xref: /openbsd/usr.bin/du/du.c (revision f6aab3d8)
1 /*	$OpenBSD: du.c,v 1.33 2022/12/04 23:50:48 cheloha Exp $	*/
2 /*	$NetBSD: du.c,v 1.11 1996/10/18 07:20:35 thorpej Exp $	*/
3 
4 /*
5  * Copyright (c) 1989, 1993, 1994
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Chris Newcomb.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/types.h>
37 #include <sys/stat.h>
38 
39 #include <dirent.h>
40 #include <err.h>
41 #include <errno.h>
42 #include <fts.h>
43 #include <limits.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <sys/tree.h>
48 #include <unistd.h>
49 #include <util.h>
50 
51 
52 int	 linkchk(FTSENT *);
53 void	 prtout(int64_t, char *, int);
54 void	 usage(void);
55 
56 int
57 main(int argc, char *argv[])
58 {
59 	FTS *fts;
60 	FTSENT *p;
61 	long blocksize;
62 	int64_t totalblocks;
63 	int ftsoptions, listfiles, maxdepth;
64 	int Hflag, Lflag, cflag, hflag, kflag;
65 	int ch, notused, rval;
66 	char **save;
67 	const char *errstr;
68 
69 	if (pledge("stdio rpath", NULL) == -1)
70 		err(1, "pledge");
71 
72 	save = argv;
73 	Hflag = Lflag = cflag = hflag = kflag = listfiles = 0;
74 	totalblocks = 0;
75 	ftsoptions = FTS_PHYSICAL;
76 	maxdepth = -1;
77 	while ((ch = getopt(argc, argv, "HLPacd:hkrsx")) != -1)
78 		switch (ch) {
79 		case 'H':
80 			Hflag = 1;
81 			Lflag = 0;
82 			break;
83 		case 'L':
84 			Lflag = 1;
85 			Hflag = 0;
86 			break;
87 		case 'P':
88 			Hflag = Lflag = 0;
89 			break;
90 		case 'a':
91 			listfiles = 1;
92 			break;
93 		case 'c':
94 			cflag = 1;
95 			break;
96 		case 'd':
97 			maxdepth = strtonum(optarg, 0, INT_MAX, &errstr);
98 			if (errstr) {
99 				warnx("max depth %s: %s", optarg, errstr);
100 				usage();
101 			}
102 			break;
103 		case 'h':
104 			hflag = 1;
105 			kflag = 0;
106 			break;
107 		case 'k':
108 			kflag = 1;
109 			hflag = 0;
110 			break;
111 		case 's':
112 			maxdepth = 0;
113 			break;
114 		case 'r':
115 			break;
116 		case 'x':
117 			ftsoptions |= FTS_XDEV;
118 			break;
119 		default:
120 			usage();
121 		}
122 	argc -= optind;
123 	argv += optind;
124 
125 	/*
126 	 * XXX
127 	 * Because of the way that fts(3) works, logical walks will not count
128 	 * the blocks actually used by symbolic links.  We rationalize this by
129 	 * noting that users computing logical sizes are likely to do logical
130 	 * copies, so not counting the links is correct.  The real reason is
131 	 * that we'd have to re-implement the kernel's symbolic link traversing
132 	 * algorithm to get this right.  If, for example, you have relative
133 	 * symbolic links referencing other relative symbolic links, it gets
134 	 * very nasty, very fast.  The bottom line is that it's documented in
135 	 * the man page, so it's a feature.
136 	 */
137 	if (Hflag)
138 		ftsoptions |= FTS_COMFOLLOW;
139 	if (Lflag) {
140 		ftsoptions &= ~FTS_PHYSICAL;
141 		ftsoptions |= FTS_LOGICAL;
142 	}
143 
144 	if (maxdepth == -1)
145 		maxdepth = INT_MAX;
146 
147 	if (!*argv) {
148 		argv = save;
149 		argv[0] = ".";
150 		argv[1] = NULL;
151 	}
152 
153 	if (hflag)
154 		blocksize = 512;
155 	else if (kflag)
156 		blocksize = 1024;
157 	else
158 		(void)getbsize(&notused, &blocksize);
159 	blocksize /= 512;
160 
161 	if ((fts = fts_open(argv, ftsoptions, NULL)) == NULL)
162 		err(1, "fts_open");
163 
164 	for (rval = 0; (p = fts_read(fts)) != NULL;)
165 		switch (p->fts_info) {
166 		case FTS_D:			/* Ignore. */
167 			break;
168 		case FTS_DP:
169 			p->fts_parent->fts_number +=
170 			    p->fts_number += p->fts_statp->st_blocks;
171 			if (cflag)
172 				totalblocks += p->fts_statp->st_blocks;
173 			/*
174 			 * If listing each directory, or not listing files
175 			 * or directories and this is post-order of the
176 			 * root of a traversal, display the total.
