X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Ffsusage.c;h=0657555f44d17805e7c90d8e4d6d5ae41296522a;hb=e7086a9a301ffcfef17edbcba9e7c0312c33f7a8;hp=e90abf94d836b6546311be637983d3aa9a8ccfcb;hpb=4b7e5ff7e5a45e9dc06927b2e356484ae8249be5;p=gnulib.git

diff --git a/lib/fsusage.c b/lib/fsusage.c
index e90abf94d..0657555f4 100644
--- a/lib/fsusage.c
+++ b/lib/fsusage.c
@@ -1,10 +1,12 @@
-/* fsusage.c -- return space usage of mounted filesystems
-   Copyright (C) 1991, 1992, 1996 Free Software Foundation, Inc.
+/* fsusage.c -- return space usage of mounted file systems
 
-   This program is free software; you can redistribute it and/or modify
+   Copyright (C) 1991-1992, 1996, 1998-1999, 2002-2006, 2009-2013 Free Software
+   Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -12,124 +14,171 @@
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software Foundation,
-   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
 
-#include <sys/types.h>
-#include <sys/stat.h>
 #include "fsusage.h"
 
-int statfs ();
+#include <limits.h>
+#include <sys/types.h>
 
+#if STAT_STATVFS || STAT_STATVFS64 /* POSIX 1003.1-2001 (and later) with XSI */
+# include <sys/statvfs.h>
+#else
+/* Don't include backward-compatibility files unless they're needed.
+   Eventually we'd like to remove all this cruft.  */
+# include <fcntl.h>
+# include <unistd.h>
+# include <sys/stat.h>
 #if HAVE_SYS_PARAM_H
 # include <sys/param.h>
 #endif
-
 #if HAVE_SYS_MOUNT_H
 # include <sys/mount.h>
 #endif
-
 #if HAVE_SYS_VFS_H
 # include <sys/vfs.h>
 #endif
-
-#if HAVE_SYS_FS_S5PARAM_H	/* Fujitsu UXP/V */
-# include <sys/fs/s5param.h>
-#endif
-
-#if defined (HAVE_SYS_FILSYS_H) && !defined (_CRAY)
-# include <sys/filsys.h>	/* SVR2 */
-#endif
-
-#if HAVE_FCNTL_H
-# include <fcntl.h>
-#endif
-
-#if HAVE_SYS_STATFS_H
-# include <sys/statfs.h>
-#endif
-
-#if HAVE_DUSTAT_H		/* AIX PS/2 */
-# include <sys/dustat.h>
-#endif
-
-#if HAVE_SYS_STATVFS_H		/* SVR4 */
-# include <sys/statvfs.h>
-int statvfs ();
+# if HAVE_SYS_FS_S5PARAM_H      /* Fujitsu UXP/V */
+#  include <sys/fs/s5param.h>
+# endif
+# if defined HAVE_SYS_FILSYS_H && !defined _CRAY
+#  include <sys/filsys.h>       /* SVR2 */
+# endif
+# if HAVE_SYS_STATFS_H
+#  include <sys/statfs.h>
+# endif
+# if HAVE_DUSTAT_H              /* AIX PS/2 */
+#  include <sys/dustat.h>
+# endif
+# include "full-read.h"
 #endif
 
