/*
 * 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) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */


/*
 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*
 * Copyright 2016 Jason King
 * Copyright 2019 Nexenta Systems, Inc.  All rights reserved.
 */

#include <dlfcn.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <locale.h>
#include <libintl.h>
#include <stdlib.h>
#include <ftw.h>
#include <errno.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/statvfs.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <sys/mnttab.h>
#include <sys/mntent.h>
#include <sys/vfstab.h>
#include <sys/wait.h>
#include <sys/mkdev.h>
#include <sys/int_limits.h>
#include <sys/zone.h>
#include <sys/debug.h>
#include <libzfs.h>
#include <libcmdutils.h>

#include "fslib.h"

extern char *default_fstype(char *);

/*
 * General notice:
 * String pointers in this code may point to statically allocated memory
 * or dynamically allocated memory. Furthermore, a dynamically allocated
 * string may be pointed to by more than one pointer. This does not pose
 * a problem because malloc'ed memory is never free'd (so we don't need
 * to remember which pointers point to malloc'ed memory).
 */

/*
 * TRANSLATION_NOTE
 * Only strings passed as arguments to the TRANSLATE macro need to
 * be translated.
 */

#ifndef MNTTYPE_LOFS
#define MNTTYPE_LOFS            "lofs"
#endif

#define EQ(s1, s2)              (strcmp(s1, s2) == 0)
#define NEW(type)               xmalloc(sizeof (type))
#define CLEAR(var)              (void) memset(&(var), 0, sizeof (var))
#define MAX(a, b)               ((a) > (b) ? (a) : (b))
#define MAX3(a, b, c)           MAX(a, MAX(b, c))
#define TRANSLATE(s)            new_string(gettext(s))

#define MAX_OPTIONS             36
#define N_FSTYPES               20
#define MOUNT_TABLE_ENTRIES     40      /* initial allocation */
#define MSGBUF_SIZE             1024
#define LINEBUF_SIZE            256     /* either input or output lines */

#define BLOCK_SIZE              512     /* when reporting in terms of blocks */

#define DEVNM_CMD               "devnm"
#define FS_LIBPATH              "/usr/lib/fs/"
#define MOUNT_TAB               "/etc/mnttab"
#define VFS_TAB                 "/etc/vfstab"
#define REMOTE_FS               "/etc/dfs/fstypes"

#define NUL                     '\0'
#define FALSE                   0
#define TRUE                    1

/*
 * Formatting constants
 */
#define IBCS2_FILESYSTEM_WIDTH  15      /* Truncate to match ISC/SCO */
#define IBCS2_MOUNT_POINT_WIDTH 10      /* Truncate to match ISC/SCO */
#define FILESYSTEM_WIDTH        20
#define MOUNT_POINT_WIDTH       19
#define SPECIAL_DEVICE_WIDTH    18
#define FSTYPE_WIDTH            8
#define BLOCK_WIDTH             8
#define NFILES_WIDTH            8
#define KBYTE_WIDTH             11
#define AVAILABLE_WIDTH         10
#define SCALED_WIDTH            6
#define CAPACITY_WIDTH          9
#define BSIZE_WIDTH             6
#define FRAGSIZE_WIDTH          7
#define FSID_WIDTH              7
#define FLAG_WIDTH              8
#define NAMELEN_WIDTH           7
#define MNT_SPEC_WIDTH          MOUNT_POINT_WIDTH + SPECIAL_DEVICE_WIDTH + 2

/*
 * Flags for the errmsg() function
 */
#define ERR_NOFLAGS             0x0
#define ERR_NONAME              0x1     /* don't include the program name */
                                        /* as a prefix */
#define ERR_FATAL               0x2     /* call exit after printing the */
                                        /* message */
#define ERR_PERROR              0x4     /* append an errno explanation to */
                                        /* the message */
#define ERR_USAGE               0x8     /* print the usage line after the */
                                        /* message */

#define NUMBER_WIDTH            40
CTASSERT(NUMBER_WIDTH >= NN_NUMBUF_SZ);

/*
 * A numbuf_t is used when converting a number to a string representation
 */
typedef char numbuf_t[ NUMBER_WIDTH ];

/*
 * We use bool_int instead of int to make clear which variables are
 * supposed to be boolean
 */
typedef int bool_int;

struct mtab_entry {
        bool_int        mte_dev_is_valid;
        dev_t           mte_dev;
        bool_int        mte_ignore;     /* the "ignore" option was set */
        struct extmnttab        *mte_mount;
};


struct df_request {
        bool_int                dfr_valid;
        char                    *dfr_cmd_arg;   /* what the user specified */
        struct mtab_entry       *dfr_mte;
        char                    *dfr_fstype;
        int                     dfr_index;      /* to make qsort stable */
};

#define DFR_MOUNT_POINT(dfrp)   (dfrp)->dfr_mte->mte_mount->mnt_mountp
#define DFR_SPECIAL(dfrp)       (dfrp)->dfr_mte->mte_mount->mnt_special
#define DFR_FSTYPE(dfrp)        (dfrp)->dfr_mte->mte_mount->mnt_fstype
#define DFR_ISMOUNTEDFS(dfrp)   ((dfrp)->dfr_mte != NULL)

#define DFRP(p)                 ((struct df_request *)(p))

typedef void (*output_func)(struct df_request *, struct statvfs64 *);

struct df_output {
        output_func     dfo_func;       /* function that will do the output */
        int             dfo_flags;
};

/*
 * Output flags
 */
#define DFO_NOFLAGS     0x0
#define DFO_HEADER      0x1             /* output preceded by header */
#define DFO_STATVFS     0x2             /* must do a statvfs64(2) */


static char     *program_name;
static char     df_options[MAX_OPTIONS] = "-";
static size_t   df_options_len = 1;
static char     *o_option_arg;                  /* arg to the -o option */
static char     *FSType;
static char     *remote_fstypes[N_FSTYPES+1];   /* allocate an extra one */
                                                /* to use as a terminator */

/*
 * The following three variables support an in-memory copy of the mount table
 * to speedup searches.
 */
static struct mtab_entry        *mount_table;   /* array of mtab_entry's */
static size_t                   mount_table_entries;
static size_t                   mount_table_allocated_entries;

static bool_int         F_option;
static bool_int         V_option;
static bool_int         P_option;       /* Added for XCU4 compliance */
static bool_int         Z_option;
static bool_int         v_option;
static bool_int         a_option;
static bool_int         b_option;
static bool_int         e_option;
static bool_int         g_option;
static bool_int         h_option;
static bool_int         k_option;
static bool_int         l_option;
static bool_int         m_option;
static bool_int         n_option;
static bool_int         t_option;
static bool_int         o_option;

static bool_int         tty_output;
static bool_int         use_scaling;

static void usage(void);
static void do_devnm(int, char **);
static void do_df(int, char **) __NORETURN;
static void parse_options(int, char **);
static char *basename(char *);

static libzfs_handle_t *(*_libzfs_init)(void);
static zfs_handle_t *(*_zfs_open)(libzfs_handle_t *, const char *, int);
static void (*_zfs_close)(zfs_handle_t *);
static uint64_t (*_zfs_prop_get_int)(zfs_handle_t *, zfs_prop_t);
static libzfs_handle_t *g_zfs;

/*
 * Dynamically check for libzfs, in case the user hasn't installed the SUNWzfs
 * packages.  A basic utility such as df shouldn't depend on optional
 * filesystems.
 */
static boolean_t
load_libzfs(void)
{
        void *hdl;

        if (_libzfs_init != NULL)
                return (g_zfs != NULL);

        if ((hdl = dlopen("libzfs.so", RTLD_LAZY)) != NULL) {
                _libzfs_init = (libzfs_handle_t *(*)(void))dlsym(hdl,
                    "libzfs_init");
                _zfs_open = (zfs_handle_t *(*)())dlsym(hdl, "zfs_open");
                _zfs_close = (void (*)())dlsym(hdl, "zfs_close");
                _zfs_prop_get_int = (uint64_t (*)())
                    dlsym(hdl, "zfs_prop_get_int");

                if (_libzfs_init != NULL) {
                        assert(_zfs_open != NULL);
                        assert(_zfs_close != NULL);
                        assert(_zfs_prop_get_int != NULL);

                        g_zfs = _libzfs_init();
                }
        }

        return (g_zfs != NULL);
}

int
main(int argc, char *argv[])
{
        (void) setlocale(LC_ALL, "");

