重构代码的架构设计，增加测试单元，提高代码可靠性

tests/CMakeLists.txt

@@ -0,0 +1,108 @@
+# tests 子工程最低 CMake 版本要求（与主工程保持一致）
+cmake_minimum_required(VERSION 3.10)
+
+# 预留：测试通用源码列表（当前未直接使用，可用于后续统一链接）
+set(DTU_TEST_COMMON_SOURCES
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/ascii.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/key.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/menu.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/display.c"
+    "${CMAKE_SOURCE_DIR}/src/TCP/tcp.c"
+    "${CMAKE_SOURCE_DIR}/src/thread_utils.c"
+    "${CMAKE_SOURCE_DIR}/src/remoteDisplay.c"
+)
+
+# 封装测试目标创建逻辑：
+# - add_executable: 生成测试可执行文件
+# - target_include_directories: 注入项目头文件路径
+# - target_link_libraries: 按平台链接系统库
+# - add_test: 注册到 CTest，支持 ctest 统一执行
+function(add_dtu_test test_name)
+    add_executable(${test_name} ${ARGN})
+    # 测试目标可见的头文件目录
+    target_include_directories(${test_name} PRIVATE
+        "${CMAKE_SOURCE_DIR}/include"
+        "${CMAKE_SOURCE_DIR}/src"
+        "${CMAKE_SOURCE_DIR}/src/TCP"
+        "${CMAKE_SOURCE_DIR}/src/Drv"
+    )
+    # 平台差异：Windows 需要 ws2_32，非 Windows 使用 pthread
+    if(WIN32)
+        target_link_libraries(${test_name} PRIVATE ws2_32)
+    else()
+        target_link_libraries(${test_name} PRIVATE pthread)
+    endif()
+    # 将测试程序注册为 CTest 用例，名称与目标名一致
+    add_test(NAME ${test_name} COMMAND ${test_name})
+endfunction()
+
+# ------------------------------------------------------------
+# Smoke 测试：验证测试框架本身可用
+# ------------------------------------------------------------
+add_dtu_test(test_smoke tests_smoke.c)
+
+# ------------------------------------------------------------
+# P0：高价值纯逻辑测试
+# ------------------------------------------------------------
+add_dtu_test(
+    test_p0_remote_display
+    test_p0_remote_display.c
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd_draw.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd_text.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/ascii.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/key.c"
+    "${CMAKE_SOURCE_DIR}/src/TCP/tcp.c"
+    "${CMAKE_SOURCE_DIR}/src/thread_utils.c"
+)
+add_dtu_test(
+    test_p0_utf8_next
+    test_p0_utf8_next.c
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd_draw.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd_text.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/ascii.c"
+)
+add_dtu_test(
+    test_p0_utf8_hz12_get
+    test_p0_utf8_hz12_get.c
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/ascii.c"
+)
+
+# ------------------------------------------------------------
+# P1：业务核心计算/状态流转测试
+# ------------------------------------------------------------
+add_dtu_test(
+    test_p1_key
+    test_p1_key.c
+    "${CMAKE_SOURCE_DIR}/src/Drv/key.c"
+)
+add_dtu_test(
+    test_p1_lcd_basic
+    test_p1_lcd_basic.c
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd_draw.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd_text.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/ascii.c"
+)
+add_dtu_test(
+    test_p1_menu
+    test_p1_menu.c
+    "${CMAKE_SOURCE_DIR}/src/Drv/display.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd_draw.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/lcd_text.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/lcd/ascii.c"
+    "${CMAKE_SOURCE_DIR}/src/Drv/key.c"
+)
+
+# ------------------------------------------------------------
+# P2：集成测试（网络回环等）
+# ------------------------------------------------------------
+add_dtu_test(
+    test_p2_tcp_loopback
+    test_p2_tcp_loopback.c
+    "${CMAKE_SOURCE_DIR}/src/TCP/tcp.c"
+    "${CMAKE_SOURCE_DIR}/src/thread_utils.c"
+)