LXR busybox/coreutils/df.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * Mini df implementation for busybox
   4 *
   5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   6 * based on original code by (I think) Bruce Perens <bruce@pixar.com>.
   7 *
   8 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   9 */
  10/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
  11 *
  12 * Size reduction.  Removed floating point dependency.  Added error checking
  13 * on output.  Output stats on 0-sized filesystems if specifically listed on
  14 * the command line.  Properly round *-blocks, Used, and Available quantities.
  15 *
  16 * Aug 28, 2008      Bernhard Reutner-Fischer
  17 *
  18 * Implement -P and -B; better coreutils compat; cleanup
  19 */
  20//config:config DF
  21//config:       bool "df (6.8 kb)"
  22//config:       default y
  23//config:       help
  24//config:       df reports the amount of disk space used and available
  25//config:       on filesystems.
  26//config:
  27//config:config FEATURE_DF_FANCY
  28//config:       bool "Enable -a, -i, -B"
  29//config:       default y
  30//config:       depends on DF
  31//config:       help
  32//config:       -a Show all filesystems
  33//config:       -i Inodes
  34//config:       -B <SIZE> Blocksize
  35
  36//applet:IF_DF(APPLET_NOEXEC(df, df, BB_DIR_BIN, BB_SUID_DROP, df))
  37
  38//kbuild:lib-$(CONFIG_DF) += df.o
  39
  40/* BB_AUDIT SUSv3 _NOT_ compliant -- option -t missing. */
  41/* http://www.opengroup.org/onlinepubs/007904975/utilities/df.html */
  42
  43//usage:#define df_trivial_usage
  44//usage:        "[-Pk"
  45//usage:        IF_FEATURE_HUMAN_READABLE("mh")
  46//usage:        "T"
  47//usage:        IF_FEATURE_DF_FANCY("ai] [-B SIZE")
  48//usage:        "] [-t TYPE] [FILESYSTEM]..."
  49//usage:#define df_full_usage "\n\n"
  50//usage:       "Print filesystem usage statistics\n"
  51//usage:     "\n        -P      POSIX output format"
  52//usage:     "\n        -k      1024-byte blocks (default)"
  53//usage:        IF_FEATURE_HUMAN_READABLE(
  54//usage:     "\n        -m      1M-byte blocks"
  55//usage:     "\n        -h      Human readable (e.g. 1K 243M 2G)"
  56//usage:        )
  57//usage:     "\n        -T      Print filesystem type"
  58//usage:     "\n        -t TYPE Print only mounts of this type"
  59//usage:        IF_FEATURE_DF_FANCY(
  60//usage:     "\n        -a      Show all filesystems"
  61//usage:     "\n        -i      Inodes"
  62//usage:     "\n        -B SIZE Blocksize"
  63//usage:        )
  64//usage:
  65//usage:#define df_example_usage
  66//usage:       "$ df\n"
  67//usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
  68//usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
  69//usage:       "/dev/sda1                64216     36364     27852  57% /boot\n"
  70//usage:       "$ df /dev/sda3\n"
  71//usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
  72//usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
  73//usage:       "$ POSIXLY_CORRECT=sure df /dev/sda3\n"
  74//usage:       "Filesystem         512B-blocks      Used Available Use% Mounted on\n"
  75//usage:       "/dev/sda3             17381728  17107080    274648  98% /\n"
  76//usage:       "$ POSIXLY_CORRECT=yep df -P /dev/sda3\n"
  77//usage:       "Filesystem          512-blocks      Used Available Capacity Mounted on\n"
  78//usage:       "/dev/sda3             17381728  17107080    274648      98% /\n"
  79
  80#include <mntent.h>
  81#include <sys/statvfs.h>
  82#include "libbb.h"
  83#include "unicode.h"
  84
  85#if !ENABLE_FEATURE_HUMAN_READABLE
  86static unsigned long kscale(unsigned long b, unsigned long bs)
  87{
  88        return (b * (unsigned long long) bs + 1024/2) / 1024;
  89}
  90#endif
  91
  92int df_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  93int df_main(int argc UNUSED_PARAM, char **argv)
  94{
  95        unsigned long df_disp_hr = 1024;
  96        int status = EXIT_SUCCESS;
  97        unsigned opt;
  98        FILE *mount_table;
  99        struct mntent *mount_entry;
 100        struct statvfs s;
 101        enum {
 102                OPT_KILO   = (1 << 0),
 103                OPT_POSIX  = (1 << 1),
 104                OPT_FSTYPE = (1 << 2),
 105                OPT_t      = (1 << 3),
 106                OPT_ALL    = (1 << 4) * ENABLE_FEATURE_DF_FANCY,
 107                OPT_INODE  = (1 << 5) * ENABLE_FEATURE_DF_FANCY,
 108                OPT_BSIZE  = (1 << 6) * ENABLE_FEATURE_DF_FANCY,
 109                OPT_HUMAN  = (1 << (4 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
 110                OPT_MEGA   = (1 << (5 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
 111        };
 112        const char *disp_units_hdr = NULL;
 113        char *chp, *opt_t;
 114
 115        init_unicode();
 116
 117        /* From the manpage of df from coreutils-6.10:
 118         * Disk space is shown in 1K blocks by default, unless the environment
 119         * variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.
