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libkern/c++/OSSymbol.cpp xnu-1699.26.8 xnu-201
--- xnu/xnu-1699.26.8/libkern/c++/OSSymbol.cpp
+++ xnu/xnu-201/libkern/c++/OSSymbol.cpp
@@ -1,33 +1,26 @@
 /*
- * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
+ * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_HEADER_START@
  * 
- * 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.
+ * 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.
  * 
- * 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
+ * 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, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
  * 
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ * @APPLE_LICENSE_HEADER_END@
  */
 /* IOSymbol.cpp created by gvdl on Fri 1998-11-17 */
 
-#include <string.h>
 #include <sys/cdefs.h>
 
 __BEGIN_DECLS
@@ -36,7 +29,6 @@
 
 #include <libkern/c++/OSSymbol.h>
 #include <libkern/c++/OSLib.h>
-#include <string.h>
 
 #define super OSString
 
@@ -51,24 +43,6 @@
 #define ACCUMSIZE(s)
 #endif
 
-#define INITIAL_POOL_SIZE  (exp2ml(1 + log2(kInitBucketCount)))
-
-#define GROW_FACTOR   (1)
-#define SHRINK_FACTOR (3)
-
-#define GROW_POOL()     do \
-    if (count * GROW_FACTOR > nBuckets) { \
-        reconstructSymbols(true); \
-    } \
-while (0)
-
-#define SHRINK_POOL()     do \
-    if (count * SHRINK_FACTOR < nBuckets && \
-        nBuckets > INITIAL_POOL_SIZE) { \
-        reconstructSymbols(false); \
-    } \
-while (0)
-
 class OSSymbolPool
 {
 private:
@@ -79,7 +53,7 @@
     Bucket *buckets;
     unsigned int nBuckets;
     unsigned int count;
-    lck_mtx_t *poolGate;
+    mutex_t *poolGate;
 
     static inline void hashSymbol(const char *s,
                                   unsigned int *hashP,
@@ -102,8 +76,7 @@
     static unsigned long log2(unsigned int x);
     static unsigned long exp2ml(unsigned int x);
 
-    void reconstructSymbols(void);
-    void reconstructSymbols(bool grow);
+    void reconstructSymbols();
 
 public:
     static void *operator new(size_t size);
@@ -115,12 +88,12 @@
 
     bool init();
 
-    inline void closeGate() { lck_mtx_lock(poolGate); };
-    inline void openGate()  { lck_mtx_unlock(poolGate); };
+    inline void closeGate() { mutex_lock(poolGate); };
+    inline void openGate()  { mutex_unlock(poolGate); };
 
     OSSymbol *findSymbol(const char *cString) const;
     OSSymbol *insertSymbol(OSSymbol *sym);
-    void removeSymbol(OSSymbol *sym);
+    void removeSymbol(const char *cString);
 
     OSSymbolPoolState initHashState();
     OSSymbol *nextHashState(OSSymbolPoolState *stateP);
@@ -138,16 +111,14 @@
 
 void OSSymbolPool::operator delete(void *mem, size_t size)
 {
-    kfree(mem, size);
+    kfree((vm_offset_t)mem, size);
     ACCUMSIZE(-size);
 }
 
-extern lck_grp_t *IOLockGroup;
-
 bool OSSymbolPool::init()
 {
     count = 0;
-    nBuckets = INITIAL_POOL_SIZE;
+    nBuckets = exp2ml(1 + log2(kInitBucketCount));
     buckets = (Bucket *) kalloc(nBuckets * sizeof(Bucket));
     ACCUMSIZE(nBuckets * sizeof(Bucket));
     if (!buckets)
@@ -155,7 +126,7 @@
 
     bzero(buckets, nBuckets * sizeof(Bucket));
 
-    poolGate = lck_mtx_alloc_init(IOLockGroup, LCK_ATTR_NULL);
+    poolGate = mutex_alloc(0);
 
     return poolGate != 0;
 }
@@ -172,12 +143,12 @@
 OSSymbolPool::~OSSymbolPool()
 {
     if (buckets) {
-        kfree(buckets, nBuckets * sizeof(Bucket));
+        kfree((vm_offset_t)buckets, nBuckets * sizeof(Bucket));
         ACCUMSIZE(-(nBuckets * sizeof(Bucket)));
     }
 
     if (poolGate)
-        lck_mtx_free(poolGate, IOLockGroup);
+        kfree((vm_offset_t) poolGate, 36 * 4);
 }
 
 unsigned long OSSymbolPool::log2(unsigned int x)
@@ -219,35 +190,14 @@
         return thisBucket->symbolP[stateP->j];
 }
 
-void OSSymbolPool::reconstructSymbols(void)
-{
-    this->reconstructSymbols(true);
-}
-
-void OSSymbolPool::reconstructSymbols(bool grow)
-{
-    unsigned int new_nBuckets = nBuckets;
+void OSSymbolPool::reconstructSymbols()
+{
+    OSSymbolPool old(this);
     OSSymbol *insert;
     OSSymbolPoolState state;
 
