p_futimes: support using futimens when available

CMakeLists.txt

@@ -19,6 +19,7 @@ CMAKE_POLICY(SET CMP0015 NEW)
 SET(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_CURRENT_SOURCE_DIR}/cmake/Modules/")
 
 INCLUDE(CheckLibraryExists)
+INCLUDE(CheckFunctionExists)
 INCLUDE(AddCFlagIfSupported)
 INCLUDE(FindPkgConfig)
 
@@ -431,6 +432,11 @@ ELSE ()
 	ADD_C_FLAG_IF_SUPPORTED(-Wno-unused-const-variable)
 	ADD_C_FLAG_IF_SUPPORTED(-Wno-unused-function)
 
+	CHECK_FUNCTION_EXISTS(futimens HAVE_FUTIMENS)
+	IF (HAVE_FUTIMENS)
+		ADD_DEFINITIONS(-DHAVE_FUTIMENS)
+	ENDIF ()
+
 	IF (APPLE) # Apple deprecated OpenSSL
 		ADD_C_FLAG_IF_SUPPORTED(-Wno-deprecated-declarations)
 	ENDIF()

src/unix/posix.h

@@ -22,7 +22,6 @@ typedef int GIT_SOCKET;
 #define p_stat(p,b) stat(p, b)
 
 #define p_utimes(f, t) utimes(f, t)
-#define p_futimes(f, t) futimes(f, t)
 
 #define p_readlink(a, b, c) readlink(a, b, c)
 #define p_symlink(o,n) symlink(o, n)
@@ -53,4 +52,18 @@ extern char *p_realpath(const char *, char *);
 #define p_localtime_r(c, r) localtime_r(c, r)
 #define p_gmtime_r(c, r) gmtime_r(c, r)
 
+#ifdef HAVE_FUTIMENS
+GIT_INLINE(int) p_futimes(int f, const struct timeval t[2])
+{
+	struct timespec s[2];
+	s[0].tv_sec = t[0].tv_sec;
+	s[0].tv_nsec = t[0].tv_usec * 1000;
+	s[1].tv_sec = t[1].tv_sec;
+	s[1].tv_nsec = t[1].tv_usec * 1000;
+	return futimens(f, s);
+}
+#else
+# define p_futimes futimes
+#endif
+
 #endif