 120         */
 121        if (getenv("POSIXLY_CORRECT")) /* TODO - a new libbb function? */
 122                df_disp_hr = 512;
 123
 124        opt = getopt32(argv, "^"
 125                        "kPTt:"
 126                        IF_FEATURE_DF_FANCY("aiB:")
 127                        IF_FEATURE_HUMAN_READABLE("hm")
 128                        "\0"
 129#if ENABLE_FEATURE_HUMAN_READABLE && ENABLE_FEATURE_DF_FANCY
 130                        "k-mB:m-Bk:B-km"
 131#elif ENABLE_FEATURE_HUMAN_READABLE
 132                        "k-m:m-k"
 133#endif
 134                        , &opt_t
 135                        IF_FEATURE_DF_FANCY(, &chp)
 136        );
 137        if (opt & OPT_MEGA)
 138                df_disp_hr = 1024*1024;
 139
 140        if (opt & OPT_BSIZE) {
 141                /* GNU coreutils 8.25 accepts "-BMiB" form too */
 142                int i;
 143                for (i = 0; kmg_i_suffixes[i].suffix[0]; i++) {
 144                        if (strcmp(kmg_i_suffixes[i].suffix, chp) == 0) {
 145                                df_disp_hr = kmg_i_suffixes[i].mult;
 146                                goto got_it;
 147                        }
 148                }
 149                /* Range used to disallow 0 */
 150                df_disp_hr = xatoul_range_sfx(chp, 1, ULONG_MAX, kmg_i_suffixes);
 151 got_it: ;
 152        }
 153
 154        if (opt & OPT_HUMAN) {
 155                df_disp_hr = 0;
 156                disp_units_hdr = "     Size";
 157        }
 158        if (opt & OPT_INODE)
 159                disp_units_hdr = "   Inodes";
 160
 161        if (disp_units_hdr == NULL) {
 162#if ENABLE_FEATURE_HUMAN_READABLE
 163                disp_units_hdr = xasprintf("%s-blocks",
 164                        /* print df_disp_hr, show no fractionals,
 165                         * use suffixes if OPT_POSIX is set in opt */
 166                        make_human_readable_str(df_disp_hr, 0, !!(opt & OPT_POSIX))
 167                );
 168#else
 169                disp_units_hdr = xasprintf("%lu-blocks", df_disp_hr);
 170#endif
 171        }
 172
 173        printf("Filesystem           %s%-15sUsed Available %s Mounted on\n",
 174                        (opt & OPT_FSTYPE) ? "Type       " : "",
 175                        disp_units_hdr,
 176                        (opt & OPT_POSIX) ? "Capacity" : "Use%");
 177
 178        mount_table = NULL;
 179        argv += optind;
 180        if (!argv[0]) {
 181                mount_table = setmntent(bb_path_mtab_file, "r");
 182                if (!mount_table)
 183                        bb_simple_perror_msg_and_die(bb_path_mtab_file);
 184        }
 185
 186        while (1) {
 187                const char *device;
 188                const char *mount_point;
 189                const char *fs_type;
 190
 191                if (mount_table) {
 192                        mount_entry = getmntent(mount_table);
 193                        if (!mount_entry) {
 194                                endmntent(mount_table);
 195                                break;
 196                        }
 197                } else {
 198                        mount_point = *argv++;
 199                        if (!mount_point)
 200                                break;
 201                        mount_entry = find_mount_point(mount_point, 1);
 202                        if (!mount_entry) {
 203                                bb_error_msg("%s: can't find mount point", mount_point);
 204 set_error:
 205                                status = EXIT_FAILURE;
 206                                continue;
 207                        }
 208                }
 209
 210                device = mount_entry->mnt_fsname;
 211
 212                /* GNU coreutils 6.10 skips certain mounts, try to be compatible */
 213                if (ENABLE_FEATURE_SKIP_ROOTFS && strcmp(device, "rootfs") == 0)
 214                        continue;
 215
 216                mount_point = mount_entry->mnt_dir;
 217                fs_type = mount_entry->mnt_type;
 218
 219                if (opt & OPT_t) {
 220                        if (strcmp(fs_type, opt_t) != 0)
 221                                continue;
 222                }
 223
 224                if (statvfs(mount_point, &s) != 0) {
 225                        bb_simple_perror_msg(mount_point);
 226                        goto set_error;
 227                }
 228                /* Some uclibc versions were seen to lose f_frsize
 229                 * (kernel does return it, but then uclibc does not copy it)
 230                 */
 231                if (s.f_frsize == 0)
 232                        s.f_frsize = s.f_bsize;
 233
 234                if ((s.f_blocks > 0) || !mount_table || (opt & OPT_ALL)) {
 235                        unsigned long long blocks_used;
 236                        unsigned long long blocks_total;
 237                        unsigned blocks_percent_used;
 238
 239                        if (opt & OPT_INODE) {