-int safe_read ();
-
-/* Return the number of TOSIZE-byte blocks used by
-   BLOCKS FROMSIZE-byte blocks, rounding away from zero.
-   TOSIZE must be positive.  Return -1 if FROMSIZE is not positive.  */
+/* The results of open() in this file are not used with fchdir,
+   therefore save some unnecessary work in fchdir.c.  */
+#undef open
+#undef close
+
+/* Many space usage primitives use all 1 bits to denote a value that is
+   not applicable or unknown.  Propagate this information by returning
+   a uintmax_t value that is all 1 bits if X is all 1 bits, even if X
+   is unsigned and narrower than uintmax_t.  */
+#define PROPAGATE_ALL_ONES(x) \
+  ((sizeof (x) < sizeof (uintmax_t) \
+    && (~ (x) == (sizeof (x) < sizeof (int) \
+                  ? - (1 << (sizeof (x) * CHAR_BIT)) \
+                  : 0))) \
+   ? UINTMAX_MAX : (uintmax_t) (x))
+
+/* Extract the top bit of X as an uintmax_t value.  */
+#define EXTRACT_TOP_BIT(x) ((x) \
+                            & ((uintmax_t) 1 << (sizeof (x) * CHAR_BIT - 1)))
+
+/* If a value is negative, many space usage primitives store it into an
+   integer variable by assignment, even if the variable's type is unsigned.
+   So, if a space usage variable X's top bit is set, convert X to the
+   uintmax_t value V such that (- (uintmax_t) V) is the negative of
+   the original value.  If X's top bit is clear, just yield X.
+   Use PROPAGATE_TOP_BIT if the original value might be negative;
+   otherwise, use PROPAGATE_ALL_ONES.  */
+#define PROPAGATE_TOP_BIT(x) ((x) | ~ (EXTRACT_TOP_BIT (x) - 1))
+
+#ifdef STAT_STATVFS
+/* Return true if statvfs works.  This is false for statvfs on systems
+   with GNU libc on Linux kernels before 2.6.36, which stats all
+   preceding entries in /proc/mounts; that makes df hang if even one
+   of the corresponding file systems is hard-mounted but not available.  */
+# if ! (__linux__ && (__GLIBC__ || __UCLIBC__))
+/* The FRSIZE fallback is not required in this case.  */
+#  undef STAT_STATFS2_FRSIZE
+static int statvfs_works (void) { return 1; }
+# else
+#  include <string.h> /* for strverscmp */
+#  include <sys/utsname.h>
+#  include <sys/statfs.h>
+#  define STAT_STATFS2_BSIZE 1
 
-static long
-adjust_blocks (blocks, fromsize, tosize)
-     long blocks;
-     int fromsize, tosize;
+static int
+statvfs_works (void)
 {
-  if (tosize <= 0)
-    abort ();
-  if (fromsize <= 0)
-    return -1;
-
-  if (fromsize == tosize)	/* e.g., from 512 to 512 */
-    return blocks;
-  else if (fromsize > tosize)	/* e.g., from 2048 to 512 */
-    return blocks * (fromsize / tosize);
-  else				/* e.g., from 256 to 512 */
-    return (blocks + (blocks < 0 ? -1 : 1)) / (tosize / fromsize);
+  static int statvfs_works_cache = -1;
+  struct utsname name;
+  if (statvfs_works_cache < 0)
+    statvfs_works_cache = (uname (&name) == 0
+                           && 0 <= strverscmp (name.release, "2.6.36"));
+  return statvfs_works_cache;
 }
+# endif
+#endif
+
 
 /* Fill in the fields of FSP with information about space usage for
-   the filesystem on which PATH resides.
-   DISK is the device on which PATH is mounted, for space-getting
+   the file system on which FILE resides.
+   DISK is the device on which FILE is mounted, for space-getting
    methods that need to know it.
    Return 0 if successful, -1 if not.  When returning -1, ensure that
    ERRNO is either a system error value, or zero if DISK is NULL
    on a system that requires a non-NULL value.  */
 int
-get_fs_usage (path, disk, fsp)
-     const char *path;
-     const char *disk;
-     struct fs_usage *fsp;
+get_fs_usage (char const *file, char const *disk, struct fs_usage *fsp)
 {
-#ifdef STAT_STATFS3_OSF1
-# define CONVERT_BLOCKS(B) adjust_blocks ((B), fsd.f_fsize, 512)
+#ifdef STAT_STATVFS     /* POSIX, except pre-2.6.36 glibc/Linux */
 
