/* $NetBSD: restore.c,v 1.20 2006/12/18 20:07:32 christos Exp $ */ /* * Copyright (c) 1983, 1993 * The Regents of the University of California. 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. * 3. 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. */ #include #ifndef lint #if 0 static char sccsid[] = "@(#)restore.c 8.3 (Berkeley) 9/13/94"; #else __RCSID("$NetBSD: restore.c,v 1.20 2006/12/18 20:07:32 christos Exp $"); #endif #endif /* not lint */ #include #include #include #include #include #include "restore.h" #include "extern.h" static char *keyval(int); /* * This implements the 't' option. * List entries on the tape. */ long listfile(const char *name, ino_t ino, int type) { long descend = hflag ? GOOD : FAIL; if (TSTINO(ino, dumpmap) == 0) return (descend); vprintf(stdout, "%s", type == LEAF ? "leaf" : "dir "); fprintf(stdout, "%10llu\t%s\n", (unsigned long long)ino, name); return (descend); } /* * This implements the 'x' option. * Request that new entries be extracted. */ long addfile(const char *name, ino_t ino, int type) { struct entry *ep; long descend = hflag ? GOOD : FAIL; char buf[100]; if (TSTINO(ino, dumpmap) == 0) { dprintf(stdout, "%s: not on the tape\n", name); return (descend); } if (ino == WINO && command == 'i' && !vflag) return (descend); if (!mflag) { (void) snprintf(buf, sizeof(buf), "./%llu", (unsigned long long)ino); name = buf; if (type == NODE) { (void) genliteraldir(name, ino); return (descend); } } ep = lookupino(ino); if (ep != NULL) { if (strcmp(name, myname(ep)) == 0) { ep->e_flags |= NEW; return (descend); } type |= LINK; } ep = addentry(name, ino, type); if (type == NODE) newnode(ep); ep->e_flags |= NEW; return (descend); } /* * This is used by the 'i' option to undo previous requests made by addfile. * Delete entries from the request queue. */ /* ARGSUSED */ long deletefile(const char *name, ino_t ino, int type __unused) { long descend = hflag ? GOOD : FAIL; struct entry *ep; if (TSTINO(ino, dumpmap) == 0) return (descend); ep = lookupname(name); if (ep != NULL) { ep->e_flags &= ~NEW; ep->e_flags |= REMOVED; if (ep->e_type != NODE) freeentry(ep); } return (descend); } /* * The following four routines implement the incremental * restore algorithm. The first removes old entries, the second * does renames and calculates the extraction list, the third * cleans up link names missed by the first two, and the final * one deletes old directories. * * Directories cannot be immediately deleted, as they may have * other files in them which need to be moved out first. As * directories to be deleted are found, they are put on the * following deletion list. After all deletions and renames * are done, this list is actually deleted. */ static struct entry *removelist; /* * Remove invalid whiteouts from the old tree. * Remove unneeded leaves from the old tree. * Remove directories from the lookup chains. */ void removeoldleaves(void) { struct entry *ep, *nextep; ino_t i, mydirino; vprintf(stdout, "Mark entries to be removed.\n"); if ((ep = lookupino(WINO)) != NULL) { vprintf(stdout, "Delete whiteouts\n"); for ( ; ep != NULL; ep = nextep) { nextep = ep->e_links; mydirino = ep->e_parent->e_ino; /* * We remove all whiteouts that are in directories * that have been removed or that have been dumped. */ if (TSTINO(mydirino, usedinomap) && !TSTINO(mydirino, dumpmap)) continue; delwhiteout(ep); freeentry(ep); } } for (i = ROOTINO + 1; i < maxino; i++) { ep = lookupino(i); if (ep == NULL) continue; if (TSTINO(i, usedinomap)) continue; for ( ; ep != NULL; ep = ep->e_links) { dprintf(stdout, "%s: REMOVE\n", myname(ep)); if (ep->e_type == LEAF) { removeleaf(ep); freeentry(ep); } else { mktempname(ep); deleteino(ep->e_ino); ep->e_next = removelist; removelist = ep; } } } } /* * For each directory entry on the incremental tape, determine which * category it falls into as follows: * KEEP - entries that are to be left alone. * NEW - new entries to be added. * EXTRACT - files that must be updated with