#if !defined(TEXT_DOMAIN)               /* Should be defined by cc -D */
#define TEXT_DOMAIN "SYS_TEST"
#endif
        (void) textdomain(TEXT_DOMAIN);

        program_name = basename(argv[0]);

        if (EQ(program_name, DEVNM_CMD))
                do_devnm(argc, argv);

        parse_options(argc, argv);

        /*
         * The k_option implies SunOS 4.x compatibility: when the special
         * device name is too long the line will be split except when the
         * output has been redirected.
         * This is also valid for the -h option.
         */

        if (use_scaling || k_option || P_option || v_option)
                tty_output = isatty(1);

        do_df(argc - optind, &argv[optind]);
        /* NOTREACHED */
}


/*
 * Prints an error message to stderr.
 */
/* VARARGS2 */
static void
errmsg(int flags, char *fmt, ...)
{
        char buf[MSGBUF_SIZE];
        va_list ap;
        int cc;
        int offset;

        if (flags & ERR_NONAME)
                offset = 0;
        else
                offset = sprintf(buf, "%s: ", program_name);

        va_start(ap, fmt);
        cc = vsprintf(&buf[offset], gettext(fmt), ap);
        offset += cc;
        va_end(ap);

        if (flags & ERR_PERROR) {
                if (buf[offset-1] != ' ')
                        (void) strcat(buf, " ");
                (void) strcat(buf, strerror(errno));
        }
        (void) fprintf(stderr, "%s\n", buf);
        if (flags & ERR_USAGE)
                usage();
        if (flags & ERR_FATAL)
                exit(1);
}


static void
usage(void)
{
        errmsg(ERR_NONAME,
            "Usage: %s [-F FSType] [-abeghklmntPVvZ]"
            " [-o FSType-specific_options]"
            " [directory | block_device | resource]", program_name);
        exit(1);
        /* NOTREACHED */
}


static char *
new_string(char *s)
{
        char *p = NULL;

        if (s) {
                p = strdup(s);
                if (p)
                        return (p);
                errmsg(ERR_FATAL, "out of memory");
                /* NOTREACHED */
        }
        return (p);
}


/*
 * Allocate memory using malloc but terminate if the allocation fails
 */
static void *
xmalloc(size_t size)
{
        void *p = malloc(size);

        if (p)
                return (p);
        errmsg(ERR_FATAL, "out of memory");
        /* NOTREACHED */
        return (NULL);
}


/*
 * Allocate memory using realloc but terminate if the allocation fails
 */
static void *
xrealloc(void *ptr, size_t size)
{
        void *p = realloc(ptr, size);

        if (p)
                return (p);
        errmsg(ERR_FATAL, "out of memory");
        /* NOTREACHED */
        return (NULL);
}


/*
 * fopen the specified file for reading but terminate if the fopen fails
 */
static FILE *
xfopen(char *file)
{
        FILE *fp = fopen(file, "r");

        if (fp == NULL)
                errmsg(ERR_FATAL + ERR_PERROR, "failed to open %s:", file);
        return (fp);
}


/*
 * Read remote file system types from REMOTE_FS into the
 * remote_fstypes array.
 */
static void
init_remote_fs(void)
{
        FILE    *fp;
        char    line_buf[LINEBUF_SIZE];
        size_t  fstype_index = 0;

        if ((fp = fopen(REMOTE_FS, "r")) == NULL) {
                errmsg(ERR_NOFLAGS,
                    "Warning: can't open %s, ignored", REMOTE_FS);
                return;
        }

        while (fgets(line_buf, sizeof (line_buf), fp) != NULL) {
                char buf[LINEBUF_SIZE];

                (void) sscanf(line_buf, "%s", buf);
                remote_fstypes[fstype_index++] = new_string(buf);

                if (fstype_index == N_FSTYPES)
                        break;
        }
        (void) fclose(fp);
}


/*
 * Returns TRUE if fstype is a remote file system type;
 * otherwise, returns FALSE.
 */
static int
is_remote_fs(char *fstype)
{
        char **p;
        static bool_int remote_fs_initialized;

        if (! remote_fs_initialized) {
                init_remote_fs();
                remote_fs_initialized = TRUE;
        }

        for (p = remote_fstypes; *p; p++)
                if (EQ(fstype, *p))
                        return (TRUE);
        return (FALSE);
}


static char *
basename(char *s)
{
        char *p = strrchr(s, '/');

        return (p ? p+1 : s);
}


/*
 * Create a new "struct extmnttab" and make sure that its fields point
 * to malloc'ed memory
 */
static struct extmnttab *
mntdup(struct extmnttab *old)
{
        struct extmnttab *new = NEW(struct extmnttab);

        new->mnt_special = new_string(old->mnt_special);
        new->mnt_mountp  = new_string(old->mnt_mountp);
        new->mnt_fstype  = new_string(old->mnt_fstype);
        new->mnt_mntopts = new_string(old->mnt_mntopts);
        new->mnt_time    = new_string(old->mnt_time);
        new->mnt_major   = old->mnt_major;
        new->mnt_minor   = old->mnt_minor;
        return (new);
}


static void
mtab_error(char *mtab_file, int status)
{
        if (status == MNT_TOOLONG)
                errmsg(ERR_NOFLAGS, "a line in %s exceeds %d characters",
                    mtab_file, MNT_LINE_MAX);
        else if (status == MNT_TOOMANY)
                errmsg(ERR_NOFLAGS,
                    "a line in %s has too many fields", mtab_file);
        else if (status == MNT_TOOFEW)
                errmsg(ERR_NOFLAGS,
                    "a line in %s has too few fields", mtab_file);
        else
                errmsg(ERR_NOFLAGS,
                    "error while reading %s: %d", mtab_file, status);
        exit(1);
        /* NOTREACHED */
}


/*
 * Read the mount table from the specified file.
 * We keep the table in memory for faster lookups.
 */
static void
mtab_read_file(void)
{
        char            *mtab_file = MOUNT_TAB;
        FILE            *fp;
        struct extmnttab        mtab;
        int             status;

        fp = xfopen(mtab_file);

        resetmnttab(fp);
        mount_table_allocated_entries = MOUNT_TABLE_ENTRIES;
        mount_table_entries = 0;
        mount_table = xmalloc(
            mount_table_allocated_entries * sizeof (struct mtab_entry));

        while ((status = getextmntent(fp, &mtab, sizeof (struct extmnttab)))
            == 0) {
                struct mtab_entry *mtep;

                if (mount_table_entries == mount_table_allocated_entries) {
                        mount_table_allocated_entries += MOUNT_TABLE_ENTRIES;
                        mount_table = xrealloc(mount_table,
                            mount_table_allocated_entries *
                            sizeof (struct mtab_entry));
                }
                mtep = &mount_table[mount_table_entries++];
                mtep->mte_mount = mntdup(&mtab);
                mtep->mte_dev_is_valid = FALSE;
                mtep->mte_ignore = (hasmntopt((struct mnttab *)&mtab,
                    MNTOPT_IGNORE) != NULL);
        }

        (void) fclose(fp);

        if (status == -1)                       /* reached EOF */
                return;
        mtab_error(mtab_file, status);
        /* NOTREACHED */
}


/*
 * We use this macro when we want to record the option for the purpose of
 * passing it to the FS-specific df
 */
#define SET_OPTION(opt)         opt##_option = TRUE, \
                                df_options[df_options_len++] = arg

static void
parse_options(int argc, char *argv[])
{
        int arg;

        opterr = 0;     /* getopt shouldn't complain about unknown options */

        while ((arg = getopt(argc, argv, "F:o:abehkVtgnlmPvZ")) != EOF) {
                if (arg == 'F') {
                        if (F_option)
                                errmsg(ERR_FATAL + ERR_USAGE,
                                    "more than one FSType specified");
                        F_option = 1;
                        FSType = optarg;
                } else if (arg == 'V' && ! V_option) {
                        V_option = TRUE;
                } else if (arg == 'v' && ! v_option) {
                        v_option = TRUE;
                } else if (arg == 'P' && ! P_option) {
                        SET_OPTION(P);
                } else if (arg == 'a' && ! a_option) {
                        SET_OPTION(a);
                } else if (arg == 'b' && ! b_option) {
                        SET_OPTION(b);
                } else if (arg == 'e' && ! e_option) {
                        SET_OPTION(e);
                } else if (arg == 'g' && ! g_option) {
                        SET_OPTION(g);
                } else if (arg == 'h') {
                        use_scaling = TRUE;
                } else if (arg == 'k' && ! k_option) {
                        SET_OPTION(k);
                } else if (arg == 'l' && ! l_option) {
                        SET_OPTION(l);
                } else if (arg == 'm' && ! m_option) {
                        SET_OPTION(m);
                } else if (arg == 'n' && ! n_option) {
                        SET_OPTION(n);
                } else if (arg == 't' && ! t_option) {
                        SET_OPTION(t);
                } else if (arg == 'o') {
                        if (o_option)
                                errmsg(ERR_FATAL + ERR_USAGE,
                                "the -o option can only be specified once");
                        o_option = TRUE;
                        o_option_arg = optarg;
                } else if (arg == 'Z') {
                        SET_OPTION(Z);
                } else if (arg == '?') {
                        errmsg(ERR_USAGE, "unknown option: %c", optopt);
                }
        }

