/******************************************************************************
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*****************************************************************************/

const char *progname = "check_disk";
const char *revision = "$Revision$";
const char *copyright = "1999-2003";
const char *authors = "Nagios Plugin Development Team";
const char *email = "nagiosplug-devel@lists.sourceforge.net";

const char *summary = "\
This plugin checks the amount of used disk space on a mounted file system\n\
and generates an alert if free space is less than one of the threshold values.";

const char *option_summary = "\
-w limit -c limit [-p path | -x device] [-t timeout] [-m] [-e]\n\
        [-v] [-q]";

const char *options = "\
 -w, --warning=INTEGER\n\
   Exit with WARNING status if less than INTEGER kilobytes of disk are free\n\
 -w, --warning=PERCENT%%\n\
   Exit with WARNING status if less than PERCENT of disk space is free\n\
 -c, --critical=INTEGER\n\
   Exit with CRITICAL status if less than INTEGER kilobytes of disk are free\n\
 -c, --critical=PERCENT%%\n\
   Exit with CRITCAL status if less than PERCENT of disk space is free\n\
 -u, --units=STRING\n\
    Choose bytes, kB, MB, GB, TB (default: MB)\n\
 -k, --kilobytes\n\
    Same as '--units kB'\n\
 -m, --megabytes\n\
    Same as '--units MB'\n\
 -l, --local\n\
    Only check local filesystems\n\
 -p, --path=PATH, --partition=PARTITION\n\
    Path or partition (may be repeated)\n\
 -x, --exclude_device=PATH <STRING>\n\
    Ignore device (only works if -p unspecified)\n\
 -X, --exclude-type=TYPE <STRING>\n\
    Ignore all filesystems of indicated type (may be repeated)\n\
 -M, --mountpoint\n\
    Display the mountpoint instead of the partition\n\
 -e, --errors-only\n\
    Display only devices/mountpoints with errors\n\
 -C, --clear\n\
    Clear thresholds\n\
 -v, --verbose\n\
    Show details for command-line debugging (do not use with nagios server)\n\
 -h, --help\n\
    Print detailed help screen\n\
 -V, --version\n\
    Print version information\n";

const char *notes = "\
\n";

const char *examples = "\
 check_disk -w 10% -c 5% -p /tmp -p /var -C -w 100000 -c 50000 -p /\n\
   Checks /tmp and /var at 10%,5% and / at 100MB, 50MB\n\
\n";

#include "common.h"
#if HAVE_INTTYPES_H
# include <inttypes.h>
#endif
#include <assert.h>
#include "popen.h"
#include "utils.h"
#include <stdarg.h>
#include "../lib/fsusage.h"
#include "../lib/mountlist.h"
#if HAVE_LIMITS_H
# include <limits.h>
#endif

/* If nonzero, show inode information. */
static int inode_format;

/* If nonzero, show even filesystems with zero size or
   uninteresting types. */
static int show_all_fs = 1;

/* If nonzero, show only local filesystems.  */
static int show_local_fs = 0;

/* If positive, the units to use when printing sizes;
   if negative, the human-readable base.  */
static int output_block_size;

/* If nonzero, invoke the `sync' system call before getting any usage data.
   Using this option can make df very slow, especially with many or very
   busy disks.  Note that this may make a difference on some systems --
   SunOs4.1.3, for one.  It is *not* necessary on Linux.  */
static int require_sync = 0;

/* A filesystem type to display. */

struct name_list
{
  char *name;
  int found;
  int w_df;
  int c_df;
  float w_dfp;
  float c_dfp;
  struct name_list *name_next;
};

/* Linked list of filesystem types to display.
   If `fs_select_list' is NULL, list all types.
   This table is generated dynamically from command-line options,
   rather than hardcoding into the program what it thinks are the
   valid filesystem types; let the user specify any filesystem type
   they want to, and if there are any filesystems of that type, they
   will be shown.

   Some filesystem types:
   4.2 4.3 ufs nfs swap ignore io vm efs dbg */

static struct name_list *fs_select_list;

/* Linked list of filesystem types to omit.
   If the list is empty, don't exclude any types.  */

static struct name_list *fs_exclude_list;

static struct name_list *dp_exclude_list;

static struct name_list *path_select_list;

static struct name_list *dev_select_list;

/* Linked list of mounted filesystems. */
static struct mount_entry *mount_list;

/* For long options that have no equivalent short option, use a
   non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
enum
{
  SYNC_OPTION = CHAR_MAX + 1,
  NO_SYNC_OPTION,
  BLOCK_SIZE_OPTION
};

