source: MondoRescue/branches/3.3/mindi-busybox/coreutils/du.c

/* vi: set sw=4 ts=4: */
/*
 * Mini du implementation for busybox
 *
 * Copyright (C) 1999,2000,2001 by Lineo, inc. and John Beppu
 * Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
 * Copyright (C) 2002  Edward Betts <edward@debian.org>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

/* BB_AUDIT SUSv3 compliant (unless default blocksize set to 1k) */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/du.html */

/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
 *
 * Mostly rewritten for SUSv3 compliance and to fix bugs/defects.
 * 1) Added support for SUSv3 -a, -H, -L, gnu -c, and (busybox) -d options.
 *    The -d option allows setting of max depth (similar to gnu --max-depth).
 * 2) Fixed incorrect size calculations for links and directories, especially
 *    when errors occurred.  Calculates sizes should now match gnu du output.
 * 3) Added error checking of output.
 * 4) Fixed busybox bug #1284 involving long overflow with human_readable.
 */

//usage:#define du_trivial_usage
//usage:       "[-aHLdclsx" IF_FEATURE_HUMAN_READABLE("hm") "k] [FILE]..."
//usage:#define du_full_usage "\n\n"
//usage:       "Summarize disk space used for each FILE and/or directory\n"
//usage:     "\n    -a  Show file sizes too"
//usage:     "\n    -L  Follow all symlinks"
//usage:     "\n    -H  Follow symlinks on command line"
//usage:     "\n    -d N    Limit output to directories (and files with -a) of depth < N"
//usage:     "\n    -c  Show grand total"
//usage:     "\n    -l  Count sizes many times if hard linked"
//usage:     "\n    -s  Display only a total for each argument"
//usage:     "\n    -x  Skip directories on different filesystems"
//usage:    IF_FEATURE_HUMAN_READABLE(
//usage:     "\n    -h  Sizes in human readable format (e.g., 1K 243M 2G)"
//usage:     "\n    -m  Sizes in megabytes"
//usage:    )
//usage:     "\n    -k  Sizes in kilobytes" IF_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(" (default)")
//usage:    IF_NOT_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(
//usage:     "\n        Default unit is 512 bytes"
//usage:    )
//usage:
//usage:#define du_example_usage
//usage:       "$ du\n"
//usage:       "16      ./CVS\n"
//usage:       "12      ./kernel-patches/CVS\n"
//usage:       "80      ./kernel-patches\n"
//usage:       "12      ./tests/CVS\n"
//usage:       "36      ./tests\n"
//usage:       "12      ./scripts/CVS\n"
//usage:       "16      ./scripts\n"
//usage:       "12      ./docs/CVS\n"
//usage:       "104     ./docs\n"
//usage:       "2417    .\n"

#include "libbb.h"
#include "common_bufsiz.h"

enum {
    OPT_a_files_too    = (1 << 0),
    OPT_H_follow_links = (1 << 1),
    OPT_k_kbytes       = (1 << 2),
    OPT_L_follow_links = (1 << 3),
    OPT_s_total_norecurse = (1 << 4),
    OPT_x_one_FS       = (1 << 5),
    OPT_d_maxdepth     = (1 << 6),
    OPT_l_hardlinks    = (1 << 7),
    OPT_c_total        = (1 << 8),
    OPT_h_for_humans   = (1 << 9),
    OPT_m_mbytes       = (1 << 10),
};

struct globals {
#if ENABLE_FEATURE_HUMAN_READABLE
    unsigned long disp_unit;
#else
    unsigned disp_k;
#endif
    int max_print_depth;
    bool status;
    int slink_depth;
    int du_depth;
    dev_t dir_dev;
} FIX_ALIASING;
#define G (*(struct globals*)bb_common_bufsiz1)
#define INIT_G() do { setup_common_bufsiz(); } while (0)


static void print(unsigned long long size, const char *filename)
{
    /* TODO - May not want to defer error checking here. */
#if ENABLE_FEATURE_HUMAN_READABLE
# if ENABLE_DESKTOP
    /* ~30 bytes of code for extra comtat:
     * coreutils' du rounds sizes up:
     * for example,  1025k file is shown as "2" by du -m.
     * We round to nearest if human-readable [too hard to fix],
     * else (fixed scale such as -m), we round up. To that end,
     * add yet another half of the unit before displaying:
     */
    if (G.disp_unit)
        size += (G.disp_unit-1) / (unsigned)(512 * 2);
# endif
    printf("%s\t%s\n",
            /* size x 512 / G.disp_unit.
             * If G.disp_unit == 0, show one fractional
             * and use suffixes
             */
            make_human_readable_str(size, 512, G.disp_unit),
            filename);
#else
    if (G.disp_k) {
        size++;
        size >>= 1;
    }
    printf("%llu\t%s\n", size, filename);
#endif
}

