path: root/lib/plugins/stonith/apcmastersnmp.c

/*
 * Stonith module for APC Masterswitch (SNMP)
 * Copyright (c) 2001 Andreas Piesk <a.piesk@gmx.net>
 * Mangled by Sun Jiang Dong <sunjd@cn.ibm.com>, IBM, 2005
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.*
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <lha_internal.h>

/* device ID */
#define	DEVICE				"APC MasterSwitch (SNMP)"

#include "stonith_plugin_common.h"
#undef FREE	/* defined by snmp stuff */

#ifdef PACKAGE_BUGREPORT
#undef PACKAGE_BUGREPORT
#endif
#ifdef PACKAGE_NAME
#undef PACKAGE_NAME
#endif
#ifdef PACKAGE_STRING
#undef PACKAGE_STRING
#endif
#ifdef PACKAGE_TARNAME
#undef PACKAGE_TARNAME
#endif
#ifdef PACKAGE_VERSION
#undef PACKAGE_VERSION
#endif

#ifdef HAVE_NET_SNMP_NET_SNMP_CONFIG_H
#       include <net-snmp/net-snmp-config.h>
#       include <net-snmp/net-snmp-includes.h>
#       include <net-snmp/agent/net-snmp-agent-includes.h>
#       define  INIT_AGENT()    init_master_agent()
#else
#       include <ucd-snmp/ucd-snmp-config.h>
#       include <ucd-snmp/ucd-snmp-includes.h>
#       include <ucd-snmp/ucd-snmp-agent-includes.h>
#       ifndef NETSNMP_DS_APPLICATION_ID
#               define NETSNMP_DS_APPLICATION_ID        DS_APPLICATION_ID
#       endif
#       ifndef NETSNMP_DS_AGENT_ROLE
#               define NETSNMP_DS_AGENT_ROLE    DS_AGENT_ROLE
#       endif
#       define netsnmp_ds_set_boolean   ds_set_boolean
#       define  INIT_AGENT()    init_master_agent(161, NULL, NULL)
#endif

#define PIL_PLUGIN              apcmastersnmp
#define PIL_PLUGIN_S            "apcmastersnmp"
#define PIL_PLUGINLICENSE 	LICENSE_LGPL
#define PIL_PLUGINLICENSEURL 	URL_LGPL
#include <pils/plugin.h>

#define	DEBUGCALL					\
    if (Debug) {					\
    	LOG(PIL_DEBUG, "%s: called.", __FUNCTION__);	\
    }

static StonithPlugin *	apcmastersnmp_new(const char *);
static void	apcmastersnmp_destroy(StonithPlugin *);
static const char * const *	apcmastersnmp_get_confignames(StonithPlugin *);
static int	apcmastersnmp_set_config(StonithPlugin *, StonithNVpair *);
static const char *	apcmastersnmp_getinfo(StonithPlugin * s, int InfoType);
static int	apcmastersnmp_status(StonithPlugin * );
static int	apcmastersnmp_reset_req(StonithPlugin * s, int request, const char * host);
static char **	apcmastersnmp_hostlist(StonithPlugin  *);

static struct stonith_ops apcmastersnmpOps ={
	apcmastersnmp_new,		/* Create new STONITH object	*/
	apcmastersnmp_destroy,		/* Destroy STONITH object	*/
	apcmastersnmp_getinfo,		/* Return STONITH info string	*/
	apcmastersnmp_get_confignames,	/* Get configuration parameters	*/
	apcmastersnmp_set_config,	/* Set configuration */
	apcmastersnmp_status,		/* Return STONITH device status	*/
	apcmastersnmp_reset_req,	/* Request a reset */
	apcmastersnmp_hostlist,		/* Return list of supported hosts */
};

PIL_PLUGIN_BOILERPLATE2("1.0", Debug)
static const PILPluginImports*  PluginImports;
static PILPlugin*               OurPlugin;
static PILInterface*		OurInterface;
static StonithImports*		OurImports;
static void*			interfprivate;

PIL_rc
PIL_PLUGIN_INIT(PILPlugin*us, const PILPluginImports* imports);

