Fix memory leak in recv_skip

[mirror_zfs.git] / lib / libzfs / libzfs_util.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
 * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
 */

/*
 * Internal utility routines for the ZFS library.
 */

#include <errno.h>
#include <fcntl.h>
#include <libintl.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <unistd.h>
#include <ctype.h>
#include <math.h>
#include <sys/stat.h>
#include <sys/mnttab.h>
#include <sys/mntent.h>
#include <sys/types.h>
#include <wait.h>

#include <libzfs.h>
#include <libzfs_core.h>

#include "libzfs_impl.h"
#include "zfs_prop.h"
#include "zfeature_common.h"
#include <zfs_fletcher.h>

int
libzfs_errno(libzfs_handle_t *hdl)
{
        return (hdl->libzfs_error);
}

const char *
libzfs_error_init(int error)
{
        switch (error) {
        case ENXIO:
                return (dgettext(TEXT_DOMAIN, "The ZFS modules are not "
                    "loaded.\nTry running '/sbin/modprobe zfs' as root "
                    "to load them.\n"));
        case ENOENT:
                return (dgettext(TEXT_DOMAIN, "/dev/zfs and /proc/self/mounts "
                    "are required.\nTry running 'udevadm trigger' and 'mount "
                    "-t proc proc /proc' as root.\n"));
        case ENOEXEC:
                return (dgettext(TEXT_DOMAIN, "The ZFS modules cannot be "
                    "auto-loaded.\nTry running '/sbin/modprobe zfs' as "
                    "root to manually load them.\n"));
        case EACCES:
                return (dgettext(TEXT_DOMAIN, "Permission denied the "
                    "ZFS utilities must be run as root.\n"));
        default:
                return (dgettext(TEXT_DOMAIN, "Failed to initialize the "
                    "libzfs library.\n"));
        }
}

const char *
libzfs_error_action(libzfs_handle_t *hdl)
{
        return (hdl->libzfs_action);
}

const char *
libzfs_error_description(libzfs_handle_t *hdl)
{
        if (hdl->libzfs_desc[0] != '\0')
                return (hdl->libzfs_desc);

        switch (hdl->libzfs_error) {
        case EZFS_NOMEM:
                return (dgettext(TEXT_DOMAIN, "out of memory"));
        case EZFS_BADPROP:
                return (dgettext(TEXT_DOMAIN, "invalid property value"));
        case EZFS_PROPREADONLY:
                return (dgettext(TEXT_DOMAIN, "read-only property"));
        case EZFS_PROPTYPE:
                return (dgettext(TEXT_DOMAIN, "property doesn't apply to "
                    "datasets of this type"));
        case EZFS_PROPNONINHERIT:
                return (dgettext(TEXT_DOMAIN, "property cannot be inherited"));
        case EZFS_PROPSPACE:
                return (dgettext(TEXT_DOMAIN, "invalid quota or reservation"));
        case EZFS_BADTYPE:
                return (dgettext(TEXT_DOMAIN, "operation not applicable to "
                    "datasets of this type"));
        case EZFS_BUSY:
                return (dgettext(TEXT_DOMAIN, "pool or dataset is busy"));
        case EZFS_EXISTS:
                return (dgettext(TEXT_DOMAIN, "pool or dataset exists"));
        case EZFS_NOENT:
                return (dgettext(TEXT_DOMAIN, "no such pool or dataset"));
        case EZFS_BADSTREAM:
                return (dgettext(TEXT_DOMAIN, "invalid backup stream"));
        case EZFS_DSREADONLY:
                return (dgettext(TEXT_DOMAIN, "dataset is read-only"));
        case EZFS_VOLTOOBIG:
                return (dgettext(TEXT_DOMAIN, "volume size exceeds limit for "
                    "this system"));
        case EZFS_INVALIDNAME:
                return (dgettext(TEXT_DOMAIN, "invalid name"));
        case EZFS_BADRESTORE:
                return (dgettext(TEXT_DOMAIN, "unable to restore to "
                    "destination"));
        case EZFS_BADBACKUP:
                return (dgettext(TEXT_DOMAIN, "backup failed"));
        case EZFS_BADTARGET:
                return (dgettext(TEXT_DOMAIN, "invalid target vdev"));
        case EZFS_NODEVICE:
                return (dgettext(TEXT_DOMAIN, "no such device in pool"));
        case EZFS_BADDEV:
                return (dgettext(TEXT_DOMAIN, "invalid device"));
        case EZFS_NOREPLICAS:
                return (dgettext(TEXT_DOMAIN, "no valid replicas"));
        case EZFS_RESILVERING:
                return (dgettext(TEXT_DOMAIN, "currently resilvering"));
        case EZFS_BADVERSION:
                return (dgettext(TEXT_DOMAIN, "unsupported version or "
                    "feature"));
        case EZFS_POOLUNAVAIL:
                return (dgettext(TEXT_DOMAIN, "pool is unavailable"));
        case EZFS_DEVOVERFLOW:
                return (dgettext(TEXT_DOMAIN, "too many devices in one vdev"));
        case EZFS_BADPATH:
                return (dgettext(TEXT_DOMAIN, "must be an absolute path"));
        case EZFS_CROSSTARGET:
                return (dgettext(TEXT_DOMAIN, "operation crosses datasets or "
                    "pools"));
        case EZFS_ZONED:
                return (dgettext(TEXT_DOMAIN, "dataset in use by local zone"));
        case EZFS_MOUNTFAILED:
                return (dgettext(TEXT_DOMAIN, "mount failed"));
        case EZFS_UMOUNTFAILED:
                return (dgettext(TEXT_DOMAIN, "umount failed"));
        case EZFS_UNSHARENFSFAILED:
                return (dgettext(TEXT_DOMAIN, "unshare(1M) failed"));
        case EZFS_SHARENFSFAILED:
                return (dgettext(TEXT_DOMAIN, "share(1M) failed"));
        case EZFS_UNSHARESMBFAILED:
                return (dgettext(TEXT_DOMAIN, "smb remove share failed"));
        case EZFS_SHARESMBFAILED:
                return (dgettext(TEXT_DOMAIN, "smb add share failed"));
        case EZFS_PERM:
                return (dgettext(TEXT_DOMAIN, "permission denied"));
        case EZFS_NOSPC:
                return (dgettext(TEXT_DOMAIN, "out of space"));
        case EZFS_FAULT:
                return (dgettext(TEXT_DOMAIN, "bad address"));
        case EZFS_IO:
                return (dgettext(TEXT_DOMAIN, "I/O error"));
        case EZFS_INTR:
                return (dgettext(TEXT_DOMAIN, "signal received"));
        case EZFS_ISSPARE:
                return (dgettext(TEXT_DOMAIN, "device is reserved as a hot "
                    "spare"));
        case EZFS_INVALCONFIG:
                return (dgettext(TEXT_DOMAIN, "invalid vdev configuration"));
        case EZFS_RECURSIVE:
                return (dgettext(TEXT_DOMAIN, "recursive dataset dependency"));
        case EZFS_NOHISTORY:
                return (dgettext(TEXT_DOMAIN, "no history available"));
        case EZFS_POOLPROPS:
                return (dgettext(TEXT_DOMAIN, "failed to retrieve "
                    "pool properties"));
        case EZFS_POOL_NOTSUP:
                return (dgettext(TEXT_DOMAIN, "operation not supported "
                    "on this type of pool"));
        case EZFS_POOL_INVALARG:
                return (dgettext(TEXT_DOMAIN, "invalid argument for "
                    "this pool operation"));
        case EZFS_NAMETOOLONG:
                return (dgettext(TEXT_DOMAIN, "dataset name is too long"));
        case EZFS_OPENFAILED:
                return (dgettext(TEXT_DOMAIN, "open failed"));
        case EZFS_NOCAP:
                return (dgettext(TEXT_DOMAIN,
                    "disk capacity information could not be retrieved"));
        case EZFS_LABELFAILED:
                return (dgettext(TEXT_DOMAIN, "write of label failed"));
        case EZFS_BADWHO:
                return (dgettext(TEXT_DOMAIN, "invalid user/group"));
        case EZFS_BADPERM:
                return (dgettext(TEXT_DOMAIN, "invalid permission"));
        case EZFS_BADPERMSET:
                return (dgettext(TEXT_DOMAIN, "invalid permission set name"));
        case EZFS_NODELEGATION:
                return (dgettext(TEXT_DOMAIN, "delegated administration is "
                    "disabled on pool"));
        case EZFS_BADCACHE:
                return (dgettext(TEXT_DOMAIN, "invalid or missing cache file"));
        case EZFS_ISL2CACHE:
                return (dgettext(TEXT_DOMAIN, "device is in use as a cache"));
        case EZFS_VDEVNOTSUP:
                return (dgettext(TEXT_DOMAIN, "vdev specification is not "
                    "supported"));
        case EZFS_NOTSUP:
                return (dgettext(TEXT_DOMAIN, "operation not supported "
                    "on this dataset"));
        case EZFS_ACTIVE_SPARE:
                return (dgettext(TEXT_DOMAIN, "pool has active shared spare "
                    "device"));
        case EZFS_UNPLAYED_LOGS:
                return (dgettext(TEXT_DOMAIN, "log device has unplayed intent "
                    "logs"));
        case EZFS_REFTAG_RELE:
                return (dgettext(TEXT_DOMAIN, "no such tag on this dataset"));
        case EZFS_REFTAG_HOLD:
                return (dgettext(TEXT_DOMAIN, "tag already exists on this "
                    "dataset"));
        case EZFS_TAGTOOLONG:
                return (dgettext(TEXT_DOMAIN, "tag too long"));
        case EZFS_PIPEFAILED:
                return (dgettext(TEXT_DOMAIN, "pipe create failed"));
        case EZFS_THREADCREATEFAILED:
                return (dgettext(TEXT_DOMAIN, "thread create failed"));
        case EZFS_POSTSPLIT_ONLINE:
                return (dgettext(TEXT_DOMAIN, "disk was split from this pool "
                    "into a new one"));
        case EZFS_SCRUBBING:
                return (dgettext(TEXT_DOMAIN, "currently scrubbing; "
                    "use 'zpool scrub -s' to cancel current scrub"));
        case EZFS_NO_SCRUB:
                return (dgettext(TEXT_DOMAIN, "there is no active scrub"));
        case EZFS_DIFF:
                return (dgettext(TEXT_DOMAIN, "unable to generate diffs"));
        case EZFS_DIFFDATA:
                return (dgettext(TEXT_DOMAIN, "invalid diff data"));
        case EZFS_POOLREADONLY:
                return (dgettext(TEXT_DOMAIN, "pool is read-only"));
        case EZFS_UNKNOWN:
                return (dgettext(TEXT_DOMAIN, "unknown error"));
        default:
                assert(hdl->libzfs_error == 0);
                return (dgettext(TEXT_DOMAIN, "no error"));
        }
}

