Re: [PATCH] hurd: Define and pass UTIME_NOW and UTIME_OMIT to new file_utimens RPC

[Flavio Cruz <flaviocruz at gmail dot com>]

On Mon, Nov 09, 2015 at 10:56:19AM -0800, Roland McGrath wrote:
> Don't repeat all that code.  Make a shared helper function _hurd_futimens
> or suchlike.

Done. I've added a new file utime-helper.c that is included by the other files and refactors common code into 3 functions.

> 
> > 2015-09-20  Fláo Cruz  <flaviocruz@gmail.com>
> > 
> > 	Define and pass UTIME_NOW and UTIME_OMIT to new file_utimens RPC.
> > 
> > 	* sysdeps/mach/hurd/bits/stat.h (UTIME_NOW, UTIME_OMIT): New macros.
> 
> No blank line there.  A ChangeLog paragraph (sequence with no blank lines)
> covers a single logical change.  If you want to put a descriptive sentence
> (not associated with a particular file) at the top of the change, then it
> is the first line of the paragraph.
> 
> > --- a/sysdeps/mach/hurd/bits/stat.h
> > +++ b/sysdeps/mach/hurd/bits/stat.h
> > @@ -246,6 +246,10 @@ struct stat64
> >  # define SF_NOUNLINK	0x00100000	/* file may not be removed or renamed */
> >  # define SF_SNAPSHOT	0x00200000	/* snapshot inode */
> >  
> > +/* Time flags for futimens. */
> > +#define UTIME_NOW   -1  /* corresponds to the current time */
> > +#define UTIME_OMIT  -2  /* target time is omitted */
> 
> These should be under #ifdef __USE_ATFILE as they are in other bits/stat.h
> files.  These are not "flags".  They are special values for the tv_nsec
> field.  Two spaces after a period.
> 

Done. Please take another look.

Thanks!

diff --git a/sysdeps/mach/hurd/bits/stat.h b/sysdeps/mach/hurd/bits/stat.h
index f60a58a..7f7a124 100644
--- a/sysdeps/mach/hurd/bits/stat.h
+++ b/sysdeps/mach/hurd/bits/stat.h
@@ -246,6 +246,11 @@ struct stat64
 # define SF_NOUNLINK   0x00100000  /* file may not be removed or renamed */
 # define SF_SNAPSHOT   0x00200000  /* snapshot inode */
 
+#ifdef __USE_ATFILE
+# define UTIME_NOW  -1 /* corresponds to the current time */
+# define UTIME_OMIT -2 /* target time is omitted */
+#endif
+
 __BEGIN_DECLS
 
 /* Set file flags for FILE to FLAGS.  */
diff --git a/sysdeps/mach/hurd/futimens.c b/sysdeps/mach/hurd/futimens.c
index 4f82f1e..3159cb0 100644
--- a/sysdeps/mach/hurd/futimens.c
+++ b/sysdeps/mach/hurd/futimens.c
@@ -27,24 +27,51 @@
 int
 __futimens (int fd, const struct timespec tsp[2])
 {
-  time_value_t atime, mtime;
+  struct timespec atime, mtime;
   error_t err;
 
   if (tsp == NULL)
     {
-      /* Setting the number of microseconds to `-1' tells the
+      /* Setting the number of nanoseconds to UTIME_NOW tells the
          underlying filesystems to use the current time.  */
-      atime.microseconds = mtime.microseconds = -1;
+      atime.tv_sec = 0;
+      atime.tv_nsec = UTIME_NOW;
+      mtime.tv_sec = 0;
+      mtime.tv_nsec = UTIME_NOW;
     }
   else
     {
-      atime.seconds = tsp[0].tv_sec;
-      atime.microseconds = tsp[0].tv_nsec / 1000;
-      mtime.seconds = tsp[1].tv_sec;
-      mtime.microseconds = tsp[1].tv_nsec / 1000;
+      atime = tsp[0];
+      mtime = tsp[1];
     }
 
