eis/eqpalg/gb_item_memory.cc

#include <eqpalg/gb_item_memory.h>
#include <eqpalg/table_struct/t_rule_cfg.h>
#include <mix_cc/sql.h>
#include <mix_cc/sql/database/db2_t.h>
#include <array>
#include <atomic>
#include <chrono>
#include <mutex>
#include <shared_mutex>
#include <thread>
#include <tuple>
#include <vector>
#include "mix_cc/exception.h"

namespace {
// 双缓冲区结构
const size_t ArrayMax = 10000;
struct DoubleBufferArrays {
  std::vector<double> read_array;   // 读取用的数组
  std::vector<double> write_array;  // 写入用的数组
  void resize(size_t size) {
    read_array.resize(size);
    write_array.resize(size);
  }
  void swap_buffers() { std::swap(read_array, write_array); }

  std::vector<double>& get_write_array() { return write_array; }
};
bool data_updated = false;
DoubleBufferArrays buffer_arrays;
std::unordered_map<std::string, size_t> index_map;
std::shared_mutex buffer_mutex;  // 保护缓冲区交换的互斥锁
}

// 在类外定义并初始化静态成员变量（必须）
int GlobaltemSharedMemory::instanceCount = 0;

int GlobaltemSharedMemory::get_data_size() { return data_size_; }

int GlobaltemSharedMemory::get_instanceCount() { return instanceCount; }

GlobaltemSharedMemory::GlobaltemSharedMemory() {
  ++instanceCount;
  size_t index_value = 0;
  const auto prefix = string(CMemVar::Const()->UnitNo) + "_";
  for (int i = CMemVar::Const()->event_eis_start;
       i <= CMemVar::Const()->event_eis_end; i++) {
    binary_tele.ReBuild(i);
    const auto size = binary_tele.size();
    for (int j = 0; j < size; j++) {
      std::string name_without_plant_code = binary_tele[j].item;
      // 添加前缀
      auto item_name = prefix + name_without_plant_code;
      index_map[item_name] = index_value;
      index_value++;
    }
  }
  // 2. 初始化数组大小
  buffer_arrays.resize(index_value);
  logger_ = std::make_unique<LOG>("GlobaltemSharedMemory");
  logger_->Debug() << "GlobaltemSharedMemory::GlobaltemSharedMemory(),MaxIndex:"
                   << index_value << endl;
}

// 获取指定tag点数据 - 无锁读取
double GlobaltemSharedMemory::operator[](std::string tag_name) {
  // 直接读取前端缓冲区，无需加锁
  if (!data_updated) {
    return 0.0;
  }
  const auto& read_array = buffer_arrays.read_array;
  auto it = index_map.find(tag_name);
  if (it != index_map.end()) {
    size_t index_value = it->second;
    return index_value < data_size_ ? read_array[index_value] : 0;
  }
  return 0.0;
}

// 从共享内存缓存数据到写入缓冲区
int GlobaltemSharedMemory::cache_data() {
  try {
    auto& write_array = buffer_arrays.get_write_array();
    // 为共享内存中的数据添加机组号前缀
    size_t index_value = 0;
    for (int i = CMemVar::Const()->event_eis_start;
         i <= CMemVar::Const()->event_eis_end; i++) {
      if (true) {
        if (m_mapfix.find(i) == m_mapfix.end()) {
          m_mapfix.insert(
              make_pair(i, new CMemFix<PLC_DATA>(std::to_string(i))));
        }

        PLC_DATA* pdata = m_mapfix[i]->getCur();
        if (pdata == nullptr) {
          return -1 * i;
        }

        binary_tele.ReBuild(i, (char*)(pdata));
        const auto size = binary_tele.size();
        for (int j = 0; j < size; j++) {
          float value = binary_tele[j];
          write_array[index_value] = value;
          index_value++;
        }
      }
    }

    // 数据准备完成，交换缓冲区
    {
      std::unique_lock<std::shared_mutex> lock(buffer_mutex);
      buffer_arrays.swap_buffers();
      data_updated = true;
    }
    data_size_ = index_value;

  } catch (const std::exception& e) {
    std::throw_with_nested(
        mix_cc::Exception(-1, "shared mem load error", BOOST_CURRENT_LOCATION));
  }
  return 0;
}

//获取数据JSON表示 - 无锁读取
std::string GlobaltemSharedMemory::get_data_json() {
  mix_cc::json js1;
  try {
    const auto& read_array = buffer_arrays.read_array;
    if (!index_map.empty()) {
      for (auto iter : index_map) {
        size_t index_value = iter.second;
        js1[iter.first] =
            index_value < data_size_ ? read_array[index_value] : 0;
      }
      return js1.dump();
    } else {
      return "empty";
    }
  } catch (std::exception& e) {
    return "ERROR";
  }
}