PIL_rc
PIL_PLUGIN_INIT(PILPlugin*us, const PILPluginImports* imports)
{
	/* Force the compiler to do a little type checking */
	(void)(PILPluginInitFun)PIL_PLUGIN_INIT;
	DEBUGCALL;

	PluginImports = imports;
	OurPlugin = us;

	/* Register ourself as a plugin */
	imports->register_plugin(us, &OurPIExports);  

	/*  Register our interface implementation */
 	return imports->register_interface(us, PIL_PLUGINTYPE_S
	,	PIL_PLUGIN_S
	,	&apcmastersnmpOps
	,	NULL		/*close */
	,	&OurInterface
	,	(void*)&OurImports
	,	&interfprivate); 
}

/*
 * APCMaster tested with APC Masterswitch 9212
 */

/* outlet commands / status codes */
#define OUTLET_ON			1
#define OUTLET_OFF			2
#define OUTLET_REBOOT			3
#define OUTLET_NO_CMD_PEND		2

/* oids */
#define OID_IDENT			".1.3.6.1.4.1.318.1.1.12.1.5.0"
#define OID_NUM_OUTLETS			".1.3.6.1.4.1.318.1.1.12.1.8.0"
#define OID_OUTLET_NAMES		".1.3.6.1.4.1.318.1.1.12.3.4.1.1.2.%i"
#define OID_OUTLET_STATE		".1.3.6.1.4.1.318.1.1.12.3.3.1.1.4.%i"
#define OID_OUTLET_COMMAND_PENDING	".1.3.6.1.4.1.318.1.1.12.3.5.1.1.5.%i"
#define OID_OUTLET_REBOOT_DURATION	".1.3.6.1.4.1.318.1.1.12.3.4.1.1.6.%i"

/*
	snmpset -c private -v1 172.16.0.32:161
		".1.3.6.1.4.1.318.1.1.12.3.3.1.1.4.1" i 1
	The last octet in the OID is the plug number. The value can
	be 1 thru 8 because there are 8 power plugs on this device.
	The integer that can be set is as follows: 1=on, 2=off, and
	3=reset
*/

/* own defines */
#define MAX_STRING		128
#define ST_PORT			"port"

/* structur of stonith object */
struct pluginDevice {
	StonithPlugin		sp;		/* StonithPlugin object */
	const char*		pluginid;	/* id of object		*/
	const char*		idinfo;		/* type of device	*/
	struct snmp_session*	sptr;		/* != NULL->session created */
	char *			hostname;	/* masterswitch's hostname  */
						/* or  ip addr		*/
	int			port;		/* snmp port		*/
	char *			community;	/* snmp community (r/w)	*/
	int			num_outlets;	/* number of outlets	*/
};

/* for checking hardware (issue a warning if mismatch) */
static const char* APC_tested_ident[] = {"AP9606","AP7920","AP7921","AP7900","AP_other_well_tested"};

/* constant strings */
static const char *pluginid = "APCMS-SNMP-Stonith";
static const char *NOTpluginID = "APCMS SNMP device has been destroyed";

#include "stonith_config_xml.h"

#define XML_PORT_SHORTDESC \
	XML_PARM_SHORTDESC_BEGIN("en") \
	ST_PORT \
	XML_PARM_SHORTDESC_END

#define XML_PORT_LONGDESC \
	XML_PARM_LONGDESC_BEGIN("en") \
	"The port number on which the SNMP server is running on the STONITH device" \
	XML_PARM_LONGDESC_END

#define XML_PORT_PARM \
	XML_PARAMETER_BEGIN(ST_PORT, "string", "1", "0") \
	  XML_PORT_SHORTDESC \
	  XML_PORT_LONGDESC \
	XML_PARAMETER_END

static const char *apcmastersnmpXML = 
  XML_PARAMETERS_BEGIN
    XML_IPADDR_PARM
    XML_PORT_PARM
    XML_COMMUNITY_PARM
  XML_PARAMETERS_END;

