initial population

2 files changed, 685 insertions, 0 deletions

diff --git a/bin/ln/ln.1 b/bin/ln/ln.1
new file mode 100644
index 0000000..2eca74f
--- /dev/null
+++ b/bin/ln/ln.1
@@ -0,0 +1,320 @@
+.\" $NetBSD: ln.1,v 1.28 2017/04/20 22:57:30 christos Exp $
+.\"-
+.\" Copyright (c) 1980, 1990, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the Institute of Electrical and Electronics Engineers, Inc.
+.\"
+.\" 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. 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.
+.\"
+.\"	@(#)ln.1	8.2 (Berkeley) 12/30/93
+.\" $FreeBSD: head/bin/ln/ln.1 244791 2012-12-28 22:06:33Z gjb $
+.\"
+.Dd April 20, 2017
+.Dt LN 1
+.Os
+.Sh NAME
+.\" .Nm ln ,
+.\" .Nm link
+.Nm ln
+.Nd link files
+.Sh SYNOPSIS
+.Nm
+.Op Fl L | Fl P | Fl s Op Fl F
+.Op Fl f | iw
+.Op Fl hnv
+.Ar source_file
+.Op Ar target_file
+.Nm
+.Op Fl L | Fl P | Fl s Op Fl F
+.Op Fl f | iw
+.Op Fl hnv
+.Ar source_file ...
+.Ar target_dir
+.\" .Nm link
+.\" .Ar source_file Ar target_file
+.Sh DESCRIPTION
+The
+.Nm
+utility creates a new directory entry (linked file) for the file name
+specified by
+.Ar target_file .
+The
+.Ar target_file
+will be created with the same file modes as the
+.Ar source_file .
+It is useful for maintaining multiple copies of a file in many places
+at once without using up storage for the
+.Dq copies ;
+instead, a link
+.Dq points
+to the original copy.
+There are two types of links; hard links and symbolic links.
+How a link
+.Dq points
+to a file is one of the differences between a hard and symbolic link.
+.Pp
+The options are as follows:
+.Bl -tag -width flag
+.It Fl F
+If the target file already exists and is a directory, then remove it
+so that the link may occur.
+The
+.Fl F
+option should be used with either
+.Fl f
+or
+.Fl i
+options.
+If none is specified,
+.Fl f
+is implied.
+The
+.Fl F
+option is a no-op unless
+.Fl s
+option is specified.
+.It Fl L
+When creating a hard link to a symbolic link,
+create a hard link to the target of the symbolic link.
+This is the default.
+This option cancels the
+.Fl P
+option.
+.It Fl P
+When creating a hard link to a symbolic link,
+create a hard link to the symbolic link itself.
+This option cancels the
+.Fl L
+option.
+.It Fl f
+If the target file already exists,
+then unlink it so that the link may occur.
+(The
+.Fl f
+option overrides any previous
+.Fl i
+and
+.Fl w
+options.)
+.It Fl h
+If the
+.Ar target_file
+or
+.Ar target_dir
+is a symbolic link, do not follow it.
+This is most useful with the
+.Fl f
+option, to replace a symlink which may point to a directory.
+.It Fl i
+Cause
+.Nm
+to write a prompt to standard error if the target file exists.
+If the response from the standard input begins with the character
+.Sq Li y
+or
+.Sq Li Y ,
+then unlink the target file so that the link may occur.
+Otherwise, do not attempt the link.
+(The
+.Fl i
+option overrides any previous
+.Fl f
+options.)
+.It Fl n
+Same as
+.Fl h ,
+for compatibility with other
+.Nm
+implementations.
+.It Fl s
+Create a symbolic link.
+.It Fl v
+Cause
+.Nm
+to be verbose, showing files as they are processed.
+.It Fl w
+Warn if the source of a symbolic link does not currently exist.
+.El
+.Pp
+By default,
+.Nm
+makes
+.Em hard
+links.
+A hard link to a file is indistinguishable from the original directory entry;
+any changes to a file are effectively independent of the name used to reference
+the file.
+Directories may not be hardlinked, and hard links may not span file systems.
+.Pp
+A symbolic link contains the name of the file to
+which it is linked.
