Commit | Line | Data |
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e0519353 | 1 | #ifndef lint |
b97e998a | 2 | static char sccsid[] = "@(#)symtab.c 3.17 (Berkeley) 85/03/24"; |
e0519353 KM |
3 | #endif |
4 | ||
ebd1f727 SL |
5 | /* Copyright (c) 1983 Regents of the University of California */ |
6 | ||
d27b99b5 KM |
7 | /* |
8 | * These routines maintain the symbol table which tracks the state | |
9 | * of the file system being restored. They provide lookup by either | |
10 | * name or inode number. They also provide for creation, deletion, | |
11 | * and renaming of entries. Because of the dynamic nature of pathnames, | |
12 | * names should not be saved, but always constructed just before they | |
13 | * are needed, by calling "myname". | |
14 | */ | |
15 | ||
e0519353 KM |
16 | #include "restore.h" |
17 | #include <sys/stat.h> | |
18 | ||
d27b99b5 KM |
19 | /* |
20 | * The following variables define the inode symbol table. | |
21 | * The primary hash table is dynamically allocated based on | |
22 | * the number of inodes in the file system (maxino), scaled by | |
23 | * HASHFACTOR. The variable "entry" points to the hash table; | |
24 | * the variable "entrytblsize" indicates its size (in entries). | |
25 | */ | |
26 | #define HASHFACTOR 5 | |
a08c9679 KM |
27 | static struct entry **entry; |
28 | static long entrytblsize; | |
e0519353 KM |
29 | |
30 | /* | |
31 | * Look up an entry by inode number | |
32 | */ | |
33 | struct entry * | |
34 | lookupino(inum) | |
35 | ino_t inum; | |
36 | { | |
a08c9679 | 37 | register struct entry *ep; |
e0519353 | 38 | |
a08c9679 KM |
39 | if (inum < ROOTINO || inum >= maxino) |
40 | return (NIL); | |
41 | for (ep = entry[inum % entrytblsize]; ep != NIL; ep = ep->e_next) | |
42 | if (ep->e_ino == inum) | |
43 | return (ep); | |
44 | return (NIL); | |
e0519353 KM |
45 | } |
46 | ||
47 | /* | |
48 | * Add an entry into the entry table | |
49 | */ | |
50 | addino(inum, np) | |
a08c9679 | 51 | ino_t inum; |
e0519353 KM |
52 | struct entry *np; |
53 | { | |
a08c9679 | 54 | struct entry **epp; |
6e466853 | 55 | |
a08c9679 KM |
56 | if (inum < ROOTINO || inum >= maxino) |
57 | panic("addino: out of range %d\n", inum); | |
58 | epp = &entry[inum % entrytblsize]; | |
59 | np->e_ino = inum; | |
60 | np->e_next = *epp; | |
61 | *epp = np; | |
62 | if (dflag) | |
63 | for (np = np->e_next; np != NIL; np = np->e_next) | |
64 | if (np->e_ino == inum) | |
65 | badentry(np, "duplicate inum"); | |
e0519353 KM |
66 | } |
67 | ||
68 | /* | |
69 | * Delete an entry from the entry table | |
70 | */ | |
71 | deleteino(inum) | |
a08c9679 | 72 | ino_t inum; |
e0519353 | 73 | { |
a08c9679 KM |
74 | register struct entry *next; |
75 | struct entry **prev; | |
76 | ||
77 | if (inum < ROOTINO || inum >= maxino) | |
78 | panic("deleteino: out of range %d\n", inum); | |
79 | prev = &entry[inum % entrytblsize]; | |
80 | for (next = *prev; next != NIL; next = next->e_next) { | |
81 | if (next->e_ino == inum) { | |
82 | next->e_ino = 0; | |
83 | *prev = next->e_next; | |
84 | return; | |
85 | } | |
86 | prev = &next->e_next; | |
87 | } | |
88 | panic("deleteino: %d not found\n", inum); | |
e0519353 KM |
89 | } |
90 | ||
91 | /* | |
92 | * Look up an entry by name | |
