source: MondoRescue/branches/3.2/mindi-busybox/coreutils/df.c@ 3263

/* vi: set sw=4 ts=4: */
/*
 * Mini df implementation for busybox
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 * based on original code by (I think) Bruce Perens <bruce@pixar.com>.
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

/* BB_AUDIT SUSv3 _NOT_ compliant -- option -t missing. */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/df.html */

/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
 *
 * Size reduction.  Removed floating point dependency.  Added error checking
 * on output.  Output stats on 0-sized filesystems if specifically listed on
 * the command line.  Properly round *-blocks, Used, and Available quantities.
 *
 * Aug 28, 2008      Bernhard Reutner-Fischer
 *
 * Implement -P and -B; better coreutils compat; cleanup
 */

//usage:#define df_trivial_usage
//usage:    "[-Pk"
//usage:    IF_FEATURE_HUMAN_READABLE("mh")
//usage:    IF_FEATURE_DF_FANCY("ai] [-B SIZE")
//usage:    "] [FILESYSTEM]..."
//usage:#define df_full_usage "\n\n"
//usage:       "Print filesystem usage statistics\n"
//usage:     "\n    -P  POSIX output format"
//usage:     "\n    -k  1024-byte blocks (default)"
//usage:    IF_FEATURE_HUMAN_READABLE(
//usage:     "\n    -m  1M-byte blocks"
//usage:     "\n    -h  Human readable (e.g. 1K 243M 2G)"
//usage:    )
//usage:    IF_FEATURE_DF_FANCY(
//usage:     "\n    -a  Show all filesystems"
//usage:     "\n    -i  Inodes"
//usage:     "\n    -B SIZE Blocksize"
//usage:    )
//usage:
//usage:#define df_example_usage
//usage:       "$ df\n"
//usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
//usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
//usage:       "/dev/sda1                64216     36364     27852  57% /boot\n"
//usage:       "$ df /dev/sda3\n"
//usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
//usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
//usage:       "$ POSIXLY_CORRECT=sure df /dev/sda3\n"
//usage:       "Filesystem         512B-blocks      Used Available Use% Mounted on\n"
//usage:       "/dev/sda3             17381728  17107080    274648  98% /\n"
//usage:       "$ POSIXLY_CORRECT=yep df -P /dev/sda3\n"
//usage:       "Filesystem          512-blocks      Used Available Capacity Mounted on\n"
//usage:       "/dev/sda3             17381728  17107080    274648      98% /\n"

#include <mntent.h>
#include <sys/vfs.h>
#include "libbb.h"
#include "unicode.h"

#if !ENABLE_FEATURE_HUMAN_READABLE
static unsigned long kscale(unsigned long b, unsigned long bs)
{
    return (b * (unsigned long long) bs + 1024/2) / 1024;
}
#endif

int df_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int df_main(int argc UNUSED_PARAM, char **argv)
{
    unsigned long blocks_used;
    unsigned blocks_percent_used;
    unsigned long df_disp_hr = 1024;
    int status = EXIT_SUCCESS;
    unsigned opt;
    FILE *mount_table;
    struct mntent *mount_entry;
    struct statfs s;

    enum {
        OPT_KILO  = (1 << 0),
        OPT_POSIX = (1 << 1),
        OPT_ALL   = (1 << 2) * ENABLE_FEATURE_DF_FANCY,
        OPT_INODE = (1 << 3) * ENABLE_FEATURE_DF_FANCY,
        OPT_BSIZE = (1 << 4) * ENABLE_FEATURE_DF_FANCY,
        OPT_HUMAN = (1 << (2 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
        OPT_MEGA  = (1 << (3 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
    };
    const char *disp_units_hdr = NULL;
    char *chp;

    init_unicode();

#if ENABLE_FEATURE_HUMAN_READABLE && ENABLE_FEATURE_DF_FANCY
    opt_complementary = "k-mB:m-Bk:B-km";
#elif ENABLE_FEATURE_HUMAN_READABLE
    opt_complementary = "k-m:m-k";
#endif
    opt = getopt32(argv, "kP"
            IF_FEATURE_DF_FANCY("aiB:")
            IF_FEATURE_HUMAN_READABLE("hm")
            IF_FEATURE_DF_FANCY(, &chp));
    if (opt & OPT_MEGA)
        df_disp_hr = 1024*1024;

    if (opt & OPT_BSIZE)
        df_disp_hr = xatoul_range(chp, 1, ULONG_MAX); /* disallow 0 */

