1/*
2 * Copyright (c) 2002 Networks Associates Technology, Inc.
3 * All rights reserved.
4 *
5 * This software was developed for the FreeBSD Project by Marshall
6 * Kirk McKusick and Network Associates Laboratories, the Security
7 * Research Division of Network Associates, Inc. under DARPA/SPAWAR
8 * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
9 * research program.
10 *
11 * Copyright (c) 1980, 1989, 1993
12 *	The Regents of the University of California.  All rights reserved.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 *    notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 *    notice, this list of conditions and the following disclaimer in the
21 *    documentation and/or other materials provided with the distribution.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39#if 0
40#ifndef lint
41static char sccsid[] = "@(#)mkfs.c	8.11 (Berkeley) 5/3/95";
42#endif /* not lint */
43#endif
44#include <sys/cdefs.h>
45__FBSDID("$FreeBSD: releng/11.0/sbin/newfs/mkfs.c 298906 2016-05-02 00:45:46Z araujo $");
46
47#include <sys/param.h>
48#include <sys/disklabel.h>
49#include <sys/file.h>
50#include <sys/ioctl.h>
51#include <sys/mman.h>
52#include <sys/resource.h>
53#include <sys/stat.h>
54#include <sys/wait.h>
55#include <err.h>
56#include <grp.h>
57#include <limits.h>
58#include <signal.h>
59#include <stdlib.h>
60#include <string.h>
61#include <stdint.h>
62#include <stdio.h>
63#include <time.h>
64#include <unistd.h>
65#include <ufs/ufs/dinode.h>
66#include <ufs/ufs/dir.h>
67#include <ufs/ffs/fs.h>
68#include "newfs.h"
69
70/*
71 * make file system for cylinder-group style file systems
72 */
73#define UMASK		0755
74#define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
75
76static struct	csum *fscs;
77#define	sblock	disk.d_fs
78#define	acg	disk.d_cg
79
80union dinode {
81	struct ufs1_dinode dp1;
82	struct ufs2_dinode dp2;
83};
84#define DIP(dp, field) \
85	((sblock.fs_magic == FS_UFS1_MAGIC) ? \
86	(dp)->dp1.field : (dp)->dp2.field)
87
88static caddr_t iobuf;
89static long iobufsize;
90static ufs2_daddr_t alloc(int size, int mode);
91static int charsperline(void);
92static void clrblock(struct fs *, unsigned char *, int);
93static void fsinit(time_t);
94static int ilog2(int);
95static void initcg(int, time_t);
96static int isblock(struct fs *, unsigned char *, int);
97static void iput(union dinode *, ino_t);
98static int makedir(struct direct *, int);
99static void setblock(struct fs *, unsigned char *, int);
100static void wtfs(ufs2_daddr_t, int, char *);
101static u_int32_t newfs_random(void);
102
103static int
104do_sbwrite(struct uufsd *disk)
105{
106	if (!disk->d_sblock)
107		disk->d_sblock = disk->d_fs.fs_sblockloc / disk->d_bsize;
108	return (pwrite(disk->d_fd, &disk->d_fs, SBLOCKSIZE, (off_t)((part_ofs +
109	    disk->d_sblock) * disk->d_bsize)));
110}
111
112void
113mkfs(struct partition *pp, char *fsys)
114{
115	int fragsperinode, optimalfpg, origdensity, minfpg, lastminfpg;
116	long i, j, csfrags;
117	uint cg;
118	time_t utime;
119	quad_t sizepb;
120	int width;
121	ino_t maxinum;
122	int minfragsperinode;	/* minimum ratio of frags to inodes */
123	char tmpbuf[100];	/* XXX this will break in about 2,500 years */
124	union {
125		struct fs fdummy;
126		char cdummy[SBLOCKSIZE];
127	} dummy;
128#define fsdummy dummy.fdummy
129#define chdummy dummy.cdummy
130
131	/*
132	 * Our blocks == sector size, and the version of UFS we are using is
133	 * specified by Oflag.
134	 */
135	disk.d_bsize = sectorsize;
136	disk.d_ufs = Oflag;
137	if (Rflag)
138		utime = 1000000000;
139	else
140		time(&utime);
141	sblock.fs_old_flags = FS_FLAGS_UPDATED;
142	sblock.fs_flags = 0;
143	if (Uflag)
144		sblock.fs_flags |= FS_DOSOFTDEP;
145	if (Lflag)
146		strlcpy(sblock.fs_volname, volumelabel, MAXVOLLEN);
147	if (Jflag)
148		sblock.fs_flags |= FS_GJOURNAL;
149	if (lflag)
150		sblock.fs_flags |= FS_MULTILABEL;
151	if (tflag)
152		sblock.fs_flags |= FS_TRIM;
153	/*
154	 * Validate the given file system size.
155	 * Verify that its last block can actually be accessed.
156	 * Convert to file system fragment sized units.
