Apologies if I have something signficant wrong; it's my first
nontrivial gnulib patch.
2007-03-24 James Youngman <[EMAIL PROTECTED]>
* lib/stat-time.h (get_stat_birthtime): New function for
retrieving st_birthtime as provided by UFS2 (hence *BSD).
* m4/stat-time.m4 (gl_STAT_BIRTHTIME): Probe for st_birthtime
and its variants.
* /modules/stat-time (configure.ac): call gl_STAT_BIRTHTIME.
Index: lib/stat-time.h
===================================================================
RCS file: /sources/gnulib/gnulib/lib/stat-time.h,v
retrieving revision 1.4
diff -u -p -r1.4 stat-time.h
--- lib/stat-time.h 23 Feb 2007 18:25:21 -0000 1.4
+++ lib/stat-time.h 24 Mar 2007 19:27:33 -0000
@@ -131,4 +131,66 @@ get_stat_mtime (struct stat const *st)
#endif
}
+/* Return *ST's birth time, if available, in *PTS. A nonzero value is
+ * returned if the stat structure appears to indicate that the
+ * timestamp is available.
+ *
+ * The return value of this function does not reliably indicate that the
+ * returned data is valid; see the comments within the body of the
+ * function for an explanation.
+ */
+#if defined(HAVE_STRUCT_STAT_ST_BIRTHTIME) ||
defined(HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC) ||
defined(HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC)
+static inline int
+get_stat_birthtime (struct stat const *st,
+ struct timespec *pts)
+{
+#ifdef STAT_TIMESPEC
+ *pts = STAT_TIMESPEC (st, st_birthtim);
+#else
+ struct timespec t;
+ pts->tv_sec = st->st_birthtime;
+ pts->tv_nsec = get_stat_birthtime_ns (st);
#endif
+
+#if 0 && defined(UTIME_OMIT)
+ /* This code is disabled because UTIME_OMIT is not currently specified
+ * to be set in any field by any stat() function. UTIME_OMIT is
+ * introduced in current (Sat Mar 24 15:30:59 2007) POSIX drafts for
+ * utimensat(). It is defined in <sys/time.h>.
+ */
+ if (UTIME_OMIT == pts->tv_nsec)
+ return 0;
+#endif
+
+ /* NetBSD sometimes signals the absence of knowledge of the file's
+ * birth time by using zero. Indicate we don't know. This is
+ * slightly problematic since (time_t)0 is otherwise a valid, albeit
+ * unlikely, timestamp. NetBSD sometimes returns 0 for unknown
+ * values (for example on ffs) and sometimes begative values for
+ * tv_nsec (for example on NFS).
+ *
+ * For some filesystems (e.g. msdos) NetBSD also appears to fail to
+ * update the st_birthtime member at all. Therefore callers are
+ * advised to initialise the tv_nsec number to a negative value
+ * before they call stat in order to detect this problem.
+ */
+ if (pts->tv_sec == (time_t)0)
+ return 0;
+ else
+ return (pts->tv_nsec >= 0) && (pts->tv_nsec <= 1000000000);
+}
+#else
+/* Birth time not supported. */
+static inline int
+get_stat_birthtime (struct stat const *st,
+ struct timespec *pts)
+{
+ pts->tv_sec = 0;
+ pts->tv_nsec = 0;
+ return 0;
+}
+#endif
+
+#endif
+
+
Index: m4/stat-time.m4
===================================================================
RCS file: /sources/gnulib/gnulib/m4/stat-time.m4,v
retrieving revision 1.4
diff -u -p -r1.4 stat-time.m4
--- m4/stat-time.m4 18 Jan 2007 08:33:35 -0000 1.4
+++ m4/stat-time.m4 24 Mar 2007 19:27:33 -0000
@@ -10,11 +10,13 @@
dnl From Paul Eggert.
# st_atim.tv_nsec - Linux, Solaris
-# st_atimespec.tv_nsec - FreeBSD, if ! defined _POSIX_SOURCE
-# st_atimensec - FreeBSD, if defined _POSIX_SOURCE
+# st_atimespec.tv_nsec - FreeBSD, NetBSD, if ! defined _POSIX_SOURCE
+# st_atimensec - FreeBSD, NetBSD, if defined _POSIX_SOURCE
# st_atim.st__tim.tv_nsec - UnixWare (at least 2.1.2 through 7.1)
# st_spare1 - Cygwin?
+# st_birthtimespec present on NetBSD (probably also FreBSD, OpenBSD)
+
AC_DEFUN([gl_STAT_TIME],
[
AC_REQUIRE([AC_C_INLINE])
@@ -61,3 +63,24 @@ AC_DEFUN([gl_STAT_TIME],
[#include <sys/types.h>
#include <sys/stat.h>])
])
+
+# Checks for st_birthtime, which is a feature from UFS2 (FreeBSD,
NetBSD, OpenBSD, etc.)
+# There was a time when this field was named st_createtime (21 June
2002 to 16 July 2002)
+# But that window is very small and applied only to development code,
so systems still
+# using that configuration are not a realistic development target.
+# See revisions 1.10 and 1.11 of FreeBSD's src/sys/ufs/ufs/dinode.h.
+#
+AC_DEFUN([gl_STAT_BIRTHTIME],
+[
+ AC_REQUIRE([AC_C_INLINE])
+ AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+ AC_CHECK_HEADERS_ONCE([sys/time.h])
+ AC_CHECK_MEMBERS([struct stat.st_birthtimespec.tv_sec,
+ struct stat.st_birthtimespec.tv_nsec], [],
+ dnl If not found, check for st_birthtime and st_birthtimensec
+ AC_CHECK_MEMBERS([struct stat.st_birthtime, struct
stat.st_birthtimensec], [], [],
+ [#include <sys/types.h>
+ #include <sys/stat.h>]),
+ [#include <sys/types.h>
+ #include <sys/stat.h>])
+])
Index: modules/stat-time
===================================================================
RCS file: /sources/gnulib/gnulib/modules/stat-time,v
retrieving revision 1.4
diff -u -p -r1.4 stat-time
--- modules/stat-time 12 Feb 2007 18:49:19 -0000 1.4
+++ modules/stat-time 24 Mar 2007 19:27:34 -0000
@@ -10,6 +10,7 @@ time
configure.ac:
gl_STAT_TIME
+gl_STAT_BIRTHTIME
Makefile.am:
