Tcl Source Code

	return 0;
    }

    /*
     * We must delete this command, even though both traces and delete procs
     * may try to avoid this (renaming the command etc). Also traces and
     * delete procs may try to delete the command themselves. This flag
     * declares that a delete is in progress and that recursive deletes should
     * be ignored.
     */

    cmdPtr->flags |= CMD_IS_DELETED;

    /*

	return TCL_ERROR;
    }

    if (!(iPtr->flags & RAND_SEED_INITIALIZED)) {
	iPtr->flags |= RAND_SEED_INITIALIZED;

	/*
	 * To ensure different seeds in different threads (bug #416643), 
	 * take into consideration the thread this interp is running in.

	 */

	iPtr->randSeed = TclpGetClicks() + (PTR2INT(Tcl_GetCurrentThread())<<12);

	/*
	 * Make sure 1 <= randSeed <= (2^31) - 2. See below.
	 */

    corPtr->callerEEPtr = iPtr->execEnvPtr;
    RESTORE_CONTEXT(corPtr->running);
    iPtr->execEnvPtr = corPtr->eePtr;

    TclNRAddCallback(interp, NRCoroutineExitCallback, corPtr,
	    NULL, NULL, NULL);

    /* ensure that the command is looked up in the correct namespace */
    iPtr->lookupNsPtr = lookupNsPtr;
    Tcl_NREvalObj(interp, Tcl_NewListObj(objc-2, objv+2), 0);
    iPtr->numLevels--;

    SAVE_CONTEXT(corPtr->running);
    RESTORE_CONTEXT(corPtr->caller);
    iPtr->execEnvPtr = corPtr->callerEEPtr;

		&driveNameLen, &driveName) == TCL_PATH_ABSOLUTE) {
	    pathPrefix = driveName;
	    tail += driveNameLen;
	}
    }

    /*
     * To process a [glob] invocation, this function may be called multiple
     * times. Each time, the previously discovered filenames are in the
     * interpreter result. We stash that away here so the result is free for
     * error messsages.
     */

    savedResultObj = Tcl_GetObjResult(interp);
    Tcl_IncrRefCount(savedResultObj);

    }

    /*
     * The namespace is only deleted if it hasn't already been deleted. [Bug
     * 2950259]
     */

    if (oPtr->namespacePtr && ((Namespace *) oPtr->namespacePtr)->earlyDeleteProc != NULL) {
	Tcl_DeleteNamespace(oPtr->namespacePtr);
    }
    if (oPtr->classPtr) {
	DelRef(oPtr->classPtr);
    }
    DelRef(fPtr->classCls->thisPtr);
    DelRef(fPtr->objectCls->thisPtr);

				 * being deleted. */
{
    Object *oPtr = clientData;
    FOREACH_HASH_DECLS;
    Class *clsPtr = oPtr->classPtr, *mixinPtr;
    Method *mPtr;
    Tcl_Obj *filterObj, *variableObj;
    int deleteAlreadyInProgress = 0, i;

    /*
     * Instruct everyone to no longer use any allocated fields of the object.
     * Also delete the commands that refer to the object at this point (if
     * they still exist) because otherwise their references to the object
     * point into freed memory, allowing crashes.
     */

    if (oPtr->command) {
	if ((((Command *)oPtr->command)->flags && CMD_IS_DELETED)) {
	    /*
	     * Namespace deletion must have been triggered by a trace on command
	     * deletion , meaning that 
	     */
	    deleteAlreadyInProgress = 1;
	}

	Tcl_DeleteCommandFromToken(oPtr->fPtr->interp, oPtr->command);
    }
    if (oPtr->myCommand) {
	Tcl_DeleteCommandFromToken(oPtr->fPtr->interp, oPtr->myCommand);
    }

    /*

	ClearMixins(clsPtr);

	ClearSuperclasses(clsPtr);

	if (clsPtr->subclasses.list) {
	    ckfree(clsPtr->subclasses.list);
	    clsPtr->subclasses.list = NULL;
	    clsPtr->subclasses.num = 0;
	}
	if (clsPtr->instances.list) {
	    ckfree(clsPtr->instances.list);
	    clsPtr->instances.list = NULL;
	    clsPtr->instances.num = 0;
	}
	if (clsPtr->mixinSubs.list) {
	    ckfree(clsPtr->mixinSubs.list);
	    clsPtr->mixinSubs.list = NULL;
	    clsPtr->mixinSubs.num = 0;
	}