/*PRINTFLIKE2*/
void
zfs_error_aux(libzfs_handle_t *hdl, const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);

        (void) vsnprintf(hdl->libzfs_desc, sizeof (hdl->libzfs_desc),
            fmt, ap);
        hdl->libzfs_desc_active = 1;

        va_end(ap);
}

static void
zfs_verror(libzfs_handle_t *hdl, int error, const char *fmt, va_list ap)
{
        (void) vsnprintf(hdl->libzfs_action, sizeof (hdl->libzfs_action),
            fmt, ap);
        hdl->libzfs_error = error;

        if (hdl->libzfs_desc_active)
                hdl->libzfs_desc_active = 0;
        else
                hdl->libzfs_desc[0] = '\0';

        if (hdl->libzfs_printerr) {
                if (error == EZFS_UNKNOWN) {
                        (void) fprintf(stderr, dgettext(TEXT_DOMAIN, "internal "
                            "error: %s\n"), libzfs_error_description(hdl));
                        abort();
                }

                (void) fprintf(stderr, "%s: %s\n", hdl->libzfs_action,
                    libzfs_error_description(hdl));
                if (error == EZFS_NOMEM)
                        exit(1);
        }
}

int
zfs_error(libzfs_handle_t *hdl, int error, const char *msg)
{
        return (zfs_error_fmt(hdl, error, "%s", msg));
}

/*PRINTFLIKE3*/
int
zfs_error_fmt(libzfs_handle_t *hdl, int error, const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);

        zfs_verror(hdl, error, fmt, ap);

        va_end(ap);

        return (-1);
}

static int
zfs_common_error(libzfs_handle_t *hdl, int error, const char *fmt,
    va_list ap)
{
        switch (error) {
        case EPERM:
        case EACCES:
                zfs_verror(hdl, EZFS_PERM, fmt, ap);
                return (-1);

        case ECANCELED:
                zfs_verror(hdl, EZFS_NODELEGATION, fmt, ap);
                return (-1);

        case EIO:
                zfs_verror(hdl, EZFS_IO, fmt, ap);
                return (-1);

        case EFAULT:
                zfs_verror(hdl, EZFS_FAULT, fmt, ap);
                return (-1);

        case EINTR:
                zfs_verror(hdl, EZFS_INTR, fmt, ap);
                return (-1);
        }

        return (0);
}

int
zfs_standard_error(libzfs_handle_t *hdl, int error, const char *msg)
{
        return (zfs_standard_error_fmt(hdl, error, "%s", msg));
}

/*PRINTFLIKE3*/
int
zfs_standard_error_fmt(libzfs_handle_t *hdl, int error, const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);

        if (zfs_common_error(hdl, error, fmt, ap) != 0) {
                va_end(ap);
                return (-1);
        }

        switch (error) {
        case ENXIO:
        case ENODEV:
        case EPIPE:
                zfs_verror(hdl, EZFS_IO, fmt, ap);
                break;

        case ENOENT:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "dataset does not exist"));
                zfs_verror(hdl, EZFS_NOENT, fmt, ap);
                break;

        case ENOSPC:
        case EDQUOT:
                zfs_verror(hdl, EZFS_NOSPC, fmt, ap);
                break;

        case EEXIST:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "dataset already exists"));
                zfs_verror(hdl, EZFS_EXISTS, fmt, ap);
                break;

        case EBUSY:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "dataset is busy"));
                zfs_verror(hdl, EZFS_BUSY, fmt, ap);
                break;
        case EROFS:
                zfs_verror(hdl, EZFS_POOLREADONLY, fmt, ap);
                break;
        case ENAMETOOLONG:
                zfs_verror(hdl, EZFS_NAMETOOLONG, fmt, ap);
                break;
        case ENOTSUP:
                zfs_verror(hdl, EZFS_BADVERSION, fmt, ap);
                break;
        case EAGAIN:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "pool I/O is currently suspended"));
                zfs_verror(hdl, EZFS_POOLUNAVAIL, fmt, ap);
                break;
        default:
                zfs_error_aux(hdl, strerror(error));
                zfs_verror(hdl, EZFS_UNKNOWN, fmt, ap);
                break;
        }

        va_end(ap);
        return (-1);
}

int
zpool_standard_error(libzfs_handle_t *hdl, int error, const char *msg)
{
        return (zpool_standard_error_fmt(hdl, error, "%s", msg));
}

