Merge WebKit at r75315: Initial merge by git.

Change-Id: I570314b346ce101c935ed22a626b48c2af266b84

1 files changed, 187 insertions, 0 deletions

diff --git a/Source/WebCore/storage/StorageMap.cpp b/Source/WebCore/storage/StorageMap.cpp
new file mode 100644
index 0000000..790fde2
--- /dev/null
+++ b/Source/WebCore/storage/StorageMap.cpp
@@ -0,0 +1,187 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "StorageMap.h"
+
+#if ENABLE(DOM_STORAGE)
+
+namespace WebCore {
+
+PassRefPtr<StorageMap> StorageMap::create(unsigned quota)
+{
+    return adoptRef(new StorageMap(quota));
+}
+
+StorageMap::StorageMap(unsigned quota)
+    : m_iterator(m_map.end())
+    , m_iteratorIndex(UINT_MAX)
+    , m_quotaSize(quota)  // quota measured in bytes
+    , m_currentLength(0)
+{
+}
+
+PassRefPtr<StorageMap> StorageMap::copy()
+{
+    RefPtr<StorageMap> newMap = create(m_quotaSize);
+    newMap->m_map = m_map;
+    newMap->m_currentLength = m_currentLength;
+    return newMap.release();
+}
+
+void StorageMap::invalidateIterator()
+{
+    m_iterator = m_map.end();
+    m_iteratorIndex = UINT_MAX;
+}
+
+void StorageMap::setIteratorToIndex(unsigned index)
+{
+    // FIXME: Once we have bidirectional iterators for HashMap we can be more intelligent about this.
+    // The requested index will be closest to begin(), our current iterator, or end(), and we
+    // can take the shortest route.
+    // Until that mechanism is available, we'll always increment our iterator from begin() or current.
+
+    if (m_iteratorIndex == index)
+        return;
+
+    if (index < m_iteratorIndex) {
+        m_iteratorIndex = 0;
+        m_iterator = m_map.begin();
+        ASSERT(m_iterator != m_map.end());
+    }
+
+    while (m_iteratorIndex < index) {
+        ++m_iteratorIndex;
+        ++m_iterator;
+        ASSERT(m_iterator != m_map.end());
+    }
+}
+
+unsigned StorageMap::length() const
+{
+    return m_map.size();
+}
+
+String StorageMap::key(unsigned index)
+{
+    if (index >= length())
+        return String();
+
+    setIteratorToIndex(index);
+    return m_iterator->first;
+}
+
+String StorageMap::getItem(const String& key) const
+{
+    return m_map.get(key);
+}
+
+PassRefPtr<StorageMap> StorageMap::setItem(const String& key, const String& value, String& oldValue, bool& quotaException)
+{
+    ASSERT(!value.isNull());
+    quotaException = false;
+
+    // Implement copy-on-write semantics here.  We're guaranteed that the only refs of StorageMaps belong to Storage objects
+    // so if more than one Storage object refs this map, copy it before mutating it.
+    if (refCount() > 1) {
+        RefPtr<StorageMap> newStorageMap = copy();
+        newStorageMap->setItem(key, value, oldValue, quotaException);
+        return newStorageMap.release();
+    }
+
+    // Quota tracking.  This is done in a couple of steps to keep the overflow tracking simple.
+    unsigned newLength = m_currentLength;
+    bool overflow = newLength + value.length() < newLength;
+    newLength += value.length();
+
+    oldValue = m_map.get(key);
+    overflow |= newLength - oldValue.length() > newLength;
+    newLength -= oldValue.length();
+
+    unsigned adjustedKeyLength = oldValue.isNull() ? key.length() : 0;
+    overflow |= newLength + adjustedKeyLength < newLength;
+    newLength += adjustedKeyLength;
+
+    ASSERT(!overflow);  // Overflow is bad...even if quotas are off.
+    bool overQuota = newLength > m_quotaSize / sizeof(UChar);
+    if (m_quotaSize != noQuota && (overflow || overQuota)) {
+        quotaException = true;
+        return 0;
+    }
+    m_currentLength = newLength;
+
+    pair<HashMap<String, String>::iterator, bool> addResult = m_map.add(key, value);
+    if (!addResult.second)
+        addResult.first->second = value;
+
+    invalidateIterator();
+
+    return 0;
+}
+
+PassRefPtr<StorageMap> StorageMap::removeItem(const String& key, String& oldValue)
+{
+    // Implement copy-on-write semantics here.  We're guaranteed that the only refs of StorageMaps belong to Storage objects
+    // so if more than one Storage object refs this map, copy it before mutating it.
+    if (refCount() > 1) {
+        RefPtr<StorageMap> newStorage = copy();
+        newStorage->removeItem(key, oldValue);
+        return newStorage.release();
+    }
+
+    oldValue = m_map.take(key);
+    if (!oldValue.isNull()) {
+        invalidateIterator();
+        ASSERT(m_currentLength - key.length() <= m_currentLength);
+        m_currentLength -= key.length();
+    }
+    ASSERT(m_currentLength - oldValue.length() <= m_currentLength);
+    m_currentLength -= oldValue.length();
+
+    return 0;
+}
+
+bool StorageMap::contains(const String& key) const
+{
+    return m_map.contains(key);
+}
+
+void StorageMap::importItem(const String& key, const String& value)
+{
+    // Be sure to copy the keys/values as items imported on a background thread are destined
+    // to cross a thread boundary
+    pair<HashMap<String, String>::iterator, bool> result = m_map.add(key.threadsafeCopy(), value.threadsafeCopy());
+    ASSERT(result.second);  // True if the key didn't exist previously.
+
+    ASSERT(m_currentLength + key.length() >= m_currentLength);
+    m_currentLength += key.length();
+    ASSERT(m_currentLength + value.length() >= m_currentLength);
+    m_currentLength += value.length();
+}
+
+}
+
+#endif // ENABLE(DOM_STORAGE)