Portability problems fixed by Gnulib:
@itemize
@item
-When the argument ends in a slash, some platforms don't dereference the
-argument.
+For symlinks, when the argument ends in a slash, some platforms don't
+dereference the argument:
+Solaris 9.
+@item
+On some platforms, @code{lstat("file/",buf)} succeeds instead of
+failing with @code{ENOTDIR}.
+Solaris 9.
@item
On Windows platforms (excluding Cygwin), symlinks are not supported, so
@code{lstat} does not exist.
On platforms where @code{off_t} is a 32-bit type, @code{lstat} may not
correctly report the size of files or block devices larger than 2 GB. The fix
is to use the @code{AC_SYS_LARGEFILE} macro.
+@item
+On Windows platforms (excluding Cygwin), @code{st_ino} is always 0.
+@item
+Because of the definition of @code{struct stat}, it is not possible to
+portably replace @code{stat} via an object-like macro. Therefore,
+expressions such as @code{(islnk ? lstat : stat) (name, buf)} are not
+portable, and should instead be written @code{islnk ? lstat (name,
+buf) : stat (name, buf)}.
@end itemize
/* Work around a bug of lstat on some systems
- Copyright (C) 1997-1999, 2000-2006, 2008 Free Software Foundation, Inc.
+ Copyright (C) 1997-1999, 2000-2006, 2008-2009 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
#include <config.h>
-/* Get the original definition of open. It might be defined as a macro. */
+/* Get the original definition of lstat. It might be defined as a macro. */
#define __need_system_sys_stat_h
#include <sys/types.h>
#include <sys/stat.h>
size_t len;
int lstat_result = orig_lstat (file, sbuf);
- if (lstat_result != 0 || !S_ISLNK (sbuf->st_mode))
+ if (lstat_result != 0)
return lstat_result;
+ /* This replacement file can blindly check against '/' rather than
+ using the ISSLASH macro, because all platforms with '\\' either
+ lack symlinks (mingw) or have working lstat (cygwin) and thus do
+ not compile this file. 0 len should have already been filtered
+ out above, with a failure return of ENOENT. */
len = strlen (file);
- if (len == 0 || file[len - 1] != '/')
+ if (file[len - 1] != '/' || S_ISDIR (sbuf->st_mode))
return 0;
- /* FILE refers to a symbolic link and the name ends with a slash.
- Call stat() to get info about the link's referent. */
-
- /* If stat fails, then we do the same. */
- if (stat (file, sbuf) != 0)
- return -1;
-
- /* If FILE references a directory, return 0. */
- if (S_ISDIR (sbuf->st_mode))
- return 0;
-
- /* Here, we know stat succeeded and FILE references a non-directory.
- But it was specified via a name including a trailing slash.
- Fail with errno set to ENOTDIR to indicate the contradiction. */
- errno = ENOTDIR;
- return -1;
+ /* At this point, a trailing slash is only permitted on
+ symlink-to-dir; but it should have found information on the
+ directory, not the symlink. Call stat() to get info about the
+ link's referent. Our replacement stat guarantees valid results,
+ even if the symlink is not pointing to a directory. */
+ if (!S_ISLNK (sbuf->st_mode))
+ {
+ errno = ENOTDIR;
+ return -1;
+ }
+ return stat (file, sbuf);
}
/* Test of lstat() function.
- Copyright (C) 2008 Free Software Foundation, Inc.
