2 * Copyright (c) 1999,2000 Jonathan Lemon <jlemon@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/lib/libstand/ext2fs.c,v 1.1.2.2 2001/03/05 06:26:07 kris Exp $
30 * The Regents of the University of California. All rights reserved.
32 * This code is derived from software contributed to Berkeley by
33 * The Mach Operating System project at Carnegie-Mellon University.
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
38 * 1. Redistributions of source code must retain the above copyright
39 * notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 * 3. All advertising materials mentioning features or use of this software
44 * must display the following acknowledgement:
45 * This product includes software developed by the University of
46 * California, Berkeley and its contributors.
47 * 4. Neither the name of the University nor the names of its contributors
48 * may be used to endorse or promote products derived from this software
49 * without specific prior written permission.
51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64 * Copyright (c) 1990, 1991 Carnegie Mellon University
65 * All Rights Reserved.
69 * Permission to use, copy, modify and distribute this software and its
70 * documentation is hereby granted, provided that both the copyright
71 * notice and this permission notice appear in all copies of the
72 * software, derivative works or modified versions, and any portions
73 * thereof, and that both notices appear in supporting documentation.
75 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
76 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
77 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
79 * Carnegie Mellon requests users of this software to return to
81 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
82 * School of Computer Science
83 * Carnegie Mellon University
84 * Pittsburgh PA 15213-3890
86 * any improvements or extensions that they make and grant Carnegie the
87 * rights to redistribute these changes.
90 #include <sys/param.h>
95 static int ext2fs_open(const char *path, struct open_file *f);
96 static int ext2fs_close(struct open_file *f);
97 static int ext2fs_read(struct open_file *f, void *buf,
98 size_t size, size_t *resid);
99 static off_t ext2fs_seek(struct open_file *f, off_t offset, int where);
100 static int ext2fs_stat(struct open_file *f, struct stat *sb);
101 static int ext2fs_readdir(struct open_file *f, struct dirent *d);
103 static int dtmap[] = { DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR,
104 DT_BLK, DT_FIFO, DT_SOCK, DT_LNK };
105 #define EXTFTODT(x) (x) > sizeof(dtmap) / sizeof(dtmap[0]) ? \
106 DT_UNKNOWN : dtmap[x]
108 struct fs_ops ext2fs_fsops = {
119 #define EXT2_SBSIZE 1024
120 #define EXT2_SBLOCK (1024 / DEV_BSIZE) /* block offset of superblock */
121 #define EXT2_MAGIC 0xef53
122 #define EXT2_ROOTINO 2
124 #define EXT2_REV0 0 /* original revision of ext2 */
125 #define EXT2_R0_ISIZE 128 /* inode size */
126 #define EXT2_R0_FIRSTINO 11 /* first inode */
128 #define EXT2_MINBSHIFT 10 /* mininum block shift */
129 #define EXT2_MINFSHIFT 10 /* mininum frag shift */
131 #define NDADDR 12 /* # of direct blocks */
