第07篇_Server 03｜多客户端接入，连接槽位和生命周期怎么设计

METHOD PRIVATE M_AcceptNewConnection
// === IMPLEMENTATION ===
// 工程说明：本段集中处理状态、边界或诊断，避免跨周期残留。
// 边界说明：执行前后保持输出和错误码可被在线诊断追踪。
bAcceptError := FALSE;
FOR uiSlotIndex := 1 TO GVL_Http.cnMaxClientSlots DO
    aTcpAccept[uiSlotIndex](
        xEnable := hServer <> 0,
        hServer := hServer
        );
    IF aTcpAccept[uiSlotIndex].xActive THEN
        IF (NOT aConnections[uiSlotIndex].bActive)
            OR (aConnections[uiSlotIndex].stConnection.hConnection <> aTcpAccept[uiSlotIndex].hConnection) THEN
            // 原因：接入阶段只绑定 NBS 句柄，读写统一留给 M_ServiceConnections；
            // 避免新连接在同一扫描周期被 TCP_Read 调用两次，导致大 body 半包场景被误判为接收错误。
            aConnections[uiSlotIndex].M_Attach(
                hConnection := aTcpAccept[uiSlotIndex].hConnection
                );
            stMetrics.udiAcceptedConnections := stMetrics.udiAcceptedConnections + 1;
        END_IF
    END_IF
    IF aTcpAccept[uiSlotIndex].xError THEN
        bAcceptError := TRUE;
        eTcpError := aTcpAccept[uiSlotIndex].eError;
        uiLastErrorSlot := uiSlotIndex;
    END_IF
END_FOR

IF bAcceptError THEN
    eLastNbsError := eTcpError;
    M_SetServerError(
        eError   := E_HttpError.iTcpServerFailed,
        sMessage := 'TCP accept failed'
        );
END_IF

// === METHOD M_ServiceConnections ===
/// =======================================================================
/// 名称      : M_ServiceConnections
/// 功能      : 周期服务所有 HTTP 连接槽位。

/// 说明      : 请求、响应、错误和清理均由连接 FB 输出聚合。
/// =======================================================================
{attribute 'hide_all_locals'}
METHOD PRIVATE M_ServiceConnections
// === IMPLEMENTATION ===
// 工程说明：本段集中处理状态、边界或诊断，避免跨周期残留。
// 边界说明：执行前后保持输出和错误码可被在线诊断追踪。
// 原因：每个连接槽都必须每周期服务，NBS 句柄状态变化可能发生在任意扫描周期。
// 诊断：最近请求槽、最近错误槽和连接快照用于外部探针复盘多连接真实通信路径。
uiActiveCount := 0;
FOR uiSlotIndex := 1 TO GVL_Http.cnMaxClientSlots DO
    aConnections[uiSlotIndex](
        bEnable             := aConnections[uiSlotIndex].bActive,
        xCloseConnection    := xCloseConnection,
        uiSlot              := uiSlotIndex,
        hConnectionIn       := aConnections[uiSlotIndex].stConnection.hConnection,
        bConnectionActiveIn := aConnections[uiSlotIndex].bActive,
        uiResponseStatusCode:= uiResponseStatusCode,
        sResponseBody       := sResponseBody,
        sResponseContentType:= sResponseContentType,
        sAdditionalHeader   := sAdditionalHeader,
        udiNowMs            := udiNowMs
        );

    IF aConnections[uiSlotIndex].bActive THEN
        uiActiveCount := uiActiveCount + 1;
    END_IF

    IF aConnections[uiSlotIndex].bRequestReady THEN
        uiLastRequestSlot := uiSlotIndex;
        sLastTarget := aConnections[uiSlotIndex].stRequest.sTarget;
        sLastBody := aConnections[uiSlotIndex].stRequest.sBody;
        sRequestTarget := aConnections[uiSlotIndex].stRequest.sTarget;
        sRequestBody := aConnections[uiSlotIndex].stRequest.sBody;
        sRxMessage := aConnections[uiSlotIndex].sRxMessage;
        stMetrics.udiRequestCount := stMetrics.udiRequestCount + 1;
    END_IF

    IF aConnections[uiSlotIndex].bResponseSent THEN
        sTxMessage := aConnections[uiSlotIndex].sTxMessage;