/*
** Zabbix
** Copyright (C) 2001-2016 Zabbix SIA
**
** 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
**/

#include "common.h"
#include "sysinfo.h"

int	get_diskstat(const char *devname, zbx_uint64_t *dstat)
{
	return FAIL;
}

static int	get_disk_stats(const char *devname, zbx_uint64_t *rbytes, zbx_uint64_t *wbytes, zbx_uint64_t *roper, zbx_uint64_t *woper)
{
	int			ret = SYSINFO_RET_FAIL, mib[2], drive_count;
	size_t			len;
	struct diskstats	*stats;
	int			i;

	mib[0] = CTL_HW;
	mib[1] = HW_DISKCOUNT;

	len = sizeof(drive_count);

	if (0 != sysctl(mib, 2, &drive_count, &len, NULL, 0))
		return SYSINFO_RET_FAIL;

	len = (drive_count * sizeof(struct diskstats));

	if (NULL == (stats = zbx_calloc(NULL, drive_count, len)))
		return SYSINFO_RET_FAIL;

	mib[0] = CTL_HW;
	mib[1] = HW_DISKSTATS;

	if (rbytes)
		*rbytes = 0;
	if (wbytes)
		*wbytes = 0;
	if (roper)
		*roper = 0;
	if (woper)
		*woper = 0;

	if (0 == sysctl(mib, 2, stats, &len, NULL, 0))
	{
		for (i = 0; i < drive_count; i++)
		{
			if (0 == strcmp(devname, "all") || 0 == strcmp(devname, stats[i].ds_name))
			{
				if (rbytes)
					*rbytes += stats[i].ds_rbytes;
				if (wbytes)
					*wbytes += stats[i].ds_wbytes;
				if (roper)
					*roper += stats[i].ds_rxfer;
				if (woper)
					*woper += stats[i].ds_wxfer;
				ret = SYSINFO_RET_OK;
			}
		}
	}

	free(stats);

	return ret;
}

static int	VFS_DEV_READ_BYTES(const char *devname, AGENT_RESULT *result)
{
	zbx_uint64_t	value;

	if (SYSINFO_RET_OK != get_disk_stats(devname, &value, NULL, NULL, NULL))
		return SYSINFO_RET_FAIL;

	SET_UI64_RESULT(result, value);

	return SYSINFO_RET_OK;
}

static int	VFS_DEV_READ_OPERATIONS(const char *devname, AGENT_RESULT *result)
{
	zbx_uint64_t	value;

	if (SYSINFO_RET_OK != get_disk_stats(devname, NULL, NULL, &value, NULL))
		return SYSINFO_RET_FAIL;

	SET_UI64_RESULT(result, value);

	return SYSINFO_RET_OK;
}

static int	VFS_DEV_WRITE_BYTES(const char *devname, AGENT_RESULT *result)
{
	zbx_uint64_t	value;

	if (SYSINFO_RET_OK != get_disk_stats(devname, NULL, &value, NULL, NULL))
		return SYSINFO_RET_FAIL;

	SET_UI64_RESULT(result, value);

	return SYSINFO_RET_OK;
}

static int	VFS_DEV_WRITE_OPERATIONS(const char *devname, AGENT_RESULT *result)
{
	zbx_uint64_t	value;

	if (SYSINFO_RET_OK != get_disk_stats(devname, NULL, NULL, NULL, &value))
		return SYSINFO_RET_FAIL;

	SET_UI64_RESULT(result, value);

	return SYSINFO_RET_OK;
}

int	VFS_DEV_WRITE(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result)
{
	const MODE_FUNCTION	fl[] =
	{
		{"bytes",	VFS_DEV_WRITE_BYTES},
		{"operations",	VFS_DEV_WRITE_OPERATIONS},
		{NULL,		0}
	};

	char	devname[MAX_STRING_LEN];
	char	mode[MAX_STRING_LEN];
	int	i;

	if (num_param(param) > 3)
		return SYSINFO_RET_FAIL;

	if (0 != get_param(param, 1, devname, sizeof(devname)))
		*devname = '\0';

	/* default parameter */
	if (*devname == '\0')
		zbx_snprintf(devname, sizeof(devname), "all");

	if (0 != get_param(param, 2, mode, sizeof(mode)))
		*mode = '\0';

	/* default parameter */
	if (*mode == '\0')
		zbx_snprintf(mode, sizeof(mode), "operations");

	for (i = 0; fl[i].mode != 0; i++)
		if (0 == strncmp(mode, fl[i].mode, MAX_STRING_LEN))
			return (fl[i].function)(devname, result);

	return SYSINFO_RET_FAIL;
}

int	VFS_DEV_READ(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result)
{
	const MODE_FUNCTION	fl[] =
	{
		{"bytes",	VFS_DEV_READ_BYTES},
		{"operations",	VFS_DEV_READ_OPERATIONS},
		{NULL,		0}
	};

	char	devname[MAX_STRING_LEN];
	char	mode[MAX_STRING_LEN];
	int	i;

	if (num_param(param) > 3)
		return SYSINFO_RET_FAIL;

	if (0 != get_param(param, 1, devname, sizeof(devname)))
		*devname = '\0';

	/* default parameter */
	if (*devname == '\0')
		zbx_snprintf(devname, sizeof(devname), "all");

	if (0 != get_param(param, 2, mode, sizeof(mode)))
		*mode = '\0';

	/* default parameter */
	if (*mode == '\0')
		zbx_snprintf(mode, sizeof(mode), "operations");

	for (i = 0; fl[i].mode != 0; i++)
		if (0 == strncmp(mode, fl[i].mode, MAX_STRING_LEN))
			return (fl[i].function)(devname, result);

	return SYSINFO_RET_FAIL;
}