new contents. * LINK - new links to be added. * Renames are done at the same time. */ long nodeupdates(const char *name, ino_t ino, int type) { struct entry *ep, *np, *ip; long descend = GOOD; int lookuptype = 0; int key = 0; /* key values */ # define ONTAPE 0x1 /* inode is on the tape */ # define INOFND 0x2 /* inode already exists */ # define NAMEFND 0x4 /* name already exists */ # define MODECHG 0x8 /* mode of inode changed */ /* * This routine is called once for each element in the * directory hierarchy, with a full path name. * The "type" value is incorrectly specified as LEAF for * directories that are not on the dump tape. * * Check to see if the file is on the tape. */ if (TSTINO(ino, dumpmap)) key |= ONTAPE; /* * Check to see if the name exists, and if the name is a link. */ np = lookupname(name); if (np != NULL) { key |= NAMEFND; ip = lookupino(np->e_ino); if (ip == NULL) panic("corrupted symbol table\n"); if (ip != np) lookuptype = LINK; } /* * Check to see if the inode exists, and if one of its links * corresponds to the name (if one was found). */ ip = lookupino(ino); if (ip != NULL) { key |= INOFND; for (ep = ip->e_links; ep != NULL; ep = ep->e_links) { if (ep == np) { ip = ep; break; } } } /* * If both a name and an inode are found, but they do not * correspond to the same file, then both the inode that has * been found and the inode corresponding to the name that * has been found need to be renamed. The current pathname * is the new name for the inode that has been found. Since * all files to be deleted have already been removed, the * named file is either a now unneeded link, or it must live * under a new name in this dump level. If it is a link, it * can be removed. If it is not a link, it is given a * temporary name in anticipation that it will be renamed * when it is later found by inode number. */ if (((key & (INOFND|NAMEFND)) == (INOFND|NAMEFND)) && ip != np) { if (lookuptype == LINK) { removeleaf(np); freeentry(np); } else { dprintf(stdout, "name/inode conflict, mktempname %s\n", myname(np)); mktempname(np); } np = NULL; key &= ~NAMEFND; } if ((key & ONTAPE) && (((key & INOFND) && ip->e_type != type) || ((key & NAMEFND) && np->e_type != type))) key |= MODECHG; /* * Decide on the disposition of the file based on its flags. * Note that we have already handled the case in which * a name and inode are found that correspond to different files. * Thus if both NAMEFND and INOFND are set then ip == np. */ switch (key) { /* * A previously existing file has been found. * Mark it as KEEP so that other links to the inode can be * detected, and so that it will not be reclaimed by the search * for unreferenced names. */ case INOFND|NAMEFND: ip->e_flags |= KEEP; dprintf(stdout, "[%s] %s: %s\n", keyval(key), name, flagvalues(ip)); break; /* * A file on the tape has a name which is the same as a name * corresponding to a different file in the previous dump. * Since all files to be deleted have already been removed, * this file is either a now unneeded link, or it must live * under a new name in this dump level. If it is a link, it * can simply be removed. If it is not a link, it is given a * temporary name in anticipation that it will be renamed * when it is later found by inode number (see INOFND case * below). The entry is then treated as a new file. */ case ONTAPE|NAMEFND: case ONTAPE|NAMEFND|MODECHG: if (lookuptype == LINK) { removeleaf(np); freeentry(np); } else { mktempname(np); } /* fall through */ /* * A previously non-existent file. * Add it to the file system, and request its extraction. * If it is a directory, create it immediately. * (Since the name is unused there can be no conflict) */ case ONTAPE: ep = addentry(name, ino, type); if (type == NODE) newnode(ep); ep->e_flags |= NEW|KEEP; dprintf(stdout, "[%s] %s: %s\n", keyval(key), name, flagvalues(ep)); break; /* * A file with the same inode number, but a different * name has been found. If the other name has not already * been found (indicated