Convert MediaKeyStatusMap to iterable<BufferSource,MediaKeyStatus>

Source/modules/encryptedmedia/MediaKeyStatusMap.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/encryptedmedia/MediaKeyStatusMap.h"
 
 #include "core/dom/DOMArrayBuffer.h"
 #include "core/dom/DOMArrayPiece.h"
 #include "public/platform/WebData.h"
 #include "wtf/text/WTFString.h"
 
+#include <algorithm>
+
 namespace blink {
 
 // Represents the key ID and associated status.
 class MediaKeyStatusMap::MapEntry final : public GarbageCollectedFinalized<MediaKeyStatusMap::MapEntry> {
 public:
     static MapEntry* create(WebData keyId, const String& status)
     {
         return new MapEntry(keyId, status);
     }
 
     virtual ~MapEntry() { }
 
     DOMArrayBuffer* keyId() const
     {
         return m_keyId.get();
     }
 
     const String& status() const
     {
         return m_status;
     }
 
+    static bool compareLessThan(MapEntry* a, MapEntry* b)
+    {
+        // Compare the keyIds of 2 different MapEntries. Assume that |a| and |b|
+        // are not null. KeyIds are compared byte by byte.
+
+        // Handle null cases first (which shouldn't happen).
+        //    |aKeyId|    |bKeyId|     result
+        //      null        null         == (false)
+        //      null      not-null       <  (true)
+        //    not-null      null         >  (false)
+        if (!a->keyId() || !b->keyId())
+            return b->keyId();
+
+        // Compare the bytes.
+        int result = memcmp(a->keyId()->data(), b->keyId()->data(),
+            std::min(a->keyId()->byteLength(), b->keyId()->byteLength()));
+        if (result != 0)
+            return result < 0;
+
+        // KeyIds are equal to the shared length, so the shorter string is <.
+        return a->keyId()->byteLength() <= b->keyId()->byteLength();
+    }
+
     DEFINE_INLINE_VIRTUAL_TRACE()
     {
     }
 
 private:
     MapEntry(WebData keyId, const String& status)
         : m_keyId(DOMArrayBuffer::create(keyId.data(), keyId.size()))
         , m_status(status)
     {
     }
@@ skipping 38 matching lines @@
 };
 
 void MediaKeyStatusMap::clear()
 {
     m_entries.clear();
 }
 
 void MediaKeyStatusMap::addEntry(WebData keyId, const String& status)
 {
     m_entries.append(MapEntry::create(keyId, status));
+
+    // No need to do any sorting for the first entry.
+    if (m_entries.size() == 1)
+        return;
+
+    // Sort the entries.
+    std::sort(m_entries.begin(), m_entries.end(), MapEntry::compareLessThan);
 }
 
 const MediaKeyStatusMap::MapEntry& MediaKeyStatusMap::at(size_t index) const
 {
     BLINK_ASSERT(index < m_entries.size());
     return *m_entries.at(index);
 }
 
 size_t MediaKeyStatusMap::indexOf(const DOMArrayPiece& key) const
 {
     for (size_t index = 0; index < m_entries.size(); ++index) {
         const auto& current = m_entries.at(index)->keyId();
         if (key == *current)
             return index;
     }
 
     // Not found, so return an index outside the valid range.
     return m_entries.size();
 }
 
+bool MediaKeyStatusMap::has(const ArrayBufferOrArrayBufferView& keyId)
+{
+    size_t index = indexOf(keyId);
+    return index < m_entries.size();
+}
+
+String MediaKeyStatusMap::get(const ArrayBufferOrArrayBufferView& keyId)
+{
+    size_t index = indexOf(keyId);
+    if (index >= m_entries.size())
+        return String();
+    return at(index).status();
+}
+
 PairIterable<ArrayBufferOrArrayBufferView, String>::IterationSource* MediaKeyStatusMap::startIteration(ScriptState*, ExceptionState&)
 {
     return new MapIterationSource(this);
 }
 
-bool MediaKeyStatusMap::getMapEntry(ScriptState*, const ArrayBufferOrArrayBufferView& key, String& value, ExceptionState&)
-{
-    size_t index = indexOf(key);
-    if (index < m_entries.size()) {
-        value = at(index).status();
-        return true;
-    }
-    return false;
-}
-
 DEFINE_TRACE(MediaKeyStatusMap)
 {
     visitor->trace(m_entries);
 }
 
 } // namespace blink