Simplify CheckStrptime module

Author: petk

cmake/ext/standard/cmake/CheckStrptime.cmake

@@ -1,90 +1,52 @@
 #[=============================================================================[
-# CheckStrptime
+Check 'strptime()' and its declaration.
 
-Check `strptime()` and its declaration.
+Note: This module is obsolete. PHP 'strptime()' is deprecated as of PHP 8.1.0
+and strptime(), where available, simply needs the _GNU_SOURCE defined or
+compiler flag -std=gnuXX appended to be declared in time.h.
 
-Note: This module is obsolete. PHP `strptime()` is deprecated as of PHP 8.1.0.
+Result variables:
 
-## Cache variables
-
-* `HAVE_STRPTIME`
-
-  Whether `strptime()` is available.
-
-## Result variables
-
-* `HAVE_STRPTIME_DECL_FAILS`
-
-  Whether `strptime()` declaration fails.
-
-## Usage
-
-```cmake
-# CMakeLists.txt
-include(cmake/CheckStrptime.cmake)
-```
+* HAVE_STRPTIME
+* HAVE_STRPTIME_DECL_FAILS
 #]=============================================================================]
 
 include_guard(GLOBAL)
 
 include(CheckFunctionExists)
-include(CheckSourceCompiles)
 include(CheckSymbolExists)
 include(CMakePushCheckState)
 
 if(PHP_VERSION VERSION_GREATER_EQUAL 9.0)
   message(
     DEPRECATION
-    "PHP/CheckStrptime module is obsolete and should be removed. PHP "
-    "'strptime()' function is deprecated as of PHP 8.1.0."
+    "CheckStrptime module is obsolete and should be removed. PHP 'strptime()' "
+    "function is deprecated as of PHP 8.1.0."
   )
 endif()
 
+set(HAVE_STRPTIME FALSE)
+set(HAVE_STRPTIME_DECL_FAILS FALSE)
+
+if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
+  return()
+endif()
+
 cmake_push_check_state(RESET)
   set(CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE)
-  check_symbol_exists(strptime time.h HAVE_STRPTIME)
+  check_symbol_exists(strptime time.h PHP_EXT_STANDARD_HAS_STRPTIME)
 cmake_pop_check_state()
 
-if(HAVE_STRPTIME)
+if(PHP_EXT_STANDARD_HAS_STRPTIME)
+  set(HAVE_STRPTIME TRUE)
   set(HAVE_STRPTIME_DECL_FAILS TRUE)
   return()
 endif()
 
-# The rest of this module is obsolete because strptime(), where available,
-# simply needs the _GNU_SOURCE defined or compiler flag -std=gnuXX appended to
-# be declared in time.h. This part can be removed in favor of the above
-# check_symbol_exists().
-
 # Check if linker sees the function.
-if(NOT HAVE_STRPTIME)
-  unset(HAVE_STRPTIME CACHE)
-  check_function_exists(strptime HAVE_STRPTIME)
-endif()
+check_function_exists(strptime PHP_EXT_STANDARD_HAS_STRPTIME_FUNCTION)
 
-if(NOT HAVE_STRPTIME)
+if(PHP_EXT_STANDARD_HAS_STRPTIME_FUNCTION)
+  set(HAVE_STRPTIME TRUE)
   return()
 endif()
-
-message(CHECK_START "Checking whether strptime() is declared")
-
-cmake_push_check_state(RESET)
-  set(CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE)
-  set(CMAKE_REQUIRED_QUIET TRUE)
-
-  # Use invalid declaration to see if it fails to compile.
-  check_source_compiles(C [[
-    #include <time.h>
-    int main(void)
-    {
-      int strptime(const char *s, const char *format, struct tm *tm);
-      return 0;
-    }
-  ]] HAVE_STRPTIME_DECL)
-cmake_pop_check_state()
-
-if(NOT HAVE_STRPTIME_DECL)
-  message(CHECK_PASS "yes")
-  set(HAVE_STRPTIME_DECL_FAILS TRUE)
-else()
-  message(CHECK_FAIL "no")
-endif()