/*PRINTFLIKE3*/
int
zpool_standard_error_fmt(libzfs_handle_t *hdl, int error, const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);

        if (zfs_common_error(hdl, error, fmt, ap) != 0) {
                va_end(ap);
                return (-1);
        }

        switch (error) {
        case ENODEV:
                zfs_verror(hdl, EZFS_NODEVICE, fmt, ap);
                break;

        case ENOENT:
                zfs_error_aux(hdl,
                    dgettext(TEXT_DOMAIN, "no such pool or dataset"));
                zfs_verror(hdl, EZFS_NOENT, fmt, ap);
                break;

        case EEXIST:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "pool already exists"));
                zfs_verror(hdl, EZFS_EXISTS, fmt, ap);
                break;

        case EBUSY:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "pool is busy"));
                zfs_verror(hdl, EZFS_BUSY, fmt, ap);
                break;

        case ENXIO:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "one or more devices is currently unavailable"));
                zfs_verror(hdl, EZFS_BADDEV, fmt, ap);
                break;

        case ENAMETOOLONG:
                zfs_verror(hdl, EZFS_DEVOVERFLOW, fmt, ap);
                break;

        case ENOTSUP:
                zfs_verror(hdl, EZFS_POOL_NOTSUP, fmt, ap);
                break;

        case EINVAL:
                zfs_verror(hdl, EZFS_POOL_INVALARG, fmt, ap);
                break;

        case ENOSPC:
        case EDQUOT:
                zfs_verror(hdl, EZFS_NOSPC, fmt, ap);
                return (-1);

        case EAGAIN:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "pool I/O is currently suspended"));
                zfs_verror(hdl, EZFS_POOLUNAVAIL, fmt, ap);
                break;

        case EROFS:
                zfs_verror(hdl, EZFS_POOLREADONLY, fmt, ap);
                break;
        case EDOM:
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "block size out of range or does not match"));
                zfs_verror(hdl, EZFS_BADPROP, fmt, ap);
                break;

        default:
                zfs_error_aux(hdl, strerror(error));
                zfs_verror(hdl, EZFS_UNKNOWN, fmt, ap);
        }

        va_end(ap);
        return (-1);
}

/*
 * Display an out of memory error message and abort the current program.
 */
int
no_memory(libzfs_handle_t *hdl)
{
        return (zfs_error(hdl, EZFS_NOMEM, "internal error"));
}

/*
 * A safe form of malloc() which will die if the allocation fails.
 */
void *
zfs_alloc(libzfs_handle_t *hdl, size_t size)
{
        void *data;

        if ((data = calloc(1, size)) == NULL)
                (void) no_memory(hdl);

        return (data);
}

/*
 * A safe form of asprintf() which will die if the allocation fails.
 */
/*PRINTFLIKE2*/
char *
zfs_asprintf(libzfs_handle_t *hdl, const char *fmt, ...)
{
        va_list ap;
        char *ret;
        int err;

        va_start(ap, fmt);

        err = vasprintf(&ret, fmt, ap);

        va_end(ap);

        if (err < 0)
                (void) no_memory(hdl);

        return (ret);
}

/*
 * A safe form of realloc(), which also zeroes newly allocated space.
 */
void *
zfs_realloc(libzfs_handle_t *hdl, void *ptr, size_t oldsize, size_t newsize)
{
        void *ret;

        if ((ret = realloc(ptr, newsize)) == NULL) {
                (void) no_memory(hdl);
                return (NULL);
        }

        bzero((char *)ret + oldsize, (newsize - oldsize));
        return (ret);
}

/*
 * A safe form of strdup() which will die if the allocation fails.
 */
char *
zfs_strdup(libzfs_handle_t *hdl, const char *str)
{
        char *ret;

        if ((ret = strdup(str)) == NULL)
                (void) no_memory(hdl);

        return (ret);
}

/*
 * Convert a number to an appropriately human-readable output.
 */
void
zfs_nicenum_format(uint64_t num, char *buf, size_t buflen,
    enum zfs_nicenum_format format)
{
        uint64_t n = num;
        int index = 0;
        const char *u;
        const char *units[3][7] = {
            [ZFS_NICENUM_1024] = {"", "K", "M", "G", "T", "P", "E"},
            [ZFS_NICENUM_TIME] = {"ns", "us", "ms", "s", "?", "?", "?"}
        };

        const int units_len[] = {[ZFS_NICENUM_1024] = 6,
            [ZFS_NICENUM_TIME] = 4};

        const int k_unit[] = {  [ZFS_NICENUM_1024] = 1024,
            [ZFS_NICENUM_TIME] = 1000};

        double val;

        if (format == ZFS_NICENUM_RAW) {
                snprintf(buf, buflen, "%llu", (u_longlong_t) num);
                return;
        }


        while (n >= k_unit[format] && index < units_len[format]) {
                n /= k_unit[format];
                index++;
        }

        u = units[format][index];

        /* Don't print 0ns times */
        if ((format == ZFS_NICENUM_TIME) && (num == 0)) {
                (void) snprintf(buf, buflen, "-");
        } else if ((index == 0) || ((num %
            (uint64_t) powl(k_unit[format], index)) == 0)) {
                /*
                 * If this is an even multiple of the base, always display
                 * without any decimal precision.
                 */
                (void) snprintf(buf, buflen, "%llu%s", (u_longlong_t) n, u);

        } else {
                /*
                 * We want to choose a precision that reflects the best choice
                 * for fitting in 5 characters.  This can get rather tricky when
                 * we have numbers that are very close to an order of magnitude.
                 * For example, when displaying 10239 (which is really 9.999K),
                 * we want only a single place of precision for 10.0K.  We could
                 * develop some complex heuristics for this, but it's much
                 * easier just to try each combination in turn.
                 */
                int i;
                for (i = 2; i >= 0; i--) {
                        val = (double) num /
                            (uint64_t) powl(k_unit[format], index);

                        /*
                         * Don't print floating point values for time.  Note,
                         * we use floor() instead of round() here, since
                         * round can result in undesirable results.  For
                         * example, if "num" is in the range of
                         * 999500-999999, it will print out "1000us".  This
                         * doesn't happen if we use floor().
                         */
                        if (format == ZFS_NICENUM_TIME) {
                                if (snprintf(buf, buflen, "%d%s",
                                    (unsigned int) floor(val), u) <= 5)
                                        break;

                        } else {
                                if (snprintf(buf, buflen, "%.*f%s", i,
                                    val, u) <= 5)
                                        break;
                        }
                }
        }
}

/*
 * Convert a number to an appropriately human-readable output.
 */
void
zfs_nicenum(uint64_t num, char *buf, size_t buflen)
{
        zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_1024);
}

/*
 * Convert a time to an appropriately human-readable output.
 * @num:        Time in nanoseconds
 */
void
zfs_nicetime(uint64_t num, char *buf, size_t buflen)
{
        zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_TIME);
}

