usr.bin/du/du.c

   1 /*      $NetBSD: du.c,v 1.36 2012/03/11 11:23:20 shattered Exp $        */
   2
   3 /*
   4  * Copyright (c) 1989, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Chris Newcomb.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 #ifndef lint
  37 __COPYRIGHT("@(#) Copyright (c) 1989, 1993, 1994\
  38  The Regents of the University of California.  All rights reserved.");
  39 #endif /* not lint */
  40
  41 #ifndef lint
  42 #if 0
  43 static char sccsid[] = "@(#)du.c        8.5 (Berkeley) 5/4/95";
  44 #else
  45 __RCSID("$NetBSD: du.c,v 1.36 2012/03/11 11:23:20 shattered Exp $");
  46 #endif
  47 #endif /* not lint */
  48
  49 #include <sys/param.h>
  50 #include <sys/types.h>
  51 #include <sys/stat.h>
  52
  53 #include <dirent.h>
  54 #include <err.h>
  55 #include <errno.h>
  56 #include <fts.h>
  57 #include <inttypes.h>
  58 #include <util.h>
  59 #include <stdio.h>
  60 #include <stdlib.h>
  61 #include <string.h>
  62 #include <unistd.h>
  63 #include <limits.h>
  64
  65 /* Count inodes or file size */
  66 #define COUNT   (iflag ? 1 : p->fts_statp->st_blocks)
  67
  68 static int      linkchk(dev_t, ino_t);
  69 static void     prstat(const char *, int64_t);
  70 __dead static void      usage(void);
  71
  72 static int hflag, iflag;
  73 static long blocksize;
  74
  75 int
  76 main(int argc, char *argv[])
  77 {
  78         FTS *fts;
  79         FTSENT *p;
  80         int64_t totalblocks;
  81         int ftsoptions, listfiles;
  82         int depth;
  83         int Hflag, Lflag, aflag, ch, cflag, dflag, gkmflag, nflag, rval, sflag;
  84         const char *noargv[2];
  85
  86         Hflag = Lflag = aflag = cflag = dflag = gkmflag = nflag = sflag = 0;
  87         totalblocks = 0;
  88         ftsoptions = FTS_PHYSICAL;
  89         depth = INT_MAX;
  90         while ((ch = getopt(argc, argv, "HLPacd:ghikmnrsx")) != -1)
  91                 switch (ch) {
  92                 case 'H':
  93                         Hflag = 1;
  94                         Lflag = 0;
  95                         break;
  96                 case 'L':
  97                         Lflag = 1;
  98                         Hflag = 0;
  99                         break;
 100                 case 'P':
 101                         Hflag = Lflag = 0;
 102                         break;
 103                 case 'a':
 104                         aflag = 1;
 105                         break;
 106                 case 'c':
 107                         cflag = 1;
 108                         break;
 109                 case 'd':
 110                         dflag = 1;
 111                         depth = atoi(optarg);
 112                         if (depth < 0 || depth > SHRT_MAX) {
 113                                 warnx("invalid argument to option d: %s",
 114                                         optarg);
 115                                 usage();
 116                         }
 117                         break;
 118                 case 'g':
 119                         blocksize = 1024 * 1024 * 1024;
 120                         gkmflag = 1;
 121                         break;
 122                 case 'h':
 123                         hflag = 1;
 124                         break;
 125                 case 'i':
 126                         iflag = 1;
 127                         break;
 128                 case 'k':
 129                         blocksize = 1024;
 130                         gkmflag = 1;
 131                         break;
 132                 case 'm':
 133                         blocksize = 1024 * 1024;
 134                         gkmflag = 1;
 135                         break;
 136                 case 'n':
 137                         nflag = 1;
 138                         break;
 139                 case 'r':
 140                         break;
 141                 case 's':
 142                         sflag = 1;
 143                         break;
 144                 case 'x':
 145                         ftsoptions |= FTS_XDEV;
 146                         break;
 147                 case '?':
 148                 default:
 149                         usage();
 150                 }
 151         argc -= optind;
 152         argv += optind;
 153
 154         /*
 155          * XXX
 156          * Because of the way that fts(3) works, logical walks will not count
 157          * the blocks actually used by symbolic links.  We rationalize this by
 158          * noting that users computing logical sizes are likely to do logical
 159          * copies, so not counting the links is correct.  The real reason is
 160          * that we'd have to re-implement the kernel's symbolic link traversing
 161          * algorithm to get this right.  If, for example, you have relative
 162          * symbolic links referencing other relative symbolic links, it gets
 163          * very nasty, very fast.  The bottom line is that it's documented in
 164          * the man page, so it's a feature.
