/* * Remove an entry in the tree structure */ static void removeentry(struct entry *ep) { struct entry *np; np = ep->e_parent; if (np->e_entries == ep) { np->e_entries = ep->e_sibling; } else { for (np = np->e_entries; np != NULL; np = np->e_sibling) { if (np->e_sibling == ep) { np->e_sibling = ep->e_sibling; break; } } if (np == NULL) badentry(ep, "cannot find entry in parent list"); } }
/* * 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); } } } }
/* * Compare with the directory structure on the tape * A paranoid check that things are as they should be. */ long verifyfile(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 %ju\n", (uintmax_t)ino); if (ep->e_type == LEAF && type != LEAF) badentry(ep, "type should be LEAF"); return (descend); }
/* * Relocate an entry in the tree structure */ void moveentry(struct entry *ep, char *newname) { struct entry *np; char *cp; np = lookupparent(newname); if (np == NULL) badentry(ep, "cannot move ROOT"); if (np != ep->e_parent) { removeentry(ep); ep->e_parent = np; ep->e_sibling = np->e_entries; np->e_entries = ep; } cp = strrchr(newname, '/') + 1; freename(ep->e_name); ep->e_name = savename(cp); ep->e_namlen = strlen(cp); if (strcmp(gentempname(ep), ep->e_name) == 0) ep->e_flags |= TMPNAME; else ep->e_flags &= ~TMPNAME; }
/* * 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(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("%ju: bad first\n", (uintmax_t)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 %ju, got %ju\n", (uintmax_t)first, (uintmax_t)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 (e.g. "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 required by the * 'R' command. */ next: if (curvol != volno) { dumpsymtable(symtabfile, volno); skipmaps(); curvol = volno; } } }
/* * 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(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); } /* FALLTHROUGH */ /* * 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; /* FALLTHROUGH */ 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 = lookupino(ino); 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 directory 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 %ju) not found on tape\n", name, (uintmax_t)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); }