132 #define NIADDR 3 /* # of indirect blocks */
135 * file system block to disk address
137 #define fsb_to_db(fs, blk) ((blk) << (fs)->fs_fsbtodb)
140 * inode to block group offset
141 * inode to block group
142 * inode to disk address
143 * inode to block offset
145 #define ino_to_bgo(fs, ino) (((ino) - 1) % (fs)->fs_ipg)
146 #define ino_to_bg(fs, ino) (((ino) - 1) / (fs)->fs_ipg)
147 #define ino_to_db(fs, bg, ino) \
148 fsb_to_db(fs, ((bg)[ino_to_bg(fs, ino)].bg_inotbl + \
149 ino_to_bgo(fs, ino) / (fs)->fs_ipb))
150 #define ino_to_bo(fs, ino) (ino_to_bgo(fs, ino) % (fs)->fs_ipb)
153 ((fs)->fs_bsize / sizeof(u_int32_t))
154 #define lblkno(fs, loc) /* loc / bsize */ \
155 ((loc) >> (fs)->fs_bshift)
156 #define smalllblktosize(fs, blk) /* blk * bsize */ \
157 ((blk) << (fs)->fs_bshift)
158 #define blkoff(fs, loc) /* loc % bsize */ \
159 ((loc) & (fs)->fs_bmask)
160 #define fragroundup(fs, size) /* roundup(size, fsize) */ \
161 (((size) + (fs)->fs_fmask) & ~(fs)->fs_fmask)
162 #define dblksize(fs, dip, lbn) \
163 (((lbn) >= NDADDR || (dip)->di_size >= smalllblktosize(fs, (lbn) + 1)) \
165 : (fragroundup(fs, blkoff(fs, (dip)->di_size))))
168 * superblock describing ext2fs
171 u_int32_t fd_inodes; /* # of inodes */
172 u_int32_t fd_blocks; /* # of blocks */
173 u_int32_t fd_resblk; /* # of reserved blocks */
174 u_int32_t fd_freeblk; /* # of free blocks */
175 u_int32_t fd_freeino; /* # of free inodes */
176 u_int32_t fd_firstblk; /* first data block */
177 u_int32_t fd_bsize; /* block size */
178 u_int32_t fd_fsize; /* frag size */
179 u_int32_t fd_bpg; /* blocks per group */
180 u_int32_t fd_fpg; /* frags per group */
181 u_int32_t fd_ipg; /* inodes per group */
182 u_int32_t fd_mtime; /* mount time */
183 u_int32_t fd_wtime; /* write time */
184 u_int16_t fd_mount; /* # of mounts */
185 int16_t fd_maxmount; /* max # of mounts */
186 u_int16_t fd_magic; /* magic number */
187 u_int16_t fd_state; /* state */
188 u_int16_t fd_eflag; /* error flags */
189 u_int16_t fd_mnrrev; /* minor revision */
190 u_int32_t fd_lastchk; /* last check */
191 u_int32_t fd_chkintvl; /* maximum check interval */
192 u_int32_t fd_os; /* os */
193 u_int32_t fd_revision; /* revision */
194 u_int16_t fd_uid; /* uid for reserved blocks */
195 u_int16_t fd_gid; /* gid for reserved blocks */
197 u_int32_t fd_firstino; /* first non-reserved inode */
198 u_int16_t fd_isize; /* inode size */
199 u_int16_t fd_nblkgrp; /* block group # of superblock */
200 u_int32_t fd_fcompat; /* compatible features */
201 u_int32_t fd_fincompat; /* incompatible features */
202 u_int32_t fd_frocompat; /* read-only compatibilties */
203 u_int8_t fd_uuid[16]; /* volume uuid */
204 char fd_volname[16]; /* volume name */
205 char fd_fsmnt[64]; /* name last mounted on */
206 u_int32_t fd_bitmap; /* compression bitmap */
208 u_int8_t fd_nblkpa; /* # of blocks to preallocate */
209 u_int8_t fd_ndblkpa; /* # of dir blocks to preallocate */
213 int fc_bsize; /* block size */
214 int fc_bshift; /* block shift amount */
215 int fc_bmask; /* block mask */
216 int fc_fsize; /* frag size */
217 int fc_fshift; /* frag shift amount */
218 int fc_fmask; /* frag mask */
