/* $OpenBSD: tables.h,v 1.2 1996/06/23 14:20:43 deraadt Exp $ */ /* $NetBSD: tables.h,v 1.3 1995/03/21 09:07:47 cgd Exp $ */ /*- * Copyright (c) 1992 Keith Muller. * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Keith Muller of the University of California, San Diego. * * 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. * * @(#)tables.h 8.1 (Berkeley) 5/31/93 */ /* * data structures and constants used by the different databases kept by pax */ /* * Hash Table Sizes MUST BE PRIME, if set too small performance suffers. * Probably safe to expect 500000 inodes per tape. Assuming good key * distribution (inodes) chains of under 50 long (worse case) is ok. */ #define L_TAB_SZ 2503 /* hard link hash table size */ #define F_TAB_SZ 50503 /* file time hash table size */ #define N_TAB_SZ 541 /* interactive rename hash table */ #define D_TAB_SZ 317 /* unique device mapping table */ #define A_TAB_SZ 317 /* ftree dir access time reset table */ #define MAXKEYLEN 64 /* max number of chars for hash */ /* * file hard link structure (hashed by dev/ino and chained) used to find the * hard links in a file system or with some archive formats (cpio) */ typedef struct hrdlnk { char *name; /* name of first file seen with this ino/dev */ dev_t dev; /* files device number */ ino_t ino; /* files inode number */ u_long nlink; /* expected link count */ struct hrdlnk *fow; } HRDLNK; /* * Archive write update file time table (the -u, -C flag), hashed by filename. * Filenames are stored in a scratch file at seek offset into the file. The * file time (mod time) and the file name length (for a quick check) are * stored in a hash table node. We were forced to use a scratch file because * with -u, the mtime for every node in the archive must always be available * to compare against (and this data can get REALLY large with big archives). * By being careful to read only when we have a good chance of a match, the * performance loss is not measurable (and the size of the archive we can * handle is greatly increased). */ typedef struct ftm { int namelen; /* file name length */ time_t mtime; /* files last modification time */ off_t seek; /* loacation in scratch file */ struct ftm *fow; } FTM; /* * Interactive rename table (-i flag), hashed by orig filename. * We assume this will not be a large table as this mapping data can only be * obtained through interactive input by the user. Nobody is going to type in * changes for 500000 files? We use chaining to resolve collisions. */ typedef struct namt { char *oname; /* old name */ char *nname; /* new name typed in by the user */ struct namt *fow; } NAMT; /* * Unique device mapping tables. Some protocols (e.g. cpio) require that the * <c_dev,c_ino> pair will uniquely identify a file in an archive unless they * are links to the same file. Appending to archives can break this. For those * protocols that have this requirement we map c_dev to a unique value not seen * in the archive when we append. We also try to handle inode truncation with * this table. (When the inode field in the archive header are too small, we * remap the dev on writes to remove accidental collisions). * * The list is hashed by device number using chain collision resolution. Off of * each DEVT are linked the various remaps for this device based on those bits * in the inode which were truncated. For example if we are just remapping to * avoid a device number during an update append, off the DEVT we would have * only a single DLIST that has a truncation id of 0 (no inode bits were * stripped for this device so far). When we spot inode truncation we create * a new mapping based on the set of bits in the inode which were stripped off. * so if the top four bits of the inode are stripped and they have a pattern of * 0110...... (where . are those bits not truncated) we would have a mapping * assigned for all inodes that has the same 0110.... pattern (with this dev * number of course). This keeps the mapping sparse and should be able to store * close to the limit of files which can be represented by the optimal * combination of dev and inode bits, and without creating a fouled up archive. * Note we also remap truncated devs in the same way (an exercise for the * dedicated reader; always wanted to say that...:) */ typedef struct devt { dev_t dev; /* the orig device number we now have to map */ struct devt *fow; /* new device map list */ struct dlist *list; /* map list based on inode truncation bits */ } DEVT; typedef struct dlist { ino_t trunc_bits; /* truncation pattern for a specific map */ dev_t dev; /* the new device id we use */ struct dlist *fow; } DLIST; /* * ftree directory access time reset table. When we are done with with a * subtree we reset the access and mod time of the directory when the tflag is * set. Not really explicitly specified in the pax spec, but easy and fast to * do (and this may have even been intended in the spec, it is not clear). * table is hashed by inode with chaining. */ typedef struct atdir { char *name; /* name of directory to reset */ dev_t dev; /* dev and inode for fast lookup */ ino_t ino; time_t mtime; /* access and mod time to reset to */ time_t atime; struct atdir *fow; } ATDIR; /* * created directory time and mode storage entry. After pax is finished during * extraction or copy, we must reset directory access modes and times that * may have been modified after creation (they no longer have the specified * times and/or modes). We must reset time in the reverse order of creation, * because entries are added from the top of the file tree to the bottom. * We MUST reset times from leaf to root (it will not work the other * direction). Entries are recorded into a spool file to make reverse * reading faster. */ typedef struct dirdata { int nlen; /* length of the directory name (includes \0) */ off_t npos; /* position in file where this dir name starts */ mode_t mode; /* file mode to restore */ time_t mtime; /* mtime to set */ time_t atime; /* atime to set */ int frc_mode; /* do we force mode settings? */ } DIRDATA;