[apple/file_cmds.git] / ln / ln.c

/*-
 * Copyright (c) 1987, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if 0
#ifndef lint
static char const copyright[] =
"@(#) Copyright (c) 1987, 1993, 1994\n\
	The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)ln.c	8.2 (Berkeley) 3/31/94";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/bin/ln/ln.c,v 1.34 2006/02/14 11:08:05 glebius Exp $");

#include <sys/param.h>
#include <sys/stat.h>

#include <err.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

int	fflag;				/* Unlink existing files. */
int	Fflag;				/* Remove empty directories also. */
int	hflag;				/* Check new name for symlink first. */
int	iflag;				/* Interactive mode. */
int	sflag;				/* Symbolic, not hard, link. */
int	vflag;				/* Verbose output. */
					/* System link call. */
int (*linkf)(const char *, const char *);
char	linkch;

int	linkit(const char *, const char *, int);
void	usage(void);

int
main(int argc, char *argv[])
{
	struct stat sb;
	char *p, *sourcedir;
	int ch, exitval;

	if (argc < 1)
		usage();
	/*
	 * Test for the special case where the utility is called as
	 * "link", for which the functionality provided is greatly
	 * simplified.
	 */
	if ((p = rindex(argv[0], '/')) == NULL)
		p = argv[0];
	else
		++p;
	if (strcmp(p, "link") == 0) {
		while (getopt(argc, argv, "") != -1)
			usage();
		argc -= optind;
		argv += optind;
		if (argc != 2)
			usage();
		linkf = link;
		exit(linkit(argv[0], argv[1], 0));
	}

	while ((ch = getopt(argc, argv, "Ffhinsv")) != -1)
		switch (ch) {
		case 'F':
			Fflag = 1;
			break;
		case 'f':
			fflag = 1;
			iflag = 0;
			break;
		case 'h':
		case 'n':
			hflag = 1;
			break;
		case 'i':
			iflag = 1;
			fflag = 0;
			break;
		case 's':
			sflag = 1;
			break;
		case 'v':
			vflag = 1;
			break;
		case '?':
		default:
			usage();
		}

	argv += optind;
	argc -= optind;

	linkf = sflag ? symlink : link;
	linkch = sflag ? '-' : '=';
	if (sflag == 0)
		Fflag = 0;
	if (Fflag == 1 && iflag == 0)
		fflag = 1;

	switch(argc) {
	case 0:
		usage();
		/* NOTREACHED */
	case 1:				/* ln target */
		exit(linkit(argv[0], ".", 1));
	case 2:				/* ln target source */
		exit(linkit(argv[0], argv[1], 0));
	default:
		;
	}
					/* ln target1 target2 directory */
	sourcedir = argv[argc - 1];
	if (hflag && lstat(sourcedir, &sb) == 0 && S_ISLNK(sb.st_mode)) {
		/*
		 * We were asked not to follow symlinks, but found one at
		 * the target--simulate "not a directory" error
		 */
		errno = ENOTDIR;
		err(1, "%s", sourcedir);
	}
	if (stat(sourcedir, &sb))
		err(1, "%s", sourcedir);
	if (!S_ISDIR(sb.st_mode))
		usage();
	for (exitval = 0; *argv != sourcedir; ++argv)
		exitval |= linkit(*argv, sourcedir, 1);
	exit(exitval);
}

int
linkit(const char *target, const char *source, int isdir)
{
	struct stat sb;
	const char *p;
	int ch, exists, first;
	char path[PATH_MAX];

	if (!sflag) {
		/* If target doesn't exist, quit now. */
		if (stat(target, &sb)) {
			warn("%s", target);
			return (1);
		}
		/* Only symbolic links to directories. */
		if (S_ISDIR(sb.st_mode)) {
			errno = EISDIR;
			warn("%s", target);
			return (1);
		}
	}

