/*- * Copyright (c) 1999,2000 Jonathan Lemon * All rights reserved. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. * * $FreeBSD: src/lib/libstand/ext2fs.c,v 1.1.2.2 2001/03/05 06:26:07 kris Exp $ * $DragonFly: src/lib/libstand/ext2fs.c,v 1.2 2003/06/17 04:26:51 dillon Exp $ */ /*- * Copyright (c) 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 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 #include #include "stand.h" #include "string.h" static int ext2fs_open(const char *path, struct open_file *f); static int ext2fs_close(struct open_file *f); static int ext2fs_read(struct open_file *f, void *buf, size_t size, size_t *resid); static off_t ext2fs_seek(struct open_file *f, off_t offset, int where); static int ext2fs_stat(struct open_file *f, struct stat *sb); static int ext2fs_readdir(struct open_file *f, struct dirent *d); static int dtmap[] = { DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK }; #define EXTFTODT(x) (x) > sizeof(dtmap) / sizeof(dtmap[0]) ? \ DT_UNKNOWN : dtmap[x] struct fs_ops ext2fs_fsops = { "ext2fs", ext2fs_open, ext2fs_close, ext2fs_read, null_write, ext2fs_seek, ext2fs_stat, ext2fs_readdir }; #define EXT2_SBSIZE 1024 #define EXT2_SBLOCK (1024 / DEV_BSIZE) /* block offset of superblock */ #define EXT2_MAGIC 0xef53 #define EXT2_ROOTINO 2 #define EXT2_REV0 0 /* original revision of ext2 */ #define EXT2_R0_ISIZE 128 /* inode size */ #define EXT2_R0_FIRSTINO 11 /* first inode */ #define EXT2_MINBSHIFT 10 /* mininum block shift */ #define EXT2_MINFSHIFT 10 /* mininum frag shift */ #define NDADDR 12 /* # of direct blocks */ #define NIADDR 3 /* # of indirect blocks */ /* * file system block to disk address */ #define fsb_to_db(fs, blk) ((blk) << (fs)->fs_fsbtodb) /* * inode to block group offset * inode to block group * inode to disk address * inode to block offset */ #define ino_to_bgo(fs, ino) (((ino) - 1) % (fs)->fs_ipg) #define ino_to_bg(fs, ino) (((ino) - 1) / (fs)->fs_ipg) #define ino_to_db(fs, bg, ino) \ fsb_to_db(fs, ((bg)[ino_to_bg(fs, ino)].bg_inotbl + \ ino_to_bgo(fs, ino) / (fs)->fs_ipb)) #define ino_to_bo(fs, ino) (ino_to_bgo(fs, ino) % (fs)->fs_ipb) #define nindir(fs) \ ((fs)->fs_bsize / sizeof(u_int32_t)) #define lblkno(fs, loc) /* loc / bsize */ \ ((loc) >> (fs)->fs_bshift) #define smalllblktosize(fs, blk) /* blk * bsize */ \ ((blk) << (fs)->fs_bshift) #define blkoff(fs, loc) /* loc % bsize */ \ ((loc) & (fs)->fs_bmask) #define fragroundup(fs, size) /* roundup(size, fsize) */ \ (((size) + (fs)->fs_fmask) & ~(fs)->fs_fmask) #define dblksize(fs, dip, lbn) \ (((lbn) >= NDADDR || (dip)->di_size >= smalllblktosize(fs, (lbn) + 1)) \ ? (fs)->fs_bsize \ : (fragroundup(fs, blkoff(fs, (dip)->di_size)))) /* * superblock describing ext2fs */ struct ext2fs_disk { u_int32_t fd_inodes; /* # of inodes */ u_int32_t fd_blocks; /* # of blocks */ u_int32_t fd_resblk; /* # of reserved blocks */ u_int32_t fd_freeblk; /* # of free blocks */ u_int32_t fd_freeino; /* # of free inodes */ u_int32_t fd_firstblk; /* first data block */ u_int32_t fd_bsize; /* block size */ u_int32_t fd_fsize; /* frag size */ u_int32_t fd_bpg; /* blocks per group */ u_int32_t fd_fpg; /* frags per group */ u_int32_t fd_ipg; /* inodes per group */ u_int32_t fd_mtime; /* mount time */ u_int32_t fd_wtime; /* write time */ u_int16_t fd_mount; /* # of mounts */ int16_t fd_maxmount; /* max # of mounts */ u_int16_t fd_magic; /* magic number */ u_int16_t fd_state; /* state */ u_int16_t fd_eflag; /* error flags */ u_int16_t fd_mnrrev; /* minor revision */ u_int32_t fd_lastchk; /* last check */ u_int32_t fd_chkintvl; /* maximum check interval */ u_int32_t fd_os; /* os */ u_int32_t fd_revision; /* revision */ u_int16_t fd_uid; /* uid for reserved blocks */ u_int16_t fd_gid; /* gid for reserved blocks */ u_int32_t fd_firstino; /* first non-reserved inode */ u_int16_t fd_isize; /* inode size */ u_int16_t fd_nblkgrp; /* block group # of superblock */ u_int32_t fd_fcompat; /* compatible features */ u_int32_t fd_fincompat; /* incompatible features */ u_int32_t fd_frocompat; /* read-only compatibilties */ u_int8_t fd_uuid[16]; /* volume uuid */ char fd_volname[16]; /* volume name */ char fd_fsmnt[64]; /* name last mounted on */ u_int32_t fd_bitmap; /* compression bitmap */ u_int8_t fd_nblkpa; /* # of blocks to preallocate */ u_int8_t fd_ndblkpa; /* # of dir blocks to preallocate */ }; struct ext2fs_core { int fc_bsize; /* block size */ int fc_bshift; /* block shift amount */ int fc_bmask; /* block mask */ int fc_fsize; /* frag size */ int fc_fshift; /* frag shift amount */ int fc_fmask; /* frag mask */ int fc_isize; /* inode size */ int fc_imask; /* inode mask */ int fc_firstino; /* first non-reserved inode */ int fc_ipb; /* inodes per block */ int fc_fsbtodb; /* fsb to ds shift */ }; struct ext2fs { struct ext2fs_disk fs_fd; char fs_pad[EXT2_SBSIZE - sizeof(struct ext2fs_disk)]; struct ext2fs_core fs_fc; #define fs_magic fs_fd.fd_magic #define fs_revision fs_fd.fd_revision #define fs_blocks fs_fd.fd_blocks #define fs_firstblk fs_fd.fd_firstblk #define fs_bpg fs_fd.fd_bpg #define fs_ipg fs_fd.fd_ipg #define fs_bsize fs_fc.fc_bsize #define fs_bshift fs_fc.fc_bshift #define fs_bmask fs_fc.fc_bmask #define fs_fsize fs_fc.fc_fsize #define fs_fshift fs_fc.fc_fshift #define fs_fmask fs_fc.fc_fmask #define fs_isize fs_fc.fc_isize #define fs_imask fs_fc.fc_imask #define fs_firstino fs_fc.fc_firstino #define fs_ipb fs_fc.fc_ipb #define fs_fsbtodb fs_fc.fc_fsbtodb }; struct ext2blkgrp { u_int32_t bg_blkmap; /* block bitmap */ u_int32_t bg_inomap; /* inode bitmap */ u_int32_t bg_inotbl; /* inode table */ u_int16_t bg_nfblk; /* # of free blocks */ u_int16_t bg_nfino; /* # of free inodes */ u_int16_t bg_ndirs; /* # of dirs */ char bg_pad[14]; }; struct ext2dinode { u_int16_t di_mode; /* mode */ u_int16_t di_uid; /* uid */ u_int32_t di_size; /* byte size */ u_int32_t di_atime; /* access time */ u_int32_t di_ctime; /* creation time */ u_int32_t di_mtime; /* modification time */ u_int32_t di_dtime; /* deletion time */ u_int16_t di_gid; /* gid */ u_int16_t di_nlink; /* link count */ u_int32_t di_nblk; /* block count */ u_int32_t di_flags; /* file flags */ u_int32_t di_osdep1; /* os dependent stuff */ u_int32_t di_db[NDADDR]; /* direct blocks */ u_int32_t di_ib[NIADDR]; /* indirect blocks */ u_int32_t di_version; /* version */ u_int32_t di_facl; /* file acl */ u_int32_t di_dacl; /* dir acl */ u_int32_t di_faddr; /* fragment addr */ u_int8_t di_frag; /* fragment number */ u_int8_t di_fsize; /* fragment size */ char di_pad[10]; #define di_shortlink di_db }; #define EXT2_MAXNAMLEN 255 