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authormsmith <msmith@FreeBSD.org>1998-08-20 08:19:55 +0000
committermsmith <msmith@FreeBSD.org>1998-08-20 08:19:55 +0000
commit335c4be5b17816baac6b70d4d0b3132925de858d (patch)
tree93349031c3cbd63fd287516f83a63841b7e8105b /lib/libstand/ufs.c
parent0ad6b3714378015da93827e12e95fa078a91ef12 (diff)
downloadFreeBSD-src-335c4be5b17816baac6b70d4d0b3132925de858d.zip
FreeBSD-src-335c4be5b17816baac6b70d4d0b3132925de858d.tar.gz
This is libstand; a support library for standalone executables (eg. bootstrap
modules). Obtained from: NetBSD, with some architectural changes and many additions.
Diffstat (limited to 'lib/libstand/ufs.c')
-rw-r--r--lib/libstand/ufs.c704
1 files changed, 704 insertions, 0 deletions
diff --git a/lib/libstand/ufs.c b/lib/libstand/ufs.c
new file mode 100644
index 0000000..2a2c56a
--- /dev/null
+++ b/lib/libstand/ufs.c
@@ -0,0 +1,704 @@
+/* $NetBSD: ufs.c,v 1.20 1998/03/01 07:15:39 ross 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.
+ */
+
+/*
+ * Stand-alone file reading package.
+ */
+
+#include <sys/param.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"
+
+static int ufs_open(char *path, struct open_file *f);
+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);
+
+struct fs_ops ufs_fsops = {
+ "ufs", ufs_open, ufs_close, ufs_read, null_write, ufs_seek, ufs_stat
+};
+
+
+/*
+ * In-core open file.
+ */
+struct file {
+ off_t f_seekp; /* seek pointer */
+ struct fs *f_fs; /* pointer to super-block */
+ struct dinode 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 */
+};
+
+static int read_inode(ino_t, struct open_file *);
+static int block_map(struct open_file *, daddr_t, daddr_t *);
+static int buf_read_file(struct open_file *, char **, size_t *);
+static int search_directory(char *, struct open_file *, ino_t *);
+#ifdef COMPAT_UFS
+static void ffs_oldfscompat(struct fs *);
+#endif
+
+/*
+ * Read a new inode into a file structure.
+ */
+static int
+read_inode(inumber, f)
+ ino_t inumber;
+ struct open_file *f;
+{
+ register struct file *fp = (struct file *)f->f_fsdata;
+ register struct fs *fs = fp->f_fs;
+ char *buf;
+ size_t rsize;
+ int rc;
+
+ /*
+ * 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;
+ }
+
+ {
+ register struct dinode *dp;
+
+ dp = (struct dinode *)buf;
+ fp->f_di = dp[ino_to_fsbo(fs, inumber)];
+ }
+
+ /*
+ * Clear out the old buffers
+ */
+ {
+ register int level;
+
+ for (level = 0; level < NIADDR; level++)
+ fp->f_blkno[level] = -1;
+ fp->f_buf_blkno = -1;
+ }
+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;
+ daddr_t file_block;
+ daddr_t *disk_block_p; /* out */
+{
+ register struct file *fp = (struct file *)f->f_fsdata;
+ register struct fs *fs = fp->f_fs;
+ int level;
+ int idx;
+ daddr_t ind_block_num;
+ daddr_t *ind_p;
+ 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 = 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();
+ 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;
+ }
+
+ 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(f, buf_p, size_p)
+ struct open_file *f;
+ char **buf_p; /* out */
+ size_t *size_p; /* out */
+{
+ register struct file *fp = (struct file *)f->f_fsdata;
+ register struct fs *fs = fp->f_fs;
+ long off;
+ register daddr_t file_block;
+ 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 = dblksize(fs, &fp->f_di, file_block);
+
+ if (file_block != fp->f_buf_blkno) {
+ rc = block_map(f, file_block, &disk_block);
+ if (rc)
+ return (rc);
+
+ 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();
+ 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 > fp->f_di.di_size - fp->f_seekp)
+ *size_p = fp->f_di.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 */
+{
+ register struct file *fp = (struct file *)f->f_fsdata;
+ register 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 < fp->f_di.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);
+}
+
+/*
+ * Open a file.