157	 */
158	if (fssize <= 0) {
159		printf("preposterous size %jd\n", (intmax_t)fssize);
160		exit(13);
161	}
162	wtfs(fssize - (realsectorsize / DEV_BSIZE), realsectorsize,
163	    (char *)&sblock);
164	/*
165	 * collect and verify the file system density info
166	 */
167	sblock.fs_avgfilesize = avgfilesize;
168	sblock.fs_avgfpdir = avgfilesperdir;
169	if (sblock.fs_avgfilesize <= 0)
170		printf("illegal expected average file size %d\n",
171		    sblock.fs_avgfilesize), exit(14);
172	if (sblock.fs_avgfpdir <= 0)
173		printf("illegal expected number of files per directory %d\n",
174		    sblock.fs_avgfpdir), exit(15);
175
176restart:
177	/*
178	 * collect and verify the block and fragment sizes
179	 */
180	sblock.fs_bsize = bsize;
181	sblock.fs_fsize = fsize;
182	if (!POWEROF2(sblock.fs_bsize)) {
183		printf("block size must be a power of 2, not %d\n",
184		    sblock.fs_bsize);
185		exit(16);
186	}
187	if (!POWEROF2(sblock.fs_fsize)) {
188		printf("fragment size must be a power of 2, not %d\n",
189		    sblock.fs_fsize);
190		exit(17);
191	}
192	if (sblock.fs_fsize < sectorsize) {
193		printf("increasing fragment size from %d to sector size (%d)\n",
194		    sblock.fs_fsize, sectorsize);
195		sblock.fs_fsize = sectorsize;
196	}
197	if (sblock.fs_bsize > MAXBSIZE) {
198		printf("decreasing block size from %d to maximum (%d)\n",
199		    sblock.fs_bsize, MAXBSIZE);
200		sblock.fs_bsize = MAXBSIZE;
201	}
202	if (sblock.fs_bsize < MINBSIZE) {
203		printf("increasing block size from %d to minimum (%d)\n",
204		    sblock.fs_bsize, MINBSIZE);
205		sblock.fs_bsize = MINBSIZE;
206	}
207	if (sblock.fs_fsize > MAXBSIZE) {
208		printf("decreasing fragment size from %d to maximum (%d)\n",
209		    sblock.fs_fsize, MAXBSIZE);
210		sblock.fs_fsize = MAXBSIZE;
211	}
212	if (sblock.fs_bsize < sblock.fs_fsize) {
213		printf("increasing block size from %d to fragment size (%d)\n",
214		    sblock.fs_bsize, sblock.fs_fsize);
215		sblock.fs_bsize = sblock.fs_fsize;
216	}
217	if (sblock.fs_fsize * MAXFRAG < sblock.fs_bsize) {
218		printf(
219		"increasing fragment size from %d to block size / %d (%d)\n",
220		    sblock.fs_fsize, MAXFRAG, sblock.fs_bsize / MAXFRAG);
221		sblock.fs_fsize = sblock.fs_bsize / MAXFRAG;
222	}
223	if (maxbsize == 0)
224		maxbsize = bsize;
225	if (maxbsize < bsize || !POWEROF2(maxbsize)) {
226		sblock.fs_maxbsize = sblock.fs_bsize;
227		printf("Extent size set to %d\n", sblock.fs_maxbsize);
228	} else if (sblock.fs_maxbsize > FS_MAXCONTIG * sblock.fs_bsize) {
229		sblock.fs_maxbsize = FS_MAXCONTIG * sblock.fs_bsize;
230		printf("Extent size reduced to %d\n", sblock.fs_maxbsize);
231	} else {
232		sblock.fs_maxbsize = maxbsize;
233	}
234	/*
235	 * Maxcontig sets the default for the maximum number of blocks
236	 * that may be allocated sequentially. With file system clustering
237	 * it is possible to allocate contiguous blocks up to the maximum
238	 * transfer size permitted by the controller or buffering.
239	 */
240	if (maxcontig == 0)
241		maxcontig = MAX(1, MAXPHYS / bsize);
242	sblock.fs_maxcontig = maxcontig;
243	if (sblock.fs_maxcontig < sblock.fs_maxbsize / sblock.fs_bsize) {
244		sblock.fs_maxcontig = sblock.fs_maxbsize / sblock.fs_bsize;
245		printf("Maxcontig raised to %d\n", sblock.fs_maxbsize);
246	}
247	if (sblock.fs_maxcontig > 1)
248		sblock.fs_contigsumsize = MIN(sblock.fs_maxcontig,FS_MAXCONTIG);
249	sblock.fs_bmask = ~(sblock.fs_bsize - 1);
250	sblock.fs_fmask = ~(sblock.fs_fsize - 1);
251	sblock.fs_qbmask = ~sblock.fs_bmask;
252	sblock.fs_qfmask = ~sblock.fs_fmask;
253	sblock.fs_bshift = ilog2(sblock.fs_bsize);
254	sblock.fs_fshift = ilog2(sblock.fs_fsize);
255	sblock.fs_frag = numfrags(&sblock, sblock.fs_bsize);
256	sblock.fs_fragshift = ilog2(sblock.fs_frag);
257	if (sblock.fs_frag > MAXFRAG) {
258		printf("fragment size %d is still too small (can't happen)\n",
259		    sblock.fs_bsize / MAXFRAG);
260		exit(21);
261	}
262	sblock.fs_fsbtodb = ilog2(sblock.fs_fsize / sectorsize);
263	sblock.fs_size = fssize = dbtofsb(&sblock, fssize);
264	sblock.fs_providersize = dbtofsb(&sblock, mediasize / sectorsize);
265
266	/*
267	 * Before the filesystem is finally initialized, mark it
268	 * as incompletely initialized.
269	 */
270	sblock.fs_magic = FS_BAD_MAGIC;
271
272	if (Oflag == 1) {
273		sblock.fs_sblockloc = SBLOCK_UFS1;
274		sblock.fs_nindir = sblock.fs_bsize / sizeof(ufs1_daddr_t);
275		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs1_dinode);
276		sblock.fs_maxsymlinklen = ((NDADDR + NIADDR) *
277		    sizeof(ufs1_daddr_t));
278		sblock.fs_old_inodefmt = FS_44INODEFMT;
279		sblock.fs_old_cgoffset = 0;
280		sblock.fs_old_cgmask = 0xffffffff;
281		sblock.fs_old_size = sblock.fs_size;
282		sblock.fs_old_rotdelay = 0;
283		sblock.fs_old_rps = 60;
284		sblock.fs_old_nspf = sblock.fs_fsize / sectorsize;
285		sblock.fs_old_cpg = 1;
286		sblock.fs_old_interleave = 1;
287		sblock.fs_old_trackskew = 0;
288		sblock.fs_old_cpc = 0;
289		sblock.fs_old_postblformat = 1;
290		sblock.fs_old_nrpos = 1;
291	} else {
292		sblock.fs_sblockloc = SBLOCK_UFS2;
293		sblock.fs_nindir = sblock.fs_bsize / sizeof(ufs2_daddr_t);
294		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs2_dinode);
295		sblock.fs_maxsymlinklen = ((NDADDR + NIADDR) *
296		    sizeof(ufs2_daddr_t));
297	}
298	sblock.fs_sblkno =
299	    roundup(howmany(sblock.fs_sblockloc + SBLOCKSIZE, sblock.fs_fsize),
300		sblock.fs_frag);
301	sblock.fs_cblkno = sblock.fs_sblkno +
302	    roundup(howmany(SBLOCKSIZE, sblock.fs_fsize), sblock.fs_frag);
303	sblock.fs_iblkno = sblock.fs_cblkno + sblock.fs_frag;
304	sblock.fs_maxfilesize = sblock.fs_bsize * NDADDR - 1;
305	for (sizepb = sblock.fs_bsize, i = 0; i < NIADDR; i++) {
306		sizepb *= NINDIR(&sblock);
307		sblock.fs_maxfilesize += sizepb;
308	}
309
310	/*
311	 * It's impossible to create a snapshot in case that fs_maxfilesize
312	 * is smaller than the fssize.