        /*
         * Option sanity checks
         */
        if (g_option && o_option)
                errmsg(ERR_FATAL, "-o and -g options are incompatible");
        if (l_option && o_option)
                errmsg(ERR_FATAL, "-o and -l options are incompatible");
        if (n_option && o_option)
                errmsg(ERR_FATAL, "-o and -n options are incompatible");
        if (use_scaling && o_option)
                errmsg(ERR_FATAL, "-o and -h options are incompatible");
}



/*
 * Check if the user-specified argument is a resource name.
 * A resource name is whatever is placed in the mnt_special field of
 * struct mnttab. In the case of NFS, a resource name has the form
 * hostname:pathname
 * We try to find an exact match between the user-specified argument
 * and the mnt_special field of a mount table entry.
 * We also use the heuristic of removing the basename from the user-specified
 * argument and repeating the test until we get a match. This works
 * fine for NFS but may fail for other remote file system types. However,
 * it is guaranteed that the function will not fail if the user specifies
 * the exact resource name.
 * If successful, this function sets the 'dfr_mte' field of '*dfrp'
 */
static void
resource_mount_entry(struct df_request *dfrp)
{
        char *name;

        /*
         * We need our own copy since we will modify the string
         */
        name = new_string(dfrp->dfr_cmd_arg);

        for (;;) {
                char *p;
                int i;

                /*
                 * Compare against all known mount points.
                 * We start from the most recent mount, which is at the
                 * end of the array.
                 */
                for (i = mount_table_entries - 1; i >= 0; i--) {
                        struct mtab_entry *mtep = &mount_table[i];

                        if (EQ(name, mtep->mte_mount->mnt_special)) {
                                dfrp->dfr_mte = mtep;
                                break;
                        }
                }

                /*
                 * Remove the last component of the pathname.
                 * If there is no such component, this is not a resource name.
                 */
                p = strrchr(name, '/');
                if (p == NULL)
                        break;
                *p = NUL;
        }
}



/*
 * Try to match the command line argument which is a block special device
 * with the special device of one of the mounted file systems.
 * If one is found, set the appropriate field of 'dfrp' to the mount
 * table entry.
 */
static void
bdev_mount_entry(struct df_request *dfrp)
{
        int i;
        char *special = dfrp->dfr_cmd_arg;

        /*
         * Compare against all known mount points.
         * We start from the most recent mount, which is at the
         * end of the array.
         */
        for (i = mount_table_entries - 1; i >= 0; i--) {
                struct mtab_entry *mtep = &mount_table[i];

                if (EQ(special, mtep->mte_mount->mnt_special)) {
                        dfrp->dfr_mte = mtep;
                        break;
                }
        }
}

static struct mtab_entry *
devid_matches(int i, dev_t devno)
{
        struct mtab_entry       *mtep = &mount_table[i];
        struct extmnttab        *mtp = mtep->mte_mount;
        /* int  len = strlen(mtp->mnt_mountp); */

        if (EQ(mtp->mnt_fstype, MNTTYPE_SWAP))
                return (NULL);
        /*
         * check if device numbers match. If there is a cached device number
         * in the mtab_entry, use it, otherwise get the device number
         * either from the mnttab entry or by stat'ing the mount point.
         */
        if (! mtep->mte_dev_is_valid) {
                struct stat64 st;
                dev_t dev = NODEV;

                dev = makedev(mtp->mnt_major, mtp->mnt_minor);
                if (dev == 0)
                        dev = NODEV;
                if (dev == NODEV) {
                        if (stat64(mtp->mnt_mountp, &st) == -1) {
                                return (NULL);
                        } else {
                                dev = st.st_dev;
                        }
                }
                mtep->mte_dev = dev;
                mtep->mte_dev_is_valid = TRUE;
        }
        if (mtep->mte_dev == devno) {
                return (mtep);
        }
        return (NULL);
}

/*
 * Find the mount point under which the user-specified path resides
 * and set the 'dfr_mte' field of '*dfrp' to point to the mount table entry.
 */
static void
path_mount_entry(struct df_request *dfrp, dev_t devno)
{
        char                    dirpath[MAXPATHLEN];
        char                    *dir = dfrp->dfr_cmd_arg;
        struct mtab_entry       *match, *tmatch;
        int i;

        /*
         * Expand the given path to get a canonical version (i.e. an absolute
         * path without symbolic links).
         */
        if (realpath(dir, dirpath) == NULL) {
                errmsg(ERR_PERROR, "cannot canonicalize %s:", dir);
                return;
        }
        /*
         * If the mnt point is lofs, search from the top of entries from
         * /etc/mnttab and return the entry that best matches the pathname.
         * For non-lofs mount points, return the first entry from the bottom
         * of the entries in /etc/mnttab that matches on the devid field
         */
        match = NULL;
        if (dfrp->dfr_fstype && EQ(dfrp->dfr_fstype, MNTTYPE_LOFS)) {
                struct extmnttab *entryp;
                char *path, *mountp;
                char p, m;
                int score;
                int best_score = 0;
                int best_index = -1;

                for (i = 0; i < mount_table_entries; i++) {
                        entryp = mount_table[i].mte_mount;

                        if (!EQ(entryp->mnt_fstype, MNTTYPE_LOFS))
                                continue;

                        path = dirpath;
                        mountp = entryp->mnt_mountp;
                        score = 0;
                        /*
                         * Count the number of matching characters
                         * until either path or mountpoint is exhausted
                         */
                        while ((p = *path++) == (m = *mountp++)) {
                                score++;

                                if (p == '\0' || m == '\0')
                                        break;
                        }

                        /* Both exhausted so we have a match */
                        if (p == '\0' && m == '\0') {
                                best_index = i;
                                break;
                        }

                        /*
                         * We have exhausted the mountpoint and the current
                         * character in the path is a '/' hence the full path
                         * traverses this mountpoint.
                         * Record this as the best candidate so far.
                         */
                        if (p == '/' && m == '\0') {
                                if (score > best_score) {
                                        best_index = i;
                                        best_score = score;
                                }
                        }
                }

                if (best_index > -1)
                        match = &mount_table[best_index];
        } else {
                for (i = mount_table_entries - 1; i >= 0; i--) {
                        if (tmatch = devid_matches(i, devno)) {
                                /*
                                 * If executing in a zone, there might be lofs
                                 * mounts for which the real mount point is
                                 * invisible; accept the "best fit" for this
                                 * devid.
                                 */
                                match = tmatch;
                                if (!EQ(match->mte_mount->mnt_fstype,
                                    MNTTYPE_LOFS)) {
                                        break;
                                }
                        }
                }
        }
        if (! match) {
                errmsg(ERR_NOFLAGS,
                    "Could not find mount point for %s", dir);
                return;
        }
        dfrp->dfr_mte = match;
}

/*
 * Execute a single FS-specific df command for all given requests
 * Return 0 if successful, 1 otherwise.
 */
static int
run_fs_specific_df(struct df_request request_list[], int entries)
{
        int     i;
        int     argv_index;
        char    **argv;
        size_t  size;
        pid_t   pid;
        int     status;
        char    cmd_path[MAXPATHLEN];
        char    *fstype;

        if (entries == 0)
                return (0);

        fstype = request_list[0].dfr_fstype;

        if (F_option && ! EQ(FSType, fstype))
                return (0);

        (void) sprintf(cmd_path, "%s%s/df", FS_LIBPATH, fstype);
        /*
         * Argv entries:
         *              1 for the path
         *              2 for -o <options>
         *              1 for the generic options that we propagate
         *              1 for the terminating NULL pointer
         *              n for the number of user-specified arguments
         */
        size = (5 + entries) * sizeof (char *);
        argv = xmalloc(size);
        (void) memset(argv, 0, size);

        argv[0] = cmd_path;
        argv_index = 1;
        if (o_option) {
                argv[argv_index++] = "-o";
                argv[argv_index++] = o_option_arg;
        }