 165          */
 166         if (Hflag)
 167                 ftsoptions |= FTS_COMFOLLOW;
 168         if (Lflag) {
 169                 ftsoptions &= ~FTS_PHYSICAL;
 170                 ftsoptions |= FTS_LOGICAL;
 171         }
 172
 173         listfiles = 0;
 174         if (aflag) {
 175                 if (sflag || dflag)
 176                         usage();
 177                 listfiles = 1;
 178         } else if (sflag) {
 179                 if (dflag)
 180                         usage();
 181                 depth = 0;
 182         }
 183
 184         if (!*argv) {
 185                 noargv[0] = ".";
 186                 noargv[1] = NULL;
 187                 argv = __UNCONST(noargv);
 188         }
 189
 190         if (!gkmflag)
 191                 (void)getbsize(NULL, &blocksize);
 192         blocksize /= 512;
 193
 194         if ((fts = fts_open(argv, ftsoptions, NULL)) == NULL)
 195                 err(1, "fts_open `%s'", *argv);
 196
 197         for (rval = 0; (p = fts_read(fts)) != NULL;) {
 198                 if (nflag) {
 199                         switch (p->fts_info) {
 200                         case FTS_NS:
 201                         case FTS_SLNONE:
 202                                 /* nothing */
 203                                 break;
 204                         default:
 205                                 if (p->fts_statp->st_flags & UF_NODUMP) {
 206                                         fts_set(fts, p, FTS_SKIP);
 207                                         continue;
 208                                 }
 209                         }
 210                 }
 211                 switch (p->fts_info) {
 212                 case FTS_D:                     /* Ignore. */
 213                         break;
 214                 case FTS_DP:
 215                         p->fts_parent->fts_number +=
 216                             p->fts_number += COUNT;
 217                         if (cflag)
 218                                 totalblocks += COUNT;
 219                         /*
 220                          * If listing each directory, or not listing files
 221                          * or directories and this is post-order of the
 222                          * root of a traversal, display the total.
 223                          */
 224                         if (p->fts_level <= depth
 225                             || (!listfiles && !p->fts_level))
 226                                 prstat(p->fts_path, p->fts_number);
 227                         break;
 228                 case FTS_DC:                    /* Ignore. */
 229                         break;
 230                 case FTS_DNR:                   /* Warn, continue. */
 231                 case FTS_ERR:
 232                 case FTS_NS:
 233                         warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
 234                         rval = 1;
 235                         break;
 236                 default:
 237                         if (p->fts_statp->st_nlink > 1 &&
 238                             linkchk(p->fts_statp->st_dev, p->fts_statp->st_ino))
 239                                 break;
 240                         /*
 241                          * If listing each file, or a non-directory file was
 242                          * the root of a traversal, display the total.
