/thirdparty/breakpad/processor/static_contained_range_map-inl.h

 1// Copyright (c) 2010, Google Inc.
 2// All rights reserved.
 3//
 4// Redistribution and use in source and binary forms, with or without
 5// modification, are permitted provided that the following conditions are
 6// met:
 7//
 8//     * Redistributions of source code must retain the above copyright
 9// notice, this list of conditions and the following disclaimer.
10//     * Redistributions in binary form must reproduce the above
11// copyright notice, this list of conditions and the following disclaimer
12// in the documentation and/or other materials provided with the
13// distribution.
14//     * Neither the name of Google Inc. nor the names of its
15// contributors may be used to endorse or promote products derived from
16// this software without specific prior written permission.
17//
18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30// static_contained_range_map-inl.h: Hierarchically-organized range map,
31// i.e., StaticContainedRangeMap implementation.
32//
33// See static_contained_range_map.h for documentation.
34//
35// Author: Siyang Xie (lambxsy@google.com)
36
37#ifndef PROCESSOR_STATIC_CONTAINED_RANGE_MAP_INL_H__
38#define PROCESSOR_STATIC_CONTAINED_RANGE_MAP_INL_H__
39
40#include "processor/static_contained_range_map.h"
41#include "processor/logging.h"
42
43namespace google_breakpad {
44
45template<typename AddressType, typename EntryType>
46StaticContainedRangeMap<AddressType, EntryType>::StaticContainedRangeMap(
47    const char *base)
48    : base_(*(reinterpret_cast<const AddressType*>(base))),
49      entry_size_(*(reinterpret_cast<const u_int32_t*>(base + sizeof(base_)))),
50      entry_ptr_(reinterpret_cast<const EntryType *>(
51          base + sizeof(base_) + sizeof(entry_size_))),
52      map_(base + sizeof(base_) + sizeof(entry_size_) + entry_size_) {
53  if (entry_size_ == 0)
54    entry_ptr_ = NULL;
55}
56
57
58template<typename AddressType, typename EntryType>
59bool StaticContainedRangeMap<AddressType, EntryType>::RetrieveRange(
60    const AddressType &address, const EntryType *&entry) const {
61
62  // Get an iterator to the child range whose high address is equal to or
63  // greater than the supplied address.  If the supplied address is higher
64  // than all of the high addresses in the range, then this range does not
65  // contain a child at address, so return false.  If the supplied address
66  // is lower than the base address of the child range, then it is not within
67  // the child range, so return false.
68  MapConstIterator iterator = map_.lower_bound(address);
69
70  if (iterator == map_.end())
71    return false;
72
73  const char *memory_child =
74      reinterpret_cast<const char*>(iterator.GetValuePtr());
75
76  StaticContainedRangeMap child_map(memory_child);
77
78  if (address < child_map.base_)
79    return false;
80
81  // The child in iterator->second contains the specified address.  Find out
82  // if it has a more-specific descendant that also contains it.  If it does,
83  // it will set |entry| appropriately.  If not, set |entry| to the child.
84  if (!child_map.RetrieveRange(address, entry))
85    entry = child_map.entry_ptr_;
86
87  return true;
88}
89
90}  // namespace google_breakpad
91
92#endif  // PROCESSOR_STATIC_CONTAINED_RANGE_MAP_INL_H__