313	 */
314	if (sblock.fs_maxfilesize < (u_quad_t)fssize) {
315		warnx("WARNING: You will be unable to create snapshots on this "
316		      "file system.  Correct by using a larger blocksize.");
317	}
318
319	/*
320	 * Calculate the number of blocks to put into each cylinder group.
321	 *
322	 * This algorithm selects the number of blocks per cylinder
323	 * group. The first goal is to have at least enough data blocks
324	 * in each cylinder group to meet the density requirement. Once
325	 * this goal is achieved we try to expand to have at least
326	 * MINCYLGRPS cylinder groups. Once this goal is achieved, we
327	 * pack as many blocks into each cylinder group map as will fit.
328	 *
329	 * We start by calculating the smallest number of blocks that we
330	 * can put into each cylinder group. If this is too big, we reduce
331	 * the density until it fits.
332	 */
333	maxinum = (((int64_t)(1)) << 32) - INOPB(&sblock);
334	minfragsperinode = 1 + fssize / maxinum;
335	if (density == 0) {
336		density = MAX(NFPI, minfragsperinode) * fsize;
337	} else if (density < minfragsperinode * fsize) {
338		origdensity = density;
339		density = minfragsperinode * fsize;
340		fprintf(stderr, "density increased from %d to %d\n",
341		    origdensity, density);
342	}
343	origdensity = density;
344	for (;;) {
345		fragsperinode = MAX(numfrags(&sblock, density), 1);
346		if (fragsperinode < minfragsperinode) {
347			bsize <<= 1;
348			fsize <<= 1;
349			printf("Block size too small for a file system %s %d\n",
350			     "of this size. Increasing blocksize to", bsize);
351			goto restart;
352		}
353		minfpg = fragsperinode * INOPB(&sblock);
354		if (minfpg > sblock.fs_size)
355			minfpg = sblock.fs_size;
356		sblock.fs_ipg = INOPB(&sblock);
357		sblock.fs_fpg = roundup(sblock.fs_iblkno +
358		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
359		if (sblock.fs_fpg < minfpg)
360			sblock.fs_fpg = minfpg;
361		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
362		    INOPB(&sblock));
363		sblock.fs_fpg = roundup(sblock.fs_iblkno +
364		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
365		if (sblock.fs_fpg < minfpg)
366			sblock.fs_fpg = minfpg;
367		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
368		    INOPB(&sblock));
369		if (CGSIZE(&sblock) < (unsigned long)sblock.fs_bsize)
370			break;
371		density -= sblock.fs_fsize;
372	}
373	if (density != origdensity)
374		printf("density reduced from %d to %d\n", origdensity, density);
375	/*
376	 * Start packing more blocks into the cylinder group until
377	 * it cannot grow any larger, the number of cylinder groups
378	 * drops below MINCYLGRPS, or we reach the size requested.
379	 * For UFS1 inodes per cylinder group are stored in an int16_t
380	 * so fs_ipg is limited to 2^15 - 1.
381	 */
382	for ( ; sblock.fs_fpg < maxblkspercg; sblock.fs_fpg += sblock.fs_frag) {
383		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
384		    INOPB(&sblock));
385		if (Oflag > 1 || (Oflag == 1 && sblock.fs_ipg <= 0x7fff)) {
386			if (sblock.fs_size / sblock.fs_fpg < MINCYLGRPS)
387				break;
388			if (CGSIZE(&sblock) < (unsigned long)sblock.fs_bsize)
389				continue;
390			if (CGSIZE(&sblock) == (unsigned long)sblock.fs_bsize)
391				break;
392		}
393		sblock.fs_fpg -= sblock.fs_frag;
394		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
395		    INOPB(&sblock));
396		break;
397	}
398	/*
399	 * Check to be sure that the last cylinder group has enough blocks
400	 * to be viable. If it is too small, reduce the number of blocks
401	 * per cylinder group which will have the effect of moving more
402	 * blocks into the last cylinder group.