219 int fc_isize; /* inode size */
220 int fc_imask; /* inode mask */
221 int fc_firstino; /* first non-reserved inode */
222 int fc_ipb; /* inodes per block */
223 int fc_fsbtodb; /* fsb to ds shift */
227 struct ext2fs_disk fs_fd;
228 char fs_pad[EXT2_SBSIZE - sizeof(struct ext2fs_disk)];
229 struct ext2fs_core fs_fc;
231 #define fs_magic fs_fd.fd_magic
232 #define fs_revision fs_fd.fd_revision
233 #define fs_blocks fs_fd.fd_blocks
234 #define fs_firstblk fs_fd.fd_firstblk
235 #define fs_bpg fs_fd.fd_bpg
236 #define fs_ipg fs_fd.fd_ipg
238 #define fs_bsize fs_fc.fc_bsize
239 #define fs_bshift fs_fc.fc_bshift
240 #define fs_bmask fs_fc.fc_bmask
241 #define fs_fsize fs_fc.fc_fsize
242 #define fs_fshift fs_fc.fc_fshift
243 #define fs_fmask fs_fc.fc_fmask
244 #define fs_isize fs_fc.fc_isize
245 #define fs_imask fs_fc.fc_imask
246 #define fs_firstino fs_fc.fc_firstino
247 #define fs_ipb fs_fc.fc_ipb
248 #define fs_fsbtodb fs_fc.fc_fsbtodb
252 u_int32_t bg_blkmap; /* block bitmap */
253 u_int32_t bg_inomap; /* inode bitmap */
254 u_int32_t bg_inotbl; /* inode table */
255 u_int16_t bg_nfblk; /* # of free blocks */
256 u_int16_t bg_nfino; /* # of free inodes */
257 u_int16_t bg_ndirs; /* # of dirs */
262 u_int16_t di_mode; /* mode */
263 u_int16_t di_uid; /* uid */
264 u_int32_t di_size; /* byte size */
265 u_int32_t di_atime; /* access time */
266 u_int32_t di_ctime; /* creation time */
267 u_int32_t di_mtime; /* modification time */
268 u_int32_t di_dtime; /* deletion time */
269 u_int16_t di_gid; /* gid */
270 u_int16_t di_nlink; /* link count */
271 u_int32_t di_nblk; /* block count */
272 u_int32_t di_flags; /* file flags */
274 u_int32_t di_osdep1; /* os dependent stuff */
276 u_int32_t di_db[NDADDR]; /* direct blocks */
277 u_int32_t di_ib[NIADDR]; /* indirect blocks */
278 u_int32_t di_version; /* version */
279 u_int32_t di_facl; /* file acl */
280 u_int32_t di_dacl; /* dir acl */
281 u_int32_t di_faddr; /* fragment addr */
283 u_int8_t di_frag; /* fragment number */
284 u_int8_t di_fsize; /* fragment size */
288 #define di_shortlink di_db
291 #define EXT2_MAXNAMLEN 255
294 u_int32_t d_ino; /* inode */
295 u_int16_t d_reclen; /* directory entry length */
296 u_int8_t d_namlen; /* name length */
297 u_int8_t d_type; /* file type */
298 char d_name[EXT2_MAXNAMLEN];
302 off_t f_seekp; /* seek pointer */
303 struct ext2fs *f_fs; /* pointer to super-block */
304 struct ext2blkgrp *f_bg; /* pointer to blkgrp map */
305 struct ext2dinode f_di; /* copy of on-disk inode */
306 int f_nindir[NIADDR]; /* number of blocks mapped by
307 indirect block at level i */
308 char *f_blk[NIADDR]; /* buffer for indirect block
310 size_t f_blksize[NIADDR]; /* size of buffer */
311 daddr_t f_blkno[NIADDR]; /* disk address of block in
313 char *f_buf; /* buffer for data block */
314 size_t f_buf_size; /* size of data block */
315 daddr_t f_buf_blkno; /* block number of data block */
319 static int read_inode(ino_t inumber, struct open_file *f);
320 static int block_map(struct open_file *f, daddr_t file_block,
321 daddr_t *disk_block_p);
322 static int buf_read_file(struct open_file *f, char **buf_p,
