/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 1994, 1995, 1996, 1998 Peter Wemm <peter@netplex.com.au>
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 */

/*
 * This program was originally written long ago, originally for a non
 * BSD-like OS without mkstemp().  It's been modified over the years
 * to use mkstemp() rather than the original O_CREAT|O_EXCL/fstat/lstat
 * etc style hacks.
 * A cleanup, misc options and mkdtemp() calls were added to try and work
 * more like the OpenBSD version - which was first to publish the interface.
 */

#include <err.h>
#include <getopt.h>
#include <paths.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static void usage(void) __dead2;

static const struct option long_opts[] = {
        {"directory",   no_argument,    NULL,   'd'},
        {"tmpdir",      optional_argument,      NULL,   'p'},
        {"quiet",       no_argument,    NULL,   'q'},
        {"dry-run",     no_argument,    NULL,   'u'},
        {NULL,          no_argument,    NULL,   0},
};

int
main(int argc, char **argv)
{
        int c, fd, ret;
        const char *prefix, *tmpdir;
        char *name;
        int dflag, qflag, tflag, uflag;
        bool prefer_tmpdir;

        ret = dflag = qflag = tflag = uflag = 0;
        prefer_tmpdir = true;
        prefix = "mktemp";
        name = NULL;
        tmpdir = NULL;

        while ((c = getopt_long(argc, argv, "dp:qt:u", long_opts, NULL)) != -1)
                switch (c) {
                case 'd':
                        dflag++;
                        break;

                case 'p':
                        tmpdir = optarg;
                        if (tmpdir == NULL || *tmpdir == '\0')
                                tmpdir = getenv("TMPDIR");

                        /*
                         * We've already done the necessary environment
                         * fallback, skip the later one.
                         */
                        prefer_tmpdir = false;
                        break;

                case 'q':
                        qflag++;
                        break;

                case 't':
                        prefix = optarg;
                        tflag++;
                        break;

                case 'u':
                        uflag++;
                        break;

                default:
                        usage();
                }

        argc -= optind;
        argv += optind;

        if (!tflag && argc < 1) {
                tflag = 1;
                prefix = "tmp";

                /*
                 * For this implied -t mode, we actually want to swap the usual
                 * order of precedence: -p, then TMPDIR, then /tmp.
                 */
                prefer_tmpdir = false;
        }

        if (tflag) {
                const char *envtmp;
                size_t len;

                envtmp = NULL;

                /*
                 * $TMPDIR preferred over `-p` if specified, for compatibility.
                 */
                if (prefer_tmpdir || tmpdir == NULL)
                        envtmp = getenv("TMPDIR");
                if (envtmp != NULL)
                        tmpdir = envtmp;
                if (tmpdir == NULL)
                        tmpdir = _PATH_TMP;
                len = strlen(tmpdir);
                if (len > 0 && tmpdir[len - 1] == '/')
                        asprintf(&name, "%s%s.XXXXXXXXXX", tmpdir, prefix);
                else
                        asprintf(&name, "%s/%s.XXXXXXXXXX", tmpdir, prefix);
                /* if this fails, the program is in big trouble already */
                if (name == NULL) {
                        if (qflag)
                                return (1);
                        else
                                errx(1, "cannot generate template");
                }
        }

        /* generate all requested files */
        while (name != NULL || argc > 0) {
                if (name == NULL) {
                        if (!tflag && tmpdir != NULL)
                                asprintf(&name, "%s/%s", tmpdir, argv[0]);
                        else
                                name = strdup(argv[0]);
                        if (name == NULL)
                                err(1, "%s", argv[0]);
                        argv++;
                        argc--;
                }

                if (dflag) {
                        if (mkdtemp(name) == NULL) {
                                ret = 1;
                                if (!qflag)
                                        warn("mkdtemp failed on %s", name);
                        } else {
                                printf("%s\n", name);
                                if (uflag)
                                        rmdir(name);
                        }
                } else {
                        fd = mkstemp(name);
                        if (fd < 0) {
                                ret = 1;
                                if (!qflag)
                                        warn("mkstemp failed on %s", name);
                        } else {
                                close(fd);
                                if (uflag)
                                        unlink(name);
                                printf("%s\n", name);
                        }
                }
                if (name)
                        free(name);
                name = NULL;
        }
        return (ret);
}

static void
usage(void)
{
        fprintf(stderr,
                "usage: mktemp [-d] [-p tmpdir] [-q] [-t prefix] [-u] template "
                "...\n");
        fprintf(stderr,
                "       mktemp [-d] [-p tmpdir] [-q] [-u] -t prefix \n");
        exit (1);
}