/*
 * own prototypes 
 */

static void APC_error(struct snmp_session *sptr, const char *fn
,	const char *msg);
static struct snmp_session *APC_open(char *hostname, int port
,	char *community);
static void *APC_read(struct snmp_session *sptr, const char *objname
,	int type);
static int APC_write(struct snmp_session *sptr, const char *objname
,	char type, char *value);

static void 
APC_error(struct snmp_session *sptr, const char *fn, const char *msg)
{
    int snmperr = 0;
    int cliberr = 0;
    char *errstr;

    snmp_error(sptr, &cliberr, &snmperr, &errstr);
    LOG(PIL_CRIT
    ,	"%s: %s (cliberr: %i / snmperr: %i / error: %s)."
    ,	fn, msg, cliberr, snmperr, errstr);
    free(errstr);
}


/*
 *  creates a snmp session
 */
static struct snmp_session *
APC_open(char *hostname, int port, char *community)
{
    static struct snmp_session session;
    struct snmp_session *sptr;

    DEBUGCALL;

    /* create session */
    snmp_sess_init(&session);

    /* fill session */
    session.peername = hostname;
    session.version = SNMP_VERSION_1;
    session.remote_port = port;
    session.community = (u_char *)community;
    session.community_len = strlen(community);
    session.retries = 5;
    session.timeout = 1000000;

    /* open session */
    sptr = snmp_open(&session);

    if (sptr == NULL) {
	APC_error(&session, __FUNCTION__, "cannot open snmp session");
    }

    /* return pointer to opened session */
    return (sptr);
}

/*
 * parse config
 */

/*
 * read value of given oid and return it as string
 */
static void *
APC_read(struct snmp_session *sptr, const char *objname, int type)
{
    oid name[MAX_OID_LEN];
    size_t namelen = MAX_OID_LEN;
    struct variable_list *vars;
    struct snmp_pdu *pdu;
    struct snmp_pdu *resp;
    static char response_str[MAX_STRING];
    static int response_int;

    DEBUGCALL;

    /* convert objname into oid; return NULL if invalid */
    if (!read_objid(objname, name, &namelen)) {
        LOG(PIL_CRIT, "%s: cannot convert %s to oid.", __FUNCTION__, objname);
	return (NULL);
    }

    /* create pdu */
    if ((pdu = snmp_pdu_create(SNMP_MSG_GET)) != NULL) {

	/* get-request have no values */
	snmp_add_null_var(pdu, name, namelen);

	/* send pdu and get response; return NULL if error */
	if (snmp_synch_response(sptr, pdu, &resp) == SNMPERR_SUCCESS) {

	    /* request succeed, got valid response ? */
	    if (resp->errstat == SNMP_ERR_NOERROR) {

		/* go through the returned vars */
		for (vars = resp->variables; vars;
		     vars = vars->next_variable) {

		    /* return response as string */
		    if ((vars->type == type) && (type == ASN_OCTET_STR)) {
			memset(response_str, 0, MAX_STRING);
			strncpy(response_str, (char *)vars->val.string,
				MIN(vars->val_len, MAX_STRING));
			snmp_free_pdu(resp);
			return ((void *) response_str);
		    }
		    /* return response as integer */
		    if ((vars->type == type) && (type == ASN_INTEGER)) {
			response_int = *vars->val.integer;
			snmp_free_pdu(resp);
			return ((void *) &response_int);
		    }
		}
	    }else{
		LOG(PIL_CRIT, "%s: error in response packet, reason %ld [%s]."
		,   __FUNCTION__, resp->errstat, snmp_errstring(resp->errstat));
	    }
	}else{
            APC_error(sptr, __FUNCTION__, "error sending/receiving pdu");
        }
	/* free repsonse pdu (necessary?) */
	snmp_free_pdu(resp);
    }else{
        APC_error(sptr, __FUNCTION__, "cannot create pdu");
    }
    /* error: return nothing */
    return (NULL);
}

/*
 * write value of given oid
 */
static int
APC_write(struct snmp_session *sptr, const char *objname, char type,
	  char *value)
{
    oid name[MAX_OID_LEN];
    size_t namelen = MAX_OID_LEN;
    struct snmp_pdu *pdu;
    struct snmp_pdu *resp;

    DEBUGCALL;

