Port file-system-info to non-Microsoft

* admin/merge-gnulib (GNULIB_MODULES): Add fsusage.
* doc/emacs/files.texi (Directories): Remove documentation of
now-obsolete directory-free-space-program and
directory-free-space-args.
* etc/NEWS: Mention change.
* etc/PROBLEMS: Slow df is no longer a problem.
* lib/fsusage.c, lib/fsusage.h, m4/fsusage.m4:
New files, copied from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* lisp/dired.el (dired-free-space-program)
(dired-free-space-args): These aliases are now obsolete.
* lisp/files.el (directory-free-space-program)
(directory-free-space-args): Now obsolete.
(get-free-disk-space): Just call file-system-info instead
of the now-obsolete directory-free-space-program.
* nt/gnulib-cfg.mk (OMIT_GNULIB_MODULE_fsusage): New macro.
* src/fileio.c: Include fsusage.h.
(blocks_to_bytes, Ffile_system_info) [!DOS_NT]: New functions.
(syms_of_fileio) [!DOS_NT]: Defsubr file-system-info.

3 files changed, 340 insertions, 1 deletions

diff --git a/lib/fsusage.c b/lib/fsusage.c
new file mode 100644
index 00000000000..a0f763be05f
--- /dev/null
+++ b/lib/fsusage.c
@@ -0,0 +1,288 @@
+/* fsusage.c -- return space usage of mounted file systems
+
+   Copyright (C) 1991-1992, 1996, 1998-1999, 2002-2006, 2009-2017 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 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
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   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, see <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#include "fsusage.h"
+
+#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 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
+
+/* 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 int
+statvfs_works (void)
+{
+  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 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 (char const *file, char const *disk, struct fs_usage *fsp)
+{
+#ifdef STAT_STATVFS     /* POSIX, except pre-2.6.36 glibc/Linux */
+
+  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 (statvfs64 (file, &fsd) < 0)
+    return -1;
+
+  /* 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));
+
+#elif defined STAT_STATFS2_FS_DATA      /* Ultrix */
+
+  struct fs_data fsd;
+
+  if (statfs (file, &fsd) != 1)
+    return -1;
+
+  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);
+
+#elif defined STAT_STATFS3_OSF1         /* OSF/1 */
+
+  struct statfs fsd;
+
+  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
+     struct statfs are truncated to 2GB.  These conditions detect that
+     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 == 0x7fffffff / fsd.f_bsize && fsd.f_spare[0] > 0)
+    {
+      fsd.f_blocks = fsd.f_spare[0];
+      fsd.f_bfree = fsd.f_spare[1];
+      fsd.f_bavail = fsd.f_spare[2];
+    }
+# endif /* STATFS_TRUNCATES_BLOCK_COUNTS */
+
+#elif defined STAT_STATFS2_FSIZE        /* 4.4BSD and older NetBSD */
+
+  struct statfs fsd;
+
+  if (statfs (file, &fsd) < 0)
+    return -1;
+
+  fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
+
+#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 (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
+
+#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 = 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
+
+  (void) disk;  /* avoid argument-unused warning */
+  return 0;
+}
+
+#if defined _AIX && defined _I386
+/* AIX PS/2 does not supply statfs.  */
+
+int
+statfs (char *file, struct statfs *fsb)
+{
+  struct stat stats;
+  struct dustat fsd;
+
+  if (stat (file, &stats) != 0)
+    return -1;
+  if (dustat (stats.st_dev, 0, &fsd, sizeof (fsd)))
+    return -1;
+  fsb->f_type   = 0;
+  fsb->f_bsize  = fsd.du_bsize;
+  fsb->f_blocks = fsd.du_fsize - fsd.du_isize;
+  fsb->f_bfree  = fsd.du_tfree;
+  fsb->f_bavail = fsd.du_tfree;
+  fsb->f_files  = (fsd.du_isize - 2) * fsd.du_inopb;
+  fsb->f_ffree  = fsd.du_tinode;
+  fsb->f_fsid.val[0] = fsd.du_site;
+  fsb->f_fsid.val[1] = fsd.du_pckno;
+  return 0;
+}
+
+#endif /* _AIX && _I386 */
diff --git a/lib/fsusage.h b/lib/fsusage.h
new file mode 100644
index 00000000000..f78edc6a0cb
--- /dev/null
+++ b/lib/fsusage.h
@@ -0,0 +1,40 @@
+/* fsusage.h -- declarations for file system space usage info
+