#ifdef _AIX
 #pragma alloca
#endif

int process_arguments (int, char **);
int validate_arguments (int, int, float, float, char *);
int check_disk (int usp, int free_disk);
int walk_name_list (struct name_list *list, const char *name);
void print_help (void);
void print_usage (void);

int w_df = -1;
int c_df = -1;
float w_dfp = -1.0;
float c_dfp = -1.0;
char *path = "";
char *exclude_device = "";
char *units = "MB";
unsigned long mult = 1024 * 1024;
int verbose = 0;
int erronly = FALSE;
int display_mntp = FALSE;

/* Linked list of mounted filesystems. */
static struct mount_entry *mount_list;

int
main (int argc, char **argv)
{
	int usp = -1;
	int total_disk = -1;
	int used_disk = -1;
	int free_disk = -1;
	int result = STATE_UNKNOWN;
	int disk_result = STATE_UNKNOWN;
	char *command_line = "";
	char input_buffer[MAX_INPUT_BUFFER];
	char file_system[MAX_INPUT_BUFFER];
	char mntp[MAX_INPUT_BUFFER];
	char *output = "";
	char *details = "";
	float free_space, free_space_pct, total_space;

	struct mount_entry *me;
	struct fs_usage fsp;
	struct name_list *temp_list;
	char *disk;

	mount_list = read_filesystem_list (0);

	if (process_arguments (argc, argv) != OK)
		usage ("Could not parse arguments\n");

	for (me = mount_list; me; me = me->me_next) {

		if (path_select_list &&
		     (walk_name_list (path_select_list, me->me_mountdir) ||
		      walk_name_list (path_select_list, me->me_devname) ) )
			get_fs_usage (me->me_mountdir, me->me_devname, &fsp);
		else if (dev_select_list || path_select_list)
			continue;
		else if (me->me_remote && show_local_fs)
			continue;
		else if (me->me_dummy && !show_all_fs)
			continue;
		else if (fs_exclude_list && walk_name_list (fs_exclude_list, me->me_type))
			continue;
		else if (dp_exclude_list && 
		         walk_name_list (dp_exclude_list, me->me_devname) ||
		         walk_name_list (dp_exclude_list, me->me_mountdir))
			continue;
		else
			get_fs_usage (me->me_mountdir, me->me_devname, &fsp);

		if (fsp.fsu_blocks && strcmp ("none", me->me_mountdir)) {
			usp = (fsp.fsu_blocks - fsp.fsu_bavail) * 100 / fsp.fsu_blocks;
			disk_result = check_disk (usp, fsp.fsu_bavail);
			result = max_state (disk_result, result);
			if (disk_result==STATE_OK && erronly && !verbose)
				continue;

			free_space = (float)fsp.fsu_bavail*fsp.fsu_blocksize/mult;
			free_space_pct = (float)fsp.fsu_bavail*100/fsp.fsu_blocks;
			total_space = (float)fsp.fsu_blocks*fsp.fsu_blocksize/mult;
			if (disk_result!=STATE_OK || verbose>=0)
				asprintf (&output, "%s [%.0f %s (%.0f%%) free on %s]",
				          output,
				          free_space,
				          units,
				          free_space_pct,
				          (!strcmp(file_system, "none") || display_mntp) ? me->me_devname : me->me_mountdir);
			asprintf (&details, "%s\n%.0f of %.0f %s (%.0f%%) free on %s (type %s mounted on %s) warn:%d crit:%d warn%%:%.0f%% crit%%:%.0f%%",
			          details,
			          free_space,
			          total_space,
			          units,
			          free_space_pct,
			          me->me_devname,
			          me->me_type,
			          me->me_mountdir,
				  w_df, c_df, w_dfp, c_dfp);
		}

	}

	if (verbose > 2)
		asprintf (&output, "%s%s", output, details);

	/* Override result if paths specified and not found */
	temp_list = path_select_list;
	while (temp_list) {
		if (temp_list->found != TRUE) {
			asprintf (&output, "%s [%s not found]", output, temp_list->name);
			result = STATE_CRITICAL;
		}
		temp_list = temp_list->name_next;
	}

	terminate (result, "DISK %s%s\n", state_text (result), output, details);
}




/* process command-line arguments */
int
process_arguments (int argc, char **argv)
{
	int c;
	struct name_list *se;
	struct name_list **pathtail = &path_select_list;
	struct name_list **devtail = &dev_select_list;
	struct name_list **fstail = &fs_exclude_list;
	struct name_list **dptail = &dp_exclude_list;
	struct name_list *temp_list;
	int result = OK;

