/***********************************************************
NAME : ValidClassName
DESCRIPTION : Determines if a new class of the given
name can be defined in the current module
INPUTS : 1) The new class name
2) Buffer to hold class address
RETURNS : TRUE if OK, FALSE otherwise
SIDE EFFECTS : Error message printed if not OK
NOTES : GetConstructNameAndComment() (called before
this function) ensures that the defclass
name does not conflict with one from
another module
***********************************************************/
static intBool ValidClassName(
void *theEnv,
char *theClassName,
DEFCLASS **theDefclass)
{
*theDefclass = (DEFCLASS *) EnvFindDefclass(theEnv,theClassName);
if (*theDefclass != NULL)
{
/* ===================================
System classes (which are visible
in all modules) cannot be redefined
=================================== */
if ((*theDefclass)->system)
{
PrintErrorID(theEnv,"CLASSPSR",2,FALSE);
EnvPrintRouter(theEnv,WERROR,"Cannot redefine a predefined system class.\n");
return(FALSE);
}
/* ===============================================
A class in the current module can only be
redefined if it is not in use, e.g., instances,
generic function method restrictions, etc.
=============================================== */
if ((EnvIsDefclassDeletable(theEnv,(void *) *theDefclass) == FALSE) &&
(! ConstructData(theEnv)->CheckSyntaxMode))
{
PrintErrorID(theEnv,"CLASSPSR",3,FALSE);
EnvPrintRouter(theEnv,WERROR,EnvGetDefclassName(theEnv,(void *) *theDefclass));
EnvPrintRouter(theEnv,WERROR," class cannot be redefined while\n");
EnvPrintRouter(theEnv,WERROR," outstanding references to it still exist.\n");
return(FALSE);
}
}
return(TRUE);
}
/*****************************************************************************
NAME : AddClass
DESCRIPTION : Determines the precedence list of the new class.
If it is valid, the routine checks to see if the class
already exists. If it does not, all the subclass
links are made from the class's direct superclasses,
and the class is inserted in the hash table. If it
does, all sublclasses are deleted. An error will occur
if any instances of the class (direct or indirect) exist.
If all checks out, the old definition is replaced by the new.
INPUTS : The new class description
RETURNS : Nothing useful
SIDE EFFECTS : The class is deleted if there is an error.
NOTES : No change in the class graph state will occur
if there were any errors.
Assumes class is not busy!!!
*****************************************************************************/
static void AddClass(
void *theEnv,
DEFCLASS *cls)
{
DEFCLASS *ctmp;
#if DEBUGGING_FUNCTIONS
int oldTraceInstances = FALSE,
oldTraceSlots = FALSE;
#endif
/* ===============================================
If class does not already exist, insert and
form progeny links with all direct superclasses
=============================================== */
cls->hashTableIndex = HashClass(GetDefclassNamePointer((void *) cls));
ctmp = (DEFCLASS *) EnvFindDefclass(theEnv,EnvGetDefclassName(theEnv,(void *) cls));
if (ctmp != NULL)
{
#if DEBUGGING_FUNCTIONS
oldTraceInstances = ctmp->traceInstances;
oldTraceSlots = ctmp->traceSlots;
#endif
DeleteClassUAG(theEnv,ctmp);
}
PutClassInTable(theEnv,cls);
BuildSubclassLinks(theEnv,cls);
InstallClass(theEnv,cls,TRUE);
AddConstructToModule((struct constructHeader *) cls);
FormInstanceTemplate(theEnv,cls);
FormSlotNameMap(theEnv,cls);
AssignClassID(theEnv,cls);
#if DEBUGGING_FUNCTIONS
if (cls->abstract)
{
cls->traceInstances = FALSE;
cls->traceSlots = FALSE;
}
else
{
if (oldTraceInstances)
cls->traceInstances = TRUE;
if (oldTraceSlots)
cls->traceSlots = TRUE;
}
#endif
#if DEBUGGING_FUNCTIONS
if (EnvGetConserveMemory(theEnv) == FALSE)
SetDefclassPPForm((void *) cls,CopyPPBuffer(theEnv));
#endif
#if DEFMODULE_CONSTRUCT
/* =========================================
Create a bitmap indicating whether this
class is in scope or not for every module
========================================= */
cls->scopeMap = (BITMAP_HN *) CreateClassScopeMap(theEnv,cls);
#endif
/* ==============================================
Define get- and put- handlers for public slots
============================================== */
CreatePublicSlotMessageHandlers(theEnv,cls);
}
globle void *FindDefclass(
const char *classAndModuleName)
{
return EnvFindDefclass(GetCurrentEnvironment(),classAndModuleName);
}
globle intBool CheckAllowedClassesConstraint(
void *theEnv,
int type,
void *vPtr,
CONSTRAINT_RECORD *constraints)
{
#if OBJECT_SYSTEM
struct expr *tmpPtr;
INSTANCE_TYPE *ins;
DEFCLASS *insClass, *cmpClass;
/*=========================================*/
/* If the constraint record is NULL, there */
/* is no allowed-classes restriction. */
/*=========================================*/
if (constraints == NULL) return(TRUE);
/*======================================*/
/* The constraint is satisfied if there */
/* aren't any class restrictions. */
/*======================================*/
if (constraints->classList == NULL)
{ return(TRUE); }
/*==================================*/
/* Class restrictions only apply to */
/* instances and instance names. */
/*==================================*/
if ((type != INSTANCE_ADDRESS) && (type != INSTANCE_NAME))
{ return(TRUE); }
/*=============================================*/
/* If an instance name is specified, determine */
/* whether the instance exists. */
/*=============================================*/
if (type == INSTANCE_ADDRESS)
{ ins = (INSTANCE_TYPE *) vPtr; }
else
{ ins = FindInstanceBySymbol(theEnv,(SYMBOL_HN *) vPtr); }
if (ins == NULL)
{ return(FALSE); }
/*======================================================*/
/* Search through the class list to see if the instance */
/* belongs to one of the allowed classes in the list. */
/*======================================================*/
insClass = (DEFCLASS *) EnvGetInstanceClass(theEnv,ins);
for (tmpPtr = constraints->classList;
tmpPtr != NULL;
tmpPtr = tmpPtr->nextArg)
{
cmpClass = (DEFCLASS *) EnvFindDefclass(theEnv,ValueToString(tmpPtr->value));
if (cmpClass == NULL) continue;
if (cmpClass == insClass) return(TRUE);
if (EnvSubclassP(theEnv,insClass,cmpClass)) return(TRUE);
}
/*=========================================================*/
/* If a parent class wasn't found in the list, then return */
/* FALSE because the constraint has been violated. */
/*=========================================================*/
return(FALSE);
#else
#if MAC_XCD
#pragma unused(theEnv)
#pragma unused(type)
#pragma unused(vPtr)
#pragma unused(constraints)
#endif
return(TRUE);
#endif
}
