[cmake] Require CMake 3.17 or newer (#2556)

Remove code for older versions of CMake.
CMake 3.14 stopped running on Windows XP and Vista.

Fix detection of wcscmo, wcscpy, wcslen

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 55234b5ed6e3e540f0a604b1ccce98e89396955e..20e77453ca0052a6a85e9c41aeb5d05e759e3778 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,16 +1,6 @@
 #
-cmake_minimum_required(VERSION 3.5 FATAL_ERROR)
-if(APPLE AND CMAKE_VERSION VERSION_LESS "3.17.0")
-  message(WARNING "CMake>=3.17.0 required to make the generated shared library have the same Mach-O headers as autotools")
-endif()
+cmake_minimum_required(VERSION 3.17 FATAL_ERROR)
 
-if(POLICY CMP0074)
-  cmake_policy(SET CMP0074 NEW) #3.12.0 `find_package()`` uses ``<PackageName>_ROOT`` variables.
-endif()
-if(POLICY CMP0075)
-  cmake_policy(SET CMP0075 NEW) #3.12.0 `check_include_file()`` and friends use ``CMAKE_REQUIRED_LIBRARIES``.
-endif()
-#
 PROJECT(libarchive C)
 #
 SET(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/build/cmake")
@@ -293,18 +283,6 @@ IF(WIN32)
     SET(NTDDI_VERSION 0x06000100)
     SET(_WIN32_WINNT 0x0600)
     SET(WINVER 0x0600)
-  ELSEIF(WINDOWS_VERSION STREQUAL "VISTA")
-    SET(NTDDI_VERSION 0x06000000)
-    SET(_WIN32_WINNT 0x0600)
-    SET(WINVER 0x0600)
-  ELSEIF(WINDOWS_VERSION STREQUAL "WS03")
-    SET(NTDDI_VERSION 0x05020000)
-    SET(_WIN32_WINNT 0x0502)
-    SET(WINVER 0x0502)
-  ELSEIF(WINDOWS_VERSION STREQUAL "WINXP")
-    SET(NTDDI_VERSION 0x05010000)
-    SET(_WIN32_WINNT 0x0501)
-    SET(WINVER 0x0501)
   ELSE(WINDOWS_VERSION STREQUAL "WIN10")
     # Default to Windows Server 2003 API if we don't recognize the specifier
     SET(NTDDI_VERSION 0x05020000)
@@ -1546,9 +1524,9 @@ CHECK_FUNCTION_EXISTS_GLIBC(utimes HAVE_UTIMES)
 CHECK_FUNCTION_EXISTS_GLIBC(utimensat HAVE_UTIMENSAT)
 CHECK_FUNCTION_EXISTS_GLIBC(vfork HAVE_VFORK)
 CHECK_FUNCTION_EXISTS_GLIBC(wcrtomb HAVE_WCRTOMB)
-CHECK_FUNCTION_EXISTS_GLIBC(wcscmp HAVE_WCSCMP)
-CHECK_FUNCTION_EXISTS_GLIBC(wcscpy HAVE_WCSCPY)
-CHECK_FUNCTION_EXISTS_GLIBC(wcslen HAVE_WCSLEN)
+check_symbol_exists(wcscmp wchar.h HAVE_WCSCMP)
+check_symbol_exists(wcscpy wchar.h HAVE_WCSCPY)
+check_symbol_exists(wcslen wchar.h HAVE_WCSLEN)
 CHECK_FUNCTION_EXISTS_GLIBC(wctomb HAVE_WCTOMB)
 CHECK_FUNCTION_EXISTS_GLIBC(_fseeki64 HAVE__FSEEKI64)
 CHECK_FUNCTION_EXISTS_GLIBC(_get_timezone HAVE__GET_TIMEZONE)