From 7c0ffa1cb753f9b909dfb3bc7a5d5417b8de39c2 Mon Sep 17 00:00:00 2001
From: Johannes Sixt <johannes.sixt@telecom.at>
Date: Fri, 7 Sep 2007 13:05:00 +0200
Subject: [PATCH] Windows: Add a custom implementation for utime().

This is a necessary pendant to our lstat implementation: MSVCRT's
implementations of lstat and utime do some adjustments if daylight
saving time is in effect, but our lstat implementation doesn't do these
adjustments and report the correct UTC time.  With this implementation
we omit the adjustments in utime() as well and always write UTC.

Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
---
 compat/mingw.c | 27 +++++++++++++++++++++++++++
 compat/mingw.h |  3 +++
 2 files changed, 30 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index 6b742873da..2e47555443 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -155,6 +155,33 @@ int mingw_fstat(int fd, struct stat *buf)
 	return -1;
 }
 
+static inline void time_t_to_filetime(time_t t, FILETIME *ft)
+{
+	long long winTime = t * 10000000LL + 116444736000000000LL;
+	ft->dwLowDateTime = winTime;
+	ft->dwHighDateTime = winTime >> 32;
+}
+
+int mingw_utime (const char *file_name, const struct utimbuf *times)
+{
+	FILETIME mft, aft;
+	int fh, rc;
+
+	/* must have write permission */
+	if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0)
+		return -1;
+
+	time_t_to_filetime(times->modtime, &mft);
+	time_t_to_filetime(times->actime, &aft);
+	if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
+		errno = EINVAL;
+		rc = -1;
+	} else
+		rc = 0;
+	close(fh);
+	return rc;
+}
+
 unsigned int sleep (unsigned int seconds)
 {
 	Sleep(seconds*1000);
diff --git a/compat/mingw.h b/compat/mingw.h
index 69b1dde3ca..92e9273dd5 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -168,6 +168,9 @@ int mingw_fstat(int fd, struct stat *buf);
 #define lstat mingw_lstat
 #define stat(x,y) mingw_lstat(x,y)
 
+int mingw_utime(const char *file_name, const struct utimbuf *times);
+#define utime mingw_utime
+
 pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env);
 void mingw_execvp(const char *cmd, char *const *argv);
 #define execvp mingw_execvp