/*
 * Print out a raw number with correct column spacing
 */
void
zfs_niceraw(uint64_t num, char *buf, size_t buflen)
{
        zfs_nicenum_format(num, buf, buflen, ZFS_NICENUM_RAW);
}



void
libzfs_print_on_error(libzfs_handle_t *hdl, boolean_t printerr)
{
        hdl->libzfs_printerr = printerr;
}

static int
libzfs_module_loaded(const char *module)
{
        const char path_prefix[] = "/sys/module/";
        char path[256];

        memcpy(path, path_prefix, sizeof (path_prefix) - 1);
        strcpy(path + sizeof (path_prefix) - 1, module);

        return (access(path, F_OK) == 0);
}

int
libzfs_run_process(const char *path, char *argv[], int flags)
{
        pid_t pid;
        int error, devnull_fd;

        pid = vfork();
        if (pid == 0) {
                devnull_fd = open("/dev/null", O_WRONLY);

                if (devnull_fd < 0)
                        _exit(-1);

                if (!(flags & STDOUT_VERBOSE))
                        (void) dup2(devnull_fd, STDOUT_FILENO);

                if (!(flags & STDERR_VERBOSE))
                        (void) dup2(devnull_fd, STDERR_FILENO);

                close(devnull_fd);

                (void) execvp(path, argv);
                _exit(-1);
        } else if (pid > 0) {
                int status;

                while ((error = waitpid(pid, &status, 0)) == -1 &&
                        errno == EINTR);
                if (error < 0 || !WIFEXITED(status))
                        return (-1);

                return (WEXITSTATUS(status));
        }

        return (-1);
}

/*
 * Verify the required ZFS_DEV device is available and optionally attempt
 * to load the ZFS modules.  Under normal circumstances the modules
 * should already have been loaded by some external mechanism.
 *
 * Environment variables:
 * - ZFS_MODULE_LOADING="YES|yes|ON|on" - Attempt to load modules.
 * - ZFS_MODULE_TIMEOUT="<seconds>"     - Seconds to wait for ZFS_DEV
 */
static int
libzfs_load_module(const char *module)
{
        char *argv[4] = {"/sbin/modprobe", "-q", (char *)module, (char *)0};
        char *load_str, *timeout_str;
        long timeout = 10; /* seconds */
        long busy_timeout = 10; /* milliseconds */
        int load = 0, fd;
        hrtime_t start;

        /* Optionally request module loading */
        if (!libzfs_module_loaded(module)) {
                load_str = getenv("ZFS_MODULE_LOADING");
                if (load_str) {
                        if (!strncasecmp(load_str, "YES", strlen("YES")) ||
                            !strncasecmp(load_str, "ON", strlen("ON")))
                                load = 1;
                        else
                                load = 0;
                }

                if (load && libzfs_run_process("/sbin/modprobe", argv, 0))
                        return (ENOEXEC);
        }

        /* Module loading is synchronous it must be available */
        if (!libzfs_module_loaded(module))
                return (ENXIO);

        /*
         * Device creation by udev is asynchronous and waiting may be
         * required.  Busy wait for 10ms and then fall back to polling every
         * 10ms for the allowed timeout (default 10s, max 10m).  This is
         * done to optimize for the common case where the device is
         * immediately available and to avoid penalizing the possible
         * case where udev is slow or unable to create the device.
         */
        timeout_str = getenv("ZFS_MODULE_TIMEOUT");
        if (timeout_str) {
                timeout = strtol(timeout_str, NULL, 0);
                timeout = MAX(MIN(timeout, (10 * 60)), 0); /* 0 <= N <= 600 */
        }

        start = gethrtime();
        do {
                fd = open(ZFS_DEV, O_RDWR);
                if (fd >= 0) {
                        (void) close(fd);
                        return (0);
                } else if (errno != ENOENT) {
                        return (errno);
                } else if (NSEC2MSEC(gethrtime() - start) < busy_timeout) {
                        sched_yield();
                } else {
                        usleep(10 * MILLISEC);
                }
        } while (NSEC2MSEC(gethrtime() - start) < (timeout * MILLISEC));

        return (ENOENT);
}

libzfs_handle_t *
libzfs_init(void)
{
        libzfs_handle_t *hdl;
        int error;

        error = libzfs_load_module(ZFS_DRIVER);
        if (error) {
                errno = error;
                return (NULL);
        }

        if ((hdl = calloc(1, sizeof (libzfs_handle_t))) == NULL) {
                return (NULL);
        }

        if ((hdl->libzfs_fd = open(ZFS_DEV, O_RDWR)) < 0) {
                free(hdl);
                return (NULL);
        }

#ifdef HAVE_SETMNTENT
        if ((hdl->libzfs_mnttab = setmntent(MNTTAB, "r")) == NULL) {
#else
        if ((hdl->libzfs_mnttab = fopen(MNTTAB, "r")) == NULL) {
#endif
                (void) close(hdl->libzfs_fd);
                free(hdl);
                return (NULL);
        }

        hdl->libzfs_sharetab = fopen("/etc/dfs/sharetab", "r");

        if (libzfs_core_init() != 0) {
                (void) close(hdl->libzfs_fd);
                (void) fclose(hdl->libzfs_mnttab);
                (void) fclose(hdl->libzfs_sharetab);
                free(hdl);
                return (NULL);
        }

        zfs_prop_init();
        zpool_prop_init();
        zpool_feature_init();
        libzfs_mnttab_init(hdl);
        fletcher_4_init();

        return (hdl);
}

void
libzfs_fini(libzfs_handle_t *hdl)
{
        (void) close(hdl->libzfs_fd);
        if (hdl->libzfs_mnttab)
#ifdef HAVE_SETMNTENT
                (void) endmntent(hdl->libzfs_mnttab);
#else
                (void) fclose(hdl->libzfs_mnttab);
#endif
        if (hdl->libzfs_sharetab)
                (void) fclose(hdl->libzfs_sharetab);
        zfs_uninit_libshare(hdl);
        zpool_free_handles(hdl);
        libzfs_fru_clear(hdl, B_TRUE);
        namespace_clear(hdl);
        libzfs_mnttab_fini(hdl);
        libzfs_core_fini();
        fletcher_4_fini();
        free(hdl);
}

libzfs_handle_t *
zpool_get_handle(zpool_handle_t *zhp)
{
        return (zhp->zpool_hdl);
}

libzfs_handle_t *
zfs_get_handle(zfs_handle_t *zhp)
{
        return (zhp->zfs_hdl);
}

zpool_handle_t *
zfs_get_pool_handle(const zfs_handle_t *zhp)
{
        return (zhp->zpool_hdl);
}

/*
 * Given a name, determine whether or not it's a valid path
 * (starts with '/' or "./").  If so, walk the mnttab trying
 * to match the device number.  If not, treat the path as an
 * fs/vol/snap name.
 */
zfs_handle_t *
zfs_path_to_zhandle(libzfs_handle_t *hdl, char *path, zfs_type_t argtype)
{
        struct stat64 statbuf;
        struct extmnttab entry;
        int ret;

        if (path[0] != '/' && strncmp(path, "./", strlen("./")) != 0) {
                /*
                 * It's not a valid path, assume it's a name of type 'argtype'.
                 */
                return (zfs_open(hdl, path, argtype));
        }

        if (stat64(path, &statbuf) != 0) {
                (void) fprintf(stderr, "%s: %s\n", path, strerror(errno));
                return (NULL);
        }