403	 */
404	optimalfpg = sblock.fs_fpg;
405	for (;;) {
406		sblock.fs_ncg = howmany(sblock.fs_size, sblock.fs_fpg);
407		lastminfpg = roundup(sblock.fs_iblkno +
408		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
409		if (sblock.fs_size < lastminfpg) {
410			printf("Filesystem size %jd < minimum size of %d\n",
411			    (intmax_t)sblock.fs_size, lastminfpg);
412			exit(28);
413		}
414		if (sblock.fs_size % sblock.fs_fpg >= lastminfpg ||
415		    sblock.fs_size % sblock.fs_fpg == 0)
416			break;
417		sblock.fs_fpg -= sblock.fs_frag;
418		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
419		    INOPB(&sblock));
420	}
421	if (optimalfpg != sblock.fs_fpg)
422		printf("Reduced frags per cylinder group from %d to %d %s\n",
423		   optimalfpg, sblock.fs_fpg, "to enlarge last cyl group");
424	sblock.fs_cgsize = fragroundup(&sblock, CGSIZE(&sblock));
425	sblock.fs_dblkno = sblock.fs_iblkno + sblock.fs_ipg / INOPF(&sblock);
426	if (Oflag == 1) {
427		sblock.fs_old_spc = sblock.fs_fpg * sblock.fs_old_nspf;
428		sblock.fs_old_nsect = sblock.fs_old_spc;
429		sblock.fs_old_npsect = sblock.fs_old_spc;
430		sblock.fs_old_ncyl = sblock.fs_ncg;
431	}
432	/*
433	 * fill in remaining fields of the super block
434	 */
435	sblock.fs_csaddr = cgdmin(&sblock, 0);
436	sblock.fs_cssize =
437	    fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
438	fscs = (struct csum *)calloc(1, sblock.fs_cssize);
439	if (fscs == NULL)
440		errx(31, "calloc failed");
441	sblock.fs_sbsize = fragroundup(&sblock, sizeof(struct fs));
442	if (sblock.fs_sbsize > SBLOCKSIZE)
443		sblock.fs_sbsize = SBLOCKSIZE;
444	sblock.fs_minfree = minfree;
445	if (metaspace > 0 && metaspace < sblock.fs_fpg / 2)
446		sblock.fs_metaspace = blknum(&sblock, metaspace);
447	else if (metaspace != -1)
448		/* reserve half of minfree for metadata blocks */
449		sblock.fs_metaspace = blknum(&sblock,
450		    (sblock.fs_fpg * minfree) / 200);
451	if (maxbpg == 0)
452		sblock.fs_maxbpg = MAXBLKPG(sblock.fs_bsize);
453	else
454		sblock.fs_maxbpg = maxbpg;
455	sblock.fs_optim = opt;
456	sblock.fs_cgrotor = 0;
457	sblock.fs_pendingblocks = 0;
458	sblock.fs_pendinginodes = 0;
459	sblock.fs_fmod = 0;
460	sblock.fs_ronly = 0;
461	sblock.fs_state = 0;
462	sblock.fs_clean = 1;
463	sblock.fs_id[0] = (long)utime;
464	sblock.fs_id[1] = newfs_random();
465	sblock.fs_fsmnt[0] = '\0';
466	csfrags = howmany(sblock.fs_cssize, sblock.fs_fsize);
467	sblock.fs_dsize = sblock.fs_size - sblock.fs_sblkno -
468	    sblock.fs_ncg * (sblock.fs_dblkno - sblock.fs_sblkno);
469	sblock.fs_cstotal.cs_nbfree =
470	    fragstoblks(&sblock, sblock.fs_dsize) -
471	    howmany(csfrags, sblock.fs_frag);
472	sblock.fs_cstotal.cs_nffree =
473	    fragnum(&sblock, sblock.fs_size) +
474	    (fragnum(&sblock, csfrags) > 0 ?
475	     sblock.fs_frag - fragnum(&sblock, csfrags) : 0);
476	sblock.fs_cstotal.cs_nifree = sblock.fs_ncg * sblock.fs_ipg - ROOTINO;
477	sblock.fs_cstotal.cs_ndir = 0;
478	sblock.fs_dsize -= csfrags;
479	sblock.fs_time = utime;
480	if (Oflag == 1) {
481		sblock.fs_old_time = utime;
482		sblock.fs_old_dsize = sblock.fs_dsize;
483		sblock.fs_old_csaddr = sblock.fs_csaddr;
484		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
485		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
486		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
487		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
488	}
489
490	/*
491	 * Dump out summary information about file system.
492	 */
493#	define B2MBFACTOR (1 / (1024.0 * 1024.0))
494	printf("%s: %.1fMB (%jd sectors) block size %d, fragment size %d\n",
495	    fsys, (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
496	    (intmax_t)fsbtodb(&sblock, sblock.fs_size), sblock.fs_bsize,
497	    sblock.fs_fsize);
498	printf("\tusing %d cylinder groups of %.2fMB, %d blks, %d inodes.\n",
499	    sblock.fs_ncg, (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
500	    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
501	if (sblock.fs_flags & FS_DOSOFTDEP)
502		printf("\twith soft updates\n");
503#	undef B2MBFACTOR
504
505	if (Eflag && !Nflag) {
506		printf("Erasing sectors [%jd...%jd]\n",
507		    sblock.fs_sblockloc / disk.d_bsize,
508		    fsbtodb(&sblock, sblock.fs_size) - 1);
509		berase(&disk, sblock.fs_sblockloc / disk.d_bsize,
510		    sblock.fs_size * sblock.fs_fsize - sblock.fs_sblockloc);
511	}
512	/*
513	 * Wipe out old UFS1 superblock(s) if necessary.
514	 */
515	if (!Nflag && Oflag != 1) {
516		i = bread(&disk, part_ofs + SBLOCK_UFS1 / disk.d_bsize, chdummy, SBLOCKSIZE);
517		if (i == -1)
518			err(1, "can't read old UFS1 superblock: %s", disk.d_error);
519
520		if (fsdummy.fs_magic == FS_UFS1_MAGIC) {
521			fsdummy.fs_magic = 0;
522			bwrite(&disk, part_ofs + SBLOCK_UFS1 / disk.d_bsize,
523			    chdummy, SBLOCKSIZE);
524			for (cg = 0; cg < fsdummy.fs_ncg; cg++) {
525				if (fsbtodb(&fsdummy, cgsblock(&fsdummy, cg)) > fssize)
526					break;
527				bwrite(&disk, part_ofs + fsbtodb(&fsdummy,
528				  cgsblock(&fsdummy, cg)), chdummy, SBLOCKSIZE);
529			}
530		}
531	}
532	if (!Nflag)
533		do_sbwrite(&disk);
534	if (Xflag == 1) {
535		printf("** Exiting on Xflag 1\n");
536		exit(0);
537	}
538	if (Xflag == 2)
539		printf("** Leaving BAD MAGIC on Xflag 2\n");
540	else
541		sblock.fs_magic = (Oflag != 1) ? FS_UFS2_MAGIC : FS_UFS1_MAGIC;
542
543	/*
544	 * Now build the cylinders group blocks and
545	 * then print out indices of cylinder groups.