 243                          */
 244                         if (listfiles || !p->fts_level)
 245                                 prstat(p->fts_path, COUNT);
 246                         p->fts_parent->fts_number += COUNT;
 247                         if (cflag)
 248                                 totalblocks += COUNT;
 249                 }
 250         }
 251         if (errno)
 252                 err(1, "fts_read");
 253         if (cflag)
 254                 prstat("total", totalblocks);
 255         exit(rval);
 256 }
 257
 258 static void
 259 prstat(const char *fname, int64_t blocks)
 260 {
 261         if (iflag) {
 262                 (void)printf("%" PRId64 "\t%s\n", blocks, fname);
 263                 return;
 264         }
 265
 266         if (hflag) {
 267                 char buf[5];
 268                 int64_t sz = blocks * 512;
 269
 270                 humanize_number(buf, sizeof(buf), sz, "", HN_AUTOSCALE,
 271                     HN_B | HN_NOSPACE | HN_DECIMAL);
 272
 273                 (void)printf("%s\t%s\n", buf, fname);
 274         } else
 275                 (void)printf("%" PRId64 "\t%s\n",
 276                     howmany(blocks, (int64_t)blocksize),
 277                     fname);
 278 }
 279
 280 static int
 281 linkchk(dev_t dev, ino_t ino)
 282 {
 283         static struct entry {
 284                 dev_t   dev;
 285                 ino_t   ino;
 286         } *htable;
 287         static int htshift;  /* log(allocated size) */
 288         static int htmask;   /* allocated size - 1 */
 289         static int htused;   /* 2*number of insertions */
 290         static int sawzero;  /* Whether zero is in table or not */
 291         int h, h2;
 292         uint64_t tmp;
 293         /* this constant is (1<<64)/((1+sqrt(5))/2)
 294          * aka (word size)/(golden ratio)
 295          */
 296         const uint64_t HTCONST = 11400714819323198485ULL;
 297         const int HTBITS = CHAR_BIT * sizeof(tmp);
 298
 299         /* Never store zero in hashtable */
 300         if (dev == 0 && ino == 0) {
 301                 h = sawzero;
 302                 sawzero = 1;
 303                 return h;
 304         }
 305
 306         /* Extend hash table if necessary, keep load under 0.5 */
 307         if (htused<<1 >= htmask) {
 308                 struct entry *ohtable;
 309
 310                 if (!htable)
 311                         htshift = 10;   /* starting hashtable size */
 312                 else
 313                         htshift++;   /* exponential hashtable growth */
 314
 315                 htmask  = (1 << htshift) - 1;
 316                 htused = 0;
 317
 318                 ohtable = htable;
 319                 htable = calloc(htmask+1, sizeof(*htable));
 320                 if (!htable)
 321                         err(1, "calloc");
 322
 323                 /* populate newly allocated hashtable */
 324                 if (ohtable) {
 325                         int i;
 326                         for (i = 0; i <= htmask>>1; i++)
 327                                 if (ohtable[i].ino || ohtable[i].dev)
 328                                         linkchk(ohtable[i].dev, ohtable[i].ino);
 329                         free(ohtable);
 330                 }
 331         }
 332
 333         /* multiplicative hashing */
 334         tmp = dev;
 335         tmp <<= HTBITS>>1;
 336         tmp |=  ino;
 337         tmp *= HTCONST;
 338         h  = tmp >> (HTBITS - htshift);
 339         h2 = 1 | ( tmp >> (HTBITS - (htshift<<1) - 1)); /* must be odd */
 340
 341         /* open address hashtable search with double hash probing */
 342         while (htable[h].ino || htable[h].dev) {
 343                 if ((htable[h].ino == ino) && (htable[h].dev == dev))
 344                         return 1;
 345                 h = (h + h2) & htmask;
 346         }
 347
 348         /* Insert the current entry into hashtable */
 349         htable[h].dev = dev;
 350         htable[h].ino = ino;
 351         htused++;
 352         return 0;
 353 }
 354
 355 static void
 356 usage(void)
 357 {
 358
 359         (void)fprintf(stderr,
 360                 "usage: du [-H | -L | -P] [-a | -d depth | -s] [-cghikmnrx] [file ...]\n");
 361         exit(1);
 362 }