        /* Reopen MNTTAB to prevent reading stale data from open file */
        if (freopen(MNTTAB, "r", hdl->libzfs_mnttab) == NULL)
                return (NULL);

        while ((ret = getextmntent(hdl->libzfs_mnttab, &entry, 0)) == 0) {
                if (makedevice(entry.mnt_major, entry.mnt_minor) ==
                    statbuf.st_dev) {
                        break;
                }
        }
        if (ret != 0) {
                return (NULL);
        }

        if (strcmp(entry.mnt_fstype, MNTTYPE_ZFS) != 0) {
                (void) fprintf(stderr, gettext("'%s': not a ZFS filesystem\n"),
                    path);
                return (NULL);
        }

        return (zfs_open(hdl, entry.mnt_special, ZFS_TYPE_FILESYSTEM));
}

/*
 * Append partition suffix to an otherwise fully qualified device path.
 * This is used to generate the name the full path as its stored in
 * ZPOOL_CONFIG_PATH for whole disk devices.  On success the new length
 * of 'path' will be returned on error a negative value is returned.
 */
int
zfs_append_partition(char *path, size_t max_len)
{
        int len = strlen(path);

        if ((strncmp(path, UDISK_ROOT, strlen(UDISK_ROOT)) == 0) ||
            (strncmp(path, ZVOL_ROOT, strlen(ZVOL_ROOT)) == 0)) {
                if (len + 6 >= max_len)
                        return (-1);

                (void) strcat(path, "-part1");
                len += 6;
        } else {
                if (len + 2 >= max_len)
                        return (-1);

                if (isdigit(path[len-1])) {
                        (void) strcat(path, "p1");
                        len += 2;
                } else {
                        (void) strcat(path, "1");
                        len += 1;
                }
        }

        return (len);
}

/*
 * Given a shorthand device name check if a file by that name exists in any
 * of the 'zpool_default_import_path' or ZPOOL_IMPORT_PATH directories.  If
 * one is found, store its fully qualified path in the 'path' buffer passed
 * by the caller and return 0, otherwise return an error.
 */
int
zfs_resolve_shortname(const char *name, char *path, size_t len)
{
        int i, error = -1;
        char *dir, *env, *envdup;

        env = getenv("ZPOOL_IMPORT_PATH");
        errno = ENOENT;

        if (env) {
                envdup = strdup(env);
                dir = strtok(envdup, ":");
                while (dir && error) {
                        (void) snprintf(path, len, "%s/%s", dir, name);
                        error = access(path, F_OK);
                        dir = strtok(NULL, ":");
                }
                free(envdup);
        } else {
                for (i = 0; i < DEFAULT_IMPORT_PATH_SIZE && error < 0; i++) {
                        (void) snprintf(path, len, "%s/%s",
                            zpool_default_import_path[i], name);
                        error = access(path, F_OK);
                }
        }

        return (error ? ENOENT : 0);
}

/*
 * Given a shorthand device name look for a match against 'cmp_name'.  This
 * is done by checking all prefix expansions using either the default
 * 'zpool_default_import_paths' or the ZPOOL_IMPORT_PATH environment
 * variable.  Proper partition suffixes will be appended if this is a
 * whole disk.  When a match is found 0 is returned otherwise ENOENT.
 */
static int
zfs_strcmp_shortname(char *name, char *cmp_name, int wholedisk)
{
        int path_len, cmp_len, i = 0, error = ENOENT;
        char *dir, *env, *envdup = NULL;
        char path_name[MAXPATHLEN];

        cmp_len = strlen(cmp_name);
        env = getenv("ZPOOL_IMPORT_PATH");

        if (env) {
                envdup = strdup(env);
                dir = strtok(envdup, ":");
        } else {
                dir =  zpool_default_import_path[i];
        }

        while (dir) {
                /* Trim trailing directory slashes from ZPOOL_IMPORT_PATH */
                while (dir[strlen(dir)-1] == '/')
                        dir[strlen(dir)-1] = '\0';

                path_len = snprintf(path_name, MAXPATHLEN, "%s/%s", dir, name);
                if (wholedisk)
                        path_len = zfs_append_partition(path_name, MAXPATHLEN);

                if ((path_len == cmp_len) && strcmp(path_name, cmp_name) == 0) {
                        error = 0;
                        break;
                }

                if (env) {
                        dir = strtok(NULL, ":");
                } else if (++i < DEFAULT_IMPORT_PATH_SIZE) {
                        dir = zpool_default_import_path[i];
                } else {
                        dir = NULL;
                }
        }

        if (env)
                free(envdup);

        return (error);
}

/*
 * Given either a shorthand or fully qualified path name look for a match
 * against 'cmp'.  The passed name will be expanded as needed for comparison
 * purposes and redundant slashes stripped to ensure an accurate match.
 */
int
zfs_strcmp_pathname(char *name, char *cmp, int wholedisk)
{
        int path_len, cmp_len;
        char path_name[MAXPATHLEN];
        char cmp_name[MAXPATHLEN];
        char *dir, *dup;

        /* Strip redundant slashes if one exists due to ZPOOL_IMPORT_PATH */
        memset(cmp_name, 0, MAXPATHLEN);
        dup = strdup(cmp);
        dir = strtok(dup, "/");
        while (dir) {
                strlcat(cmp_name, "/", sizeof (cmp_name));
                strlcat(cmp_name, dir, sizeof (cmp_name));
                dir = strtok(NULL, "/");
        }
        free(dup);

        if (name[0] != '/')
                return (zfs_strcmp_shortname(name, cmp_name, wholedisk));

        (void) strlcpy(path_name, name, MAXPATHLEN);
        path_len = strlen(path_name);
        cmp_len = strlen(cmp_name);

        if (wholedisk) {
                path_len = zfs_append_partition(path_name, MAXPATHLEN);
                if (path_len == -1)
                        return (ENOMEM);
        }

        if ((path_len != cmp_len) || strcmp(path_name, cmp_name))
                return (ENOENT);

        return (0);
}

/*
 * Initialize the zc_nvlist_dst member to prepare for receiving an nvlist from
 * an ioctl().
 */
int
zcmd_alloc_dst_nvlist(libzfs_handle_t *hdl, zfs_cmd_t *zc, size_t len)
{
        if (len == 0)
                len = 16 * 1024;
        zc->zc_nvlist_dst_size = len;
        zc->zc_nvlist_dst =
            (uint64_t)(uintptr_t)zfs_alloc(hdl, zc->zc_nvlist_dst_size);
        if (zc->zc_nvlist_dst == 0)
                return (-1);

        return (0);
}

/*
 * Called when an ioctl() which returns an nvlist fails with ENOMEM.  This will
 * expand the nvlist to the size specified in 'zc_nvlist_dst_size', which was
 * filled in by the kernel to indicate the actual required size.
 */
int
zcmd_expand_dst_nvlist(libzfs_handle_t *hdl, zfs_cmd_t *zc)
{
        free((void *)(uintptr_t)zc->zc_nvlist_dst);
        zc->zc_nvlist_dst =
            (uint64_t)(uintptr_t)zfs_alloc(hdl, zc->zc_nvlist_dst_size);
        if (zc->zc_nvlist_dst == 0)
                return (-1);

        return (0);
}

/*
 * Called to free the src and dst nvlists stored in the command structure.
 */
void
zcmd_free_nvlists(zfs_cmd_t *zc)
{
        free((void *)(uintptr_t)zc->zc_nvlist_conf);
        free((void *)(uintptr_t)zc->zc_nvlist_src);
        free((void *)(uintptr_t)zc->zc_nvlist_dst);
        zc->zc_nvlist_conf = 0;
        zc->zc_nvlist_src = 0;
        zc->zc_nvlist_dst = 0;
}

static int
zcmd_write_nvlist_com(libzfs_handle_t *hdl, uint64_t *outnv, uint64_t *outlen,
    nvlist_t *nvl)
{
        char *packed;
        size_t len;

        verify(nvlist_size(nvl, &len, NV_ENCODE_NATIVE) == 0);

        if ((packed = zfs_alloc(hdl, len)) == NULL)
                return (-1);

        verify(nvlist_pack(nvl, &packed, &len, NV_ENCODE_NATIVE, 0) == 0);

