/*
** Zabbix
** Copyright (C) 2001-2021 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"
#include "log.h"

#define ZBX_PERFSTAT_PAGE_SHIFT	12	/* 4 KB */

int	SYSTEM_SWAP_SIZE(AGENT_REQUEST *request, AGENT_RESULT *result)
{
#ifdef HAVE_LIBPERFSTAT
	perfstat_memory_total_t	mem;
	char			*swapdev, *mode;

	if (2 < request->nparam)
	{
		SET_MSG_RESULT(result, zbx_strdup(NULL, "Too many parameters."));
		return SYSINFO_RET_FAIL;
	}

	swapdev = get_rparam(request, 0);
	mode = get_rparam(request, 1);

	if (NULL != swapdev && '\0' != *swapdev && 0 != strcmp(swapdev, "all"))
	{
		SET_MSG_RESULT(result, zbx_strdup(NULL, "Invalid first parameter."));
		return SYSINFO_RET_FAIL;
	}

	if (1 != perfstat_memory_total(NULL, &mem, sizeof(perfstat_memory_total_t), 1))
	{
		SET_MSG_RESULT(result, zbx_dsprintf(NULL, "Cannot obtain system information: %s", zbx_strerror(errno)));
		return SYSINFO_RET_FAIL;
	}

	if (0 == mem.pgsp_total && (NULL == mode || 0 != strcmp(mode, "total")))
	{
		SET_MSG_RESULT(result, zbx_strdup(NULL, "Cannot be calculated because swap file size is 0."));
		return SYSINFO_RET_FAIL;
	}
	else
	{
		if (NULL == mode || '\0' == *mode || 0 == strcmp(mode, "free"))
		{
			SET_UI64_RESULT(result, mem.pgsp_free << ZBX_PERFSTAT_PAGE_SHIFT);
		}
		else if (0 == strcmp(mode, "total"))
		{
			SET_UI64_RESULT(result, mem.pgsp_total << ZBX_PERFSTAT_PAGE_SHIFT);
		}
		else if (0 == strcmp(mode, "used"))
		{
			SET_UI64_RESULT(result, (mem.pgsp_total - mem.pgsp_free) << ZBX_PERFSTAT_PAGE_SHIFT);
		}
		else if (0 == strcmp(mode, "pfree"))
		{
			SET_DBL_RESULT(result, 100.0 * (mem.pgsp_free / (double)mem.pgsp_total));
		}
		else if (0 == strcmp(mode, "pused"))
		{
			SET_DBL_RESULT(result, 100.0 - 100.0 * (mem.pgsp_free / (double)mem.pgsp_total));
		}
		else
		{
			SET_MSG_RESULT(result, zbx_strdup(NULL, "Invalid second parameter."));
			return SYSINFO_RET_FAIL;
		}
	}

	return SYSINFO_RET_OK;
#else
	SET_MSG_RESULT(result, zbx_strdup(NULL, "Agent was compiled without support for Perfstat API."));

	return SYSINFO_RET_FAIL;
#endif
}