+The referenced file is used when an
+.Xr open 2
+operation is performed on the link.
+A
+.Xr stat 2
+on a symbolic link will return the linked-to file; an
+.Xr lstat 2
+must be done to obtain information about the link.
+The
+.Xr readlink 2
+call may be used to read the contents of a symbolic link.
+Symbolic links may span file systems and may refer to directories.
+.Pp
+Given one or two arguments,
+.Nm
+creates a link to an existing file
+.Ar source_file .
+If
+.Ar target_file
+is given, the link has that name;
+.Ar target_file
+may also be a directory in which to place the link;
+otherwise it is placed in the current directory.
+If only the directory is specified, the link will be made
+to the last component of
+.Ar source_file .
+.Pp
+Given more than two arguments,
+.Nm
+makes links in
+.Ar target_dir
+to all the named source files.
+The links made will have the same name as the files being linked to.
+.\" .Pp
+.\" When the utility is called as
+.\" .Nm link ,
+.\" exactly two arguments must be supplied,
+.\" neither of which may specify a directory.
+.\" No options may be supplied in this simple mode of operation,
+.\" which performs a
+.\" .Xr link 2
+.\" operation using the two passed arguments.
+.Sh EXAMPLES
+Create a symbolic link named
+.Pa /home/src
+and point it to
+.Pa /usr/src :
+.Pp
+.Dl # ln -s /usr/src /home/src
+.Pp
+Hard link
+.Pa /usr/local/bin/fooprog
+to file
+.Pa /usr/local/bin/fooprog-1.0 :
+.Pp
+.Dl # ln /usr/local/bin/fooprog-1.0 /usr/local/bin/fooprog
+.Pp
+As an exercise, try the following commands:
+.Bd -literal -offset indent
+# ls -i /bin/[
+11553 /bin/[
+# ls -i /bin/test
+11553 /bin/test
+.Ed
+.Pp
+Note that both files have the same inode; that is,
+.Pa /bin/[
+is essentially an alias for the
+.Xr test 1
+command.
+This hard link exists so
+.Xr test 1
+may be invoked from shell scripts, for example, using the
+.Li "if [ ]"
+construct.
+.Pp
+In the next example, the second call to
+.Nm
+removes the original
+.Pa foo
+and creates a replacement pointing to
+.Pa baz :
+.Bd -literal -offset indent
+# mkdir bar baz
+# ln -s bar foo
+# ln -shf baz foo
+.Ed
+.Pp
+Without the
+.Fl h
+option, this would instead leave
+.Pa foo
+pointing to
+.Pa bar
+and inside
+.Pa foo
+create a new symlink
+.Pa baz
+pointing to itself.
+This results from directory-walking.
+.Pp
+An easy rule to remember is that the argument order for
+.Nm
+is the same as for
+.Xr cp 1 :
+The first argument needs to exist, the second one is created.
+.Sh COMPATIBILITY
+The
+.Fl h ,
+.Fl i ,
+.Fl n ,
+.Fl v
+and
+.Fl w
+options are non-standard and their use in scripts is not recommended.
+They are provided solely for compatibility with other
+.Nm
+implementations.
+.Pp
+The
+.Fl F
+option is a
+.Fx
+extension and should not be used in portable scripts.
+.Sh SEE ALSO
+.Xr link 2 ,
+.Xr lstat 2 ,
+.Xr readlink 2 ,
+.Xr stat 2 ,
+.Xr symlink 2 ,
+.Xr symlink 7
+.Sh STANDARDS
+The
+.Nm
+utility conforms to
+.St -p1003.2-92 .
+.\" .Pp
+.\" The simplified
+.\" .Nm link
+.\" command conforms to
+.\" .St -susv2 .