546	 */
547	printf("super-block backups (for fsck_ffs -b #) at:\n");
548	i = 0;
549	width = charsperline();
550	/*
551	 * allocate space for superblock, cylinder group map, and
552	 * two sets of inode blocks.
553	 */
554	if (sblock.fs_bsize < SBLOCKSIZE)
555		iobufsize = SBLOCKSIZE + 3 * sblock.fs_bsize;
556	else
557		iobufsize = 4 * sblock.fs_bsize;
558	if ((iobuf = calloc(1, iobufsize)) == 0) {
559		printf("Cannot allocate I/O buffer\n");
560		exit(38);
561	}
562	/*
563	 * Make a copy of the superblock into the buffer that we will be
564	 * writing out in each cylinder group.
565	 */
566	bcopy((char *)&sblock, iobuf, SBLOCKSIZE);
567	for (cg = 0; cg < sblock.fs_ncg; cg++) {
568		initcg(cg, utime);
569		j = snprintf(tmpbuf, sizeof(tmpbuf), " %jd%s",
570		    (intmax_t)fsbtodb(&sblock, cgsblock(&sblock, cg)),
571		    cg < (sblock.fs_ncg-1) ? "," : "");
572		if (j < 0)
573			tmpbuf[j = 0] = '\0';
574		if (i + j >= width) {
575			printf("\n");
576			i = 0;
577		}
578		i += j;
579		printf("%s", tmpbuf);
580		fflush(stdout);
581	}
582	printf("\n");
583	if (Nflag)
584		exit(0);
585	/*
586	 * Now construct the initial file system,
587	 * then write out the super-block.
588	 */
589	fsinit(utime);
590	if (Oflag == 1) {
591		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
592		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
593		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
594		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
595	}
596	if (Xflag == 3) {
597		printf("** Exiting on Xflag 3\n");
598		exit(0);
599	}
600	if (!Nflag) {
601		do_sbwrite(&disk);
602		/*
603		 * For UFS1 filesystems with a blocksize of 64K, the first
604		 * alternate superblock resides at the location used for
605		 * the default UFS2 superblock. As there is a valid
606		 * superblock at this location, the boot code will use
607		 * it as its first choice. Thus we have to ensure that
608		 * all of its statistcs on usage are correct.
609		 */
610		if (Oflag == 1 && sblock.fs_bsize == 65536)
611			wtfs(fsbtodb(&sblock, cgsblock(&sblock, 0)),
612			    sblock.fs_bsize, (char *)&sblock);
613	}
614	for (i = 0; i < sblock.fs_cssize; i += sblock.fs_bsize)
615		wtfs(fsbtodb(&sblock, sblock.fs_csaddr + numfrags(&sblock, i)),
616			MIN(sblock.fs_cssize - i, sblock.fs_bsize),
617			((char *)fscs) + i);
618	/*
619	 * Update information about this partition in pack
620	 * label, to that it may be updated on disk.
621	 */
622	if (pp != NULL) {
623		pp->p_fstype = FS_BSDFFS;
624		pp->p_fsize = sblock.fs_fsize;
625		pp->p_frag = sblock.fs_frag;
626		pp->p_cpg = sblock.fs_fpg;
627	}
628}
629
630/*
631 * Initialize a cylinder group.
632 */
633void
634initcg(int cylno, time_t utime)
635{
636	long blkno, start;
637	uint i, j, d, dlower, dupper;
638	ufs2_daddr_t cbase, dmax;
639	struct ufs1_dinode *dp1;
640	struct ufs2_dinode *dp2;
641	struct csum *cs;
642
643	/*
644	 * Determine block bounds for cylinder group.
645	 * Allow space for super block summary information in first
646	 * cylinder group.
647	 */
648	cbase = cgbase(&sblock, cylno);
649	dmax = cbase + sblock.fs_fpg;
650	if (dmax > sblock.fs_size)
651		dmax = sblock.fs_size;
652	dlower = cgsblock(&sblock, cylno) - cbase;
653	dupper = cgdmin(&sblock, cylno) - cbase;
654	if (cylno == 0)
655		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
656	cs = &fscs[cylno];
657	memset(&acg, 0, sblock.fs_cgsize);
658	acg.cg_time = utime;
659	acg.cg_magic = CG_MAGIC;
660	acg.cg_cgx = cylno;
661	acg.cg_niblk = sblock.fs_ipg;
662	acg.cg_initediblk = MIN(sblock.fs_ipg, 2 * INOPB(&sblock));
663	acg.cg_ndblk = dmax - cbase;
664	if (sblock.fs_contigsumsize > 0)
665		acg.cg_nclusterblks = acg.cg_ndblk / sblock.fs_frag;
666	start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
667	if (Oflag == 2) {
668		acg.cg_iusedoff = start;
669	} else {
670		acg.cg_old_ncyl = sblock.fs_old_cpg;
671		acg.cg_old_time = acg.cg_time;
672		acg.cg_time = 0;
673		acg.cg_old_niblk = acg.cg_niblk;
674		acg.cg_niblk = 0;
675		acg.cg_initediblk = 0;
676		acg.cg_old_btotoff = start;
677		acg.cg_old_boff = acg.cg_old_btotoff +
678		    sblock.fs_old_cpg * sizeof(int32_t);
679		acg.cg_iusedoff = acg.cg_old_boff +
680		    sblock.fs_old_cpg * sizeof(u_int16_t);
681	}
682	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
683	acg.cg_nextfreeoff = acg.cg_freeoff + howmany(sblock.fs_fpg, CHAR_BIT);
684	if (sblock.fs_contigsumsize > 0) {
685		acg.cg_clustersumoff =
686		    roundup(acg.cg_nextfreeoff, sizeof(u_int32_t));
687		acg.cg_clustersumoff -= sizeof(u_int32_t);
688		acg.cg_clusteroff = acg.cg_clustersumoff +
689		    (sblock.fs_contigsumsize + 1) * sizeof(u_int32_t);
690		acg.cg_nextfreeoff = acg.cg_clusteroff +
691		    howmany(fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
692	}
693	if (acg.cg_nextfreeoff > (unsigned)sblock.fs_cgsize) {
694		printf("Panic: cylinder group too big\n");
695		exit(37);
696	}
697	acg.cg_cs.cs_nifree += sblock.fs_ipg;
698	if (cylno == 0)
699		for (i = 0; i < (long)ROOTINO; i++) {
700			setbit(cg_inosused(&acg), i);
701			acg.cg_cs.cs_nifree--;
702		}
703	if (cylno > 0) {
704		/*
705		 * In cylno 0, beginning space is reserved
706		 * for boot and super blocks.