struct ext2dirent { u_int32_t d_ino; /* inode */ u_int16_t d_reclen; /* directory entry length */ u_int8_t d_namlen; /* name length */ u_int8_t d_type; /* file type */ char d_name[EXT2_MAXNAMLEN]; }; struct file { off_t f_seekp; /* seek pointer */ struct ext2fs *f_fs; /* pointer to super-block */ struct ext2blkgrp *f_bg; /* pointer to blkgrp map */ struct ext2dinode 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 */ daddr_t f_blkno[NIADDR]; /* disk address of block in buffer */ char *f_buf; /* buffer for data block */ size_t f_buf_size; /* size of data block */ daddr_t f_buf_blkno; /* block number of data block */ }; /* forward decls */ static int read_inode(ino_t inumber, struct open_file *f); static int block_map(struct open_file *f, daddr_t file_block, daddr_t *disk_block_p); static int buf_read_file(struct open_file *f, char **buf_p, size_t *size_p); static int search_directory(char *name, struct open_file *f, ino_t *inumber_p); /* * Open a file. */ static int ext2fs_open(const char *upath, struct open_file *f) { struct file *fp; struct ext2fs *fs; size_t buf_size; ino_t inumber, parent_inumber; int i, len, groups, bg_per_blk, blkgrps, mult; int nlinks = 0; int error = 0; char *cp, *ncp, *path = NULL, *buf = NULL; char namebuf[MAXPATHLEN+1]; char c; /* allocate file system specific data structure */ fp = malloc(sizeof(struct file)); if (fp == NULL) return (ENOMEM); bzero(fp, sizeof(struct file)); f->f_fsdata = (void *)fp; /* allocate space and read super block */ fs = (struct ext2fs *)malloc(sizeof(*fs)); fp->f_fs = fs; twiddle(); error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ, EXT2_SBLOCK, EXT2_SBSIZE, (char *)fs, &buf_size); if (error) goto out; if (buf_size != EXT2_SBSIZE || fs->fs_magic != EXT2_MAGIC) { error = EINVAL; goto out; } /* * compute in-core values for the superblock */ fs->fs_bshift = EXT2_MINBSHIFT + fs->fs_fd.fd_bsize; fs->fs_bsize = 1 << fs->fs_bshift; fs->fs_bmask = fs->fs_bsize - 1; fs->fs_fshift = EXT2_MINFSHIFT + fs->fs_fd.fd_fsize; fs->fs_fsize = 1 << fs->fs_fshift; fs->fs_fmask = fs->fs_fsize - 1; if (fs->fs_revision == EXT2_REV0) { fs->fs_isize = EXT2_R0_ISIZE; fs->fs_firstino = EXT2_R0_FIRSTINO; } else { fs->fs_isize = fs->fs_fd.fd_isize; fs->fs_firstino = fs->fs_fd.fd_firstino; } fs->fs_imask = fs->fs_isize - 1; fs->fs_ipb = fs->fs_bsize / fs->fs_isize; fs->fs_fsbtodb = (fs->fs_bsize / DEV_BSIZE) - 1; /* * we have to load in the "group descriptors" here */ groups = howmany(fs->fs_blocks - fs->fs_firstblk, fs->fs_bpg); bg_per_blk = fs->fs_bsize / sizeof(struct ext2blkgrp); blkgrps = howmany(groups, bg_per_blk); len = blkgrps * fs->fs_bsize; fp->f_bg = malloc(len); twiddle(); error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ, EXT2_SBLOCK + EXT2_SBSIZE / DEV_BSIZE, len, (char *)fp->f_bg, &buf_size); if (error) goto out; /* * XXX * validation of values? (blocksize, descriptors, etc?) */ /* * Calculate indirect block levels. */ mult = 1; for (i = 0; i < NIADDR; i++) { mult *= nindir(fs); fp->f_nindir[i] = mult; } inumber = EXT2_ROOTINO; if ((error = read_inode(inumber, f)) != 0) goto out; path = strdup(upath); if (path == NULL) { error = ENOMEM; goto out; } cp = path; while (*cp) { /* * Remove extra separators */ while (*cp == '/') cp++; if (*cp == '\0') break; /* * Check that