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libkern/c++/OSSymbol.cpp xnu-344.26 xnu-792.13.8
--- xnu/xnu-344.26/libkern/c++/OSSymbol.cpp
+++ xnu/xnu-792.13.8/libkern/c++/OSSymbol.cpp
@@ -1,23 +1,31 @@
 /*
  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_OSREFERENCE_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
- * 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.
- * 
- * @APPLE_LICENSE_HEADER_END@
+ * 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.  The rights granted to you under the 
+ * License may not be used to create, or enable the creation or 
+ * redistribution of, unlawful or unlicensed copies of an Apple operating 
+ * system, or to circumvent, violate, or enable the circumvention or 
+ * violation of, any terms of an Apple operating system software license 
+ * agreement.
+ *
+ * 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, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
+ * Please see the License for the specific language governing rights and 
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  */
 /* IOSymbol.cpp created by gvdl on Fri 1998-11-17 */
 
@@ -93,7 +101,7 @@
     inline void closeGate() { mutex_lock(poolGate); };
     inline void openGate()  { mutex_unlock(poolGate); };
 
-    OSSymbol *findSymbol(const char *cString, OSSymbol ***replace) const;
+    OSSymbol *findSymbol(const char *cString) const;
     OSSymbol *insertSymbol(OSSymbol *sym);
     void removeSymbol(OSSymbol *sym);
 
@@ -113,7 +121,7 @@
 
 void OSSymbolPool::operator delete(void *mem, size_t size)
 {
-    kfree((vm_offset_t)mem, size);
+    kfree(mem, size);
     ACCUMSIZE(-size);
 }
 
@@ -145,12 +153,12 @@
 OSSymbolPool::~OSSymbolPool()
 {
     if (buckets) {
-        kfree((vm_offset_t)buckets, nBuckets * sizeof(Bucket));
+        kfree(buckets, nBuckets * sizeof(Bucket));
         ACCUMSIZE(-(nBuckets * sizeof(Bucket)));
     }
 
     if (poolGate)
-        kfree((vm_offset_t) poolGate, 36 * 4);
+        kfree(poolGate, 36 * 4);
 }
 
 unsigned long OSSymbolPool::log2(unsigned int x)
@@ -210,7 +218,7 @@
         insertSymbol(insert);
 }
 
-OSSymbol *OSSymbolPool::findSymbol(const char *cString, OSSymbol ***replace) const
+OSSymbol *OSSymbolPool::findSymbol(const char *cString) const
 {
     Bucket *thisBucket;
     unsigned int j, inLen, hash;
@@ -220,8 +228,6 @@
     thisBucket = &buckets[hash % nBuckets];
     j = thisBucket->count;
 
-    *replace = NULL;
-
     if (!j)
         return 0;
 
@@ -229,28 +235,16 @@
         probeSymbol = (OSSymbol *) thisBucket->symbolP;
 
         if (inLen == probeSymbol->length
-        &&  (strcmp(probeSymbol->string, cString) == 0)) {
-	    probeSymbol->retain();
-	    if (probeSymbol->getRetainCount() != 0xffff)
-		return probeSymbol;
-	    else
-		// replace this one
-		*replace = (OSSymbol **) &thisBucket->symbolP;
-        }
+        &&  (strcmp(probeSymbol->string, cString) == 0))
+            return probeSymbol;
 	return 0;
     }
 
     for (list = thisBucket->symbolP; j--; list++) {
         probeSymbol = *list;
         if (inLen == probeSymbol->length
-        &&  (strcmp(probeSymbol->string, cString) == 0)) {
-	    probeSymbol->retain();
-	    if (probeSymbol->getRetainCount() != 0xffff)
-		return probeSymbol;
-	    else
-		// replace this one
-		*replace = list;
-	}
+        &&  (strcmp(probeSymbol->string, cString) == 0))
+            return probeSymbol;
     }
 
     return 0;
@@ -271,7 +265,7 @@
         thisBucket->symbolP = (OSSymbol **) sym;
         thisBucket->count++;
         count++;
-        return 0;
+        return sym;
     }
 
     if (j == 1) {
@@ -292,7 +286,7 @@
         if (count > nBuckets)
             reconstructSymbols();
 
-        return 0;
+        return sym;
     }
 
     for (list = thisBucket->symbolP; j--; list++) {
@@ -309,13 +303,13 @@
     /* @@@ gvdl: Zero test and panic if can't set up pool */
     list[0] = sym;
     bcopy(thisBucket->symbolP, list + 1, j * sizeof(OSSymbol *));
-    kfree((vm_offset_t)thisBucket->symbolP, j * sizeof(OSSymbol *));
+    kfree(thisBucket->symbolP, j * sizeof(OSSymbol *));
     ACCUMSIZE(-(j * sizeof(OSSymbol *)));
     thisBucket->symbolP = list;
     if (count > nBuckets)
         reconstructSymbols();
 
