Windows: make the CMake build work with MSYS2's native toolchain

CMakeLists.txt

@@ -18,12 +18,17 @@ endif()
 # Separate archive for MinGW so Linux host builds keep libsashidown.a
 if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
   set(SASHIDOWN_A "${SD_DIR}/libsashidown-mingw.a")
-  set(_MINGW_AR x86_64-w64-mingw32-ar)
+  # Use whatever archiver CMake found for the active toolchain. Hardcoding
+  # "x86_64-w64-mingw32-ar" only works on cross-build hosts, where binutils
+  # installs prefixed names; MSYS2's mingw-w64 toolchain ships plain ar.exe
+  # and ranlib.exe, so the hardcoded names are not found.
+  set(_MINGW_AR "${CMAKE_AR}")
+  set(_MINGW_RANLIB "${CMAKE_RANLIB}")
   add_custom_command(
     OUTPUT "${SASHIDOWN_A}"
     COMMAND ${CMAKE_MAKE_PROGRAM} -C "${SD_DIR}" clean
     COMMAND ${CMAKE_MAKE_PROGRAM} -C "${SD_DIR}" libsashidown.a
-            CC=${CMAKE_C_COMPILER} AR=${_MINGW_AR} RANLIB=x86_64-w64-mingw32-ranlib
+            CC=${CMAKE_C_COMPILER} AR=${_MINGW_AR} RANLIB=${_MINGW_RANLIB}
     COMMAND ${CMAKE_COMMAND} -E copy_if_different
             "${SD_DIR}/libsashidown.a" "${SASHIDOWN_A}"
     COMMAND ${CMAKE_MAKE_PROGRAM} -C "${SD_DIR}" clean
@@ -111,9 +116,11 @@ endif()
 if(CST_BUILD_TUI)
   if(WIN32)
     # Prefer PDCurses (pdcurses / curses). Users may set PDCurses_ROOT.
+    # PATH_SUFFIXES also covers the layout MSYS2's mingw-w64-pdcurses uses,
+    # which puts the headers under include/pdcurses/ rather than include/.
     find_path(PDCURSES_INCLUDE_DIR curses.h
       HINTS ENV PDCurses_ROOT "${PDCurses_ROOT}"
-      PATH_SUFFIXES include)
+      PATH_SUFFIXES include pdcurses include/pdcurses)
     find_library(PDCURSES_LIBRARY
       NAMES pdcurses pdcurses.dll curses
       HINTS ENV PDCurses_ROOT "${PDCurses_ROOT}"
@@ -121,7 +128,11 @@ if(CST_BUILD_TUI)
     if(PDCURSES_INCLUDE_DIR AND PDCURSES_LIBRARY)
       target_include_directories(cst-agent PRIVATE ${PDCURSES_INCLUDE_DIR})
       target_link_libraries(cst-agent PRIVATE ${PDCURSES_LIBRARY})
-      target_compile_definitions(cst-agent PRIVATE CST_USE_PDCURSES=1)
+      # PDCurses suffixes its exported symbols with an ABI tag (endwin_u64_4400
+      # etc.). MSYS2 builds the UTF-8 wide variant, so PDC_FORCE_UTF8 has to be
+      # defined or curses.h maps to the w64 names and the link fails.
+      target_compile_definitions(cst-agent PRIVATE
+        CST_USE_PDCURSES=1 PDC_FORCE_UTF8=1)
       message(STATUS "TUI: PDCurses (${PDCURSES_LIBRARY})")
     else()
       message(FATAL_ERROR "CST_BUILD_TUI=ON on Windows requires PDCurses (set PDCurses_ROOT)")
@@ -143,9 +154,9 @@ else()
 endif()
 
 if(CMAKE_SYSTEM_NAME STREQUAL "Windows" OR WIN32)
-  # curl Schannel + networking
+  # curl Schannel + networking; winmm is needed by PDCurses (PlaySoundW)
   target_link_libraries(cst-agent PRIVATE
-    ws2_32 crypt32 secur32 bcrypt advapi32)
+    ws2_32 crypt32 secur32 bcrypt advapi32 winmm)
 endif()
 
 # --- tests ---