110 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			110 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* vi: set sw=4 ts=4: */
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| /*
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|  * Mini ln implementation for busybox
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|  *
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|  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
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|  *
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|  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
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|  */
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| 
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| /* BB_AUDIT SUSv3 compliant */
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| /* BB_AUDIT GNU options missing: -d, -F, -i, and -v. */
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| /* http://www.opengroup.org/onlinepubs/007904975/utilities/ln.html */
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| 
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| #include "libbb.h"
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| 
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| /* This is a NOEXEC applet. Be very careful! */
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| 
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| 
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| #define LN_SYMLINK          1
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| #define LN_FORCE            2
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| #define LN_NODEREFERENCE    4
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| #define LN_BACKUP           8
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| #define LN_SUFFIX           16
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| 
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| int ln_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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| int ln_main(int argc, char **argv)
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| {
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| 	int status = EXIT_SUCCESS;
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| 	int flag;
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| 	char *last;
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| 	char *src_name;
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| 	char *src;
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| 	char *suffix = (char*)"~";
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| 	struct stat statbuf;
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| 	int (*link_func)(const char *, const char *);
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| 
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| 	flag = getopt32(argv, "sfnbS:", &suffix);
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| 
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| 	if (argc == optind) {
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| 		bb_show_usage();
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| 	}
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| 
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| 	last = argv[argc - 1];
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| 	argv += optind;
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| 
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| 	if (argc == optind + 1) {
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| 		*--argv = last;
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| 		last = bb_get_last_path_component_strip(xstrdup(last));
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| 	}
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| 
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| 	do {
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| 		src_name = NULL;
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| 		src = last;
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| 
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| 		if (is_directory(src,
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| 		                (flag & LN_NODEREFERENCE) ^ LN_NODEREFERENCE,
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| 		                NULL)
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| 		) {
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| 			src_name = xstrdup(*argv);
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| 			src = concat_path_file(src, bb_get_last_path_component_strip(src_name));
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| 			free(src_name);
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| 			src_name = src;
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| 		}
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| 		if (!(flag & LN_SYMLINK) && stat(*argv, &statbuf)) {
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| 			// coreutils: "ln dangling_symlink new_hardlink" works
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| 			if (lstat(*argv, &statbuf) || !S_ISLNK(statbuf.st_mode)) {
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| 				bb_simple_perror_msg(*argv);
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| 				status = EXIT_FAILURE;
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| 				free(src_name);
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| 				continue;
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| 			}
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| 		}
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| 
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| 		if (flag & LN_BACKUP) {
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| 			char *backup;
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| 			backup = xasprintf("%s%s", src, suffix);
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| 			if (rename(src, backup) < 0 && errno != ENOENT) {
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| 				bb_simple_perror_msg(src);
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| 				status = EXIT_FAILURE;
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| 				free(backup);
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| 				continue;
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| 			}
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| 			free(backup);
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| 			/*
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| 			 * When the source and dest are both hard links to the same
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| 			 * inode, a rename may succeed even though nothing happened.
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| 			 * Therefore, always unlink().
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| 			 */
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| 			unlink(src);
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| 		} else if (flag & LN_FORCE) {
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| 			unlink(src);
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| 		}
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| 
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| 		link_func = link;
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| 		if (flag & LN_SYMLINK) {
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| 			link_func = symlink;
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| 		}
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| 
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| 		if (link_func(*argv, src) != 0) {
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| 			bb_simple_perror_msg(src);
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| 			status = EXIT_FAILURE;
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| 		}
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| 
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| 		free(src_name);
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| 
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| 	} while ((++argv)[1]);
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| 
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| 	return status;
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| }
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