+ */
+static int
+ufs_open(path, f)
+ char *path;
+ struct open_file *f;
+{
+ register char *cp, *ncp;
+ register int c;
+ ino_t inumber, parent_inumber;
+ struct file *fp;
+ struct fs *fs;
+ int rc;
+ size_t buf_size;
+ int nlinks = 0;
+ char namebuf[MAXPATHLEN+1];
+ char *buf = 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(SBSIZE);
+ fp->f_fs = fs;
+ twiddle();
+ rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
+ SBLOCK, SBSIZE, (char *)fs, &buf_size);
+ if (rc)
+ goto out;
+
+ if (buf_size != SBSIZE || fs->fs_magic != FS_MAGIC ||
+ fs->fs_bsize > MAXBSIZE || fs->fs_bsize < sizeof(struct fs)) {
+ rc = EINVAL;
+ goto out;
+ }
+#ifdef COMPAT_UFS
+ ffs_oldfscompat(fs);
+#endif
+
+ /*
+ * Calculate indirect block levels.
+ */
+ {
+ register int mult;
+ register 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;
+ while (*cp) {
+
+ /*
+ * Remove extra separators
+ */
+ while (*cp == '/')
+ cp++;
+ if (*cp == '\0')
+ break;
+
+ /*
+ * Check that current node is a directory.
+ */
+ if ((fp->f_di.di_mode & IFMT) != IFDIR) {
+ rc = ENOTDIR;
+ goto out;
+ }
+
+ /*
+ * Get next component of path name.
+ */
+ {
+ register 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 ((fp->f_di.di_mode & IFMT) == IFLNK) {
+ int link_len = fp->f_di.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) {
+ bcopy(fp->f_di.di_shortlink, namebuf,
+ (unsigned) link_len);
+ } else {
+ /*
+ * Read file for symbolic link
+ */
+ size_t buf_size;
+ daddr_t disk_block;
+ register struct fs *fs = fp->f_fs;
+
+ if (!buf)
+ buf = malloc(fs->fs_bsize);
+ rc = block_map(f, (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;
+out:
+ if (buf)
+ free(buf);
+ 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;
+{
+ register 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 */
+{
+ register struct file *fp = (struct file *)f->f_fsdata;
+ register size_t csize;
+ char *buf;
+ size_t buf_size;
+ int rc = 0;
+ register char *addr = start;
+
+ while (size != 0) {
+ if (fp->f_seekp >= fp->f_di.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);
+}
+
+static off_t
+ufs_seek(f, offset, where)
+ struct open_file *f;
+ off_t offset;
+ int where;
+{
+ register 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
+ufs_stat(f, sb)
+ struct open_file *f;
+ struct stat *sb;
+{
+ register 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);
+}
+
+#ifdef COMPAT_UFS
+/*
+ * Sanity checks for old file systems.
+ *
+ * XXX - goes away some day.
+ */
+static void
+ffs_oldfscompat(fs)
+ struct fs *fs;
+{
+ int i;
+
+ fs->fs_npsect = max(fs->fs_npsect, fs->fs_nsect); /* XXX */
+ fs->fs_interleave = max(fs->fs_interleave, 1); /* XXX */
+ if (fs->fs_postblformat == FS_42POSTBLFMT) /* XXX */
+ fs->fs_nrpos = 8; /* XXX */
+ if (fs->fs_inodefmt < FS_44INODEFMT) { /* XXX */
+ quad_t sizepb = fs->fs_bsize; /* XXX */
+ /* XXX */
+ fs->fs_maxfilesize = fs->fs_bsize * NDADDR - 1; /* XXX */
+ for (i = 0; i < NIADDR; i++) { /* XXX */
+ sizepb *= NINDIR(fs); /* XXX */
+ fs->fs_maxfilesize += sizepb; /* XXX */
+ } /* XXX */
+ fs->fs_qbmask = ~fs->fs_bmask; /* XXX */
+ fs->fs_qfmask = ~fs->fs_fmask; /* XXX */
+ } /* XXX */
+}
+#endif
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