X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=coreutils%2Fln.c;h=229c682185ef029a0bb80deeacc05b30c23d453e;hb=e2e56c7c4129de7d20df42e8239fd304c81ef29b;hp=0640c666611e9a6d5d475643717864a5cac3ad9d;hpb=cfc0ad4260149f5cdad59c79051c3779d42b2ff5;p=oweals%2Fbusybox.git

diff --git a/coreutils/ln.c b/coreutils/ln.c
index 0640c6666..229c68218 100644
--- a/coreutils/ln.c
+++ b/coreutils/ln.c
@@ -2,7 +2,7 @@
 /*
  * Mini ln implementation for busybox
  *
- * Copyright (C) 1999-2003 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.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
@@ -21,33 +21,33 @@
  */
 
 /* BB_AUDIT SUSv3 compliant */
-/* BB_AUDIT GNU options missing: -b, -d, -F, -i, -S, and -v. */
+/* BB_AUDIT GNU options missing: -d, -F, -i, and -v. */
 /* http://www.opengroup.org/onlinepubs/007904975/utilities/ln.html */
 
-/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
- *
- * Fixed bug involving -n option.  Essentially, -n was always in effect.
- */
-
+#include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <errno.h>
 #include "busybox.h"
 
 #define LN_SYMLINK          1
 #define LN_FORCE            2
 #define LN_NODEREFERENCE    4
+#define LN_BACKUP           8
+#define LN_SUFFIX           16
 
-extern int ln_main(int argc, char **argv)
+int ln_main(int argc, char **argv)
 {
 	int status = EXIT_SUCCESS;
 	int flag;
 	char *last;
 	char *src_name;
 	char *src;
+	char *suffix = "~";
 	struct stat statbuf;
 	int (*link_func)(const char *, const char *);
 
-	flag = bb_getopt_ulflags(argc, argv, "sfn");
+	flag = bb_getopt_ulflags(argc, argv, "sfnbS:", &suffix);
 
 	if (argc == optind) {
 		bb_show_usage();
@@ -73,15 +73,30 @@ extern int ln_main(int argc, char **argv)
 			free(src_name);
 			src_name = src;
 		}
-
-		if (stat(*argv, &statbuf)) {
-			bb_perror_msg(*argv);
+		if (!(flag & LN_SYMLINK) && stat(*argv, &statbuf)) {
+			bb_perror_msg("%s", *argv);
 			status = EXIT_FAILURE;
 			free(src_name);
 			continue;
 		}
 
-		if (flag & LN_FORCE) {
+		if (flag & LN_BACKUP) {
+				char *backup;
+				backup = bb_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);
 		}
 
@@ -89,25 +104,15 @@ extern int ln_main(int argc, char **argv)
 		if (flag & LN_SYMLINK) {
 			link_func = symlink;
 		}
-		
+
 		if (link_func(*argv, src) != 0) {
-			bb_perror_msg(src);
+			bb_perror_msg("%s", src);
 			status = EXIT_FAILURE;
 		}
 
 		free(src_name);
-		
+
 	} while ((++argv)[1]);
 
 	return status;
 }
-
-
-
-
-
-
-
-
-
-