/*
 * Copyright (c) 2003,2004 The DragonFly Project.  All rights reserved.
 * 
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@backplane.com>
 * 
 * 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 DragonFly Project 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 COPYRIGHT HOLDERS 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
 * COPYRIGHT HOLDERS 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.
 * 
 * $DragonFly: src/sbin/mountctl/mountctl.c,v 1.10 2008/02/05 20:49:50 dillon Exp $
 */
/*
 * This utility implements the userland mountctl command which is used to
 * manage high level journaling on mount points.
 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/ucred.h>
#include <sys/mount.h>
#include <sys/time.h>
#include <sys/mountctl.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

static void usage(void);
static void parse_option_keyword(const char *opt, 
                const char **wopt, const char **xopt);
static int64_t getsize(const char *str);
static const char *numtostr(int64_t num);

static int mountctl_scan(void (*func)(const char *, const char *, int, void *),
                const char *keyword, const char *mountpt, int fd);
static void mountctl_list(const char *keyword, const char *mountpt,
                int __unused fd, void *info);
static void mountctl_add(const char *keyword, const char *mountpt, int fd);
static void mountctl_restart(const char *keyword, const char *mountpt, 
                int fd, void __unused *);
static void mountctl_delete(const char *keyword, const char *mountpt,
                int __unused fd, void __unused *);
static void mountctl_modify(const char *keyword, const char *mountpt, int fd, void __unused *);

/*
 * For all options 0 means unspecified, -1 means noOPT or nonOPT, and a
 * positive number indicates enabling or execution of the option.
 */
static int exitCode;
static int freeze_opt;
static int start_opt;
static int close_opt;
static int abort_opt;
static int flush_opt;
static int reversable_opt;
static int twoway_opt;
static int output_safety_override_opt;
static int64_t memfifo_opt;
static int64_t swapfifo_opt;

int
main(int ac, char **av)
{
    int fd;
    int ch;
    int aopt = 0;
    int dopt = 0;
    int fopt = 0;
    int lopt = 0;
    int mopt = 0;
    int ropt = 0;
    int mimplied = 0;
    const char *wopt = NULL;
    const char *xopt = NULL;
    const char *keyword = NULL;
    const char *mountpt = NULL;
    char *tmp;

    while ((ch = getopt(ac, av, "2adflmo:rw:x:ACFSW:X:Z")) != -1) {
        switch(ch) {
        case '2':
            twoway_opt = 1;
            break;
        case 'r':
            ropt = 1;
            if (aopt + dopt + lopt + mopt + ropt != 1) {
                fprintf(stderr, "too many action options specified\n");
                usage();
            }
            break;
        case 'a':
            aopt = 1;
            if (aopt + dopt + lopt + mopt + ropt != 1) {
                fprintf(stderr, "too many action options specified\n");
                usage();
            }
            break;
        case 'd':
            dopt = 1;
            if (aopt + dopt + lopt + mopt + ropt != 1) {
                fprintf(stderr, "too many action options specified\n");
                usage();
            }
            break;
        case 'f':
            fopt = 1;
            break;
        case 'l':
            lopt = 1;
            if (aopt + dopt + lopt + mopt + ropt != 1) {
                fprintf(stderr, "too many action options specified\n");
                usage();
            }
            break;
        case 'o':
            parse_option_keyword(optarg, &wopt, &xopt);
            break;
        case 'm':
            mopt = 1;
            if (aopt + dopt + lopt + mopt + ropt != 1) {
                fprintf(stderr, "too many action options specified\n");
                usage();
            }
            break;
        case 'W':
            output_safety_override_opt = 1;
            /* fall through */
        case 'w':
            wopt = optarg;
            mimplied = 1;
            break;
        case 'X':
            output_safety_override_opt = 1;
            /* fall through */
        case 'x':
            xopt = optarg;
            mimplied = 1;
            break;
        case 'A':
            mimplied = 1;
            abort_opt = 1;
            break;
        case 'C':
            mimplied = 1;
            close_opt = 1;
            break;
        case 'F':
            mimplied = 1;
            flush_opt = 1;
            break;
        case 'S':
            mimplied = 1;
            start_opt = 1;
            break;
        case 'Z':
            mimplied = 1;
            freeze_opt = 1;
            break;
        default:
            fprintf(stderr, "unknown option: -%c\n", optopt);
            usage();
        }
    }
    ac -= optind;
    av += optind;

    /*
     * Parse the keyword and/or mount point.
     */
    switch(ac) {
    case 0:
        if (aopt || ropt) {
            fprintf(stderr, "action requires a tag and/or mount "
                            "point to be specified\n");
            usage();
        }
        break;
    case 1:
        if (av[0][0] == '/') {
            mountpt = av[0];
            if ((keyword = strchr(mountpt, ':')) != NULL) {
                ++keyword;
                tmp = strdup(mountpt);
                *strchr(tmp, ':') = 0;
                mountpt = tmp;
            }
        } else {
            keyword = av[0];
        }
        break;
    default:
        fprintf(stderr, "unexpected extra arguments to command\n");
        usage();
    }

