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--- xnu/xnu-344/libkern/c++/OSObject.cpp
+++ xnu/xnu-517/libkern/c++/OSObject.cpp
@@ -3,19 +3,22 @@
*
* @APPLE_LICENSE_HEADER_START@
*
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/
@@ -101,6 +104,12 @@
bool OSObject::init()
{ return true; }
+#if (!__ppc__) || (__GNUC__ < 3)
+
+// Implemented in assembler in post gcc 3.x systems as we have a problem
+// where the destructor in gcc2.95 gets 2 arguments. The second argument
+// appears to be a flag argument. I have copied the assembler from Puma xnu
+// to OSRuntimeSupport.c So for 2.95 builds use the C
void OSObject::free()
{
const OSMetaClass *meta = getMetaClass();
@@ -109,6 +118,7 @@
meta->instanceDestructed();
delete this;
}
+#endif /* (!__ppc__) || (__GNUC__ < 3) */
int OSObject::getRetainCount() const
{
@@ -117,42 +127,44 @@
void OSObject::taggedRetain(const void *tag) const
{
-#if !DEBUG
volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
UInt32 inc = 1;
UInt32 origCount;
UInt32 newCount;
- // Increment the collecion bucket.
+ // Increment the collection bucket.
if ((const void *) OSTypeID(OSCollection) == tag)
inc |= (1UL<<16);
do {
origCount = *countP;
- if (-1UL == origCount)
- // @@@ Pinot: panic("Attempting to retain a freed object");
- return;
+ if ( ((UInt16) origCount | 0x1) == 0xffff ) {
+ const char *msg;
+ if (origCount & 0x1) {
+ // If count == 0xffff that means we are freeing now so we can
+ // just return obviously somebody is cleaning up dangling
+ // references.
+ msg = "Attempting to retain a freed object";
+ }
+ else {
+ // If count == 0xfffe then we have wrapped our reference count.
+ // We should stop counting now as this reference must be
+ // leaked rather than accidently wrapping around the clock and
+ // freeing a very active object later.
+
+#if !DEBUG
+ break; // Break out of update loop which pegs the reference
+#else DEBUG
+ // @@@ gvdl: eventually need to make this panic optional
+ // based on a boot argument i.e. debug= boot flag
+ msg = "About to wrap the reference count, reference leak?";
+#endif /* !DEBUG */
+ }
+ panic("OSObject::refcount: %s", msg);
+ }
newCount = origCount + inc;
} while (!OSCompareAndSwap(origCount, newCount, (UInt32 *) countP));
-#else
- volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
- UInt32 inc = 1;
- UInt32 origCount;
- UInt32 newCount;
-
- // Increment the collecion bucket.
- if ((const void *) OSTypeID(OSCollection) == tag)
- inc |= (1UL<<16);
-
- do {
- origCount = *countP;
- if (-1UL == origCount)
- return; // We are freeing so leave now.
-
- newCount = origCount + inc;
- } while (!OSCompareAndSwap(origCount, newCount, (UInt32 *) countP));
-#endif
}
void OSObject::taggedRelease(const void *tag) const
@@ -162,25 +174,44 @@
void OSObject::taggedRelease(const void *tag, const int when) const
{
-#if !DEBUG
volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
UInt32 dec = 1;
UInt32 origCount;
UInt32 newCount;
UInt32 actualCount;
- // Increment the collecion bucket.
+ // Increment the collection bucket.
if ((const void *) OSTypeID(OSCollection) == tag)
dec |= (1UL<<16);
do {
origCount = *countP;
- if (-1UL == origCount)
- return; // We are freeing already leave now.
-
+
+ if ( ((UInt16) origCount | 0x1) == 0xffff ) {
+ if (origCount & 0x1) {
+ // If count == 0xffff that means we are freeing now so we can
+ // just return obviously somebody is cleaning up some dangling
+ // references. So we blow out immediately.
+ return;
+ }
+ else {
+ // If count == 0xfffe then we have wrapped our reference
+ // count. We should stop counting now as this reference must be
+ // leaked rather than accidently freeing an active object later.
+
+#if !DEBUG
+ return; // return out of function which pegs the reference
+#else DEBUG
+ // @@@ gvdl: eventually need to make this panic optional
+ // based on a boot argument i.e. debug= boot flag
+ panic("OSObject::refcount: %s",
+ "About to unreference a pegged object, reference leak?");
+#endif /* !DEBUG */
+ }
+ }
actualCount = origCount - dec;
- if ((SInt16) actualCount < when)
- newCount = (UInt32) -1;
+ if ((UInt16) actualCount < when)
+ newCount = 0xffff;
else
newCount = actualCount;
@@ -199,49 +230,8 @@
getClassName(this));
// Check for a 'free' condition and that if we are first through
- if ((UInt32) -1 == newCount)
+ if (newCount == 0xffff)
((OSObject *) this)->free();
-#else
- // @@@ Pinot: Need to update the debug build release code.
- volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
- UInt32 dec = 1;
- UInt32 origCount;
- UInt32 newCount;
-
- // Increment the collecion bucket.
- if ((const void *) OSTypeID(OSCollection) == tag)
- dec |= (1UL<<16);
-
- do {
- origCount = *countP;
- if (-1UL == origCount)
- return; // We are freeing already leave now.
-
- newCount = origCount - dec;
- } while (!OSCompareAndSwap(origCount, newCount, (UInt32 *) countP));
-
- //
- // This panic means that we have just attempted to release an object
- // who's retain count has gone to less than the number of collections
- // it is a member off. Take a panic immediately.
- // In Fact the panic MAY not be a registry corruption but it is
- // ALWAYS the wrong thing to do. I call it a registry corruption 'cause
- // the registry is the biggest single use of a network of collections.
- //
- if ((UInt16) newCount < (newCount >> 16))
- panic("A driver releasing a(n) %s has corrupted the registry\n",
- getClassName(this));
-
- // Check for a release too many
- if ((SInt16) newCount < 0)
- panic("An object has had a release too many\n",
- getClassName(this));
-
- // Check for a 'free' condition and that if we are first through
- if ((SInt16) newCount < when
- && OSCompareAndSwap(newCount, -1UL, (UInt32 *) countP))
- ((OSObject *) this)->free();
-#endif
}
void OSObject::release() const