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Diffstat (limited to 'toolkit/crashreporter/google-breakpad/src/processor/range_map.h')
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diff --git a/toolkit/crashreporter/google-breakpad/src/processor/range_map.h b/toolkit/crashreporter/google-breakpad/src/processor/range_map.h new file mode 100644 index 000000000..d90a67327 --- /dev/null +++ b/toolkit/crashreporter/google-breakpad/src/processor/range_map.h @@ -0,0 +1,161 @@ +// 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() : enable_shrink_down_(false), map_() {} + + // |enable_shrink_down| tells whether overlapping ranges can be shrunk down. + // If true, then adding a new range that overlaps with an existing one can + // be a successful operation. The range which ends at the higher address + // will be shrunk down by moving its start position to a higher address so + // that it does not overlap anymore. + void SetEnableShrinkDown(bool enable_shrink_down); + bool IsShrinkDownEnabled() const; + + // 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. If enable_shrink_down is true and there is an overlap + // between the current range and some other range (already in the map), + // shrink down the range which ends at a higher address. + 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, entry_delta, and entry_size, if + // non-NULL, are set to the base, delta, and size of the entry's range. + // A positive entry delta (> 0) indicates that there was an overlap and the + // entry was shrunk down (original start address was increased by delta). + bool RetrieveRange(const AddressType &address, EntryType *entry, + AddressType *entry_base, AddressType *entry_delta, + 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, entry_delta, and entry_size, + // if non-NULL, are set to the base, delta, and size of the entry's range. + // A positive entry delta (> 0) indicates that there was an overlap and the + // entry was shrunk down (original start address was increased by delta). + bool RetrieveNearestRange(const AddressType &address, EntryType *entry, + AddressType *entry_base, AddressType *entry_delta, + 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, + // entry_delta, and entry_size, if non-NULL, are set to the base, delta, and + // size of the entry's range. + // A positive entry delta (> 0) indicates that there was an overlap and the + // entry was shrunk down (original start address was increased by delta). + // + // RetrieveRangeAtIndex is not optimized for speedy operation. + bool RetrieveRangeAtIndex(int index, EntryType *entry, + AddressType *entry_base, AddressType *entry_delta, + 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>; + + // Same a StoreRange() with the only exception that the |delta| can be + // passed in. + bool StoreRangeInternal(const AddressType &base, const AddressType &delta, + const AddressType &size, const EntryType &entry); + + class Range { + public: + Range(const AddressType &base, const AddressType &delta, + const EntryType &entry) + : base_(base), delta_(delta), entry_(entry) {} + + AddressType base() const { return base_; } + AddressType delta() const { return delta_; } + 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 delta when the range is shrunk down. + const AddressType delta_; + + // 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; + + // Whether overlapping ranges can be shrunk down. + bool enable_shrink_down_; + + // Maps the high address of each range to a EntryType. + AddressToRangeMap map_; +}; + + +} // namespace google_breakpad + + +#endif // PROCESSOR_RANGE_MAP_H__ |