        *outnv = (uint64_t)(uintptr_t)packed;
        *outlen = len;

        return (0);
}

int
zcmd_write_conf_nvlist(libzfs_handle_t *hdl, zfs_cmd_t *zc, nvlist_t *nvl)
{
        return (zcmd_write_nvlist_com(hdl, &zc->zc_nvlist_conf,
            &zc->zc_nvlist_conf_size, nvl));
}

int
zcmd_write_src_nvlist(libzfs_handle_t *hdl, zfs_cmd_t *zc, nvlist_t *nvl)
{
        return (zcmd_write_nvlist_com(hdl, &zc->zc_nvlist_src,
            &zc->zc_nvlist_src_size, nvl));
}

/*
 * Unpacks an nvlist from the ZFS ioctl command structure.
 */
int
zcmd_read_dst_nvlist(libzfs_handle_t *hdl, zfs_cmd_t *zc, nvlist_t **nvlp)
{
        if (nvlist_unpack((void *)(uintptr_t)zc->zc_nvlist_dst,
            zc->zc_nvlist_dst_size, nvlp, 0) != 0)
                return (no_memory(hdl));

        return (0);
}

int
zfs_ioctl(libzfs_handle_t *hdl, int request, zfs_cmd_t *zc)
{
        return (ioctl(hdl->libzfs_fd, request, zc));
}

/*
 * ================================================================
 * API shared by zfs and zpool property management
 * ================================================================
 */

static void
zprop_print_headers(zprop_get_cbdata_t *cbp, zfs_type_t type)
{
        zprop_list_t *pl = cbp->cb_proplist;
        int i;
        char *title;
        size_t len;

        cbp->cb_first = B_FALSE;
        if (cbp->cb_scripted)
                return;

        /*
         * Start with the length of the column headers.
         */
        cbp->cb_colwidths[GET_COL_NAME] = strlen(dgettext(TEXT_DOMAIN, "NAME"));
        cbp->cb_colwidths[GET_COL_PROPERTY] = strlen(dgettext(TEXT_DOMAIN,
            "PROPERTY"));
        cbp->cb_colwidths[GET_COL_VALUE] = strlen(dgettext(TEXT_DOMAIN,
            "VALUE"));
        cbp->cb_colwidths[GET_COL_RECVD] = strlen(dgettext(TEXT_DOMAIN,
            "RECEIVED"));
        cbp->cb_colwidths[GET_COL_SOURCE] = strlen(dgettext(TEXT_DOMAIN,
            "SOURCE"));

        /* first property is always NAME */
        assert(cbp->cb_proplist->pl_prop ==
            ((type == ZFS_TYPE_POOL) ?  ZPOOL_PROP_NAME : ZFS_PROP_NAME));

        /*
         * Go through and calculate the widths for each column.  For the
         * 'source' column, we kludge it up by taking the worst-case scenario of
         * inheriting from the longest name.  This is acceptable because in the
         * majority of cases 'SOURCE' is the last column displayed, and we don't
         * use the width anyway.  Note that the 'VALUE' column can be oversized,
         * if the name of the property is much longer than any values we find.
         */
        for (pl = cbp->cb_proplist; pl != NULL; pl = pl->pl_next) {
                /*
                 * 'PROPERTY' column
                 */
                if (pl->pl_prop != ZPROP_INVAL) {
                        const char *propname = (type == ZFS_TYPE_POOL) ?
                            zpool_prop_to_name(pl->pl_prop) :
                            zfs_prop_to_name(pl->pl_prop);

                        len = strlen(propname);
                        if (len > cbp->cb_colwidths[GET_COL_PROPERTY])
                                cbp->cb_colwidths[GET_COL_PROPERTY] = len;
                } else {
                        len = strlen(pl->pl_user_prop);
                        if (len > cbp->cb_colwidths[GET_COL_PROPERTY])
                                cbp->cb_colwidths[GET_COL_PROPERTY] = len;
                }

                /*
                 * 'VALUE' column.  The first property is always the 'name'
                 * property that was tacked on either by /sbin/zfs's
                 * zfs_do_get() or when calling zprop_expand_list(), so we
                 * ignore its width.  If the user specified the name property
                 * to display, then it will be later in the list in any case.
                 */
                if (pl != cbp->cb_proplist &&
                    pl->pl_width > cbp->cb_colwidths[GET_COL_VALUE])
                        cbp->cb_colwidths[GET_COL_VALUE] = pl->pl_width;

                /* 'RECEIVED' column. */
                if (pl != cbp->cb_proplist &&
                    pl->pl_recvd_width > cbp->cb_colwidths[GET_COL_RECVD])
                        cbp->cb_colwidths[GET_COL_RECVD] = pl->pl_recvd_width;

                /*
                 * 'NAME' and 'SOURCE' columns
                 */
                if (pl->pl_prop == (type == ZFS_TYPE_POOL ? ZPOOL_PROP_NAME :
                    ZFS_PROP_NAME) &&
                    pl->pl_width > cbp->cb_colwidths[GET_COL_NAME]) {
                        cbp->cb_colwidths[GET_COL_NAME] = pl->pl_width;
                        cbp->cb_colwidths[GET_COL_SOURCE] = pl->pl_width +
                            strlen(dgettext(TEXT_DOMAIN, "inherited from"));
                }
        }

        /*
         * Now go through and print the headers.
         */
        for (i = 0; i < ZFS_GET_NCOLS; i++) {
                switch (cbp->cb_columns[i]) {
                case GET_COL_NAME:
                        title = dgettext(TEXT_DOMAIN, "NAME");
                        break;
                case GET_COL_PROPERTY:
                        title = dgettext(TEXT_DOMAIN, "PROPERTY");
                        break;
                case GET_COL_VALUE:
                        title = dgettext(TEXT_DOMAIN, "VALUE");
                        break;
                case GET_COL_RECVD:
                        title = dgettext(TEXT_DOMAIN, "RECEIVED");
                        break;
                case GET_COL_SOURCE:
                        title = dgettext(TEXT_DOMAIN, "SOURCE");
                        break;
                default:
                        title = NULL;
                }

                if (title != NULL) {
                        if (i == (ZFS_GET_NCOLS - 1) ||
                            cbp->cb_columns[i + 1] == GET_COL_NONE)
                                (void) printf("%s", title);
                        else
                                (void) printf("%-*s  ",
                                    cbp->cb_colwidths[cbp->cb_columns[i]],
                                    title);
                }
        }
        (void) printf("\n");
}