by the KEEP flag, see above) then * this must be a new name for the file, and it is renamed. * If the other name has been found then this must be a * link to the file. Hard links to directories are not * permitted, and are either deleted or converted to * symbolic links. Finally, if the file is on the tape, * a request is made to extract it. */ case ONTAPE|INOFND: if (type == LEAF && (ip->e_flags & KEEP) == 0) ip->e_flags |= EXTRACT; /* fall through */ case INOFND: if ((ip->e_flags & KEEP) == 0) { renameit(myname(ip), name); moveentry(ip, name); ip->e_flags |= KEEP; dprintf(stdout, "[%s] %s: %s\n", keyval(key), name, flagvalues(ip)); break; } if (ip->e_type == NODE) { descend = FAIL; fprintf(stderr, "deleted hard link %s to directory %s\n", name, myname(ip)); break; } ep = addentry(name, ino, type|LINK); ep->e_flags |= NEW; dprintf(stdout, "[%s] %s: %s|LINK\n", keyval(key), name, flagvalues(ep)); break; /* * A previously known file which is to be updated. If it is a link, * then all names referring to the previous file must be removed * so that the subset of them that remain can be recreated. */ case ONTAPE|INOFND|NAMEFND: if (lookuptype == LINK) { removeleaf(np); freeentry(np); ep = addentry(name, ino, type|LINK); if (type == NODE) newnode(ep); ep->e_flags |= NEW|KEEP; dprintf(stdout, "[%s] %s: %s|LINK\n", keyval(key), name, flagvalues(ep)); break; } if (type == LEAF && lookuptype != LINK) np->e_flags |= EXTRACT; np->e_flags |= KEEP; dprintf(stdout, "[%s] %s: %s\n", keyval(key), name, flagvalues(np)); break; /* * An inode is being reused in a completely different way. * Normally an extract can simply do an "unlink" followed * by a "creat". Here we must do effectively the same * thing. The complications arise because we cannot really * delete a directory since it may still contain files * that we need to rename, so we delete it from the symbol * table, and put it on the list to be deleted eventually. * Conversely if a directory is to be created, it must be * done immediately, rather than waiting until the * extraction phase. */ case ONTAPE|INOFND|MODECHG: case ONTAPE|INOFND|NAMEFND|MODECHG: if (ip->e_flags & KEEP) { badentry(ip, "cannot KEEP and change modes"); break; } if (ip->e_type == LEAF) { /* changing from leaf to node */ for ( ; ip != NULL; ip = ip->e_links) { if (ip->e_type != LEAF) badentry(ip, "NODE and LEAF links to same inode"); removeleaf(ip); freeentry(ip); } ip = addentry(name, ino, type); newnode(ip); } else { /* changing from node to leaf */ if ((ip->e_flags & TMPNAME) == 0) mktempname(ip); deleteino(ip->e_ino); ip->e_next = removelist; removelist = ip; ip = addentry(name, ino, type); } ip->e_flags |= NEW|KEEP; dprintf(stdout, "[%s] %s: %s\n", keyval(key), name, flagvalues(ip)); break; /* * A hard link to a diirectory that has been removed. * Ignore it. */ case NAMEFND: dprintf(stdout, "[%s] %s: Extraneous name\n", keyval(key), name); descend = FAIL; break; /* * If we find a directory entry for a file that is not on * the tape, then we must have found a file that was created * while the dump was in progress. Since we have no contents * for it, we discard the name knowing that it will be on the * next incremental tape. */ case 0: fprintf(stderr, "%s: (inode %llu) not found on tape\n", name, (unsigned long long)ino); break; /* * If any of these arise, something is grievously wrong with * the current state of the symbol table. */ case INOFND|NAMEFND|MODECHG: case NAMEFND|MODECHG: case INOFND|MODECHG: fprintf(stderr, "[%s] %s: inconsistent state\n", keyval(key), name); break; /* * These states "cannot" arise for any state of the symbol table. */ case ONTAPE|MODECHG: case MODECHG: default: panic("[%s] %s: impossible state\n", keyval(key), name); break; } return (descend); } /* * Calculate the active flags in a key. */ static char * keyval(int key) { static char keybuf[32]; (void) strcpy(keybuf, "|NIL"); keybuf[0] = '\0'; if (key & ONTAPE) (void) strcat(keybuf, "|ONTAPE"); if (key & INOFND) (void) strcat(keybuf, "|INOFND"); if (key & NAMEFND) (void) strcat(keybuf, "|NAMEFND"); if (key & MODECHG) (void) strcat(keybuf, "|MODECHG"); return (&keybuf[1]); } /* * Find unreferenced link names. */ void findunreflinks(void) { struct entry *ep, *np; ino_t i; vprintf(stdout, "Find unreferenced names.