-  struct statfs fsd;
+  if (statvfs_works ())
+    {
+      struct statvfs vfsd;
+
+      if (statvfs (file, &vfsd) < 0)
+        return -1;
+
+      /* f_frsize isn't guaranteed to be supported.  */
+      fsp->fsu_blocksize = (vfsd.f_frsize
+                            ? PROPAGATE_ALL_ONES (vfsd.f_frsize)
+                            : PROPAGATE_ALL_ONES (vfsd.f_bsize));
+
+      fsp->fsu_blocks = PROPAGATE_ALL_ONES (vfsd.f_blocks);
+      fsp->fsu_bfree = PROPAGATE_ALL_ONES (vfsd.f_bfree);
+      fsp->fsu_bavail = PROPAGATE_TOP_BIT (vfsd.f_bavail);
+      fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (vfsd.f_bavail) != 0;
+      fsp->fsu_files = PROPAGATE_ALL_ONES (vfsd.f_files);
+      fsp->fsu_ffree = PROPAGATE_ALL_ONES (vfsd.f_ffree);
+      return 0;
+    }
+
+#endif
+
+#if defined STAT_STATVFS64            /* AIX */
+
+  struct statvfs64 fsd;
 
-  if (statfs (path, &fsd, sizeof (struct statfs)) != 0)
+  if (statvfs64 (file, &fsd) < 0)
     return -1;
 
-#endif /* STAT_STATFS3_OSF1 */
+  /* f_frsize isn't guaranteed to be supported.  */
+  fsp->fsu_blocksize = (fsd.f_frsize
+                        ? PROPAGATE_ALL_ONES (fsd.f_frsize)
+                        : PROPAGATE_ALL_ONES (fsd.f_bsize));
 
-#ifdef STAT_STATFS2_FS_DATA	/* Ultrix */
-# define CONVERT_BLOCKS(B) adjust_blocks ((B), 1024, 512)
+#elif defined STAT_STATFS2_FS_DATA      /* Ultrix */
 
   struct fs_data fsd;
 
-  if (statfs (path, &fsd) != 1)
+  if (statfs (file, &fsd) != 1)
     return -1;
-  fsp->fsu_blocks = CONVERT_BLOCKS (fsd.fd_req.btot);
-  fsp->fsu_bfree = CONVERT_BLOCKS (fsd.fd_req.bfree);
-  fsp->fsu_bavail = CONVERT_BLOCKS (fsd.fd_req.bfreen);
-  fsp->fsu_files = fsd.fd_req.gtot;
-  fsp->fsu_ffree = fsd.fd_req.gfree;
 
-#endif /* STAT_STATFS2_FS_DATA */
+  fsp->fsu_blocksize = 1024;
+  fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.fd_req.btot);
+  fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.fd_req.bfree);
+  fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.fd_req.bfreen);
+  fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.fd_req.bfreen) != 0;
+  fsp->fsu_files = PROPAGATE_ALL_ONES (fsd.fd_req.gtot);
+  fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.fd_req.gfree);
 
-#ifdef STAT_READ_FILSYS		/* SVR2 */
+#elif defined STAT_READ_FILSYS          /* SVR2 */
 # ifndef SUPERBOFF
 #  define SUPERBOFF (SUPERB * 512)
 # endif
-# define CONVERT_BLOCKS(B) \
-    adjust_blocks ((B), (fsd.s_type == Fs2b ? 1024 : 512), 512)
 
   struct filsys fsd;
   int fd;
@@ -143,29 +192,53 @@ get_fs_usage (path, disk, fsp)
   fd = open (disk, O_RDONLY);
   if (fd < 0)
     return -1;
-  lseek (fd, (long) SUPERBOFF, 0);
-  if (safe_read (fd, (char *) &fsd, sizeof fsd) != sizeof fsd)
+  lseek (fd, (off_t) SUPERBOFF, 0);
+  if (full_read (fd, (char *) &fsd, sizeof fsd) != sizeof fsd)
     {
       close (fd);
       return -1;
     }
   close (fd);
-  fsp->fsu_blocks = CONVERT_BLOCKS (fsd.s_fsize);
-  fsp->fsu_bfree = CONVERT_BLOCKS (fsd.s_tfree);
-  fsp->fsu_bavail = CONVERT_BLOCKS (fsd.s_tfree);
-  fsp->fsu_files = (fsd.s_isize - 2) * INOPB * (fsd.s_type == Fs2b ? 2 : 1);
-  fsp->fsu_ffree = fsd.s_tinode;
 
