statbufc.c

嵌入式RMON,RMON为Remote monitor的缩写,基于SNMP为网络提供主动监控及错误告警,智能交换路由必备协议

/* Beholder RMON ethernet network monitor,Copyright (C) 1993 DNPAP group */
/* See file COPYING 'GNU General Public Licence' for copyright details   */
#include <math.h>
#include <config.h>
#include <memory.h>
#include <maxmem.h>
#include <mibrqs.h>
#include <mibsup.h>
#include <sysmib.h>
#include <dmath.h>

#include "statbufd.h"
#include "statbufe.h"
#include "statbufc.h"


IMPORT BOOLEAN BeholderStrictRMON;


SHORT StatBufMaxNrEntries = 100;


static VOID StatBufCallback(TIMER_DESCR *timer, ULONG now, VOID *param);
static WORD StatBufSample(LONG *id, WORD idlen, LONG *value, SNMP_OBJECT *obj);

static BOOLEAN StatBufAddValue(StatBufControl *statbufcontrol, LONG value, ULONG now);
static BOOLEAN StatBufCalcStats(StatBufControl *statbufcontrol);



BOOLEAN StatBufConfigInit(VOID)
{
	ConfigGetShort("beholder.statbuf.maxnrentries", &StatBufMaxNrEntries);

	if (StatBufMaxNrEntries < 2)
    {
        DnpapMessage(DMC_WARNING, STATBUF_MAX, "statbufcontrol: beholder.statbuf.maxnrentries < 2, setting it to 2");
        StatBufMaxNrEntries = 2;
    }

	return TRUE;
}


BOOLEAN StatBufCInit(StatBufControl *statbufcontrol)
{
    statbufcontrol->Variable[0] = 0;
    statbufcontrol->Variable[1] = 0;
    statbufcontrol->VariableLen = 2;

    statbufcontrol->RequestedSize = 10;
    statbufcontrol->GrantedSize = 0;
    statbufcontrol->Interval = 100;
    statbufcontrol->SampleType = STATBUF_ABSOLUTE;
    statbufcontrol->FullStatus = STATBUF_SPACE;
    statbufcontrol->FullAction = STATBUF_LOCK;
    statbufcontrol->Average = 0;
    statbufcontrol->Deviation = 0;

    statbufcontrol->Owner[0] = '\0';
    statbufcontrol->OwnerLen = 0;
    statbufcontrol->Status = SNMP_INVALID;

    statbufcontrol->Buffer = NULL;

    statbufcontrol->BufferAllocated = 0;
    statbufcontrol->BufferPos = 0;
    statbufcontrol->BufferWrapped = FALSE;

    statbufcontrol->Timer = NULL;

    statbufcontrol->GrantedSize = LongMin(MemoryGetAvail(), MemoryGetMaxChunk())/sizeof(StatBuf);
    if (statbufcontrol->GrantedSize > LongMin(statbufcontrol->RequestedSize, StatBufMaxNrEntries))
        statbufcontrol->GrantedSize = LongMin(statbufcontrol->RequestedSize, StatBufMaxNrEntries);
    if ((statbufcontrol->Buffer = NewStatBuf(statbufcontrol->GrantedSize)) == NULL)
    {
        statbufcontrol->GrantedSize = 0;
        statbufcontrol->BufferAllocated = 0;
        statbufcontrol->BufferPos = 0;
        statbufcontrol->BufferWrapped = FALSE;
    }
    else
    {
        statbufcontrol->BufferAllocated = statbufcontrol->GrantedSize;
        statbufcontrol->BufferPos = 0;
        statbufcontrol->BufferWrapped = FALSE;
    }

	BooleanSetAllTrue(statbufcontrol->ObjectSet);
	BooleanSetFalse(statbufcontrol->ObjectSet, STATBUF_BOOLEAN_VARIABLE);
	BooleanSetFalse(statbufcontrol->ObjectSet, STATBUF_BOOLEAN_OWNER);

    return TRUE;
}


BOOLEAN StatBufCStart(StatBufControl *statbufcontrol)
{
LONG value;
SNMP_OBJECT obj = { SNMP_PDU_GET, { 0, 0 }, 2, SNMP_INTEGER };

	if (BeholderStrictRMON && !BooleanCheckAllTrue(statbufcontrol->ObjectSet))
		return FALSE;

    if (statbufcontrol->SampleType == STATBUF_DELTA)
    {
        if (StatBufSample(statbufcontrol->Variable, statbufcontrol->VariableLen, &value, &obj) == SNMP_NOERROR)
        {
            statbufcontrol->PrevValue = value;
        }
    }

    if ((statbufcontrol->Timer = TimerRegister(StatBufCallback, (VOID*)statbufcontrol, statbufcontrol->Interval*10, TIMER_FOREVER, TIMER_TYPE_SKIP)) == NULL)
        return FALSE;

    return TRUE;
}


BOOLEAN StatBufCStop(StatBufControl *statbufcontrol)
{
    DelStatBuf(statbufcontrol->Buffer);

    TimerRemove(statbufcontrol->Timer);

    return TRUE;
}



VOID StatBufCallback(TIMER_DESCR *timer, ULONG now, VOID *param)
{
SNMP_OBJECT obj = { SNMP_PDU_GET, { 0, 0 }, 2, SNMP_INTEGER };
LONG value = 0, v = 0;
StatBufControl *statbufcontrol = param;

    if (StatBufSample(statbufcontrol->Variable, statbufcontrol->VariableLen, &value, &obj) == SNMP_NOERROR)
    {
        if (statbufcontrol->SampleType == STATBUF_DELTA)
        {
            v = value-statbufcontrol->PrevValue;
            statbufcontrol->PrevValue = value;
        }
        else
        if (statbufcontrol->SampleType == STATBUF_ABSOLUTE)
        {
            v = value;
        }
        if (StatBufAddValue(statbufcontrol, v, now) == TRUE)
            StatBufCalcStats(statbufcontrol);
    }
}


