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
  11/* BB_AUDIT SUSv3 _NOT_ compliant -- option -t missing. */
  12/* http://www.opengroup.org/onlinepubs/007904975/utilities/df.html */
  13
  14/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
  15 *
  16 * Size reduction.  Removed floating point dependency.  Added error checking
  17 * on output.  Output stats on 0-sized filesystems if specifically listed on
  18 * the command line.  Properly round *-blocks, Used, and Available quantities.
  19 *
  20 * Aug 28, 2008      Bernhard Reutner-Fischer
  21 *
  22 * Implement -P and -B; better coreutils compat; cleanup
  23 */
  24
  25//usage:#define df_trivial_usage
  26//usage:        "[-Pk"
  27//usage:        IF_FEATURE_HUMAN_READABLE("mh")
  28//usage:        IF_FEATURE_DF_FANCY("ai] [-B SIZE")
  29//usage:        "] [FILESYSTEM]..."
  30//usage:#define df_full_usage "\n\n"
  31//usage:       "Print filesystem usage statistics\n"
  32//usage:     "\n        -P      POSIX output format"
  33//usage:     "\n        -k      1024-byte blocks (default)"
  34//usage:        IF_FEATURE_HUMAN_READABLE(
  35//usage:     "\n        -m      1M-byte blocks"
  36//usage:     "\n        -h      Human readable (e.g. 1K 243M 2G)"
  37//usage:        )
  38//usage:        IF_FEATURE_DF_FANCY(
  39//usage:     "\n        -a      Show all filesystems"
  40//usage:     "\n        -i      Inodes"
  41//usage:     "\n        -B SIZE Blocksize"
  42//usage:        )
  43//usage:
  44//usage:#define df_example_usage
  45//usage:       "$ df\n"
  46//usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
  47//usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
  48//usage:       "/dev/sda1                64216     36364     27852  57% /boot\n"
  49//usage:       "$ df /dev/sda3\n"
  50//usage:       "Filesystem           1K-blocks      Used Available Use% Mounted on\n"
  51//usage:       "/dev/sda3              8690864   8553540    137324  98% /\n"
  52//usage:       "$ POSIXLY_CORRECT=sure df /dev/sda3\n"
  53//usage:       "Filesystem         512B-blocks      Used Available Use% Mounted on\n"
  54//usage:       "/dev/sda3             17381728  17107080    274648  98% /\n"
  55//usage:       "$ POSIXLY_CORRECT=yep df -P /dev/sda3\n"
  56//usage:       "Filesystem          512-blocks      Used Available Capacity Mounted on\n"
  57//usage:       "/dev/sda3             17381728  17107080    274648      98% /\n"
  58
  59#include <mntent.h>
  60#include <sys/vfs.h>
  61#include "libbb.h"
  62#include "unicode.h"
  63
  64#if !ENABLE_FEATURE_HUMAN_READABLE
  65static unsigned long kscale(unsigned long b, unsigned long bs)
  66{
  67        return (b * (unsigned long long) bs + 1024/2) / 1024;
  68}
  69#endif
  70
  71int df_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  72int df_main(int argc UNUSED_PARAM, char **argv)
  73{
  74        unsigned long blocks_used;
  75        unsigned blocks_percent_used;
  76        unsigned long df_disp_hr = 1024;
  77        int status = EXIT_SUCCESS;
  78        unsigned opt;
  79        FILE *mount_table;
  80        struct mntent *mount_entry;
  81        struct statfs s;
  82
  83        enum {
  84                OPT_KILO  = (1 << 0),
  85                OPT_POSIX = (1 << 1),
  86                OPT_ALL   = (1 << 2) * ENABLE_FEATURE_DF_FANCY,
  87                OPT_INODE = (1 << 3) * ENABLE_FEATURE_DF_FANCY,
  88                OPT_BSIZE = (1 << 4) * ENABLE_FEATURE_DF_FANCY,
  89                OPT_HUMAN = (1 << (2 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
  90                OPT_MEGA  = (1 << (3 + 3*ENABLE_FEATURE_DF_FANCY)) * ENABLE_FEATURE_HUMAN_READABLE,
  91        };
  92        const char *disp_units_hdr = NULL;
  93        char *chp;
  94
  95        init_unicode();
  96
  97#if ENABLE_FEATURE_HUMAN_READABLE && ENABLE_FEATURE_DF_FANCY
  98        opt_complementary = "k-mB:m-Bk:B-km";
  99#elif ENABLE_FEATURE_HUMAN_READABLE
 100        opt_complementary = "k-m:m-k";
 101#endif
 102        opt = getopt32(argv, "kP"
 103                        IF_FEATURE_DF_FANCY("aiB:")
 104                        IF_FEATURE_HUMAN_READABLE("hm")
 105                        IF_FEATURE_DF_FANCY(, &chp));
 106        if (opt & OPT_MEGA)
 107                df_disp_hr = 1024*1024;
 108
 109        if (opt & OPT_BSIZE)
 110                df_disp_hr = xatoul_range(chp, 1, ULONG_MAX); /* disallow 0 */
 111
 112        /* From the manpage of df from coreutils-6.10:
 113         * Disk space is shown in 1K blocks by default, unless the environment
 114         * variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.