        /*
         * Check if we need to propagate any generic options
         */
        if (df_options_len > 1)
                argv[argv_index++] = df_options;

        /*
         * If there is a user-specified path, we pass that to the
         * FS-specific df. Otherwise, we are guaranteed to have a mount
         * point, since a request without a user path implies that
         * we are reporting only on mounted file systems.
         */
        for (i = 0; i < entries; i++) {
                struct df_request *dfrp = &request_list[i];

                argv[argv_index++] = (dfrp->dfr_cmd_arg == NULL)
                    ? DFR_MOUNT_POINT(dfrp)
                    : dfrp->dfr_cmd_arg;
        }

        if (V_option) {
                for (i = 0; i < argv_index-1; i++)
                        (void) printf("%s ", argv[i]);
                (void) printf("%s\n", argv[i]);
                return (0);
        }

        pid = fork();

        if (pid == -1) {
                errmsg(ERR_PERROR, "cannot fork process:");
                return (1);
        } else if (pid == 0) {
                (void) execv(cmd_path, argv);
                if (errno == ENOENT)
                        errmsg(ERR_NOFLAGS,
                            "operation not applicable for FSType %s",
                            fstype);
                else
                        errmsg(ERR_PERROR, "cannot execute %s:", cmd_path);
                exit(2);
        }

        /*
         * Reap the child
         */
        for (;;) {
                pid_t wpid = waitpid(pid, &status, 0);

                if (wpid == -1)
                        if (errno == EINTR)
                                continue;
                        else {
                                errmsg(ERR_PERROR, "waitpid error:");
                                return (1);
                        }
                else
                        break;
        }

        return ((WIFEXITED(status) && WEXITSTATUS(status) == 0) ? 0 : 1);
}



/*
 * Remove from the request list all requests that do not apply.
 * Notice that the subsequent processing of the requests depends on
 * the sanity checking performed by this function.
 */
static int
prune_list(struct df_request request_list[],
    size_t n_requests, size_t *valid_requests)
{
        size_t  i;
        size_t  n_valid = 0;
        int     errors = 0;

        for (i = 0; i < n_requests; i++) {
                struct df_request *dfrp = &request_list[i];

                /*
                 * Skip file systems that are not mounted if either the
                 * -l or -n options were specified. If none of these options
                 * are present, the appropriate FS-specific df will be invoked.
                 */
                if (! DFR_ISMOUNTEDFS(dfrp)) {
                        if (l_option || n_option) {
                                errmsg(ERR_NOFLAGS,
                                    "%s option incompatible with unmounted "
                                    "special device (%s)",
                                    l_option ? "-l" : "-n", dfrp->dfr_cmd_arg);
                                dfrp->dfr_valid = FALSE;
                                errors++;
                        }
                        else
                                n_valid++;
                        continue;
                }

                /*
                 * Check for inconsistency between the argument of -F and
                 * the actual file system type.
                 * If there is an inconsistency and the user specified a
                 * path, this is an error since we are asked to interpret
                 * the path using the wrong file system type. If there is
                 * no path associated with this request, we quietly ignore it.
                 */
                if (F_option && ! EQ(dfrp->dfr_fstype, FSType)) {
                        dfrp->dfr_valid = FALSE;
                        if (dfrp->dfr_cmd_arg != NULL) {
                                errmsg(ERR_NOFLAGS,
                                "Warning: %s mounted as a %s file system",
                                    dfrp->dfr_cmd_arg, dfrp->dfr_fstype);
                                errors++;
                        }
                        continue;
                }

                /*
                 * Skip remote file systems if the -l option is present
                 */
                if (l_option && is_remote_fs(dfrp->dfr_fstype)) {
                        if (dfrp->dfr_cmd_arg != NULL) {
                                errmsg(ERR_NOFLAGS,
                                    "Warning: %s is not a local file system",
                                    dfrp->dfr_cmd_arg);
                                errors++;
                        }
                        dfrp->dfr_valid = FALSE;
                        continue;
                }

                /*
                 * Skip file systems mounted as "ignore" unless the -a option
                 * is present, or the user explicitly specified them on
                 * the command line.
                 */
                if (dfrp->dfr_mte->mte_ignore &&
                    ! (a_option || dfrp->dfr_cmd_arg)) {
                        dfrp->dfr_valid = FALSE;
                        continue;
                }

                n_valid++;
        }
        *valid_requests = n_valid;
        return (errors);
}


/*
 * Print the appropriate header for the requested output format.
 * Options are checked in order of their precedence.
 */
static void
print_header(void)
{
        if (use_scaling) { /* this comes from the -h option */
                int arg = 'h';

                (void) printf("%-*s %*s %*s %*s %-*s %s\n",
                    FILESYSTEM_WIDTH, TRANSLATE("Filesystem"),
                    SCALED_WIDTH, TRANSLATE("Size"),
                    SCALED_WIDTH, TRANSLATE("Used"),
                    AVAILABLE_WIDTH, TRANSLATE("Available"),
                    CAPACITY_WIDTH, TRANSLATE("Capacity"),
                    TRANSLATE("Mounted on"));
                SET_OPTION(h);
                return;
        }
        if (k_option) {
                int arg = 'h';

                (void) printf(gettext("%-*s %*s %*s %*s %-*s %s\n"),
                    FILESYSTEM_WIDTH, TRANSLATE("Filesystem"),
                    KBYTE_WIDTH, TRANSLATE("1024-blocks"),
                    KBYTE_WIDTH, TRANSLATE("Used"),
                    KBYTE_WIDTH, TRANSLATE("Available"),
                    CAPACITY_WIDTH, TRANSLATE("Capacity"),
                    TRANSLATE("Mounted on"));
                SET_OPTION(h);
                return;
        }
        if (m_option) {
                int arg = 'h';

                (void) printf(gettext("%-*s %*s %*s %*s %-*s %s\n"),
                    FILESYSTEM_WIDTH, TRANSLATE("Filesystem"),
                    KBYTE_WIDTH, TRANSLATE("1M-blocks"),
                    KBYTE_WIDTH, TRANSLATE("Used"),
                    KBYTE_WIDTH, TRANSLATE("Available"),
                    CAPACITY_WIDTH, TRANSLATE("Capacity"),
                    TRANSLATE("Mounted on"));
                SET_OPTION(h);
                return;
        }
        /* Added for XCU4 compliance */
        if (P_option) {
                int arg = 'h';

                (void) printf(gettext("%-*s %*s %*s %*s %-*s %s\n"),
                    FILESYSTEM_WIDTH, TRANSLATE("Filesystem"),
                    KBYTE_WIDTH, TRANSLATE("512-blocks"),
                    KBYTE_WIDTH, TRANSLATE("Used"),
                    KBYTE_WIDTH, TRANSLATE("Available"),
                    CAPACITY_WIDTH, TRANSLATE("Capacity"),
                    TRANSLATE("Mounted on"));

                SET_OPTION(h);
                return;
        }
        /* End XCU4 */
        if (v_option) {
                (void) printf("%-*s %-*s %*s %*s %*s %-*s\n",
                    IBCS2_MOUNT_POINT_WIDTH, TRANSLATE("Mount Dir"),
                    IBCS2_FILESYSTEM_WIDTH, TRANSLATE("Filesystem"),
                    BLOCK_WIDTH, TRANSLATE("blocks"),
                    BLOCK_WIDTH, TRANSLATE("used"),
                    BLOCK_WIDTH, TRANSLATE("free"),
                    CAPACITY_WIDTH, TRANSLATE(" %used"));
                return;
        }
        if (e_option) {
                (void) printf(gettext("%-*s %*s\n"),
                    FILESYSTEM_WIDTH, TRANSLATE("Filesystem"),
                    BLOCK_WIDTH, TRANSLATE("ifree"));
                return;
        }
        if (b_option) {
                (void) printf(gettext("%-*s %*s\n"),
                    FILESYSTEM_WIDTH, TRANSLATE("Filesystem"),
                    BLOCK_WIDTH, TRANSLATE("avail"));
                return;
        }
}


/*
 * Convert an unsigned long long to a string representation and place the
 * result in the caller-supplied buffer.
 * The given number is in units of "unit_from" size, but the
 * converted number will be in units of "unit_to" size. The unit sizes
 * must be powers of 2.
 * The value "(unsigned long long)-1" is a special case and is always
 * converted to "-1".
 * Returns a pointer to the caller-supplied buffer.
 */
static char *
number_to_string(
                        char *buf,              /* put the result here */
                        unsigned long long number, /* convert this number */
                        int unit_from,          /* from units of this size */
                        int unit_to)            /* to units of this size */
{
        if ((long long)number == (long long)-1) {
                (void) strcpy(buf, "-1");
                return (buf);
        }