	int option_index = 0;
	static struct option long_options[] = {
		{"timeout", required_argument, 0, 't'},
		{"warning", required_argument, 0, 'w'},
		{"critical", required_argument, 0, 'c'},
		{"local", required_argument, 0, 'l'},
		{"kilobytes", required_argument, 0, 'k'},
		{"megabytes", required_argument, 0, 'm'},
		{"units", required_argument, 0, 'u'},
		{"path", required_argument, 0, 'p'},
		{"partition", required_argument, 0, 'p'},
		{"exclude_device", required_argument, 0, 'x'},
		{"exclude-type", required_argument, 0, 'X'},
		{"mountpoint", no_argument, 0, 'M'},
		{"errors-only", no_argument, 0, 'e'},
		{"verbose", no_argument, 0, 'v'},
		{"quiet", no_argument, 0, 'q'},
		{"clear", no_argument, 0, 'C'},
		{"version", no_argument, 0, 'V'},
		{"help", no_argument, 0, 'h'},
		{0, 0, 0, 0}
	};

	if (argc < 2)
		return ERROR;

	se = (struct name_list *) malloc (sizeof (struct name_list));
	se->name = strdup ("iso9660");
	se->name_next = NULL;
	*fstail = se;
	fstail = &se->name_next;

	for (c = 1; c < argc; c++)
		if (strcmp ("-to", argv[c]) == 0)
			strcpy (argv[c], "-t");

	while (1) {
		c = getopt_long (argc, argv, "+?VqhveCt:c:w:u:p:x:X:mklM", long_options, &option_index);

		if (c == -1 || c == EOF)
			break;

		switch (c) {
		case 't':									/* timeout period */
			if (is_integer (optarg)) {
				timeout_interval = atoi (optarg);
				break;
			}
			else {
				usage ("Timeout Interval must be an integer!\n");
			}
		case 'w':									/* warning time threshold */
			if (is_intnonneg (optarg)) {
				w_df = atoi (optarg);
				break;
			}
			else if (strpbrk (optarg, ",:") &&
							 strstr (optarg, "%") &&
							 sscanf (optarg, "%d%*[:,]%f%%", &w_df, &w_dfp) == 2) {
				break;
			}
			else if (strstr (optarg, "%") && sscanf (optarg, "%f%%", &w_dfp) == 1) {
				break;
			}
			else {
				usage ("Warning threshold must be integer or percentage!\n");
			}
		case 'c':									/* critical time threshold */
			if (is_intnonneg (optarg)) {
				c_df = atoi (optarg);
				break;
			}
			else if (strpbrk (optarg, ",:") &&
							 strstr (optarg, "%") &&
							 sscanf (optarg, "%d%*[,:]%f%%", &c_df, &c_dfp) == 2) {
				break;
			}
			else if (strstr (optarg, "%") && sscanf (optarg, "%f%%", &c_dfp) == 1) {
				break;
			}
			else {
				usage ("Critical threshold must be integer or percentage!\n");
			}
		case 'u':
			if (! strcmp (optarg, "bytes")) {
				mult = 1;
				units = "B";
			} else if (! strcmp (optarg, "kB")) {
				mult = 1024;
				units = "kB";
			} else if (! strcmp (optarg, "MB")) {
				mult = 1024 * 1024;
				units = "MB";
			} else if (! strcmp (optarg, "GB")) {
				mult = 1024 * 1024 * 1024;
				units = "GB";
			} else if (! strcmp (optarg, "TB")) {
				mult = (unsigned long)1024 * 1024 * 1024 * 1024;
				units = "TB";
			} else {
				terminate (STATE_UNKNOWN, "unit type %s not known\n", optarg);
			}
			break;
		case 'k': /* display mountpoint */
			mult = 1024;
			units = "kB";
			break;
		case 'm': /* display mountpoint */
			mult = 1024 * 1024;
			units = "MB";
			break;
		case 'l':
			show_local_fs = 1;			
			break;
		case 'p':									/* select path */
			se = (struct name_list *) malloc (sizeof (struct name_list));
			se->name = strdup (optarg);
			se->name_next = NULL;
			se->w_df = w_df;
			se->c_df = c_df;
			se->w_dfp = w_dfp;
			se->c_dfp = c_dfp;
			*pathtail = se;
			pathtail = &se->name_next;
			break;
 		case 'x':									/* exclude path or partition */
			se = (struct name_list *) malloc (sizeof (struct name_list));
			se->name = strdup (optarg);
			se->name_next = NULL;
			*dptail = se;
			dptail = &se->name_next;
			break;
		case 'X':									/* exclude file system type */
			se = (struct name_list *) malloc (sizeof (struct name_list));
			se->name = strdup (optarg);
			se->name_next = NULL;
			*fstail = se;
			fstail = &se->name_next;
			break;
		case 'v':									/* verbose */
			verbose++;
			break;
		case 'q':									/* verbose */
			verbose--;
			break;
		case 'e':
			erronly = TRUE;
			break;
		case 'M': /* display mountpoint */
			display_mntp = TRUE;
			break;
		case 'C':
			w_df = -1;
			c_df = -1;
			w_dfp = -1.0;
			c_dfp = -1.0;
			break;
		case 'V':									/* version */
			print_revision (progname, revision);
			exit (STATE_OK);
		case 'h':									/* help */
			print_help ();
			exit (STATE_OK);
		case '?':									/* help */
			usage ("check_disk: unrecognized option\n");
			break;
		}
	}

