/*
** Copyright (C) 2001-2025 Zabbix SIA
**
** This program is free software: you can redistribute it and/or modify it under the terms of
** the GNU Affero General Public License as published by the Free Software Foundation, version 3.
**
** 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 Affero General Public License for more details.
**
** You should have received a copy of the GNU Affero General Public License along with this program.
** If not, see <https://www.gnu.org/licenses/>.
**/

#include "zbxsysinfo.h"
#include "../sysinfo.h"

int	system_swap_size(AGENT_REQUEST *request, AGENT_RESULT *result)
{
#ifdef HAVE_LIBPERFSTAT
#define ZBX_PERFSTAT_PAGE_SHIFT	12	/* 4 KB */
	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 (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, 0 != mem.pgsp_total ? 100.0 * (mem.pgsp_free / (double)mem.pgsp_total) : 100.0);
	}
	else if (0 == strcmp(mode, "pused"))
	{
		SET_DBL_RESULT(result, 0 != mem.pgsp_total ? 100.0 - 100.0 * (mem.pgsp_free / (double)mem.pgsp_total) :
			0.0);
	}
	else
	{
		SET_MSG_RESULT(result, zbx_strdup(NULL, "Invalid second parameter."));
		return SYSINFO_RET_FAIL;
	}

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

	return SYSINFO_RET_FAIL;
#endif
}