	/*
	 * If the source is a directory (and not a symlink if hflag),
	 * append the target's name.
	 */
	if (isdir ||
	    (lstat(source, &sb) == 0 && S_ISDIR(sb.st_mode)) ||
	    (!hflag && stat(source, &sb) == 0 && S_ISDIR(sb.st_mode))) {
		if ((p = strrchr(target, '/')) == NULL)
			p = target;
		else
			++p;
		if (snprintf(path, sizeof(path), "%s/%s", source, p) >=
		    (ssize_t)sizeof(path)) {
			errno = ENAMETOOLONG;
			warn("%s", target);
			return (1);
		}
		source = path;
	}

	exists = !lstat(source, &sb);
	/*
	 * If the file exists, then unlink it forcibly if -f was specified
	 * and interactively if -i was specified.
	 */
	if (fflag && exists) {
		if (Fflag && S_ISDIR(sb.st_mode)) {
			if (rmdir(source)) {
				warn("%s", source);
				return (1);
			}
		} else if (unlink(source)) {
			warn("%s", source);
			return (1);
		}
	} else if (iflag && exists) {
		fflush(stdout);
		fprintf(stderr, "replace %s? ", source);

		first = ch = getchar();
		while(ch != '\n' && ch != EOF)
			ch = getchar();
		if (first != 'y' && first != 'Y') {
			fprintf(stderr, "not replaced\n");
			return (1);
		}

		if (Fflag && S_ISDIR(sb.st_mode)) {
			if (rmdir(source)) {
				warn("%s", source);
				return (1);
			}
		} else if (unlink(source)) {
			warn("%s", source);
			return (1);
		}
	}

	/* Attempt the link. */
	if ((*linkf)(target, source)) {
		warn("%s", source);
		return (1);
	}
	if (vflag)
		(void)printf("%s %c> %s\n", source, linkch, target);
	return (0);
}

