/* `ln' program to create links between files.
- Copyright (C) 86, 89, 90, 91, 1995-2004 Free Software Foundation, Inc.
+ Copyright (C) 1986, 1989-1991, 1995-2006 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, write to the Free Software Foundation,
- Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
\f
/* Written by Mike Parker and David MacKenzie. */
#include "backupfile.h"
#include "dirname.h"
#include "error.h"
+#include "filenamecat.h"
#include "quote.h"
#include "yesno.h"
# define ENABLE_HARD_LINK_TO_SYMLINK_WARNING 0
#endif
-int link (); /* Some systems don't declare this anywhere. */
-
-#ifdef S_ISLNK
-int symlink ();
-#endif
-
/* In being careful not even to try to make hard links to directories,
we have to know whether link(2) follows symlinks. If it does, then
we have to *stat* the `source' to see if the resulting link would be
lstat (File, Stat_buf)
#endif
-/* Construct a string NEW_DEST by concatenating DEST, a slash, and
- basename(SOURCE) in alloca'd memory. Don't modify DEST or SOURCE. */
-
-#define PATH_BASENAME_CONCAT(new_dest, dest, source) \
- do \
- { \
- const char *source_base; \
- char *tmp_source; \
- size_t buf_len = strlen (source) + 1; \
- \
- tmp_source = alloca (buf_len); \
- memcpy (tmp_source, (source), buf_len); \
- strip_trailing_slashes (tmp_source); \
- source_base = base_name (tmp_source); \
- \
- (new_dest) = alloca (strlen ((dest)) + 1 \
- + strlen (source_base) + 1); \
- stpcpy (stpcpy (stpcpy ((new_dest), (dest)), "/"), source_base);\
- } \
- while (0)
-
/* The name by which the program was run, for error messages. */
char *program_name;
/* FIXME: document */
static enum backup_type backup_type;
-/* A pointer to the function used to make links. This will point to either
- `link' or `symlink'. */
-static int (*linkfunc) ();
+/* If true, make symbolic links; otherwise, make hard links. */
+static bool symbolic_link;
-/* If nonzero, make symbolic links; otherwise, make hard links. */
-static int symbolic_link;
+/* If true, ask the user before removing existing files. */
+static bool interactive;
-/* If nonzero, ask the user before removing existing files. */
-static int interactive;
+/* If true, remove existing files unconditionally. */
+static bool remove_existing_files;
-/* If nonzero, remove existing files unconditionally. */
-static int remove_existing_files;
+/* If true, list each file as it is moved. */
+static bool verbose;
-/* If nonzero, list each file as it is moved. */
-static int verbose;
-
-/* If nonzero, allow the superuser to *attempt* to make hard links
+/* If true, allow the superuser to *attempt* to make hard links
to directories. However, it appears that this option is not useful
in practice, since even the superuser is prohibited from hard-linking
directories on most (all?) existing systems. */
-static int hard_dir_link;
+static bool hard_dir_link;
/* If nonzero, and the specified destination is a symbolic link to a
directory, treat it just as if it were a directory. Otherwise, the
command `ln --force --no-dereference file symlink-to-dir' deletes
symlink-to-dir before creating the new link. */
-static int dereference_dest_dir_symlinks = 1;
+static bool dereference_dest_dir_symlinks = true;
static struct option const long_options[] =
{
{"target-directory", required_argument, NULL, 't'},
{"symbolic", no_argument, NULL, 's'},
{"verbose", no_argument, NULL, 'v'},
- {"version-control", required_argument, NULL, 'V'}, /* Deprecated. FIXME. */
{GETOPT_HELP_OPTION_DECL},
{GETOPT_VERSION_OPTION_DECL},
{NULL, 0, NULL, 0}
static bool
target_directory_operand (char const *file)
{
- char const *b = base_name (file);
+ char const *b = last_component (file);
size_t blen = strlen (b);
bool looks_like_a_dir = (blen == 0 || ISSLASH (b[blen - 1]));
struct stat st;
/* Make a link DEST to the (usually) existing file SOURCE.
Symbolic links to nonexistent files are allowed.
- If DEST_IS_DIR, put the link to SOURCE in the DEST directory.
- Return 1 if there is an error, otherwise 0. */
+ Return true if successful. */
-static int
-do_link (const char *source, const char *dest, bool dest_is_dir)
+static bool
+do_link (const char *source, const char *dest)
{
struct stat source_stats;
struct stat dest_stats;
char *dest_backup = NULL;
- int lstat_status = -1;
+ bool lstat_ok = false;
+ bool source_is_dir = false;
+ bool ok;
/* Use stat here instead of lstat.
