/thirdparty/breakpad/processor/static_map.h
C++ Header | 144 lines | 45 code | 24 blank | 75 comment | 4 complexity | 363d3a8e5286daaab1572ac08d1e14e4 MD5 | raw file
1// Copyright 2010 Google Inc. All Rights Reserved. 2// 3// Redistribution and use in source and binary forms, with or without 4// modification, are permitted provided that the following conditions are 5// met: 6// 7// * Redistributions of source code must retain the above copyright 8// notice, this list of conditions and the following disclaimer. 9// * Redistributions in binary form must reproduce the above 10// copyright notice, this list of conditions and the following disclaimer 11// in the documentation and/or other materials provided with the 12// distribution. 13// * Neither the name of Google Inc. nor the names of its 14// contributors may be used to endorse or promote products derived from 15// this software without specific prior written permission. 16// 17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 29// static_map.h: StaticMap. 30// 31// StaticMap provides lookup interfaces and iterators similar as stl::map's. 32// These lookup operations are purely Read-Only, thus memory 33// allocation & deallocation is mostly avoided (intentionally). 34// 35// The chunk of memory should contain data with pre-defined pattern: 36// **************** header *************** 37// uint32 (4 bytes): number of nodes 38// uint32 (4 bytes): address offset of node1's mapped_value 39// uint32 (4 bytes): address offset of node2's mapped_value 40// ... 41// uint32 (4 bytes): address offset of nodeN's mapped_value 42// 43// ************* Key array ************ 44// (X bytes): node1's key 45// (X bytes): node2's key 46// ... 47// (X bytes): nodeN's key 48// 49// ************* Value array ********** 50// (? bytes): node1's mapped_value 51// (? bytes): node2's mapped_value 52// ... 53// (? bytes): nodeN's mapped_value 54// 55// REQUIREMENT: Key type MUST be primitive type or pointers so that: 56// X = sizeof(typename Key); 57// 58// Note: since address offset is stored as uint32, user should keep in mind that 59// StaticMap only supports up to 4GB size of memory data. 60 61// Author: Siyang Xie (lambxsy@google.com) 62 63 64#ifndef PROCESSOR_STATIC_MAP_H__ 65#define PROCESSOR_STATIC_MAP_H__ 66 67#include "processor/static_map_iterator-inl.h" 68 69namespace google_breakpad { 70 71// Default functor to compare keys. 72template<typename Key> 73class DefaultCompare { 74 public: 75 int operator()(const Key &k1, const Key &k2) const { 76 if (k1 < k2) return -1; 77 if (k1 == k2) return 0; 78 return 1; 79 } 80}; 81 82template<typename Key, typename Value, typename Compare = DefaultCompare<Key> > 83class StaticMap { 84 public: 85 typedef StaticMapIterator<Key, Value, Compare> iterator; 86 typedef StaticMapIterator<Key, Value, Compare> const_iterator; 87 88 StaticMap() : raw_data_(0), 89 num_nodes_(0), 90 offsets_(0), 91 compare_() { } 92 93 explicit StaticMap(const char* raw_data); 94 95 inline bool empty() const { return num_nodes_ == 0; } 96 inline unsigned int size() const { return num_nodes_; } 97 98 // Return iterators. 99 inline iterator begin() const { return IteratorAtIndex(0); } 100 inline iterator last() const { return IteratorAtIndex(num_nodes_ - 1); } 101 inline iterator end() const { return IteratorAtIndex(num_nodes_); } 102 inline iterator IteratorAtIndex(int index) const { 103 return iterator(raw_data_, index); 104 } 105 106 // Lookup operations. 107 iterator find(const Key &k) const; 108 109 // lower_bound(k) searches in a sorted range for the first element that has a 110 // key not less than the argument k. 111 iterator lower_bound(const Key &k) const; 112 113 // upper_bound(k) searches in a sorted range for the first element that has a 114 // key greater than the argument k. 115 iterator upper_bound(const Key &k) const; 116 117 // Checks if the underlying memory data conforms to the predefined pattern: 118 // first check the number of nodes is non-negative, 119 // then check both offsets and keys are strictly increasing (sorted). 120 bool ValidateInMemoryStructure() const; 121 122 private: 123 const Key GetKeyAtIndex(int i) const; 124 125 // Start address of a raw memory chunk with serialized data. 126 const char* raw_data_; 127 128 // Number of nodes in the static map. 129 u_int32_t num_nodes_; 130 131 // Array of offset addresses for stored values. 132 // For example: 133 // address_of_i-th_node_value = raw_data_ + offsets_[i] 134 const u_int32_t* offsets_; 135 136 // keys_[i] = key of i_th node 137 const Key* keys_; 138 139 Compare compare_; 140}; 141 142} // namespace google_breakpad 143 144#endif // PROCESSOR_STATIC_MAP_H__