Index: components/rappor/bloom_filter.h |
diff --git a/components/rappor/bloom_filter.h b/components/rappor/bloom_filter.h |
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+// Copyright 2014 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. |
+ |
+#ifndef COMPONENTS_RAPPOR_BLOOM_FILTER_H_ |
+#define COMPONENTS_RAPPOR_BLOOM_FILTER_H_ |
+ |
+#include <stdint.h> |
+ |
+#include <string> |
+#include <vector> |
+ |
+#include "base/basictypes.h" |
+#include "components/rappor/byte_vector_utils.h" |
+ |
+namespace rappor { |
+ |
+// BloomFilter is a simple Bloom filter for keeping track of a set of strings. |
+class BloomFilter { |
+ public: |
+ // Constructs a BloomFilter using |bytes_size| bytes of Bloom filter bits, |
+ // and |hash_function_count| hash functions to set bits in the filter. The |
+ // hash functions will be generated by using seeds in the range |
+ // |hash_seed_offset| to (|hash_seed_offset| + |hash_function_count|). |
+ BloomFilter(uint32_t bytes_size, |
+ uint32_t hash_function_count, |
+ uint32_t hash_seed_offset); |
+ ~BloomFilter(); |
+ |
+ // Add a single string to the Bloom filter. |
+ void AddString(const std::string& str); |
+ |
+ // Returns the current value of the Bloom filter's bit array. |
+ const ByteVector& bytes() const { return bytes_; }; |
+ |
+ // Returns the number of bits set for each string added to the filter. |
+ uint32_t hash_function_count() const { return hash_function_count_; }; |
+ |
+ private: |
+ // Stores the byte array of the Bloom filter. |
+ ByteVector bytes_; |
+ // The number of bits to set for each string added. |
+ uint32_t hash_function_count_; |
+ uint32_t hash_seed_offset_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(BloomFilter); |
+}; |
+ |
+} // namespace rappor |
+ |
+#endif // COMPONENTS_RAPPOR_BLOOM_FILTER_H_ |