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libkern/c++/OSSymbol.cpp xnu-201.14 xnu-792.22.5
--- xnu/xnu-201.14/libkern/c++/OSSymbol.cpp
+++ xnu/xnu-792.22.5/libkern/c++/OSSymbol.cpp
@@ -1,26 +1,33 @@
 /*
  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_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 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.
  * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * 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@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /* IOSymbol.cpp created by gvdl on Fri 1998-11-17 */
 
+#include <string.h>
 #include <sys/cdefs.h>
 
 __BEGIN_DECLS
@@ -29,6 +36,7 @@
 
 #include <libkern/c++/OSSymbol.h>
 #include <libkern/c++/OSLib.h>
+#include <string.h>
 
 #define super OSString
 
@@ -93,7 +101,7 @@
 
     OSSymbol *findSymbol(const char *cString) const;
     OSSymbol *insertSymbol(OSSymbol *sym);
-    void removeSymbol(const char *cString);
+    void removeSymbol(OSSymbol *sym);
 
     OSSymbolPoolState initHashState();
     OSSymbol *nextHashState(OSSymbolPoolState *stateP);
@@ -111,7 +119,7 @@
 
 void OSSymbolPool::operator delete(void *mem, size_t size)
 {
-    kfree((vm_offset_t)mem, size);
+    kfree(mem, size);
     ACCUMSIZE(-size);
 }
 
@@ -143,12 +151,12 @@
 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)
@@ -225,18 +233,15 @@
         probeSymbol = (OSSymbol *) thisBucket->symbolP;
 
         if (inLen == probeSymbol->length
-        &&  (strcmp(probeSymbol->string, cString) == 0)
-        &&  (probeSymbol->getRetainCount() >= 1))	// WRONG need when
+        &&  (strcmp(probeSymbol->string, cString) == 0))
             return probeSymbol;
-        else
-            return 0;
+	return 0;
     }
 
     for (list = thisBucket->symbolP; j--; list++) {
         probeSymbol = *list;
         if (inLen == probeSymbol->length
-        &&  (strcmp(probeSymbol->string, cString) == 0)
-        &&  (probeSymbol->getRetainCount() >= 1))	// WRONG need when
+        &&  (strcmp(probeSymbol->string, cString) == 0))
             return probeSymbol;
     }
 
@@ -258,7 +263,7 @@
         thisBucket->symbolP = (OSSymbol **) sym;
         thisBucket->count++;
         count++;
-        return 0;
+        return sym;
     }
 
     if (j == 1) {
@@ -279,7 +284,7 @@
         if (count > nBuckets)
             reconstructSymbols();
 
-        return 0;
+        return sym;
     }
 
     for (list = thisBucket->symbolP; j--; list++) {
@@ -296,22 +301,22 @@
     /* @@@ 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;
-}
-
-void OSSymbolPool::removeSymbol(const char *cString)
+    return sym;
+}
+
+void OSSymbolPool::removeSymbol(OSSymbol *sym)
 {
     Bucket *thisBucket;
     unsigned int j, inLen, hash;
     OSSymbol *probeSymbol, **list;
 
-    hashSymbol(cString, &hash, &inLen); inLen++;
+    hashSymbol(sym->string, &hash, &inLen); inLen++;
     thisBucket = &buckets[hash % nBuckets];
     j = thisBucket->count;
     list = thisBucket->symbolP;
@@ -322,8 +327,7 @@
     if (j == 1) {
         probeSymbol = (OSSymbol *) list;
 
-        if (inLen == probeSymbol->length
-        &&  strcmp(probeSymbol->string, cString) == 0) {
+        if (probeSymbol == sym) {
             thisBucket->symbolP = 0;
             count--;
             thisBucket->count--;
@@ -334,10 +338,9 @@
 
     if (j == 2) {
         probeSymbol = list[0];
-        if (inLen == probeSymbol->length
-        &&  strcmp(probeSymbol->string, cString) == 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--;
@@ -345,10 +348,9 @@
         }
 
         probeSymbol = list[1];
-        if (inLen == probeSymbol->length
-        &&  strcmp(probeSymbol->string, cString) == 0) {
+        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--;
@@ -359,8 +361,7 @@
 
     for (; j--; list++) {
         probeSymbol = *list;
-        if (inLen == probeSymbol->length
-        &&  strcmp(probeSymbol->string, cString) == 0) {
+        if (probeSymbol == sym) {
 
             list = (OSSymbol **)
                 kalloc((thisBucket->count-1) * sizeof(OSSymbol *));
@@ -372,7 +373,7 @@
                 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--;
@@ -432,40 +433,60 @@
 {
     pool->closeGate();
 
-    OSSymbol *newSymb = pool->findSymbol(cString);
-    if (newSymb)
-        newSymb->retain();
-    else if ( (newSymb = new OSSymbol) ) {
+    OSSymbol *oldSymb = pool->findSymbol(cString);
+    if (!oldSymb) {
+        OSSymbol *newSymb = new OSSymbol;
+        if (!newSymb) {
+            pool->openGate();
+            return newSymb;
+        }
+
 	if (newSymb->OSString::initWithCString(cString))
-	    pool->insertSymbol(newSymb);
-	else {
-	    newSymb->free();
-	    newSymb = 0;
-	}
-    }
+	    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();
+    }
+    
+    oldSymb->retain();	// Retain the old symbol before releasing the lock.
+
     pool->openGate();
-
-    return newSymb;
+    return oldSymb;
 }
 
 const OSSymbol *OSSymbol::withCStringNoCopy(const char *cString)
 {
     pool->closeGate();
 
-    OSSymbol *newSymb = pool->findSymbol(cString);
-    if (newSymb)
-        newSymb->retain();
-    else if ( (newSymb = new OSSymbol) ) {
+    OSSymbol *oldSymb = pool->findSymbol(cString);
+    if (!oldSymb) {
+        OSSymbol *newSymb = new OSSymbol;
+        if (!newSymb) {
+            pool->openGate();
+            return newSymb;
+        }
+
 	if (newSymb->OSString::initWithCStringNoCopy(cString))
-	    pool->insertSymbol(newSymb);
-	else {
-	    newSymb->free();
-	    newSymb = 0;
-	}
-    }
+	    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();
+    }
+    
+    oldSymb->retain();	// Retain the old symbol before releasing the lock.
+
     pool->openGate();
-
-    return newSymb;
+    return oldSymb;
 }
 
 void OSSymbol::checkForPageUnload(void *startAddr, void *endAddr)
@@ -488,12 +509,21 @@
     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(string);
-    pool->openGate();
-    
+    pool->removeSymbol(this);
     super::free();
 }