[Tcl Bug 2857044]: Corrections following audit of Tcl_ObjType freeing

practises; the typePtr field is now cleared when an object ceases to be of
the type.
Also remove some anachronistic techniques (pointless casts, mixed assignments
and tests, etc.)

1 files changed, 19 insertions, 10 deletions

diff --git a/generic/tkCursor.c b/generic/tkCursor.c
index f5a4ca4..5ca7b07 100644
--- a/generic/tkCursor.c
+++ b/generic/tkCursor.c
@@ -11,7 +11,7 @@
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tkCursor.c,v 1.22 2009/01/09 07:03:31 nijtmans Exp $
+ * RCS: @(#) $Id: tkCursor.c,v 1.23 2009/11/21 17:24:42 dkf Exp $
  */
 
 #include "tkInt.h"
@@ -42,6 +42,7 @@ static void		CursorInit(TkDisplay *dispPtr);
 static void		DupCursorObjProc(Tcl_Obj *srcObjPtr,
 			    Tcl_Obj *dupObjPtr);
 static void		FreeCursor(TkCursor *cursorPtr);
+static void		FreeCursorObj(Tcl_Obj *objPtr);
 static void		FreeCursorObjProc(Tcl_Obj *objPtr);
 static TkCursor *	TkcGetCursor(Tcl_Interp *interp, Tk_Window tkwin,
 			    const char *name);
@@ -115,7 +116,7 @@ Tk_AllocCursorFromObj(
 	     * longer in use. Clear the reference.
 	     */
 
-	    FreeCursorObjProc(objPtr);
+	    FreeCursorObj(objPtr);
 	    cursorPtr = NULL;
 	} else if (Tk_Display(tkwin) == cursorPtr->display) {
 	    cursorPtr->resourceRefCount++;
@@ -132,7 +133,7 @@ Tk_AllocCursorFromObj(
     if (cursorPtr != NULL) {
 	TkCursor *firstCursorPtr = Tcl_GetHashValue(cursorPtr->hashPtr);
 
-	FreeCursorObjProc(objPtr);
+	FreeCursorObj(objPtr);
 	for (cursorPtr = firstCursorPtr;  cursorPtr != NULL;
 		cursorPtr = cursorPtr->nextPtr) {
 	    if (Tk_Display(tkwin) == cursorPtr->display) {
@@ -240,7 +241,7 @@ TkcGetCursor(
     }
 
     nameHashPtr = Tcl_CreateHashEntry(&dispPtr->cursorNameTable,
-            string, &isNew);
+	    string, &isNew);
     if (!isNew) {
 	existingCursorPtr = Tcl_GetHashValue(nameHashPtr);
 	for (cursorPtr = existingCursorPtr; cursorPtr != NULL;
@@ -274,7 +275,7 @@ TkcGetCursor(
     cursorPtr->hashPtr = nameHashPtr;
     cursorPtr->nextPtr = existingCursorPtr;
     cursorPtr->idHashPtr = Tcl_CreateHashEntry(&dispPtr->cursorIdTable,
-            (char *) cursorPtr->cursor, &isNew);
+	    (char *) cursorPtr->cursor, &isNew);
     if (!isNew) {
 	Tcl_Panic("cursor already registered in Tk_GetCursor");
     }
@@ -340,7 +341,7 @@ Tk_GetCursorFromData(
     dataKey.bg = bg;
     dataKey.display = Tk_Display(tkwin);
     dataHashPtr = Tcl_CreateHashEntry(&dispPtr->cursorDataTable,
-            (char *) &dataKey, &isNew);
+	    (char *) &dataKey, &isNew);
     if (!isNew) {
 	cursorPtr = Tcl_GetHashValue(dataHashPtr);
 	cursorPtr->resourceRefCount++;
@@ -373,7 +374,7 @@ Tk_GetCursorFromData(
     cursorPtr->hashPtr = dataHashPtr;
     cursorPtr->objRefCount = 0;
     cursorPtr->idHashPtr = Tcl_CreateHashEntry(&dispPtr->cursorIdTable,
-            (char *) cursorPtr->cursor, &isNew);
+	    (char *) cursorPtr->cursor, &isNew);
     cursorPtr->nextPtr = NULL;
 
     if (!isNew) {
@@ -550,13 +551,13 @@ Tk_FreeCursorFromObj(
     Tcl_Obj *objPtr)		/* The Tcl_Obj * to be freed. */
 {
     FreeCursor(GetCursorFromObj(tkwin, objPtr));
-    FreeCursorObjProc(objPtr);
+    FreeCursorObj(objPtr);
 }
 
 /*
  *---------------------------------------------------------------------------
  *
- * FreeCursorFromObjProc --
+ * FreeCursorObjProc, FreeCursorObj --
  *
  *	This proc is called to release an object reference to a cursor.
  *	Called when the object's internal rep is released or when the cached
@@ -576,6 +577,14 @@ static void
 FreeCursorObjProc(
     Tcl_Obj *objPtr)		/* The object we are releasing. */
 {
+    FreeCursorObj(objPtr);
+    objPtr->typePtr = NULL;
+}
+
+static void
+FreeCursorObj(
+    Tcl_Obj *objPtr)		/* The object we are releasing. */
+{
     TkCursor *cursorPtr = objPtr->internalRep.twoPtrValue.ptr1;
 
     if (cursorPtr != NULL) {
@@ -714,7 +723,7 @@ GetCursorFromObj(
     for (cursorPtr = Tcl_GetHashValue(hashPtr);
 	    cursorPtr != NULL; cursorPtr = cursorPtr->nextPtr) {
 	if (Tk_Display(tkwin) == cursorPtr->display) {
-	    FreeCursorObjProc(objPtr);
+	    FreeCursorObj(objPtr);
 	    objPtr->internalRep.twoPtrValue.ptr1 = cursorPtr;
 	    cursorPtr->objRefCount++;
 	    return cursorPtr;