/* vm.c - the arithmetic stack of a virtual machine.
*
* Module begun 2008-02-22 by Rainer Gerhards
*
* Copyright 2008 Rainer Gerhards and Adiscon GmbH.
*
* This file is part of rsyslog.
*
* Rsyslog 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 3 of the License, or
* (at your option) any later version.
*
* Rsyslog 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 Rsyslog. If not, see .
*
* A copy of the GPL can be found in the file "COPYING" in this distribution.
*/
#include "config.h"
#include
#include
#include "rsyslog.h"
#include "obj.h"
#include "vm.h"
#include "stringbuf.h"
/* static data */
DEFobjStaticHelpers
DEFobjCurrIf(vmstk)
DEFobjCurrIf(var)
/* ------------------------------ instruction set implementation ------------------------------ *
* The following functions implement the VM's instruction set.
*/
#define BEGINop(instruction) \
static rsRetVal op##instruction(vm_t *pThis, __attribute__((unused)) vmop_t *pOp) \
{ \
DEFiRet;
#define CODESTARTop(instruction) \
ISOBJ_TYPE_assert(pThis, vm);
#define ENDop(instruction) \
RETiRet; \
}
/* code generator for boolean operations */
#define BOOLOP(name, OPERATION) \
BEGINop(name) /* remember to set the instruction also in the ENDop macro! */ \
var_t *operand1; \
var_t *operand2; \
CODESTARTop(name) \
vmstk.PopBool(pThis->pStk, &operand1); \
vmstk.PopBool(pThis->pStk, &operand2); \
if(operand1->val.num OPERATION operand2->val.num) { \
CHKiRet(var.SetNumber(operand1, 1)); \
} else { \
CHKiRet(var.SetNumber(operand1, 0)); \
} \
vmstk.Push(pThis->pStk, operand1); /* result */ \
var.Destruct(&operand2); /* no longer needed */ \
finalize_it: \
ENDop(name)
BOOLOP(OR, ||)
BOOLOP(AND, &&)
#undef BOOLOP
/* code generator for compare operations */
#define BEGINCMPOP(name) \
BEGINop(name) \
var_t *operand1; \
var_t *operand2; \
int bRes; \
CODESTARTop(name) \
CHKiRet(vmstk.Pop2CommOp(pThis->pStk, &operand1, &operand2)); \
/* data types are equal (so we look only at operand1), but we must \
* check which type we have to deal with... \
*/ \
switch(operand1->varType) {
#define ENDCMPOP(name) \
default: \
bRes = 0; /* we do not abort just so that we have a value. TODO: reconsider */ \
break; \
} \
\
/* we have a result, so let's push it */ \
var.SetNumber(operand1, bRes); \
vmstk.Push(pThis->pStk, operand1); /* result */ \
var.Destruct(&operand2); /* no longer needed */ \
finalize_it: \
ENDop(name)
BEGINCMPOP(CMP_EQ) /* remember to change the name also in the END macro! */
case VARTYPE_NUMBER:
bRes = operand1->val.num == operand2->val.num;
break;
case VARTYPE_STR:
bRes = !rsCStrCStrCmp(operand1->val.pStr, operand2->val.pStr);
break;
ENDCMPOP(CMP_EQ)
BEGINCMPOP(CMP_NEQ) /* remember to change the name also in the END macro! */
case VARTYPE_NUMBER:
bRes = operand1->val.num != operand2->val.num;
break;
case VARTYPE_STR:
bRes = rsCStrCStrCmp(operand1->val.pStr, operand2->val.pStr);
break;
ENDCMPOP(CMP_EQ)
BEGINCMPOP(CMP_LT) /* remember to change the name also in the END macro! */
case VARTYPE_NUMBER:
bRes = operand1->val.num < operand2->val.num;
break;
case VARTYPE_STR:
bRes = rsCStrCStrCmp(operand1->val.pStr, operand2->val.pStr) < 0;
break;
ENDCMPOP(CMP_LT)
BEGINCMPOP(CMP_GT) /* remember to change the name also in the END macro! */
case VARTYPE_NUMBER:
bRes = operand1->val.num > operand2->val.num;
break;
case VARTYPE_STR:
bRes = rsCStrCStrCmp(operand1->val.pStr, operand2->val.pStr) > 0;
break;
ENDCMPOP(CMP_GT)
BEGINCMPOP(CMP_LTEQ) /* remember to change the name also in the END macro! */
case VARTYPE_NUMBER:
bRes = operand1->val.num <= operand2->val.num;
break;
case VARTYPE_STR:
bRes = rsCStrCStrCmp(operand1->val.pStr, operand2->val.pStr) <= 0;
break;
ENDCMPOP(CMP_LTEQ)
BEGINCMPOP(CMP_GTEQ) /* remember to change the name also in the END macro! */
case VARTYPE_NUMBER:
bRes = operand1->val.num >= operand2->val.num;
break;
case VARTYPE_STR:
bRes = rsCStrCStrCmp(operand1->val.pStr, operand2->val.pStr) >= 0;
break;
ENDCMPOP(CMP_GTEQ)
#undef BEGINCMPOP
#undef ENDCMPOP
/* end regular compare operations */
/* comare operations that work on strings, only */