    /*
     * Additional sanity checks
     */
    if (aopt + dopt + lopt + mopt + ropt + mimplied == 0) {
        fprintf(stderr, "no action or implied action options were specified\n");
        usage();
    }
    if (mimplied && aopt + dopt + lopt + ropt == 0)
        mopt = 1;
    if ((wopt || xopt) && !(aopt || ropt || mopt)) {
        fprintf(stderr, "-w/-x/path/fd options may only be used with -m/-a/-r\n");
        usage();
    }
    if (aopt && (keyword == NULL || mountpt == NULL)) {
        fprintf(stderr, "a keyword AND a mountpt must be specified "
                        "when adding a journal\n");
        usage();
    }
    if (fopt == 0 && mopt + dopt && keyword == NULL && mountpt == NULL) {
        fprintf(stderr, "a keyword, a mountpt, or both must be specified "
                        "when modifying or deleting a journal, unless "
                        "-f is also specified for safety\n");
        usage();
    }

    /*
     * Open the journaling file descriptor if required.
     */
    if (wopt && xopt) {
        fprintf(stderr, "you must specify only one of -w/-x/path/fd\n");
        exit(1);
    } else if (wopt) {
        if ((fd = open(wopt, O_RDWR|O_CREAT|O_APPEND, 0666)) < 0) {
            fprintf(stderr, "unable to create %s: %s\n", wopt, strerror(errno));
            exit(1);
        }
    } else if (xopt) {
        fd = strtol(xopt, NULL, 0);
    } else if (aopt || ropt) {
        fd = 1;         /* stdout default for -a */
    } else {
        fd = -1;
    }

    /*
     * And finally execute the core command.
     */
    if (lopt)
        mountctl_scan(mountctl_list, keyword, mountpt, fd);
    if (aopt)
        mountctl_add(keyword, mountpt, fd);
    if (ropt) {
        ch = mountctl_scan(mountctl_restart, keyword, mountpt, fd);
        if (ch)
            fprintf(stderr, "%d journals restarted\n", ch);
        else
            fprintf(stderr, "Unable to locate any matching journals\n");
    }
    if (dopt) {
        ch = mountctl_scan(mountctl_delete, keyword, mountpt, -1);
        if (ch)
            fprintf(stderr, "%d journals deleted\n", ch);
        else
            fprintf(stderr, "Unable to locate any matching journals\n");
    }
    if (mopt) {
        ch = mountctl_scan(mountctl_modify, keyword, mountpt, fd);
        if (ch)
            fprintf(stderr, "%d journals modified\n", ch);
        else
            fprintf(stderr, "Unable to locate any matching journals\n");
    }

    return(exitCode);
}

static void
parse_option_keyword(const char *opt, const char **wopt, const char **xopt)
{
    char *str = strdup(opt);
    char *name;
    char *val;
    int negate;
    int hasval;
    int cannotnegate;

    /*
     * multiple comma delimited options may be specified.
     */
    while ((name = strsep(&str, ",")) != NULL) {
        /*
         * some options have associated data.
         */
        if ((val = strchr(name, '=')) != NULL)
            *val++ = 0;

        /*
         * options beginning with 'no' or 'non' are negated.  A positive
         * number means not negated, a negative number means negated.
         */
        negate = 1;
        cannotnegate = 0;
        hasval = 0;
        if (strncmp(name, "non", 3) == 0) {
            name += 3;
            negate = -1;
        } else if (strncmp(name, "no", 2) == 0) {
            name += 2;
            negate = -1;
        }

        /*
         * Parse supported options
         */
        if (strcmp(name, "undo") == 0) {
            reversable_opt = negate;
        } else if (strcmp(name, "reversable") == 0) {
            reversable_opt = negate;
        } else if (strcmp(name, "twoway") == 0) {
            twoway_opt = negate;
        } else if (strcmp(name, "memfifo") == 0) {
            cannotnegate = 1;
            hasval = 1;
            if (val) {
                if ((memfifo_opt = getsize(val)) == 0)
                    memfifo_opt = -1;
            }
        } else if (strcmp(name, "swapfifo") == 0) {
            if (val) {
                hasval = 1;
                if ((swapfifo_opt = getsize(val)) == 0)
                    swapfifo_opt = -1;
            } else if (negate < 0) {
                swapfifo_opt = -1;
            } else {
                hasval = 1;     /* force error */
            }
        } else if (strcmp(name, "fd") == 0) {
            cannotnegate = 1;
            hasval = 1;
            if (val)
                *xopt = val;
        } else if (strcmp(name, "path") == 0) {
            cannotnegate = 1;
            hasval = 1;
            if (val)
                *wopt = val;
        } else if (strcmp(name, "freeze") == 0 || strcmp(name, "stop") == 0) {
            if (negate < 0)
                start_opt = -negate;
            else
                freeze_opt = negate;
        } else if (strcmp(name, "start") == 0) {
            if (negate < 0)
                freeze_opt = -negate;
            else
                start_opt = negate;
        } else if (strcmp(name, "close") == 0) {
            close_opt = negate;
        } else if (strcmp(name, "abort") == 0) {
            abort_opt = negate;
        } else if (strcmp(name, "flush") == 0) {
            flush_opt = negate;
        } else {
            fprintf(stderr, "unknown option keyword: %s\n", name);
            exit(1);
        }