707		 */
708		for (d = 0; d < dlower; d += sblock.fs_frag) {
709			blkno = d / sblock.fs_frag;
710			setblock(&sblock, cg_blksfree(&acg), blkno);
711			if (sblock.fs_contigsumsize > 0)
712				setbit(cg_clustersfree(&acg), blkno);
713			acg.cg_cs.cs_nbfree++;
714		}
715	}
716	if ((i = dupper % sblock.fs_frag)) {
717		acg.cg_frsum[sblock.fs_frag - i]++;
718		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
719			setbit(cg_blksfree(&acg), dupper);
720			acg.cg_cs.cs_nffree++;
721		}
722	}
723	for (d = dupper; d + sblock.fs_frag <= acg.cg_ndblk;
724	     d += sblock.fs_frag) {
725		blkno = d / sblock.fs_frag;
726		setblock(&sblock, cg_blksfree(&acg), blkno);
727		if (sblock.fs_contigsumsize > 0)
728			setbit(cg_clustersfree(&acg), blkno);
729		acg.cg_cs.cs_nbfree++;
730	}
731	if (d < acg.cg_ndblk) {
732		acg.cg_frsum[acg.cg_ndblk - d]++;
733		for (; d < acg.cg_ndblk; d++) {
734			setbit(cg_blksfree(&acg), d);
735			acg.cg_cs.cs_nffree++;
736		}
737	}
738	if (sblock.fs_contigsumsize > 0) {
739		int32_t *sump = cg_clustersum(&acg);
740		u_char *mapp = cg_clustersfree(&acg);
741		int map = *mapp++;
742		int bit = 1;
743		int run = 0;
744
745		for (i = 0; i < acg.cg_nclusterblks; i++) {
746			if ((map & bit) != 0)
747				run++;
748			else if (run != 0) {
749				if (run > sblock.fs_contigsumsize)
750					run = sblock.fs_contigsumsize;
751				sump[run]++;
752				run = 0;
753			}
754			if ((i & (CHAR_BIT - 1)) != CHAR_BIT - 1)
755				bit <<= 1;
756			else {
757				map = *mapp++;
758				bit = 1;
759			}
760		}
761		if (run != 0) {
762			if (run > sblock.fs_contigsumsize)
763				run = sblock.fs_contigsumsize;
764			sump[run]++;
765		}
766	}
767	*cs = acg.cg_cs;
768	/*
769	 * Write out the duplicate super block, the cylinder group map
770	 * and two blocks worth of inodes in a single write.
771	 */
772	start = MAX(sblock.fs_bsize, SBLOCKSIZE);
773	bcopy((char *)&acg, &iobuf[start], sblock.fs_cgsize);
774	start += sblock.fs_bsize;
775	dp1 = (struct ufs1_dinode *)(&iobuf[start]);
776	dp2 = (struct ufs2_dinode *)(&iobuf[start]);
777	for (i = 0; i < acg.cg_initediblk; i++) {
778		if (sblock.fs_magic == FS_UFS1_MAGIC) {
779			dp1->di_gen = newfs_random();
780			dp1++;
781		} else {
782			dp2->di_gen = newfs_random();
783			dp2++;
784		}
785	}
786	wtfs(fsbtodb(&sblock, cgsblock(&sblock, cylno)), iobufsize, iobuf);
787	/*
788	 * For the old file system, we have to initialize all the inodes.
