/thirdparty/breakpad/processor/contained_range_map-inl.h
http://github.com/tomahawk-player/tomahawk · C++ Header · 197 lines · 73 code · 37 blank · 87 comment · 27 complexity · 95c664b914b01996cc917fafb04c768a MD5 · raw file
- // 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.
- // contained_range_map-inl.h: Hierarchically-organized range map implementation.
- //
- // See contained_range_map.h for documentation.
- //
- // Author: Mark Mentovai
- #ifndef PROCESSOR_CONTAINED_RANGE_MAP_INL_H__
- #define PROCESSOR_CONTAINED_RANGE_MAP_INL_H__
- #include "processor/contained_range_map.h"
- #include <assert.h>
- #include "processor/logging.h"
- namespace google_breakpad {
- template<typename AddressType, typename EntryType>
- ContainedRangeMap<AddressType, EntryType>::~ContainedRangeMap() {
- // Clear frees the children pointed to by the map, and frees the map itself.
- Clear();
- }
- template<typename AddressType, typename EntryType>
- bool ContainedRangeMap<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) {
- //TODO(nealsid) We are commenting this out in order to prevent
- // excessive logging. We plan to move to better logging as this
- // failure happens quite often and is expected(see comment in
- // basic_source_line_resolver.cc:671).
- // BPLOG(INFO) << "StoreRange failed, " << HexString(base) << "+"
- // << HexString(size) << ", " << HexString(high);
- return false;
- }
- if (!map_)
- map_ = new AddressToRangeMap();
- MapIterator iterator_base = map_->lower_bound(base);
- MapIterator iterator_high = map_->lower_bound(high);
- MapIterator iterator_end = map_->end();
- if (iterator_base == iterator_high && iterator_base != iterator_end &&
- base >= iterator_base->second->base_) {
- // The new range is entirely within an existing child range.
- // If the new range's geometry is exactly equal to an existing child
- // range's, it violates the containment rules, and an attempt to store
- // it must fail. iterator_base->first contains the key, which was the
- // containing child's high address.
- if (iterator_base->second->base_ == base && iterator_base->first == high) {
- // TODO(nealsid): See the TODO above on why this is commented out.
- // BPLOG(INFO) << "StoreRange failed, identical range is already "
- // "present: " << HexString(base) << "+" << HexString(size);
- return false;
- }
- // Pass the new range on to the child to attempt to store.
- return iterator_base->second->StoreRange(base, size, entry);
- }
- // iterator_high might refer to an irrelevant range: one whose base address
- // is higher than the new range's high address. Set contains_high to true
- // only if iterator_high refers to a range that is at least partially
- // within the new range.
- bool contains_high = iterator_high != iterator_end &&
- high >= iterator_high->second->base_;
- // If the new range encompasses any existing child ranges, it must do so
- // fully. Partial containment isn't allowed.
- if ((iterator_base != iterator_end && base > iterator_base->second->base_) ||
- (contains_high && high < iterator_high->first)) {
- // TODO(mmentovai): Some symbol files will trip this check frequently
- // on STACK lines. Too many messages will be produced. These are more
- // suitable for a DEBUG channel than an INFO channel.
- // BPLOG(INFO) << "StoreRange failed, new range partially contains "
- // "existing range: " << HexString(base) << "+" <<
- // HexString(size);
- return false;
- }
- // When copying and erasing contained ranges, the "end" iterator needs to
- // point one past the last item of the range to copy. If contains_high is
- // false, the iterator's already in the right place; the increment is safe
- // because contains_high can't be true if iterator_high == iterator_end.
- if (contains_high)
- ++iterator_high;
- // Optimization: if the iterators are equal, no child ranges would be
- // moved. Create the new child range with a NULL map to conserve space
- // in leaf nodes, of which there will be many.
- AddressToRangeMap *child_map = NULL;
- if (iterator_base != iterator_high) {
- // The children of this range that are contained by the new range must
- // be transferred over to the new range. Create the new child range map
- // and copy the pointers to range maps it should contain into it.
- child_map = new AddressToRangeMap(iterator_base, iterator_high);
- // Remove the copied child pointers from this range's map of children.
- map_->erase(iterator_base, iterator_high);
- }
- // Store the new range in the map by its high address. Any children that
- // the new child range contains were formerly children of this range but
- // are now this range's grandchildren. Ownership of these is transferred
- // to the new child range.
- map_->insert(MapValue(high,
- new ContainedRangeMap(base, entry, child_map)));
- return true;
- }
- template<typename AddressType, typename EntryType>
- bool ContainedRangeMap<AddressType, EntryType>::RetrieveRange(
- const AddressType &address, EntryType *entry) const {
- BPLOG_IF(ERROR, !entry) << "ContainedRangeMap::RetrieveRange requires "
- "|entry|";
- assert(entry);
- // If nothing was ever stored, then there's nothing to retrieve.
- if (!map_)
- return false;
- // Get an iterator to the child range whose high address is equal to or
- // greater than the supplied address. If the supplied address is higher
- // than all of the high addresses in the range, then this range does not
- // contain a child at address, so return false. If the supplied address
- // is lower than the base address of the child range, then it is not within
- // the child range, so return false.
- MapConstIterator iterator = map_->lower_bound(address);
- if (iterator == map_->end() || address < iterator->second->base_)
- return false;
- // The child in iterator->second contains the specified address. Find out
- // if it has a more-specific descendant that also contains it. If it does,
- // it will set |entry| appropriately. If not, set |entry| to the child.
- if (!iterator->second->RetrieveRange(address, entry))
- *entry = iterator->second->entry_;
- return true;
- }
- template<typename AddressType, typename EntryType>
- void ContainedRangeMap<AddressType, EntryType>::Clear() {
- if (map_) {
- MapConstIterator end = map_->end();
- for (MapConstIterator child = map_->begin(); child != end; ++child)
- delete child->second;
- delete map_;
- map_ = NULL;
- }
- }
- } // namespace google_breakpad
- #endif // PROCESSOR_CONTAINED_RANGE_MAP_INL_H__