michael@0: // Copyright (c) 2010 Google Inc.
michael@0: // All rights reserved.
michael@0: //
michael@0: // Redistribution and use in source and binary forms, with or without
michael@0: // modification, are permitted provided that the following conditions are
michael@0: // met:
michael@0: //
michael@0: //     * Redistributions of source code must retain the above copyright
michael@0: // notice, this list of conditions and the following disclaimer.
michael@0: //     * Redistributions in binary form must reproduce the above
michael@0: // copyright notice, this list of conditions and the following disclaimer
michael@0: // in the documentation and/or other materials provided with the
michael@0: // distribution.
michael@0: //     * Neither the name of Google Inc. nor the names of its
michael@0: // contributors may be used to endorse or promote products derived from
michael@0: // this software without specific prior written permission.
michael@0: //
michael@0: // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0: // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0: // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
michael@0: // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
michael@0: // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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michael@0: // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
michael@0: // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
michael@0: // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
michael@0: // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
michael@0: // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0: 
michael@0: // range_map-inl.h: Range map implementation.
michael@0: //
michael@0: // See range_map.h for documentation.
michael@0: //
michael@0: // Author: Mark Mentovai
michael@0: 
michael@0: #ifndef PROCESSOR_RANGE_MAP_INL_H__
michael@0: #define PROCESSOR_RANGE_MAP_INL_H__
michael@0: 
michael@0: 
michael@0: #include <assert.h>
michael@0: 
michael@0: #include "processor/range_map.h"
michael@0: #include "common/logging.h"
michael@0: 
michael@0: 
michael@0: namespace google_breakpad {
michael@0: 
michael@0: 
michael@0: template<typename AddressType, typename EntryType>
michael@0: bool RangeMap<AddressType, EntryType>::StoreRange(const AddressType &base,
michael@0:                                                   const AddressType &size,
michael@0:                                                   const EntryType &entry) {
michael@0:   AddressType high = base + size - 1;
michael@0: 
michael@0:   // Check for undersize or overflow.
michael@0:   if (size <= 0 || high < base) {
michael@0:     // The processor will hit this case too frequently with common symbol
michael@0:     // files in the size == 0 case, which is more suited to a DEBUG channel.
michael@0:     // Filter those out since there's no DEBUG channel at the moment.
michael@0:     BPLOG_IF(INFO, size != 0) << "StoreRange failed, " << HexString(base) <<
michael@0:                                  "+" << HexString(size) << ", " <<
michael@0:                                  HexString(high);
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   // Ensure that this range does not overlap with another one already in the
michael@0:   // map.
michael@0:   MapConstIterator iterator_base = map_.lower_bound(base);
michael@0:   MapConstIterator iterator_high = map_.lower_bound(high);
michael@0: 
michael@0:   if (iterator_base != iterator_high) {
michael@0:     // Some other range begins in the space used by this range.  It may be
michael@0:     // contained within the space used by this range, or it may extend lower.
michael@0:     // Regardless, it is an error.
michael@0:     AddressType other_base = iterator_base->second.base();
michael@0:     AddressType other_size = iterator_base->first - other_base + 1;
michael@0:     BPLOG(INFO) << "StoreRange failed, an existing range is contained by or "
michael@0:                    "extends lower than the new range: new " <<
michael@0:                    HexString(base) << "+" << HexString(size) << ", existing " <<
michael@0:                    HexString(other_base) << "+" << HexString(other_size);
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   if (iterator_high != map_.end()) {
michael@0:     if (iterator_high->second.base() <= high) {
michael@0:       // The range above this one overlaps with this one.  It may fully
michael@0:       // contain this range, or it may begin within this range and extend
michael@0:       // higher.  Regardless, it's an error.
michael@0:       AddressType other_base = iterator_high->second.base();
michael@0:       AddressType other_size = iterator_high->first - other_base + 1;
michael@0:       BPLOG(INFO) << "StoreRange failed, an existing range contains or "
michael@0:                      "extends higher than the new range: new " <<
michael@0:                      HexString(base) << "+" << HexString(size) <<
michael@0:                      ", existing " <<
michael@0:                      HexString(other_base) << "+" << HexString(other_size);
michael@0:       return false;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // Store the range in the map by its high address, so that lower_bound can
michael@0:   // be used to quickly locate a range by address.
