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 // Copyright (c) 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.

 // range_map-inl.h: Range map implementation.

 //

 // See range_map.h for documentation.

 //

 // Author: Mark Mentovai

 #ifndef PROCESSOR_RANGE_MAP_INL_H__

 #define PROCESSOR_RANGE_MAP_INL_H__

 #include <assert.h>

 #include "processor/range_map.h"

 #include "common/logging.h"

 namespace google_breakpad {

 template<typename AddressType, typename EntryType>

 bool RangeMap<AddressType, EntryType>::StoreRange(const AddressType &base,

                                                   const AddressType &size,

                                                   const EntryType &entry) {

   AddressType high = base + size - 1;

   // Check for undersize or overflow.

   if (size <= 0 || high < base) {

     // The processor will hit this case too frequently with common symbol

     // files in the size == 0 case, which is more suited to a DEBUG channel.

     // Filter those out since there's no DEBUG channel at the moment.

     BPLOG_IF(INFO, size != 0) << "StoreRange failed, " << HexString(base) <<

                                  "+" << HexString(size) << ", " <<

                                  HexString(high);

     return false;

   }

   // Ensure that this range does not overlap with another one already in the

   // map.

   MapConstIterator iterator_base = map_.lower_bound(base);

   MapConstIterator iterator_high = map_.lower_bound(high);

   if (iterator_base != iterator_high) {

     // Some other range begins in the space used by this range.  It may be

     // contained within the space used by this range, or it may extend lower.

     // Regardless, it is an error.

     AddressType other_base = iterator_base->second.base();

     AddressType other_size = iterator_base->first - other_base + 1;

     BPLOG(INFO) << "StoreRange failed, an existing range is contained by or "

                    "extends lower than the new range: new " <<

                    HexString(base) << "+" << HexString(size) << ", existing " <<

                    HexString(other_base) << "+" << HexString(other_size);

     return false;

   }

   if (iterator_high != map_.end()) {

     if (iterator_high->second.base() <= high) {

       // The range above this one overlaps with this one.  It may fully

       // contain this range, or it may begin within this range and extend

       // higher.  Regardless, it's an error.

       AddressType other_base = iterator_high->second.base();

       AddressType other_size = iterator_high->first - other_base + 1;

       BPLOG(INFO) << "StoreRange failed, an existing range contains or "

                      "extends higher than the new range: new " <<

                      HexString(base) << "+" << HexString(size) <<

                      ", existing " <<

                      HexString(other_base) << "+" << HexString(other_size);

       return false;

     }

   }

   // Store the range in the map by its high address, so that lower_bound can

   // be used to quickly locate a range by address.

   map_.insert(MapValue(high, Range(base, entry)));

   return true;

 }

 template<typename AddressType, typename EntryType>

 bool RangeMap<AddressType, EntryType>::RetrieveRange(

     const AddressType &address, EntryType *entry,

     AddressType *entry_base, AddressType *entry_size) const {

   BPLOG_IF(ERROR, !entry) << "RangeMap::RetrieveRange requires |entry|";

   assert(entry);

   MapConstIterator iterator = map_.lower_bound(address);

   if (iterator == map_.end())

     return false;

   // The map is keyed by the high address of each range, so |address| is

   // guaranteed to be lower than the range's high address.  If |range| is

   // not directly preceded by another range, it's possible for address to

   // be below the range's low address, though.  When that happens, address

   // references something not within any range, so return false.

   if (address < iterator->second.base())

     return false;

   *entry = iterator->second.entry();

   if (entry_base)

     *entry_base = iterator->second.base();

   if (entry_size)

     *entry_size = iterator->first - iterator->second.base() + 1;

   return true;

 }

 template<typename AddressType, typename EntryType>

 bool RangeMap<AddressType, EntryType>::RetrieveNearestRange(

     const AddressType &address, EntryType *entry,

     AddressType *entry_base, AddressType *entry_size) const {

   BPLOG_IF(ERROR, !entry) << "RangeMap::RetrieveNearestRange requires |entry|";

   assert(entry);

   // If address is within a range, RetrieveRange can handle it.

   if (RetrieveRange(address, entry, entry_base, entry_size))

     return true;

   // upper_bound gives the first element whose key is greater than address,

   // but we want the first element whose key is less than or equal to address.

   // Decrement the iterator to get there, but not if the upper_bound already

   // points to the beginning of the map - in that case, address is lower than

   // the lowest stored key, so return false.

   MapConstIterator iterator = map_.upper_bound(address);

   if (iterator == map_.begin())

     return false;

   --iterator;

   *entry = iterator->second.entry();

   if (entry_base)

     *entry_base = iterator->second.base();

   if (entry_size)

     *entry_size = iterator->first - iterator->second.base() + 1;

   return true;

 }

 template<typename AddressType, typename EntryType>

 bool RangeMap<AddressType, EntryType>::RetrieveRangeAtIndex(

     int index, EntryType *entry,

     AddressType *entry_base, AddressType *entry_size) const {

   BPLOG_IF(ERROR, !entry) << "RangeMap::RetrieveRangeAtIndex requires |entry|";

   assert(entry);

   if (index >= GetCount()) {

     BPLOG(ERROR) << "Index out of range: " << index << "/" << GetCount();

     return false;

   }

   // Walk through the map.  Although it's ordered, it's not a vector, so it

   // can't be addressed directly by index.

   MapConstIterator iterator = map_.begin();

   for (int this_index = 0; this_index < index; ++this_index)

     ++iterator;

   *entry = iterator->second.entry();

   if (entry_base)

     *entry_base = iterator->second.base();

   if (entry_size)

     *entry_size = iterator->first - iterator->second.base() + 1;

   return true;

 }

 template<typename AddressType, typename EntryType>

 int RangeMap<AddressType, EntryType>::GetCount() const {

   return map_.size();

 }

 template<typename AddressType, typename EntryType>

 void RangeMap<AddressType, EntryType>::Clear() {

   map_.clear();

 }

 }  // namespace google_breakpad

 #endif  // PROCESSOR_RANGE_MAP_INL_H__