/*
 * Display a single line of output, according to the settings in the callback
 * structure.
 */
void
zprop_print_one_property(const char *name, zprop_get_cbdata_t *cbp,
    const char *propname, const char *value, zprop_source_t sourcetype,
    const char *source, const char *recvd_value)
{
        int i;
        const char *str = NULL;
        char buf[128];

        /*
         * Ignore those source types that the user has chosen to ignore.
         */
        if ((sourcetype & cbp->cb_sources) == 0)
                return;

        if (cbp->cb_first)
                zprop_print_headers(cbp, cbp->cb_type);

        for (i = 0; i < ZFS_GET_NCOLS; i++) {
                switch (cbp->cb_columns[i]) {
                case GET_COL_NAME:
                        str = name;
                        break;

                case GET_COL_PROPERTY:
                        str = propname;
                        break;

                case GET_COL_VALUE:
                        str = value;
                        break;

                case GET_COL_SOURCE:
                        switch (sourcetype) {
                        case ZPROP_SRC_NONE:
                                str = "-";
                                break;

                        case ZPROP_SRC_DEFAULT:
                                str = "default";
                                break;

                        case ZPROP_SRC_LOCAL:
                                str = "local";
                                break;

                        case ZPROP_SRC_TEMPORARY:
                                str = "temporary";
                                break;

                        case ZPROP_SRC_INHERITED:
                                (void) snprintf(buf, sizeof (buf),
                                    "inherited from %s", source);
                                str = buf;
                                break;
                        case ZPROP_SRC_RECEIVED:
                                str = "received";
                                break;
                        }
                        break;

                case GET_COL_RECVD:
                        str = (recvd_value == NULL ? "-" : recvd_value);
                        break;

                default:
                        continue;
                }

                if (i == (ZFS_GET_NCOLS - 1) ||
                    cbp->cb_columns[i + 1] == GET_COL_NONE)
                        (void) printf("%s", str);
                else if (cbp->cb_scripted)
                        (void) printf("%s\t", str);
                else
                        (void) printf("%-*s  ",
                            cbp->cb_colwidths[cbp->cb_columns[i]],
                            str);
        }

        (void) printf("\n");
}

/*
 * Given a numeric suffix, convert the value into a number of bits that the
 * resulting value must be shifted.
 */
static int
str2shift(libzfs_handle_t *hdl, const char *buf)
{
        const char *ends = "BKMGTPEZ";
        int i;

        if (buf[0] == '\0')
                return (0);
        for (i = 0; i < strlen(ends); i++) {
                if (toupper(buf[0]) == ends[i])
                        break;
        }
        if (i == strlen(ends)) {
                if (hdl)
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "invalid numeric suffix '%s'"), buf);
                return (-1);
        }

        /*
         * Allow 'G' = 'GB' = 'GiB', case-insensitively.
         * However, 'BB' and 'BiB' are disallowed.
         */
        if (buf[1] == '\0' ||
            (toupper(buf[0]) != 'B' &&
            ((toupper(buf[1]) == 'B' && buf[2] == '\0') ||
            (toupper(buf[1]) == 'I' && toupper(buf[2]) == 'B' &&
            buf[3] == '\0'))))
                return (10 * i);

        if (hdl)
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "invalid numeric suffix '%s'"), buf);
        return (-1);
}

/*
 * Convert a string of the form '100G' into a real number.  Used when setting
 * properties or creating a volume.  'buf' is used to place an extended error
 * message for the caller to use.
 */
int
zfs_nicestrtonum(libzfs_handle_t *hdl, const char *value, uint64_t *num)
{
        char *end;
        int shift;

        *num = 0;

        /* Check to see if this looks like a number.  */
        if ((value[0] < '0' || value[0] > '9') && value[0] != '.') {
                if (hdl)
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "bad numeric value '%s'"), value);
                return (-1);
        }

        /* Rely on strtoull() to process the numeric portion.  */
        errno = 0;
        *num = strtoull(value, &end, 10);

        /*
         * Check for ERANGE, which indicates that the value is too large to fit
         * in a 64-bit value.
         */
        if (errno == ERANGE) {
                if (hdl)
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "numeric value is too large"));
                return (-1);
        }

        /*
         * If we have a decimal value, then do the computation with floating
         * point arithmetic.  Otherwise, use standard arithmetic.
         */
        if (*end == '.') {
                double fval = strtod(value, &end);

                if ((shift = str2shift(hdl, end)) == -1)
                        return (-1);

                fval *= pow(2, shift);

                if (fval > UINT64_MAX) {
                        if (hdl)
                                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                                    "numeric value is too large"));
                        return (-1);
                }

                *num = (uint64_t)fval;
        } else {
                if ((shift = str2shift(hdl, end)) == -1)
                        return (-1);

                /* Check for overflow */
                if (shift >= 64 || (*num << shift) >> shift != *num) {
                        if (hdl)
                                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                                    "numeric value is too large"));
                        return (-1);
                }

                *num <<= shift;
        }

        return (0);
}

/*
 * Given a propname=value nvpair to set, parse any numeric properties
 * (index, boolean, etc) if they are specified as strings and add the
 * resulting nvpair to the returned nvlist.
 *
 * At the DSL layer, all properties are either 64-bit numbers or strings.
 * We want the user to be able to ignore this fact and specify properties
 * as native values (numbers, for example) or as strings (to simplify
 * command line utilities).  This also handles converting index types
 * (compression, checksum, etc) from strings to their on-disk index.
 */
int
zprop_parse_value(libzfs_handle_t *hdl, nvpair_t *elem, int prop,
    zfs_type_t type, nvlist_t *ret, char **svalp, uint64_t *ivalp,
    const char *errbuf)
{
        data_type_t datatype = nvpair_type(elem);
        zprop_type_t proptype;
        const char *propname;
        char *value;
        boolean_t isnone = B_FALSE;

        if (type == ZFS_TYPE_POOL) {
                proptype = zpool_prop_get_type(prop);
                propname = zpool_prop_to_name(prop);
        } else {
                proptype = zfs_prop_get_type(prop);
                propname = zfs_prop_to_name(prop);
        }

        /*
         * Convert any properties to the internal DSL value types.
         */
        *svalp = NULL;
        *ivalp = 0;

        switch (proptype) {
        case PROP_TYPE_STRING:
                if (datatype != DATA_TYPE_STRING) {
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "'%s' must be a string"), nvpair_name(elem));
                        goto error;
                }
                (void) nvpair_value_string(elem, svalp);
                if (strlen(*svalp) >= ZFS_MAXPROPLEN) {
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "'%s' is too long"), nvpair_name(elem));
                        goto error;
                }
                break;

        case PROP_TYPE_NUMBER:
                if (datatype == DATA_TYPE_STRING) {
                        (void) nvpair_value_string(elem, &value);
                        if (strcmp(value, "none") == 0) {
                                isnone = B_TRUE;
                        } else if (zfs_nicestrtonum(hdl, value, ivalp)
                            != 0) {
                                goto error;
                        }
                } else if (datatype == DATA_TYPE_UINT64) {
                        (void) nvpair_value_uint64(elem, ivalp);
                } else {
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "'%s' must be a number"), nvpair_name(elem));
                        goto error;
                }

                /*
                 * Quota special: force 'none' and don't allow 0.
                 */
                if ((type & ZFS_TYPE_DATASET) && *ivalp == 0 && !isnone &&
                    (prop == ZFS_PROP_QUOTA || prop == ZFS_PROP_REFQUOTA)) {
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "use 'none' to disable quota/refquota"));
                        goto error;
                }

