source: kBuild/trunk/src/kmk/kmkbuiltin/ln.c@ 2060

/*-
 * 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 */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/bin/ln/ln.c,v 1.33 2005/02/09 17:37:37 ru Exp $");
#endif /* no $id */

#ifndef _MSC_VER
# include <sys/param.h>
#endif
#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>
#include "getopt.h"
#ifdef _MSC_VER
# include "mscfakes.h"
#endif
#include "kmkbuiltin.h"

static int      fflag;                          /* Unlink existing files. */
static int      hflag;                          /* Check new name for symlink first. */
static int      iflag;                          /* Interactive mode. */
static int      sflag;                          /* Symbolic, not hard, link. */
static int      vflag;                          /* Verbose output. */
                                        /* System link call. */
static int (*linkf)(const char *, const char *);
static char     linkch;
static struct option long_options[] =
{
    { "help",                                           no_argument, 0, 261 },
    { "version",                                        no_argument, 0, 262 },
    { 0, 0,     0, 0 },
};


static int      linkit(const char *, const char *, int);
static int      usage(FILE *);


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

        /* initialize globals. */
        fflag = hflag = iflag = sflag = vflag = 0;
        linkch = 0;
        linkf = NULL;

        /* kmk: reset getopt() and set program name. */
        g_progname = argv[0];
        opterr = 1;
        optarg = NULL;
        optopt = 0;
        optind = 0; /* init */

        while ((ch = getopt_long(argc, argv, "fhinsv", long_options, NULL)) != -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 261:
                        usage(stdout);
                        return 0;
                case 262:
                        return kbuild_version(argv[0]);
                case '?':
                default:
                        return usage(stderr);
                }

        argv += optind;
        argc -= optind;

        linkf = sflag ? symlink : link;
        linkch = sflag ? '-' : '=';

        switch(argc) {
        case 0:
                return usage(stderr);
                /* NOTREACHED */
        case 1:                         /* ln target */
                return linkit(argv[0], ".", 1);
        case 2:                         /* ln target source */
                return 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;
                return err(1, "%s", sourcedir);
        }
        if (stat(sourcedir, &sb))
                return err(1, "%s", sourcedir);
        if (!S_ISDIR(sb.st_mode))
                return usage(stderr);
        for (exitval = 0; *argv != sourcedir; ++argv)
                exitval |= linkit(*argv, sourcedir, 1);
        return exitval;
}

static 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))) {
#ifdef _MSC_VER || defined(__OS2__)
                char *p2 = strrchr(target, '\\');
                p = strrchr(target, '/');
                if (p2 != NULL && (p == NULL || p2 > p))
                        p = p2;
                if (p == NULL)
#else
                if ((p = strrchr(target, '/')) == NULL)
#endif
                        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);
}

static int
usage(FILE *pf)
{
        fprintf(pf, "usage: %s [-fhinsv] source_file [target_file]\n"
                                "   or: %s [-fhinsv] source_file ... target_dir\n"
                "   or: %s source_file target_file\n"
                                "   or: %s --help\n"
                                "   or: %s --version\n",
                g_progname, g_progname, g_progname, g_progname, g_progname);
        return 1;
}