current node is a directory. */ if (! S_ISDIR(fp->f_di.di_mode)) { error = ENOTDIR; goto out; } /* * Get next component of path name. */ len = 0; ncp = cp; while ((c = *cp) != '\0' && c != '/') { if (++len > EXT2_MAXNAMLEN) { error = 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; error = search_directory(ncp, f, &inumber); *cp = c; if (error) goto out; /* * Open next component. */ if ((error = read_inode(inumber, f)) != 0) goto out; /* * Check for symbolic link. */ if (S_ISLNK(fp->f_di.di_mode)) { int link_len = fp->f_di.di_size; int len; len = strlen(cp); if (link_len + len > MAXPATHLEN || ++nlinks > MAXSYMLINKS) { error = ENOENT; goto out; } bcopy(cp, &namebuf[link_len], len + 1); if (fp->f_di.di_nblk == 0) { bcopy(fp->f_di.di_shortlink, namebuf, link_len); } else { /* * Read file for symbolic link */ struct ext2fs *fs = fp->f_fs; daddr_t disk_block; size_t buf_size; if (! buf) buf = malloc(fs->fs_bsize); error = block_map(f, (daddr_t)0, &disk_block); if (error) goto out; twiddle(); error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ, fsb_to_db(fs, disk_block), fs->fs_bsize, buf, &buf_size); if (error) goto out; bcopy((char *)buf, namebuf, 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)EXT2_ROOTINO; if ((error = read_inode(inumber, f)) != 0) goto out; } } /* * Found terminal component. */ error = 0; out: if (buf) free(buf); if (path) free(path); if (error) { if (fp->f_buf) free(fp->f_buf); free(fp->f_fs); free(fp); } return (error); } /* * Read a new inode into a file structure. */ static int read_inode(ino_t inumber, struct open_file *f) { struct file *fp = (struct file *)f->f_fsdata; struct ext2fs *fs = fp->f_fs; struct ext2dinode *dp; char *buf; size_t rsize; int level, error = 0; /* * Read inode and save it. */ buf = malloc(fs->fs_bsize); twiddle(); error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ, ino_to_db(fs, fp->f_bg, inumber), fs->fs_bsize, buf, &rsize); if (error) goto out; if (rsize != fs->fs_bsize) { error = EIO; goto out; } dp = (struct ext2dinode *)buf; fp->f_di = dp[ino_to_bo(fs, inumber)]; /* clear out old buffers */ for (level = 0; level < NIADDR; level++) fp->f_blkno[level] = -1; fp->f_buf_blkno = -1; out: free(buf); return (error); } /* * Given an offset in a file, find the disk block number that * contains that block. */ static int block_map(struct open_file *f, daddr_t file_block, daddr_t *disk_block_p) { struct file *fp = (struct file *)f->f_fsdata; struct ext2fs *fs = fp->f_fs; daddr_t ind_block_num; daddr_t *ind_p; int idx, level; int error; /* * 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 = fp->f_di.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 = fp->f_di.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(); error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ, fsb_to_db(fp->f_fs, ind_block_num), fs->fs_bsize, fp->f_blk[level], &fp->f_blksize[level]); if (error) return (error); if (fp->f_blksize[level] != fs->fs_bsize) return (EIO); fp->f_blkno[level] = ind_block_num; } ind_p = (daddr_t *)fp->f_blk[level]; if (level > 0) { idx = file_block / fp->f_nindir[level - 1]; file_block %= fp->f_nindir[level - 1]; } else { idx = file_block; } ind_block_num = ind_p[idx]; } *disk_block_p = ind_block_num; return (0); } /* * 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(struct