1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
|
/* $NetBSD: ufs.c,v 1.20 1998/03/01 07:15:39 ross Exp $ */
/*-
* Copyright (c) 2002 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Marshall
* Kirk McKusick and Network Associates Laboratories, the Security
* Research Division of Network Associates, Inc. under DARPA/SPAWAR
* contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
* research program
*
* Copyright (c) 1982, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*
* Copyright (c) 1990, 1991 Carnegie Mellon University
* All Rights Reserved.
*
* Author: David Golub
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Stand-alone file reading package.
*/
#include <sys/param.h>
#include <sys/disklabel.h>
#include <sys/time.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ufs/dir.h>
#include <ufs/ffs/fs.h>
#include "stand.h"
#include "string.h"
#ifdef __alpha__
#define COMPAT_UFS /* DUX has old format file systems */
#endif
static int ufs_open(const char *path, struct open_file *f);
static int ufs_write(struct open_file *f, void *buf, size_t size, size_t *resid);
static int ufs_close(struct open_file *f);
static int ufs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
static off_t ufs_seek(struct open_file *f, off_t offset, int where);
static int ufs_stat(struct open_file *f, struct stat *sb);
static int ufs_readdir(struct open_file *f, struct dirent *d);
struct fs_ops ufs_fsops = {
"ufs",
ufs_open,
ufs_close,
ufs_read,
ufs_write,
ufs_seek,
ufs_stat,
ufs_readdir
};
/*
* In-core open file.
*/
struct file {
off_t f_seekp; /* seek pointer */
struct fs *f_fs; /* pointer to super-block */
union dinode {
struct ufs1_dinode di1;
struct ufs2_dinode di2;
} f_di; /* copy of on-disk inode */
int f_nindir[NIADDR];
/* number of blocks mapped by
indirect block at level i */
char *f_blk[NIADDR]; /* buffer for indirect block at
level i */
size_t f_blksize[NIADDR];
/* size of buffer */
ufs2_daddr_t f_blkno[NIADDR];/* disk address of block in buffer */
ufs2_daddr_t f_buf_blkno; /* block number of data block */
char *f_buf; /* buffer for data block */
size_t f_buf_size; /* size of data block */
};
#define DIP(fp, field) \
((fp)->f_fs->fs_magic == FS_UFS1_MAGIC ? \
(fp)->f_di.di1.field : (fp)->f_di.di2.field)
static int read_inode(ino_t, struct open_file *);
static int block_map(struct open_file *, ufs2_daddr_t, ufs2_daddr_t *);
static int buf_read_file(struct open_file *, char **, size_t *);
static int buf_write_file(struct open_file *, char *, size_t *);
static int search_directory(char *, struct open_file *, ino_t *);
/*
* Read a new inode into a file structure.
*/
static int
read_inode(inumber, f)
ino_t inumber;
struct open_file *f;
{
struct file *fp = (struct file *)f->f_fsdata;
struct fs *fs = fp->f_fs;
char *buf;
size_t rsize;
int rc;
if (fs == NULL)
panic("fs == NULL");
/*
* Read inode and save it.
*/
buf = malloc(fs->fs_bsize);
twiddle();
rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
fsbtodb(fs, ino_to_fsba(fs, inumber)), fs->fs_bsize,
buf, &rsize);
if (rc)
goto out;
if (rsize != fs->fs_bsize) {
rc = EIO;
goto out;
}
if (fp->f_fs->fs_magic == FS_UFS1_MAGIC)
fp->f_di.di1 = ((struct ufs1_dinode *)buf)
[ino_to_fsbo(fs, inumber)];
else
fp->f_di.di2 = ((struct ufs2_dinode *)buf)
[ino_to_fsbo(fs, inumber)];
/*
* Clear out the old buffers
*/
{
int level;
for (level = 0; level < NIADDR; level++)
fp->f_blkno[level] = -1;
fp->f_buf_blkno = -1;
}
fp->f_seekp = 0;
out:
free(buf);
return (rc);
}
/*
* Given an offset in a file, find the disk block number that
* contains that block.