        /* don't crash if, i.e. fsp->f_frsize == 0 */
        if (unit_from <= 0)
                unit_from = 1;
        if (unit_to <= 0)
                unit_to = 1;

        if (unit_from == unit_to)
                (void) sprintf(buf, "%llu", number);
        else if (unit_from < unit_to)
                (void) sprintf(buf, "%llu",
                    number / (unsigned long long)(unit_to / unit_from));
        else
                (void) sprintf(buf, "%llu",
                    number * (unsigned long long)(unit_from / unit_to));

        return (buf);
}

/*
 * The statvfs() implementation allows us to return only two values, the total
 * number of blocks and the number of blocks free.  The equation 'used = total -
 * free' will not work for ZFS filesystems, due to the nature of pooled storage.
 * We choose to return values in the statvfs structure that will produce correct
 * results for 'used' and 'available', but not 'total'.  This function will open
 * the underlying ZFS dataset if necessary and get the real value.
 */
static void
adjust_total_blocks(struct df_request *dfrp, fsblkcnt64_t *total,
    uint64_t blocksize)
{
        char *dataset, *slash;
        boolean_t first = TRUE;
        uint64_t quota = 0;

        if (strcmp(DFR_FSTYPE(dfrp), MNTTYPE_ZFS) != 0 || !load_libzfs())
                return;

        /*
         * We want to get the total size for this filesystem as bounded by any
         * quotas. In order to do this, we start at the current filesystem and
         * work upwards looking for the smallest quota.  When we reach the
         * pool itself, the quota is the amount used plus the amount
         * available.
         */
        if ((dataset = strdup(DFR_SPECIAL(dfrp))) == NULL)
                return;

        slash = dataset + strlen(dataset);
        while (slash != NULL) {
                zfs_handle_t *zhp;
                uint64_t this_quota;

                *slash = '\0';

                zhp = _zfs_open(g_zfs, dataset, ZFS_TYPE_DATASET);
                if (zhp == NULL)
                        break;

                /* true at first iteration of loop */
                if (first) {
                        quota = _zfs_prop_get_int(zhp, ZFS_PROP_REFQUOTA);
                        if (quota == 0)
                                quota = UINT64_MAX;
                        first = FALSE;
                }

                this_quota = _zfs_prop_get_int(zhp, ZFS_PROP_QUOTA);
                if (this_quota && this_quota < quota)
                        quota = this_quota;

                /* true at last iteration of loop */
                if ((slash = strrchr(dataset, '/')) == NULL) {
                        uint64_t size;

                        size = _zfs_prop_get_int(zhp, ZFS_PROP_USED) +
                            _zfs_prop_get_int(zhp, ZFS_PROP_AVAILABLE);
                        if (size < quota)
                                quota = size;
                }

                _zfs_close(zhp);
        }

        /*
         * Modify total only if we managed to get some stats from libzfs.
         */
        if (quota != 0)
                *total = quota / blocksize;
        free(dataset);
}

/*
 * The output will appear properly columnized regardless of the names of
 * the various fields
 */
static void
g_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        fsblkcnt64_t    available_blocks        = fsp->f_bavail;
        fsblkcnt64_t    total_blocks = fsp->f_blocks;
        numbuf_t        total_blocks_buf;
        numbuf_t        total_files_buf;
        numbuf_t        free_blocks_buf;
        numbuf_t        available_blocks_buf;
        numbuf_t        free_files_buf;
        numbuf_t        fname_buf;
        char            *temp_buf;

#define DEFINE_STR_LEN(var)                     \
        static char *var##_str;                 \
        static size_t var##_len

#define SET_STR_LEN(name, var)\
        if (! var##_str) {\
                var##_str = TRANSLATE(name); \
                var##_len = strlen(var##_str); \
        }

        DEFINE_STR_LEN(block_size);
        DEFINE_STR_LEN(frag_size);
        DEFINE_STR_LEN(total_blocks);
        DEFINE_STR_LEN(free_blocks);
        DEFINE_STR_LEN(available);
        DEFINE_STR_LEN(total_files);
        DEFINE_STR_LEN(free_files);
        DEFINE_STR_LEN(fstype);
        DEFINE_STR_LEN(fsys_id);
        DEFINE_STR_LEN(fname);
        DEFINE_STR_LEN(flag);

        /*
         * TRANSLATION_NOTE
         * The first argument of each of the following macro invocations is a
         * string that needs to be translated.
         */
        SET_STR_LEN("block size", block_size);
        SET_STR_LEN("frag size", frag_size);
        SET_STR_LEN("total blocks", total_blocks);
        SET_STR_LEN("free blocks", free_blocks);
        SET_STR_LEN("available", available);
        SET_STR_LEN("total files", total_files);
        SET_STR_LEN("free files", free_files);
        SET_STR_LEN("fstype", fstype);
        SET_STR_LEN("filesys id", fsys_id);
        SET_STR_LEN("filename length", fname);
        SET_STR_LEN("flag", flag);

#define NCOL1_WIDTH     (int)MAX3(BLOCK_WIDTH, NFILES_WIDTH, FSTYPE_WIDTH)
#define NCOL2_WIDTH     (int)MAX3(BLOCK_WIDTH, FSID_WIDTH, FLAG_WIDTH) + 2
#define NCOL3_WIDTH     (int)MAX3(BSIZE_WIDTH, BLOCK_WIDTH, NAMELEN_WIDTH)
#define NCOL4_WIDTH     (int)MAX(FRAGSIZE_WIDTH, NFILES_WIDTH)

#define SCOL1_WIDTH     (int)MAX3(total_blocks_len, free_files_len, fstype_len)
#define SCOL2_WIDTH     (int)MAX3(free_blocks_len, fsys_id_len, flag_len)
#define SCOL3_WIDTH     (int)MAX3(block_size_len, available_len, fname_len)
#define SCOL4_WIDTH     (int)MAX(frag_size_len, total_files_len)

        temp_buf = xmalloc(
            MAX(MOUNT_POINT_WIDTH, strlen(DFR_MOUNT_POINT(dfrp)))
            + MAX(SPECIAL_DEVICE_WIDTH, strlen(DFR_SPECIAL(dfrp)))
            + 20); /* plus slop - nulls & formatting */
        (void) sprintf(temp_buf, "%-*s(%-*s):",
            MOUNT_POINT_WIDTH, DFR_MOUNT_POINT(dfrp),
            SPECIAL_DEVICE_WIDTH, DFR_SPECIAL(dfrp));

        (void) printf("%-*s %*lu %-*s %*lu %-*s\n",
            NCOL1_WIDTH + 1 + SCOL1_WIDTH + 1 + NCOL2_WIDTH + 1 +  SCOL2_WIDTH,
            temp_buf,
            NCOL3_WIDTH, fsp->f_bsize, SCOL3_WIDTH, block_size_str,
            NCOL4_WIDTH, fsp->f_frsize, SCOL4_WIDTH, frag_size_str);
        free(temp_buf);

        /*
         * Adjust available_blocks value -  it can be less than 0 on
         * a 4.x file system. Reset it to 0 in order to avoid printing
         * negative numbers.
         */
        if ((long long)available_blocks < (long long)0)
                available_blocks = (fsblkcnt64_t)0;

        adjust_total_blocks(dfrp, &total_blocks, fsp->f_frsize);

        (void) printf("%*s %-*s %*s %-*s %*s %-*s %*s %-*s\n",
            NCOL1_WIDTH, number_to_string(total_blocks_buf,
            total_blocks, fsp->f_frsize, 512),
            SCOL1_WIDTH, total_blocks_str,
            NCOL2_WIDTH, number_to_string(free_blocks_buf,
            fsp->f_bfree, fsp->f_frsize, 512),
            SCOL2_WIDTH, free_blocks_str,
            NCOL3_WIDTH, number_to_string(available_blocks_buf,
            available_blocks, fsp->f_frsize, 512),
            SCOL3_WIDTH, available_str,
            NCOL4_WIDTH, number_to_string(total_files_buf,
            fsp->f_files, 1, 1),
            SCOL4_WIDTH, total_files_str);

        (void) printf("%*s %-*s %*lu %-*s %s\n",
            NCOL1_WIDTH, number_to_string(free_files_buf,
            fsp->f_ffree, 1, 1),
            SCOL1_WIDTH, free_files_str,
            NCOL2_WIDTH, fsp->f_fsid, SCOL2_WIDTH, fsys_id_str,
            fsp->f_fstr);