-  err = HURD_DPORT_USE (fd, __file_utimes (port, atime, mtime));
+  err = HURD_DPORT_USE (fd, __file_utimens (port, atime, mtime));
+
+  if (err == MIG_BAD_ID || err == EOPNOTSUPP)
+    {
+      time_value_t atim, mtim;
+
+      if (tsp == NULL)
+        /* Setting the number of microseconds to `-1' tells the
+           underlying filesystems to use the current time.  */
+        atim.microseconds = mtim.microseconds = -1;
+      else if (tsp[0].tv_nsec == UTIME_OMIT || tsp[1].tv_nsec == UTIME_OMIT)
+        return EOPNOTSUPP;
+      else
+        {
+          if (tsp[0].tv_nsec == UTIME_NOW)
+            atim.microseconds = -1;
+          else
+            TIMESPEC_TO_TIME_VALUE (&atim, &(tsp[0]));
+          if (tsp[1].tv_nsec == UTIME_NOW)
+            mtim.microseconds = -1;
+          else
+            TIMESPEC_TO_TIME_VALUE (&mtim, &(tsp[1]));
+        }
+
+      err = HURD_DPORT_USE (fd, __file_utimes (port, atim, mtim));
+  }
+
   return err ? __hurd_dfail (fd, err) : 0;
 }
 weak_alias (__futimens, futimens)
diff --git a/sysdeps/mach/hurd/futimes.c b/sysdeps/mach/hurd/futimes.c
index c325d44..5963151 100644
--- a/sysdeps/mach/hurd/futimes.c
+++ b/sysdeps/mach/hurd/futimes.c
@@ -22,29 +22,29 @@
 #include <hurd.h>
 #include <hurd/fd.h>
 
+#include "utime-helper.c"
+
 /* Change the access time of FD to TVP[0] and
    the modification time of FD to TVP[1].  */
 int
 __futimes (int fd, const struct timeval tvp[2])
 {
-  union tv
-  {
-    struct timeval tv;
-    time_value_t tvt;
-  };
-  const union tv *u = (const union tv *) tvp;
-  union tv nulltv[2];
+  struct timespec atime, mtime;
   error_t err;
 
-  if (tvp == NULL)
+  utime_ts_from_tval (tvp, &atime, &mtime);
+
+  err = HURD_DPORT_USE (fd, __file_utimens (port, atime, mtime));
+
+  if (err == EMIG_BAD_ID || err == EOPNOTSUPP)
     {
-      /* Setting the number of microseconds to `-1' tells the
-         underlying filesystems to use the current time.  */
-      nulltv[0].tvt.microseconds = nulltv[1].tvt.microseconds = -1;
-      u = nulltv;
+      time_value_t atim, mtim;
+
+      utime_tvalue_from_tval (tvp, &atim, &mtim);
+
+      err = HURD_DPORT_USE (fd, __file_utimes (port, atim, mtim));
     }
 
-  err = HURD_DPORT_USE (fd, __file_utimes (port, u[0].tvt, u[1].tvt));
   return err ? __hurd_dfail (fd, err) : 0;
 }
 weak_alias (__futimes, futimes)
diff --git a/sysdeps/mach/hurd/lutimes.c b/sysdeps/mach/hurd/lutimes.c
index 260842d..bddc54f 100644
--- a/sysdeps/mach/hurd/lutimes.c
+++ b/sysdeps/mach/hurd/lutimes.c
@@ -22,33 +22,22 @@
 #include <hurd.h>
 #include <fcntl.h>
 
+#include "utime-helper.c"
+
 /* Change the access time of FILE to TVP[0] and
    the modification time of FILE to TVP[1].  */
 int
 __lutimes (const char *file, const struct timeval tvp[2])
 {
-  union tv
-  {
-    struct timeval tv;
-    time_value_t tvt;
-  };
-  const union tv *u = (const union tv *) tvp;
-  union tv nulltv[2];
   error_t err;
   file_t port;
 