324 static int search_directory(char *name, struct open_file *f,
331 ext2fs_open(const char *upath, struct open_file *f)
336 ino_t inumber, parent_inumber;
337 int i, len, groups, bg_per_blk, blkgrps, mult;
340 char *cp, *ncp, *path = NULL, *buf = NULL;
341 char namebuf[MAXPATHLEN+1];
344 /* allocate file system specific data structure */
345 fp = malloc(sizeof(struct file));
348 bzero(fp, sizeof(struct file));
349 f->f_fsdata = (void *)fp;
351 /* allocate space and read super block */
352 fs = (struct ext2fs *)malloc(sizeof(*fs));
355 error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
356 EXT2_SBLOCK, EXT2_SBSIZE, (char *)fs, &buf_size);
360 if (buf_size != EXT2_SBSIZE || fs->fs_magic != EXT2_MAGIC) {
366 * compute in-core values for the superblock
368 fs->fs_bshift = EXT2_MINBSHIFT + fs->fs_fd.fd_bsize;
369 fs->fs_bsize = 1 << fs->fs_bshift;
370 fs->fs_bmask = fs->fs_bsize - 1;
372 fs->fs_fshift = EXT2_MINFSHIFT + fs->fs_fd.fd_fsize;
373 fs->fs_fsize = 1 << fs->fs_fshift;
374 fs->fs_fmask = fs->fs_fsize - 1;
376 if (fs->fs_revision == EXT2_REV0) {
377 fs->fs_isize = EXT2_R0_ISIZE;
378 fs->fs_firstino = EXT2_R0_FIRSTINO;
380 fs->fs_isize = fs->fs_fd.fd_isize;
381 fs->fs_firstino = fs->fs_fd.fd_firstino;
383 fs->fs_imask = fs->fs_isize - 1;
384 fs->fs_ipb = fs->fs_bsize / fs->fs_isize;
385 fs->fs_fsbtodb = (fs->fs_bsize / DEV_BSIZE) - 1;
388 * we have to load in the "group descriptors" here
390 groups = howmany(fs->fs_blocks - fs->fs_firstblk, fs->fs_bpg);
391 bg_per_blk = fs->fs_bsize / sizeof(struct ext2blkgrp);
392 blkgrps = howmany(groups, bg_per_blk);
393 len = blkgrps * fs->fs_bsize;
395 fp->f_bg = malloc(len);
397 error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
398 EXT2_SBLOCK + EXT2_SBSIZE / DEV_BSIZE, len,
399 (char *)fp->f_bg, &buf_size);
405 * validation of values? (blocksize, descriptors, etc?)
409 * Calculate indirect block levels.
412 for (i = 0; i < NIADDR; i++) {
414 fp->f_nindir[i] = mult;
417 inumber = EXT2_ROOTINO;
418 if ((error = read_inode(inumber, f)) != 0)
421 path = strdup(upath);
429 * Remove extra separators
437 * Check that current node is a directory.
439 if (! S_ISDIR(fp->f_di.di_mode)) {
445 * Get next component of path name.
450 while ((c = *cp) != '\0' && c != '/') {
451 if (++len > EXT2_MAXNAMLEN) {
460 * Look up component in current directory.
461 * Save directory inumber in case we find a
464 parent_inumber = inumber;
465 error = search_directory(ncp, f, &inumber);
471 * Open next component.
473 if ((error = read_inode(inumber, f)) != 0)
477 * Check for symbolic link.
479 if (S_ISLNK(fp->f_di.di_mode)) {
480 int link_len = fp->f_di.di_size;
484 if (link_len + len > MAXPATHLEN ||
485 ++nlinks > MAXSYMLINKS) {
490 bcopy(cp, &namebuf[link_len], len + 1);
491 if (fp->f_di.di_nblk == 0) {
492 bcopy(fp->f_di.di_shortlink,
496 * Read file for symbolic link
498 struct ext2fs *fs = fp->f_fs;
503 buf = malloc(fs->fs_bsize);
504 error = block_map(f, (daddr_t)0, &disk_block);
509 error = (f->f_dev->dv_strategy)(f->f_devdata,
510 F_READ, fsb_to_db(fs, disk_block),
511 fs->fs_bsize, buf, &buf_size);
515 bcopy((char *)buf, namebuf, link_len);
519 * If relative pathname, restart at parent directory.