	/* Support for "check_disk warn crit [fs]" with thresholds at used level */
	c = optind;
	if (w_dfp == -1 && argc > c && is_intnonneg (argv[c]))
		w_dfp = (100.0 - atof (argv[c++]));

	if (c_dfp == -1 && argc > c && is_intnonneg (argv[c]))
		c_dfp = (100.0 - atof (argv[c++]));

	if (argc > c && strlen (path) == 0) {
		se = (struct name_list *) malloc (sizeof (struct name_list));
		se->name = strdup (argv[c++]);
		se->name_next = NULL;
		se->w_df = w_df;
		se->c_df = c_df;
		se->w_dfp = w_dfp;
		se->c_dfp = c_dfp;
		*pathtail = se;
	}

	if (path_select_list) {
		temp_list = path_select_list;
		while (temp_list) {
			if (validate_arguments (temp_list->w_df, temp_list->c_df, temp_list->w_dfp, temp_list->c_dfp, temp_list->name) == ERROR)
				result = ERROR;
			temp_list = temp_list->name_next;
		}
		return result;
	} else {
		return validate_arguments (w_df, c_df, w_dfp, c_dfp, NULL);
	}
}


void print_path (char *path) 
{
	if (path)
		printf (" for %s", path);
	printf ("\n");
}

int
validate_arguments (int w, int c, float wp, float cp, char *path)
{
	if (w < 0 && c < 0 && wp < 0 && cp < 0) {
		printf ("INPUT ERROR: No thresholds specified");
		print_path (path);
		return ERROR;
	}
	else if ((wp >= 0 || cp >= 0)
					 && (wp < 0 || cp < 0 || wp > 100 || cp > 100
							 || cp > wp)) {
		printf
			("INPUT ERROR: C_DFP (%f) should be less than W_DFP (%.1f) and both should be between zero and 100 percent, inclusive",
			 cp, wp);
		print_path (path);
		return ERROR;
	}
	else if ((w > 0 || c > 0) && (w < 0 || c < 0 || c > w)) {
		printf
			("INPUT ERROR: C_DF (%d) should be less than W_DF (%d) and both should be greater than zero",
			 c, w);
		print_path (path);
		return ERROR;
	}
	else {
		return OK;
	}
}




int
check_disk (int usp, int free_disk)
{
	int result = STATE_UNKNOWN;
	/* check the percent used space against thresholds */
	if (usp >= 0 && usp >= (100.0 - c_dfp))
		result = STATE_CRITICAL;
	else if (c_df >= 0 && free_disk <= c_df)
		result = STATE_CRITICAL;
	else if (usp >= 0 && usp >= (100.0 - w_dfp))
		result = STATE_WARNING;
	else if (w_df >= 0 && free_disk <= w_df)
		result = STATE_WARNING;
	else if (usp >= 0.0)
		result = STATE_OK;
	return result;
}



int
walk_name_list (struct name_list *list, const char *name)
{
	while (list) {
		if (! strcmp(list->name, name)) {
			list->found = 1;
			/* if required for name_lists that have not saved w_df, etc (eg exclude lists) */
			if (list->w_df) w_df = list->w_df;
			if (list->c_df) c_df = list->c_df;
			if (list->w_dfp) w_dfp = list->w_dfp;
			if (list->c_dfp) c_dfp = list->c_dfp;
			return TRUE;
		}
		list = list->name_next;
	}
	return FALSE;
}




void
print_help (void)
{
	print_revision (progname, revision);
	printf ("Copyright (c) %s %s\n\t<%s>\n\n%s\n",
	         copyright, authors, email, summary);
	print_usage ();
	printf ("\nOptions:\n");
	printf (options);
	printf (notes);
	printf ("Examples:\n%s", examples);
	support ();
}

void
print_usage (void)
{
	printf
		("Usage: %s %s\n"
		 "       %s (-h|--help)\n"
		 "       %s (-V|--version)\n", progname, option_summary, progname, progname);
}