void
usage(void)
{
	(void)fprintf(stderr, "%s\n%s\n%s\n",
	    "usage: ln [-Ffhinsv] source_file [target_file]",
	    "       ln [-Ffhinsv] source_file ... target_dir",
	    "       link source_file target_file");
	exit(1);
}
Commit	Line	Data
864a4b6e	1	/*-
44a7a5ab A	2	* Copyright (c) 1987, 1993, 1994
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
44a7a5ab A	13	* 4. Neither the name of the University nor the names of its contributors
	14	* may be used to endorse or promote products derived from this software
	15	* without specific prior written permission.
	16	*
	17	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	18	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	19	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	20	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	21	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	22	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	23	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	24	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	25	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	26	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	27	* SUCH DAMAGE.
	28	*/
	29
864a4b6e	30	#if 0
44a7a5ab	31	#ifndef lint
6c780a1f A	32	static char const copyright[] =
	33	"@(#) Copyright (c) 1987, 1993, 1994\n\
	34	The Regents of the University of California. All rights reserved.\n";
44a7a5ab A	35	#endif /* not lint */
	36
	37	#ifndef lint
44a7a5ab	38	static char sccsid[] = "@(#)ln.c 8.2 (Berkeley) 3/31/94";
44a7a5ab	39	#endif /* not lint */
864a4b6e	40	#endif
6c780a1f	41	#include <sys/cdefs.h>
864a4b6e	42	__FBSDID("$FreeBSD: src/bin/ln/ln.c,v 1.34 2006/02/14 11:08:05 glebius Exp $");
44a7a5ab A	43
	44	#include <sys/param.h>
	45	#include <sys/stat.h>
	46
	47	#include <err.h>
	48	#include <errno.h>
6c780a1f	49	#include <limits.h>
44a7a5ab A	50	#include <stdio.h>
	51	#include <stdlib.h>
	52	#include <string.h>
	53	#include <unistd.h>
	54
	55	int fflag; /* Unlink existing files. */
864a4b6e	56	int Fflag; /* Remove empty directories also. */
44a7a5ab	57	int hflag; /* Check new name for symlink first. */
6c780a1f	58	int iflag; /* Interactive mode. */
44a7a5ab	59	int sflag; /* Symbolic, not hard, link. */
6c780a1f	60	int vflag; /* Verbose output. */
44a7a5ab	61	/* System link call. */
6c780a1f A	62	int (linkf)(const char , const char *);
6c780a1f A	63	char linkch;
44a7a5ab	64
6c780a1f A	65	int linkit(const char , const char , int);
6c780a1f A	66	void usage(void);
44a7a5ab A	67
44a7a5ab A	68	int
6c780a1f	69	main(int argc, char *argv[])
44a7a5ab A	70	{
44a7a5ab A	71	struct stat sb;
6c780a1f	72	char p, sourcedir;
44a7a5ab	73	int ch, exitval;
44a7a5ab	74
864a4b6e A	75	if (argc < 1)
864a4b6e A	76	usage();
6c780a1f A	77	/*
	78	* Test for the special case where the utility is called as
	79	* "link", for which the functionality provided is greatly
	80	* simplified.
	81	*/
	82	if ((p = rindex(argv[0], '/')) == NULL)
	83	p = argv[0];
	84	else
	85	++p;
	86	if (strcmp(p, "link") == 0) {
	87	while (getopt(argc, argv, "") != -1)
	88	usage();
	89	argc -= optind;
	90	argv += optind;
	91	if (argc != 2)
	92	usage();
	93	linkf = link;
	94	exit(linkit(argv[0], argv[1], 0));
	95	}
	96
864a4b6e	97	while ((ch = getopt(argc, argv, "Ffhinsv")) != -1)
44a7a5ab	98	switch (ch) {
864a4b6e A	99	case 'F':
	100	Fflag = 1;
	101	break;
44a7a5ab A	102	case 'f':
44a7a5ab A	103	fflag = 1;
6c780a1f	104	iflag = 0;
44a7a5ab A	105	break;
	106	case 'h':
	107	case 'n':
	108	hflag = 1;
	109	break;
6c780a1f A	110	case 'i':
	111	iflag = 1;
	112	fflag = 0;
	113	break;
44a7a5ab A	114	case 's':
	115	sflag = 1;
	116	break;
6c780a1f A	117	case 'v':
	118	vflag = 1;
	119	break;
44a7a5ab A	120	case '?':
	121	default:
	122	usage();
	123	}
	124
	125	argv += optind;
	126	argc -= optind;
	127