+ Copyright (C) 2008, 2009 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
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
-/* Written by Simon Josefsson, 2008. */
+/* Written by Simon Josefsson, 2008; and Eric Blake, 2009. */
#include <config.h>
#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "same-inode.h"
+
+#if !HAVE_SYMLINK
+# define symlink(a,b) (-1)
+#endif
+
+#define ASSERT(expr) \
+ do \
+ { \
+ if (!(expr)) \
+ { \
+ fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
+ fflush (stderr); \
+ abort (); \
+ } \
+ } \
+ while (0)
+
+#define BASE "test-lstat.t"
int
-main (int argc, char **argv)
+main ()
{
- struct stat buf;
+ struct stat st1;
+ struct stat st2;
+
+ /* Remove any leftovers from a previous partial run. */
+ ASSERT (system ("rm -rf " BASE "*") == 0);
+
+ /* Test for common directories. */
+ ASSERT (lstat (".", &st1) == 0);
+ ASSERT (lstat ("./", &st2) == 0);
+ ASSERT (SAME_INODE (st1, st2));
+ ASSERT (S_ISDIR (st1.st_mode));
+ ASSERT (S_ISDIR (st2.st_mode));
+ ASSERT (lstat ("/", &st1) == 0);
+ ASSERT (lstat ("///", &st2) == 0);
+ ASSERT (SAME_INODE (st1, st2));
+ ASSERT (S_ISDIR (st1.st_mode));
+ ASSERT (S_ISDIR (st2.st_mode));
+ ASSERT (lstat ("..", &st1) == 0);
+ ASSERT (S_ISDIR (st1.st_mode));
+
+ /* Test for error conditions. */
+ errno = 0;
+ ASSERT (lstat ("", &st1) == -1);
+ ASSERT (errno == ENOENT);
+ errno = 0;
+ ASSERT (lstat ("nosuch", &st1) == -1);
+ ASSERT (errno == ENOENT);
+ errno = 0;
+ ASSERT (lstat ("nosuch/", &st1) == -1);
+ ASSERT (errno == ENOENT);
- if (lstat ("/", &buf) != 0)
+ ASSERT (close (creat (BASE "file", 0600)) == 0);
+ ASSERT (lstat (BASE "file", &st1) == 0);
+ ASSERT (S_ISREG (st1.st_mode));
+ errno = 0;
+ ASSERT (lstat (BASE "file/", &st1) == -1);
+ ASSERT (errno == ENOTDIR);
+
+ /* Now for some symlink tests, where supported. We set up:
+ link1 -> directory
+ link2 -> file
+ link3 -> dangling
+ link4 -> loop
+ then test behavior both with and without trailing slash.
+ */
+ if (symlink (".", BASE "link1") != 0)
{
- perror ("lstat");
- return 1;
+ ASSERT (unlink (BASE "file") == 0);
+ fputs ("skipping test: symlinks not supported on this filesystem\n",
+ stderr);
+ return 77;
}
+ ASSERT (symlink (BASE "file", BASE "link2") == 0);
+ ASSERT (symlink (BASE "nosuch", BASE "link3") == 0);
+ ASSERT (symlink (BASE "link4", BASE "link4") == 0);
+
+ ASSERT (lstat (BASE "link1", &st1) == 0);
+ ASSERT (S_ISLNK (st1.st_mode));
+ ASSERT (lstat (BASE "link1/", &st1) == 0);
+ ASSERT (stat (BASE "link1", &st2) == 0);
+ ASSERT (S_ISDIR (st1.st_mode));
+ ASSERT (S_ISDIR (st2.st_mode));
+ ASSERT (SAME_INODE (st1, st2));
+
+ ASSERT (lstat (BASE "link2", &st1) == 0);
+ ASSERT (S_ISLNK (st1.st_mode));
+ errno = 0;
+ ASSERT (lstat (BASE "link2/", &st1) == -1);
+ ASSERT (errno == ENOTDIR);
+
+ ASSERT (lstat (BASE "link3", &st1) == 0);
+ ASSERT (S_ISLNK (st1.st_mode));
+ errno = 0;
+ ASSERT (lstat (BASE "link3/", &st1) == -1);
+ ASSERT (errno == ENOENT);
+
+ ASSERT (lstat (BASE "link4", &st1) == 0);
+ ASSERT (S_ISLNK (st1.st_mode));
+ errno = 0;
+ ASSERT (lstat (BASE "link4/", &st1) == -1);
+ ASSERT (errno == ELOOP);
+
+ /* Cleanup. */
+ ASSERT (unlink (BASE "file") == 0);
+ ASSERT (unlink (BASE "link1") == 0);
+ ASSERT (unlink (BASE "link2") == 0);
+ ASSERT (unlink (BASE "link3") == 0);
+ ASSERT (unlink (BASE "link4") == 0);
return 0;
}
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