 240                                s.f_blocks = s.f_files;
 241                                s.f_bavail = s.f_bfree = s.f_ffree;
 242                                s.f_frsize = 1;
 243                                if (df_disp_hr)
 244                                        df_disp_hr = 1;
 245                        }
 246                        blocks_used = s.f_blocks - s.f_bfree;
 247                        blocks_total = blocks_used + s.f_bavail;
 248                        blocks_percent_used = blocks_total; /* 0% if blocks_total == 0, else... */
 249                        if (blocks_total != 0) {
 250                                /* Downscale sizes for narrower division */
 251                                unsigned u;
 252                                while (blocks_total >= INT_MAX / 101) {
 253                                        blocks_total >>= 1;
 254                                        blocks_used >>= 1;
 255                                }
 256                                u = (unsigned)blocks_used * 100u + (unsigned)blocks_total / 2;
 257                                blocks_percent_used = u / (unsigned)blocks_total;
 258                        }
 259
 260#ifdef WHY_WE_DO_IT_FOR_DEV_ROOT_ONLY
 261                        if (strcmp(device, "/dev/root") == 0) {
 262                                /* Adjusts device to be the real root device,
 263                                 * or leaves device alone if it can't find it */
 264                                device = find_block_device("/");
 265                                if (!device) {
 266                                        goto set_error;
 267                                }
 268                        }
 269#endif
 270
 271#if ENABLE_UNICODE_SUPPORT
 272                        {
 273                                uni_stat_t uni_stat;
 274                                char *uni_dev = unicode_conv_to_printable(&uni_stat, device);
 275                                if (uni_stat.unicode_width > 20 && !(opt & OPT_POSIX)) {
 276                                        printf("%s\n%20s", uni_dev, "");
 277                                } else {
 278                                        printf("%s%*s", uni_dev, 20 - (int)uni_stat.unicode_width, "");
 279                                }
 280                                free(uni_dev);
 281                                if (opt & OPT_FSTYPE) {
 282                                        char *uni_type = unicode_conv_to_printable(&uni_stat, fs_type);
 283                                        if (uni_stat.unicode_width > 10 && !(opt & OPT_POSIX))
 284                                                printf(" %s\n%31s", uni_type, "");
 285                                        else
 286                                                printf(" %s%*s", uni_type, 10 - (int)uni_stat.unicode_width, "");
 287                                        free(uni_type);
 288                                }
 289                        }
 290#else
 291                        if (printf("\n%-20s" + 1, device) > 20 && !(opt & OPT_POSIX))
 292                                printf("\n%-20s", "");
 293                        if (opt & OPT_FSTYPE) {
 294                                if (printf(" %-10s", fs_type) > 11 && !(opt & OPT_POSIX))
 295                                        printf("\n%-30s", "");
 296                        }
 297#endif
 298
 299#if ENABLE_FEATURE_HUMAN_READABLE
 300                        printf(" %9s ",
 301                                /* f_blocks x f_frsize / df_disp_hr, show one fractional,
 302                                 * use suffixes if df_disp_hr == 0 */
 303                                make_human_readable_str(s.f_blocks, s.f_frsize, df_disp_hr));
 304
 305                        printf(" %9s " + 1,
 306                                /* EXPR x f_frsize / df_disp_hr, show one fractional,
 307                                 * use suffixes if df_disp_hr == 0 */
 308                                make_human_readable_str((s.f_blocks - s.f_bfree),
 309                                                s.f_frsize, df_disp_hr));
 310
 311                        printf("%9s %3u%% %s\n",
 312                                /* f_bavail x f_frsize / df_disp_hr, show one fractional,
 313                                 * use suffixes if df_disp_hr == 0 */
 314                                make_human_readable_str(s.f_bavail, s.f_frsize, df_disp_hr),
 315                                blocks_percent_used, mount_point);
 316#else
 317                        printf(" %9lu %9lu %9lu %3u%% %s\n",
 318                                kscale(s.f_blocks, s.f_frsize),
 319                                kscale(s.f_blocks - s.f_bfree, s.f_frsize),
 320                                kscale(s.f_bavail, s.f_frsize),
 321                                blocks_percent_used, mount_point);
 322#endif
 323                }
 324        }
 325
 326        return status;
 327}
 328