+.Sh HISTORY
+An
+.Nm
+command appeared in
+.At v1 .
diff --git a/bin/ln/ln.c b/bin/ln/ln.c
new file mode 100644
index 0000000..b057e39
--- /dev/null
+++ b/bin/ln/ln.c
@@ -0,0 +1,365 @@
+/*	$NetBSD: ln.c,v 1.40 2018/08/26 23:01:06 sevan Exp $	*/
+
+/*-
+ * 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. 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>
+#ifdef __FBSDID
+__FBSDID("$FreeBSD: head/bin/ln/ln.c 251261 2013-06-02 17:55:00Z eadler $");
+#endif
+__RCSID("$NetBSD: ln.c,v 1.40 2018/08/26 23:01:06 sevan Exp $");
+
+#include <sys/param.h>
+#include <sys/stat.h>
+
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+static int	fflag;			/* Unlink existing files. */
+static int	Fflag;			/* Remove empty directories also. */
+static int	hflag;			/* Check new name for symlink first. */
+static int	iflag;			/* Interactive mode. */
+static int	Pflag;			/* Create hard links to symlinks. */
+static int	sflag;			/* Symbolic, not hard, link. */
+static int	vflag;			/* Verbose output. */
+static int	wflag;			/* Warn if symlink target does not
+					 * exist, and -f is not enabled. */
+static char	linkch;
+
+static int	linkit(const char *, const char *, int);
+static __dead void	usage(void);
+
+int
+main(int argc, char *argv[])
+{
+	struct stat sb;
+	char *p, *targetdir;
+	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 = strrchr(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();
+		if (link(argv[0], argv[1]) == -1)
+			err(EXIT_FAILURE, NULL);
+		exit(EXIT_SUCCESS);
+	}
+
+	while ((ch = getopt(argc, argv, "FLPfhinsvw")) != -1)
+		switch (ch) {
+		case 'F':
+			Fflag = 1;
+			break;
+		case 'L':
+			Pflag = 0;
+			break;
+		case 'P':
+			Pflag = 1;
+			break;
+		case 'f':
+			fflag = 1;
+			iflag = 0;
+			wflag = 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 'w':
+			wflag = 1;
+			break;
+		case '?':
+		default:
+			usage();
+		}
+
+	argv += optind;
+	argc -= optind;
+
+	linkch = sflag ? '-' : '=';
+	if (sflag == 0)
+		Fflag = 0;
+	if (Fflag == 1 && iflag == 0) {
+		fflag = 1;
+		wflag = 0;		/* Implied when fflag != 0 */
+	}
+
+	switch(argc) {
+	case 0:
+		usage();
+		/* NOTREACHED */
+	case 1:				/* ln source */
+		exit(linkit(argv[0], ".", 1));
+	case 2:				/* ln source target */
+		exit(linkit(argv[0], argv[1], 0));
+	default:
+		;
+	}
+					/* ln source1 source2 directory */
+	targetdir = argv[argc - 1];
+	if (hflag && lstat(targetdir, &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", targetdir);
+	}
+	if (stat(targetdir, &sb))
+		err(1, "%s", targetdir);
+	if (!S_ISDIR(sb.st_mode))
+		usage();
+	for (exitval = 0; *argv != targetdir; ++argv)
+		exitval |= linkit(*argv, targetdir, 1);
+	exit(exitval);
+}
+
+/*
+ * Two pathnames refer to the same directory entry if the directories match
+ * and the final components' names match.
+ */
+static int
+samedirent(const char *path1, const char *path2)
+{
+	const char *file1, *file2;
+	char pathbuf[PATH_MAX];
+	struct stat sb1, sb2;
+
+	if (strcmp(path1, path2) == 0)
+		return 1;
+	file1 = strrchr(path1, '/');
+	if (file1 != NULL)
+		file1++;
+	else
+		file1 = path1;
+	file2 = strrchr(path2, '/');
+	if (file2 != NULL)
+		file2++;
+	else
+		file2 = path2;
+	if (strcmp(file1, file2) != 0)
+		return 0;
+	if (file1 - path1 >= PATH_MAX || file2 - path2 >= PATH_MAX)
+		return 0;
+	if (file1 == path1)
+		memcpy(pathbuf, ".", 2);
+	else {
+		memcpy(pathbuf, path1, file1 - path1);
+		pathbuf[file1 - path1] = '\0';
+	}
+	if (stat(pathbuf, &sb1) != 0)
+		return 0;
+	if (file2 == path2)
+		memcpy(pathbuf, ".", 2);
+	else {
+		memcpy(pathbuf, path2, file2 - path2);
+		pathbuf[file2 - path2] = '\0';
+	}
+	if (stat(pathbuf, &sb2) != 0)
+		return 0;
+	return sb1.st_dev == sb2.st_dev && sb1.st_ino == sb2.st_ino;
+}
+
+static int
+linkit(const char *source, const char *target, int isdir)
+{
+	struct stat sb;
+	const char *p;
+	int ch, exists, first;
+	char path[PATH_MAX];
+	char wbuf[PATH_MAX];
+	char bbuf[PATH_MAX];
+
+	if (!sflag) {
+		/* If source doesn't exist, quit now. */
+		if ((Pflag ? lstat : stat)(source, &sb)) {
+			warn("%s", source);
+			return (1);
+		}
+		/* Only symbolic links to directories. */
+		if (S_ISDIR(sb.st_mode)) {
+			errno = EISDIR;
+			warn("%s", source);
+			return (1);
+		}
+	}
+
+	/*
+	 * If the target is a directory (and not a symlink if hflag),
+	 * append the source's name.