        (void) printf("%*s %-*s %#*.*lx %-*s %*s %-*s\n\n",
            NCOL1_WIDTH, fsp->f_basetype, SCOL1_WIDTH, fstype_str,
            NCOL2_WIDTH, NCOL2_WIDTH-2, fsp->f_flag, SCOL2_WIDTH, flag_str,
            NCOL3_WIDTH, number_to_string(fname_buf,
            (unsigned long long)fsp->f_namemax, 1, 1),
            SCOL3_WIDTH, fname_str);
}


static void
k_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        fsblkcnt64_t total_blocks               = fsp->f_blocks;
        fsblkcnt64_t    free_blocks             = fsp->f_bfree;
        fsblkcnt64_t    available_blocks        = fsp->f_bavail;
        fsblkcnt64_t    used_blocks;
        char            *file_system            = DFR_SPECIAL(dfrp);
        numbuf_t        total_blocks_buf;
        numbuf_t        used_blocks_buf;
        numbuf_t        available_blocks_buf;
        char            capacity_buf[LINEBUF_SIZE];

        /*
         * If the free block count is -1, don't trust anything but the total
         * number of blocks.
         */
        if (free_blocks == (fsblkcnt64_t)-1) {
                used_blocks = (fsblkcnt64_t)-1;
                (void) strcpy(capacity_buf, "  100%");
        } else {
                fsblkcnt64_t reserved_blocks = free_blocks - available_blocks;

                used_blocks     = total_blocks - free_blocks;

                /*
                 * The capacity estimation is bogus when available_blocks is 0
                 * and the super-user has allocated more space. The reason
                 * is that reserved_blocks is inaccurate in that case, because
                 * when the super-user allocates space, free_blocks is updated
                 * but available_blocks is not (since it can't drop below 0).
                 *
                 * XCU4 and POSIX.2 require that any fractional result of the
                 * capacity estimation be rounded to the next highest integer,
                 * hence the addition of 0.5.
                 */
                (void) sprintf(capacity_buf, "%5.0f%%",
                    (total_blocks == 0) ? 0.0 :
                    ((double)used_blocks /
                    (double)(total_blocks - reserved_blocks))
                    * 100.0 + 0.5);
        }

        /*
         * The available_blocks can be less than 0 on a 4.x file system.
         * Reset it to 0 in order to avoid printing negative numbers.
         */
        if ((long long)available_blocks < (long long)0)
                available_blocks = (fsblkcnt64_t)0;
        /*
         * Print long special device names (usually NFS mounts) in a line
         * by themselves when the output is directed to a terminal.
         */
        if (tty_output && strlen(file_system) > (size_t)FILESYSTEM_WIDTH) {
                (void) printf("%s\n", file_system);
                file_system = "";
        }

        adjust_total_blocks(dfrp, &total_blocks, fsp->f_frsize);

        if (use_scaling) { /* comes from the -h option */
                nicenum_scale(total_blocks, fsp->f_frsize,
                    total_blocks_buf, sizeof (total_blocks_buf), 0);
                nicenum_scale(used_blocks, fsp->f_frsize,
                    used_blocks_buf, sizeof (used_blocks_buf), 0);
                nicenum_scale(available_blocks, fsp->f_frsize,
                    available_blocks_buf, sizeof (available_blocks_buf), 0);

                (void) printf("%-*s %*s %*s %*s %-*s %-s\n",
                    FILESYSTEM_WIDTH, file_system,
                    SCALED_WIDTH, total_blocks_buf,
                    SCALED_WIDTH, used_blocks_buf,
                    AVAILABLE_WIDTH, available_blocks_buf,
                    CAPACITY_WIDTH, capacity_buf, DFR_MOUNT_POINT(dfrp));
                return;
        }

        if (v_option) {
        (void) printf("%-*.*s %-*.*s %*lld %*lld %*lld %-.*s\n",
            IBCS2_MOUNT_POINT_WIDTH, IBCS2_MOUNT_POINT_WIDTH,
            DFR_MOUNT_POINT(dfrp),
            IBCS2_FILESYSTEM_WIDTH, IBCS2_FILESYSTEM_WIDTH, file_system,
            BLOCK_WIDTH, total_blocks,
            BLOCK_WIDTH, used_blocks,
            BLOCK_WIDTH, available_blocks,
            CAPACITY_WIDTH,     capacity_buf);
                return;
        }

        if (P_option && !k_option && !m_option) {
        (void) printf("%-*s %*s %*s %*s %-*s %-s\n",
            FILESYSTEM_WIDTH, file_system,
            KBYTE_WIDTH, number_to_string(total_blocks_buf,
            total_blocks, fsp->f_frsize, 512),
            KBYTE_WIDTH, number_to_string(used_blocks_buf,
            used_blocks, fsp->f_frsize, 512),
            KBYTE_WIDTH, number_to_string(available_blocks_buf,
            available_blocks, fsp->f_frsize, 512),
            CAPACITY_WIDTH, capacity_buf,
            DFR_MOUNT_POINT(dfrp));
        } else if (m_option) {
        (void) printf("%-*s %*s %*s %*s %-*s %-s\n",
            FILESYSTEM_WIDTH, file_system,
            KBYTE_WIDTH, number_to_string(total_blocks_buf,
            total_blocks, fsp->f_frsize, 1024*1024),
            KBYTE_WIDTH, number_to_string(used_blocks_buf,
            used_blocks, fsp->f_frsize, 1024*1024),
            KBYTE_WIDTH, number_to_string(available_blocks_buf,
            available_blocks, fsp->f_frsize, 1024*1024),
            CAPACITY_WIDTH,     capacity_buf,
            DFR_MOUNT_POINT(dfrp));
        } else {
        (void) printf("%-*s %*s %*s %*s %-*s %-s\n",
            FILESYSTEM_WIDTH, file_system,
            KBYTE_WIDTH, number_to_string(total_blocks_buf,
            total_blocks, fsp->f_frsize, 1024),
            KBYTE_WIDTH, number_to_string(used_blocks_buf,
            used_blocks, fsp->f_frsize, 1024),
            KBYTE_WIDTH, number_to_string(available_blocks_buf,
            available_blocks, fsp->f_frsize, 1024),
            CAPACITY_WIDTH,     capacity_buf,
            DFR_MOUNT_POINT(dfrp));
        }
}

/*
 * The following is for internationalization support.
 */
static bool_int strings_initialized;
static char     *files_str;
static char     *blocks_str;
static char     *total_str;
static char     *kilobytes_str;

static void
strings_init(void)
{
        total_str = TRANSLATE("total");
        files_str = TRANSLATE("files");
        blocks_str = TRANSLATE("blocks");
        kilobytes_str = TRANSLATE("kilobytes");
        strings_initialized = TRUE;
}

#define STRINGS_INIT()          if (!strings_initialized) strings_init()


static void
t_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        fsblkcnt64_t    total_blocks = fsp->f_blocks;
        numbuf_t        total_blocks_buf;
        numbuf_t        total_files_buf;
        numbuf_t        free_blocks_buf;
        numbuf_t        free_files_buf;

        STRINGS_INIT();

        adjust_total_blocks(dfrp, &total_blocks, fsp->f_frsize);

        (void) printf("%-*s(%-*s): %*s %s %*s %s\n",
            MOUNT_POINT_WIDTH, DFR_MOUNT_POINT(dfrp),
            SPECIAL_DEVICE_WIDTH, DFR_SPECIAL(dfrp),
            BLOCK_WIDTH, number_to_string(free_blocks_buf,
            fsp->f_bfree, fsp->f_frsize, 512),
            blocks_str,
            NFILES_WIDTH, number_to_string(free_files_buf,
            fsp->f_ffree, 1, 1),
            files_str);
        /*
         * The total column used to use the same space as the mnt pt & special
         * dev fields. However, this doesn't work with massive special dev
         * fields * (eg > 500 chars) causing an enormous amount of white space
         * before the total column (see bug 4100411). So the code was
         * simplified to set the total column at the usual gap.
         * This had the side effect of fixing a bug where the previously
         * used static buffer was overflowed by the same massive special dev.
         */
        (void) printf("%*s: %*s %s %*s %s\n",
            MNT_SPEC_WIDTH, total_str,
            BLOCK_WIDTH, number_to_string(total_blocks_buf,
            total_blocks, fsp->f_frsize, 512),
            blocks_str,
            NFILES_WIDTH, number_to_string(total_files_buf,
            fsp->f_files, 1, 1),
            files_str);
}


static void
eb_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        numbuf_t free_files_buf;
        numbuf_t free_kbytes_buf;