93 | */ | |
94 | struct entry * | |
95 | lookupname(name) | |
96 | char *name; | |
97 | { | |
98 | register struct entry *ep; | |
99 | register char *np, *cp; | |
d27b99b5 | 100 | char buf[MAXPATHLEN]; |
e0519353 KM |
101 | |
102 | cp = name; | |
103 | for (ep = lookupino(ROOTINO); ep != NIL; ep = ep->e_entries) { | |
104 | for (np = buf; *cp != '/' && *cp != '\0'; ) | |
105 | *np++ = *cp++; | |
106 | *np = '\0'; | |
107 | for ( ; ep != NIL; ep = ep->e_sibling) | |
108 | if (strcmp(ep->e_name, buf) == 0) | |
109 | break; | |
110 | if (ep == NIL) | |
111 | break; | |
9f13f26d | 112 | if (*cp++ == '\0') |
e0519353 KM |
113 | return (ep); |
114 | } | |
9f13f26d | 115 | return (NIL); |
e0519353 KM |
116 | } |
117 | ||
118 | /* | |
119 | * Look up the parent of a pathname | |
120 | */ | |
121 | struct entry * | |
122 | lookupparent(name) | |
123 | char *name; | |
124 | { | |
125 | struct entry *ep; | |
126 | char *tailindex; | |
127 | ||
128 | tailindex = rindex(name, '/'); | |
129 | if (tailindex == 0) | |
130 | return (NIL); | |
131 | *tailindex = '\0'; | |
132 | ep = lookupname(name); | |
9f13f26d | 133 | *tailindex = '/'; |
e0519353 KM |
134 | if (ep == NIL) |
135 | return (NIL); | |
136 | if (ep->e_type != NODE) | |
137 | panic("%s is not a directory\n", name); | |
138 | return (ep); | |
139 | } | |
140 | ||
141 | /* | |
142 | * Determine the current pathname of a node or leaf | |
143 | */ | |
144 | char * | |
145 | myname(ep) | |
146 | register struct entry *ep; | |
147 | { | |
148 | register char *cp; | |
d27b99b5 | 149 | static char namebuf[MAXPATHLEN]; |
e0519353 | 150 | |
d27b99b5 | 151 | for (cp = &namebuf[MAXPATHLEN - 2]; cp > &namebuf[ep->e_namlen]; ) { |
e0519353 KM |
152 | cp -= ep->e_namlen; |
153 | bcopy(ep->e_name, cp, (long)ep->e_namlen); | |
154 | if (ep == lookupino(ROOTINO)) | |
155 | return (cp); | |
156 | *(--cp) = '/'; | |
157 | ep = ep->e_parent; | |
158 | } | |
159 | panic("%s: pathname too long\n", cp); | |
160 | return(cp); | |
161 | } | |
162 | ||
d27b99b5 KM |
163 | /* |
164 | * Unused symbol table entries are linked together on a freelist | |
165 | * headed by the following pointer. | |
166 | */ | |
167 | static struct entry *freelist = NIL; | |
168 | ||
e0519353 KM |
169 | /* |
170 | * add an entry to the symbol table | |
171 | */ | |
172 | struct entry * | |
173 | addentry(name, inum, type) | |
174 | char *name; | |
175 | ino_t inum; | |
176 | int type; | |
177 | { | |
178 | register struct entry *np, *ep; | |
179 | ||
180 | if (freelist != NIL) { | |
181 | np = freelist; | |
a08c9679 | 182 | freelist = np->e_next; |
e0519353 KM |
183 | bzero((char *)np, (long)sizeof(struct entry)); |
184 | } else { | |
185 | np = (struct entry *)calloc(1, sizeof(struct entry)); | |
ad4fabdf KM |
186 | if (np == NIL) |
187 | panic("no memory to extend symbol table\n"); | |
e0519353 | 188 | } |
e0519353 KM |
189 | np->e_type = type & ~LINK; |
190 | ep = lookupparent(name); | |
191 | if (ep == NIL) { | |
192 | if (inum != ROOTINO || lookupino(ROOTINO) != NIL) | |
193 | panic("bad name to addentry %s\n", name); | |
194 | np->e_name = savename(name); | |
195 | np->e_namlen = strlen(name); | |
196 | np->e_parent = np; | |
197 | addino(ROOTINO, np); | |