    /* convert objname into oid; return FALSE if invalid */
    if (!read_objid(objname, name, &namelen)) {
        LOG(PIL_CRIT, "%s: cannot convert %s to oid.", __FUNCTION__, objname);
        return (FALSE);
    }

    /* create pdu */
    if ((pdu = snmp_pdu_create(SNMP_MSG_SET)) != NULL) {

	/* add to be written value to pdu */
	snmp_add_var(pdu, name, namelen, type, value);

	/* send pdu and get response; return NULL if error */
	if (snmp_synch_response(sptr, pdu, &resp) == STAT_SUCCESS) {

	    /* go through the returned vars */
	    if (resp->errstat == SNMP_ERR_NOERROR) {

		/* request successful done */
		snmp_free_pdu(resp);
		return (TRUE);

	    }else{
		LOG(PIL_CRIT, "%s: error in response packet, reason %ld [%s]."
		,   __FUNCTION__, resp->errstat, snmp_errstring(resp->errstat));
	    }
	}else{
            APC_error(sptr, __FUNCTION__, "error sending/receiving pdu");
        }
	/* free pdu (again: necessary?) */
	snmp_free_pdu(resp);
    }else{
        APC_error(sptr, __FUNCTION__, "cannot create pdu");
    }
    /* error */
    return (FALSE);
}

/*
 * return the status for this device 
 */

static int
apcmastersnmp_status(StonithPlugin * s)
{
    struct pluginDevice *ad;
    char *ident;
    int i;

    DEBUGCALL;

    ERRIFNOTCONFIGED(s, S_OOPS);

    ad = (struct pluginDevice *) s;

    if ((ident = APC_read(ad->sptr, OID_IDENT, ASN_OCTET_STR)) == NULL) {
	LOG(PIL_CRIT, "%s: cannot read ident.", __FUNCTION__);
	return (S_ACCESS);
    }

    /* issue a warning if ident mismatches */
    for(i=DIMOF(APC_tested_ident) -1; i >=0 ; i--) {
      if (strcmp(ident, APC_tested_ident[i]) == 0) {
	 break;
      }
    }

    if (i<0) {
	LOG(PIL_WARN
        ,   "%s: module not tested with this hardware '%s'."
        ,   __FUNCTION__, ident);
    }
    /* status ok */
    return (S_OK);
}

/*
 * return the list of hosts configured for this device 
 */

static char **
apcmastersnmp_hostlist(StonithPlugin * s)
{
    char **hl;
    struct pluginDevice *ad;
    int j, h, num_outlets;
    char *outlet_name;
    char objname[MAX_STRING];

    DEBUGCALL;

    ERRIFNOTCONFIGED(s, NULL);

    ad = (struct pluginDevice *) s;

    /* allocate memory for array of up to NUM_OUTLETS strings */
    if ((hl = (char **)MALLOC((ad->num_outlets+1) * sizeof(char *))) == NULL) {
	LOG(PIL_CRIT, "%s: out of memory.", __FUNCTION__);
	return (NULL);
    }
    /* clear hostlist array */
    memset(hl, 0, (ad->num_outlets + 1) * sizeof(char *));
    num_outlets = 0;

    /* read NUM_OUTLETS values and put them into hostlist array */
    for (j = 0; j < ad->num_outlets; ++j) {

	/* prepare objname */
	snprintf(objname, MAX_STRING, OID_OUTLET_NAMES, j + 1);

	/* read outlet name */
	if ((outlet_name = APC_read(ad->sptr, objname, ASN_OCTET_STR)) ==
	    NULL) {
	    LOG(PIL_CRIT, "%s: cannot read name for outlet %d."
            ,   __FUNCTION__, j+1);
	    stonith_free_hostlist(hl);
	    hl = NULL;
	    return (hl);
	}