-#endif /* STAT_READ_FILSYS */
+  fsp->fsu_blocksize = (fsd.s_type == Fs2b ? 1024 : 512);
+  fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.s_fsize);
+  fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.s_tfree);
+  fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.s_tfree);
+  fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.s_tfree) != 0;
+  fsp->fsu_files = (fsd.s_isize == -1
+                    ? UINTMAX_MAX
+                    : (fsd.s_isize - 2) * INOPB * (fsd.s_type == Fs2b ? 2 : 1));
+  fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.s_tinode);
 
-#ifdef STAT_STATFS2_BSIZE	/* 4.3BSD, SunOS 4, HP-UX, AIX */
-# define CONVERT_BLOCKS(B) adjust_blocks ((B), fsd.f_bsize, 512)
+#elif defined STAT_STATFS3_OSF1         /* OSF/1 */
 
   struct statfs fsd;
 
-  if (statfs (path, &fsd) < 0)
+  if (statfs (file, &fsd, sizeof (struct statfs)) != 0)
     return -1;
 
+  fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
+
+#elif defined STAT_STATFS2_FRSIZE        /* 2.6 < glibc/Linux < 2.6.36 */
+
+  struct statfs fsd;
+
+  if (statfs (file, &fsd) < 0)
+    return -1;
+
+  fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_frsize);
+
+#elif defined STAT_STATFS2_BSIZE        /* glibc/Linux < 2.6, 4.3BSD, SunOS 4, \
+                                           Mac OS X < 10.4, FreeBSD < 5.0, \
+                                           NetBSD < 3.0, OpenBSD < 4.4 */
+
+  struct statfs fsd;
+
+  if (statfs (file, &fsd) < 0)
+    return -1;
+
+  fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_bsize);
+
 # ifdef STATFS_TRUNCATES_BLOCK_COUNTS
 
   /* In SunOS 4.1.2, 4.1.3, and 4.1.3_U1, the block counts in the
@@ -173,7 +246,7 @@ get_fs_usage (path, disk, fsp)
      truncation, presumably without botching the 4.1.1 case, in which
      the values are not truncated.  The correct counts are stored in
      undocumented spare fields.  */
-  if (fsd.f_blocks == 0x1fffff && fsd.f_spare[0] > 0)
+  if (fsd.f_blocks == 0x7fffffff / fsd.f_bsize && fsd.f_spare[0] > 0)
     {
       fsd.f_blocks = fsd.f_spare[0];
       fsd.f_bfree = fsd.f_spare[1];
@@ -181,81 +254,65 @@ get_fs_usage (path, disk, fsp)
     }
 # endif /* STATFS_TRUNCATES_BLOCK_COUNTS */
 
-#endif /* STAT_STATFS2_BSIZE */
-
-#ifdef STAT_STATFS2_FSIZE	/* 4.4BSD */
-# define CONVERT_BLOCKS(B) adjust_blocks ((B), fsd.f_fsize, 512)
+#elif defined STAT_STATFS2_FSIZE        /* 4.4BSD and older NetBSD */
 
   struct statfs fsd;
 
-  if (statfs (path, &fsd) < 0)
+  if (statfs (file, &fsd) < 0)
     return -1;
 
-#endif /* STAT_STATFS2_FSIZE */
+  fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
 
