/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/mount.h>
#include <sys/types.h>
#include <locale.h>
#include <sys/stat.h>
#include <fslib.h>
#include <stdio.h>
#include <sys/mnttab.h>
#include <poll.h>

#define MNTTYPE_TMPFS   "tmpfs"

static int      nmflg = 0;
static int      qflg = 0;

static boolean_t
in_mnttab(char *mountp)
{
        FILE *file;
        int found = B_FALSE;
        struct mnttab mntent;

        if ((file = fopen("/etc/mnttab", "r")) == NULL)
                return (B_FALSE);
        while (getmntent(file, &mntent) == 0) {
                if (mntent.mnt_mountp != NULL &&
                    strcmp(mntent.mnt_mountp, mountp) == 0 &&
                    mntent.mnt_fstype != NULL &&
                    strcmp(mntent.mnt_fstype, MNTTYPE_TMPFS) == 0) {
                        found = B_TRUE;
                        break;
                }
        }
        (void) fclose(file);
        return (found);
}

int
main(int argc, char *argv[])
{
        /* mount information */
        char *special;
        char *mountp;

        int c;
        char *myname;
        char typename[64];
        extern int optind;
        extern char *optarg;
        int error = 0;
        int verbose = 0;
        int mflg = 0;
        int optcnt = 0;
        int mount_attempts = 5;

        char optbuf[MAX_MNTOPT_STR];
        int optsize = 0;
        char *saveoptbuf;

        (void) setlocale(LC_ALL, "");

#if !defined(TEXT_DOMAIN)
#define TEXT_DOMAIN "SYS_TEST"
#endif
        (void) textdomain(TEXT_DOMAIN);

        myname = strrchr(argv[0], '/');
        myname = myname ? myname + 1 : argv[0];
        (void) snprintf(typename, sizeof (typename), "%s_%s",
            MNTTYPE_TMPFS, myname);
        argv[0] = typename;
        optbuf[0] = '\0';

        while ((c = getopt(argc, argv, "?o:VmOq")) != EOF) {
                switch (c) {
                case 'V':
                        verbose++;
                        break;
                case '?':
                        error++;
                        break;
                case 'm':
                        nmflg++;
                        break;
                case 'O':
                        mflg |= MS_OVERLAY;
                        break;
                case 'o':
                        (void) strncpy(optbuf, optarg, MAX_MNTOPT_STR);
                        optbuf[MAX_MNTOPT_STR - 1] = '\0';
                        optsize = strlen(optbuf);

                        if (verbose)
                                (void) fprintf(stderr, "optsize:%d optbuf:%s\n",
                                    optsize, optbuf);
                        break;
                case 'q':
                        qflg++;
                        break;
                }
        }

        if (verbose && !error) {
                char *optptr;

                (void) fprintf(stderr, "%s", typename);
                for (optcnt = 1; optcnt < argc; optcnt++) {
                        optptr = argv[optcnt];
                        if (optptr)
                                (void) fprintf(stderr, " %s", optptr);
                }
                (void) fprintf(stderr, "\n");
        }

        if (argc - optind != 2 || error) {
                (void) fprintf(stderr,
                    gettext("Usage: %s [-o size] swap mount_point\n"),
                    typename);
                exit(32);
        }

        special = argv[optind++];
        mountp = argv[optind++];
        mflg |= MS_OPTIONSTR;
        mflg |= (nmflg ? MS_NOMNTTAB : 0);

        if (verbose) {
                (void) fprintf(stderr, "mount(%s, \"%s\", %d, %s",
                    special, mountp, mflg, MNTTYPE_TMPFS);
                if (optsize)
                        (void) fprintf(stderr, ", \"%s\", %d)\n",
                            optbuf, strlen(optbuf));
                else
                        (void) fprintf(stderr, ")\n");
        }
        if (optsize) {
                if ((saveoptbuf = strdup(optbuf)) == NULL) {
                        (void) fprintf(stderr, gettext("%s: out of memory\n"),
                                "mount");
                        exit(1);
                }
        }
again:  if (mount(special, mountp, mflg, MNTTYPE_TMPFS, NULL, 0,
            optbuf, MAX_MNTOPT_STR)) {
                if (errno == EBUSY && !(mflg & MS_OVERLAY)) {
                        /*
                         * Because of bug 6176743, any attempt to mount
                         * tmpfs filesystem could fail for reasons
                         * described in that bug.  We're trying to detect
                         * that situation here by checking that the filesystem
                         * we're mounting is not in /etc/mnttab yet.
                         * When that bug is fixed, this code can be removed.
                         */
                        if (!in_mnttab(mountp) && mount_attempts-- > 0) {
                                (void) poll(NULL, 0, 50);
                                goto again;
                        }
                        (void) fprintf(stderr, gettext(
                            "%s: %s is already mounted or %s is busy\n"),
                            myname, mountp, special);
                } else {
                        perror("mount");
                }
                exit(32);
        }

        if (optsize && !qflg)
                cmp_requested_to_actual_options(saveoptbuf, optbuf,
                        special, mountp);
        return (0);
}