On SVR4, link does not follow symlinks, so this check disallows
if (STAT_LIKE_LINK (source, &source_stats) != 0)
{
error (0, errno, _("accessing %s"), quote (source));
- return 1;
+ return false;
}
if (ENABLE_HARD_LINK_TO_SYMLINK_WARNING
quote (source));
}
- if (!hard_dir_link && S_ISDIR (source_stats.st_mode))
+ if (S_ISDIR (source_stats.st_mode))
{
- error (0, 0, _("%s: hard link not allowed for directory"),
- quote (source));
- return 1;
+ source_is_dir = true;
+ if (! hard_dir_link)
+ {
+ error (0, 0, _("%s: hard link not allowed for directory"),
+ quote (source));
+ return false;
+ }
}
}
- if (dest_is_dir)
+ if (remove_existing_files || interactive || backup_type != no_backups)
{
- /* Treat DEST as a directory; build the full filename. */
- char *new_dest;
- PATH_BASENAME_CONCAT (new_dest, dest, source);
- dest = new_dest;
- }
-
- if (remove_existing_files || interactive || backup_type != none)
- {
- lstat_status = lstat (dest, &dest_stats);
- if (lstat_status != 0 && errno != ENOENT)
+ lstat_ok = (lstat (dest, &dest_stats) == 0);
+ if (!lstat_ok && errno != ENOENT)
{
error (0, errno, _("accessing %s"), quote (dest));
- return 1;
+ return false;
}
}
But if the source and destination are the same, don't remove
anything and fail right here. */
if (remove_existing_files
- && lstat_status == 0
+ && lstat_ok
/* Allow `ln -sf --backup k k' to succeed in creating the
self-referential symlink, but don't allow the hard-linking
equivalent: `ln -f k k' (with or without --backup) to get
beyond this point, because the error message you'd get is
misleading. */
- && (backup_type == none || !symbolic_link)
+ && (backup_type == no_backups || !symbolic_link)
&& (!symbolic_link || stat (source, &source_stats) == 0)
&& SAME_INODE (source_stats, dest_stats)
/* The following detects whether removing DEST will also remove
{
error (0, 0, _("%s and %s are the same file"),
quote_n (0, source), quote_n (1, dest));
- return 1;
+ return false;
}
- if (lstat_status == 0)
+ if (lstat_ok)
{
if (S_ISDIR (dest_stats.st_mode))
{
error (0, 0, _("%s: cannot overwrite directory"), quote (dest));
- return 1;
+ return false;
}
if (interactive)
{
fprintf (stderr, _("%s: replace %s? "), program_name, quote (dest));
if (!yesno ())
- return 0;
+ return true;
+ remove_existing_files = true;
}
- if (backup_type != none)
+ if (backup_type != no_backups)
{
- char *tmp_backup = find_backup_file_name (dest, backup_type);
- size_t buf_len = strlen (tmp_backup) + 1;
- dest_backup = alloca (buf_len);
- memcpy (dest_backup, tmp_backup, buf_len);
- free (tmp_backup);
- if (rename (dest, dest_backup))
+ dest_backup = find_backup_file_name (dest, backup_type);
+ if (rename (dest, dest_backup) != 0)
{
- if (errno != ENOENT)
+ int rename_errno = errno;
+ free (dest_backup);
+ dest_backup = NULL;
+ if (rename_errno != ENOENT)
{
- error (0, errno, _("cannot backup %s"), quote (dest));
- return 1;
+ error (0, rename_errno, _("cannot backup %s"), quote (dest));
+ return false;
}
- else
- dest_backup = NULL;
}
}
}
- if (verbose)
- {
- printf ((symbolic_link
- ? _("create symbolic link %s to %s")
- : _("create hard link %s to %s")),
- quote_n (0, dest), quote_n (1, source));
- if (dest_backup)
- printf (_(" (backup: %s)"), quote (dest_backup));
- putchar ('\n');
- }
-
- if ((*linkfunc) (source, dest) == 0)
- {
- return 0;
- }
+ ok = ((symbolic_link ? symlink (source, dest) : link (source, dest))
+ == 0);
/* If the attempt to create a link failed and we are removing or
backing up destinations, unlink the destination and try again.
