2 * Ported to Linux's Second Extended File System as part of the
3 * dump and restore backup suit
4 * Remy Card <card@Linux.EU.Org>, 1994-1997
5 * Stelian Pop <stelian@popies.net>, 1999-2000
6 * Stelian Pop <stelian@popies.net> - AlcĂ´ve <www.alcove.com>, 2000-2002
10 * Copyright (c) 1983, 1993
11 * The Regents of the University of California. All rights reserved.
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 static const char rcsid[] =
40 "$Id: symtab.c,v 1.22 2003/10/26 16:05:48 stelian Exp $";
44 * These routines maintain the symbol table which tracks the state
45 * of the file system being restored. They provide lookup by either
46 * name or inode number. They also provide for creation, deletion,
47 * and renaming of entries. Because of the dynamic nature of pathnames,
48 * names should not be saved, but always constructed just before they
49 * are needed, by calling "myname".
53 #include <sys/param.h>
59 #ifdef HAVE_EXT2FS_EXT2_FS_H
60 #include <ext2fs/ext2_fs.h>
62 #include <linux/ext2_fs.h>
64 #include <bsdcompat.h>
67 #include <sys/fcntl.h>
68 #include <bsdcompat.h>
70 #include <ufs/ufs/dinode.h>
72 #endif /* __linux__ */
75 #include <compaterr.h>
83 #include <ext2fs/ext2fs.h>
90 * The following variables define the inode symbol table.
91 * The primary hash table is dynamically allocated based on
92 * the number of inodes in the file system (maxino), scaled by
93 * HASHFACTOR. The variable "entry" points to the hash table;
94 * the variable "entrytblsize" indicates its size (in entries).
97 static struct entry **entry;
98 static long entrytblsize;
100 static void addino __P((dump_ino_t, struct entry *));
101 static struct entry *lookupparent __P((char *));
102 static void removeentry __P((struct entry *));
105 * Look up an entry by inode number
108 lookupino(dump_ino_t inum)
112 if (inum < WINO || inum >= maxino)
114 for (ep = entry[inum % entrytblsize]; ep != NULL; ep = ep->e_next)
115 if (ep->e_ino == inum)
121 * Add an entry into the entry table
124 addino(dump_ino_t inum, struct entry *np)
128 if (inum < WINO || inum >= maxino)
129 panic("addino: out of range %d\n", inum);
130 epp = &entry[inum % entrytblsize];
135 for (np = np->e_next; np != NULL; np = np->e_next)
136 if (np->e_ino == inum)
137 badentry(np, "duplicate inum");
141 * Delete an entry from the entry table
144 deleteino(dump_ino_t inum)
149 if (inum < WINO || inum >= maxino)
150 panic("deleteino: out of range %d\n", inum);
151 prev = &entry[inum % entrytblsize];
152 for (next = *prev; next != NULL; next = next->e_next) {
153 if (next->e_ino == inum) {
155 *prev = next->e_next;
158 prev = &next->e_next;
160 panic("deleteino: %d not found\n", inum);
164 * Look up an entry by name
167 lookupname(char *name)
171 char buf[MAXPATHLEN];
174 for (ep = lookupino(ROOTINO); ep != NULL; ep = ep->e_entries) {
175 for (np = buf; *cp != '/' && *cp != '\0' &&
176 np < &buf[sizeof(buf)]; )
178 if (np == &buf[sizeof(buf)])
181 for ( ; ep != NULL; ep = ep->e_sibling)
182 if (strcmp(ep->e_name, buf) == 0)
193 * Look up the parent of a pathname
195 static struct entry *
196 lookupparent(char *name)
201 tailindex = strrchr(name, '/');
202 if (tailindex == NULL)
205 ep = lookupname(name);
209 if (ep->e_type != NODE)
210 panic("%s is not a directory\n", name);
215 * Determine the current pathname of a node or leaf
218 myname(struct entry *ep)
221 static char namebuf[MAXPATHLEN];
223 for (cp = &namebuf[MAXPATHLEN - 2]; cp > &namebuf[ep->e_namlen]; ) {
225 memmove(cp, ep->e_name, (size_t)ep->e_namlen);
226 if (ep == lookupino(ROOTINO))
231 panic("%s: pathname too long\n", cp);
236 * Unused symbol table entries are linked together on a free list
237 * headed by the following pointer.