\n"); for (i = ROOTINO; i < maxino; i++) { ep = lookupino(i); if (ep == NULL || ep->e_type == LEAF || TSTINO(i, dumpmap) == 0) continue; for (np = ep->e_entries; np != NULL; np = np->e_sibling) { if (np->e_flags == 0) { dprintf(stdout, "%s: remove unreferenced name\n", myname(np)); removeleaf(np); freeentry(np); } } } /* * Any leaves remaining in removed directories is unreferenced. */ for (ep = removelist; ep != NULL; ep = ep->e_next) { for (np = ep->e_entries; np != NULL; np = np->e_sibling) { if (np->e_type == LEAF) { if (np->e_flags != 0) badentry(np, "unreferenced with flags"); dprintf(stdout, "%s: remove unreferenced name\n", myname(np)); removeleaf(np); freeentry(np); } } } } /* * Remove old nodes (directories). * Note that this routine runs in O(N*D) where: * N is the number of directory entries to be removed. * D is the maximum depth of the tree. * If N == D this can be quite slow. If the list were * topologically sorted, the deletion could be done in * time O(N). */ void removeoldnodes(void) { struct entry *ep, **prev; long change; vprintf(stdout, "Remove old nodes (directories).\n"); do { change = 0; prev = &removelist; for (ep = removelist; ep != NULL; ep = *prev) { if (ep->e_entries != NULL) { prev = &ep->e_next; continue; } *prev = ep->e_next; removenode(ep); freeentry(ep); change++; } } while (change); for (ep = removelist; ep != NULL; ep = ep->e_next) badentry(ep, "cannot remove, non-empty"); } /* * This is the routine used to extract files for the 'r' command. * Extract new leaves. */ void createleaves(const char *symtabfile) { struct entry *ep; ino_t first; long curvol; if (command == 'R') { vprintf(stdout, "Continue extraction of new leaves\n"); } else { vprintf(stdout, "Extract new leaves.\n"); dumpsymtable(symtabfile, volno); } first = lowerbnd(ROOTINO); curvol = volno; while (curfile.ino < maxino) { first = lowerbnd(first); /* * If the next available file is not the one which we * expect then we have missed one or more files. Since * we do not request files that were not on the tape, * the lost files must have been due to a tape read error, * or a file that was removed while the dump was in progress. */ while (first < curfile.ino) { ep = lookupino(first); if (ep == NULL) panic("%llu: bad first\n", (unsigned long long)first); fprintf(stderr, "%s: not found on tape\n", myname(ep)); ep->e_flags &= ~(NEW|EXTRACT); first = lowerbnd(first); } /* * If we find files on the tape that have no corresponding * directory entries, then we must have found a file that * was created while the dump was in progress. Since we have * no name for it, we discard it knowing that it will be * on the next incremental tape. */ if (first != curfile.ino) { fprintf(stderr, "expected next file %llu, got %llu\n", (unsigned long long)first, (unsigned long long)curfile.ino); skipfile(); goto next; } ep = lookupino(curfile.ino); if (ep == NULL) panic("unknown file on tape\n"); if ((ep->e_flags & (NEW|EXTRACT)) == 0) badentry(ep, "unexpected file on tape"); /* * If the file is to be extracted, then the old file must * be removed since its type may change from one leaf type * to another (eg "file" to "character special"). */ if ((ep->e_flags & EXTRACT) != 0) { removeleaf(ep); ep->e_flags &= ~REMOVED; } (void) extractfile(myname(ep)); ep->e_flags &= ~(NEW|EXTRACT); /* * We checkpoint the restore after every tape reel, so * as to simplify the amount of work re quired by the * 'R' command. */ next: if (curvol != volno) { dumpsymtable(symtabfile, volno); skipmaps(); curvol = volno; } } } /* * This is the routine used to extract files for the 'x' and 'i' commands. * Efficiently extract a subset of the files on a tape. */ void createfiles(void) { ino_t