-#ifdef STAT_STATFS4		/* SVR3, Dynix, Irix, AIX */
-# if _AIX || defined(_CRAY)
-#  define CONVERT_BLOCKS(B) adjust_blocks ((B), fsd.f_bsize, 512)
-#  ifdef _CRAY
-#   define f_bavail f_bfree
-#  endif
-# else
-#  define CONVERT_BLOCKS(B) (B)
-#  ifndef _SEQUENT_		/* _SEQUENT_ is DYNIX/ptx */
-#   ifndef DOLPHIN		/* DOLPHIN 3.8.alfa/7.18 has f_bavail */
-#    define f_bavail f_bfree
-#   endif
-#  endif
+#elif defined STAT_STATFS4              /* SVR3, Dynix, old Irix, old AIX, \
+                                           Dolphin */
+
+# if !_AIX && !defined _SEQUENT_ && !defined DOLPHIN
+#  define f_bavail f_bfree
 # endif
 
   struct statfs fsd;
 
-  if (statfs (path, &fsd, sizeof fsd, 0) < 0)
+  if (statfs (file, &fsd, sizeof fsd, 0) < 0)
     return -1;
+
   /* Empirically, the block counts on most SVR3 and SVR3-derived
      systems seem to always be in terms of 512-byte blocks,
      no matter what value f_bsize has.  */
+# if _AIX || defined _CRAY
+   fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_bsize);
+# else
+   fsp->fsu_blocksize = 512;
+# endif
 
-#endif /* STAT_STATFS4 */
-
-#ifdef STAT_STATVFS		/* SVR4 */
-# define CONVERT_BLOCKS(B) \
-    adjust_blocks ((B), fsd.f_frsize ? fsd.f_frsize : fsd.f_bsize, 512)
-
-  struct statvfs fsd;
-
-  if (statvfs (path, &fsd) < 0)
-    return -1;
-  /* f_frsize isn't guaranteed to be supported.  */
-
-#endif /* STAT_STATVFS */
+#endif
 
-#if !defined(STAT_STATFS2_FS_DATA) && !defined(STAT_READ_FILSYS)
-				/* !Ultrix && !SVR2 */
+#if (defined STAT_STATVFS64 || defined STAT_STATFS3_OSF1                \
+     || defined STAT_STATFS2_FRSIZE || defined STAT_STATFS2_BSIZE       \
+     || defined STAT_STATFS2_FSIZE || defined STAT_STATFS4)
 
-  fsp->fsu_blocks = CONVERT_BLOCKS (fsd.f_blocks);
-  fsp->fsu_bfree = CONVERT_BLOCKS (fsd.f_bfree);
-  fsp->fsu_bavail = CONVERT_BLOCKS (fsd.f_bavail);
-  fsp->fsu_files = fsd.f_files;
-  fsp->fsu_ffree = fsd.f_ffree;
+  fsp->fsu_blocks = PROPAGATE_ALL_ONES (fsd.f_blocks);
+  fsp->fsu_bfree = PROPAGATE_ALL_ONES (fsd.f_bfree);
+  fsp->fsu_bavail = PROPAGATE_TOP_BIT (fsd.f_bavail);
+  fsp->fsu_bavail_top_bit_set = EXTRACT_TOP_BIT (fsd.f_bavail) != 0;
+  fsp->fsu_files = PROPAGATE_ALL_ONES (fsd.f_files);
+  fsp->fsu_ffree = PROPAGATE_ALL_ONES (fsd.f_ffree);
 
-#endif /* not STAT_STATFS2_FS_DATA && not STAT_READ_FILSYS */
+#endif
 
+  (void) disk;  /* avoid argument-unused warning */
   return 0;
 }
 
-#if defined(_AIX) && defined(_I386)
+#if defined _AIX && defined _I386
 /* AIX PS/2 does not supply statfs.  */
 
 int
-statfs (path, fsb)
-     char *path;
-     struct statfs *fsb;
+statfs (char *file, struct statfs *fsb)
 {
   struct stat stats;
   struct dustat fsd;
 
-  if (stat (path, &stats))
+  if (stat (file, &stats) != 0)
     return -1;
   if (dustat (stats.st_dev, 0, &fsd, sizeof (fsd)))
     return -1;