*/
static int
block_map(f, file_block, disk_block_p)
struct open_file *f;
ufs2_daddr_t file_block;
ufs2_daddr_t *disk_block_p; /* out */
{
struct file *fp = (struct file *)f->f_fsdata;
struct fs *fs = fp->f_fs;
int level;
int idx;
ufs2_daddr_t ind_block_num;
int rc;
/*
* Index structure of an inode:
*
* di_db[0..NDADDR-1] hold block numbers for blocks
* 0..NDADDR-1
*
* di_ib[0] index block 0 is the single indirect block
* holds block numbers for blocks
* NDADDR .. NDADDR + NINDIR(fs)-1
*
* di_ib[1] index block 1 is the double indirect block
* holds block numbers for INDEX blocks for blocks
* NDADDR + NINDIR(fs) ..
* NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1
*
* di_ib[2] index block 2 is the triple indirect block
* holds block numbers for double-indirect
* blocks for blocks
* NDADDR + NINDIR(fs) + NINDIR(fs)**2 ..
* NDADDR + NINDIR(fs) + NINDIR(fs)**2
* + NINDIR(fs)**3 - 1
*/
if (file_block < NDADDR) {
/* Direct block. */
*disk_block_p = DIP(fp, di_db[file_block]);
return (0);
}
file_block -= NDADDR;
/*
* nindir[0] = NINDIR
* nindir[1] = NINDIR**2
* nindir[2] = NINDIR**3
* etc
*/
for (level = 0; level < NIADDR; level++) {
if (file_block < fp->f_nindir[level])
break;
file_block -= fp->f_nindir[level];
}
if (level == NIADDR) {
/* Block number too high */
return (EFBIG);
}
ind_block_num = DIP(fp, di_ib[level]);
for (; level >= 0; level--) {
if (ind_block_num == 0) {
*disk_block_p = 0; /* missing */
return (0);
}
if (fp->f_blkno[level] != ind_block_num) {
if (fp->f_blk[level] == (char *)0)
fp->f_blk[level] =
malloc(fs->fs_bsize);
twiddle();
rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
fsbtodb(fp->f_fs, ind_block_num),
fs->fs_bsize,
fp->f_blk[level],
&fp->f_blksize[level]);
if (rc)
return (rc);
if (fp->f_blksize[level] != fs->fs_bsize)
return (EIO);
fp->f_blkno[level] = ind_block_num;
}
if (level > 0) {
idx = file_block / fp->f_nindir[level - 1];
file_block %= fp->f_nindir[level - 1];
} else
idx = file_block;
if (fp->f_fs->fs_magic == FS_UFS1_MAGIC)
ind_block_num = ((ufs1_daddr_t *)fp->f_blk[level])[idx];
else
ind_block_num = ((ufs2_daddr_t *)fp->f_blk[level])[idx];
}
*disk_block_p = ind_block_num;
return (0);
}
/*
* Write a portion of a file from an internal buffer.
*/
static int
buf_write_file(f, buf_p, size_p)
struct open_file *f;
char *buf_p;
size_t *size_p; /* out */
{
struct file *fp = (struct file *)f->f_fsdata;
struct fs *fs = fp->f_fs;
long off;
ufs_lbn_t file_block;
ufs2_daddr_t disk_block;
size_t block_size;
int rc;
/*
* Calculate the starting block address and offset.
*/
off = blkoff(fs, fp->f_seekp);
file_block = lblkno(fs, fp->f_seekp);
block_size = sblksize(fs, DIP(fp, di_size), file_block);
rc = block_map(f, file_block, &disk_block);
if (rc)
return (rc);
if (disk_block == 0)
/* Because we can't allocate space on the drive */
return (EFBIG);
/*
* Truncate buffer at end of file, and at the end of
* this block.
*/
if (*size_p > DIP(fp, di_size) - fp->f_seekp)
*size_p = DIP(fp, di_size) - fp->f_seekp;
if (*size_p > block_size - off)
*size_p = block_size - off;
/*
* If we don't entirely occlude the block and it's not
* in memory already, read it in first.