239 static struct entry *freelist = NULL;
242 * add an entry to the symbol table
245 addentry(char *name, dump_ino_t inum, int type)
247 struct entry *np, *ep;
249 if (freelist != NULL) {
251 freelist = np->e_next;
252 memset(np, 0, sizeof(struct entry));
254 np = (struct entry *)calloc(1, sizeof(struct entry));
256 errx(1, "no memory to extend symbol table");
258 np->e_type = type & ~LINK;
259 ep = lookupparent(name);
261 if (inum != ROOTINO || lookupino(ROOTINO) != NULL)
262 panic("bad name to addentry %s\n", name);
263 np->e_name = savename(name);
264 np->e_namlen = strlen(name);
269 np->e_name = savename(strrchr(name, '/') + 1);
270 np->e_namlen = strlen(np->e_name);
272 np->e_sibling = ep->e_entries;
275 ep = lookupino(inum);
277 panic("link to non-existent name\n");
279 np->e_links = ep->e_links;
281 } else if (inum != 0) {
282 if (lookupino(inum) != NULL)
283 panic("duplicate entry\n");
290 * delete an entry from the symbol table
293 freeentry(struct entry *ep)
298 if (ep->e_flags != REMOVED)
299 badentry(ep, "not marked REMOVED");
300 if (ep->e_type == NODE) {
301 if (ep->e_links != NULL)
302 badentry(ep, "freeing referenced directory");
303 if (ep->e_entries != NULL)
304 badentry(ep, "freeing non-empty directory");
306 if (ep->e_ino != 0) {
307 np = lookupino(ep->e_ino);
309 badentry(ep, "lookupino failed");
313 if (ep->e_links != NULL)
314 addino(inum, ep->e_links);
316 for (; np != NULL; np = np->e_links) {
317 if (np->e_links == ep) {
318 np->e_links = ep->e_links;
323 badentry(ep, "link not found");
327 freename(ep->e_name);
328 ep->e_next = freelist;
333 * Relocate an entry in the tree structure
336 moveentry(struct entry *ep, char *newname)
341 np = lookupparent(newname);
343 badentry(ep, "cannot move ROOT");
344 if (np != ep->e_parent) {
347 ep->e_sibling = np->e_entries;
350 cp = strrchr(newname, '/') + 1;
351 freename(ep->e_name);
352 ep->e_name = savename(cp);
353 ep->e_namlen = strlen(cp);
354 if (strcmp(gentempname(ep), ep->e_name) == 0)
355 ep->e_flags |= TMPNAME;
357 ep->e_flags &= ~TMPNAME;
361 * Remove an entry in the tree structure
364 removeentry(struct entry *ep)
369 if (np->e_entries == ep) {
370 np->e_entries = ep->e_sibling;
372 for (np = np->e_entries; np != NULL; np = np->e_sibling) {
373 if (np->e_sibling == ep) {
374 np->e_sibling = ep->e_sibling;
379 badentry(ep, "cannot find entry in parent list");
384 * Table of unused string entries, sorted by length.
386 * Entries are allocated in STRTBLINCR sized pieces so that names
387 * of similar lengths can use the same entry. The value of STRTBLINCR
388 * is chosen so that every entry has at least enough space to hold
389 * a "struct strtbl" header. Thus every entry can be linked onto an
390 * appropriate free list.
392 * NB. The macro "allocsize" below assumes that "struct strhdr"
393 * has a size that is a power of two.
399 #define STRTBLINCR (sizeof(struct strhdr))
400 #define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1))
402 static struct strhdr strtblhdr[allocsize(MAXNAMLEN) / STRTBLINCR];
405 * Allocate space for a name. It first looks to see if it already
406 * has an appropriate sized entry, and if not allocates a new one.
418 np = strtblhdr[len / STRTBLINCR].next;
420 strtblhdr[len / STRTBLINCR].next = np->next;
423 cp = malloc((unsigned)allocsize(len));
425 errx(1, "no space for string table");
427 (void) strcpy(cp, name);
432 * Free space for a name. The resulting entry is linked onto the
433 * appropriate free list.
438 struct strhdr *tp, *np;
440 tp = &strtblhdr[strlen(name) / STRTBLINCR];
441 np = (struct strhdr *)name;
447 * Useful quantities placed at the end of a dumped symbol table.
