A bit set class. Will be used for font subsetting.

Committed on behalf of arthurhsu@chromium.org with a few final nits.

Original CL: http://codereview.appspot.com/4627077

Review URL: http://codereview.appspot.com/4657070

git-svn-id: http://skia.googlecode.com/svn/trunk@1788 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 65 insertions, 0 deletions

diff --git a/include/pdf/SkBitSet.h b/include/pdf/SkBitSet.h
new file mode 100755
index 0000000000..84d52e547c
--- /dev/null
+++ b/include/pdf/SkBitSet.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2011 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef SkBitSet_DEFINED
+#define SkBitSet_DEFINED
+
+#include "SkTypes.h"
+
+class SkBitSet {
+public:
+    /** NumberOfBits must be greater than zero.
+     */
+    explicit SkBitSet(int numberOfBits);
+    explicit SkBitSet(const SkBitSet& source);
+
+    const SkBitSet& operator=(const SkBitSet& rhs);
+    bool operator==(const SkBitSet& rhs);
+    bool operator!=(const SkBitSet& rhs);
+
+    /** Clear all data.
+     */
+    void clearAll();
+
+    /** Set the value of the index-th bit.
+     */
+    void setBit(int index, bool value);
+
+    /** Test if bit index is set.
+     */
+    bool isBitSet(int index);
+
+    /** Or bits from source.  false is returned if this doesn't have the same
+     *  bit count as source.
+     */
+    bool orBits(SkBitSet& source);
+
+private:
+    SkAutoFree fBitData;
+    // Dword (32-bit) count of the bitset.
+    size_t fDwordCount;
+    size_t fBitCount;
+
+    uint32_t* internalGet(int index) {
+        SkASSERT((size_t)index < fBitCount);
+        size_t internalIndex = index / 32;
+        SkASSERT(internalIndex < fDwordCount);
+        return (uint32_t*)fBitData.get() + internalIndex;
+    }
+};
+
+
+#endif