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 // Copyright 2010 Google 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:

 //

 //     * Redistributions of source code must retain the above copyright

 // notice, this list of conditions and the following disclaimer.

 //     * 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.

 //     * Neither the name of Google Inc. nor the names of its

 // contributors may be used to endorse or promote products derived from

 // this software without specific prior written permission.

 //

 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 // "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 THE COPYRIGHT

 // OWNER 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.

 // static_map.h: StaticMap.

 //

 // StaticMap provides lookup interfaces and iterators similar as stl::map's.

 // These lookup operations are purely Read-Only, thus memory

 // allocation & deallocation is mostly avoided (intentionally).

 //

 // The chunk of memory should contain data with pre-defined pattern:

 // **************** header ***************

 // uint32 (4 bytes): number of nodes

 // uint32 (4 bytes): address offset of node1's mapped_value

 // uint32 (4 bytes): address offset of node2's mapped_value

 // ...

 // uint32 (4 bytes): address offset of nodeN's mapped_value

 //

 // ************* Key array ************

 // (X bytes): node1's key

 // (X bytes): node2's key

 // ...

 // (X bytes): nodeN's key

 //

 // ************* Value array **********

 // (? bytes): node1's mapped_value

 // (? bytes): node2's mapped_value

 // ...

 // (? bytes): nodeN's mapped_value

 //

 // REQUIREMENT: Key type MUST be primitive type or pointers so that:

 // X = sizeof(typename Key);

 //

 // Note: since address offset is stored as uint32, user should keep in mind that

 // StaticMap only supports up to 4GB size of memory data.

 // Author: Siyang Xie (lambxsy@google.com)

 #ifndef PROCESSOR_STATIC_MAP_H__

 #define PROCESSOR_STATIC_MAP_H__

 #include "processor/static_map_iterator-inl.h"

 namespace google_breakpad {

 // Default functor to compare keys.

 template<typename Key>

 class DefaultCompare {

  public:

   int operator()(const Key &k1, const Key &k2) const {

     if (k1 < k2) return -1;

     if (k1 == k2) return 0;

     return 1;

   }

 };

 template<typename Key, typename Value, typename Compare = DefaultCompare<Key> >

 class StaticMap {

  public:

   typedef StaticMapIterator<Key, Value, Compare> iterator;

   typedef StaticMapIterator<Key, Value, Compare> const_iterator;

   StaticMap() : raw_data_(0),

                 num_nodes_(0),

                 offsets_(0),

                 compare_() { }

   explicit StaticMap(const char* raw_data);

   inline bool empty() const { return num_nodes_ == 0; }

   inline unsigned int size() const { return num_nodes_; }

   // Return iterators.

   inline iterator begin() const { return IteratorAtIndex(0); }

   inline iterator last() const { return IteratorAtIndex(num_nodes_ - 1); }

   inline iterator end() const { return IteratorAtIndex(num_nodes_); }

   inline iterator IteratorAtIndex(int index) const {

     return iterator(raw_data_, index);

   }

   // Lookup operations.

   iterator find(const Key &k) const;

   // lower_bound(k) searches in a sorted range for the first element that has a

   // key not less than the argument k.

   iterator lower_bound(const Key &k) const;

   // upper_bound(k) searches in a sorted range for the first element that has a

   // key greater than the argument k.

   iterator upper_bound(const Key &k) const;

   // Checks if the underlying memory data conforms to the predefined pattern:

   // first check the number of nodes is non-negative,

   // then check both offsets and keys are strictly increasing (sorted).

   bool ValidateInMemoryStructure() const;

  private:

   const Key GetKeyAtIndex(int i) const;

   // Start address of a raw memory chunk with serialized data.

   const char* raw_data_;

   // Number of nodes in the static map.

   int32_t num_nodes_;

   // Array of offset addresses for stored values.

   // For example:

   // address_of_i-th_node_value = raw_data_ + offsets_[i]

   const uint32_t* offsets_;

   // keys_[i] = key of i_th node

   const Key* keys_;

   Compare compare_;

 };

 }  // namespace google_breakpad

 #endif  // PROCESSOR_STATIC_MAP_H__