static_contained_range_map-inl.h

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// static_contained_range_map-inl.h: Hierarchically-organized range map,
// i.e., StaticContainedRangeMap implementation.
//
// See static_contained_range_map.h for documentation.
//
// Author: Siyang Xie (lambxsy@google.com)

#ifndef PROCESSOR_STATIC_CONTAINED_RANGE_MAP_INL_H__
#define PROCESSOR_STATIC_CONTAINED_RANGE_MAP_INL_H__

#include "processor/static_contained_range_map.h"
#include "processor/logging.h"

namespace google_breakpad {

template<typename AddressType, typename EntryType>
StaticContainedRangeMap<AddressType, EntryType>::StaticContainedRangeMap(
    const char *base)
    : base_(*(reinterpret_cast<const AddressType*>(base))),
      entry_size_(*(reinterpret_cast<const uint32_t*>(base + sizeof(base_)))),
      entry_ptr_(reinterpret_cast<const EntryType *>(
          base + sizeof(base_) + sizeof(entry_size_))),
      map_(base + sizeof(base_) + sizeof(entry_size_) + entry_size_) {
  if (entry_size_ == 0)
    entry_ptr_ = NULL;
}


template<typename AddressType, typename EntryType>
bool StaticContainedRangeMap<AddressType, EntryType>::RetrieveRange(
    const AddressType &address, const EntryType *&entry) const {

  // 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())
    return false;

  const char *memory_child =
      reinterpret_cast<const char*>(iterator.GetValuePtr());

  StaticContainedRangeMap child_map(memory_child);

  if (address < child_map.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 (!child_map.RetrieveRange(address, entry))
    entry = child_map.entry_ptr_;

  return true;
}

}  // namespace google_breakpad

#endif  // PROCESSOR_STATIC_CONTAINED_RANGE_MAP_INL_H__