Add some consistecy checks

Headers/GNUstepBase/NSObject+GNUstepBase.h

@@ -241,21 +241,31 @@ extern "C" {
  */
 + (BOOL) isExiting;
 
-/** This method informs the system that anAddress is a pointer whose content
- * has been leaked and should be released and zeroed out (if clean-up is
- * enabled) at process exit.  If the content of the location is changed
- * between the point where this method is called and the process exits,
- * then the new content of the address is what will be released on clean-up.
+/** This method informs the system that anObject should be retained to
+ * persist until the process exits.  If clean-up is enabled the object
+ * should be released upon process exit.
+ * If this method is called while the process is already existing it
+ * returns nil, otherwise it returnes the retained argument.
+ * Raises an exception if anObject has already been leaked or if it is
+ * nil (unless the process is exiting).
+ */
++ (id) NS_RETURNS_RETAINED leak: (id)anObject;
+
+/** This method informs the system that the object at anAddress has been
+ * retained to persist until the process exits.  If clean-up is enabled
+ * the object should be released (and the address content zeroed out)
+ * upon process exit.
+ * If this method is called while the process is already existing it releases
+ * the object and zeros out the memory location then returns nil, otherwise
+ * it returns the object found at the memory location.
+ * Raises an exception if anAddress (or the object at anAddress) has already
+ * been leaked or if it is nil (unless the process is exiting).
  */
 + (void) leaked: (id*)anAddress;
 
-/** Deprecated: use +leaked: instead.
+/** DEPRECATED ... use +leaked: instead.
  */
-+ (id) NS_RETURNS_RETAINED leak: (id)anObject GS_DEPRECATED_FUNC;
-
-/** Deprecated: use +leaked: instead.
- */
-+ (id) NS_RETURNS_RETAINED leakAt: (id*)anAddress ;//GS_DEPRECATED_FUNC;
++ (id) NS_RETURNS_RETAINED leakAt: (id*)anAddress;
 
 /** Sets the receiver to have its +atExit method called at the point when
  * the process terminates.<br />

Source/Additions/NSObject+GNUstepBase.m

@@ -227,26 +227,9 @@ handleExit()
   return isExiting;
 }
 
-+ (void) leaked: (id*)anAddress
-{
-  struct exitLink	*l;
-
-  NSAssert(*anAddress && [*anAddress isKindOfClass: [NSObject class]],
-    NSInvalidArgumentException);
-  l = (struct exitLink*)malloc(sizeof(struct exitLink));
-  l->at = anAddress;
-  l->obj = *anAddress;
-  l->sel = 0;
-  setup();
-  [exitLock lock];
-  l->next = exited;
-  exited = l;
-  [exitLock unlock];
-}
-
 + (id) leakAt: (id*)anAddress
 {
-  struct exitLink	*l;
+  struct exitLink       *l;
 
   l = (struct exitLink*)malloc(sizeof(struct exitLink));
   l->at = anAddress;
@@ -260,16 +243,69 @@ handleExit()
   return l->obj;
 }
 
++ (void) leaked: (id*)anAddress
+{
+  struct exitLink	*l;
+
+  NSAssert(anAddress != NULL, NSInvalidArgumentException);
+  if (isExiting)
+    {
+      [*anAddress release];
+      *anAddress = nil;
+      return nil;
+    }
+  NSAssert([*anAddress isKindOfClass: [NSObject class]],
+    NSInvalidArgumentException);
+  setup();
+  [exitLock lock];
+  for (l = exited; l != NULL; l = l->next)
+    {
+      if (l->at == anAddress)
+	{
+	  [exitLock unlock];
+	  [NSException raise: NSInvalidArgumentException
+		      format: @"Repeated use of leak address %p", anAddress];
+	}
+      if (*anAddress != nil && *anAddress == l->obj)
+	{
+	  [exitLock unlock];
+	  [NSException raise: NSInvalidArgumentException
+		      format: @"Repeated use of leak object %p", *anAddress];
+	}
+    }
+  l = (struct exitLink*)malloc(sizeof(struct exitLink));
+  l->at = anAddress;
+  l->obj = *anAddress;
+  l->sel = 0;
+  l->next = exited;
+  exited = l;
+  [exitLock unlock];
+  return l->obj;
+}
+
 + (id) leak: (id)anObject
 {
   struct exitLink	*l;
 
+  if (nil == anObject || isExiting)
+    {
+      return nil;
+    }
+  setup();
+  [exitLock lock];
+  for (l = exited; l != NULL; l = l->next)
+    {
+      if (l->obj == anObject || (l->at != nil && *l->at == anObject))
+	{
+	  [exitLock unlock];
+	  [NSException raise: NSInvalidArgumentException
+		      format: @"Repeated use of leak object %p", anObject];
+	}
+    }
   l = (struct exitLink*)malloc(sizeof(struct exitLink));
   l->at = 0;
   l->obj = [anObject retain];
   l->sel = 0;
-  setup();
-  [exitLock lock];
   l->next = exited;
   exited = l;
   [exitLock unlock];