *tm;
	int thishour;
	int star;

	/* Find out current time. */
	time(&now);
	tm = localtime(&now);
	thishour = tm->tm_hour;

	/* Change lower spaces to dots. */
	for(i = 0; i < nrlines; i++) {
		n = 0;
		for(hour = 0; hour < HOURS; hour++) {
			if (lines[i].hour[hour]) {
				n = 1;
			} else if (n)
				lines[i].hour[hour] = '.';
		}
	}

	/* Prefix (show if line is in use now) */
	printf("now|");
	for(i = 0; i < nrlines; i++) {
		if (wide != 0)
			printf(" %c ", lines[i].inuse ? '@' : ' ');
		else
			printf("%c ", lines[i].inuse ? '@' : ' ');
	}
	printf("\n");

	/* Last 21 hours. */
	for(hour = 0; hour < HOURS; hour++) {
		printf("%02d |", thishour);
		thishour--;
		if (thishour < 0) thishour = 23;

		for(i = 0; i < nrlines; i++) {
			star = ' ';
			if (lines[i].hour[hour])
				star = lines[i].hour[hour];
			if (wide)
				printf(" %c ", star);
			else
				printf("%c ", star);
		}
		/* EOL */
		printf("\n");
	}

	/* Print a short suffix. */
	printf("---+");
	for(i = 0; i < nrlines; i++)
		printf(wide ? "---" : "--");
	printf("\n   |");
	for(i = 0; i < nrlines; i++) {
		if (wide != 0)
			printf("%02d|", i + offset);
		else
			printf("%d|", (i + offset) / 10);
	}
	if (wide == 0) {
		printf("\n   |");
		for(i = 0; i < nrlines; i++)
			printf("%d|", (i + offset) % 10);
	}
	printf("\n");
}

static void usage(void)
{
	fprintf(stderr, "Usage: raduse [-w] [-o offset] terminal-server\n");
	fprintf(stderr, "       use raduse -l to find out a list of terminal servers\n");
	exit(1);
}

int main(int argc, char **argv)
{
	int wide = 0;
	int c;
	int offset = 0;
	int list = 0;

	while((c = getopt(argc, argv, "lwo:")) != EOF) switch(c) {
		case 'w':
			wide = 1;
			break;
		case 'o':
			offset = atoi(optarg);
			break;
		case 'l':
			list = 1;
			break;
		default:
			usage();
			break;
	}

	if (list != 0) {
		listnas();
		exit(0);
	}

	if (wide != 0) 
		nrlines = 25;

	if (optind >= argc) 
		usage();

	if (fillstruct(offset, argv[optind]) < 0) {
		fprintf(stderr,
				"raduse: %s: no data found (over the last 24 hours) (try raduse -l).\n",
				argv[optind]);
		return 1;
	}
	drawit(wide, offset);

	return 0;
}