    /* From the manpage of df from coreutils-6.10:
     * Disk space is shown in 1K blocks by default, unless the environment
     * variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.
     */
    if (getenv("POSIXLY_CORRECT")) /* TODO - a new libbb function? */
        df_disp_hr = 512;

    if (opt & OPT_HUMAN) {
        df_disp_hr = 0;
        disp_units_hdr = "     Size";
    }
    if (opt & OPT_INODE)
        disp_units_hdr = "   Inodes";

    if (disp_units_hdr == NULL) {
#if ENABLE_FEATURE_HUMAN_READABLE
        disp_units_hdr = xasprintf("%s-blocks",
            /* print df_disp_hr, show no fractionals,
             * use suffixes if OPT_POSIX is set in opt */
            make_human_readable_str(df_disp_hr, 0, !!(opt & OPT_POSIX))
        );
#else
        disp_units_hdr = xasprintf("%lu-blocks", df_disp_hr);
#endif
    }
    printf("Filesystem           %-15sUsed Available %s Mounted on\n",
            disp_units_hdr, (opt & OPT_POSIX) ? "Capacity" : "Use%");

    mount_table = NULL;
    argv += optind;
    if (!argv[0]) {
        mount_table = setmntent(bb_path_mtab_file, "r");
        if (!mount_table)
            bb_perror_msg_and_die(bb_path_mtab_file);
    }

    while (1) {
        const char *device;
        const char *mount_point;

        if (mount_table) {
            mount_entry = getmntent(mount_table);
            if (!mount_entry) {
                endmntent(mount_table);
                break;
            }
        } else {
            mount_point = *argv++;
            if (!mount_point)
                break;
            mount_entry = find_mount_point(mount_point, 1);
            if (!mount_entry) {
                bb_error_msg("%s: can't find mount point", mount_point);
 set_error:
                status = EXIT_FAILURE;
                continue;
            }
        }

        device = mount_entry->mnt_fsname;
        mount_point = mount_entry->mnt_dir;

        if (statfs(mount_point, &s) != 0) {
            bb_simple_perror_msg(mount_point);
            goto set_error;
        }

        if ((s.f_blocks > 0) || !mount_table || (opt & OPT_ALL)) {
            if (opt & OPT_INODE) {
                s.f_blocks = s.f_files;
                s.f_bavail = s.f_bfree = s.f_ffree;
                s.f_bsize = 1;

                if (df_disp_hr)
                    df_disp_hr = 1;
            }
            blocks_used = s.f_blocks - s.f_bfree;
            blocks_percent_used = 0;
            if (blocks_used + s.f_bavail) {
                blocks_percent_used = (blocks_used * 100ULL
                        + (blocks_used + s.f_bavail)/2
                        ) / (blocks_used + s.f_bavail);
            }

            /* GNU coreutils 6.10 skips certain mounts, try to be compatible.  */
            if (ENABLE_FEATURE_SKIP_ROOTFS && strcmp(device, "rootfs") == 0)
                continue;

#ifdef WHY_WE_DO_IT_FOR_DEV_ROOT_ONLY
            if (strcmp(device, "/dev/root") == 0) {
                /* Adjusts device to be the real root device,
                 * or leaves device alone if it can't find it */
                device = find_block_device("/");
                if (!device) {
                    goto set_error;
                }
            }
#endif

#if ENABLE_UNICODE_SUPPORT
            {
                uni_stat_t uni_stat;
                char *uni_dev = unicode_conv_to_printable(&uni_stat, device);
                if (uni_stat.unicode_width > 20 && !(opt & OPT_POSIX)) {
                    printf("%s\n%20s", uni_dev, "");
                } else {
                    printf("%s%*s", uni_dev, 20 - (int)uni_stat.unicode_width, "");
                }
                free(uni_dev);
            }
#else
            if (printf("\n%-20s" + 1, device) > 20 && !(opt & OPT_POSIX))
                printf("\n%-20s", "");
#endif

#if ENABLE_FEATURE_HUMAN_READABLE
            printf(" %9s ",
                /* f_blocks x f_bsize / df_disp_hr, show one fractional,
                 * use suffixes if df_disp_hr == 0 */
                make_human_readable_str(s.f_blocks, s.f_bsize, df_disp_hr));

            printf(" %9s " + 1,
                /* EXPR x f_bsize / df_disp_hr, show one fractional,
                 * use suffixes if df_disp_hr == 0 */
                make_human_readable_str((s.f_blocks - s.f_bfree),
                        s.f_bsize, df_disp_hr));

            printf("%9s %3u%% %s\n",
                /* f_bavail x f_bsize / df_disp_hr, show one fractional,
                 * use suffixes if df_disp_hr == 0 */
                make_human_readable_str(s.f_bavail, s.f_bsize, df_disp_hr),
                blocks_percent_used, mount_point);
#else
            printf(" %9lu %9lu %9lu %3u%% %s\n",
                kscale(s.f_blocks, s.f_bsize),
                kscale(s.f_blocks - s.f_bfree, s.f_bsize),
                kscale(s.f_bavail, s.f_bsize),
                blocks_percent_used, mount_point);
#endif
        }
    }

    return status;
}