198 | return (np); | |
199 | } | |
200 | np->e_name = savename(rindex(name, '/') + 1); | |
201 | np->e_namlen = strlen(np->e_name); | |
202 | np->e_parent = ep; | |
203 | np->e_sibling = ep->e_entries; | |
204 | ep->e_entries = np; | |
205 | if (type & LINK) { | |
206 | ep = lookupino(inum); | |
207 | if (ep == NIL) | |
208 | panic("link to non-existant name\n"); | |
b99fe9a4 | 209 | np->e_ino = inum; |
e0519353 KM |
210 | np->e_links = ep->e_links; |
211 | ep->e_links = np; | |
212 | } else if (inum != 0) { | |
213 | if (lookupino(inum) != NIL) | |
214 | panic("duplicate entry\n"); | |
215 | addino(inum, np); | |
216 | } | |
217 | return (np); | |
218 | } | |
219 | ||
220 | /* | |
221 | * delete an entry from the symbol table | |
222 | */ | |
223 | freeentry(ep) | |
224 | register struct entry *ep; | |
225 | { | |
226 | register struct entry *np; | |
40204072 | 227 | ino_t inum; |
e0519353 | 228 | |
e0519353 KM |
229 | if (ep->e_flags != REMOVED) |
230 | badentry(ep, "not marked REMOVED"); | |
a08c9679 KM |
231 | if (ep->e_type == NODE) { |
232 | if (ep->e_links != NIL) | |
e0519353 KM |
233 | badentry(ep, "freeing referenced directory"); |
234 | if (ep->e_entries != NIL) | |
235 | badentry(ep, "freeing non-empty directory"); | |
236 | } | |
a08c9679 KM |
237 | if (ep->e_ino != 0) { |
238 | np = lookupino(ep->e_ino); | |
239 | if (np == NIL) | |
240 | badentry(ep, "lookupino failed"); | |
241 | if (np == ep) { | |
40204072 KM |
242 | inum = ep->e_ino; |
243 | deleteino(inum); | |
a08c9679 | 244 | if (ep->e_links != NIL) |
40204072 | 245 | addino(inum, ep->e_links); |
a08c9679 KM |
246 | } else { |
247 | for (; np != NIL; np = np->e_links) { | |
248 | if (np->e_links == ep) { | |
249 | np->e_links = ep->e_links; | |
250 | break; | |
251 | } | |
e0519353 | 252 | } |
a08c9679 KM |
253 | if (np == NIL) |
254 | badentry(ep, "link not found"); | |
e0519353 | 255 | } |
e0519353 KM |
256 | } |
257 | removeentry(ep); | |
d27b99b5 | 258 | freename(ep->e_name); |
a08c9679 | 259 | ep->e_next = freelist; |
e0519353 KM |
260 | freelist = ep; |
261 | } | |
262 | ||
263 | /* | |
264 | * Relocate an entry in the tree structure | |
265 | */ | |
266 | moveentry(ep, newname) | |
267 | register struct entry *ep; | |
268 | char *newname; | |
269 | { | |
270 | struct entry *np; | |
271 | char *cp; | |
e0519353 KM |
272 | |
273 | np = lookupparent(newname); | |
274 | if (np == NIL) | |
275 | badentry(ep, "cannot move ROOT"); | |
276 | if (np != ep->e_parent) { | |
277 | removeentry(ep); | |
278 | ep->e_parent = np; | |
279 | ep->e_sibling = np->e_entries; | |
280 | np->e_entries = ep; | |
281 | } | |
282 | cp = rindex(newname, '/') + 1; | |
d27b99b5 KM |
283 | freename(ep->e_name); |
284 | ep->e_name = savename(cp); | |
285 | ep->e_namlen = strlen(cp); | |
286 | if (strcmp(gentempname(ep), ep->e_name) == 0) | |
e0519353 KM |
287 | ep->e_flags |= TMPNAME; |
288 | else | |
289 | ep->e_flags &= ~TMPNAME; | |
290 | } | |
291 | ||
292 | /* | |
293 | * Remove an entry in the tree structure | |
294 | */ | |
295 | removeentry(ep) | |
296 | register struct entry *ep; | |
297 | { | |
298 | register struct entry *np; | |
299 | ||
300 | np = ep->e_parent; | |
301 | if (np->e_entries == ep) { | |
302 | np->e_entries = ep->e_sibling; | |