	128	linkf = sflag ? symlink : link;
6c780a1f	129	linkch = sflag ? '-' : '=';
864a4b6e A	130	if (sflag == 0)
	131	Fflag = 0;
	132	if (Fflag == 1 && iflag == 0)
	133	fflag = 1;
44a7a5ab A	134
	135	switch(argc) {
	136	case 0:
	137	usage();
	138	/* NOTREACHED */
	139	case 1: /* ln target */
	140	exit(linkit(argv[0], ".", 1));
44a7a5ab A	141	case 2: /* ln target source */
44a7a5ab A	142	exit(linkit(argv[0], argv[1], 0));
6c780a1f A	143	default:
6c780a1f A	144	;
44a7a5ab A	145	}
	146	/* ln target1 target2 directory */
	147	sourcedir = argv[argc - 1];
	148	if (hflag && lstat(sourcedir, &sb) == 0 && S_ISLNK(sb.st_mode)) {
6c780a1f A	149	/*
	150	* We were asked not to follow symlinks, but found one at
	151	* the target--simulate "not a directory" error
	152	*/
44a7a5ab A	153	errno = ENOTDIR;
	154	err(1, "%s", sourcedir);
	155	}
	156	if (stat(sourcedir, &sb))
	157	err(1, "%s", sourcedir);
	158	if (!S_ISDIR(sb.st_mode))
	159	usage();
	160	for (exitval = 0; *argv != sourcedir; ++argv)
	161	exitval \|= linkit(*argv, sourcedir, 1);
	162	exit(exitval);
44a7a5ab A	163	}
	164
	165	int
6c780a1f	166	linkit(const char target, const char source, int isdir)
44a7a5ab A	167	{
44a7a5ab A	168	struct stat sb;
6c780a1f A	169	const char *p;
	170	int ch, exists, first;
	171	char path[PATH_MAX];
44a7a5ab A	172
	173	if (!sflag) {
	174	/* If target doesn't exist, quit now. */
	175	if (stat(target, &sb)) {
	176	warn("%s", target);
	177	return (1);
	178	}
6c780a1f A	179	/* Only symbolic links to directories. */
	180	if (S_ISDIR(sb.st_mode)) {
	181	errno = EISDIR;
	182	warn("%s", target);
	183	return (1);
	184	}
44a7a5ab A	185	}
44a7a5ab A	186
6c780a1f A	187	/*
	188	* If the source is a directory (and not a symlink if hflag),
	189	* append the target's name.
	190	*/
44a7a5ab	191	if (isdir \|\|
6c780a1f A	192	(lstat(source, &sb) == 0 && S_ISDIR(sb.st_mode)) \|\|
6c780a1f A	193	(!hflag && stat(source, &sb) == 0 && S_ISDIR(sb.st_mode))) {
44a7a5ab A	194	if ((p = strrchr(target, '/')) == NULL)
	195	p = target;
	196	else
	197	++p;
6c780a1f A	198	if (snprintf(path, sizeof(path), "%s/%s", source, p) >=
	199	(ssize_t)sizeof(path)) {
	200	errno = ENAMETOOLONG;
	201	warn("%s", target);
	202	return (1);
	203	}
44a7a5ab A	204	source = path;
	205	}
	206
6c780a1f	207	exists = !lstat(source, &sb);
44a7a5ab	208	/*
6c780a1f A	209	* If the file exists, then unlink it forcibly if -f was specified
6c780a1f A	210	* and interactively if -i was specified.
44a7a5ab	211	*/
6c780a1f	212	if (fflag && exists) {
864a4b6e A	213	if (Fflag && S_ISDIR(sb.st_mode)) {
	214	if (rmdir(source)) {
	215	warn("%s", source);
	216	return (1);
	217	}
	218	} else if (unlink(source)) {
6c780a1f A	219	warn("%s", source);
	220	return (1);
	221	}
	222	} else if (iflag && exists) {
	223	fflush(stdout);
	224	fprintf(stderr, "replace %s? ", source);
	225
	226	first = ch = getchar();
	227	while(ch != '\n' && ch != EOF)
	228	ch = getchar();
	229	if (first != 'y' && first != 'Y') {
	230	fprintf(stderr, "not replaced\n");
	231	return (1);
	232	}
	233
864a4b6e A	234	if (Fflag && S_ISDIR(sb.st_mode)) {
	235	if (rmdir(source)) {
	236	warn("%s", source);
	237	return (1);
	238	}
	239	} else if (unlink(source)) {
6c780a1f A	240	warn("%s", source);
	241	return (1);
	242	}
	243	}
	244
	245	/* Attempt the link. */
	246	if ((*linkf)(target, source)) {
44a7a5ab A	247	warn("%s", source);
	248	return (1);
	249	}
6c780a1f A	250	if (vflag)
6c780a1f A	251	(void)printf("%s %c> %s\n", source, linkch, target);
44a7a5ab A	252	return (0);
	253	}
	254
	255	void
6c780a1f	256	usage(void)
44a7a5ab	257	{
6c780a1f	258	(void)fprintf(stderr, "%s\n%s\n%s\n",
864a4b6e A	259	"usage: ln [-Ffhinsv] source_file [target_file]",
	260	" ln [-Ffhinsv] source_file ... target_dir",
	261	" link source_file target_file");
44a7a5ab	262	exit(1);
44a7a5ab	263	}