+	 */
+	if (isdir ||
+	    (lstat(target, &sb) == 0 && S_ISDIR(sb.st_mode)) ||
+	    (!hflag && stat(target, &sb) == 0 && S_ISDIR(sb.st_mode))) {
+		if (strlcpy(bbuf, source, sizeof(bbuf)) >= sizeof(bbuf) ||
+		    (p = basename(bbuf)) == NULL ||
+		    snprintf(path, sizeof(path), "%s/%s", target, p) >=
+		    (ssize_t)sizeof(path)) {
+			errno = ENAMETOOLONG;
+			warn("%s", source);
+			return (1);
+		}
+		target = path;
+	}
+
+	/*
+	 * If the link source doesn't exist, and a symbolic link was
+	 * requested, and -w was specified, give a warning.
+	 */
+	if (sflag && wflag) {
+		if (*source == '/') {
+			/* Absolute link source. */
+			if (stat(source, &sb) != 0)
+				 warn("warning: %s inaccessible", source);
+		} else {
+			/*
+			 * Relative symlink source.  Try to construct the
+			 * absolute path of the source, by appending `source'
+			 * to the parent directory of the target.
+			 */
+			strlcpy(bbuf, target, sizeof(bbuf));
+			p = dirname(bbuf);
+			if (p != NULL) {
+				(void)snprintf(wbuf, sizeof(wbuf), "%s/%s",
+						p, source);
+				if (stat(wbuf, &sb) != 0)
+					warn("warning: %s", source);
+			}
+		}
+	}
+
+	/*
+	 * If the file exists, first check it is not the same directory entry.
+	 */
+	exists = !lstat(target, &sb);
+	if (exists) {
+		if (!sflag && samedirent(source, target)) {
+			warnx("%s and %s are the same directory entry",
+			    source, target);
+			return (1);
+		}
+	}
+	/*
+	 * 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(target)) {
+				warn("%s", target);
+				return (1);
+			}
+		} else if (unlink(target)) {
+			warn("%s", target);
+			return (1);
+		}
+	} else if (iflag && exists) {
+		fflush(stdout);
+		fprintf(stderr, "replace %s? ", target);
+
+		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(target)) {
+				warn("%s", target);
+				return (1);
+			}
+		} else if (unlink(target)) {
+			warn("%s", target);
+			return (1);
+		}
+	}
+
+	/* Attempt the link. */
+	if (sflag ? symlink(source, target) :
+	    linkat(AT_FDCWD, source, AT_FDCWD, target,
+	    Pflag ? 0 : AT_SYMLINK_FOLLOW)) {
+		warn("%s", target);
+		return (1);
+	}
+	if (vflag)
+		(void)printf("%s %c> %s\n", target, linkch, source);
+	return (0);
+}
+
+static __dead void
+usage(void)
+{
+	(void)fprintf(stderr, 
+	    "usage: %s [-L | -P | -s [-F]] [-f | -iw] [-hnv] source_file [target_file]\n"
+	    "       %s [-L | -P | -s [-F]] [-f | -iw] [-hnv] source_file ... target_dir\n"
+	    "       link source_file target_file\n", getprogname(), getprogname());
+	exit(1);
+}