*/
if (((off > 0) || (*size_p + off < block_size)) &&
(file_block != fp->f_buf_blkno)) {
if (fp->f_buf == (char *)0)
fp->f_buf = malloc(fs->fs_bsize);
twiddle();
rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
fsbtodb(fs, disk_block),
block_size, fp->f_buf, &fp->f_buf_size);
if (rc)
return (rc);
fp->f_buf_blkno = file_block;
}
/*
* Copy the user data into the cached block.
*/
bcopy(buf_p, fp->f_buf + off, *size_p);
/*
* Write the block out to storage.
*/
twiddle();
rc = (f->f_dev->dv_strategy)(f->f_devdata, F_WRITE,
fsbtodb(fs, disk_block),
block_size, fp->f_buf, &fp->f_buf_size);
return (rc);
}
/*
* Read a portion of a file into an internal buffer. Return
* the location in the buffer and the amount in the buffer.
*/
static int
buf_read_file(f, buf_p, size_p)
struct open_file *f;
char **buf_p; /* out */
size_t *size_p; /* out */
{
struct file *fp = (struct file *)f->f_fsdata;
struct fs *fs = fp->f_fs;
long off;
ufs_lbn_t file_block;
ufs2_daddr_t disk_block;
size_t block_size;
int rc;
off = blkoff(fs, fp->f_seekp);
file_block = lblkno(fs, fp->f_seekp);
block_size = sblksize(fs, DIP(fp, di_size), file_block);
if (file_block != fp->f_buf_blkno) {
if (fp->f_buf == (char *)0)
fp->f_buf = malloc(fs->fs_bsize);
rc = block_map(f, file_block, &disk_block);
if (rc)
return (rc);
if (disk_block == 0) {
bzero(fp->f_buf, block_size);
fp->f_buf_size = block_size;
} else {
twiddle();
rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
fsbtodb(fs, disk_block),
block_size, fp->f_buf, &fp->f_buf_size);
if (rc)
return (rc);
}
fp->f_buf_blkno = file_block;
}
/*
* Return address of byte in buffer corresponding to
* offset, and size of remainder of buffer after that
* byte.
*/
*buf_p = fp->f_buf + off;
*size_p = block_size - off;
/*
* But truncate buffer at end of file.
*/
if (*size_p > DIP(fp, di_size) - fp->f_seekp)
*size_p = DIP(fp, di_size) - fp->f_seekp;
return (0);
}
/*
* Search a directory for a name and return its
* i_number.
*/
static int
search_directory(name, f, inumber_p)
char *name;
struct open_file *f;
ino_t *inumber_p; /* out */
{
struct file *fp = (struct file *)f->f_fsdata;
struct direct *dp;
struct direct *edp;
char *buf;
size_t buf_size;
int namlen, length;
int rc;
length = strlen(name);
fp->f_seekp = 0;
while (fp->f_seekp < DIP(fp, di_size)) {
rc = buf_read_file(f, &buf, &buf_size);
if (rc)
return (rc);
dp = (struct direct *)buf;
edp = (struct direct *)(buf + buf_size);
while (dp < edp) {
if (dp->d_ino == (ino_t)0)
goto next;
#if BYTE_ORDER == LITTLE_ENDIAN
if (fp->f_fs->fs_maxsymlinklen <= 0)
namlen = dp->d_type;
else
#endif
namlen = dp->d_namlen;
if (namlen == length &&
!strcmp(name, dp->d_name)) {
/* found entry */
*inumber_p = dp->d_ino;
return (0);
}
next:
dp = (struct direct *)((char *)dp + dp->d_reclen);
}
fp->f_seekp += buf_size;
}
return (ENOENT);
}
static int sblock_try[] = SBLOCKSEARCH;
/*
* Open a file.