789	 */
790	if (Oflag == 1) {
791		for (i = 2 * sblock.fs_frag;
792		     i < sblock.fs_ipg / INOPF(&sblock);
793		     i += sblock.fs_frag) {
794			dp1 = (struct ufs1_dinode *)(&iobuf[start]);
795			for (j = 0; j < INOPB(&sblock); j++) {
796				dp1->di_gen = newfs_random();
797				dp1++;
798			}
799			wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno) + i),
800			    sblock.fs_bsize, &iobuf[start]);
801		}
802	}
803}
804
805/*
806 * initialize the file system
807 */
808#define ROOTLINKCNT 3
809
810static struct direct root_dir[] = {
811	{ ROOTINO, sizeof(struct direct), DT_DIR, 1, "." },
812	{ ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
813	{ ROOTINO + 1, sizeof(struct direct), DT_DIR, 5, ".snap" },
814};
815
816#define SNAPLINKCNT 2
817
818static struct direct snap_dir[] = {
819	{ ROOTINO + 1, sizeof(struct direct), DT_DIR, 1, "." },
820	{ ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
821};
822
823void
824fsinit(time_t utime)
825{
826	union dinode node;
827	struct group *grp;
828	gid_t gid;
829	int entries;
830
831	memset(&node, 0, sizeof node);
832	if ((grp = getgrnam("operator")) != NULL) {
833		gid = grp->gr_gid;
834	} else {
835		warnx("Cannot retrieve operator gid, using gid 0.");
836		gid = 0;
837	}
838	entries = (nflag) ? ROOTLINKCNT - 1: ROOTLINKCNT;
839	if (sblock.fs_magic == FS_UFS1_MAGIC) {
840		/*
841		 * initialize the node
842		 */
843		node.dp1.di_atime = utime;
844		node.dp1.di_mtime = utime;
845		node.dp1.di_ctime = utime;
846		/*
847		 * create the root directory
848		 */
849		node.dp1.di_mode = IFDIR | UMASK;
850		node.dp1.di_nlink = entries;
851		node.dp1.di_size = makedir(root_dir, entries);
852		node.dp1.di_db[0] = alloc(sblock.fs_fsize, node.dp1.di_mode);
853		node.dp1.di_blocks =
854		    btodb(fragroundup(&sblock, node.dp1.di_size));
855		wtfs(fsbtodb(&sblock, node.dp1.di_db[0]), sblock.fs_fsize,
856		    iobuf);
857		iput(&node, ROOTINO);
858		if (!nflag) {
859			/*
860			 * create the .snap directory
861			 */
862			node.dp1.di_mode |= 020;
863			node.dp1.di_gid = gid;
864			node.dp1.di_nlink = SNAPLINKCNT;
865			node.dp1.di_size = makedir(snap_dir, SNAPLINKCNT);
866				node.dp1.di_db[0] =
867				    alloc(sblock.fs_fsize, node.dp1.di_mode);
868			node.dp1.di_blocks =
869			    btodb(fragroundup(&sblock, node.dp1.di_size));
870				wtfs(fsbtodb(&sblock, node.dp1.di_db[0]),
871				    sblock.fs_fsize, iobuf);
872			iput(&node, ROOTINO + 1);
873		}
874	} else {
875		/*
876		 * initialize the node
877		 */
878		node.dp2.di_atime = utime;
879		node.dp2.di_mtime = utime;
880		node.dp2.di_ctime = utime;
881		node.dp2.di_birthtime = utime;
882		/*
883		 * create the root directory
884		 */
885		node.dp2.di_mode = IFDIR | UMASK;
886		node.dp2.di_nlink = entries;
887		node.dp2.di_size = makedir(root_dir, entries);
888		node.dp2.di_db[0] = alloc(sblock.fs_fsize, node.dp2.di_mode);
889		node.dp2.di_blocks =
890		    btodb(fragroundup(&sblock, node.dp2.di_size));
891		wtfs(fsbtodb(&sblock, node.dp2.di_db[0]), sblock.fs_fsize,
892		    iobuf);
893		iput(&node, ROOTINO);
894		if (!nflag) {
895			/*
896			 * create the .snap directory
897			 */
898			node.dp2.di_mode |= 020;
899			node.dp2.di_gid = gid;
900			node.dp2.di_nlink = SNAPLINKCNT;
901			node.dp2.di_size = makedir(snap_dir, SNAPLINKCNT);
902				node.dp2.di_db[0] =
903				    alloc(sblock.fs_fsize, node.dp2.di_mode);
904			node.dp2.di_blocks =
905			    btodb(fragroundup(&sblock, node.dp2.di_size));
906				wtfs(fsbtodb(&sblock, node.dp2.di_db[0]),
907				    sblock.fs_fsize, iobuf);
908			iput(&node, ROOTINO + 1);
909		}
910	}
911}
912
913/*
914 * construct a set of directory entries in "iobuf".
915 * return size of directory.
916 */
917int
918makedir(struct direct *protodir, int entries)
919{
920	char *cp;
921	int i, spcleft;
922
923	spcleft = DIRBLKSIZ;
924	memset(iobuf, 0, DIRBLKSIZ);
925	for (cp = iobuf, i = 0; i < entries - 1; i++) {
926		protodir[i].d_reclen = DIRSIZ(0, &protodir[i]);
927		memmove(cp, &protodir[i], protodir[i].d_reclen);
928		cp += protodir[i].d_reclen;
929		spcleft -= protodir[i].d_reclen;
930	}
931	protodir[i].d_reclen = spcleft;
932	memmove(cp, &protodir[i], DIRSIZ(0, &protodir[i]));
933	return (DIRBLKSIZ);
934}
935
936/*
937 * allocate a block or frag
938 */
939ufs2_daddr_t
940alloc(int size, int mode)
941{
942	int i, blkno, frag;
943	uint d;
944
945	bread(&disk, part_ofs + fsbtodb(&sblock, cgtod(&sblock, 0)), (char *)&acg,
946	    sblock.fs_cgsize);
947	if (acg.cg_magic != CG_MAGIC) {
948		printf("cg 0: bad magic number\n");
949		exit(38);
950	}
951	if (acg.cg_cs.cs_nbfree == 0) {
952		printf("first cylinder group ran out of space\n");
953		exit(39);
954	}
955	for (d = 0; d < acg.cg_ndblk; d += sblock.fs_frag)
956		if (isblock(&sblock, cg_blksfree(&acg), d / sblock.fs_frag))
957			goto goth;
958	printf("internal error: can't find block in cyl 0\n");
959	exit(40);
960goth:
961	blkno = fragstoblks(&sblock, d);
