/********************************************************************
NAME : EvaluateSlotDefaultValue
DESCRIPTION : Checks the default value against the slot
constraints and evaluates static default values
INPUTS : 1) The slot descriptor
2) The bitmap marking which facets were specified in
the original slot definition
RETURNS : TRUE if all OK, FALSE otherwise
SIDE EFFECTS : Static default value expressions deleted and
replaced with data object evaluation
NOTES : On errors, slot is marked as dynamix so that
DeleteSlots() will erase the slot expression
********************************************************************/
static intBool EvaluateSlotDefaultValue(
void *theEnv,
EXEC_STATUS,
SLOT_DESC *sd,
char *specbits)
{
DATA_OBJECT temp;
int oldce,olddcc,vCode;
/* ===================================================================
Slot default value expression is marked as dynamic until now so
that DeleteSlots() would erase in the event of an error. The delay
was so that the evaluation of a static default value could be
delayed until all the constraints were parsed.
=================================================================== */
if (TestBitMap(specbits,DEFAULT_DYNAMIC_BIT) == 0)
sd->dynamicDefault = 0;
if (sd->noDefault)
return(TRUE);
if (sd->dynamicDefault == 0)
{
if (TestBitMap(specbits,DEFAULT_BIT))
{
oldce = ExecutingConstruct(theEnv,execStatus);
SetExecutingConstruct(theEnv,execStatus,TRUE);
olddcc = EnvSetDynamicConstraintChecking(theEnv,execStatus,EnvGetStaticConstraintChecking(theEnv,execStatus));
vCode = EvaluateAndStoreInDataObject(theEnv,execStatus,(int) sd->multiple,
(EXPRESSION *) sd->defaultValue,&temp,TRUE);
if (vCode != FALSE)
vCode = ValidSlotValue(theEnv,execStatus,&temp,sd,NULL,"slot default value");
EnvSetDynamicConstraintChecking(theEnv,execStatus,olddcc);
SetExecutingConstruct(theEnv,execStatus,oldce);
if (vCode)
{
ExpressionDeinstall(theEnv,execStatus,(EXPRESSION *) sd->defaultValue);
ReturnPackedExpression(theEnv,execStatus,(EXPRESSION *) sd->defaultValue);
sd->defaultValue = (void *) get_struct(theEnv,execStatus,dataObject);
GenCopyMemory(DATA_OBJECT,1,sd->defaultValue,&temp);
ValueInstall(theEnv,execStatus,(DATA_OBJECT *) sd->defaultValue);
}
else
{
sd->dynamicDefault = 1;
return(FALSE);
}
}
else if (sd->defaultSpecified == 0)
{
sd->defaultValue = (void *) get_struct(theEnv,execStatus,dataObject);
DeriveDefaultFromConstraints(theEnv,execStatus,sd->constraint,
(DATA_OBJECT *) sd->defaultValue,(int) sd->multiple,TRUE);
ValueInstall(theEnv,execStatus,(DATA_OBJECT *) sd->defaultValue);
}
}
else if (EnvGetStaticConstraintChecking(theEnv,execStatus))
{
vCode = ConstraintCheckExpressionChain(theEnv,execStatus,(EXPRESSION *) sd->defaultValue,sd->constraint);
if (vCode != NO_VIOLATION)
{
PrintErrorID(theEnv,execStatus,"CSTRNCHK",1,FALSE);
EnvPrintRouter(theEnv,execStatus,WERROR,"Expression for ");
PrintSlot(theEnv,execStatus,WERROR,sd,NULL,"dynamic default value");
ConstraintViolationErrorMessage(theEnv,execStatus,NULL,NULL,0,0,NULL,0,
vCode,sd->constraint,FALSE);
return(FALSE);
}
}
return(TRUE);
}
/*********************************************************
NAME : CheckSlotReference
DESCRIPTION : Examines a ?self:<slot-name> reference
If the reference is a single-field or
global variable, checking and evaluation
is delayed until run-time. If the
reference is a symbol, this routine
verifies that the slot is a legal
slot for the reference (i.e., it exists
in the class to which the message-handler
is being attached, it is visible and it
is writable for write reference)
INPUTS : 1) A buffer holding the class
of the handler being parsed
2) The type of the slot reference
3) The value of the slot reference
4) A flag indicating if this is a read
or write access
5) Value expression for write
RETURNS : Class slot on success, NULL on errors
SIDE EFFECTS : Messages printed on errors.
NOTES : For static references, this function
insures that the slot is either
publicly visible or that the handler
is being attached to the same class in
which the private slot is defined.