177 			 */
178 			if (p->fts_level <= maxdepth)
179 				prtout(howmany(p->fts_number,
180 				    (unsigned long)blocksize), p->fts_path,
181 				    hflag);
182 			break;
183 		case FTS_DC:			/* Ignore. */
184 			break;
185 		case FTS_DNR:			/* Warn, continue. */
186 		case FTS_ERR:
187 		case FTS_NS:
188 			warnc(p->fts_errno, "%s", p->fts_path);
189 			rval = 1;
190 			break;
191 		default:
192 			if (p->fts_statp->st_nlink > 1 && linkchk(p))
193 				break;
194 			/*
195 			 * If listing each file, or a non-directory file was
196 			 * the root of a traversal, display the total.
197 			 */
198 			if ((listfiles && p->fts_level <= maxdepth) ||
199 			    p->fts_level == FTS_ROOTLEVEL)
200 				prtout(howmany(p->fts_statp->st_blocks,
201 				    blocksize), p->fts_path, hflag);
202 			p->fts_parent->fts_number += p->fts_statp->st_blocks;
203 			if (cflag)
204 				totalblocks += p->fts_statp->st_blocks;
205 		}
206 	if (errno)
207 		err(1, "fts_read");
208 	if (cflag) {
209 		prtout(howmany(totalblocks, blocksize), "total", hflag);
210 	}
211 	fts_close(fts);
212 	exit(rval);
213 }
214 
215 
216 struct links_entry {
217 	RB_ENTRY(links_entry) entry;
218 	struct links_entry *fnext;
219 	int	 links;
220 	dev_t	 dev;
221 	ino_t	 ino;
222 };
223 
224 static int
225 links_cmp(struct links_entry *e1, struct links_entry *e2)
226 {
227 	if (e1->dev == e2->dev) {
228 		if (e1->ino == e2->ino)
229 			return (0);
230 		else
231 			return (e1->ino < e2->ino ? -1 : 1);
232 	}
233 	else
234 		return (e1->dev < e2->dev ? -1 : 1);
235 }
236 
237 RB_HEAD(ltree, links_entry) links = RB_INITIALIZER(&links);
238 
239 RB_GENERATE_STATIC(ltree, links_entry, entry, links_cmp);
240 
241 
242 int
243 linkchk(FTSENT *p)
244 {
245 	static struct links_entry *free_list = NULL;
246 	static int stop_allocating = 0;
247 	struct links_entry ltmp, *le;
248 	struct stat *st;
249 
250 	st = p->fts_statp;
251 
252 	ltmp.ino = st->st_ino;
253 	ltmp.dev = st->st_dev;
254 
255 	le = RB_FIND(ltree, &links, &ltmp);
256 	if (le != NULL) {
257 		/*
258 		 * Save memory by releasing an entry when we've seen
259 		 * all of it's links.
260 		 */
261 		if (--le->links <= 0) {
262 			RB_REMOVE(ltree, &links, le);
263 			/* Recycle this node through the free list */
264 			if (stop_allocating) {
265 				free(le);
266 			} else {
267 				le->fnext = free_list;
268 				free_list = le;
269 			}
270 		}
271 		return (1);
272 	}
273 
274 	if (stop_allocating)
275 		return (0);
276 
277 	/* Add this entry to the links cache. */
278 	if (free_list != NULL) {
279 		/* Pull a node from the free list if we can. */
280 		le = free_list;
281 		free_list = le->fnext;
282 	} else
283 		/* Malloc one if we have to. */
284 		le = malloc(sizeof(struct links_entry));
285 
286 	if (le == NULL) {
287 		stop_allocating = 1;
288 		warnx("No more memory for tracking hard links");
289 		return (0);
290 	}
291 
292 	le->dev = st->st_dev;
293 	le->ino = st->st_ino;
294 	le->links = st->st_nlink - 1;
295 	le->fnext = NULL;
296 
297 	RB_INSERT(ltree, &links, le);
298 
299 	return (0);
300 }
301 
302 void
303 prtout(int64_t size, char *path, int hflag)
304 {
305 	if (!hflag)
306 		(void)printf("%lld\t%s\n", size, path);
307 	else {
308 		char buf[FMT_SCALED_STRSIZE];
309 
310 		if (fmt_scaled(size * 512, buf) == 0)
311 			(void)printf("%s\t%s\n", buf, path);
312 		else
313 			(void)printf("%lld\t%s\n", size, path);
314 	}
315 }
316 
317 void
318 usage(void)
319 {
320 
321 	(void)fprintf(stderr,
322 	    "usage: du [-achkrsx] [-H | -L | -P] [-d depth] [file ...]\n");
323 	exit(1);
324 }
325