	/* Check whether the host is already listed */
	for (h = 0; h < num_outlets; ++h) {
		if (strcasecmp(hl[h],outlet_name) == 0)
			break;
	}

	if (h >= num_outlets) {
		/* put outletname in hostlist */
		if (Debug) {
	            LOG(PIL_DEBUG, "%s: added %s to hostlist."
		    ,   __FUNCTION__, outlet_name);
		}
		
		if ((hl[num_outlets] = STRDUP(outlet_name)) == NULL) {
		    LOG(PIL_CRIT, "%s: out of memory.", __FUNCTION__);
		    stonith_free_hostlist(hl);
		    hl = NULL;
		    return (hl);
		}
		strdown(hl[num_outlets]);
		num_outlets++;
	}
    }


    if (Debug) {
    	LOG(PIL_DEBUG, "%s: %d unique hosts connected to %d outlets."
	,   __FUNCTION__, num_outlets, j);
    }
    /* return list */
    return (hl);
}

/*
 * reset the host 
 */

static int
apcmastersnmp_reset_req(StonithPlugin * s, int request, const char *host)
{
    struct pluginDevice *ad;
    char objname[MAX_STRING];
    char value[MAX_STRING];
    char *outlet_name;
    int req_oid = OUTLET_REBOOT;
    int expect_state = OUTLET_ON;
    int i, h, num_outlets, outlet, reboot_duration, *state, bad_outlets;
    int outlets[8]; /* Assume that one node is connected to a 
		       maximum of 8 outlets */
    
    DEBUGCALL;

    ERRIFNOTCONFIGED(s, S_OOPS);

    ad = (struct pluginDevice *) s;

    num_outlets = 0;
    reboot_duration = 0;
    bad_outlets = 0;

    /* read max. as->num_outlets values */
    for (outlet = 1; outlet <= ad->num_outlets; outlet++) {

	/* prepare objname */
	snprintf(objname, MAX_STRING, OID_OUTLET_NAMES, outlet);

	/* read outlet name */
	if ((outlet_name = APC_read(ad->sptr, objname, ASN_OCTET_STR))
	==	NULL) {
	    LOG(PIL_CRIT, "%s: cannot read name for outlet %d."
            ,   __FUNCTION__, outlet);
	    return (S_ACCESS);
	}
	if (Debug) {
	    LOG(PIL_DEBUG, "%s: found outlet: %s.", __FUNCTION__, outlet_name);
	}
	
	/* found one */
	if (strcasecmp(outlet_name, host) == 0) {
		if (Debug) {
		    LOG(PIL_DEBUG, "%s: found %s at outlet %d."
		    ,   __FUNCTION__, host, outlet);
		}
		/* Check that the outlet is not administratively down */
		
		/* prepare objname */
		snprintf(objname, MAX_STRING, OID_OUTLET_STATE, outlet);

		/* get outlet's state */
		if ((state = APC_read(ad->sptr, objname, ASN_INTEGER)) == NULL) {
			LOG(PIL_CRIT
			,	"%s: cannot read state for outlet %d."
			,	__FUNCTION__, outlet);
			return (S_ACCESS);
		}

	        /* prepare oid */
	        snprintf(objname, MAX_STRING, OID_OUTLET_REBOOT_DURATION
		,	outlet);

	        /* read reboot duration of the port */
	        if ((state = APC_read(ad->sptr, objname, ASN_INTEGER))
		==	NULL) {
			LOG(PIL_CRIT
			,	"%s: cannot read reboot duration for outlet %d."
		       	,	__FUNCTION__, outlet);
			return (S_ACCESS);
	        }
	        if (num_outlets == 0) {
		   /* save the inital value of the first port */
		   reboot_duration = *state;
	        } else if (reboot_duration != *state) {
		  LOG(PIL_WARN, "%s: outlet %d has a different reboot duration!"
		  , __FUNCTION__, outlet);
	    	  if (reboot_duration < *state)
				reboot_duration = *state;
	        }
	    
		/* Ok, add it to the list of outlets to control */
		outlets[num_outlets]=outlet;
		num_outlets++;
	}
    }
    if (Debug) {
	    LOG(PIL_DEBUG, "%s: outlet: %i.", __FUNCTION__, outlet);
    }

    /* host not found in outlet names */
    if (num_outlets < 1) {
	LOG(PIL_CRIT, "%s: no active outlet for '%s'.", __FUNCTION__, host);
	return (S_BADHOST);
    }