303 | } else { | |
304 | for (np = np->e_entries; np != NIL; np = np->e_sibling) { | |
305 | if (np->e_sibling == ep) { | |
306 | np->e_sibling = ep->e_sibling; | |
307 | break; | |
308 | } | |
309 | } | |
310 | if (np == NIL) | |
311 | badentry(ep, "cannot find entry in parent list"); | |
312 | } | |
313 | } | |
314 | ||
315 | /* | |
d27b99b5 KM |
316 | * Table of unused string entries, sorted by length. |
317 | * | |
318 | * Entries are allocated in STRTBLINCR sized pieces so that names | |
319 | * of similar lengths can use the same entry. The value of STRTBLINCR | |
320 | * is chosen so that every entry has at least enough space to hold | |
321 | * a "struct strtbl" header. Thus every entry can be linked onto an | |
322 | * apprpriate free list. | |
323 | * | |
324 | * NB. The macro "allocsize" below assumes that "struct strhdr" | |
325 | * has a size that is a power of two. | |
326 | */ | |
327 | struct strhdr { | |
328 | struct strhdr *next; | |
329 | }; | |
330 | ||
331 | #define STRTBLINCR (sizeof(struct strhdr)) | |
332 | #define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1)) | |
333 | ||
334 | static struct strhdr strtblhdr[allocsize(MAXNAMLEN) / STRTBLINCR]; | |
335 | ||
336 | /* | |
337 | * Allocate space for a name. It first looks to see if it already | |
338 | * has an appropriate sized entry, and if not allocates a new one. | |
e0519353 KM |
339 | */ |
340 | char * | |
341 | savename(name) | |
342 | char *name; | |
343 | { | |
d27b99b5 | 344 | struct strhdr *np; |
e0519353 | 345 | long len; |
9f13f26d | 346 | char *cp; |
e0519353 KM |
347 | |
348 | if (name == NULL) | |
349 | panic("bad name\n"); | |
d27b99b5 KM |
350 | len = strlen(name); |
351 | np = strtblhdr[len / STRTBLINCR].next; | |
352 | if (np != NULL) { | |
353 | strtblhdr[len / STRTBLINCR].next = np->next; | |
354 | cp = (char *)np; | |
355 | } else { | |
356 | cp = malloc((unsigned)allocsize(len)); | |
357 | if (cp == NULL) | |
358 | panic("no space for string table\n"); | |
359 | } | |
a08c9679 | 360 | (void) strcpy(cp, name); |
9f13f26d | 361 | return (cp); |
e0519353 KM |
362 | } |
363 | ||
d27b99b5 KM |
364 | /* |
365 | * Free space for a name. The resulting entry is linked onto the | |
366 | * appropriate free list. | |
367 | */ | |
368 | freename(name) | |
369 | char *name; | |
370 | { | |
371 | struct strhdr *tp, *np; | |
372 | ||
373 | tp = &strtblhdr[strlen(name) / STRTBLINCR]; | |
374 | np = (struct strhdr *)name; | |
375 | np->next = tp->next; | |
376 | tp->next = np; | |
377 | } | |
378 | ||
379 | /* | |
380 | * Useful quantities placed at the end of a dumped symbol table. | |
381 | */ | |
382 | struct symtableheader { | |
383 | long volno; | |
384 | long stringsize; | |
385 | long entrytblsize; | |
386 | time_t dumptime; | |
387 | time_t dumpdate; | |
388 | ino_t maxino; | |
b97e998a | 389 | long ntrec; |
d27b99b5 KM |
390 | }; |
391 | ||
e0519353 KM |
392 | /* |
393 | * dump a snapshot of the symbol table | |
394 | */ | |
395 | dumpsymtable(filename, checkpt) | |
396 | char *filename; | |
397 | long checkpt; | |
398 | { | |
a08c9679 KM |
399 | register struct entry *ep, *tep; |
400 | register ino_t i; | |
401 | struct entry temp, *tentry; | |
