/*
* Mini ln implementation for busybox
*
- * Copyright (C) 1999,2000 by Lineo, inc.
- * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.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
*
*/
-#include "internal.h"
-#define BB_DECLARE_EXTERN
-#define bb_need_name_too_long
-#define bb_need_not_a_directory
-#include "messages.c"
+/* BB_AUDIT SUSv3 compliant */
+/* BB_AUDIT GNU options missing: -d, -F, -i, and -v. */
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/ln.html */
#include <stdio.h>
-#include <dirent.h>
+#include <stdlib.h>
+#include <unistd.h>
#include <errno.h>
+#include "busybox.h"
-static const char ln_usage[] =
- "ln [OPTION] TARGET... LINK_NAME|DIRECTORY\n"
-#ifndef BB_FEATURE_TRIVIAL_HELP
- "\nCreate a link named LINK_NAME or DIRECTORY to the specified TARGET\n\n"
- "Options:\n"
- "\t-s\tmake symbolic links instead of hard links\n"
+#define LN_SYMLINK 1
+#define LN_FORCE 2
+#define LN_NODEREFERENCE 4
+#define LN_BACKUP 8
+#define LN_SUFFIX 16
- "\t-f\tremove existing destination files\n"
- "\t-n\tno dereference symlinks - treat like normal file\n"
-#endif
- ;
-
-static int symlinkFlag = FALSE;
-static int removeoldFlag = FALSE;
-static int followLinks = TRUE;
-
-extern int ln_main(int argc, char **argv)
+int ln_main(int argc, char **argv)
{
- char *linkName;
- int linkIntoDirFlag;
-
- if (argc < 3) {
- usage(ln_usage);
- }
- argc--;
- argv++;
-
- /* Parse any options */
- while (--argc >= 0 && *argv && **argv) {
- while (**argv == '-') {
- while (*++(*argv))
- switch (**argv) {
- case 's':
- symlinkFlag = TRUE;
- break;
- case 'f':
- removeoldFlag = TRUE;
- break;
- case 'n':
- followLinks = FALSE;
- break;
- default:
- usage(ln_usage);
- }
- }
- argv++;
- }
-
- if (argc < 1) {
- fatalError("ln: missing file argument\n");
- }
-
- linkName = argv[argc - 1];
-
- if (strlen(linkName) > BUFSIZ) {
- fprintf(stderr, name_too_long, "ln");
- exit FALSE;
+ 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, "sfnbS:", &suffix);
+
+ if (argc == optind) {
+ bb_show_usage();
}
- linkIntoDirFlag = isDirectory(linkName, TRUE, NULL);
+ last = argv[argc - 1];
+ argv += optind;
- if ((argc > 3) && !linkIntoDirFlag) {
- fprintf(stderr, not_a_directory, "ln", linkName);
- exit FALSE;
+ if (argc == optind + 1) {
+ *--argv = last;
+ last = bb_get_last_path_component(bb_xstrdup(last));
}
- while (argc-- >= 2) {
- char srcName[BUFSIZ + 1];
- int nChars, status;
-
- if (strlen(*argv) > BUFSIZ) {
- fprintf(stderr, name_too_long, "ln");
- exit FALSE;
+ do {
+ src_name = NULL;
+ src = last;
+
+ if (is_directory(src,
+ (flag & LN_NODEREFERENCE) ^ LN_NODEREFERENCE,
+ NULL)) {
+ src_name = bb_xstrdup(*argv);
+ src = concat_path_file(src, bb_get_last_path_component(src_name));
+ free(src_name);
+ src_name = src;
+ }
+ if (!(flag & LN_SYMLINK) && stat(*argv, &statbuf)) {
+ bb_perror_msg("%s", *argv);
+ status = EXIT_FAILURE;
+ free(src_name);
+ continue;
}
- if (followLinks == FALSE) {
- strcpy(srcName, *argv);
- } else {
- /* Warning! This can silently truncate if > BUFSIZ, but
- I don't think that there can be one > BUFSIZ anyway. */
- nChars = readlink(*argv, srcName, BUFSIZ);
- srcName[nChars] = '\0';
+ 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);
}
- if (removeoldFlag == TRUE) {
- status = (unlink(linkName) && errno != ENOENT);
- if (status != 0) {
- perror(linkName);
- exit FALSE;
- }
+ link_func = link;
+ if (flag & LN_SYMLINK) {
+ link_func = symlink;
}
- if (symlinkFlag == TRUE)
- status = symlink(*argv, linkName);
- else
- status = link(*argv, linkName);
- if (status != 0) {
- perror(linkName);
- exit FALSE;
+ if (link_func(*argv, src) != 0) {
+ bb_perror_msg("%s", src);
+ status = EXIT_FAILURE;
}
- }
- exit TRUE;
-}
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+ free(src_name);
+
+ } while ((++argv)[1]);
+
+ return status;
+}
projects / oweals / busybox.git / blobdiff