WORD StatBufSample(LONG *id, WORD idlen, LONG *value, SNMP_OBJECT *obj)
{
    obj->Request = SNMP_PDU_GET;
	memcpy(obj->Id, id, (obj->IdLen = idlen)*sizeof(id[0]));
	if (MibRequest(obj) != SNMP_NOERROR)
        return SNMP_NOSUCHNAME;
	
	switch (obj->Type)
	{
	case SNMP_INTEGER:
	case SNMP_COUNTER:
	case SNMP_GAUGE:
	case SNMP_TIMETICKS:
		*value = obj->Syntax.LngInt;
		return SNMP_NOERROR;
	default:
		return SNMP_BADVALUE;
	}
}


BOOLEAN StatBufAddValue(StatBufControl *statbufcontrol, LONG value, ULONG now)
{
StatBuf *entries, *entry;

    if (statbufcontrol->BufferWrapped == FALSE &&
        statbufcontrol->GrantedSize < statbufcontrol->RequestedSize &&
        statbufcontrol->GrantedSize < StatBufMaxNrEntries)
    {
        if ((entries = ReNewStatBuf(statbufcontrol->Buffer, statbufcontrol->GrantedSize+1, statbufcontrol->BufferAllocated, StatBufMaxNrEntries)) != NULL)
        {
            statbufcontrol->FullStatus = STATBUF_SPACE;
            statbufcontrol->Buffer = entries;
            statbufcontrol->BufferAllocated = ++statbufcontrol->GrantedSize;
        }
    }

    if (statbufcontrol->BufferAllocated == 0)
    {
        DnpapMessage(DMC_ERROR, STATBUF_NOENTRIES, "history: could not allocate any entries");
        return FALSE;
    }

    if (statbufcontrol->BufferPos == statbufcontrol->GrantedSize)
    {
        statbufcontrol->FullStatus = STATBUF_FULL;
        if (statbufcontrol->FullAction == STATBUF_LOCK)
            return FALSE;
        statbufcontrol->BufferPos = 0;
        statbufcontrol->BufferWrapped = TRUE;
    }

    if (statbufcontrol->FullStatus == STATBUF_FULL && statbufcontrol->FullAction == STATBUF_LOCK)
        return FALSE;

    entry = &statbufcontrol->Buffer[statbufcontrol->BufferPos++];

    entry->Time = now;
    entry->Value = value;

    return TRUE;
}


BOOLEAN StatBufCalcStats(StatBufControl *statbufcontrol)
{
LONG i, n;
LONG value;
FLOAT average = 0, deviation = 0;

    if (statbufcontrol->GrantedSize > 0)
    {
        if (statbufcontrol->BufferWrapped == FALSE)
            n = statbufcontrol->BufferPos;
        else
            n = statbufcontrol->GrantedSize;

        for (i = 0; i < n; i++)
        {
            value = statbufcontrol->Buffer[i].Value;
            average += value;
            deviation += value*value;
        }

        average /= statbufcontrol->GrantedSize;
        deviation /= statbufcontrol->GrantedSize;
        deviation -= average*average;
        deviation = (FLOAT)sqrt(deviation);
    }

    statbufcontrol->Average = (LONG)(average*1000);
    statbufcontrol->Deviation = (LONG)(deviation*1000);

    return TRUE;
}


StatBuf* StatBufSearch(StatBufControl *statbufcontrol, SNMP_OBJECT *obj, WORD idlen)
{
    if (obj->Id[idlen+1] > statbufcontrol->GrantedSize ||
        (statbufcontrol->BufferWrapped == FALSE && obj->Id[idlen+1] > statbufcontrol->BufferPos))
        return NULL;
    else
        if (statbufcontrol->BufferWrapped == FALSE)
            return &statbufcontrol->Buffer[obj->Id[idlen+1]-1];
        else
            return &statbufcontrol->Buffer[(statbufcontrol->BufferPos+obj->Id[idlen+1]-1) % statbufcontrol->GrantedSize];
    return NULL;
}


StatBuf* NewStatBuf(LONG n)
{
	return DnpapMalloc(n*sizeof(StatBuf));
}


StatBuf* ReNewStatBuf(StatBuf *p, LONG n, LONG oldn, LONG maxn)
{
LONG m, mold;

	if (n > maxn || ((LONG)n*sizeof(StatBuf) > MemoryGetMaxChunk()))
		return NULL;
    m = ((n-1)/MINALLOCENTRIES)*MINALLOCENTRIES+MINALLOCENTRIES;
    mold = ((oldn-1)/MINALLOCENTRIES)*MINALLOCENTRIES+MINALLOCENTRIES;
    if (p == NULL || LongAbs(m-mold) >= MINALLOCENTRIES)
    {
        return DnpapRealloc(p, LongMin(m, maxn)*sizeof(StatBuf));
    }        
    else
        return p;
}


VOID DelStatBuf(StatBuf *p)
{
    DnpapFree(p);
}


StatBufControl* NewStatBufControl(LONG n)
{
	return DnpapMalloc(n*sizeof(StatBufControl));
}


VOID DelStatBufControl(StatBufControl *p)
{
    DnpapFree(p);
}