*/
static int
ufs_open(upath, f)
const char *upath;
struct open_file *f;
{
char *cp, *ncp;
int c;
ino_t inumber, parent_inumber;
struct file *fp;
struct fs *fs;
int i, rc;
size_t buf_size;
int nlinks = 0;
char namebuf[MAXPATHLEN+1];
char *buf = NULL;
char *path = NULL;
/* allocate file system specific data structure */
fp = malloc(sizeof(struct file));
bzero(fp, sizeof(struct file));
f->f_fsdata = (void *)fp;
/* allocate space and read super block */
fs = malloc(SBLOCKSIZE);
fp->f_fs = fs;
twiddle();
/*
* Try reading the superblock in each of its possible locations.
*/
for (i = 0; sblock_try[i] != -1; i++) {
rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
sblock_try[i] / DEV_BSIZE, SBLOCKSIZE,
(char *)fs, &buf_size);
if (rc)
goto out;
if ((fs->fs_magic == FS_UFS1_MAGIC ||
(fs->fs_magic == FS_UFS2_MAGIC &&
fs->fs_sblockloc == sblock_try[i])) &&
buf_size == SBLOCKSIZE &&
fs->fs_bsize <= MAXBSIZE &&
fs->fs_bsize >= sizeof(struct fs))
break;
}
if (sblock_try[i] == -1) {
rc = EINVAL;
goto out;
}
/*
* Calculate indirect block levels.
*/
{
ufs2_daddr_t mult;
int level;
mult = 1;
for (level = 0; level < NIADDR; level++) {
mult *= NINDIR(fs);
fp->f_nindir[level] = mult;
}
}
inumber = ROOTINO;
if ((rc = read_inode(inumber, f)) != 0)
goto out;
cp = path = strdup(upath);
if (path == NULL) {
rc = ENOMEM;
goto out;
}
while (*cp) {
/*
* Remove extra separators
*/
while (*cp == '/')
cp++;
if (*cp == '\0')
break;
/*
* Check that current node is a directory.
*/
if ((DIP(fp, di_mode) & IFMT) != IFDIR) {
rc = ENOTDIR;
goto out;
}
/*
* Get next component of path name.
*/
{
int len = 0;
ncp = cp;
while ((c = *cp) != '\0' && c != '/') {
if (++len > MAXNAMLEN) {
rc = ENOENT;
goto out;
}
cp++;
}
*cp = '\0';
}
/*
* Look up component in current directory.
* Save directory inumber in case we find a
* symbolic link.
*/
parent_inumber = inumber;
rc = search_directory(ncp, f, &inumber);
*cp = c;
if (rc)
goto out;
/*
* Open next component.
*/
if ((rc = read_inode(inumber, f)) != 0)
goto out;
/*
* Check for symbolic link.
*/
if ((DIP(fp, di_mode) & IFMT) == IFLNK) {
int link_len = DIP(fp, di_size);
int len;
len = strlen(cp);
if (link_len + len > MAXPATHLEN ||
++nlinks > MAXSYMLINKS) {
rc = ENOENT;
goto out;
}
bcopy(cp, &namebuf[link_len], len + 1);
if (link_len < fs->fs_maxsymlinklen) {
if (fp->f_fs->fs_magic == FS_UFS1_MAGIC)
cp = (caddr_t)(fp->f_di.di1.di_db);
else
cp = (caddr_t)(fp->f_di.di2.di_db);
bcopy(cp, namebuf, (unsigned) link_len);
} else {
/*
* Read file for symbolic link
*/
size_t buf_size;
ufs2_daddr_t disk_block;
struct fs *fs = fp->f_fs;
if (!buf)
buf = malloc(fs->fs_bsize);
rc = block_map(f, (ufs2_daddr_t)0, &disk_block);
if (rc)
goto out;
twiddle();
rc = (f->f_dev->dv_strategy)(f->f_devdata,
F_READ, fsbtodb(fs, disk_block),
fs->fs_bsize, buf, &buf_size);
if (rc)
goto out;
bcopy((char *)buf, namebuf, (unsigned)link_len);
}
/*
* If relative pathname, restart at parent directory.
* If absolute pathname, restart at root.
