diff mbox

Remove __ASSUME_STATFS_F_FLAGS

Message ID alpine.DEB.2.20.1705101749270.8916@digraph.polyomino.org.uk
State New, archived
Headers show

Commit Message

Joseph Myers May 10, 2017, 5:50 p.m. UTC
Now that 3.2 is the minimum Linux kernel version for glibc, this patch
removes __ASSUME_STATFS_F_FLAGS and associated conditional code.

Tested for x86_64.

2017-05-10  Joseph Myers  <joseph@codesourcery.com>

	* sysdeps/unix/sysv/linux/kernel-features.h
	(__ASSUME_STATFS_F_FLAGS): Remove macro.
	* sysdeps/unix/sysv/linux/internal_statvfs.c
	[!__ASSUME_STATFS_F_FLAGS]: Remove conditional code.

Comments

Florian Weimer May 10, 2017, 6:06 p.m. UTC | #1
On 05/10/2017 07:50 PM, Joseph Myers wrote:
> -#ifndef __ASSUME_STATFS_F_FLAGS
> -  if ((fsbuf->f_flags & ST_VALID) == 0)
> -    /* Determining the flags is tricky.  We have to read /proc/mounts or
> -       the /etc/mtab file and search for the entry which matches the given
> -       file.  The way we can test for matching filesystem is using the
> -       device number.  */
> -    buf->f_flag = __statvfs_getflags (name, fsbuf->f_type, fd);
> -  else
> -#endif
> -    buf->f_flag = fsbuf->f_flags ^ ST_VALID;
> +  buf->f_flag = fsbuf->f_flags ^ ST_VALID;

Should we check the presence of the flag and return ENOSYS or abort if 
it missing?

Thanks,
Florian
Joseph Myers May 10, 2017, 8:15 p.m. UTC | #2
On Wed, 10 May 2017, Florian Weimer wrote:

> On 05/10/2017 07:50 PM, Joseph Myers wrote:
> > -#ifndef __ASSUME_STATFS_F_FLAGS
> > -  if ((fsbuf->f_flags & ST_VALID) == 0)
> > -    /* Determining the flags is tricky.  We have to read /proc/mounts or
> > -       the /etc/mtab file and search for the entry which matches the given
> > -       file.  The way we can test for matching filesystem is using the
> > -       device number.  */
> > -    buf->f_flag = __statvfs_getflags (name, fsbuf->f_type, fd);
> > -  else
> > -#endif
> > -    buf->f_flag = fsbuf->f_flags ^ ST_VALID;
> > +  buf->f_flag = fsbuf->f_flags ^ ST_VALID;
> 
> Should we check the presence of the flag and return ENOSYS or abort if it
> missing?

I don't know.  Not in this patch, which is meant only to clean up dead 
code without changing the generated code.
Florian Weimer May 12, 2017, 11:39 a.m. UTC | #3
On 05/10/2017 07:50 PM, Joseph Myers wrote:
> 2017-05-10  Joseph Myers<joseph@codesourcery.com>
> 
> 	* sysdeps/unix/sysv/linux/kernel-features.h
> 	(__ASSUME_STATFS_F_FLAGS): Remove macro.
> 	* sysdeps/unix/sysv/linux/internal_statvfs.c
> 	[!__ASSUME_STATFS_F_FLAGS]: Remove conditional code.

Patch looks good.

