source: trunk/minix/commands/simple/du.c@ 10

/* du - report on disk usage            Author: Alistair G. Crooks */

/*
 *      du.c            1.1     27/5/87         agc     Joypace Ltd.
 *                      1.2     24 Mar 89       nick@nswitgould.oz
 *                      1.3     31 Mar 89       nick@nswitgould.oz
 *                      1.4     22 Feb 90       meulenbr@cst.prl.philips.nl
 *                      1.5     09 Jul 91       hp@vmars.tuwien.ac.at
 *                      1.6     01 Oct 92       kjb@cs.vu.nl
 *                      1.7     04 Jan 93       bde
 *                      1.8     19 Sep 94       kjb
 *                      1.9     28 Oct 99       kjb
 *
 *      Copyright 1987, Joypace Ltd., London UK. All rights reserved.
 *      This code may be freely distributed, provided that this notice
 *      remains attached.
 *
 *      du - a public domain interpretation of du(1).
 *
 *  1.2:        Fixed bug involving 14 character long filenames
 *  1.3:        Add [-l levels] option to restrict printing.
 *  1.4:        Added processing of multiple arguments
 *  1.5:        Fixed processing of multiple arguments. General cleanup.
 *  1.6:        Use readdir
 *  1.7:        Merged 1.5 and 1.6.
 *              Print totals even for non-dirs at top level.
 *              Count blocks for each dir before printing total for the dir.
 *              Count blocks for all non-special files.
 *              Don't clutter link buffer with directories.
 *  1.8:        Remember all links.
 *  1.9:        Added -x flag to not cross device boundaries.  Type fixes.
 */


#include <sys/types.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <fcntl.h>
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <dirent.h>
#include <minix/config.h>
#include <minix/const.h>

extern char *optarg;
extern int optind;

#define LINELEN         256
#define NR_ALREADY      512

#ifdef S_IFLNK
#define LSTAT lstat
#else
#define LSTAT stat
#endif

typedef struct already {
  struct already *al_next;
  int al_dev;
  ino_t al_inum;
  nlink_t al_nlink;
} ALREADY;

_PROTOTYPE(int main, (int argc, char **argv));
_PROTOTYPE(int makedname, (char *d, char *f, char *out, int outlen));
_PROTOTYPE(int done, (Dev_t dev, Ino_t inum, Nlink_t nlink));
_PROTOTYPE(long dodir, (char *d, int thislev, Dev_t dev));

char *prog;                     /* program name */
char *optstr = "asxdl:";        /* options */
int silent = 0;                 /* silent mode */
int all = 0;                    /* all directory entries mode */
int crosschk = 0;               /* do not cross device boundaries mode */
char *startdir = ".";           /* starting from here */
int levels = 20000;             /* # of directory levels to print */
ALREADY *already[NR_ALREADY];
int alc;


/*
 *      makedname - make the pathname from the directory name, and the
 *      directory entry, placing it in out. If this would overflow,
 *      return 0, otherwise 1.
 */
int makedname(d, f, out, outlen)
char *d;
char *f;
char *out;
int outlen;
{
  char *cp;
  int length;

  length = strlen(f);
  if (strlen(d) + length + 2 > outlen) return(0);
  for (cp = out; *d; *cp++ = *d++);
  if (*(cp - 1) != '/') *cp++ = '/';
  while (length--) *cp++ = *f++;
  *cp = '\0';
  return(1);
}

/*
 *      done - have we encountered (dev, inum) before? Returns 1 for yes,
 *      0 for no, and remembers (dev, inum, nlink).
 */
int done(dev, inum, nlink)
dev_t dev;
ino_t inum;
nlink_t nlink;
{
  register ALREADY **pap, *ap;

  pap = &already[(unsigned) inum % NR_ALREADY];
  while ((ap = *pap) != NULL) {
        if (ap->al_inum == inum && ap->al_dev == dev) {
                if (--ap->al_nlink == 0) {
                        *pap = ap->al_next;
                        free(ap);
                }
                return(1);
        }
        pap = &ap->al_next;
  }
  if ((ap = malloc(sizeof(*ap))) == NULL) {
        fprintf(stderr, "du: Out of memory\n");
        exit(1);
  }
  ap->al_next = NULL;
  ap->al_inum = inum;
  ap->al_dev = dev;
  ap->al_nlink = nlink - 1;
  *pap = ap;
  return(0);
}

int get_block_size(char *dir, struct stat *st)
{
  struct statfs stfs;
  static int fs_block_size = -1, fs_dev = -1;
  int d;

  if(st->st_dev == fs_dev)
        return fs_block_size;

  if((d = open(dir, O_RDONLY)) < 0) {
        perror(dir);
        return 0;
  }

  if(fstatfs(d, &stfs) < 0) {
        perror(dir);
        return 0;
  }

  fs_block_size = stfs.f_bsize;
  fs_dev = st->st_dev;

  return fs_block_size;
}


/*
 *      dodir - process the directory d. Return the long size (in blocks)
 *      of d and its descendants.
 */
long dodir(d, thislev, dev)
char *d;
int thislev;
dev_t dev;
{
  int maybe_print;
  struct stat s;
  long total_kb;
  char dent[LINELEN];
  DIR *dp;
  struct dirent *entry;
  int block_size;

  if (LSTAT(d, &s) < 0) {
        fprintf(stderr,
                "%s: %s: %s\n", prog, d, strerror(errno));
        return 0L;
  }
  if (s.st_dev != dev && dev != 0 && crosschk) return 0;
  block_size = get_block_size(d, &s);
  if(block_size < 1) {
        fprintf(stderr,
                "%s: %s: funny block size found (%d)\n", 
                        prog, d, block_size);
        return 0L;
  }
  total_kb = ((s.st_size + (block_size - 1)) / block_size) * block_size / 1024;
  switch (s.st_mode & S_IFMT) {
    case S_IFDIR:
        /* Directories should not be linked except to "." and "..", so this
         * directory should not already have been done.
         */
        maybe_print = !silent;
        if ((dp = opendir(d)) == NULL) break;
        while ((entry = readdir(dp)) != NULL) {
                if (strcmp(entry->d_name, ".") == 0 ||
                    strcmp(entry->d_name, "..") == 0)
                        continue;
                if (!makedname(d, entry->d_name, dent, sizeof(dent))) continue;
                total_kb += dodir(dent, thislev - 1, s.st_dev);
        }
        closedir(dp);
        break;
    case S_IFBLK:
    case S_IFCHR:
        /* st_size for special files is not related to blocks used. */
        total_kb = 0;
        /* Fall through. */
    default:
        if (s.st_nlink > 1 && done(s.st_dev, s.st_ino, s.st_nlink)) return 0L;
        maybe_print = all;
        break;
  }
  if (thislev >= levels || (maybe_print && thislev >= 0)) {
        printf("%ld\t%s\n", total_kb, d);
  }
  return(total_kb);
}

int main(argc, argv)
int argc;
char **argv;
{
  int c;

  prog = argv[0];
  while ((c = getopt(argc, argv, optstr)) != EOF) switch (c) {
            case 'a':   all = 1;        break;
            case 's':   silent = 1;     break;
            case 'x':
            case 'd':   crosschk = 1;   break;
            case 'l':   levels = atoi(optarg);  break;
            default:
                fprintf(stderr,
                        "Usage: %s [-asx] [-l levels] [startdir]\n", prog);
                exit(1);
        }
  do {
        if (optind < argc) startdir = argv[optind++];
        alc = 0;
        (void) dodir(startdir, levels, 0);
  } while (optind < argc);
  return(0);
}