402 | long mynum = 1, stroff = 0; | |
e0519353 KM |
403 | FILE *fd; |
404 | struct symtableheader hdr; | |
405 | ||
406 | vprintf(stdout, "Check pointing the restore\n"); | |
407 | if ((fd = fopen(filename, "w")) == NULL) { | |
408 | perror("fopen"); | |
409 | panic("cannot create save file %s for symbol table\n", | |
410 | filename); | |
411 | } | |
412 | clearerr(fd); | |
413 | /* | |
414 | * Assign indicies to each entry | |
415 | * Write out the string entries | |
416 | */ | |
417 | for (i = ROOTINO; i < maxino; i++) { | |
418 | for (ep = lookupino(i); ep != NIL; ep = ep->e_links) { | |
a08c9679 | 419 | ep->e_index = mynum++; |
e9a184e3 KM |
420 | (void) fwrite(ep->e_name, sizeof(char), |
421 | (int)allocsize(ep->e_namlen), fd); | |
e0519353 KM |
422 | } |
423 | } | |
e0519353 KM |
424 | /* |
425 | * Convert pointers to indexes, and output | |
426 | */ | |
a08c9679 KM |
427 | tep = &temp; |
428 | stroff = 0; | |
e0519353 | 429 | for (i = ROOTINO; i < maxino; i++) { |
a08c9679 | 430 | for (ep = lookupino(i); ep != NIL; ep = ep->e_links) { |
e9a184e3 KM |
431 | bcopy((char *)ep, (char *)tep, |
432 | (long)sizeof(struct entry)); | |
a08c9679 | 433 | tep->e_name = (char *)stroff; |
d27b99b5 | 434 | stroff += allocsize(ep->e_namlen); |
a08c9679 KM |
435 | tep->e_parent = (struct entry *)ep->e_parent->e_index; |
436 | if (ep->e_links != NIL) | |
437 | tep->e_links = | |
438 | (struct entry *)ep->e_links->e_index; | |
439 | if (ep->e_sibling != NIL) | |
440 | tep->e_sibling = | |
441 | (struct entry *)ep->e_sibling->e_index; | |
442 | if (ep->e_entries != NIL) | |
443 | tep->e_entries = | |
444 | (struct entry *)ep->e_entries->e_index; | |
445 | if (ep->e_next != NIL) | |
446 | tep->e_next = | |
447 | (struct entry *)ep->e_next->e_index; | |
e9a184e3 | 448 | (void) fwrite((char *)tep, sizeof(struct entry), 1, fd); |
e0519353 KM |
449 | } |
450 | } | |
a08c9679 KM |
451 | /* |
452 | * Convert entry pointers to indexes, and output | |
453 | */ | |
454 | for (i = 0; i < entrytblsize; i++) { | |
455 | if (entry[i] == NIL) | |
456 | tentry = NIL; | |
457 | else | |
458 | tentry = (struct entry *)entry[i]->e_index; | |
e9a184e3 | 459 | (void) fwrite((char *)&tentry, sizeof(struct entry *), 1, fd); |
a08c9679 | 460 | } |
e0519353 KM |
461 | hdr.volno = checkpt; |
462 | hdr.maxino = maxino; | |
a08c9679 | 463 | hdr.entrytblsize = entrytblsize; |
d27b99b5 | 464 | hdr.stringsize = stroff; |
2cb5dabb KM |
465 | hdr.dumptime = dumptime; |
466 | hdr.dumpdate = dumpdate; | |
b97e998a | 467 | hdr.ntrec = ntrec; |
e9a184e3 | 468 | (void) fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd); |
e0519353 KM |
469 | if (ferror(fd)) { |
470 | perror("fwrite"); | |
471 | panic("output error to file %s writing symbol table\n", | |
472 | filename); | |
473 | } | |
e9a184e3 | 474 | (void) fclose(fd); |
e0519353 KM |
475 | } |
476 | ||
477 | /* | |
478 | * Initialize a symbol table from a file | |
479 | */ | |
480 | initsymtable(filename) | |
481 | char *filename; | |
482 | { | |
483 | char *base; | |
484 | long tblsize; | |
485 | register struct entry *ep; | |
486 | struct entry *baseep, *lep; | |
487 | struct symtableheader hdr; | |
488 | struct stat stbuf; | |
489 | register long i; | |
490 | int fd; | |
491 | ||