Thanks,
Florian
diff mbox

Patch

diff --git a/sysdeps/unix/sysv/linux/internal_statvfs.c b/sysdeps/unix/sysv/linux/internal_statvfs.c
index 5bc9735..9a17ca5 100644
--- a/sysdeps/unix/sysv/linux/internal_statvfs.c
+++ b/sysdeps/unix/sysv/linux/internal_statvfs.c
@@ -39,190 +39,6 @@ 
 # define STATFS statfs
 # define STATVFS statvfs
 # define INTERNAL_STATVFS __internal_statvfs
-
-
-# ifndef __ASSUME_STATFS_F_FLAGS
-int
-__statvfs_getflags (const char *name, int fstype, int fd)
-{
-  struct stat64 st;
-
-  if ((fd < 0 ? stat64 (name, &st) : fstat64 (fd, &st)) < 0)
-    return 0;
-
-  const char *fsname = NULL;
-  const char *fsname2 = NULL;
-  const char *fsname3 = NULL;
-
-  /* Map the filesystem type we got from the statfs call to a string.  */
-  switch (fstype)
-    {
-    case EXT2_SUPER_MAGIC:
-      fsname = "ext4";
-      fsname2 = "ext3";
-      fsname3 = "ext2";
-      break;
-    case DEVPTS_SUPER_MAGIC:
-      fsname= "devpts";
-      break;
-    case SHMFS_SUPER_MAGIC:
-      fsname = "tmpfs";
-      break;
-    case PROC_SUPER_MAGIC:
-      fsname = "proc";
-      break;
-    case USBDEVFS_SUPER_MAGIC:
-      fsname = "usbdevfs";
-      break;
-    case AUTOFS_SUPER_MAGIC:
-      fsname = "autofs";
-      break;
-    case NFS_SUPER_MAGIC:
-      fsname = "nfs";
-      break;
-    case SYSFS_MAGIC:
-      fsname = "sysfs";
-      break;
-    case REISERFS_SUPER_MAGIC:
-      fsname = "reiserfs";
-      break;
-    case XFS_SUPER_MAGIC:
-      fsname = "xfs";
-      break;
-    case JFS_SUPER_MAGIC:
-      fsname = "jfs";
-      break;
-    case HPFS_SUPER_MAGIC:
-      fsname = "hpfs";
-      break;
-    case DEVFS_SUPER_MAGIC:
-      fsname = "devfs";
-      break;
-    case ISOFS_SUPER_MAGIC:
-      fsname = "iso9660";
-      break;
-    case MSDOS_SUPER_MAGIC:
-      fsname = "msdos";
-      break;
-    case NTFS_SUPER_MAGIC:
-      fsname = "ntfs";
-      break;
-    case LOGFS_MAGIC_U32:
-      fsname = "logfs";
-      break;
-    case BTRFS_SUPER_MAGIC:
-      fsname = "btrfs";
-      break;
-    case CGROUP_SUPER_MAGIC:
-      fsname = "cgroup";
-      break;
-    case LUSTRE_SUPER_MAGIC:
-      fsname = "lustre";
-      break;
-    case F2FS_SUPER_MAGIC:
-      fsname = "f2fs";
-      break;
-    case EFIVARFS_MAGIC:
-      fsname = "efivarfs";
-      break;
-    }
-
-  FILE *mtab = __setmntent ("/proc/mounts", "r");
-  if (mtab == NULL)
-    mtab = __setmntent (_PATH_MOUNTED, "r");
-
-  int result = 0;
-  if (mtab != NULL)
-    {
-      bool success = false;
-      struct mntent mntbuf;
-      char tmpbuf[1024];
-
-      /* No locking needed.  */
-      (void) __fsetlocking (mtab, FSETLOCKING_BYCALLER);
-
-    again:
-      while (__getmntent_r (mtab, &mntbuf, tmpbuf, sizeof (tmpbuf)))
-	{
-	  /* In a first round we look for a given mount point, if
-	     we have a name.  */
-	  if (name != NULL && strcmp (name, mntbuf.mnt_dir) != 0)
-	    continue;
-	  /* We need to look at the entry only if the filesystem
-	     name matches.  If we have a filesystem name.  */
-	  else if (fsname != NULL
-		   && strcmp (fsname, mntbuf.mnt_type) != 0
-		   && (fsname2 == NULL
-		       || strcmp (fsname2, mntbuf.mnt_type) != 0)
-		   && (fsname3 == NULL