*********************************************************/
static SLOT_DESC *CheckSlotReference(
void *theEnv,
DEFCLASS *theDefclass,
int theType,
void *theValue,
CLIPS_BOOLEAN writeFlag,
EXPRESSION *writeExpression)
{
int slotIndex;
SLOT_DESC *sd;
int vCode;
if (theType != SYMBOL)
{
PrintErrorID(theEnv,"MSGPSR",7,FALSE);
EnvPrintRouter(theEnv,WERROR,"Illegal value for ?self reference.\n");
return(NULL);
}
slotIndex = FindInstanceTemplateSlot(theEnv,theDefclass,(SYMBOL_HN *) theValue);
if (slotIndex == -1)
{
PrintErrorID(theEnv,"MSGPSR",6,FALSE);
EnvPrintRouter(theEnv,WERROR,"No such slot ");
EnvPrintRouter(theEnv,WERROR,ValueToString(theValue));
EnvPrintRouter(theEnv,WERROR," in class ");
EnvPrintRouter(theEnv,WERROR,EnvGetDefclassName(theEnv,(void *) theDefclass));
EnvPrintRouter(theEnv,WERROR," for ?self reference.\n");
return(NULL);
}
sd = theDefclass->instanceTemplate[slotIndex];
if ((sd->publicVisibility == 0) && (sd->cls != theDefclass))
{
SlotVisibilityViolationError(theEnv,sd,theDefclass);
return(NULL);
}
if (! writeFlag)
return(sd);
/* =================================================
If a slot is initialize-only, the WithinInit flag
still needs to be checked at run-time, for the
handler could be called out of the context of
an init.
================================================= */
if (sd->noWrite && (sd->initializeOnly == 0))
{
SlotAccessViolationError(theEnv,ValueToString(theValue),
FALSE,(void *) theDefclass);
return(NULL);
}
if (EnvGetStaticConstraintChecking(theEnv))
{
vCode = ConstraintCheckExpressionChain(theEnv,writeExpression,sd->constraint);
if (vCode != NO_VIOLATION)
{
PrintErrorID(theEnv,"CSTRNCHK",1,FALSE);
EnvPrintRouter(theEnv,WERROR,"Expression for ");
PrintSlot(theEnv,WERROR,sd,NULL,"direct slot write");
ConstraintViolationErrorMessage(theEnv,NULL,NULL,0,0,NULL,0,
vCode,sd->constraint,FALSE);
return(NULL);
}
}
return(sd);
}
/********************************************************************
NAME : EvaluateSlotDefaultValue
DESCRIPTION : Checks the default value against the slot
constraints and evaluates static default values
INPUTS : 1) The slot descriptor
2) The bitmap marking which facets were specified in
the original slot definition
RETURNS : True if all OK, false otherwise
SIDE EFFECTS : Static default value expressions deleted and
replaced with data object evaluation
NOTES : On errors, slot is marked as dynamix so that
DeleteSlots() will erase the slot expression
********************************************************************/
static bool EvaluateSlotDefaultValue(
Environment *theEnv,
SlotDescriptor *sd,
const char *specbits)
{
UDFValue temp;
bool oldce,olddcc, vPass;
ConstraintViolationType vCode;
/* ===================================================================
Slot default value expression is marked as dynamic until now so
that DeleteSlots() would erase in the event of an error. The delay
was so that the evaluation of a static default value could be
delayed until all the constraints were parsed.
=================================================================== */
if (! TestBitMap(specbits,DEFAULT_DYNAMIC_BIT))
sd->dynamicDefault = 0;
if (sd->noDefault)
return true;
if (sd->dynamicDefault == 0)
{
if (TestBitMap(specbits,DEFAULT_BIT))
{
oldce = ExecutingConstruct(theEnv);
SetExecutingConstruct(theEnv,true);
olddcc = SetDynamicConstraintChecking(theEnv,true);
vPass = EvaluateAndStoreInDataObject(theEnv,sd->multiple,
(Expression *) sd->defaultValue,&temp,true);
if (vPass != false)
vPass = (ValidSlotValue(theEnv,&temp,sd,NULL,"the 'default' facet") == PSE_NO_ERROR);
SetDynamicConstraintChecking(theEnv,olddcc);
SetExecutingConstruct(theEnv,oldce);
if (vPass)
{
ExpressionDeinstall(theEnv,(Expression *) sd->defaultValue);
ReturnPackedExpression(theEnv,(Expression *) sd->defaultValue);
sd->defaultValue = get_struct(theEnv,udfValue);
GenCopyMemory(UDFValue,1,sd->defaultValue,&temp);
RetainUDFV(theEnv,(UDFValue *) sd->defaultValue);
}
else
{
sd->dynamicDefault = 1;
return false;
}
}
else if (sd->defaultSpecified == 0)
{
sd->defaultValue = get_struct(theEnv,udfValue);
DeriveDefaultFromConstraints(theEnv,sd->constraint,
(UDFValue *) sd->defaultValue,sd->multiple,true);
RetainUDFV(theEnv,(UDFValue *) sd->defaultValue);
}
}
else
{
vCode = ConstraintCheckExpressionChain(theEnv,(Expression *) sd->defaultValue,sd->constraint);
if (vCode != NO_VIOLATION)
{
PrintErrorID(theEnv,"CSTRNCHK",1,false);
WriteString(theEnv,STDERR,"Expression for ");
PrintSlot(theEnv,STDERR,sd,NULL,"dynamic default value");
ConstraintViolationErrorMessage(theEnv,NULL,NULL,0,0,NULL,0,
vCode,sd->constraint,false);
return false;
}
}
return true;
}