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28
29// static_map-inl.h: StaticMap implementation.
30//
31// See static_map.h for documentation.
32//
33// Author: Siyang Xie (lambxsy@google.com)
34
35
36#ifndef PROCESSOR_STATIC_MAP_INL_H__
37#define PROCESSOR_STATIC_MAP_INL_H__
38
39#include "processor/static_map.h"
40#include "processor/static_map_iterator-inl.h"
41#include "processor/logging.h"
42
43namespace google_breakpad {
44
45template<typename Key, typename Value, typename Compare>
46StaticMap<Key, Value, Compare>::StaticMap(const char* raw_data)
47 : raw_data_(raw_data),
48 compare_() {
49 // First 4 Bytes store the number of nodes.
50 num_nodes_ = *(reinterpret_cast<const uint32_t*>(raw_data_));
51
52 offsets_ = reinterpret_cast<const uint32_t*>(
53 raw_data_ + sizeof(num_nodes_));
54
55 keys_ = reinterpret_cast<const Key*>(
56 raw_data_ + (1 + num_nodes_) * sizeof(uint32_t));
57}
58
59// find(), lower_bound() and upper_bound() implement binary search algorithm.
60template<typename Key, typename Value, typename Compare>
61StaticMapIterator<Key, Value, Compare>
62StaticMap<Key, Value, Compare>::find(const Key& key) const {
63 int begin = 0;
64 int end = num_nodes_;
65 int middle;
66 int compare_result;
67 while (begin < end) {
68 middle = begin + (end - begin) / 2;
69 compare_result = compare_(key, GetKeyAtIndex(middle));
70 if (compare_result == 0)
71 return IteratorAtIndex(middle);
72 if (compare_result < 0) {
73 end = middle;
74 } else {
75 begin = middle + 1;
76 }
77 }
78 return this->end();
79}
80
81template<typename Key, typename Value, typename Compare>
82StaticMapIterator<Key, Value, Compare>
83StaticMap<Key, Value, Compare>::lower_bound(const Key& key) const {
84 int begin = 0;
85 int end = num_nodes_;
86 int middle;
87 int comp_result;
88 while (begin < end) {
89 middle = begin + (end - begin) / 2;
90 comp_result = compare_(key, GetKeyAtIndex(middle));
91 if (comp_result == 0)
92 return IteratorAtIndex(middle);
93 if (comp_result < 0) {
94 end = middle;
95 } else {
96 begin = middle + 1;
97 }
98 }
99 return IteratorAtIndex(begin);
100}
101
102template<typename Key, typename Value, typename Compare>
103StaticMapIterator<Key, Value, Compare>
104StaticMap<Key, Value, Compare>::upper_bound(const Key& key) const {
105 int begin = 0;
106 int end = num_nodes_;
107 int middle;
108 int compare_result;
109 while (begin < end) {
110 middle = begin + (end - begin) / 2;
111 compare_result = compare_(key, GetKeyAtIndex(middle));
112 if (compare_result == 0)
113 return IteratorAtIndex(middle + 1);
114 if (compare_result < 0) {
115 end = middle;
116 } else {
117 begin = middle + 1;
118 }
119 }
120 return IteratorAtIndex(begin);
121}
122
123template<typename Key, typename Value, typename Compare>
124bool StaticMap<Key, Value, Compare>::ValidateInMemoryStructure() const {
125 // check the number of nodes is non-negative:
126 if (!raw_data_) return false;
127 int32_t num_nodes = *(reinterpret_cast<const int32_t*>(raw_data_));
128 if (num_nodes < 0) {
129 BPLOG(INFO) << "StaticMap check failed: negative number of nodes";
130 return false;
131 }
132
133 int node_index = 0;
134 if (num_nodes_) {
135 uint64_t first_offset = sizeof(int32_t) * (num_nodes_ + 1)
136 + sizeof(Key) * num_nodes_;
137 // Num_nodes_ is too large.
138 if (first_offset > 0xffffffffUL) {
139 BPLOG(INFO) << "StaticMap check failed: size exceeds limit";
140 return false;
141 }
142 if (offsets_[node_index] != static_cast<uint32_t>(first_offset)) {
143 BPLOG(INFO) << "StaticMap check failed: first node offset is incorrect";
144 return false;
145 }
146 }
147
148 for (node_index = 1; node_index < num_nodes_; ++node_index) {
149 // Check offsets[i] is strictly increasing:
150 if (offsets_[node_index] <= offsets_[node_index - 1]) {
151 BPLOG(INFO) << "StaticMap check failed: node offsets non-increasing";
152 return false;
153 }
154 // Check Key[i] is strictly increasing as no duplicate keys are allowed.
155 if (compare_(GetKeyAtIndex(node_index),
156 GetKeyAtIndex(node_index - 1)) <= 0) {
157 BPLOG(INFO) << "StaticMap check failed: node keys non-increasing";
158 return false;
159 }
160 }
161 return true;
162}
163
164template<typename Key, typename Value, typename Compare>
165const Key StaticMap<Key, Value, Compare>::GetKeyAtIndex(int index) const {
166 if (index < 0 || index >= num_nodes_) {
167 BPLOG(ERROR) << "Key index out of range error";
168 // Key type is required to be primitive type. Return 0 if index is invalid.
169 return 0;
170 }
171 return keys_[index];
172}
173
174} // namespace google_breakpad
175
176#endif // PROCESSOR_STATIC_MAP_INL_H__
177