Add ability to detect fsync availablilty in minipal.

src/native/minipal/configure.cmake

@@ -2,18 +2,16 @@ include(CheckFunctionExists)
 include(CheckIncludeFiles)
 include(CheckSymbolExists)
 
+check_include_files("windows.h" HAVE_WINDOWS_H)
+check_include_files("windows.h;bcrypt.h" HAVE_BCRYPT_H)
 check_include_files("sys/auxv.h;asm/hwcap.h" HAVE_AUXV_HWCAP_H)
+
 check_function_exists(sysctlbyname HAVE_SYSCTLBYNAME)
+check_function_exists(fsync HAVE_FSYNC)
 
 check_symbol_exists(arc4random_buf "stdlib.h" HAVE_ARC4RANDOM_BUF)
 check_symbol_exists(O_CLOEXEC fcntl.h HAVE_O_CLOEXEC)
-check_include_files("windows.h" HAVE_WINDOWS_H)
-check_include_files("windows.h;bcrypt.h" HAVE_BCRYPT_H)
-
-check_symbol_exists(
-    clock_gettime_nsec_np
-    time.h
-    HAVE_CLOCK_GETTIME_NSEC_NP)
+check_symbol_exists(clock_gettime_nsec_np time.h HAVE_CLOCK_GETTIME_NSEC_NP)
 
 if(CMAKE_C_BYTE_ORDER STREQUAL "BIG_ENDIAN")
     set(BIGENDIAN 1)

src/native/minipal/log.c

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+#include "minipalconfig.h"
 #include "log.h"
 #include <string.h>
 #include <limits.h>
@@ -247,7 +248,7 @@ static int sync_file(minipal_log_flags flags)
 
     return errno;
 }
-#elif defined(HAVE_FSYNC)
+#elif HAVE_FSYNC
 #include <unistd.h>
 static int sync_file(minipal_log_flags flags)
 {

src/native/minipal/minipalconfig.h.in

@@ -9,5 +9,6 @@
 #cmakedefine01 BIGENDIAN
 #cmakedefine01 HAVE_BCRYPT_H
 #cmakedefine01 HAVE_WINDOWS_H
+#cmakedefine01 HAVE_FSYNC
 
 #endif