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 // Copyright 2010 Google Inc. All Rights Reserved.

 //

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 // modification, are permitted provided that the following conditions are

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 //

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

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 //     * Redistributions in binary form must reproduce the above

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 // in the documentation and/or other materials provided with the

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 // 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

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 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 // static_map-inl.h: StaticMap implementation.

 //

 // See static_map.h for documentation.

 //

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

 #ifndef PROCESSOR_STATIC_MAP_INL_H__

 #define PROCESSOR_STATIC_MAP_INL_H__

 #include "processor/static_map.h"

 #include "processor/static_map_iterator-inl.h"

 #include "common/logging.h"

 namespace google_breakpad {

 template<typename Key, typename Value, typename Compare>

 StaticMap<Key, Value, Compare>::StaticMap(const char* raw_data)

     : raw_data_(raw_data),

       compare_() {

   // First 4 Bytes store the number of nodes.

   num_nodes_ = *(reinterpret_cast<const uint32_t*>(raw_data_));

   offsets_ = reinterpret_cast<const uint32_t*>(

       raw_data_ + sizeof(num_nodes_));

   keys_ = reinterpret_cast<const Key*>(

       raw_data_ + (1 + num_nodes_) * sizeof(uint32_t));

 }

 // find(), lower_bound() and upper_bound() implement binary search algorithm.

 template<typename Key, typename Value, typename Compare>

 StaticMapIterator<Key, Value, Compare>

 StaticMap<Key, Value, Compare>::find(const Key &key) const {

   int begin = 0;

   int end = num_nodes_;

   int middle;

   int compare_result;

   while (begin < end) {

     middle = begin + (end - begin) / 2;

     compare_result = compare_(key, GetKeyAtIndex(middle));

     if (compare_result == 0)

       return IteratorAtIndex(middle);

     if (compare_result < 0) {

       end = middle;

     } else {

       begin = middle + 1;

     }

   }

   return this->end();

 }

 template<typename Key, typename Value, typename Compare>

 StaticMapIterator<Key, Value, Compare>

 StaticMap<Key, Value, Compare>::lower_bound(const Key &key) const {

   int begin = 0;

   int end = num_nodes_;

   int middle;

   int comp_result;

   while (begin < end) {

     middle = begin + (end - begin) / 2;

     comp_result = compare_(key, GetKeyAtIndex(middle));

     if (comp_result == 0)

       return IteratorAtIndex(middle);

     if (comp_result < 0) {

       end = middle;

     } else {

       begin = middle + 1;

     }

   }

   return IteratorAtIndex(begin);

 }

 template<typename Key, typename Value, typename Compare>

 StaticMapIterator<Key, Value, Compare>

 StaticMap<Key, Value, Compare>::upper_bound(const Key &key) const {

   int begin = 0;

   int end = num_nodes_;

   int middle;

   int compare_result;

   while (begin < end) {

     middle = begin + (end - begin) / 2;

     compare_result = compare_(key, GetKeyAtIndex(middle));

     if (compare_result == 0)

       return IteratorAtIndex(middle + 1);

     if (compare_result < 0) {

       end = middle;

     } else {

       begin = middle + 1;

     }

   }

   return IteratorAtIndex(begin);

 }

 template<typename Key, typename Value, typename Compare>

 bool StaticMap<Key, Value, Compare>::ValidateInMemoryStructure() const {

   // check the number of nodes is non-negative:

   if (!raw_data_) return false;

   int32_t num_nodes = *(reinterpret_cast<const int32_t*>(raw_data_));

   if (num_nodes < 0) {

     BPLOG(INFO) << "StaticMap check failed: negative number of nodes";

     return false;

   }

   int node_index = 0;

   if (num_nodes_) {

     uint64_t first_offset = sizeof(int32_t) * (num_nodes_ + 1)

                            + sizeof(Key) * num_nodes_;

     // Num_nodes_ is too large.

     if (first_offset > 0xffffffffUL) {

       BPLOG(INFO) << "StaticMap check failed: size exceeds limit";

       return false;

     }

     if (offsets_[node_index] != static_cast<uint32_t>(first_offset)) {

       BPLOG(INFO) << "StaticMap check failed: first node offset is incorrect";

       return false;

     }

   }

   for (node_index = 1; node_index < num_nodes_; ++node_index) {

     // Check offsets[i] is strictly increasing:

     if (offsets_[node_index] <= offsets_[node_index - 1]) {

       BPLOG(INFO) << "StaticMap check failed: node offsets non-increasing";

       return false;

     }

     // Check Key[i] is strictly increasing as no duplicate keys are allowed.

     if (compare_(GetKeyAtIndex(node_index),

                  GetKeyAtIndex(node_index - 1)) <= 0) {

       BPLOG(INFO) << "StaticMap check failed: node keys non-increasing";

       return false;

     }

   }

   return true;

 }

 template<typename Key, typename Value, typename Compare>

 const Key StaticMap<Key, Value, Compare>::GetKeyAtIndex(int index) const {

   if (index < 0 || index >= num_nodes_) {

     BPLOG(ERROR) << "Key index out of range error";

     // Key type is required to be primitive type.  Return 0 if index is invalid.

     return 0;

   }

   return keys_[index];

 }

 }  // namespace google_breakpad

 #endif  // PROCESSOR_STATIC_MAP_INL_H__