520 * If absolute pathname, restart at root.
524 inumber = parent_inumber;
526 inumber = (ino_t)EXT2_ROOTINO;
528 if ((error = read_inode(inumber, f)) != 0)
534 * Found terminal component.
552 * Read a new inode into a file structure.
555 read_inode(ino_t inumber, struct open_file *f)
557 struct file *fp = (struct file *)f->f_fsdata;
558 struct ext2fs *fs = fp->f_fs;
559 struct ext2dinode *dp;
562 int level, error = 0;
565 * Read inode and save it.
567 buf = malloc(fs->fs_bsize);
569 error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
570 ino_to_db(fs, fp->f_bg, inumber), fs->fs_bsize, buf, &rsize);
573 if (rsize != fs->fs_bsize) {
578 dp = (struct ext2dinode *)buf;
579 fp->f_di = dp[ino_to_bo(fs, inumber)];
581 /* clear out old buffers */
582 for (level = 0; level < NIADDR; level++)
583 fp->f_blkno[level] = -1;
584 fp->f_buf_blkno = -1;
592 * Given an offset in a file, find the disk block number that
593 * contains that block.
596 block_map(struct open_file *f, daddr_t file_block, daddr_t *disk_block_p)
598 struct file *fp = (struct file *)f->f_fsdata;
599 struct ext2fs *fs = fp->f_fs;
600 daddr_t ind_block_num;
606 * Index structure of an inode:
608 * di_db[0..NDADDR-1] hold block numbers for blocks
611 * di_ib[0] index block 0 is the single indirect block
612 * holds block numbers for blocks
613 * NDADDR .. NDADDR + NINDIR(fs)-1
615 * di_ib[1] index block 1 is the double indirect block
616 * holds block numbers for INDEX blocks for blocks
617 * NDADDR + NINDIR(fs) ..
618 * NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1
620 * di_ib[2] index block 2 is the triple indirect block
621 * holds block numbers for double-indirect
623 * NDADDR + NINDIR(fs) + NINDIR(fs)**2 ..
624 * NDADDR + NINDIR(fs) + NINDIR(fs)**2
625 * + NINDIR(fs)**3 - 1
628 if (file_block < NDADDR) {
630 *disk_block_p = fp->f_di.di_db[file_block];
634 file_block -= NDADDR;
638 * nindir[1] = NINDIR**2
639 * nindir[2] = NINDIR**3
642 for (level = 0; level < NIADDR; level++) {
643 if (file_block < fp->f_nindir[level])
645 file_block -= fp->f_nindir[level];
647 if (level == NIADDR) {
648 /* Block number too high */
652 ind_block_num = fp->f_di.di_ib[level];
654 for (; level >= 0; level--) {
655 if (ind_block_num == 0) {
656 *disk_block_p = 0; /* missing */
660 if (fp->f_blkno[level] != ind_block_num) {
661 if (fp->f_blk[level] == (char *)0)
663 malloc(fs->fs_bsize);
665 error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
666 fsb_to_db(fp->f_fs, ind_block_num), fs->fs_bsize,
667 fp->f_blk[level], &fp->f_blksize[level]);
670 if (fp->f_blksize[level] != fs->fs_bsize)
672 fp->f_blkno[level] = ind_block_num;
675 ind_p = (daddr_t *)fp->f_blk[level];
678 idx = file_block / fp->f_nindir[level - 1];
679 file_block %= fp->f_nindir[level - 1];
683 ind_block_num = ind_p[idx];
686 *disk_block_p = ind_block_num;
692 * Read a portion of a file into an internal buffer. Return
693 * the location in the buffer and the amount in the buffer.
