[PATCH 1/2] object-file: use futimes rather than utime

["Neeraj Singh via GitGitGadget" <gitgitgadget@gmail.com>]

From: Neeraj Singh <neerajsi@microsoft.com>

Refactor the loose object file creation code and use the futimes(2) API
rather than utime. This should be slightly faster given that we already
have an FD to work with.

Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
---
 compat/mingw.c | 42 +++++++++++++++++++++++++++++-------------
 compat/mingw.h |  2 ++
 object-file.c  | 17 ++++++++---------
 3 files changed, 39 insertions(+), 22 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 9e0cd1e097f..948f4c3428b 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -949,19 +949,40 @@ int mingw_fstat(int fd, struct stat *buf)
 	}
 }
 
-static inline void time_t_to_filetime(time_t t, FILETIME *ft)
+static inline void timeval_to_filetime(const struct timeval *t, FILETIME *ft)
 {
-	long long winTime = t * 10000000LL + 116444736000000000LL;
+	long long winTime = t->tv_sec * 10000000LL + t->tv_usec * 10 + 116444736000000000LL;
 	ft->dwLowDateTime = winTime;
 	ft->dwHighDateTime = winTime >> 32;
 }
 
-int mingw_utime (const char *file_name, const struct utimbuf *times)
+int mingw_futimes(int fd, const struct timeval times[2])
 {
 	FILETIME mft, aft;
+
+	if (times) {
+		timeval_to_filetime(&times[0], &aft);
+		timeval_to_filetime(&times[1], &mft);
+	} else {
+		GetSystemTimeAsFileTime(&mft);
+		aft = mft;
+	}
+
+	if (!SetFileTime((HANDLE)_get_osfhandle(fd), NULL, &aft, &mft)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	return 0;
+}
+
+int mingw_utime (const char *file_name, const struct utimbuf *times)
+{
 	int fh, rc;
 	DWORD attrs;
 	wchar_t wfilename[MAX_PATH];
+	struct timeval tvs[2];
+
 	if (xutftowcs_path(wfilename, file_name) < 0)
 		return -1;
 
@@ -979,17 +1000,12 @@ int mingw_utime (const char *file_name, const struct utimbuf *times)
 	}
 
 	if (times) {
-		time_t_to_filetime(times->modtime, &mft);
-		time_t_to_filetime(times->actime, &aft);
-	} else {
-		GetSystemTimeAsFileTime(&mft);
-		aft = mft;
+		memset(tvs, 0, sizeof(tvs));
+		tvs[0].tv_sec = times->actime;
+		tvs[1].tv_sec = times->modtime;
 	}
-	if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
-		errno = EINVAL;
-		rc = -1;
-	} else
-		rc = 0;
+
+	rc = mingw_futimes(fh, times ? tvs : NULL);
 	close(fh);
 
 revert_attrs:
diff --git a/compat/mingw.h b/compat/mingw.h
index c9a52ad64a6..1eb14edb2ed 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -398,6 +398,8 @@ int mingw_fstat(int fd, struct stat *buf);
 
 int mingw_utime(const char *file_name, const struct utimbuf *times);
 #define utime mingw_utime
+int mingw_futimes(int fd, const struct timeval times[2]);
+#define futimes mingw_futimes
 size_t mingw_strftime(char *s, size_t max,
 		   const char *format, const struct tm *tm);
 #define strftime mingw_strftime
diff --git a/object-file.c b/object-file.c
index a8be8994814..607e9e2f80b 100644
--- a/object-file.c
+++ b/object-file.c
@@ -1860,12 +1860,13 @@ int hash_object_file(const struct git_hash_algo *algo, const void *buf,
 }
 
 /* Finalize a file on disk, and close it. */
-static void close_loose_object(int fd)
+static int close_loose_object(int fd, const char *tmpfile, const char *filename)
 {
 	if (fsync_object_files)
 		fsync_or_die(fd, "loose object file");
 	if (close(fd) != 0)
 		die_errno(_("error when closing loose object file"));
+	return finalize_object_file(tmpfile, filename);
 }
 
 /* Size of directory component, including the ending '/' */
@@ -1973,17 +1974,15 @@ static int write_loose_object(const struct object_id *oid, char *hdr,
 		die(_("confused by unstable object source data for %s"),
 		    oid_to_hex(oid));
 
-	close_loose_object(fd);
-
 	if (mtime) {
-		struct utimbuf utb;
-		utb.actime = mtime;
-		utb.modtime = mtime;
-		if (utime(tmp_file.buf, &utb) < 0)
-			warning_errno(_("failed utime() on %s"), tmp_file.buf);
+		struct timeval tvs[2] = {0};
+		tvs[0].tv_sec = mtime;
+		tvs[1].tv_sec = mtime;
+		if (futimes(fd, tvs) < 0)
+			warning_errno(_("failed futimes() on %s"), tmp_file.buf);
 	}
 
-	return finalize_object_file(tmp_file.buf, filename.buf);
+	return close_loose_object(fd, tmp_file.buf, filename.buf);
 }
 
 static int freshen_loose_object(const struct object_id *oid)
-- 
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