/*--------------------------------------------------------------------------
 podunk_rr.c - code to extend UCD-SNMP agent for PODUNK-RR-MIB
 Compiled inside the ucd-snmp source tree 

 To extend this MIB with another variable in an existing table or row,
 no editing of this file is required; just run mib2h.pl again and recompile.
 To extend this MIB with another table or row (or scalar row),
 edit this file to add a section for that table or row.  
 (Yeah, that should be automated by mib2h.pl.  So FIXME.)
--------------------------------------------------------------------------*/

/* I'd rather include the following two .h files within fsubagent_utils.h
 * and podunk_rr.h, which need types they define, but doing that seems to 
 * cause problems (config.h doesn't protect itself against multiple inclusion).
 * Looks like standard practice in ucd-snmp code is that all .c files
 * first include these two .h files, and other .h files assume those have
 * already been included?
 */
#include "config.h"
#include "mibincl.h"

/* prototype for this module's public entry point */
#include "podunk_rr.h"

/* generic helper stuff from ucd-snmp */
#include "util_funcs.h"

/* specific helper stuff for fsubagent */
#include "dprint.h"
#include "fsubagent_utils.h"

/* everything below this point is more or less custom-coded for
 * the PODUNK-RR-MIB demo, but could probably be generated by
 * mib2h.pl, it's that predictable.
 */

/* Output of mib2h.pl < PODUNK-RR-MIB.txt */
#include "podunk_rr_mib.h"

/* system includes come last, to prove above .h files stand on their own */
#include <limits.h>
#include <stddef.h>
#include <stdio.h>
#include <time.h>

/* data file written by application being monitored, read by this module */
#define SHARED_FNAME "podunk_rr.fsa"

/* um, should come from mib2h.pl but doesn't */
#define ENTERPRISES_OID 1,3,6,1,4,1

/* Each row or table needs a pointer, a wrapper function with prototype,
 * an init function, and a macro defining all its variables.
 * The wrapper functions that just supply the missing row or array pointer,
 * then call the real accessor.
 * The init function for this module will invoke PODUNK_RR_INIT,
 * a macro generated by mib2h.pl that calls all the table/row init functions.
 */

/*---------------- begin table/row definitions ---------------*/

/*------ fleetStatus (a scalar row) -------*/

static fsubagentRow *g_row_fleetStatus = NULL;

static FindVarMethod handle_fleetStatus;

static unsigned char *handle_fleetStatus(
	struct variable *vp, 
	oid				*name, 
	size_t			*length, 
	int				exact, 
	size_t			*var_len, 
	WriteMethod	**write_method)
{
	DPRINT(("handle_fleetStatus:\n"));
	return fsubagent_utils_getFromScalarRow(g_row_fleetStatus, 
		vp, name, length, exact, var_len, write_method);
}

static void init_fleetStatus()
{
	static const struct variable2 vars_fleetStatus[] = {
		PODUNK_RR_VARS_fleetStatus
	};

	/* the full OID */
	static oid x_oid_fleetStatus[]={
		ENTERPRISES_OID, PODUNK_RR_podunk,PODUNK_RR_fleet,
		PODUNK_RR_fleetStatus};

	/* just the part of the OID below this module's root */
	static int oid_fleetStatus[] = {
		PODUNK_RR_fleetStatus, fsubagent_END};

	g_row_fleetStatus = fsubagent_createScalarRow(fsubagent_utils_subagent, oid_fleetStatus, PODUNK_RR_fleetStatus_FORMAT);

	REGISTER_MIB("podunk_rr-fleetStatus", vars_fleetStatus, variable2, x_oid_fleetStatus);
}