-  if (tvp == NULL)
-    {
-      /* Setting the number of microseconds to `-1' tells the
-         underlying filesystems to use the current time.  */
-      nulltv[0].tvt.microseconds = nulltv[1].tvt.microseconds = -1;
-      u = nulltv;
-    }
-
   port = __file_name_lookup (file, O_NOLINK, 0);
   if (port == MACH_PORT_NULL)
     return -1;
-  err = __file_utimes (port, u[0].tvt, u[1].tvt);
+
+  err = hurd_futimens (port, tvp);
+
   __mach_port_deallocate (__mach_task_self (), port);
   if (err)
     return __hurd_fail (err);
diff --git a/sysdeps/mach/hurd/utime-helper.c b/sysdeps/mach/hurd/utime-helper.c
index e69de29..93a556a 100644
--- a/sysdeps/mach/hurd/utime-helper.c
+++ b/sysdeps/mach/hurd/utime-helper.c
@@ -0,0 +1,84 @@
+/* Threshold at which to diagnose ELOOP.  Hurd version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <hurd/hurd_types.h>
+#include <stddef.h>
+#include <sys/time.h>
+
+/* Initializes atime/mtime timespec structures from an array of timeval.  */
+static inline void
+utime_ts_from_tval (const struct timeval tvp[2],
+      struct timespec *atime, struct timespec *mtime)
+{
+  if (tvp == NULL)
+    {
+      /* Setting the number of nanoseconds to UTIME_NOW tells the
+         underlying filesystems to use the current time.  */
+      atime->tv_sec = 0;
+      atime->tv_nsec = UTIME_NOW;
+      mtime->tv_sec = 0;
+      mtime->tv_nsec = UTIME_NOW;
+    }
+  else
+    {
+      TIMEVAL_TO_TIMESPEC (&tvp[0], atime);
+      TIMEVAL_TO_TIMESPEC (&tvp[1], mtime);
+    }
+}
+
+/* Initializes atime/mtime time_value_t structures from an array of timeval.  */
+static inline void
+utime_tvalue_from_tval (const struct timeval tvp[2],
+      time_value_t *atime, time_value_t *mtime)
+{
+  if (tvp == NULL)
+    /* Setting the number of microseconds to `-1' tells the
+       underlying filesystems to use the current time.  */
+    atime->microseconds = mtime->microseconds = -1;
+  else
+    {
+      atime->seconds = tvp[0].tv_sec;
+      atime->microseconds = tvp[0].tv_usec;
+      mtime->seconds = tvp[1].tv_sec;
+      mtime->microseconds = tvp[1].tv_usec;
+    }
+}
+
+/* Changes the access time of the file behind PORT using a timeval array.  */
+static inline error_t
+hurd_futimens (const file_t port, const struct timeval tvp[2])
+{
+  error_t err;
+  struct timespec atime, mtime;
+
+  utime_ts_from_tval (tvp, &atime, &mtime);
+
+  err = __file_utimens (port, atime, mtime);
+
+  if (err == MIG_BAD_ID || err == EOPNOTSUPP)
+    {
+      time_value_t atim, mtim;
+
+      utime_tvalue_from_tval (tvp, &atim, &mtim);
+
+      err = __file_utimes (port, atim, mtim);
+    }
+
+  return err;
+}
diff --git a/sysdeps/mach/hurd/utimes.c b/sysdeps/mach/hurd/utimes.c
index 6739b79..ae1921e 100644
--- a/sysdeps/mach/hurd/utimes.c
+++ b/sysdeps/mach/hurd/utimes.c
@@ -20,6 +20,8 @@
 #include <stddef.h>
 #include <hurd.h>
 
+#include "utime-helper.c"
+
 /* Change the access time of FILE to TVP[0] and
    the modification time of FILE to TVP[1].  */
 int
@@ -27,28 +29,15 @@ __utimes (file, tvp)
      const char *file;
      const struct timeval tvp[2];
 {
-  union tv
-  {
-    struct timeval tv;
-    time_value_t tvt;
-  };
-  const union tv *u = (const union tv *) tvp;
-  union tv nulltv[2];
   error_t err;
   file_t port;
 
-  if (tvp == NULL)
-    {
-      /* Setting the number of microseconds to `-1' tells the
-         underlying filesystems to use the current time.  */
-      nulltv[0].tvt.microseconds = nulltv[1].tvt.microseconds = -1;
-      u = nulltv;
-    }
-
   port = __file_name_lookup (file, 0, 0);
   if (port == MACH_PORT_NULL)
     return -1;
-  err = __file_utimes (port, u[0].tvt, u[1].tvt);
+
+  err = hurd_futimens (port, tvp);
+
   __mach_port_deallocate (__mach_task_self (), port);
   if (err)
     return __hurd_fail (err);