	/* choose the OID for the stonith request */
	switch (request) {
		case ST_POWERON:
			req_oid = OUTLET_ON;
			expect_state = OUTLET_ON;
			break;
		case ST_POWEROFF:
			req_oid = OUTLET_OFF;
			expect_state = OUTLET_OFF;
			break;
		case ST_GENERIC_RESET:
			req_oid = OUTLET_REBOOT;
			expect_state = OUTLET_ON;
			break;
		default: break;
	}

    /* Turn them all off */

    for (outlet=outlets[0], i=0 ; i < num_outlets; i++, outlet = outlets[i]) {
	    /* prepare objname */
	    snprintf(objname, MAX_STRING, OID_OUTLET_COMMAND_PENDING, outlet);

	    /* are there pending commands ? */
	    if ((state = APC_read(ad->sptr, objname, ASN_INTEGER)) == NULL) {
		LOG(PIL_CRIT, "%s: cannot read pending commands for outlet %d." 
                ,	__FUNCTION__, outlet);
		return (S_ACCESS);
	    }

	    if (*state != OUTLET_NO_CMD_PEND) {
		LOG(PIL_CRIT, "%s: command pending.", __FUNCTION__);
		return (S_RESETFAIL);
	    }
	    
	    /* prepare objnames */
	    snprintf(objname, MAX_STRING, OID_OUTLET_STATE, outlet);
	    snprintf(value, MAX_STRING, "%i", req_oid);

	    /* send reboot cmd */
	    if (!APC_write(ad->sptr, objname, 'i', value)) {
		LOG(PIL_CRIT
		,	"%s: cannot send reboot command for outlet %d."
		,	__FUNCTION__, outlet);
		return (S_ACCESS);
	    }
    }
  
    /* wait max. 2*reboot_duration for all outlets to go back on */
    for (i = 0; i < reboot_duration << 1; i++) {
	    
	    sleep(1);

	    bad_outlets = 0;
	    for (outlet=outlets[0], h=0 ; h < num_outlets; h++, 
			    outlet = outlets[h]) {

		/* prepare objname of the first outlet */
		snprintf(objname, MAX_STRING, OID_OUTLET_STATE, outlet);
	    	/* get outlet's state */
		
		if ((state = APC_read(ad->sptr, objname, ASN_INTEGER))
		== NULL)			{
		    	LOG(PIL_CRIT
			,	"%s: cannot read state for outlet %d."
		   	,	__FUNCTION__, outlet);
			return (S_ACCESS);
		}

		if (*state != expect_state)
			bad_outlets++;
	     }
	     
	     if (bad_outlets == 0)
		return (S_OK);
    }
    
    if (bad_outlets == num_outlets) {
	    /* reset failed */
	    LOG(PIL_CRIT, "%s: stonith operation for '%s' failed."
	    ,	__FUNCTION__, host);
	    return (S_RESETFAIL);
    } else {
	    /* Not all outlets back on, but at least one; implies node was */
	    /* rebooted correctly */
	    LOG(PIL_WARN,"%s: Not all outlets in the expected state!"
	    ,	__FUNCTION__);
	    return (S_OK); 
    }
}

/*
 * Get the configuration parameter names.
 */

static const char * const *
apcmastersnmp_get_confignames(StonithPlugin * s)
{
	static const char * ret[] = {ST_IPADDR, ST_PORT, ST_COMMUNITY, NULL};
	return ret;
}

/*
 * Set the configuration parameters.
 */

static int
apcmastersnmp_set_config(StonithPlugin * s, StonithNVpair * list)
{
	struct pluginDevice* sd = (struct pluginDevice *)s;
	int	rc;
	int *	i;
	StonithNamesToGet	namestocopy [] =
	{	{ST_IPADDR,	NULL}
	,	{ST_PORT,	NULL}
	,	{ST_COMMUNITY,	NULL}
	,	{NULL,		NULL}
	};

	DEBUGCALL;
	ERRIFWRONGDEV(s,S_INVAL);
	if (sd->sp.isconfigured) {
		return S_OOPS;
	}

	if ((rc=OurImports->CopyAllValues(namestocopy, list)) != S_OK) {
		return rc;
	}
	sd->hostname = namestocopy[0].s_value;
	sd->port = atoi(namestocopy[1].s_value);
	PluginImports->mfree(namestocopy[1].s_value);
	sd->community = namestocopy[2].s_value;