michael@0:   map_.insert(MapValue(high, Range(base, entry)));
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: 
michael@0: template<typename AddressType, typename EntryType>
michael@0: bool RangeMap<AddressType, EntryType>::RetrieveRange(
michael@0:     const AddressType &address, EntryType *entry,
michael@0:     AddressType *entry_base, AddressType *entry_size) const {
michael@0:   BPLOG_IF(ERROR, !entry) << "RangeMap::RetrieveRange requires |entry|";
michael@0:   assert(entry);
michael@0: 
michael@0:   MapConstIterator iterator = map_.lower_bound(address);
michael@0:   if (iterator == map_.end())
michael@0:     return false;
michael@0: 
michael@0:   // The map is keyed by the high address of each range, so |address| is
michael@0:   // guaranteed to be lower than the range's high address.  If |range| is
michael@0:   // not directly preceded by another range, it's possible for address to
michael@0:   // be below the range's low address, though.  When that happens, address
michael@0:   // references something not within any range, so return false.
michael@0:   if (address < iterator->second.base())
michael@0:     return false;
michael@0: 
michael@0:   *entry = iterator->second.entry();
michael@0:   if (entry_base)
michael@0:     *entry_base = iterator->second.base();
michael@0:   if (entry_size)
michael@0:     *entry_size = iterator->first - iterator->second.base() + 1;
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: 
michael@0: template<typename AddressType, typename EntryType>
michael@0: bool RangeMap<AddressType, EntryType>::RetrieveNearestRange(
michael@0:     const AddressType &address, EntryType *entry,
michael@0:     AddressType *entry_base, AddressType *entry_size) const {
michael@0:   BPLOG_IF(ERROR, !entry) << "RangeMap::RetrieveNearestRange requires |entry|";
michael@0:   assert(entry);
michael@0: 
michael@0:   // If address is within a range, RetrieveRange can handle it.
michael@0:   if (RetrieveRange(address, entry, entry_base, entry_size))
michael@0:     return true;
michael@0: 
michael@0:   // upper_bound gives the first element whose key is greater than address,
michael@0:   // but we want the first element whose key is less than or equal to address.
michael@0:   // Decrement the iterator to get there, but not if the upper_bound already
michael@0:   // points to the beginning of the map - in that case, address is lower than
michael@0:   // the lowest stored key, so return false.
michael@0:   MapConstIterator iterator = map_.upper_bound(address);
michael@0:   if (iterator == map_.begin())
michael@0:     return false;
michael@0:   --iterator;
michael@0: 
michael@0:   *entry = iterator->second.entry();
michael@0:   if (entry_base)
michael@0:     *entry_base = iterator->second.base();
michael@0:   if (entry_size)
michael@0:     *entry_size = iterator->first - iterator->second.base() + 1;
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: 
michael@0: template<typename AddressType, typename EntryType>
michael@0: bool RangeMap<AddressType, EntryType>::RetrieveRangeAtIndex(
michael@0:     int index, EntryType *entry,
michael@0:     AddressType *entry_base, AddressType *entry_size) const {
michael@0:   BPLOG_IF(ERROR, !entry) << "RangeMap::RetrieveRangeAtIndex requires |entry|";
michael@0:   assert(entry);
michael@0: 
michael@0:   if (index >= GetCount()) {
michael@0:     BPLOG(ERROR) << "Index out of range: " << index << "/" << GetCount();
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   // Walk through the map.  Although it's ordered, it's not a vector, so it
michael@0:   // can't be addressed directly by index.
michael@0:   MapConstIterator iterator = map_.begin();
michael@0:   for (int this_index = 0; this_index < index; ++this_index)
michael@0:     ++iterator;
michael@0: 
michael@0:   *entry = iterator->second.entry();
michael@0:   if (entry_base)
michael@0:     *entry_base = iterator->second.base();
michael@0:   if (entry_size)
michael@0:     *entry_size = iterator->first - iterator->second.base() + 1;
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: 
michael@0: template<typename AddressType, typename EntryType>
michael@0: int RangeMap<AddressType, EntryType>::GetCount() const {
michael@0:   return map_.size();
michael@0: }
michael@0: 
michael@0: 
michael@0: template<typename AddressType, typename EntryType>
michael@0: void RangeMap<AddressType, EntryType>::Clear() {
michael@0:   map_.clear();
michael@0: }
michael@0: 
michael@0: 
michael@0: }  // namespace google_breakpad
michael@0: 
michael@0: 
michael@0: #endif  // PROCESSOR_RANGE_MAP_INL_H__