POSIX 1003.1-2004 requires that ln -f A B must unlink B even on
failure (e.g., when A does not exist). This is counterintuitive,
and we submitted a defect report
- <http://www.opengroup.org/sophocles/show_mail.tpl?source=L&listname=austin-review-l&id=1795>
+ <http://www.opengroup.org/austin/mailarchives/ag-review/msg01794.html>
(2004-06-24). If the committee does not fix the standard we'll
have to change the behavior of ln -f, at least if POSIXLY_CORRECT
is set. In the meantime ln -f A B will not unlink B unless the
If we didn't remove DEST in that case, the subsequent LINKFUNC
call would fail. */
- if (errno == EEXIST && (remove_existing_files || dest_backup))
+ if (!ok && errno == EEXIST && (remove_existing_files || dest_backup))
{
if (unlink (dest) != 0)
{
error (0, errno, _("cannot remove %s"), quote (dest));
- return 1;
+ free (dest_backup);
+ return false;
}
- if (linkfunc (source, dest) == 0)
- return 0;
+ ok = ((symbolic_link ? symlink (source, dest) : link (source, dest))
+ == 0);
}
- error (0, errno,
- (symbolic_link
- ? _("creating symbolic link %s to %s")
- : _("creating hard link %s to %s")),
- quote_n (0, dest), quote_n (1, source));
-
- if (dest_backup)
+ if (ok)
{
- if (rename (dest_backup, dest))
- error (0, errno, _("cannot un-backup %s"), quote (dest));
+ if (verbose)
+ {
+ if (dest_backup)
+ printf ("%s ~ ", quote (dest_backup));
+ printf ("%s %c> %s\n", quote_n (0, dest), (symbolic_link ? '-' : '='),
+ quote_n (1, source));
+ }
+ }
+ else
+ {
+ error (0, errno,
+ (symbolic_link
+ ? (errno != ENAMETOOLONG && *source
+ ? _("creating symbolic link %s")
+ : _("creating symbolic link %s -> %s"))
+ : (errno == EMLINK && !source_is_dir
+ ? _("creating hard link to %.0s%s")
+ : (errno == EDQUOT || errno == EEXIST || errno == ENOSPC
+ || errno == EROFS)
+ ? _("creating hard link %s")
+ : _("creating hard link %s => %s"))),
+ quote_n (0, dest), quote_n (1, source));
+
+ if (dest_backup)
+ {
+ if (rename (dest_backup, dest) != 0)
+ error (0, errno, _("cannot un-backup %s"), quote (dest));
+ }
}
- return 1;
+
+ free (dest_backup);
+ return ok;
}
void
-t, --target-directory=DIRECTORY specify the DIRECTORY in which to create\n\
the links\n\
-T, --no-target-directory treat LINK_NAME as a normal file\n\
- -v, --verbose print name of each file before linking\n\
+ -v, --verbose print name of each linked file\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
main (int argc, char **argv)
{
int c;
- int errors;
- int make_backups = 0;
+ bool ok;
+ bool make_backups = false;
char *backup_suffix_string;
char *version_control_string = NULL;
- char *target_directory = NULL;
+ char const *target_directory = NULL;
bool no_target_directory = false;
int n_files;
char **file;
backup_suffix_string = getenv ("SIMPLE_BACKUP_SUFFIX");
symbolic_link = remove_existing_files = interactive = verbose
- = hard_dir_link = 0;
- errors = 0;
+ = hard_dir_link = false;
- while ((c = getopt_long (argc, argv, "bdfinst:vFS:TV:", long_options, NULL))
+ while ((c = getopt_long (argc, argv, "bdfinst:vFS:T", long_options, NULL))
!= -1)
{
switch (c)
{
- case 0: /* Long-named option. */
- break;
-
- case 'V': /* FIXME: this is deprecated. Remove it in 2001. */
- error (0, 0,
- _("warning: --version-control (-V) is obsolete; support for\
- it\nwill be removed in some future release. Use --backup=%s instead."
- ), optarg);
- /* Fall through. */
-
case 'b':
- make_backups = 1;
+ make_backups = true;
if (optarg)
version_control_string = optarg;
break;
case 'd':
case 'F':
- hard_dir_link = 1;
+ hard_dir_link = true;
break;
case 'f':
- remove_existing_files = 1;
- interactive = 0;
+ remove_existing_files = true;
+ interactive = false;
break;
case 'i':
- remove_existing_files = 0;
- interactive = 1;
+ remove_existing_files = false;
+ interactive = true;
break;
case 'n':
- dereference_dest_dir_symlinks = 0;
+ dereference_dest_dir_symlinks = false;
break;
case 's':
#ifdef S_ISLNK
- symbolic_link = 1;
+ symbolic_link = true;
#else
error (EXIT_FAILURE, 0,
_("symbolic links are not supported on this system"));
no_target_directory = true;
break;
case 'v':
- verbose = 1;
+ verbose = true;
break;
case 'S':
- make_backups = 1;
+ make_backups = true;
backup_suffix_string = optarg;
break;
case_GETOPT_HELP_CHAR;
quote (file[n_files - 1]));
}
- if (symbolic_link)
- linkfunc = symlink;
- else
- linkfunc = link;
-
if (backup_suffix_string)
simple_backup_suffix = xstrdup (backup_suffix_string);
backup_type = (make_backups
? xget_version (_("backup type"), version_control_string)
- : none);
+ : no_backups);
if (target_directory)
{
int i;
+ ok = true;
for (i = 0; i < n_files; ++i)
- errors |= do_link (file[i], target_directory, true);
+ {
+ char *dest_base;
+ char *dest = file_name_concat (target_directory,
+ last_component (file[i]),
+ &dest_base);
+ strip_trailing_slashes (dest_base);
+ ok &= do_link (file[i], dest);
+ free (dest);
+ }
}
else
- errors = do_link (file[0], file[1], false);
+ ok = do_link (file[0], file[1]);
- exit (errors == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
+ exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
}