open_file *f, char **buf_p, size_t *size_p) { struct file *fp = (struct file *)f->f_fsdata; struct ext2fs *fs = fp->f_fs; long off; daddr_t file_block; daddr_t disk_block; size_t block_size; int error = 0; off = blkoff(fs, fp->f_seekp); file_block = lblkno(fs, fp->f_seekp); block_size = dblksize(fs, &fp->f_di, file_block); if (file_block != fp->f_buf_blkno) { error = block_map(f, file_block, &disk_block); if (error) goto done; if (fp->f_buf == (char *)0) fp->f_buf = malloc(fs->fs_bsize); if (disk_block == 0) { bzero(fp->f_buf, block_size); fp->f_buf_size = block_size; } else { twiddle(); error = (f->f_dev->dv_strategy)(f->f_devdata, F_READ, fsb_to_db(fs, disk_block), block_size, fp->f_buf, &fp->f_buf_size); if (error) goto done; } 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 > fp->f_di.di_size - fp->f_seekp) *size_p = fp->f_di.di_size - fp->f_seekp; done: return (error); } /* * Search a directory for a name and return its * i_number. */ static int search_directory(char *name, struct open_file *f, ino_t *inumber_p) { struct file *fp = (struct file *)f->f_fsdata; struct ext2dirent *dp, *edp; char *buf; size_t buf_size; int namlen, length; int error; length = strlen(name); fp->f_seekp = 0; while (fp->f_seekp < fp->f_di.di_size) { error = buf_read_file(f, &buf, &buf_size); if (error) return (error); dp = (struct ext2dirent *)buf; edp = (struct ext2dirent *)(buf + buf_size); while (dp < edp) { if (dp->d_ino == (ino_t)0) goto next; namlen = dp->d_namlen; if (namlen == length && strncmp(name, dp->d_name, length) == 0) { /* found entry */ *inumber_p = dp->d_ino; return (0); } next: dp = (struct ext2dirent *)((char *)dp + dp->d_reclen); } fp->f_seekp += buf_size; } return (ENOENT); } static int ext2fs_close(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); if (fp->f_bg) free(fp->f_bg); free(fp->f_fs); free(fp); return (0); } static int ext2fs_read(struct open_file *f, void *addr, size_t size, size_t *resid) { struct file *fp = (struct file *)f->f_fsdata; size_t csize, buf_size; char *buf; int error = 0; while (size != 0) { if (fp->f_seekp >= fp->f_di.di_size) break; error = buf_read_file(f, &buf, &buf_size); if (error) 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 (error); } static off_t ext2fs_seek(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 = fp->f_di.di_size - offset; break; default: return (-1); } return (fp->f_seekp); } static int ext2fs_stat(struct open_file *f, struct stat *sb) { struct file *fp = (struct file *)f->f_fsdata; /* only important stuff */ sb->st_mode = fp->f_di.di_mode; sb->st_uid = fp->f_di.di_uid; sb->st_gid = fp->f_di.di_gid; sb->st_size = fp->f_di.di_size; return (0); } static int ext2fs_readdir(struct open_file *f, struct dirent *d) { struct file *fp = (struct file *)f->f_fsdata; struct ext2dirent *ed; char *buf; size_t buf_size; int error; /* * assume that a directory entry will not be split across blocks */ again: if (fp->f_seekp >= fp->f_di.di_size) return (ENOENT); error = buf_read_file(f, &buf, &buf_size); if (error) return (error); ed = (struct ext2dirent *)buf; fp->f_seekp += ed->d_reclen; if (ed->d_ino == (ino_t)0) goto again; d->d_type = EXTFTODT(ed->d_type); strncpy(d->d_name, ed->d_name, ed->d_namlen); d->d_name[ed->d_namlen] = '\0'; return (0); }