-		       || strcmp (fsname3, mntbuf.mnt_type) != 0))
-	    continue;
-
-	  /* Find out about the device the current entry is for.  */
-	  struct stat64 fsst;
-	  if (stat64 (mntbuf.mnt_dir, &fsst) >= 0
-	      && st.st_dev == fsst.st_dev)
-	    {
-	      /* Bingo, we found the entry for the device FD is on.
-		 Now interpret the option string.  */
-	      char *cp = mntbuf.mnt_opts;
-	      char *opt;
-
-	      while ((opt = __strsep (&cp, ",")) != NULL)
-		if (strcmp (opt, "ro") == 0)
-		  result |= ST_RDONLY;
-		else if (strcmp (opt, "nosuid") == 0)
-		  result |= ST_NOSUID;
-		else if (strcmp (opt, "noexec") == 0)
-		  result |= ST_NOEXEC;
-		else if (strcmp (opt, "nodev") == 0)
-		  result |= ST_NODEV;
-		else if (strcmp (opt, "sync") == 0)
-		  result |= ST_SYNCHRONOUS;
-		else if (strcmp (opt, "mand") == 0)
-		  result |= ST_MANDLOCK;
-		else if (strcmp (opt, "noatime") == 0)
-		  result |= ST_NOATIME;
-		else if (strcmp (opt, "nodiratime") == 0)
-		  result |= ST_NODIRATIME;
-		else if (strcmp (opt, "relatime") == 0)
-		  result |= ST_RELATIME;
-
-	      /* We can stop looking for more entries.  */
-	      success = true;
-	      break;
-	    }
-	}
-      /* Maybe the kernel names for the filesystems changed or the
-	 statvfs call got a name which was not the mount point.  Check
-	 again, this time without checking for name matches first.  */
-      if (! success && (name != NULL || fsname != NULL))
-	{
-	  if (name != NULL)
-	    /* Try without a mount point name.  */
-	    name = NULL;
-	  else
-	    {
-	      /* Try without a filesystem name.  */
-	      assert (fsname != NULL);
-	      fsname = fsname2 = fsname3 = NULL;
-	    }
-
-	  /* It is not strictly allowed to use rewind here.  But
-	     this code is part of the implementation so it is
-	     acceptable.  */
-	  rewind (mtab);
-
-	  goto again;
-	}
-
-      /* Close the file.  */
-      __endmntent (mtab);
-    }
-
-  return result;
-}
-# endif
 #else
 extern int __statvfs_getflags (const char *name, int fstype, int fd);
 #endif
@@ -267,14 +83,5 @@  INTERNAL_STATVFS (const char *name, struct STATVFS *buf,
   /* XXX I have no idea how to compute f_favail.  Any idea???  */
   buf->f_favail = buf->f_ffree;
 
-#ifndef __ASSUME_STATFS_F_FLAGS
-  if ((fsbuf->f_flags & ST_VALID) == 0)
-    /* Determining the flags is tricky.  We have to read /proc/mounts or
-       the /etc/mtab file and search for the entry which matches the given
-       file.  The way we can test for matching filesystem is using the
-       device number.  */
-    buf->f_flag = __statvfs_getflags (name, fsbuf->f_type, fd);
-  else
-#endif
-    buf->f_flag = fsbuf->f_flags ^ ST_VALID;
+  buf->f_flag = fsbuf->f_flags ^ ST_VALID;
 }
diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h
index 76053b5..8961e4d 100644
--- a/sysdeps/unix/sysv/linux/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/kernel-features.h
@@ -78,11 +78,6 @@ 
 #define __ASSUME_PREADV	1
 #define __ASSUME_PWRITEV	1
 
-/* statfs fills in f_flags since 2.6.36.  */
-#if __LINUX_KERNEL_VERSION >= 0x020624
-# define __ASSUME_STATFS_F_FLAGS	1
-#endif
-
 /* Support for sendmmsg functionality was added in 3.0.  */
 #define __ASSUME_SENDMMSG	1