1 #pragma once 2 3 #include "callback.hpp" 4 #include "data_types.hpp" 5 6 #include <algorithm> 7 #include <functional> 8 9 namespace phosphor 10 { 11 namespace dbus 12 { 13 namespace monitoring 14 { 15 16 /** @class CountCondition 17 * @brief Count properties that satisfy a condition. 18 * 19 * When invoked, a count class instance performs its condition 20 * test in two passes. 21 * 22 * In pass one, apply a C++ relational operator to the value of 23 * each property in the index and a value provided by the 24 * configuration file. 25 * 26 * Count the number of properties that pass the test in pass 27 * one. In pass two, apply a second C++ relational operator 28 * to the number of properties that pass the test from pass one 29 * to a count provided by the configuration file. 30 * 31 * If the oneshot parameter is true, then this condition won't pass 32 * again until it fails at least once. 33 */ 34 template <typename T> 35 class CountCondition : public IndexedConditional 36 { 37 public: 38 CountCondition() = delete; 39 CountCondition(const CountCondition&) = default; 40 CountCondition(CountCondition&&) = default; 41 CountCondition& operator=(const CountCondition&) = default; 42 CountCondition& operator=(CountCondition&&) = default; 43 ~CountCondition() = default; 44 45 CountCondition(const PropertyIndex& conditionIndex, 46 const std::function<bool(size_t)>& _countOp, 47 const std::function<bool(T)>& _propertyOp, 48 bool oneshot = false) : 49 IndexedConditional(conditionIndex), 50 countOp(_countOp), propertyOp(_propertyOp), oneshot(oneshot) 51 { 52 } 53 54 bool operator()() override 55 { 56 // Count the number of properties in the index that 57 // pass the condition specified in the config file. 58 auto count = std::count_if( 59 index.cbegin(), index.cend(), 60 [this](const auto& item) 61 // *INDENT-OFF* 62 { 63 // Get the property value from storage[0], 64 // and save the op result in storage[1]. 65 const auto& storage = std::get<storageIndex>(item.second); 66 // Don't count properties that don't exist. 67 if (std::get<valueIndex>(storage.get()).empty()) 68 { 69 return false; 70 } 71 const auto& value = 72 any_ns::any_cast<T>(std::get<valueIndex>(storage.get())); 73 auto r = propertyOp(value); 74 75 std::get<resultIndex>(storage.get()) = r; 76 77 return r; 78 }); 79 // *INDENT-ON* 80 81 // Now apply the count condition to the count. 82 auto result = countOp(count); 83 84 // If this was a oneshot and the the condition has already 85 // passed, then don't let it pass again until the condition 86 // has gone back to false. 87 if (oneshot && result && lastResult) 88 { 89 return false; 90 } 91 92 lastResult = result; 93 return result; 94 } 95 96 private: 97 /** @brief The comparison to perform on the count. */ 98 std::function<bool(size_t)> countOp; 99 /** @brief The comparison to perform on each property. */ 100 std::function<bool(T)> propertyOp; 101 /** @brief If the condition can be allowed to pass again 102 on subsequent checks that are also true. */ 103 const bool oneshot; 104 /** @brief The result of the previous check. */ 105 bool lastResult = false; 106 }; 107 } // namespace monitoring 108 } // namespace dbus 109 } // namespace phosphor 110