first, next, last; struct entry *ep; long curvol; vprintf(stdout, "Extract requested files\n"); curfile.action = SKIP; getvol((long)1); skipmaps(); skipdirs(); first = lowerbnd(ROOTINO); last = upperbnd(maxino - 1); new_volume: /* * Decide on the next inode needed in this volume. */ next = lowerbnd(curfile.ino); for (;;) { first = lowerbnd(first); last = upperbnd(last); /* * Check to see if any files remain to be extracted */ if (first > last) return; /* * Reject any volumes with inodes greater * than the last one needed */ if (curfile.ino > last) { do { curfile.action = SKIP; getvol((long)0); skipmaps(); skipdirs(); } while (curfile.ino > last); goto new_volume; } /* * Skip across the inodes until the next inode is found * or an out of order volume change is encountered */ do { curvol = volno; while (next > curfile.ino && volno == curvol) skipfile(); skipmaps(); skipdirs(); } while (volno == curvol + 1); /* * If volume change out of order occurred the * current state must be recalculated */ if (volno != curvol) goto new_volume; /* * If the current inode is greater than the one we were * looking for then we missed the one we were looking for. * Since we only attempt to extract files listed in the * dump map, the lost files must have been due to a tape * read error, or a file that was removed while the dump * was in progress. Thus we report all requested files * between the one we were looking for, and the one we * found as missing, and delete their request flags. */ while (next < curfile.ino) { ep = lookupino(next); if (ep == NULL) panic("corrupted symbol table\n"); fprintf(stderr, "%s: not found on tape\n", myname(ep)); ep->e_flags &= ~NEW; next = lowerbnd(next); } /* * The current inode is the one that we are looking for, * so extract it per its requested name. */ if (next == curfile.ino && next <= last) { ep = lookupino(next); if (ep == NULL) panic("corrupted symbol table\n"); (void) extractfile(myname(ep)); ep->e_flags &= ~NEW; if (volno != curvol) { skipmaps(); goto new_volume; } /* * Decide the next inode. Note that curfile.ino * already updated to the next file on the tape, * and we can't used it since it may be greater * than `next'. */ next = lowerbnd(next); } } } /* * Add links. */ void createlinks(void) { struct entry *np, *ep; ino_t i; char name[BUFSIZ]; if ((ep = lookupino(WINO)) != NULL) { vprintf(stdout, "Add whiteouts\n"); for ( ; ep != NULL; ep = ep->e_links) { if ((ep->e_flags & NEW) == 0) continue; (void) addwhiteout(myname(ep)); ep->e_flags &= ~NEW; } } vprintf(stdout, "Add links\n"); for (i = ROOTINO; i < maxino; i++) { ep = lookupino(i); if (ep == NULL) continue; for (np = ep->e_links; np != NULL; np = np->e_links) { if ((np->e_flags & NEW) == 0) continue; (void) strcpy(name, myname(ep)); if (ep->e_type == NODE) { (void) linkit(name, myname(np), SYMLINK); } else { (void) linkit(name, myname(np), HARDLINK); } np->e_flags &= ~NEW; } } } /* * Check the symbol table. * We do this to insure that all the requested work was done, and * that no temporary names remain. */ void checkrestore(void) { struct entry *ep; ino_t i; vprintf(stdout, "Check the symbol table.\n"); for (i = WINO; i < maxino; i++) { for (ep = lookupino(i); ep != NULL; ep = ep->e_links) { ep->e_flags &= ~KEEP; if (ep->e_type == NODE) ep->e_flags &= ~(NEW|EXISTED); if (ep->e_flags != 0) badentry(ep, "incomplete operations"); } } } /* * Compare with the directory structure on the tape * A paranoid check that things are as they should be. */ long verifyfile(const char *name, ino_t ino, int type) { struct entry *np, *ep; long descend = GOOD; ep = lookupname(name); if (ep == NULL) { fprintf(stderr, "Warning: missing name %s\n", name); return (FAIL); } np = lookupino(ino); if (np != ep) descend = FAIL; for ( ; np != NULL; np = np->e_links) if (np == ep) break; if (np == NULL) panic("missing inumber %llu\n", (unsigned long long)ino); if (ep->e_type == LEAF && type != LEAF) badentry(ep, "type should be LEAF"); return (descend); }