-    return 0;
+    return sym;
 }
 
 void OSSymbolPool::removeSymbol(OSSymbol *sym)
@@ -348,7 +342,7 @@
         probeSymbol = list[0];
         if (probeSymbol == sym) {
             thisBucket->symbolP = (OSSymbol **) list[1];
-            kfree((vm_offset_t)list, 2 * sizeof(OSSymbol *));
+            kfree(list, 2 * sizeof(OSSymbol *));
 	    ACCUMSIZE(-(2 * sizeof(OSSymbol *)));
             count--;
             thisBucket->count--;
@@ -358,7 +352,7 @@
         probeSymbol = list[1];
         if (probeSymbol == sym) {
             thisBucket->symbolP = (OSSymbol **) list[0];
-            kfree((vm_offset_t)list, 2 * sizeof(OSSymbol *));
+            kfree(list, 2 * sizeof(OSSymbol *));
 	    ACCUMSIZE(-(2 * sizeof(OSSymbol *)));
             count--;
             thisBucket->count--;
@@ -381,7 +375,7 @@
                 bcopy(thisBucket->symbolP + thisBucket->count-j,
                       list + thisBucket->count-1-j,
                       j * sizeof(OSSymbol *));
-            kfree((vm_offset_t)thisBucket->symbolP, thisBucket->count * sizeof(OSSymbol *));
+            kfree(thisBucket->symbolP, thisBucket->count * sizeof(OSSymbol *));
 	    ACCUMSIZE(-(thisBucket->count * sizeof(OSSymbol *)));
             thisBucket->symbolP = list;
             count--;
@@ -439,48 +433,62 @@
 
 const OSSymbol *OSSymbol::withCString(const char *cString)
 {
-    OSSymbol **replace;
-
     pool->closeGate();
 
-    OSSymbol *newSymb = pool->findSymbol(cString, &replace);
-    if (!newSymb && (newSymb = new OSSymbol) ) {
-	if (newSymb->OSString::initWithCString(cString)) {
-	    if (replace)
-		*replace = newSymb;
-	    else
-		pool->insertSymbol(newSymb);
-	} else {
+    OSSymbol *oldSymb = pool->findSymbol(cString);
+    if (!oldSymb) {
+        OSSymbol *newSymb = new OSSymbol;
+        if (!newSymb) {
+            pool->openGate();
+            return newSymb;
+        }
+
+	if (newSymb->OSString::initWithCString(cString))
+	    oldSymb = pool->insertSymbol(newSymb);
+        
+        if (newSymb == oldSymb) {
+            pool->openGate();
+            return newSymb;	// return the newly created & inserted symbol.
+        }
+        else
+            // Somebody else inserted the new symbol so free our copy
 	    newSymb->OSString::free();
-	    newSymb = 0;
-	}
-    }
+    }
+    
+    oldSymb->retain();	// Retain the old symbol before releasing the lock.
+
     pool->openGate();
-
-    return newSymb;
+    return oldSymb;
 }
 
 const OSSymbol *OSSymbol::withCStringNoCopy(const char *cString)
 {
-    OSSymbol **replace;
-
     pool->closeGate();
 
-    OSSymbol *newSymb = pool->findSymbol(cString, &replace);
-    if (!newSymb && (newSymb = new OSSymbol) ) {
-	if (newSymb->OSString::initWithCStringNoCopy(cString)) {
-	    if (replace)
-		*replace = newSymb;
-	    else
-		pool->insertSymbol(newSymb);
-	} else {
+    OSSymbol *oldSymb = pool->findSymbol(cString);
+    if (!oldSymb) {
+        OSSymbol *newSymb = new OSSymbol;
+        if (!newSymb) {
+            pool->openGate();
+            return newSymb;
+        }
+
+	if (newSymb->OSString::initWithCStringNoCopy(cString))
+	    oldSymb = pool->insertSymbol(newSymb);
+        
+        if (newSymb == oldSymb) {
+            pool->openGate();
+            return newSymb;	// return the newly created & inserted symbol.
+        }
+        else
+            // Somebody else inserted the new symbol so free our copy
 	    newSymb->OSString::free();
-	    newSymb = 0;
-	}
-    }
+    }
+    
+    oldSymb->retain();	// Retain the old symbol before releasing the lock.
+
     pool->openGate();
-
-    return newSymb;
+    return oldSymb;
 }
 
 void OSSymbol::checkForPageUnload(void *startAddr, void *endAddr)
@@ -503,12 +511,21 @@
     pool->openGate();
 }
 
+void OSSymbol::taggedRelease(const void *tag) const
+{
+    super::taggedRelease(tag);
+}
+
+void OSSymbol::taggedRelease(const void *tag, const int when) const
+{
+    pool->closeGate();
+    super::taggedRelease(tag, when);
+    pool->openGate();
+}
+
 void OSSymbol::free()
 {
-    pool->closeGate();
     pool->removeSymbol(this);
-    pool->openGate();
-    
     super::free();
 }