/* tiny recursive du */
static unsigned long long du(const char *filename)
{
    struct stat statbuf;
    unsigned long long sum;

    if (lstat(filename, &statbuf) != 0) {
        bb_simple_perror_msg(filename);
        G.status = EXIT_FAILURE;
        return 0;
    }

    if (option_mask32 & OPT_x_one_FS) {
        if (G.du_depth == 0) {
            G.dir_dev = statbuf.st_dev;
        } else if (G.dir_dev != statbuf.st_dev) {
            return 0;
        }
    }

    sum = statbuf.st_blocks;

    if (S_ISLNK(statbuf.st_mode)) {
        if (G.slink_depth > G.du_depth) { /* -H or -L */
            if (stat(filename, &statbuf) != 0) {
                bb_simple_perror_msg(filename);
                G.status = EXIT_FAILURE;
                return 0;
            }
            sum = statbuf.st_blocks;
            if (G.slink_depth == 1) {
                /* Convert -H to -L */
                G.slink_depth = INT_MAX;
            }
        }
    }

    if (!(option_mask32 & OPT_l_hardlinks)
     && statbuf.st_nlink > 1
    ) {
        /* Add files/directories with links only once */
        if (is_in_ino_dev_hashtable(&statbuf)) {
            return 0;
        }
        add_to_ino_dev_hashtable(&statbuf, NULL);
    }

    if (S_ISDIR(statbuf.st_mode)) {
        DIR *dir;
        struct dirent *entry;
        char *newfile;

        dir = warn_opendir(filename);
        if (!dir) {
            G.status = EXIT_FAILURE;
            return sum;
        }

        while ((entry = readdir(dir))) {
            newfile = concat_subpath_file(filename, entry->d_name);
            if (newfile == NULL)
                continue;
            ++G.du_depth;
            sum += du(newfile);
            --G.du_depth;
            free(newfile);
        }
        closedir(dir);
    } else {
        if (!(option_mask32 & OPT_a_files_too) && G.du_depth != 0)
            return sum;
    }
    if (G.du_depth <= G.max_print_depth) {
        print(sum, filename);
    }
    return sum;
}

int du_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int du_main(int argc UNUSED_PARAM, char **argv)
{
    unsigned long long total;
    int slink_depth_save;
    unsigned opt;

    INIT_G();

#if ENABLE_FEATURE_HUMAN_READABLE
    IF_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(G.disp_unit = 1024;)
    IF_NOT_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(G.disp_unit = 512;)
    if (getenv("POSIXLY_CORRECT"))  /* TODO - a new libbb function? */
        G.disp_unit = 512;
#else
    IF_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(G.disp_k = 1;)
    /* IF_NOT_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(G.disp_k = 0;) - G is pre-zeroed */
#endif
    G.max_print_depth = INT_MAX;

    /* Note: SUSv3 specifies that -a and -s options cannot be used together
     * in strictly conforming applications.  However, it also says that some
     * du implementations may produce output when -a and -s are used together.
     * gnu du exits with an error code in this case.  We choose to simply
     * ignore -a.  This is consistent with -s being equivalent to -d 0.
     */
#if ENABLE_FEATURE_HUMAN_READABLE
    opt_complementary = "h-km:k-hm:m-hk:H-L:L-H:s-d:d-s:d+";
    opt = getopt32(argv, "aHkLsx" "d:" "lc" "hm", &G.max_print_depth);
    argv += optind;
    if (opt & OPT_h_for_humans) {
        G.disp_unit = 0;
    }
    if (opt & OPT_m_mbytes) {
        G.disp_unit = 1024*1024;
    }
    if (opt & OPT_k_kbytes) {
        G.disp_unit = 1024;
    }
#else
    opt_complementary = "H-L:L-H:s-d:d-s:d+";
    opt = getopt32(argv, "aHkLsx" "d:" "lc", &G.max_print_depth);
    argv += optind;
#if !ENABLE_FEATURE_DU_DEFAULT_BLOCKSIZE_1K
    if (opt & OPT_k_kbytes) {
        G.disp_k = 1;
    }
#endif
#endif
    if (opt & OPT_H_follow_links) {
        G.slink_depth = 1;
    }
    if (opt & OPT_L_follow_links) {
        G.slink_depth = INT_MAX;
    }
    if (opt & OPT_s_total_norecurse) {
        G.max_print_depth = 0;
    }

    /* go through remaining args (if any) */
    if (!*argv) {
        *--argv = (char*)".";
        if (G.slink_depth == 1) {
            G.slink_depth = 0;
        }
    }

    slink_depth_save = G.slink_depth;
    total = 0;
    do {
        total += du(*argv);
        /* otherwise du /dir /dir won't show /dir twice: */
        reset_ino_dev_hashtable();
        G.slink_depth = slink_depth_save;
    } while (*++argv);

    if (opt & OPT_c_total)
        print(total, "total");

    fflush_stdout_and_exit(G.status);
}