        /*
         * Sanity checks
         */
        if (cannotnegate && negate < 0) {
            fprintf(stderr, "option %s may not be negated\n", name);
            exit(1);
        }
        if (hasval && val == NULL) {
            fprintf(stderr, "option %s requires assigned data\n", name);
            exit(1);
        }
        if (hasval == 0 && val) {
            fprintf(stderr, "option %s does not take an assignment\n", name);
            exit(1);
        }

    }
}

static int
mountctl_scan(void (*func)(const char *, const char *, int, void *),
            const char *keyword, const char *mountpt, int fd)
{
    struct statfs *sfs;
    int count;
    int calls;
    int i;
    struct mountctl_status_journal statreq;
    struct mountctl_journal_ret_status rstat[4];        /* BIG */

    calls = 0;
    if (mountpt) {
        bzero(&statreq, sizeof(statreq));
        if (keyword) {
            statreq.index = MC_JOURNAL_INDEX_ID;
            count = strlen(keyword);
            if (count > JIDMAX)
                count = JIDMAX;
            bcopy(keyword, statreq.id, count);
        } else {
            statreq.index = MC_JOURNAL_INDEX_ALL;
        }
        count = mountctl(mountpt, MOUNTCTL_STATUS_VFS_JOURNAL, -1,
                        &statreq, sizeof(statreq), &rstat, sizeof(rstat));
        if (count > 0 && rstat[0].recsize != sizeof(rstat[0])) {
            fprintf(stderr, "Unable to access status, "
                            "structure size mismatch\n");
            exit(1);
        }
        if (count > 0) {
            count /= sizeof(rstat[0]);
            for (i = 0; i < count; ++i) {
                func(rstat[i].id, mountpt, fd, &rstat[i]);
                ++calls;
            }
        }
    } else {
        if ((count = getmntinfo(&sfs, MNT_WAIT)) > 0) {
            for (i = 0; i < count; ++i) {
                calls += mountctl_scan(func, keyword, sfs[i].f_mntonname, fd);
            }
        } else if (count < 0) {
            /* XXX */
        }
    }
    return(calls);
}

static void
mountctl_list(const char *keyword __unused, const char *mountpt,
              int fd __unused, void *info)
{
    struct mountctl_journal_ret_status *rstat = info;

    printf("%s:%s\n", mountpt, rstat->id[0] ? rstat->id : "<NOID>");
    printf("    membufsize=%s\n", numtostr(rstat->membufsize));
    printf("    membufused=%s\n", numtostr(rstat->membufused));
    printf("    membufunacked=%s\n", numtostr(rstat->membufunacked));
    printf("    total_bytes=%s\n", numtostr(rstat->bytessent));
    printf("    fifo_stalls=%jd\n", (intmax_t)rstat->fifostalls);
}

static void
mountctl_add(const char *keyword, const char *mountpt, int fd)
{
    struct mountctl_install_journal joinfo;
    struct stat st1;
    struct stat st2;
    int error;

    /*
     * Make sure the file descriptor is not on the same filesystem as the
     * mount point.  This isn't a perfect test, but it should catch most
     * foot shooting.
     */
    if (output_safety_override_opt == 0 &&
        fstat(fd, &st1) == 0 && S_ISREG(st1.st_mode) &&
        stat(mountpt, &st2) == 0 && st1.st_dev == st2.st_dev
    ) {
        fprintf(stderr, "%s:%s failed to add, the journal cannot be on the "
                        "same filesystem being journaled!\n",
                        mountpt, keyword);
        exitCode = 1;
        return;
    }

