source: MondoRescue/branches/2.2.5/mindi-busybox/coreutils/df.c@ 1765

/* 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 tarball for details.
 */

/* BB_AUDIT SUSv3 _NOT_ compliant -- options -P and -t missing.  Also blocksize. */
/* 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.
 */

#include <mntent.h>
#include <sys/vfs.h>
#include "libbb.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);
int df_main(int argc, char **argv)
{
    unsigned long blocks_used;
    unsigned blocks_percent_used;
#if ENABLE_FEATURE_HUMAN_READABLE
    unsigned df_disp_hr = 1024;
#endif
    int status = EXIT_SUCCESS;
    unsigned opt;
    FILE *mount_table;
    struct mntent *mount_entry;
    struct statfs s;
    /* default display is kilobytes */
    const char *disp_units_hdr = "1k-blocks";

#if ENABLE_FEATURE_HUMAN_READABLE
    opt_complementary = "h-km:k-hm:m-hk";
    opt = getopt32(argv, "hmk");
    if (opt & 1) {
        df_disp_hr = 0;
        disp_units_hdr = "     Size";
    }
    if (opt & 2) {
        df_disp_hr = 1024*1024;
        disp_units_hdr = "1M-blocks";
    }
#else
    opt = getopt32(argv, "k");
#endif

    printf("Filesystem%11s%-15sUsed Available Use%% Mounted on\n",
              "", disp_units_hdr);

    mount_table = NULL;
    argv += optind;
    if (optind >= argc) {
        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, bb_path_mtab_file);
            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_perror_msg("%s", mount_point);
            goto SET_ERROR;
        }

        if ((s.f_blocks > 0) || !mount_table){
            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);
            }

            if (strcmp(device, "rootfs") == 0) {
                continue;
            } else 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;
                }
            }

            if (printf("\n%-20s" + 1, device) > 20)
                    printf("\n%-20s", "");
#if ENABLE_FEATURE_HUMAN_READABLE
            printf(" %9s ",
                make_human_readable_str(s.f_blocks, s.f_bsize, df_disp_hr));

            printf(" %9s " + 1,
                make_human_readable_str((s.f_blocks - s.f_bfree),
                        s.f_bsize, df_disp_hr));

            printf("%9s %3u%% %s\n",
                    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
        }
    }

    fflush_stdout_and_exit(status);
}