fsys_ffs.rar_grub

/* * GRUB -- GRand Unified Bootloader * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* * Elements of this file were originally from the FreeBSD "biosboot" * bootloader file "disk.c" dated 4/12/95. * * The license and header comments from that file are included here. */ /* * Mach Operating System * Copyright (c) 1992, 1991 Carnegie Mellon University * All Rights Reserved. * * 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 Mellon * the rights to redistribute these changes. * * from: Mach, Revision 2.2 92/04/04 11:35:49 rpd * $Id: fsys_ffs.c,v 1.10 2001/11/12 06:57:29 okuji Exp $ */ #ifdef FSYS_FFS #include "shared.h" #include "filesys.h" #include "defs.h" #include "disk_inode.h" #include "disk_inode_ffs.h" #include "dir.h" #include "fs.h" /* used for filesystem map blocks */ static int mapblock; static int mapblock_offset; static int mapblock_bsize; /* pointer to superblock */ #define SUPERBLOCK ((struct fs *) ( FSYS_BUF + 8192 )) #define INODE ((struct icommon *) ( FSYS_BUF + 16384 )) #define MAPBUF ( FSYS_BUF + 24576 ) #define MAPBUF_LEN 8192 int ffs_mount (void) { int retval = 1; if ((((current_drive & 0x80) || (current_slice != 0)) && ! IS_PC_SLICE_TYPE_BSD_WITH_FS (current_slice, FS_BSDFFS)) || part_length < (SBLOCK + (SBSIZE / DEV_BSIZE)) || !devread (SBLOCK, 0, SBSIZE, (char *) SUPERBLOCK) || SUPERBLOCK->fs_magic != FS_MAGIC) retval = 0; mapblock = -1; mapblock_offset = -1; return retval; } static int block_map (int file_block) { int bnum, offset, bsize; if (file_block < NDADDR) return (INODE->i_db[file_block]); /* If the blockmap loaded does not include FILE_BLOCK, load a new blockmap. */ if ((bnum = fsbtodb (SUPERBLOCK, INODE->i_ib[0])) != mapblock || (mapblock_offset <= bnum && bnum <= mapblock_offset + mapblock_bsize)) { if (MAPBUF_LEN < SUPERBLOCK->fs_bsize) { offset = ((file_block - NDADDR) % NINDIR (SUPERBLOCK)); bsize = MAPBUF_LEN; if (offset + MAPBUF_LEN > SUPERBLOCK->fs_bsize) offset = (SUPERBLOCK->fs_bsize - MAPBUF_LEN) / sizeof (int); } else { bsize = SUPERBLOCK->fs_bsize; offset = 0; } if (! devread (bnum, offset * sizeof (int), bsize, (char *) MAPBUF)) { mapblock = -1; mapblock_bsize = -1; mapblock_offset = -1; errnum = ERR_FSYS_CORRUPT; return -1; } mapblock = bnum; mapblock_bsize = bsize; mapblock_offset = offset; } return (((int *) MAPBUF)[((file_block - NDADDR) % NINDIR (SUPERBLOCK)) - mapblock_offset]); } int ffs_read (char *buf, int len) { int logno, off, size, map, ret = 0; while (len && !errnum) { off = blkoff (SUPERBLOCK, filepos); logno = lblkno (SUPERBLOCK, filepos); size = blksize (SUPERBLOCK, INODE, logno); if ((map = block_map (logno)) < 0) break; size -= off; if (size > len) size = len; disk_read_func = disk_read_hook; devread (fsbtodb (SUPERBLOCK, map), off, size, buf); disk_read_func = NULL; buf += size; len -= size; filepos += size; ret += size; } if (errnum) ret = 0; return ret; } int ffs_dir (char *dirname) { char *rest, ch; int block, off, loc, map, ino = ROOTINO; struct direct *dp; /* main loop to find destination inode */ loop: /* load current inode (defaults to the root inode) */ if (!devread (fsbtodb (SUPERBLOCK, itod (SUPERBLOCK, ino)), ino % (SUPERBLOCK->fs_inopb) * sizeof (struct dinode), sizeof (struct dinode), (char *) INODE)) return 0; /* XXX what return value? */ /* if we have a real file (and we're not just printing possibilities), then this is where we want to exit */ if (!*dirname || isspace (*dirname)) { if ((INODE->i_mode & IFMT) != IFREG) { errnum = ERR_BAD_FILETYPE; return 0; } filemax = INODE->i_size; /* incomplete implementation requires this! */ fsmax = (NDADDR + NINDIR (SUPERBLOCK)) * SUPERBLOCK->fs_bsize; return 1; } /* continue with file/directory name interpretation */ while (*dirname == '/') dirname++; if (!(INODE->i_size) || ((INODE->i_mode & IFMT) != IFDIR)) { errnum = ERR_BAD_FILETYPE; return 0; } for (rest = dirname; (ch = *rest) && !isspace (ch) && ch != '/'; rest++); *rest = 0; loc = 0; /* loop for reading a the entries in a directory */ do { if (loc >= INODE->i_size) { #if 0 putchar ('\n'); #endif if (print_possibilities < 0) return 1; errnum = ERR_FILE_NOT_FOUND; *rest = ch; return 0; } if (!(off = blkoff (SUPERBLOCK, loc))) { block = lblkno (SUPERBLOCK, loc); if ((map = block_map (block)) < 0 || !devread (fsbtodb (SUPERBLOCK, map), 0, blksize (SUPERBLOCK, INODE, block), (char *) FSYS_BUF)) { errnum = ERR_FSYS_CORRUPT; *rest = ch; return 0; } } dp = (struct direct *) (FSYS_BUF + off); loc += dp->d_reclen; #ifndef STAGE1_5 if (dp->d_ino && print_possibilities && ch != '/' && (!*dirname || substring (dirname, dp->d_name) <= 0)) { if (print_possibilities > 0) print_possibilities = -print_possibilities; print_a_completion (dp->d_name); } #endif /* STAGE1_5 */ } while (!dp->d_ino || (substring (dirname, dp->d_name) != 0 || (print_possibilities && ch != '/'))); /* only get here if we have a matching directory entry */ ino = dp->d_ino; *(dirname = rest) = ch; /* go back to main loop at top of function */ goto loop; } int ffs_embed (int *start_sector, int needed_sectors) { /* XXX: I don't know if this is really correct. Someone who is familiar with BSD should check for this. */ if (needed_sectors > 14) return 0; *start_sector = 1; #if 1 /* FIXME: Disable the embedding in FFS until someone checks if the code above is correct. */ return 0; #else return 1; #endif } #endif /* FSYS_FFS */