	FOREACH_HASH_VALUE(mPtr, &clsPtr->classMethods) {
	    TclOODelMethodRef(mPtr);
	}
	Tcl_DeleteHashTable(&clsPtr->classMethods);

	DelRef(clsPtr);
    }

    /*
     * Delete the object structure itself.
     */

    if (deleteAlreadyInProgress) {
	oPtr->classPtr = NULL;
	oPtr->namespacePtr = NULL;
    } else {
	DelRef(oPtr);
    }

}

/*
 * ----------------------------------------------------------------------
 *
 * TclOORemoveFromInstances --
 *

}

/*
 * ----------------------------------------------------------------------
 *
 * PublicObjectCmd, PrivateObjectCmd, TclOOInvokeObject --
 *
 *	Main entry point for object invocations. The Public* and Private*
 *	wrapper functions (implementations of both object instance commands
 *	and [my]) are just thin wrappers round the main TclOOObjectCmdCore
 *	function. Note that the core is function is NRE-aware.
 *
 * ----------------------------------------------------------------------
 */

}

/*
 * ----------------------------------------------------------------------
 *
 * TclOOObjectCmdCore, FinalizeObjectCall --
 *
 *	Main function for object invocations. Does call chain creation,
 *	management and invocation. The function FinalizeObjectCall exists to
 *	clean up after the non-recursive processing of TclOOObjectCmdCore.
 *
 * ----------------------------------------------------------------------
 */

int
TclOOObjectCmdCore(
    Object *oPtr,		/* The object being invoked. */
    Tcl_Interp *interp,		/* The interpreter containing the object. */
    int objc,			/* How many arguments are being passed in. */
    Tcl_Obj *const *objv,	/* The array of arguments. */
    int flags,			/* Whether this is an invocation through the
				 * public or the private command interface. */
    Class *startCls)		/* Where to start in the call chain, or NULL
				 * if we are to start at the front with
				 * filters and the object's methods (which is
				 * the normal case). */
{
    CallContext *contextPtr;

    }

    /*
     * Advance to the next method implementation in the chain in the method
     * call context while we process the body. However, need to adjust the
     * argument-skip control because we're guaranteed to have a single prefix
     * arg (i.e., 'next') and not the variable amount that can happen because
     * method invocations (i.e., '$obj meth' and 'my meth'), constructors
     * (i.e., '$cls new' and '$cls create obj') and destructors (no args at
     * all) come through the same code.
     */

    contextPtr->index++;
    contextPtr->skip = skip;

    }

    /*
     * Advance to the next method implementation in the chain in the method
     * call context while we process the body. However, need to adjust the
     * argument-skip control because we're guaranteed to have a single prefix
     * arg (i.e., 'next') and not the variable amount that can happen because
     * method invocations (i.e., '$obj meth' and 'my meth'), constructors
     * (i.e., '$cls new' and '$cls create obj') and destructors (no args at
     * all) come through the same code.
     */

    TclNRAddCallback(interp, FinalizeNext, contextPtr,
	    INT2PTR(contextPtr->index), INT2PTR(contextPtr->skip), NULL);
    contextPtr->index++;


/*
 * ----------------------------------------------------------------------
 *
 * TclOOInvokeContext --
 *
 *	Invokes a single step along a method call-chain context. Note that the
 *	invocation of a step along the chain can cause further steps along the
 *	chain to be invoked. Note that this function is written to be as light
 *	in stack usage as possible.
 *
 * ----------------------------------------------------------------------
 */

int

    for (i=cbPtr->filterLength ; i<callPtr->numChain ; i++) {
	if (callPtr->chain[i].mPtr == mPtr &&
		callPtr->chain[i].isFilter == (doneFilters != NULL)) {
	    /*
	     * Call chain semantics states that methods come as *late* in the
	     * call chain as possible. This is done by copying down the
	     * following methods. Note that this does not change the number of
	     * method invocations in the call chain; it just rearranges them.
	     */

	    Class *declCls = callPtr->chain[i].filterDeclarer;

	    for (; i+1<callPtr->numChain ; i++) {
		callPtr->chain[i] = callPtr->chain[i+1];
	    }