-    if (grow) {
-        new_nBuckets += new_nBuckets + 1;
-    } else {
-       /* Don't shrink the pool below the default initial size.
-        */
-        if (nBuckets <= INITIAL_POOL_SIZE) {
-            return;
-        }
-        new_nBuckets = (new_nBuckets - 1) / 2;
-    }
-
-   /* Create old pool to iterate after doing above check, cause it
-    * gets finalized at return.
-    */
-    OSSymbolPool old(this);
-
+    nBuckets += nBuckets + 1;
     count = 0;
-    nBuckets = new_nBuckets;
     buckets = (Bucket *) kalloc(nBuckets * sizeof(Bucket));
     ACCUMSIZE(nBuckets * sizeof(Bucket));
     /* @@@ gvdl: Zero test and panic if can't set up pool */
@@ -275,15 +225,18 @@
         probeSymbol = (OSSymbol *) thisBucket->symbolP;
 
         if (inLen == probeSymbol->length
-        &&  (strncmp(probeSymbol->string, cString, probeSymbol->length) == 0))
+        &&  (strcmp(probeSymbol->string, cString) == 0)
+        &&  (probeSymbol->getRetainCount() >= 1))	// WRONG need when
             return probeSymbol;
-	return 0;
+        else
+            return 0;
     }
 
     for (list = thisBucket->symbolP; j--; list++) {
         probeSymbol = *list;
         if (inLen == probeSymbol->length
-        &&  (strncmp(probeSymbol->string, cString, probeSymbol->length) == 0))
+        &&  (strcmp(probeSymbol->string, cString) == 0)
+        &&  (probeSymbol->getRetainCount() >= 1))	// WRONG need when
             return probeSymbol;
     }
 
@@ -305,14 +258,14 @@
         thisBucket->symbolP = (OSSymbol **) sym;
         thisBucket->count++;
         count++;
-        return sym;
+        return 0;
     }
 
     if (j == 1) {
         probeSymbol = (OSSymbol *) thisBucket->symbolP;
 
         if (inLen == probeSymbol->length
-        &&  strncmp(probeSymbol->string, cString, probeSymbol->length) == 0)
+        &&  strcmp(probeSymbol->string, cString) == 0)
             return probeSymbol;
 
         list = (OSSymbol **) kalloc(2 * sizeof(OSSymbol *));
@@ -323,15 +276,16 @@
         thisBucket->symbolP = list;
         thisBucket->count++;
         count++;
-        GROW_POOL();
-
-        return sym;
+        if (count > nBuckets)
+            reconstructSymbols();
+
+        return 0;
     }
 
     for (list = thisBucket->symbolP; j--; list++) {
         probeSymbol = *list;
         if (inLen == probeSymbol->length
-        &&  strncmp(probeSymbol->string, cString, probeSymbol->length) == 0)
+        &&  strcmp(probeSymbol->string, cString) == 0)
             return probeSymbol;
     }
 
@@ -342,76 +296,71 @@
     /* @@@ gvdl: Zero test and panic if can't set up pool */
     list[0] = sym;
     bcopy(thisBucket->symbolP, list + 1, j * sizeof(OSSymbol *));
-    kfree(thisBucket->symbolP, j * sizeof(OSSymbol *));
+    kfree((vm_offset_t)thisBucket->symbolP, j * sizeof(OSSymbol *));
     ACCUMSIZE(-(j * sizeof(OSSymbol *)));
     thisBucket->symbolP = list;
-    GROW_POOL();
-
-    return sym;
-}
-
-void OSSymbolPool::removeSymbol(OSSymbol *sym)
+    if (count > nBuckets)
+        reconstructSymbols();
+
+    return 0;
+}
+
+void OSSymbolPool::removeSymbol(const char *cString)
 {
     Bucket *thisBucket;
     unsigned int j, inLen, hash;
     OSSymbol *probeSymbol, **list;
 
-    hashSymbol(sym->string, &hash, &inLen); inLen++;
+    hashSymbol(cString, &hash, &inLen); inLen++;
     thisBucket = &buckets[hash % nBuckets];
     j = thisBucket->count;
     list = thisBucket->symbolP;
 
-    if (!j) {
-	// couldn't find the symbol; probably means string hash changed
-        panic("removeSymbol");
+    if (!j)
         return;
-    }
 
     if (j == 1) {
         probeSymbol = (OSSymbol *) list;
 