        STRINGS_INIT();

        (void) printf("%-*s(%-*s): %*s %s\n",
            MOUNT_POINT_WIDTH, DFR_MOUNT_POINT(dfrp),
            SPECIAL_DEVICE_WIDTH, DFR_SPECIAL(dfrp),
            MAX(KBYTE_WIDTH, NFILES_WIDTH),
            number_to_string(free_kbytes_buf,
            fsp->f_bfree, fsp->f_frsize, 1024),
            kilobytes_str);
        (void) printf("%-*s(%-*s): %*s %s\n",
            MOUNT_POINT_WIDTH, DFR_MOUNT_POINT(dfrp),
            SPECIAL_DEVICE_WIDTH, DFR_SPECIAL(dfrp),
            MAX(NFILES_WIDTH, NFILES_WIDTH),
            number_to_string(free_files_buf, fsp->f_ffree, 1, 1),
            files_str);
}


static void
e_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        numbuf_t free_files_buf;

        (void) printf("%-*s %*s\n",
            FILESYSTEM_WIDTH, DFR_SPECIAL(dfrp),
            NFILES_WIDTH,
            number_to_string(free_files_buf, fsp->f_ffree, 1, 1));
}


static void
b_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        numbuf_t free_blocks_buf;

        (void) printf("%-*s %*s\n",
            FILESYSTEM_WIDTH, DFR_SPECIAL(dfrp),
            BLOCK_WIDTH, number_to_string(free_blocks_buf,
            fsp->f_bfree, fsp->f_frsize, 1024));
}


/* ARGSUSED */
static void
n_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        (void) printf("%-*s: %-*s\n",
            MOUNT_POINT_WIDTH, DFR_MOUNT_POINT(dfrp),
            FSTYPE_WIDTH, dfrp->dfr_fstype);
}


static void
default_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        numbuf_t free_blocks_buf;
        numbuf_t free_files_buf;

        STRINGS_INIT();

        (void) printf("%-*s(%-*s):%*s %s %*s %s\n",
            MOUNT_POINT_WIDTH, DFR_MOUNT_POINT(dfrp),
            SPECIAL_DEVICE_WIDTH, DFR_SPECIAL(dfrp),
            BLOCK_WIDTH, number_to_string(free_blocks_buf,
            fsp->f_bfree, fsp->f_frsize, 512),
            blocks_str,
            NFILES_WIDTH, number_to_string(free_files_buf,
            fsp->f_ffree, 1, 1),
            files_str);
}


/* ARGSUSED */
static void
V_output(struct df_request *dfrp, struct statvfs64 *fsp)
{
        char temp_buf[LINEBUF_SIZE];

        if (df_options_len > 1)
                (void) strcat(strcpy(temp_buf, df_options), " ");
        else
                temp_buf[0] = NUL;

        (void) printf("%s -F %s %s%s\n",
            program_name, dfrp->dfr_fstype, temp_buf,
            dfrp->dfr_cmd_arg ? dfrp->dfr_cmd_arg: DFR_SPECIAL(dfrp));
}


/*
 * This function is used to sort the array of df_requests according to fstype
 */
static int
df_reqcomp(const void *p1, const void *p2)
{
        int v = strcmp(DFRP(p1)->dfr_fstype, DFRP(p2)->dfr_fstype);

        if (v != 0)
                return (v);
        else
                return (DFRP(p1)->dfr_index - DFRP(p2)->dfr_index);
}


static void
vfs_error(char *file, int status)
{
        if (status == VFS_TOOLONG)
                errmsg(ERR_NOFLAGS, "a line in %s exceeds %d characters",
                    file, MNT_LINE_MAX);
        else if (status == VFS_TOOMANY)
                errmsg(ERR_NOFLAGS, "a line in %s has too many fields", file);
        else if (status == VFS_TOOFEW)
                errmsg(ERR_NOFLAGS, "a line in %s has too few fields", file);
        else
                errmsg(ERR_NOFLAGS, "error while reading %s: %d", file, status);
}


/*
 * Try to determine the fstype for the specified block device.
 * Return in order of decreasing preference:
 *      file system type from vfstab
 *      file system type as specified by -F option
 *      default file system type
 */
static char *
find_fstype(char *special)
{
        struct vfstab   vtab;
        FILE            *fp;
        int             status;
        char            *vfstab_file = VFS_TAB;

        fp = xfopen(vfstab_file);
        status = getvfsspec(fp, &vtab, special);
        (void) fclose(fp);
        if (status > 0)
                vfs_error(vfstab_file, status);

        if (status == 0) {
                if (F_option && ! EQ(FSType, vtab.vfs_fstype))
                        errmsg(ERR_NOFLAGS,
                        "warning: %s is of type %s", special, vtab.vfs_fstype);
                return (new_string(vtab.vfs_fstype));
        }
        else
                return (F_option ? FSType : default_fstype(special));
}

/*
 * When this function returns, the following fields are filled for all
 * valid entries in the requests[] array:
 *              dfr_mte         (if the file system is mounted)
 *              dfr_fstype
 *              dfr_index
 *
 * The function returns the number of errors that occurred while building
 * the request list.
 */
static int
create_request_list(
                        int argc,
                        char *argv[],
                        struct df_request *requests_p[],
                        size_t *request_count)
{
        struct df_request       *requests;
        struct df_request       *dfrp;
        size_t                  size;
        size_t                  i;
        size_t                  request_index = 0;
        size_t                  max_requests;
        int                     errors = 0;

        /*
         * If no args, use the mounted file systems, otherwise use the
         * user-specified arguments.
         */
        if (argc == 0) {
                mtab_read_file();
                max_requests = mount_table_entries;
        } else
                max_requests = argc;

        size = max_requests * sizeof (struct df_request);
        requests = xmalloc(size);
        (void) memset(requests, 0, size);

        if (argc == 0) {
                /*
                 * If -Z wasn't specified, we skip mounts in other
                 * zones.  This obviously is a noop in a non-global
                 * zone.
                 */
                boolean_t showall = (getzoneid() != GLOBAL_ZONEID) || Z_option;
                struct zone_summary *zsp;

                if (!showall) {
                        zsp = fs_get_zone_summaries();
                        if (zsp == NULL)
                                errmsg(ERR_FATAL,
                                    "unable to retrieve list of zones");
                }

                for (i = 0; i < mount_table_entries; i++) {
                        struct extmnttab *mtp = mount_table[i].mte_mount;

                        if (EQ(mtp->mnt_fstype, MNTTYPE_SWAP))
                                continue;

                        if (!showall) {
                                if (fs_mount_in_other_zone(zsp,
                                    mtp->mnt_mountp))
                                        continue;
                        }
                        dfrp = &requests[request_index++];
                        dfrp->dfr_mte           = &mount_table[i];
                        dfrp->dfr_fstype        = mtp->mnt_fstype;
                        dfrp->dfr_index         = i;
                        dfrp->dfr_valid         = TRUE;
                }
        } else {
                struct stat64 *arg_stat; /* array of stat structures    */
                bool_int *valid_stat;   /* which structures are valid   */

                arg_stat = xmalloc(argc * sizeof (struct stat64));
                valid_stat = xmalloc(argc * sizeof (bool_int));

                /*
                 * Obtain stat64 information for each argument before
                 * constructing the list of mounted file systems. By
                 * touching all these places we force the automounter
                 * to establish any mounts required to access the arguments,
                 * so that the corresponding mount table entries will exist
                 * when we look for them.
                 * It is still possible that the automounter may timeout
                 * mounts between the time we read the mount table and the
                 * time we process the request. Even in that case, when
                 * we issue the statvfs64(2) for the mount point, the file
                 * system will be mounted again. The only problem will
                 * occur if the automounter maps change in the meantime
                 * and the mount point is eliminated.
                 */
                for (i = 0; i < argc; i++)
                        valid_stat[i] = (stat64(argv[i], &arg_stat[i]) == 0);

                mtab_read_file();

                for (i = 0; i < argc; i++) {
                        char *arg = argv[i];

                        dfrp = &requests[request_index];

                        dfrp->dfr_index = request_index;
                        dfrp->dfr_cmd_arg = arg;

