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 // Copyright (c) 2006, 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.

 // range_map.h: Range maps.

 //

 // A range map associates a range of addresses with a specific object.  This

 // is useful when certain objects of variable size are located within an

 // address space.  The range map makes it simple to determine which object is

 // associated with a specific address, which may be any address within the

 // range associated with an object.

 //

 // Author: Mark Mentovai

 #ifndef PROCESSOR_RANGE_MAP_H__

 #define PROCESSOR_RANGE_MAP_H__

 #include <map>

 namespace google_breakpad {

 // Forward declarations (for later friend declarations of specialized template).

 template<class, class> class RangeMapSerializer;

 template<typename AddressType, typename EntryType>

 class RangeMap {

  public:

   RangeMap() : map_() {}

   // Inserts a range into the map.  Returns false for a parameter error,

   // or if the location of the range would conflict with a range already

   // stored in the map.

   bool StoreRange(const AddressType &base,

                   const AddressType &size,

                   const EntryType &entry);

   // Locates the range encompassing the supplied address.  If there is

   // no such range, returns false.  entry_base and entry_size, if non-NULL,

   // are set to the base and size of the entry's range.

   bool RetrieveRange(const AddressType &address, EntryType *entry,

                      AddressType *entry_base, AddressType *entry_size) const;

   // Locates the range encompassing the supplied address, if one exists.

   // If no range encompasses the supplied address, locates the nearest range

   // to the supplied address that is lower than the address.  Returns false

   // if no range meets these criteria.  entry_base and entry_size, if

   // non-NULL, are set to the base and size of the entry's range.

   bool RetrieveNearestRange(const AddressType &address, EntryType *entry,

                             AddressType *entry_base, AddressType *entry_size)

                             const;

   // Treating all ranges as a list ordered by the address spaces that they

   // occupy, locates the range at the index specified by index.  Returns

   // false if index is larger than the number of ranges stored.  entry_base

   // and entry_size, if non-NULL, are set to the base and size of the entry's

   // range.

   //

   // RetrieveRangeAtIndex is not optimized for speedy operation.

   bool RetrieveRangeAtIndex(int index, EntryType *entry,

                             AddressType *entry_base, AddressType *entry_size)

                             const;

   // Returns the number of ranges stored in the RangeMap.

   int GetCount() const;

   // Empties the range map, restoring it to the state it was when it was

   // initially created.

   void Clear();

  private:

   // Friend declarations.

   friend class ModuleComparer;

   friend class RangeMapSerializer<AddressType, EntryType>;

   class Range {

    public:

     Range(const AddressType &base, const EntryType &entry)

         : base_(base), entry_(entry) {}

     AddressType base() const { return base_; }

     EntryType entry() const { return entry_; }

    private:

     // The base address of the range.  The high address does not need to

     // be stored, because RangeMap uses it as the key to the map.

     const AddressType base_;

     // The entry corresponding to a range.

     const EntryType entry_;

   };

   // Convenience types.

   typedef std::map<AddressType, Range> AddressToRangeMap;

   typedef typename AddressToRangeMap::const_iterator MapConstIterator;

   typedef typename AddressToRangeMap::value_type MapValue;

   // Maps the high address of each range to a EntryType.

   AddressToRangeMap map_;

 };

 }  // namespace google_breakpad

 #endif  // PROCESSOR_RANGE_MAP_H__