    /*
     * Setup joinfo and issue the add
     */
    bzero(&joinfo, sizeof(joinfo));
    snprintf(joinfo.id, sizeof(joinfo.id), "%s", keyword);
    if (memfifo_opt > 0)
        joinfo.membufsize = memfifo_opt;
    if (twoway_opt > 0)
        joinfo.flags |= MC_JOURNAL_WANT_FULLDUPLEX;
    if (reversable_opt > 0)
        joinfo.flags |= MC_JOURNAL_WANT_REVERSABLE;

    error = mountctl(mountpt, MOUNTCTL_INSTALL_VFS_JOURNAL, fd,
                        &joinfo, sizeof(joinfo), NULL, 0);
    if (error == 0) {
        fprintf(stderr, "%s:%s added\n", mountpt, joinfo.id);
    } else {
        fprintf(stderr, "%s:%s failed to add, error %s\n", mountpt, joinfo.id, strerror(errno));
        exitCode = 1;
    }
}

static void
mountctl_restart(const char *keyword, const char *mountpt, 
                 int fd, void __unused *info)
{
    struct mountctl_restart_journal joinfo;
    int error;

    /* XXX make sure descriptor is not on same filesystem as journal */

    bzero(&joinfo, sizeof(joinfo));

    snprintf(joinfo.id, sizeof(joinfo.id), "%s", keyword);
    if (twoway_opt > 0)
        joinfo.flags |= MC_JOURNAL_WANT_FULLDUPLEX;
    if (reversable_opt > 0)
        joinfo.flags |= MC_JOURNAL_WANT_REVERSABLE;

    error = mountctl(mountpt, MOUNTCTL_RESTART_VFS_JOURNAL, fd,
                        &joinfo, sizeof(joinfo), NULL, 0);
    if (error == 0) {
        fprintf(stderr, "%s:%s restarted\n", mountpt, joinfo.id);
    } else {
        fprintf(stderr, "%s:%s restart failed, error %s\n", mountpt, joinfo.id, strerror(errno));
    }
}

static void
mountctl_delete(const char *keyword, const char *mountpt, 
                int __unused fd, void __unused *info)
{
    struct mountctl_remove_journal joinfo;
    int error;

    bzero(&joinfo, sizeof(joinfo));
    snprintf(joinfo.id, sizeof(joinfo.id), "%s", keyword);
    error = mountctl(mountpt, MOUNTCTL_REMOVE_VFS_JOURNAL, -1,
                        &joinfo, sizeof(joinfo), NULL, 0);
    if (error == 0) {
        fprintf(stderr, "%s:%s deleted\n", mountpt, joinfo.id);
    } else {
        fprintf(stderr, "%s:%s deletion failed, error %s\n", mountpt, joinfo.id, strerror(errno));
    }
}

static void
mountctl_modify(const char *keyword __unused, const char *mountpt __unused,
                int fd __unused, void *info __unused)
{
    fprintf(stderr, "modify not yet implemented\n");
}


static void
usage(void)
{
    printf(
        "usage: mountctl -l {mountpt | tag | mountpt:tag}\n"
        "       mountctl -a [-2] [-w/W output_path] [-x/X filedesc]\n"
        "                   [-o options] mountpt:tag\n"
        "       mountctl -r [-2] [-w/W output_path] [-x/X filedesc] mountpt:tag\n"
        "       mountctl -d {mountpt | tag | mountpt:tag}\n"
        "       mountctl -m [-o options] {mountpt | tag | mountpt:tag}\n"
        "       mountctl -FZSCA {mountpt | tag | mountpt:tag}\n"
    );
    exit(1);
}

static int64_t
getsize(const char *str)
{
    char *suffix;
    int64_t val;

    val = strtoll(str, &suffix, 0);
    if (suffix) {
        switch(*suffix) {
        case 'b':
            break;
        case 't':
            val *= 1024;
            /* fall through */
        case 'g':
            val *= 1024;
            /* fall through */
        case 'm':
            val *= 1024;
            /* fall through */
        case 'k':
            val *= 1024;
            /* fall through */
            break;
        default:
            fprintf(stderr, "data value '%s' has unknown suffix\n", str);
            exit(1);
        }
    }
    return(val);
}

static const char *
numtostr(int64_t num)
{
    static char buf[64];

    if (num < 1024)
        snprintf(buf, sizeof(buf), "%jd", (intmax_t)num);
    else if (num < 10 * 1024)
        snprintf(buf, sizeof(buf), "%3.2fK", num / 1024.0);
    else if (num < 1024 * 1024)
        snprintf(buf, sizeof(buf), "%3.0fK", num / 1024.0);
    else if (num < 10 * 1024 * 1024)
        snprintf(buf, sizeof(buf), "%3.2fM", num / (1024.0 * 1024.0));
    else if (num < 1024 * 1024 * 1024)
        snprintf(buf, sizeof(buf), "%3.0fM", num / (1024.0 * 1024.0));
    else if (num < 10LL * 1024 * 1024 * 1024)
        snprintf(buf, sizeof(buf), "%3.2fG", num / (1024.0 * 1024.0 * 1024.0));
    else
        snprintf(buf, sizeof(buf), "%3.0fG", num / (1024.0 * 1024.0 * 1024.0));
    return(buf);
}