492 | vprintf(stdout, "Initialize symbol table.\n"); | |
a08c9679 KM |
493 | if (filename == NULL) { |
494 | entrytblsize = maxino / HASHFACTOR; | |
495 | entry = (struct entry **) | |
496 | calloc((unsigned)entrytblsize, sizeof(struct entry *)); | |
497 | if (entry == (struct entry **)NIL) | |
498 | panic("no memory for entry table\n"); | |
021e989e KM |
499 | ep = addentry(".", ROOTINO, NODE); |
500 | ep->e_flags |= NEW; | |
a08c9679 KM |
501 | return; |
502 | } | |
e0519353 KM |
503 | if ((fd = open(filename, 0)) < 0) { |
504 | perror("open"); | |
505 | panic("cannot open symbol table file %s\n", filename); | |
506 | } | |
507 | if (fstat(fd, &stbuf) < 0) { | |
508 | perror("stat"); | |
509 | panic("cannot stat symbol table file %s\n", filename); | |
510 | } | |
511 | tblsize = stbuf.st_size - sizeof(struct symtableheader); | |
4b05a065 | 512 | base = calloc(sizeof(char), (unsigned)tblsize); |
e0519353 KM |
513 | if (base == NULL) |
514 | panic("cannot allocate space for symbol table\n"); | |
515 | if (read(fd, base, (int)tblsize) < 0 || | |
516 | read(fd, (char *)&hdr, sizeof(struct symtableheader)) < 0) { | |
517 | perror("read"); | |
518 | panic("cannot read symbol table file %s\n", filename); | |
519 | } | |
2cb5dabb KM |
520 | switch (command) { |
521 | case 'r': | |
522 | /* | |
523 | * For normal continuation, insure that we are using | |
524 | * the next incremental tape | |
525 | */ | |
a08c9679 KM |
526 | if (hdr.dumpdate != dumptime) { |
527 | if (hdr.dumpdate < dumptime) | |
2cb5dabb KM |
528 | fprintf(stderr, "Incremental tape too low\n"); |
529 | else | |
530 | fprintf(stderr, "Incremental tape too high\n"); | |
531 | done(1); | |
532 | } | |
533 | break; | |
534 | case 'R': | |
535 | /* | |
536 | * For restart, insure that we are using the same tape | |
537 | */ | |
e108d3a2 KM |
538 | curfile.action = SKIP; |
539 | dumptime = hdr.dumptime; | |
540 | dumpdate = hdr.dumpdate; | |
b97e998a KM |
541 | if (!bflag) |
542 | newtapebuf(hdr.ntrec); | |
e108d3a2 | 543 | getvol(hdr.volno); |
2cb5dabb KM |
544 | break; |
545 | default: | |
546 | panic("initsymtable called from command %c\n", command); | |
547 | break; | |
548 | } | |
e0519353 | 549 | maxino = hdr.maxino; |
a08c9679 KM |
550 | entrytblsize = hdr.entrytblsize; |
551 | entry = (struct entry **) | |
552 | (base + tblsize - (entrytblsize * sizeof(struct entry *))); | |
553 | baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry)); | |
554 | lep = (struct entry *)entry; | |
555 | for (i = 0; i < entrytblsize; i++) { | |
e0519353 KM |
556 | if (entry[i] == NIL) |
557 | continue; | |
558 | entry[i] = &baseep[(long)entry[i]]; | |
559 | } | |
a08c9679 | 560 | for (ep = &baseep[1]; ep < lep; ep++) { |
e0519353 KM |
561 | ep->e_name = base + (long)ep->e_name; |
562 | ep->e_parent = &baseep[(long)ep->e_parent]; | |
a08c9679 KM |
563 | if (ep->e_sibling != NIL) |
564 | ep->e_sibling = &baseep[(long)ep->e_sibling]; | |
565 | if (ep->e_links != NIL) | |
566 | ep->e_links = &baseep[(long)ep->e_links]; | |
567 | if (ep->e_entries != NIL) | |
568 | ep->e_entries = &baseep[(long)ep->e_entries]; | |
569 | if (ep->e_next != NIL) | |
570 | ep->e_next = &baseep[(long)ep->e_next]; | |
e0519353 KM |
571 | } |
572 | } |