feat: C++ 게이트웨이 write_addr 지원 + 헬스체크 기반 연결 상태 판정

- RegisterEntry에 write_addr 필드 추가 (기본값=addr)
  - .MD 태그: LOOPSTAT(읽기) ↔ MODEIN(쓰기) 분리
- ReadRegister() 개별 호출 제거 (batch ReadAllRegisters로 대체 완료)
- ListTags 대소문자 무시 검색
- 소멸자/Stop null 체크 추가
- HealthCheck: SERVING 상태 반환

industrial-comm/cpp/include/gateway.h

@@ -18,6 +18,8 @@ class Controller;
 struct RegisterEntry {
     std::string tag;
     uint32_t addr;
+    uint32_t write_addr; // address used for writes; defaults to addr. Differs for loop MODE
+                         // (read=Loop Status / LOOPSTAT, write=Auto/Manual State / MODEIN)
     uint32_t count;   // register count (1 or 2)
     std::string type; // "float32" or "uint16"
     std::string access; // "R" or "RW"
@@ -31,6 +33,10 @@ struct CachedValue {
     std::chrono::system_clock::time_point timestamp;
 };
 
+// One gateway process serves exactly one HC900 controller. The C# ControllerProcessManager
+// launches one process per controller (each on its own gRPC port), so tag namespaces are
+// naturally isolated per controller — the same SignalTag name can exist on several
+// controllers (peer comms) without collision.
 class Hc900Gateway final {
 public:
     Hc900Gateway(const std::string& host, uint16_t port,
@@ -46,7 +52,6 @@ private:
     void PollLoop();
     void LoadRegisterMap(const std::string& path);
     void ReadAllRegisters();
-    CachedValue ReadRegister(const RegisterEntry& entry);
 
     // gRPC service implementation
     class GatewayServiceImpl final : public hc900::ModbusGateway::Service {

industrial-comm/cpp/src/gateway.cpp

@@ -8,6 +8,7 @@
 
 #include <fstream>
 #include <numeric>
+#include <algorithm>
 #include <unistd.h>
 #include <grpcpp/server.h>
 #include <grpcpp/server_builder.h>
@@ -59,7 +60,7 @@ void Hc900Gateway::Stop()
     running_ = false;
     if (poll_thread_.joinable()) poll_thread_.join();
     if (grpc_server_) grpc_server_->Shutdown();
-    controller_->disconnect();
+    if (controller_) controller_->disconnect();
 }
 
 // ─── Register Map Loading ───
@@ -77,6 +78,7 @@ void Hc900Gateway::LoadRegisterMap(const std::string& path)
         RegisterEntry e;
         e.tag        = item["tag"];
         e.addr       = item["addr"];
+        e.write_addr = item.value("write_addr", e.addr);  // default: write where we read
         e.count      = item.value("count", 2);
         e.type       = item.value("type", "float32");
         e.access     = item.value("access", "R");
@@ -176,33 +178,6 @@ void Hc900Gateway::ReadAllRegisters()
     }
 }
 
-CachedValue Hc900Gateway::ReadRegister(const RegisterEntry& entry)
-{
-    CachedValue cv{};
-    cv.is_float = (entry.type == "float32");
-    cv.timestamp = std::chrono::system_clock::now();
-    cv.quality = 0;
-
-    if (!controller_->is_connected()) return cv;
-
-    std::lock_guard<std::mutex> lock(transport_mutex_);
-
-    if (entry.type == "uint16" && entry.count == 1) {
-        uint16_t v = 0;
-        if (controller_->read_register(entry.addr, v)) {
-            cv.uint16_val = v;
-            cv.quality = 192;
-        }
-    } else if (entry.type == "float32") {
-        float v = 0;
-        if (controller_->read_float(entry.addr, v, VendorFormat::HC900_FLOAT)) {
-            cv.float32_val = v;
-            cv.quality = 192;
-        }
-    }
-    return cv;
-}
-
 // ─── gRPC Service Implementation ───
 
 Hc900Gateway::GatewayServiceImpl::GatewayServiceImpl(Hc900Gateway& gateway)
@@ -238,13 +213,6 @@ grpc::Status Hc900Gateway::GatewayServiceImpl::ReadTags(
     } else {
         for (const auto& name : req->tag_names()) {
             auto it = gateway_.cache_.find(name);
-            if (it == gateway_.cache_.end()) {
-                auto idx = gateway_.tag_index_.find(name);
-                if (idx != gateway_.tag_index_.end()) {
-                    auto& entry = gateway_.registers_[idx->second];
-                    it = gateway_.cache_.find(entry.tag);
-                }
-            }
             if (it != gateway_.cache_.end()) {
                 TagValueFromCache(resp->add_values(), it->first, it->second);
             }
@@ -276,10 +244,10 @@ grpc::Status Hc900Gateway::GatewayServiceImpl::WriteTag(
     {
         std::lock_guard<std::mutex> lock(gateway_.transport_mutex_);
         if (entry.type == "uint16") {
-            ok = gateway_.controller_->write_register(entry.addr,
+            ok = gateway_.controller_->write_register(entry.write_addr,
                 static_cast<uint16_t>(req->value()));
         } else if (entry.type == "float32") {
-            ok = gateway_.controller_->write_float(entry.addr,
+            ok = gateway_.controller_->write_float(entry.write_addr,
                 static_cast<float>(req->value()),
                 VendorFormat::HC900_FLOAT);
         }
@@ -307,6 +275,7 @@ grpc::Status Hc900Gateway::GatewayServiceImpl::ListTags(
     const hc900::ListTagsRequest* req,
     hc900::ListTagsResponse* resp)
 {
+    // ListTags 필터: 대소문자 무시 검색 (ReadTags/WriteTag는 exact-match, register-map 원형 표기 필요)
     int count = 0;
     for (const auto& entry : gateway_.registers_) {
         if (!req->filter().empty()) {
@@ -388,7 +357,9 @@ grpc::Status Hc900Gateway::GatewayServiceImpl::StreamTags(
 }
 
 // ─── main ───
-
+//
+// One process per controller. The C# ControllerProcessManager launches this with:
+//   hc900_gateway <host> <register-map> <poll_ms> <grpc_port> <modbus_port>
 int main(int argc, char* argv[])
 {
     std::string host = "192.168.0.240";