        /* try to resolve the hostname/ip-address */
	if (gethostbyname(sd->hostname) != NULL) {
        	/* init snmp library */
		init_snmp("apcmastersnmp");

		/* now try to get a snmp session */
		if ((sd->sptr = APC_open(sd->hostname, sd->port, sd->community)) != NULL) {

			/* ok, get the number of outlets from the masterswitch */
			if ((i = APC_read(sd->sptr, OID_NUM_OUTLETS, ASN_INTEGER))
                    		== NULL) {
				LOG(PIL_CRIT
				, "%s: cannot read number of outlets."
				,       __FUNCTION__);
				return (S_ACCESS);
			}
			/* store the number of outlets */
			sd->num_outlets = *i;
			if (Debug) {
				LOG(PIL_DEBUG, "%s: number of outlets: %i."
				,       __FUNCTION__, sd->num_outlets );
			}

			/* Everything went well */
			return (S_OK);
		}else{
			LOG(PIL_CRIT, "%s: cannot create snmp session."
			,       __FUNCTION__);
		}
	}else{
		LOG(PIL_CRIT, "%s: cannot resolve hostname '%s', h_errno %d."
		,       __FUNCTION__, sd->hostname, h_errno);
	}

	/* not a valid config */
	return (S_BADCONFIG);
}

/*
 * get info about the stonith device 
 */

static const char *
apcmastersnmp_getinfo(StonithPlugin * s, int reqtype)
{
    struct pluginDevice *ad;
    const char *ret = NULL;

    DEBUGCALL;

    ERRIFWRONGDEV(s, NULL);

    ad = (struct pluginDevice *) s;

    switch (reqtype) {
	    case ST_DEVICEID:
		ret = ad->idinfo;
		break;

	    case ST_DEVICENAME:
		ret = ad->hostname;
		break;

	    case ST_DEVICEDESCR:
		ret = "APC MasterSwitch (via SNMP)\n"
		      "The APC MasterSwitch can accept multiple simultaneous SNMP clients";
		break;

	    case ST_DEVICEURL:
		ret = "http://www.apc.com/";
		break;

	    case ST_CONF_XML:		/* XML metadata */
		ret = apcmastersnmpXML;
		break;

	}
	return ret;
}


/*
 * APC StonithPlugin destructor... 
 */

static void
apcmastersnmp_destroy(StonithPlugin * s)
{
	struct pluginDevice *ad;

	DEBUGCALL;

	VOIDERRIFWRONGDEV(s);

	ad = (struct pluginDevice *) s;

	ad->pluginid = NOTpluginID;

	/* release snmp session */
	if (ad->sptr != NULL) {
		snmp_close(ad->sptr);
		ad->sptr = NULL;
	}

	/* reset defaults */
	if (ad->hostname != NULL) {
		PluginImports->mfree(ad->hostname);
		ad->hostname = NULL;
	}
	if (ad->community != NULL) {
		PluginImports->mfree(ad->community);
		ad->community = NULL;
	}
	ad->num_outlets = 0;

	PluginImports->mfree(ad);
}

/*
 * Create a new APC StonithPlugin device.  Too bad this function can't be
 * static 
 */

static StonithPlugin *
apcmastersnmp_new(const char *subplugin)
{
	struct pluginDevice *ad = ST_MALLOCT(struct pluginDevice);

	DEBUGCALL;

	/* no memory for stonith-object */
	if (ad == NULL) {
		LOG(PIL_CRIT, "%s: out of memory.", __FUNCTION__);
		return (NULL);
	}

	/* clear stonith-object */
	memset(ad, 0, sizeof(*ad));

	/* set defaults */
	ad->pluginid = pluginid;
	ad->sptr = NULL;
	ad->hostname = NULL;
	ad->community = NULL;
	ad->idinfo = DEVICE;
	ad->sp.s_ops = &apcmastersnmpOps;

	/* return the object */
	return (&(ad->sp));
}