                        if (valid_stat[i]) {
                                dfrp->dfr_fstype = arg_stat[i].st_fstype;
                                if (S_ISBLK(arg_stat[i].st_mode)) {
                                        bdev_mount_entry(dfrp);
                                        dfrp->dfr_valid = TRUE;
                                } else if (S_ISDIR(arg_stat[i].st_mode) ||
                                    S_ISREG(arg_stat[i].st_mode) ||
                                    S_ISFIFO(arg_stat[i].st_mode)) {
                                        path_mount_entry(dfrp,
                                            arg_stat[i].st_dev);
                                        if (! DFR_ISMOUNTEDFS(dfrp)) {
                                                errors++;
                                                continue;
                                        }
                                        dfrp->dfr_valid = TRUE;
                                }
                        } else {
                                resource_mount_entry(dfrp);
                                dfrp->dfr_valid = DFR_ISMOUNTEDFS(dfrp);
                        }

                        /*
                         * If we haven't managed to verify that the request
                         * is valid, we must have gotten a bad argument.
                         */
                        if (!dfrp->dfr_valid) {
                                errmsg(ERR_NOFLAGS,
                                    "(%-10s) not a block device, directory or "
                                    "mounted resource", arg);
                                errors++;
                                continue;
                        }

                        /*
                         * Determine the file system type.
                         */
                        if (DFR_ISMOUNTEDFS(dfrp))
                                dfrp->dfr_fstype =
                                    dfrp->dfr_mte->mte_mount->mnt_fstype;
                        else
                                dfrp->dfr_fstype =
                                    find_fstype(dfrp->dfr_cmd_arg);

                        request_index++;
                }
        }
        *requests_p = requests;
        *request_count = request_index;
        return (errors);
}


/*
 * Select the appropriate function and flags to use for output.
 * Notice that using both -e and -b options produces a different form of
 * output than either of those two options alone; this is the behavior of
 * the SVR4 df.
 */
static struct df_output *
select_output(void)
{
        static struct df_output dfo;

        /*
         * The order of checking options follows the option precedence
         * rules as they are listed in the man page.
         */
        if (use_scaling) { /* comes from the -h option */
                dfo.dfo_func = k_output;
                dfo.dfo_flags = DFO_HEADER + DFO_STATVFS;
        } else if (V_option) {
                dfo.dfo_func = V_output;
                dfo.dfo_flags = DFO_NOFLAGS;
        } else if (g_option) {
                dfo.dfo_func = g_output;
                dfo.dfo_flags = DFO_STATVFS;
        } else if (k_option || m_option || P_option || v_option) {
                dfo.dfo_func = k_output;
                dfo.dfo_flags = DFO_HEADER + DFO_STATVFS;
        } else if (t_option) {
                dfo.dfo_func = t_output;
                dfo.dfo_flags = DFO_STATVFS;
        } else if (b_option && e_option) {
                dfo.dfo_func = eb_output;
                dfo.dfo_flags = DFO_STATVFS;
        } else if (b_option) {
                dfo.dfo_func = b_output;
                dfo.dfo_flags = DFO_HEADER + DFO_STATVFS;
        } else if (e_option) {
                dfo.dfo_func = e_output;
                dfo.dfo_flags = DFO_HEADER + DFO_STATVFS;
        } else if (n_option) {
                dfo.dfo_func = n_output;
                dfo.dfo_flags = DFO_NOFLAGS;
        } else {
                dfo.dfo_func = default_output;
                dfo.dfo_flags = DFO_STATVFS;
        }
        return (&dfo);
}


/*
 * The (argc,argv) pair contains all the non-option arguments
 */
static void
do_df(int argc, char *argv[])
{
        size_t                  i;
        struct df_request       *requests;              /* array of requests */
        size_t                  n_requests;
        struct df_request       *dfrp;
        int                     errors;

        errors = create_request_list(argc, argv, &requests, &n_requests);

        if (n_requests == 0)
                exit(errors);

        /*
         * If we are going to run the FSType-specific df command,
         * rearrange the requests so that we can issue a single command
         * per file system type.
         */
        if (o_option) {
                size_t j;

                /*
                 * qsort is not a stable sorting method (i.e. requests of
                 * the same file system type may be swapped, and hence appear
                 * in the output in a different order from the one in which
                 * they were listed in the command line). In order to force
                 * stability, we use the dfr_index field which is unique
                 * for each request.
                 */
                qsort(requests,
                    n_requests, sizeof (struct df_request), df_reqcomp);
                for (i = 0; i < n_requests; i = j) {
                        char *fstype = requests[i].dfr_fstype;

                        for (j = i+1; j < n_requests; j++)
                                if (! EQ(fstype, requests[j].dfr_fstype))
                                        break;

                        /*
                         * At this point, requests in the range [i,j) are
                         * of the same type.
                         *
                         * If the -F option was used, and the user specified
                         * arguments, the filesystem types must match
                         *
                         * XXX: the alternative of doing this check here is to
                         *      invoke prune_list, but then we have to
                         *      modify this code to ignore invalid requests.
                         */
                        if (F_option && ! EQ(fstype, FSType)) {
                                size_t k;

                                for (k = i; k < j; k++) {
                                        dfrp = &requests[k];
                                        if (dfrp->dfr_cmd_arg != NULL) {
                                                errmsg(ERR_NOFLAGS,
                                                    "Warning: %s mounted as a "
                                                    "%s file system",
                                                    dfrp->dfr_cmd_arg,
                                                    dfrp->dfr_fstype);
                                                errors++;
                                        }
                                }
                        } else
                                errors += run_fs_specific_df(&requests[i], j-i);
                }
        } else {
                size_t valid_requests;

                /*
                 * We have to prune the request list to avoid printing a header
                 * if there are no valid requests
                 */
                errors += prune_list(requests, n_requests, &valid_requests);

                if (valid_requests) {
                        struct df_output *dfop = select_output();

                        /* indicates if we already printed out a header line */
                        int printed_header = 0;

                        for (i = 0; i < n_requests; i++) {
                                dfrp = &requests[i];
                                if (! dfrp->dfr_valid)
                                        continue;

                                /*
                                 * If we don't have a mount point,
                                 * this must be a block device.
                                 */
                                if (DFR_ISMOUNTEDFS(dfrp)) {
                                        struct statvfs64 stvfs;

                                        if ((dfop->dfo_flags & DFO_STATVFS) &&
                                            statvfs64(DFR_MOUNT_POINT(dfrp),
                                            &stvfs) == -1) {
                                                errmsg(ERR_PERROR,
                                                    "cannot statvfs %s:",
                                                    DFR_MOUNT_POINT(dfrp));
                                                errors++;
                                                continue;
                                        }
                                        if ((!printed_header) &&
                                            (dfop->dfo_flags & DFO_HEADER)) {
                                                print_header();
                                                printed_header = 1;
                                        }

                                        (*dfop->dfo_func)(dfrp, &stvfs);
                                } else {
                                        /*
                                         *  -h option only works for
                                         *  mounted filesystems
                                         */
                                        if (use_scaling) {
                                                errmsg(ERR_NOFLAGS,
                "-h option incompatible with unmounted special device (%s)",
                                                    dfrp->dfr_cmd_arg);
                                                errors++;
                                                continue;
                                        }
                                        errors += run_fs_specific_df(dfrp, 1);
                                }
                        }
                }
        }
        exit(errors);
}


/*
 * The rest of this file implements the devnm command
 */

static char *
find_dev_name(char *file, dev_t dev)
{
        struct df_request dfreq;

        dfreq.dfr_cmd_arg = file;
        dfreq.dfr_fstype = 0;
        dfreq.dfr_mte = NULL;
        path_mount_entry(&dfreq, dev);
        return (DFR_ISMOUNTEDFS(&dfreq) ? DFR_SPECIAL(&dfreq) : NULL);
}


static void
do_devnm(int argc, char *argv[])
{
        int arg;
        int errors = 0;
        char *dev_name;

        if (argc == 1)
                errmsg(ERR_NONAME, "Usage: %s name ...", DEVNM_CMD);

        mtab_read_file();

        for (arg = 1; arg < argc; arg++) {
                char *file = argv[arg];
                struct stat64 st;

                if (stat64(file, &st) == -1) {
                        errmsg(ERR_PERROR, "%s: ", file);
                        errors++;
                        continue;
                }

                if (! is_remote_fs(st.st_fstype) &&
                    ! EQ(st.st_fstype, MNTTYPE_TMPFS) &&
                    (dev_name = find_dev_name(file, st.st_dev)))
                        (void) printf("%s %s\n", dev_name, file);
                else
                        errmsg(ERR_NOFLAGS,
                            "%s not found", file);
        }
        exit(errors);
        /* NOTREACHED */
}