+   Copyright (C) 1991-1992, 1997, 2003-2006, 2009-2017 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 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
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   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, see <https://www.gnu.org/licenses/>.  */
+
+/* Space usage statistics for a file system.  Blocks are 512-byte. */
+
+#if !defined FSUSAGE_H_
+# define FSUSAGE_H_
+
+# include <stdint.h>
+# include <stdbool.h>
+
+struct fs_usage
+{
+  uintmax_t fsu_blocksize;      /* Size of a block.  */
+  uintmax_t fsu_blocks;         /* Total blocks. */
+  uintmax_t fsu_bfree;          /* Free blocks available to superuser. */
+  uintmax_t fsu_bavail;         /* Free blocks available to non-superuser. */
+  bool fsu_bavail_top_bit_set;  /* 1 if fsu_bavail represents a value < 0.  */
+  uintmax_t fsu_files;          /* Total file nodes. */
+  uintmax_t fsu_ffree;          /* Free file nodes. */
+};
+
+int get_fs_usage (char const *file, char const *disk, struct fs_usage *fsp);
+
+#endif
diff --git a/lib/gnulib.mk.in b/lib/gnulib.mk.in
index 0f795b3d820..e9358a6855d 100644
--- a/lib/gnulib.mk.in
+++ b/lib/gnulib.mk.in
@@ -21,7 +21,7 @@
 # the same distribution terms as the rest of that program.
 #
 # Generated by gnulib-tool.
-# Reproduce by: gnulib-tool --import --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --avoid=close --avoid=dup --avoid=fchdir --avoid=fstat --avoid=malloc-posix --avoid=msvc-inval --avoid=msvc-nothrow --avoid=openat-die --avoid=opendir --avoid=raise --avoid=save-cwd --avoid=select --avoid=setenv --avoid=sigprocmask --avoid=stat --avoid=stdarg --avoid=stdbool --avoid=threadlib --avoid=tzset --avoid=unsetenv --avoid=utime --avoid=utime-h --gnu-make --makefile-name=gnulib.mk.in --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt binary-io byteswap c-ctype c-strcase careadlinkat close-stream count-leading-zeros count-one-bits count-trailing-zeros crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 d-type diffseq dtoastr dtotimespec dup2 environ execinfo explicit_bzero faccessat fcntl fcntl-h fdatasync fdopendir filemode filevercmp flexmember fstatat fsync getloadavg getopt-gnu gettime gettimeofday gitlog-to-changelog ignore-value intprops largefile lstat manywarnings memrchr minmax mkostemp mktime nstrftime pipe2 pselect pthread_sigmask putenv qcopy-acl readlink readlinkat sig2str socklen stat-time std-gnu11 stdalign stddef stdio stpcpy strtoimax symlink sys_stat sys_time tempname time time_r time_rz timegm timer-time timespec-add timespec-sub unlocked-io update-copyright utimens vla warnings
+# Reproduce by: gnulib-tool --import --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --avoid=close --avoid=dup --avoid=fchdir --avoid=fstat --avoid=malloc-posix --avoid=msvc-inval --avoid=msvc-nothrow --avoid=openat-die --avoid=opendir --avoid=raise --avoid=save-cwd --avoid=select --avoid=setenv --avoid=sigprocmask --avoid=stat --avoid=stdarg --avoid=stdbool --avoid=threadlib --avoid=tzset --avoid=unsetenv --avoid=utime --avoid=utime-h --gnu-make --makefile-name=gnulib.mk.in --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt binary-io byteswap c-ctype c-strcase careadlinkat close-stream count-leading-zeros count-one-bits count-trailing-zeros crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 d-type diffseq dtoastr dtotimespec dup2 environ execinfo explicit_bzero faccessat fcntl fcntl-h fdatasync fdopendir filemode filevercmp flexmember fstatat fsusage fsync getloadavg getopt-gnu gettime gettimeofday gitlog-to-changelog ignore-value intprops largefile lstat manywarnings memrchr minmax mkostemp mktime nstrftime pipe2 pselect pthread_sigmask putenv qcopy-acl readlink readlinkat sig2str socklen stat-time std-gnu11 stdalign stddef stdio stpcpy strtoimax symlink sys_stat sys_time tempname time time_r time_rz timegm timer-time timespec-add timespec-sub unlocked-io update-copyright utimens vla warnings
 
 
 MOSTLYCLEANFILES += core *.stackdump
@@ -1516,6 +1516,17 @@ EXTRA_libgnu_a_SOURCES += at-func.c fstatat.c
 endif
 ## end   gnulib module fstatat
 
+## begin gnulib module fsusage
+ifeq (,$(OMIT_GNULIB_MODULE_fsusage))
+
+
+EXTRA_DIST += fsusage.c fsusage.h
+
+EXTRA_libgnu_a_SOURCES += fsusage.c
+
+endif
+## end   gnulib module fsusage
+
 ## begin gnulib module fsync
 ifeq (,$(OMIT_GNULIB_MODULE_fsync))