xref: /minix/usr.bin/du/du.c (revision 84d9c625)
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
main(int argc,char * argv[])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
prstat(const char * fname,int64_t blocks)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
linkchk(dev_t dev,ino_t ino)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
usage(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 }
363