Commit | Line | Data |
---|---|---|
15637ed4 RG |
1 | /* |
2 | * Written by Paul Popelka (paulp@uts.amdahl.com) | |
3 | * | |
4 | * You can do anything you want with this software, | |
5 | * just don't say you wrote it, | |
6 | * and don't remove this notice. | |
7 | * | |
8 | * This software is provided "as is". | |
9 | * | |
10 | * The author supplies this software to be publicly | |
11 | * redistributed on the understanding that the author | |
12 | * is not responsible for the correct functioning of | |
13 | * this software in any circumstances and is not liable | |
14 | * for any damages caused by this software. | |
15 | * | |
16 | * October 1992 | |
17 | * | |
fde1aeb2 | 18 | * $Id: pcfs_lookup.c,v 1.6 1993/11/25 01:37:12 wollman Exp $ |
15637ed4 RG |
19 | */ |
20 | ||
21 | #include "param.h" | |
dd18dc33 | 22 | #include "systm.h" |
15637ed4 RG |
23 | #include "namei.h" |
24 | #include "buf.h" | |
25 | #include "vnode.h" | |
26 | #include "mount.h" | |
27 | ||
28 | #include "bpb.h" | |
29 | #include "direntry.h" | |
30 | #include "denode.h" | |
31 | #include "pcfsmount.h" | |
32 | #include "fat.h" | |
33 | ||
34 | /* | |
35 | * When we search a directory the blocks containing directory | |
36 | * entries are read and examined. The directory entries | |
37 | * contain information that would normally be in the inode | |
38 | * of a unix filesystem. This means that some of a directory's | |
39 | * contents may also be in memory resident denodes (sort of | |
40 | * an inode). This can cause problems if we are searching | |
41 | * while some other process is modifying a directory. To | |
42 | * prevent one process from accessing incompletely modified | |
43 | * directory information we depend upon being the soul owner | |
44 | * of a directory block. bread/brelse provide this service. | |
45 | * This being the case, when a process modifies a directory | |
46 | * it must first acquire the disk block that contains the | |
47 | * directory entry to be modified. Then update the disk | |
48 | * block and the denode, and then write the disk block out | |
49 | * to disk. This way disk blocks containing directory | |
50 | * entries and in memory denode's will be in synch. | |
51 | */ | |
52 | int | |
53 | pcfs_lookup(vdp, ndp, p) | |
54 | struct vnode *vdp; /* vnode of directory to search */ | |
55 | struct nameidata *ndp; | |
56 | struct proc *p; | |
57 | { | |
58 | daddr_t bn; | |
59 | int flag; | |
60 | int error; | |
61 | int lockparent; | |
62 | int wantparent; | |
63 | int slotstatus; | |
64 | #define NONE 0 | |
65 | #define FOUND 1 | |
4c45483e GW |
66 | int slotoffset = 0; |
67 | int slotcluster = 0; | |
15637ed4 RG |
68 | int frcn; |
69 | u_long cluster; | |
70 | int rootreloff; | |
71 | int diroff; | |
72 | int isadir; /* ~0 if found direntry is a directory */ | |
73 | u_long scn; /* starting cluster number */ | |
74 | struct denode *dp; | |
75 | struct denode *pdp; | |
76 | struct denode *tdp; | |
77 | struct pcfsmount *pmp; | |
78 | struct buf *bp = 0; | |
4c45483e | 79 | struct direntry *dep = 0; |
15637ed4 RG |
80 | u_char dosfilename[12]; |
81 | ||
82 | #if defined(PCFSDEBUG) | |
83 | printf("pcfs_lookup(): looking for %s\n", ndp->ni_ptr); | |
84 | #endif /* defined(PCFSDEBUG) */ | |
85 | ndp->ni_dvp = vdp; | |
86 | ndp->ni_vp = NULL; | |
87 | dp = VTODE(vdp); | |
88 | pmp = dp->de_pmp; | |
89 | lockparent = ndp->ni_nameiop & LOCKPARENT; | |
90 | flag = ndp->ni_nameiop & OPMASK; | |
91 | wantparent = ndp->ni_nameiop & (LOCKPARENT | WANTPARENT); | |
92 | #if defined(PCFSDEBUG) | |
93 | printf("pcfs_lookup(): vdp %08x, dp %08x, Attr %02x\n", | |
94 | vdp, dp, dp->de_Attributes); | |
95 | #endif /* defined(PCFSDEBUG) */ | |
96 | ||
97 | /* | |
98 | * