[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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 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.
 */

#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
#if 0
static char sccsid[] = "@(#)ln.c	8.2 (Berkeley) 3/31/94";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__RCSID("$FreeBSD: src/bin/ln/ln.c,v 1.29 2002/07/31 16:53:59 markm 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	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;

	/*
	 * 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, "fhinsv")) != -1)
		switch (ch) {
		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 ? '-' : '=';

	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 (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 (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 [-fhinsv] file1 file2",
	    "       ln [-fhinsv] file ... directory",
	    "       link file1 file2");
	exit(1);
}
Commit	Line	Data
44a7a5ab A	1	/*
	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.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. Neither the name of the University nor the names of its contributors
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	22	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	25	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	26	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	27	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	28	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	29	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	30	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	31	* SUCH DAMAGE.
	32	*/
	33
44a7a5ab	34	#ifndef lint
6c780a1f A	35	static char const copyright[] =
	36	"@(#) Copyright (c) 1987, 1993, 1994\n\
	37	The Regents of the University of California. All rights reserved.\n";
44a7a5ab A	38	#endif /* not lint */
	39
	40	#ifndef lint
	41	#if 0
	42	static char sccsid[] = "@(#)ln.c 8.2 (Berkeley) 3/31/94";
44a7a5ab A	43	#endif
44a7a5ab A	44	#endif /* not lint */
6c780a1f A	45	#include <sys/cdefs.h>
6c780a1f A	46	__RCSID("$FreeBSD: src/bin/ln/ln.c,v 1.29 2002/07/31 16:53:59 markm Exp $");
44a7a5ab A	47
	48	#include <sys/param.h>
	49	#include <sys/stat.h>
	50
	51	#include <err.h>
	52	#include <errno.h>
6c780a1f	53	#include <limits.h>
44a7a5ab A	54	#include <stdio.h>
	55	#include <stdlib.h>
	56	#include <string.h>
	57	#include <unistd.h>
	58
	59	int fflag; /* Unlink existing files. */
	60	int hflag; /* Check new name for symlink first. */
6c780a1f	61	int iflag; /* Interactive mode. */
44a7a5ab	62	int sflag; /* Symbolic, not hard, link. */
6c780a1f	63	int vflag; /* Verbose output. */
44a7a5ab	64	/* System link call. */
6c780a1f A	65	int (linkf)(const char , const char *);
6c780a1f A	66	char linkch;
44a7a5ab	67
6c780a1f A	68	int linkit(const char , const char , int);
6c780a1f A	69	void usage(void);
44a7a5ab A	70
44a7a5ab A	71	int
6c780a1f	72	main(int argc, char *argv[])
44a7a5ab A	73	{
44a7a5ab A	74	struct stat sb;
6c780a1f	75	char p, sourcedir;
44a7a5ab	76	int ch, exitval;
44a7a5ab	77
6c780a1f A	78	/*
	79	* Test for the special case where the utility is called as
	80	* "link", for which the functionality provided is greatly
	81	* simplified.
	82	*/
	83	if ((p = rindex(argv[0], '/')) == NULL)
	84	p = argv[0];
	85	else
	86	++p;
	87	if (strcmp(p, "link") == 0) {
	88	while (getopt(argc, argv, "") != -1)
	89	usage();
	90	argc -= optind;
	91	argv += optind;
	92	if (argc != 2)
	93	usage();
	94	linkf = link;
	95	exit(linkit(argv[0], argv[1], 0));
	96	}
	97
	98	while ((ch = getopt(argc, argv, "fhinsv")) != -1)
44a7a5ab A	99	switch (ch) {
	100	case 'f':
	101	fflag = 1;
6c780a1f	102	iflag = 0;
44a7a5ab A	103	break;
	104	case 'h':
	105	case 'n':
	106	hflag = 1;
	107	break;
6c780a1f A	108	case 'i':
	109	iflag = 1;
	110	fflag = 0;
	111	break;
44a7a5ab A	112	case 's':
	113	sflag = 1;
	114	break;
6c780a1f A	115	case 'v':
	116	vflag = 1;
	117	break;
44a7a5ab A	118	case '?':
	119	default:
	120	usage();
	121	}
	122
	123	argv += optind;
	124	argc -= optind;
	125
	126	linkf = sflag ? symlink : link;
6c780a1f	127	linkch = sflag ? '-' : '=';
44a7a5ab A	128
	129	switch(argc) {
	130	case 0:
	131	usage();
	132	/* NOTREACHED */
	133	case 1: /* ln target */
	134	exit(linkit(argv[0], ".", 1));
44a7a5ab A	135	case 2: /* ln target source */
44a7a5ab A	136	exit(linkit(argv[0], argv[1], 0));
6c780a1f A	137	default:
6c780a1f A	138	;
44a7a5ab A	139	}
	140	/* ln target1 target2 directory */
	141	sourcedir = argv[argc - 1];
	142	if (hflag && lstat(sourcedir, &sb) == 0 && S_ISLNK(sb.st_mode)) {
6c780a1f A	143	/*
	144	* We were asked not to follow symlinks, but found one at
	145	* the target--simulate "not a directory" error
	146	*/
44a7a5ab A	147	errno = ENOTDIR;
	148	err(1, "%s", sourcedir);
	149	}
	150	if (stat(sourcedir, &sb))
	151	err(1, "%s", sourcedir);
	152	if (!S_ISDIR(sb.st_mode))
	153	usage();
	154	for (exitval = 0; *argv != sourcedir; ++argv)
	155	exitval \|= linkit(*argv, sourcedir, 1);
	156	exit(exitval);
44a7a5ab A	157	}
	158
	159	int
6c780a1f	160	linkit(const char target, const char source, int isdir)
44a7a5ab A	161	{
44a7a5ab A	162	struct stat sb;
6c780a1f A	163	const char *p;
	164	int ch, exists, first;
	165	char path[PATH_MAX];
44a7a5ab A	166
	167	if (!sflag) {
	168	/* If target doesn't exist, quit now. */
	169	if (stat(target, &sb)) {
	170	warn("%s", target);
	171	return (1);
	172	}
6c780a1f A	173	/* Only symbolic links to directories. */
	174	if (S_ISDIR(sb.st_mode)) {
	175	errno = EISDIR;
	176	warn("%s", target);
	177	return (1);
	178	}
44a7a5ab A	179	}
44a7a5ab A	180
6c780a1f A	181	/*
	182	* If the source is a directory (and not a symlink if hflag),
	183	* append the target's name.
	184	*/
44a7a5ab	185	if (isdir \|\|
6c780a1f A	186	(lstat(source, &sb) == 0 && S_ISDIR(sb.st_mode)) \|\|
6c780a1f A	187	(!hflag && stat(source, &sb) == 0 && S_ISDIR(sb.st_mode))) {
44a7a5ab A	188	if ((p = strrchr(target, '/')) == NULL)
	189	p = target;
	190	else
	191	++p;
6c780a1f A	192	if (snprintf(path, sizeof(path), "%s/%s", source, p) >=
	193	(ssize_t)sizeof(path)) {
	194	errno = ENAMETOOLONG;
	195	warn("%s", target);
	196	return (1);
	197	}
44a7a5ab A	198	source = path;
	199	}
	200
6c780a1f	201	exists = !lstat(source, &sb);
44a7a5ab	202	/*
6c780a1f A	203	* If the file exists, then unlink it forcibly if -f was specified
6c780a1f A	204	* and interactively if -i was specified.
44a7a5ab	205	*/
6c780a1f A	206	if (fflag && exists) {
	207	if (unlink(source)) {
	208	warn("%s", source);
	209	return (1);
	210	}
	211	} else if (iflag && exists) {
	212	fflush(stdout);
	213	fprintf(stderr, "replace %s? ", source);
	214
	215	first = ch = getchar();
	216	while(ch != '\n' && ch != EOF)
	217	ch = getchar();
	218	if (first != 'y' && first != 'Y') {
	219	fprintf(stderr, "not replaced\n");
	220	return (1);
	221	}
	222
	223	if (unlink(source)) {
	224	warn("%s", source);
	225	return (1);
	226	}
	227	}
	228
	229	/* Attempt the link. */
	230	if ((*linkf)(target, source)) {
44a7a5ab A	231	warn("%s", source);
	232	return (1);
	233	}
6c780a1f A	234	if (vflag)
6c780a1f A	235	(void)printf("%s %c> %s\n", source, linkch, target);
44a7a5ab A	236	return (0);
	237	}
	238
	239	void
6c780a1f	240	usage(void)
44a7a5ab	241	{
6c780a1f A	242	(void)fprintf(stderr, "%s\n%s\n%s\n",
	243	"usage: ln [-fhinsv] file1 file2",
	244	" ln [-fhinsv] file ... directory",
	245	" link file1 file2");
44a7a5ab	246	exit(1);
44a7a5ab	247	}