962	clrblock(&sblock, cg_blksfree(&acg), blkno);
963	if (sblock.fs_contigsumsize > 0)
964		clrbit(cg_clustersfree(&acg), blkno);
965	acg.cg_cs.cs_nbfree--;
966	sblock.fs_cstotal.cs_nbfree--;
967	fscs[0].cs_nbfree--;
968	if (mode & IFDIR) {
969		acg.cg_cs.cs_ndir++;
970		sblock.fs_cstotal.cs_ndir++;
971		fscs[0].cs_ndir++;
972	}
973	if (size != sblock.fs_bsize) {
974		frag = howmany(size, sblock.fs_fsize);
975		fscs[0].cs_nffree += sblock.fs_frag - frag;
976		sblock.fs_cstotal.cs_nffree += sblock.fs_frag - frag;
977		acg.cg_cs.cs_nffree += sblock.fs_frag - frag;
978		acg.cg_frsum[sblock.fs_frag - frag]++;
979		for (i = frag; i < sblock.fs_frag; i++)
980			setbit(cg_blksfree(&acg), d + i);
981	}
982	/* XXX cgwrite(&disk, 0)??? */
983	wtfs(fsbtodb(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize,
984	    (char *)&acg);
985	return ((ufs2_daddr_t)d);
986}
987
988/*
989 * Allocate an inode on the disk
990 */
991void
992iput(union dinode *ip, ino_t ino)
993{
994	ufs2_daddr_t d;
995
996	bread(&disk, part_ofs + fsbtodb(&sblock, cgtod(&sblock, 0)), (char *)&acg,
997	    sblock.fs_cgsize);
998	if (acg.cg_magic != CG_MAGIC) {
999		printf("cg 0: bad magic number\n");
1000		exit(31);
1001	}
1002	acg.cg_cs.cs_nifree--;
1003	setbit(cg_inosused(&acg), ino);
1004	wtfs(fsbtodb(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize,
1005	    (char *)&acg);
1006	sblock.fs_cstotal.cs_nifree--;
1007	fscs[0].cs_nifree--;
1008	if (ino >= (unsigned long)sblock.fs_ipg * sblock.fs_ncg) {
1009		printf("fsinit: inode value out of range (%ju).\n",
1010		    (uintmax_t)ino);
1011		exit(32);
1012	}
1013	d = fsbtodb(&sblock, ino_to_fsba(&sblock, ino));
1014	bread(&disk, part_ofs + d, (char *)iobuf, sblock.fs_bsize);
1015	if (sblock.fs_magic == FS_UFS1_MAGIC)
1016		((struct ufs1_dinode *)iobuf)[ino_to_fsbo(&sblock, ino)] =
1017		    ip->dp1;
1018	else
1019		((struct ufs2_dinode *)iobuf)[ino_to_fsbo(&sblock, ino)] =
1020		    ip->dp2;
1021	wtfs(d, sblock.fs_bsize, (char *)iobuf);
1022}
1023
1024/*
1025 * possibly write to disk
1026 */
1027static void
1028wtfs(ufs2_daddr_t bno, int size, char *bf)
1029{
1030	if (Nflag)
1031		return;
1032	if (bwrite(&disk, part_ofs + bno, bf, size) < 0)
1033		err(36, "wtfs: %d bytes at sector %jd", size, (intmax_t)bno);
1034}
1035
1036/*
1037 * check if a block is available
1038 */
1039static int
1040isblock(struct fs *fs, unsigned char *cp, int h)
1041{
1042	unsigned char mask;
1043
1044	switch (fs->fs_frag) {
1045	case 8:
1046		return (cp[h] == 0xff);
1047	case 4:
1048		mask = 0x0f << ((h & 0x1) << 2);
1049		return ((cp[h >> 1] & mask) == mask);
1050	case 2:
1051		mask = 0x03 << ((h & 0x3) << 1);
1052		return ((cp[h >> 2] & mask) == mask);
1053	case 1:
1054		mask = 0x01 << (h & 0x7);
1055		return ((cp[h >> 3] & mask) == mask);
1056	default:
1057		fprintf(stderr, "isblock bad fs_frag %d\n", fs->fs_frag);
1058		return (0);
1059	}
1060}
1061
1062/*
1063 * take a block out of the map
1064 */
1065static void
1066clrblock(struct fs *fs, unsigned char *cp, int h)
1067{
1068	switch ((fs)->fs_frag) {
1069	case 8:
1070		cp[h] = 0;
1071		return;
1072	case 4:
1073		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
1074		return;
1075	case 2:
1076		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
1077		return;
1078	case 1:
1079		cp[h >> 3] &= ~(0x01 << (h & 0x7));
1080		return;
1081	default:
1082		fprintf(stderr, "clrblock bad fs_frag %d\n", fs->fs_frag);
1083		return;
1084	}
1085}
1086
1087/*
1088 * put a block into the map
1089 */
1090static void
1091setblock(struct fs *fs, unsigned char *cp, int h)
1092{
1093	switch (fs->fs_frag) {
1094	case 8:
1095		cp[h] = 0xff;
1096		return;
1097	case 4:
1098		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
1099		return;
1100	case 2:
1101		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
1102		return;
1103	case 1:
1104		cp[h >> 3] |= (0x01 << (h & 0x7));
1105		return;
1106	default:
1107		fprintf(stderr, "setblock bad fs_frag %d\n", fs->fs_frag);
1108		return;
1109	}
1110}
1111
1112/*
1113 * Determine the number of characters in a
1114 * single line.
1115 */
1116
1117static int
1118charsperline(void)
1119{
1120	int columns;
1121	char *cp;
1122	struct winsize ws;
1123
1124	columns = 0;
1125	if (ioctl(0, TIOCGWINSZ, &ws) != -1)
1126		columns = ws.ws_col;
1127	if (columns == 0 && (cp = getenv("COLUMNS")))
1128		columns = atoi(cp);
1129	if (columns == 0)
1130		columns = 80;	/* last resort */
1131	return (columns);
1132}
1133
1134static int
1135ilog2(int val)
1136{
1137	u_int n;
1138
1139	for (n = 0; n < sizeof(n) * CHAR_BIT; n++)
1140		if (1 << n == val)
1141			return (n);
1142	errx(1, "ilog2: %d is not a power of 2\n", val);
1143}
1144
1145/*
1146 * For the regression test, return predictable random values.
1147 * Otherwise use a true random number generator.
1148 */
1149static u_int32_t
1150newfs_random(void)
1151{
1152	static int nextnum = 1;
1153
1154	if (Rflag)
1155		return (nextnum++);
1156	return (arc4random());
1157}
1158