696 buf_read_file(struct open_file *f, char **buf_p, size_t *size_p)
698 struct file *fp = (struct file *)f->f_fsdata;
699 struct ext2fs *fs = fp->f_fs;
706 off = blkoff(fs, fp->f_seekp);
707 file_block = lblkno(fs, fp->f_seekp);
708 block_size = dblksize(fs, &fp->f_di, file_block);
710 if (file_block != fp->f_buf_blkno) {
711 error = block_map(f, file_block, &disk_block);
715 if (fp->f_buf == (char *)0)
716 fp->f_buf = malloc(fs->fs_bsize);
718 if (disk_block == 0) {
719 bzero(fp->f_buf, block_size);
720 fp->f_buf_size = block_size;
723 error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
724 fsb_to_db(fs, disk_block), block_size,
725 fp->f_buf, &fp->f_buf_size);
729 fp->f_buf_blkno = file_block;
733 * Return address of byte in buffer corresponding to
734 * offset, and size of remainder of buffer after that
737 *buf_p = fp->f_buf + off;
738 *size_p = block_size - off;
741 * But truncate buffer at end of file.
743 if (*size_p > fp->f_di.di_size - fp->f_seekp)
744 *size_p = fp->f_di.di_size - fp->f_seekp;
750 * Search a directory for a name and return its
754 search_directory(char *name, struct open_file *f, ino_t *inumber_p)
756 struct file *fp = (struct file *)f->f_fsdata;
757 struct ext2dirent *dp, *edp;
763 length = strlen(name);
765 while (fp->f_seekp < fp->f_di.di_size) {
766 error = buf_read_file(f, &buf, &buf_size);
769 dp = (struct ext2dirent *)buf;
770 edp = (struct ext2dirent *)(buf + buf_size);
772 if (dp->d_ino == (ino_t)0)
774 namlen = dp->d_namlen;
775 if (namlen == length &&
776 strncmp(name, dp->d_name, length) == 0) {
778 *inumber_p = dp->d_ino;
782 dp = (struct ext2dirent *)((char *)dp + dp->d_reclen);
784 fp->f_seekp += buf_size;
790 ext2fs_close(struct open_file *f)
792 struct file *fp = (struct file *)f->f_fsdata;
795 f->f_fsdata = (void *)0;
796 if (fp == (struct file *)0)
799 for (level = 0; level < NIADDR; level++) {
800 if (fp->f_blk[level])
801 free(fp->f_blk[level]);
813 ext2fs_read(struct open_file *f, void *addr, size_t size, size_t *resid)
815 struct file *fp = (struct file *)f->f_fsdata;
816 size_t csize, buf_size;
821 if (fp->f_seekp >= fp->f_di.di_size)
824 error = buf_read_file(f, &buf, &buf_size);
829 if (csize > buf_size)
832 bcopy(buf, addr, csize);
834 fp->f_seekp += csize;
844 ext2fs_seek(struct open_file *f, off_t offset, int where)
846 struct file *fp = (struct file *)f->f_fsdata;
850 fp->f_seekp = offset;
853 fp->f_seekp += offset;
856 fp->f_seekp = fp->f_di.di_size - offset;
861 return (fp->f_seekp);
865 ext2fs_stat(struct open_file *f, struct stat *sb)
867 struct file *fp = (struct file *)f->f_fsdata;
869 /* only important stuff */
870 sb->st_mode = fp->f_di.di_mode;
871 sb->st_uid = fp->f_di.di_uid;
872 sb->st_gid = fp->f_di.di_gid;
873 sb->st_size = fp->f_di.di_size;
878 ext2fs_readdir(struct open_file *f, struct dirent *d)
880 struct file *fp = (struct file *)f->f_fsdata;
881 struct ext2dirent *ed;
887 * assume that a directory entry will not be split across blocks
890 if (fp->f_seekp >= fp->f_di.di_size)
892 error = buf_read_file(f, &buf, &buf_size);
895 ed = (struct ext2dirent *)buf;
896 fp->f_seekp += ed->d_reclen;
897 if (ed->d_ino == (ino_t)0)
899 d->d_type = EXTFTODT(ed->d_type);
900 strncpy(d->d_name, ed->d_name, ed->d_namlen);
901 d->d_name[ed->d_namlen] = '\0';