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 28  
 29  // static_map_iterator.h: StaticMapIterator template class declaration.
 30  //
 31  // StaticMapIterator provides increment and decrement operators to iterate
 32  // through a StaticMap map.  It does not provide *, -> operators, user should
 33  // use GetKeyPtr(), GetKey(), GetValuePtr() interfaces to retrieve data or
 34  // pointer to data.  StaticMapIterator is essentially a const_iterator.
 35  //
 36  // Author: Siyang Xie (lambxsy@google.com)
 37  
 38  
 39  #ifndef PROCESSOR_STATIC_MAP_ITERATOR_H__
 40  #define PROCESSOR_STATIC_MAP_ITERATOR_H__
 41  
 42  #include "google_breakpad/common/breakpad_types.h"
 43  
 44  namespace google_breakpad {
 45  
 46  // Forward declaration.
 47  template<typename Key, typename Value, typename Compare> class StaticMap;
 48  
 49  // StaticMapIterator does not support operator*() or operator->(),
 50  // User should use GetKey(), GetKeyPtr(), GetValuePtr() instead;
 51  template<typename Key, typename Value, typename Compare>
 52  class StaticMapIterator {
 53   public:
 54    // Constructors.
 55    StaticMapIterator(): index_(-1), base_(NULL) { }
 56  
 57    // Increment & Decrement operators:
 58    StaticMapIterator& operator++();
 59    StaticMapIterator operator++(int post_fix_operator);
 60  
 61    StaticMapIterator& operator--();
 62    StaticMapIterator operator--(int post_fix_operator);
 63  
 64    // Interface for retrieving data / pointer to data.
 65    const Key* GetKeyPtr() const;
 66  
 67    // Run time error will occur if GetKey() is called on an invalid iterator.
 68    inline const Key GetKey() const { return *GetKeyPtr(); }
 69  
 70    // return a raw memory pointer that points to the start address of value.
 71    const char* GetValueRawPtr() const;
 72  
 73    // return a reinterpret-casted pointer to the value.
 74    inline const Value* GetValuePtr() const {
 75      return reinterpret_cast<const Value*>(GetValueRawPtr());
 76    }
 77  
 78    bool operator==(const StaticMapIterator& x) const;
 79    bool operator!=(const StaticMapIterator& x) const;
 80  
 81    // Check if this iterator is valid.
 82    // If iterator is invalid, user is forbidden to use ++/-- operator
 83    // or interfaces for retrieving data / pointer to data.
 84    bool IsValid() const;
 85  
 86   private:
 87    friend class StaticMap<Key, Value, Compare>;
 88  
 89    // Only StaticMap can call this constructor.
 90    explicit StaticMapIterator(const char* base, const int32_t& index);
 91  
 92    // Index of node that the iterator is pointing to.
 93    int32_t index_;
 94  
 95    // Beginning address of the serialized map data.
 96    const char* base_;
 97  
 98    // Number of nodes in the map.  Use it to identify end() iterator.
 99    int32_t num_nodes_;
100  
101    // offsets_ is an array of offset addresses of mapped values.
102    // For example:
103    // address_of_i-th_node_value = base_ + offsets_[i]
104    const uint32_t* offsets_;
105  
106    // keys_[i] = key of i_th node.
107    const Key* keys_;
108  };
109  
110  }  // namespace google_breakpad
111  
112  #endif  // PROCESSOR_STATIC_MAP_ITERATOR_H__