                /*
                 * Special handling for "*_limit=none". In this case it's not
                 * 0 but UINT64_MAX.
                 */
                if ((type & ZFS_TYPE_DATASET) && isnone &&
                    (prop == ZFS_PROP_FILESYSTEM_LIMIT ||
                    prop == ZFS_PROP_SNAPSHOT_LIMIT)) {
                        *ivalp = UINT64_MAX;
                }
                break;

        case PROP_TYPE_INDEX:
                if (datatype != DATA_TYPE_STRING) {
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "'%s' must be a string"), nvpair_name(elem));
                        goto error;
                }

                (void) nvpair_value_string(elem, &value);

                if (zprop_string_to_index(prop, value, ivalp, type) != 0) {
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "'%s' must be one of '%s'"), propname,
                            zprop_values(prop, type));
                        goto error;
                }
                break;

        default:
                abort();
        }

        /*
         * Add the result to our return set of properties.
         */
        if (*svalp != NULL) {
                if (nvlist_add_string(ret, propname, *svalp) != 0) {
                        (void) no_memory(hdl);
                        return (-1);
                }
        } else {
                if (nvlist_add_uint64(ret, propname, *ivalp) != 0) {
                        (void) no_memory(hdl);
                        return (-1);
                }
        }

        return (0);
error:
        (void) zfs_error(hdl, EZFS_BADPROP, errbuf);
        return (-1);
}

static int
addlist(libzfs_handle_t *hdl, char *propname, zprop_list_t **listp,
    zfs_type_t type)
{
        int prop;
        zprop_list_t *entry;

        prop = zprop_name_to_prop(propname, type);

        if (prop != ZPROP_INVAL && !zprop_valid_for_type(prop, type, B_FALSE))
                prop = ZPROP_INVAL;

        /*
         * When no property table entry can be found, return failure if
         * this is a pool property or if this isn't a user-defined
         * dataset property,
         */
        if (prop == ZPROP_INVAL && ((type == ZFS_TYPE_POOL &&
            !zpool_prop_feature(propname) &&
            !zpool_prop_unsupported(propname)) ||
            (type == ZFS_TYPE_DATASET && !zfs_prop_user(propname) &&
            !zfs_prop_userquota(propname) && !zfs_prop_written(propname)))) {
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "invalid property '%s'"), propname);
                return (zfs_error(hdl, EZFS_BADPROP,
                    dgettext(TEXT_DOMAIN, "bad property list")));
        }

        if ((entry = zfs_alloc(hdl, sizeof (zprop_list_t))) == NULL)
                return (-1);

        entry->pl_prop = prop;
        if (prop == ZPROP_INVAL) {
                if ((entry->pl_user_prop = zfs_strdup(hdl, propname)) ==
                    NULL) {
                        free(entry);
                        return (-1);
                }
                entry->pl_width = strlen(propname);
        } else {
                entry->pl_width = zprop_width(prop, &entry->pl_fixed,
                    type);
        }

        *listp = entry;

        return (0);
}

/*
 * Given a comma-separated list of properties, construct a property list
 * containing both user-defined and native properties.  This function will
 * return a NULL list if 'all' is specified, which can later be expanded
 * by zprop_expand_list().
 */
int
zprop_get_list(libzfs_handle_t *hdl, char *props, zprop_list_t **listp,
    zfs_type_t type)
{
        *listp = NULL;

        /*
         * If 'all' is specified, return a NULL list.
         */
        if (strcmp(props, "all") == 0)
                return (0);

        /*
         * If no props were specified, return an error.
         */
        if (props[0] == '\0') {
                zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                    "no properties specified"));
                return (zfs_error(hdl, EZFS_BADPROP, dgettext(TEXT_DOMAIN,
                    "bad property list")));
        }

        /*
         * It would be nice to use getsubopt() here, but the inclusion of column
         * aliases makes this more effort than it's worth.
         */
        while (*props != '\0') {
                size_t len;
                char *p;
                char c;

                if ((p = strchr(props, ',')) == NULL) {
                        len = strlen(props);
                        p = props + len;
                } else {
                        len = p - props;
                }

                /*
                 * Check for empty options.
                 */
                if (len == 0) {
                        zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                            "empty property name"));
                        return (zfs_error(hdl, EZFS_BADPROP,
                            dgettext(TEXT_DOMAIN, "bad property list")));
                }

                /*
                 * Check all regular property names.
                 */
                c = props[len];
                props[len] = '\0';

                if (strcmp(props, "space") == 0) {
                        static char *spaceprops[] = {
                                "name", "avail", "used", "usedbysnapshots",
                                "usedbydataset", "usedbyrefreservation",
                                "usedbychildren", NULL
                        };
                        int i;

                        for (i = 0; spaceprops[i]; i++) {
                                if (addlist(hdl, spaceprops[i], listp, type))
                                        return (-1);
                                listp = &(*listp)->pl_next;
                        }
                } else {
                        if (addlist(hdl, props, listp, type))
                                return (-1);
                        listp = &(*listp)->pl_next;
                }

                props = p;
                if (c == ',')
                        props++;
        }

        return (0);
}

void
zprop_free_list(zprop_list_t *pl)
{
        zprop_list_t *next;

        while (pl != NULL) {
                next = pl->pl_next;
                free(pl->pl_user_prop);
                free(pl);
                pl = next;
        }
}

typedef struct expand_data {
        zprop_list_t    **last;
        libzfs_handle_t *hdl;
        zfs_type_t type;
} expand_data_t;

int
zprop_expand_list_cb(int prop, void *cb)
{
        zprop_list_t *entry;
        expand_data_t *edp = cb;

        if ((entry = zfs_alloc(edp->hdl, sizeof (zprop_list_t))) == NULL)
                return (ZPROP_INVAL);

        entry->pl_prop = prop;
        entry->pl_width = zprop_width(prop, &entry->pl_fixed, edp->type);
        entry->pl_all = B_TRUE;

        *(edp->last) = entry;
        edp->last = &entry->pl_next;

        return (ZPROP_CONT);
}

int
zprop_expand_list(libzfs_handle_t *hdl, zprop_list_t **plp, zfs_type_t type)
{
        zprop_list_t *entry;
        zprop_list_t **last;
        expand_data_t exp;

        if (*plp == NULL) {
                /*
                 * If this is the very first time we've been called for an 'all'
                 * specification, expand the list to include all native
                 * properties.
                 */
                last = plp;

                exp.last = last;
                exp.hdl = hdl;
                exp.type = type;

                if (zprop_iter_common(zprop_expand_list_cb, &exp, B_FALSE,
                    B_FALSE, type) == ZPROP_INVAL)
                        return (-1);

                /*
                 * Add 'name' to the beginning of the list, which is handled
                 * specially.
                 */
                if ((entry = zfs_alloc(hdl, sizeof (zprop_list_t))) == NULL)
                        return (-1);

                entry->pl_prop = (type == ZFS_TYPE_POOL) ?  ZPOOL_PROP_NAME :
                    ZFS_PROP_NAME;
                entry->pl_width = zprop_width(entry->pl_prop,
                    &entry->pl_fixed, type);
                entry->pl_all = B_TRUE;
                entry->pl_next = *plp;
                *plp = entry;
        }
        return (0);
}

int
zprop_iter(zprop_func func, void *cb, boolean_t show_all, boolean_t ordered,
    zfs_type_t type)
{
        return (zprop_iter_common(func, cb, show_all, ordered, type));
}