BEGINop(CMP_CONTAINS) /* remember to set the instruction also in the ENDop macro! */
var_t *operand1;
var_t *operand2;
int bRes;
CODESTARTop(CMP_CONTAINS)
/* operand2 is on top of stack, so needs to be popped first */
vmstk.PopString(pThis->pStk, &operand2);
vmstk.PopString(pThis->pStk, &operand1);
/* TODO: extend cstr class so that it supports location of cstr inside cstr */
bRes = (rsCStrLocateInSzStr(operand2->val.pStr, rsCStrGetSzStr(operand1->val.pStr)) == -1) ? 0 : 1;
/* we have a result, so let's push it */
var.SetNumber(operand1, bRes);
vmstk.Push(pThis->pStk, operand1); /* result */
var.Destruct(&operand2); /* no longer needed */
ENDop(CMP_CONTAINS)
/* end comare operations that work on strings, only */
BEGINop(POP) /* remember to set the instruction also in the ENDop macro! */
CODESTARTop(POP)
/* TODO: implement */
ENDop(POP)
BEGINop(PUSHCONSTANT) /* remember to set the instruction also in the ENDop macro! */
CODESTARTop(PUSHCONSTANT)
vmstk.Push(pThis->pStk, pOp->operand.pVar);
ENDop(PUSHCONSTANT)
/* ------------------------------ end instruction set implementation ------------------------------ */
/* Standard-Constructor
*/
BEGINobjConstruct(vm) /* be sure to specify the object type also in END macro! */
ENDobjConstruct(vm)
/* ConstructionFinalizer
* rgerhards, 2008-01-09
*/
static rsRetVal
vmConstructFinalize(vm_t __attribute__((unused)) *pThis)
{
DEFiRet;
ISOBJ_TYPE_assert(pThis, vm);
RETiRet;
}
/* destructor for the vm object */
BEGINobjDestruct(vm) /* be sure to specify the object type also in END and CODESTART macros! */
CODESTARTobjDestruct(vm)
ENDobjDestruct(vm)
/* debugprint for the vm object */
BEGINobjDebugPrint(vm) /* be sure to specify the object type also in END and CODESTART macros! */
CODESTARTobjDebugPrint(vm)
dbgoprint((obj_t*) pThis, "rsyslog virtual machine, currently no state info available\n");
ENDobjDebugPrint(vm)
/* execute a program
*/
static rsRetVal
execProg(vm_t *pThis, vmprg_t *pProg)
{
DEFiRet;
vmop_t *pCurrOp; /* virtual instruction pointer */
ISOBJ_TYPE_assert(pThis, vm);
ISOBJ_TYPE_assert(pProg, vmprg);
#define doOP(OP) case opcode_##OP: CHKiRet(op##OP(pThis, pCurrOp)); break
pCurrOp = pProg->vmopRoot; /* TODO: do this via a method! */
while(pCurrOp != NULL && pCurrOp->opcode != opcode_END_PROG) {
switch(pCurrOp->opcode) {
doOP(OR);
doOP(AND);
doOP(CMP_EQ);
doOP(CMP_NEQ);
doOP(CMP_LT);
doOP(CMP_GT);
doOP(CMP_LTEQ);
doOP(CMP_GTEQ);
doOP(CMP_CONTAINS);
// TODO: implement: doOP(CMP_STARTSWITH);
doOP(POP);
doOP(PUSHCONSTANT);
default:
ABORT_FINALIZE(RS_RET_INVALID_VMOP);
dbgoprint((obj_t*) pThis, "invalid instruction %d in vmprg\n", pCurrOp->opcode);
break;
}
/* so far, we have plain sequential execution, so on to next... */
pCurrOp = pCurrOp->pNext;
}
#undef doOP
/* if we reach this point, our program has intintionally terminated
* (no error state).
*/
finalize_it:
RETiRet;
}
/* queryInterface function
* rgerhards, 2008-02-21
*/
BEGINobjQueryInterface(vm)
CODESTARTobjQueryInterface(vm)
if(pIf->ifVersion != vmCURR_IF_VERSION) { /* check for current version, increment on each change */
ABORT_FINALIZE(RS_RET_INTERFACE_NOT_SUPPORTED);
}
/* ok, we have the right interface, so let's fill it
* Please note that we may also do some backwards-compatibility
* work here (if we can support an older interface version - that,
* of course, also affects the "if" above).
*/
pIf->oID = OBJvm;
pIf->Construct = vmConstruct;
pIf->ConstructFinalize = vmConstructFinalize;
pIf->Destruct = vmDestruct;
pIf->DebugPrint = vmDebugPrint;
pIf->ExecProg = execProg;
finalize_it:
ENDobjQueryInterface(vm)
/* Initialize the vm class. Must be called as the very first method
* before anything else is called inside this class.
* rgerhards, 2008-02-19
*/
BEGINObjClassInit(vm, 1) /* class, version */
/* request objects we use */
CHKiRet(objUse(vmstk));
CHKiRet(objUse(var));
/* set our own handlers */
OBJSetMethodHandler(objMethod_DEBUGPRINT, vmDebugPrint);
OBJSetMethodHandler(objMethod_CONSTRUCTION_FINALIZER, vmConstructFinalize);
ENDObjClassInit(vm)
/* vi:set ai:
*/