 115         */
 116        if (getenv("POSIXLY_CORRECT")) /* TODO - a new libbb function? */
 117                df_disp_hr = 512;
 118
 119        if (opt & OPT_HUMAN) {
 120                df_disp_hr = 0;
 121                disp_units_hdr = "     Size";
 122        }
 123        if (opt & OPT_INODE)
 124                disp_units_hdr = "   Inodes";
 125
 126        if (disp_units_hdr == NULL) {
 127#if ENABLE_FEATURE_HUMAN_READABLE
 128                disp_units_hdr = xasprintf("%s-blocks",
 129                        /* print df_disp_hr, show no fractionals,
 130                         * use suffixes if OPT_POSIX is set in opt */
 131                        make_human_readable_str(df_disp_hr, 0, !!(opt & OPT_POSIX))
 132                );
 133#else
 134                disp_units_hdr = xasprintf("%lu-blocks", df_disp_hr);
 135#endif
 136        }
 137        printf("Filesystem           %-15sUsed Available %s Mounted on\n",
 138                        disp_units_hdr, (opt & OPT_POSIX) ? "Capacity" : "Use%");
 139
 140        mount_table = NULL;
 141        argv += optind;
 142        if (!argv[0]) {
 143                mount_table = setmntent(bb_path_mtab_file, "r");
 144                if (!mount_table)
 145                        bb_perror_msg_and_die(bb_path_mtab_file);
 146        }
 147
 148        while (1) {
 149                const char *device;
 150                const char *mount_point;
 151
 152                if (mount_table) {
 153                        mount_entry = getmntent(mount_table);
 154                        if (!mount_entry) {
 155                                endmntent(mount_table);
 156                                break;
 157                        }
 158                } else {
 159                        mount_point = *argv++;
 160                        if (!mount_point)
 161                                break;
 162                        mount_entry = find_mount_point(mount_point, 1);
 163                        if (!mount_entry) {
 164                                bb_error_msg("%s: can't find mount point", mount_point);
 165 set_error:
 166                                status = EXIT_FAILURE;
 167                                continue;
 168                        }
 169                }
 170
 171                device = mount_entry->mnt_fsname;
 172                mount_point = mount_entry->mnt_dir;
 173
 174                if (statfs(mount_point, &s) != 0) {
 175                        bb_simple_perror_msg(mount_point);
 176                        goto set_error;
 177                }
 178
 179                if ((s.f_blocks > 0) || !mount_table || (opt & OPT_ALL)) {
 180                        if (opt & OPT_INODE) {
 181                                s.f_blocks = s.f_files;
 182                                s.f_bavail = s.f_bfree = s.f_ffree;
 183                                s.f_bsize = 1;
 184
 185                                if (df_disp_hr)
 186                                        df_disp_hr = 1;
 187                        }
 188                        blocks_used = s.f_blocks - s.f_bfree;
 189                        blocks_percent_used = 0;
 190                        if (blocks_used + s.f_bavail) {
 191                                blocks_percent_used = (blocks_used * 100ULL
 192                                                + (blocks_used + s.f_bavail)/2
 193                                                ) / (blocks_used + s.f_bavail);
 194                        }
 195
 196                        /* GNU coreutils 6.10 skips certain mounts, try to be compatible.  */
 197                        if (ENABLE_FEATURE_SKIP_ROOTFS && strcmp(device, "rootfs") == 0)
 198                                continue;
 199
 200#ifdef WHY_WE_DO_IT_FOR_DEV_ROOT_ONLY
 201                        if (strcmp(device, "/dev/root") == 0) {
 202                                /* Adjusts device to be the real root device,
 203                                 * or leaves device alone if it can't find it */
 204                                device = find_block_device("/");
 205                                if (!device) {
 206                                        goto set_error;
 207                                }
 208                        }
 209#endif
 210
 211#if ENABLE_UNICODE_SUPPORT
 212                        {
 213                                uni_stat_t uni_stat;
 214                                char *uni_dev = unicode_conv_to_printable(&uni_stat, device);
 215                                if (uni_stat.unicode_width > 20 && !(opt & OPT_POSIX)) {
 216                                        printf("%s\n%20s", uni_dev, "");
 217                                } else {
 218                                        printf("%s%*s", uni_dev, 20 - (int)uni_stat.unicode_width, "");
 219                                }
 220                                free(uni_dev);
 221                        }
 222#else
 223                        if (printf("\n%-20s" + 1, device) > 20 && !(opt & OPT_POSIX))
 224                                printf("\n%-20s", "");
 225#endif
 226
 227#if ENABLE_FEATURE_HUMAN_READABLE
 228                        printf(" %9s ",
 229                                /* f_blocks x f_bsize / df_disp_hr, show one fractional,
 230                                 * use suffixes if df_disp_hr == 0 */
 231                                make_human_readable_str(s.f_blocks, s.f_bsize, df_disp_hr));
 232
 233                        printf(" %9s " + 1,
 234                                /* EXPR x f_bsize / df_disp_hr, show one fractional,
 235                                 * use suffixes if df_disp_hr == 0 */
 236                                make_human_readable_str((s.f_blocks - s.f_bfree),
 237                                                s.f_bsize, df_disp_hr));
 238
 239                        printf("%9s %3u%% %s\n",
 240                                /* f_bavail x f_bsize / df_disp_hr, show one fractional,
 241                                 * use suffixes if df_disp_hr == 0 */
 242                                make_human_readable_str(s.f_bavail, s.f_bsize, df_disp_hr),
 243                                blocks_percent_used, mount_point);
 244#else
 245                        printf(" %9lu %9lu %9lu %3u%% %s\n",
 246                                kscale(s.f_blocks, s.f_bsize),
 247                                kscale(s.f_blocks - s.f_bfree, s.f_bsize),
 248                                kscale(s.f_bavail, s.f_bsize),
 249                                blocks_percent_used, mount_point);
 250#endif
 251                }
 252        }
 253
 254        return status;
 255}
 256