449 struct symtableheader {
452 int32_t entrytblsize;
461 * dump a snapshot of the symbol table
464 dumpsymtable(char *filename, long checkpt)
466 struct entry *ep, *tep;
468 struct entry temp, *tentry;
469 long mynum = 1, stroff = 0;
471 struct symtableheader hdr;
473 Vprintf(stdout, "Check pointing the restore\n");
476 if ((fd = fopen(filename, "w")) == NULL) {
478 panic("cannot create save file %s for symbol table\n",
483 * Assign indices to each entry
484 * Write out the string entries
486 for (i = WINO; i <= maxino; i++) {
487 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
488 ep->e_index = mynum++;
489 (void) fwrite(ep->e_name, sizeof(char),
490 (int)allocsize(ep->e_namlen), fd);
494 * Convert pointers to indexes, and output
498 for (i = WINO; i <= maxino; i++) {
499 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
500 memmove(tep, ep, sizeof(struct entry));
501 tep->e_name = (char *)stroff;
502 stroff += allocsize(ep->e_namlen);
503 tep->e_parent = (struct entry *)ep->e_parent->e_index;
504 if (ep->e_links != NULL)
506 (struct entry *)ep->e_links->e_index;
507 if (ep->e_sibling != NULL)
509 (struct entry *)ep->e_sibling->e_index;
510 if (ep->e_entries != NULL)
512 (struct entry *)ep->e_entries->e_index;
513 if (ep->e_next != NULL)
515 (struct entry *)ep->e_next->e_index;
516 (void) fwrite((char *)tep, sizeof(struct entry), 1, fd);
520 * Convert entry pointers to indexes, and output
522 for (i = 0; (long)i < entrytblsize; i++) {
523 if (entry[i] == NULL)
526 tentry = (struct entry *)entry[i]->e_index;
527 (void) fwrite((char *)&tentry, sizeof(struct entry *), 1, fd);
531 hdr.entrytblsize = entrytblsize;
532 hdr.stringsize = stroff;
533 hdr.dumptime = dumptime;
534 hdr.dumpdate = dumpdate;
537 (void) fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd);
540 panic("output error to file %s writing symbol table\n",
547 * Initialize a symbol table from a file
550 initsymtable(char *filename)
555 struct entry *baseep, *lep;
556 struct symtableheader hdr;
561 Vprintf(stdout, "Initialize symbol table.\n");
562 if (filename == NULL) {
563 entrytblsize = maxino / HASHFACTOR;
564 entry = (struct entry **)
565 calloc((unsigned)entrytblsize, sizeof(struct entry *));
566 if (entry == (struct entry **)NULL)
567 errx(1, "no memory for entry table");
568 ep = addentry(".", ROOTINO, NODE);
572 if ((fd = open(filename, O_RDONLY, 0)) < 0) {
574 errx(1, "cannot open symbol table file %s", filename);
576 if (fstat(fd, &stbuf) < 0) {
578 errx(1, "cannot stat symbol table file %s", filename);
580 tblsize = stbuf.st_size - sizeof(struct symtableheader);
581 base = calloc(sizeof(char), (unsigned)tblsize);
583 errx(1, "cannot allocate space for symbol table");
584 if (read(fd, base, (int)tblsize) < 0 ||
585 read(fd, (char *)&hdr, sizeof(struct symtableheader)) < 0) {
587 errx(1, "cannot read symbol table file %s", filename);
592 * For normal continuation, insure that we are using
593 * the next incremental tape
595 if (hdr.dumpdate != dumptime)
596 errx(1, "Incremental tape too %s",
597 (hdr.dumpdate < dumptime) ? "low" : "high");
601 * For restart, insure that we are using the same tape
603 curfile.action = SKIP;
604 dumptime = hdr.dumptime;
605 dumpdate = hdr.dumpdate;
608 newtapebuf(hdr.ntrec);
612 panic("initsymtable called from command %c\n", command);
615 resizemaps(maxino, hdr.maxino);
617 entrytblsize = hdr.entrytblsize;
618 entry = (struct entry **)
619 (base + tblsize - (entrytblsize * sizeof(struct entry *)));
620 baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry));
621 lep = (struct entry *)entry;
622 for (i = 0; i < entrytblsize; i++) {
623 if (entry[i] == NULL)
625 entry[i] = &baseep[(long)entry[i]];
627 for (ep = &baseep[1]; ep < lep; ep++) {
628 ep->e_name = base + (long)ep->e_name;
629 ep->e_parent = &baseep[(long)ep->e_parent];
630 if (ep->e_sibling != NULL)
631 ep->e_sibling = &baseep[(long)ep->e_sibling];
632 if (ep->e_links != NULL)
633 ep->e_links = &baseep[(long)ep->e_links];
634 if (ep->e_entries != NULL)
635 ep->e_entries = &baseep[(long)ep->e_entries];
636 if (ep->e_next != NULL)
637 ep->e_next = &baseep[(long)ep->e_next];