/*
 * ----------------------------------------------------------------------
 *
 * TclOOGetCallContext --
 *
 *	Responsible for constructing the call context, an ordered list of all
 *	method implementations to be called as part of a method invocation.
 *	This method is central to the whole operation of the OO system.
 *
 * ----------------------------------------------------------------------
 */

CallContext *
TclOOGetCallContext(

    Tcl_IncrRefCount(methodLiteral);
    objectLiteral = Tcl_NewStringObj("object", -1);
    Tcl_IncrRefCount(objectLiteral);

    /*
     * Do the actual construction of the descriptions. They consist of a list
     * of triples that describe the details of how a method is understood. For
     * each triple, the first word is the type of invocation ("method" is
     * normal, "unknown" is special because it adds the method name as an
     * extra argument when handled by some method types, and "filter" is
     * special because it's a filter method). The second word is the name of
     * the method in question (which differs for "unknown" and "filter" types)
     * and the third word is the full name of the class that declares the
     * method (or "object" if it is declared on the instance).
     */

 * Now, the definition of what an object actually is.
 */

typedef struct Object {
    struct Foundation *fPtr;	/* The basis for the object system. Putting
				 * this here allows the avoidance of quite a
				 * lot of hash lookups on the critical path
				 * for object invocation and creation. */
    Tcl_Namespace *namespacePtr;/* This object's namespace. */
    Tcl_Command command;	/* Reference to this object's public
				 * command. */
    Tcl_Command myCommand;	/* Reference to this object's internal
				 * command. */
    struct Class *selfCls;	/* This object's class. */
    Tcl_HashTable *methodsPtr;	/* Object-local Tcl_Obj (method name) to
				 * Method* mapping. */
    LIST_STATIC(struct Class *) mixins;
				/* Classes mixed into this object. */
    LIST_STATIC(Tcl_Obj *) filters;
				/* List of filter names. */
    struct Class *classPtr;	/* This is non-NULL for all classes, and NULL
				 *  for everything else. It points to the class
				 *  structure. */
    int refCount;		/* Number of strong references to this object.
				 * Note that there may be many more weak
				 * references; this mechanism exists to
				 * avoid Tcl_Preserve. */
    int flags;
    int creationEpoch;		/* Unique value to make comparisons of objects
				 * easier. */
    int epoch;			/* Per-object epoch, incremented when the way
				 * an object should resolve call chains is
				 * changed. */

				 * destructor. */
    Tcl_Obj *clonedName;	/* Shared object containing the name of a
				 * "<cloned>" pseudo-constructor. */
    Tcl_Obj *defineName;	/* Fully qualified name of oo::define. */
} Foundation;

/*
 * A call context structure is built when a method is called. It contains the
 * chain of method implementations that are to be invoked by a particular
 * call, and the process of calling walks the chain, with the [next] command
 * proceeding to the next entry in the chain.
 */

#define CALL_CHAIN_STATIC_SIZE 4

struct MInvoke {
    Method *mPtr;		/* Reference to the method implementation
				 * record. */
    int isFilter;		/* Whether this is a filter invocation. */
    Class *filterDeclarer;	/* What class decided to add the filter; if
				 * NULL, it was added by the object. */
};

typedef struct CallChain {
    int objectCreationEpoch;	/* The object's creation epoch. Note that the
				 * object reference is not stored in the call

    oo::class create bar
    oo::define bar superclass bar1 bar2
    bar create foo
    set result [list [catch {bar create foo} msg] $msg]
    lappend result [bar0 destroy] [oo::object create foo] [foo destroy] \
	[oo::object create bar2] [bar2 destroy]
} {1 {can't create object "foo": command already exists with that name} destroyed {} ::foo {} ::bar2 {}}
test oo-11.5 {OO: cleanup} {
    oo::class create obj1

    trace add command obj1 delete {apply {{name1 name2 action} {
	set namespace [info object namespace $name1]
	namespace delete $namespace
    }}}

    rename obj1 {}
    # No segmentation fault
    return done
} done

test oo-12.1 {OO: filters} {
    oo::class create Aclass
    Aclass create Aobject
    oo::define Aclass {
	method concatenate args {
	    global result