/*------ trainEntry -------*/

static fsubagentArray *g_arr_trainEntry = NULL;

static FindVarMethod handle_trainEntry;

static unsigned char *
handle_trainEntry(struct variable *vp, 
	oid				*name, 
	size_t			*length, 
	int				exact, 
	size_t			*var_len, 
	WriteMethod	**write_method)
{
	DPRINT(("handle_trainEntry:\n"));
	return fsubagent_utils_getFromTable1(g_arr_trainEntry, 
		vp, name, length, exact, var_len, write_method);
}

static void init_trainEntry()
{
	static const struct variable2 vars_trainEntry[] = {
		PODUNK_RR_VARS_trainEntry
	};

	static oid x_oid_trainEntry[]={
		ENTERPRISES_OID, PODUNK_RR_podunk, PODUNK_RR_fleet,
		PODUNK_RR_trainTable, PODUNK_RR_trainEntry};

	static int oid_trainEntry[] = {
		PODUNK_RR_trainTable, PODUNK_RR_trainEntry, fsubagent_END};

	g_arr_trainEntry = fsubagent_createArray(fsubagent_utils_subagent, oid_trainEntry, PODUNK_RR_trainEntry_FORMAT);

	REGISTER_MIB("podunk_rr-trainEntry", vars_trainEntry, variable2, x_oid_trainEntry);
}

/*------ carEntry -------*/

static fsubagentArray2 *g_arr2_carEntry = NULL;

static FindVarMethod handle_carEntry;

static unsigned char *handle_carEntry(
	struct variable *vp, 
	oid				*name, 
	size_t			*length, 
	int				exact, 
	size_t			*var_len, 
	WriteMethod	**write_method)
{
	DPRINT(("handle_carEntry:\n"));
	return fsubagent_utils_getFromTable2(g_arr2_carEntry, 
		vp, name, length, exact, var_len, write_method);
}

static void init_carEntry()
{
	static const struct variable2 vars_carEntry[] = {
		PODUNK_RR_VARS_carEntry
	};

	static oid x_oid_carEntry[]=
		{ENTERPRISES_OID, PODUNK_RR_podunk, PODUNK_RR_fleet,
		PODUNK_RR_carTable, PODUNK_RR_carEntry};

	static int oid_carEntry[] =
		{PODUNK_RR_carTable, PODUNK_RR_carEntry, fsubagent_END};

	g_arr2_carEntry = fsubagent_createArray2(fsubagent_utils_subagent, oid_carEntry, PODUNK_RR_carEntry_FORMAT);

	REGISTER_MIB("podunk_rr-carEntry", vars_carEntry, variable2, x_oid_carEntry);
}

/*---------------- end table/row definitions ---------------*/

/* Event handler for snmpd configuration changes.
 * May be called during startup of snmpd.
 */
void onRefreshTime(const char *name, char *value)
{
	fsubagent_utils_cacheSeconds = atoi(value);
	DPRINT(("onRefreshTime: setting fsubagent_utils_cacheSeconds to %d\n", 
			fsubagent_utils_cacheSeconds));
}

/*	
 * Initialization routine called by snmpd when it starts up.
 * The name of this function must be init_ followed by the carname of this 
 * .c car.
 * Don't confuse this with the init_ routines above, which are private
 * to this module.
*/

void init_podunk_rr(void) 
{
	/* Get ready to handle snmpd.conf config file settings */
	snmpd_register_config_handler("cacheSeconds", 
		onRefreshTime, NULL, "How many seconds to cache " SHARED_FNAME);

	/* Create the object that will read the MIB variables from disk */
	fsubagent_utils_subagent = fsubagent_new();

	/* Initialize all the rows & tables by calling the init_* routines
	 * defined above.
	 * This is a macro generated by mib2h.pl that calls init_xxx for
	 * every table and scalar row 'xxx' in the MIB.
	 * The linker will remind us if we forget to hand-code an init routine.
	 */
	PODUNK_RR_INIT;

	DPRINT(("init_podunk_rr: filename %s\n", SHARED_FNAME));
	fsubagent_setFilename(fsubagent_utils_subagent, SHARED_FNAME);

	/* Load the data file for the first time. */
	fsubagent_utils_update(TRUE);
}