/*
* Mini ln implementation for busybox
*
- * Copyright (C) 1999,2000 by Lineo, inc. and Erik Andersen
- * Copyright (C) 1999,2000,2001 by Erik Andersen <andersee@debian.org>
- *
- * 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 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, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
-#include <stdio.h>
-#include <dirent.h>
-#include <string.h>
-#include <stdlib.h>
-#include <errno.h>
-#include <unistd.h>
-#include "busybox.h"
+/* BB_AUDIT SUSv3 compliant */
+/* BB_AUDIT GNU options missing: -d, -F, -i, and -v. */
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/ln.html */
+#include "busybox.h"
-static const int LN_SYMLINK = 1;
-static const int LN_FORCE = 2;
-static const int LN_NODEREFERENCE = 4;
+#define LN_SYMLINK 1
+#define LN_FORCE 2
+#define LN_NODEREFERENCE 4
+#define LN_BACKUP 8
+#define LN_SUFFIX 16
-/*
- * linkDestName is where the link points to,
- * linkSrcName is the name of the link to be created.
- */
-static int fs_link(const char *link_destname, const char *link_srcname,
- const int flag)
+int ln_main(int argc, char **argv)
{
- int status;
- int src_is_dir;
- char *src_name = 0;
- const char *src;
-
- if (link_destname==NULL)
- return(FALSE);
-
- if (link_srcname==NULL)
- src = link_destname;
- else
- src = link_srcname;
-
- if (flag&LN_NODEREFERENCE)
- src_is_dir = is_directory(src, TRUE, NULL);
- else
- src_is_dir = is_directory(src, FALSE, NULL);
-
- if ((src_is_dir==TRUE)&&((flag&LN_NODEREFERENCE)==0)) {
- char* srcdir_name;
-
- srcdir_name = xstrdup(link_destname);
- src_name = concat_path_file(src, get_last_path_component(srcdir_name));
- src = src_name;
- free(srcdir_name);
+ int status = EXIT_SUCCESS;
+ int flag;
+ char *last;
+ char *src_name;
+ char *src;
+ char *suffix = (char*)"~";
+ struct stat statbuf;
+ int (*link_func)(const char *, const char *);
+
+ flag = getopt32(argc, argv, "sfnbS:", &suffix);
+
+ if (argc == optind) {
+ bb_show_usage();
}
-
- if (flag&LN_FORCE)
- unlink(src);
-
- if (flag&LN_SYMLINK)
- status = symlink(link_destname, src);
- else
- status = link(link_destname, src);
-
- if (status != 0) {
- perror_msg(src);
- status = FALSE;
- } else {
- status = TRUE;
+
+ last = argv[argc - 1];
+ argv += optind;
+
+ if (argc == optind + 1) {
+ *--argv = last;
+ last = bb_get_last_path_component(xstrdup(last));
}
- free(src_name);
- return status;
-}
-extern int ln_main(int argc, char **argv)
-{
- int status = EXIT_SUCCESS;
- int flag = 0;
- int opt;
-
- /* Parse any options */
- while ((opt=getopt(argc, argv, "sfn")) != -1) {
- switch(opt) {
- case 's':
- flag |= LN_SYMLINK;
- break;
- case 'f':
- flag |= LN_FORCE;
- break;
- case 'n':
- flag |= LN_NODEREFERENCE;
- break;
- default:
- show_usage();
+ do {
+ src_name = NULL;
+ src = last;
+
+ if (is_directory(src,
+ (flag & LN_NODEREFERENCE) ^ LN_NODEREFERENCE,
+ NULL)) {
+ src_name = xstrdup(*argv);
+ src = concat_path_file(src, bb_get_last_path_component(src_name));
+ free(src_name);
+ src_name = src;
}
- }
- if (optind > (argc-1)) {
- show_usage();
- }
- if (optind == (argc-1)) {
- if (fs_link(argv[optind],
- get_last_path_component(argv[optind]), flag)==FALSE)
- status = EXIT_FAILURE;
- }
- while(optind<(argc-1)) {
- if (fs_link(argv[optind], argv[argc-1], flag)==FALSE)
+ if (!(flag & LN_SYMLINK) && stat(*argv, &statbuf)) {
+ // coreutils: "ln dangling_symlink new_hardlink" works
+ if (lstat(*argv, &statbuf) || !S_ISLNK(statbuf.st_mode)) {
+ bb_perror_msg("%s", *argv);
+ status = EXIT_FAILURE;
+ free(src_name);
+ continue;
+ }
+ }
+
+ if (flag & LN_BACKUP) {
+ char *backup;
+ backup = xasprintf("%s%s", src, suffix);
+ if (rename(src, backup) < 0 && errno != ENOENT) {
+ bb_perror_msg("%s", src);
+ status = EXIT_FAILURE;
+ free(backup);
+ continue;
+ }
+ free(backup);
+ /*
+ * When the source and dest are both hard links to the same
+ * inode, a rename may succeed even though nothing happened.
+ * Therefore, always unlink().
+ */
+ unlink(src);
+ } else if (flag & LN_FORCE) {
+ unlink(src);
+ }
+
+ link_func = link;
+ if (flag & LN_SYMLINK) {
+ link_func = symlink;
+ }
+
+ if (link_func(*argv, src) != 0) {
+ bb_perror_msg("%s", src);
status = EXIT_FAILURE;
- optind++;
- }
+ }
+
+ free(src_name);
+
+ } while ((++argv)[1]);
+
return status;
}
-
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
projects / oweals / busybox.git / blobdiff