GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: bin/ln/ln.c Lines: 43 72 59.7 %
Date: 2017-11-07 Branches: 41 63 65.1 %

Line Branch Exec Source
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/*	$OpenBSD: ln.c,v 1.24 2016/05/10 20:20:43 tim Exp $	*/
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/*	$NetBSD: ln.c,v 1.10 1995/03/21 09:06:10 cgd Exp $	*/
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/*
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 * Copyright (c) 1987, 1993, 1994
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 *	The Regents of the University of California.  All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <err.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <libgen.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include <limits.h>
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int	fflag;				/* Unlink existing files. */
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int	hflag;				/* Check new name for symlink first. */
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int	Pflag;				/* Hard link to symlink. */
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int	sflag;				/* Symbolic, not hard, link. */
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int	linkit(char *, char *, int);
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void	usage(void) __dead;
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int
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main(int argc, char *argv[])
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{
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	struct stat sb;
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	int ch, exitval;
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	char *sourcedir;
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	if (pledge("stdio rpath cpath flock wpath", NULL) == -1)
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		err(1, "pledge");
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	while ((ch = getopt(argc, argv, "fhLnPs")) != -1)
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		switch (ch) {
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		case 'f':
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			fflag = 1;
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			break;
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		case 'h':
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		case 'n':
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			hflag = 1;
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			break;
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		case 'L':
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			Pflag = 0;
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			break;
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		case 'P':
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			Pflag = 1;
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			break;
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		case 's':
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			sflag = 1;
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			break;
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		default:
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			usage();
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		}
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	argv += optind;
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	argc -= optind;
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	switch(argc) {
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	case 0:
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		usage();
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	case 1:				/* ln target */
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		exit(linkit(argv[0], ".", 1));
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	case 2:				/* ln target source */
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		exit(linkit(argv[0], argv[1], 0));
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	}
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					/* ln target1 target2 directory */
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	sourcedir = argv[argc - 1];
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	if (stat(sourcedir, &sb))
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		err(1, "%s", sourcedir);
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	if (!S_ISDIR(sb.st_mode))
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		usage();
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	for (exitval = 0; *argv != sourcedir; ++argv)
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		exitval |= linkit(*argv, sourcedir, 1);
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	exit(exitval);
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}
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 /*
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  * Nomenclature warning!
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  *
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  * In this source "target" and "source" are used the opposite way they
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  * are used in the ln(1) manual.  Here "target" is the existing file and
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  * "source" specifies the to-be-created link to "target".
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  */
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int
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linkit(char *target, char *source, int isdir)
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{
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	struct stat sb;
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	char *p, path[PATH_MAX];
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	int (*statf)(const char *, struct stat *);
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	int exists, n;
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	if (!sflag) {
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		/* If target doesn't exist, quit now. */
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		if ((Pflag ? lstat : stat)(target, &sb)) {
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			warn("%s", target);
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			return (1);
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		}
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		/* Only symbolic links to directories. */
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		if (S_ISDIR(sb.st_mode)) {
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			warnc(EISDIR, "%s", target);
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			return (1);
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		}
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	}
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	statf = hflag ? lstat : stat;
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	/* If the source is a directory, append the target's name. */
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	if (isdir || (!statf(source, &sb) && S_ISDIR(sb.st_mode))) {
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		if ((p = basename(target)) == NULL) {
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			warn("%s", target);
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			return (1);
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		}
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		n = snprintf(path, sizeof(path), "%s/%s", source, p);
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		if (n < 0 || n >= sizeof(path)) {
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			warnc(ENAMETOOLONG, "%s/%s", source, p);
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			return (1);
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		}
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		source = path;
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	}
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	exists = (lstat(source, &sb) == 0);
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	/*
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	 * If doing hard links and the source (destination) exists and it
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	 * actually is the same file like the target (existing file), we
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	 * complain that the files are identical.  If -f is specified, we
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	 * accept the job as already done and return with success.
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	 */
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	if (exists && !sflag) {
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		struct stat tsb;
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		if ((Pflag ? lstat : stat)(target, &tsb)) {
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			warn("%s: disappeared", target);
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			return (1);
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		}
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		if (tsb.st_dev == sb.st_dev && tsb.st_ino == sb.st_ino) {
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			if (fflag)
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				return (0);
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			else {
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				warnx("%s and %s are identical (nothing done).",
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				    target, source);
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				return (1);
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			}
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		}
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	}
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	/*
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	 * If the file exists, and -f was specified, unlink it.
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	 * Attempt the link.
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	 */
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	if ((fflag && unlink(source) < 0 && errno != ENOENT) ||
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	    (sflag ? symlink(target, source) :
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	    linkat(AT_FDCWD, target, AT_FDCWD, source,
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	    Pflag ? 0 : AT_SYMLINK_FOLLOW))) {
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		warn("%s", source);
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		return (1);
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	}
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	return (0);
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}
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void
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usage(void)
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{
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	extern char *__progname;
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	(void)fprintf(stderr,
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	    "usage: %s [-fhLnPs] source [target]\n"
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	    "       %s [-fLPs] source ... [directory]\n",
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	    __progname, __progname);
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	exit(1);
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}