Merge changes Ide388898,Ic49f367c,I1158a808,Iacb6ca5d,I2100dd3a,I5c1abe54,Ib0ef9902,I31dbc523,I570314b3

* changes:
  Merge WebKit at r75315: Update WebKit version
  Merge WebKit at r75315: Add FrameLoaderClient PageCache stubs
  Merge WebKit at r75315: Stub out AXObjectCache::remove()
  Merge WebKit at r75315: Fix ImageBuffer
  Merge WebKit at r75315: Fix PluginData::initPlugins()
  Merge WebKit at r75315: Fix conflicts
  Merge WebKit at r75315: Fix Makefiles
  Merge WebKit at r75315: Move Android-specific WebCore files to Source
  Merge WebKit at r75315: Initial merge by git.

1 files changed, 194 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/wtf/text/StringHash.h b/Source/JavaScriptCore/wtf/text/StringHash.h
new file mode 100644
index 0000000..d7aabdb
--- /dev/null
+++ b/Source/JavaScriptCore/wtf/text/StringHash.h
@@ -0,0 +1,194 @@
+/*
+ * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved
+ * Copyright (C) Research In Motion Limited 2009. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef StringHash_h
+#define StringHash_h
+
+#include "AtomicString.h"
+#include "WTFString.h"
+#include <wtf/Forward.h>
+#include <wtf/HashTraits.h>
+#include <wtf/StringHasher.h>
+#include <wtf/unicode/Unicode.h>
+
+namespace WTF {
+
+    // The hash() functions on StringHash and CaseFoldingHash do not support
+    // null strings. get(), contains(), and add() on HashMap<String,..., StringHash>
+    // cause a null-pointer dereference when passed null strings.
+
+    // FIXME: We should really figure out a way to put the computeHash function that's
+    // currently a member function of StringImpl into this file so we can be a little
+    // closer to having all the nearly-identical hash functions in one place.
+
+    struct StringHash {
+        static unsigned hash(StringImpl* key) { return key->hash(); }
+        static bool equal(const StringImpl* a, const StringImpl* b)
+        {
+            if (a == b)
+                return true;
+            if (!a || !b)
+                return false;
+
+            unsigned aLength = a->length();
+            unsigned bLength = b->length();
+            if (aLength != bLength)
+                return false;
+
+            // FIXME: perhaps we should have a more abstract macro that indicates when
+            // going 4 bytes at a time is unsafe
+#if CPU(ARM) || CPU(SH4) || CPU(MIPS)
+            const UChar* aChars = a->characters();
+            const UChar* bChars = b->characters();
+            for (unsigned i = 0; i != aLength; ++i) {
+                if (*aChars++ != *bChars++)
+                    return false;
+            }
+            return true;
+#else
+            /* Do it 4-bytes-at-a-time on architectures where it's safe */
+            const uint32_t* aChars = reinterpret_cast<const uint32_t*>(a->characters());
+            const uint32_t* bChars = reinterpret_cast<const uint32_t*>(b->characters());
+
+            unsigned halfLength = aLength >> 1;
+            for (unsigned i = 0; i != halfLength; ++i)
+                if (*aChars++ != *bChars++)
+                    return false;
+
+            if (aLength & 1 && *reinterpret_cast<const uint16_t*>(aChars) != *reinterpret_cast<const uint16_t*>(bChars))
+                return false;
+
+            return true;
+#endif
+        }
+
+        static unsigned hash(const RefPtr<StringImpl>& key) { return key->hash(); }
+        static bool equal(const RefPtr<StringImpl>& a, const RefPtr<StringImpl>& b)
+        {
+            return equal(a.get(), b.get());
+        }
+
+        static unsigned hash(const String& key) { return key.impl()->hash(); }
+        static bool equal(const String& a, const String& b)
+        {
+            return equal(a.impl(), b.impl());
+        }
+
+        static const bool safeToCompareToEmptyOrDeleted = false;
+    };
+
+    class CaseFoldingHash {
+    public:
+        template<typename T> static inline UChar foldCase(T ch)
+        {
+            return WTF::Unicode::foldCase(ch);
+        }
+
+        static unsigned hash(const UChar* data, unsigned length)
+        {
+            return StringHasher::createHash<UChar, foldCase<UChar> >(data, length);
+        }
+
+        static unsigned hash(StringImpl* str)
+        {
+            return hash(str->characters(), str->length());
+        }
+
+        static unsigned hash(const char* data, unsigned length)
+        {
+            return StringHasher::createHash<char, foldCase<char> >(data, length);
+        }
+
+        static bool equal(const StringImpl* a, const StringImpl* b)
+        {
+            if (a == b)
+                return true;
+            if (!a || !b)
+                return false;
+            unsigned length = a->length();
+            if (length != b->length())
+                return false;
+            return WTF::Unicode::umemcasecmp(a->characters(), b->characters(), length) == 0;
+        }
+
+        static unsigned hash(const RefPtr<StringImpl>& key) 
+        {
+            return hash(key.get());
+        }
+
+        static bool equal(const RefPtr<StringImpl>& a, const RefPtr<StringImpl>& b)
+        {
+            return equal(a.get(), b.get());
+        }
+
+        static unsigned hash(const String& key)
+        {
+            return hash(key.impl());
+        }
+        static unsigned hash(const AtomicString& key)
+        {
+            return hash(key.impl());
+        }
+        static bool equal(const String& a, const String& b)
+        {
+            return equal(a.impl(), b.impl());
+        }
+        static bool equal(const AtomicString& a, const AtomicString& b)
+        {
+            return (a == b) || equal(a.impl(), b.impl());
+        }
+
+        static const bool safeToCompareToEmptyOrDeleted = false;
+    };
+
+    // This hash can be used in cases where the key is a hash of a string, but we don't
+    // want to store the string. It's not really specific to string hashing, but all our
+    // current uses of it are for strings.
+    struct AlreadyHashed : IntHash<unsigned> {
+        static unsigned hash(unsigned key) { return key; }
+
+        // To use a hash value as a key for a hash table, we need to eliminate the
+        // "deleted" value, which is negative one. That could be done by changing
+        // the string hash function to never generate negative one, but this works
+        // and is still relatively efficient.
+        static unsigned avoidDeletedValue(unsigned hash)
+        {
+            ASSERT(hash);
+            unsigned newHash = hash | (!(hash + 1) << 31);
+            ASSERT(newHash);
+            ASSERT(newHash != 0xFFFFFFFF);
+            return newHash;
+        }
+    };
+
+    template<> struct HashTraits<String> : GenericHashTraits<String> {
+        static const bool emptyValueIsZero = true;
+        static void constructDeletedValue(String& slot) { new (&slot) String(HashTableDeletedValue); }
+        static bool isDeletedValue(const String& slot) { return slot.isHashTableDeletedValue(); }
+    };
+
+}
+
+using WTF::StringHash;
+using WTF::CaseFoldingHash;
+using WTF::AlreadyHashed;
+
+#endif