-        if (probeSymbol == sym) {
+        if (inLen == probeSymbol->length
+        &&  strcmp(probeSymbol->string, cString) == 0) {
             thisBucket->symbolP = 0;
             count--;
             thisBucket->count--;
-            SHRINK_POOL();
             return;
         }
-	// couldn't find the symbol; probably means string hash changed
-    	panic("removeSymbol");
         return;
     }
 
     if (j == 2) {
         probeSymbol = list[0];
-        if (probeSymbol == sym) {
+        if (inLen == probeSymbol->length
+        &&  strcmp(probeSymbol->string, cString) == 0) {
             thisBucket->symbolP = (OSSymbol **) list[1];
-            kfree(list, 2 * sizeof(OSSymbol *));
+            kfree((vm_offset_t)list, 2 * sizeof(OSSymbol *));
 	    ACCUMSIZE(-(2 * sizeof(OSSymbol *)));
             count--;
             thisBucket->count--;
-            SHRINK_POOL();
             return;
         }
 
         probeSymbol = list[1];
-        if (probeSymbol == sym) {
+        if (inLen == probeSymbol->length
+        &&  strcmp(probeSymbol->string, cString) == 0) {
             thisBucket->symbolP = (OSSymbol **) list[0];
-            kfree(list, 2 * sizeof(OSSymbol *));
+            kfree((vm_offset_t)list, 2 * sizeof(OSSymbol *));
 	    ACCUMSIZE(-(2 * sizeof(OSSymbol *)));
             count--;
             thisBucket->count--;
-            SHRINK_POOL();
             return;
         }
-	// couldn't find the symbol; probably means string hash changed
-    	panic("removeSymbol");
         return;
     }
 
     for (; j--; list++) {
         probeSymbol = *list;
-        if (probeSymbol == sym) {
+        if (inLen == probeSymbol->length
+        &&  strcmp(probeSymbol->string, cString) == 0) {
 
             list = (OSSymbol **)
                 kalloc((thisBucket->count-1) * sizeof(OSSymbol *));
@@ -423,7 +372,7 @@
                 bcopy(thisBucket->symbolP + thisBucket->count-j,
                       list + thisBucket->count-1-j,
                       j * sizeof(OSSymbol *));
-            kfree(thisBucket->symbolP, thisBucket->count * sizeof(OSSymbol *));
+            kfree((vm_offset_t)thisBucket->symbolP, thisBucket->count * sizeof(OSSymbol *));
 	    ACCUMSIZE(-(thisBucket->count * sizeof(OSSymbol *)));
             thisBucket->symbolP = list;
             count--;
@@ -431,8 +380,6 @@
             return;
         }
     }
-    // couldn't find the symbol; probably means string hash changed
-    panic("removeSymbol");
 }
 
 /*
@@ -485,60 +432,40 @@
 {
     pool->closeGate();
 
-    OSSymbol *oldSymb = pool->findSymbol(cString);
-    if (!oldSymb) {
-        OSSymbol *newSymb = new OSSymbol;
-        if (!newSymb) {
-            pool->openGate();
-            return newSymb;
-        }
-
+    OSSymbol *newSymb = pool->findSymbol(cString);
+    if (newSymb)
+        newSymb->retain();
+    else if ( (newSymb = new OSSymbol) ) {
 	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();
-    }
-    
-    oldSymb->retain();	// Retain the old symbol before releasing the lock.
-
+	    pool->insertSymbol(newSymb);
+	else {
+	    newSymb->free();
+	    newSymb = 0;
+	}
+    }
     pool->openGate();
-    return oldSymb;
+
+    return newSymb;
 }
 
 const OSSymbol *OSSymbol::withCStringNoCopy(const char *cString)
 {
     pool->closeGate();
 
-    OSSymbol *oldSymb = pool->findSymbol(cString);
-    if (!oldSymb) {
-        OSSymbol *newSymb = new OSSymbol;
-        if (!newSymb) {
-            pool->openGate();
-            return newSymb;
-        }
-
+    OSSymbol *newSymb = pool->findSymbol(cString);
+    if (newSymb)
+        newSymb->retain();
+    else if ( (newSymb = new OSSymbol) ) {
 	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();
-    }
-    
-    oldSymb->retain();	// Retain the old symbol before releasing the lock.
-
+	    pool->insertSymbol(newSymb);
+	else {
+	    newSymb->free();
+	    newSymb = 0;
+	}
+    }
     pool->openGate();
-    return oldSymb;
+
+    return newSymb;
 }
 
 void OSSymbol::checkForPageUnload(void *startAddr, void *endAddr)
@@ -561,21 +488,12 @@
     pool->openGate();
 }
 
-void OSSymbol::taggedRelease(const void *tag) const
-{
-    super::taggedRelease(tag);
-}
-
-void OSSymbol::taggedRelease(const void *tag, const int when) const
+void OSSymbol::free()
 {
     pool->closeGate();
-    super::taggedRelease(tag, when);
+    pool->removeSymbol(string);
     pool->openGate();
-}
-
-void OSSymbol::free()
-{
-    pool->removeSymbol(this);
+    
     super::free();
 }