*/
cp = namebuf;
if (*cp != '/')
inumber = parent_inumber;
else
inumber = (ino_t)ROOTINO;
if ((rc = read_inode(inumber, f)) != 0)
goto out;
}
}
/*
* Found terminal component.
*/
rc = 0;
fp->f_seekp = 0;
out:
if (buf)
free(buf);
if (path)
free(path);
if (rc) {
if (fp->f_buf)
free(fp->f_buf);
free(fp->f_fs);
free(fp);
}
return (rc);
}
static int
ufs_close(f)
struct open_file *f;
{
struct file *fp = (struct file *)f->f_fsdata;
int level;
f->f_fsdata = (void *)0;
if (fp == (struct file *)0)
return (0);
for (level = 0; level < NIADDR; level++) {
if (fp->f_blk[level])
free(fp->f_blk[level]);
}
if (fp->f_buf)
free(fp->f_buf);
free(fp->f_fs);
free(fp);
return (0);
}
/*
* Copy a portion of a file into kernel memory.
* Cross block boundaries when necessary.
*/
static int
ufs_read(f, start, size, resid)
struct open_file *f;
void *start;
size_t size;
size_t *resid; /* out */
{
struct file *fp = (struct file *)f->f_fsdata;
size_t csize;
char *buf;
size_t buf_size;
int rc = 0;
char *addr = start;
while (size != 0) {
if (fp->f_seekp >= DIP(fp, di_size))
break;
rc = buf_read_file(f, &buf, &buf_size);
if (rc)
break;
csize = size;
if (csize > buf_size)
csize = buf_size;
bcopy(buf, addr, csize);
fp->f_seekp += csize;
addr += csize;
size -= csize;
}
if (resid)
*resid = size;
return (rc);
}
/*
* Write to a portion of an already allocated file.
* Cross block boundaries when necessary. Can not
* extend the file.
*/
static int
ufs_write(f, start, size, resid)
struct open_file *f;
void *start;
size_t size;
size_t *resid; /* out */
{
struct file *fp = (struct file *)f->f_fsdata;
size_t csize;
int rc = 0;
char *addr = start;
csize = size;
while ((size != 0) && (csize != 0)) {
if (fp->f_seekp >= DIP(fp, di_size))
break;
if (csize >= 512) csize = 512; /* XXX */
rc = buf_write_file(f, addr, &csize);
if (rc)
break;
fp->f_seekp += csize;
addr += csize;
size -= csize;
}
if (resid)
*resid = size;
return (rc);
}
static off_t
ufs_seek(f, offset, where)
struct open_file *f;
off_t offset;
int where;
{
struct file *fp = (struct file *)f->f_fsdata;
switch (where) {
case SEEK_SET:
fp->f_seekp = offset;
break;
case SEEK_CUR:
fp->f_seekp += offset;
break;
case SEEK_END:
fp->f_seekp = DIP(fp, di_size) - offset;
break;
default:
errno = EINVAL;
return (-1);
}
return (fp->f_seekp);
}
static int
ufs_stat(f, sb)
struct open_file *f;
struct stat *sb;
{
struct file *fp = (struct file *)f->f_fsdata;
/* only important stuff */
sb->st_mode = DIP(fp, di_mode);
sb->st_uid = DIP(fp, di_uid);
sb->st_gid = DIP(fp, di_gid);
sb->st_size = DIP(fp, di_size);
return (0);
}
static int
ufs_readdir(struct open_file *f, struct dirent *d)
{
struct file *fp = (struct file *)f->f_fsdata;
struct direct *dp;
char *buf;
size_t buf_size;
int error;
/*
* assume that a directory entry will not be split across blocks
*/
again:
if (fp->f_seekp >= DIP(fp, di_size))
return (ENOENT);
error = buf_read_file(f, &buf, &buf_size);
if (error)
return (error);
dp = (struct direct *)buf;
fp->f_seekp += dp->d_reclen;
if (dp->d_ino == (ino_t)0)
goto again;
d->d_type = dp->d_type;
strcpy(d->d_name, dp->d_name);
return (0);
}
|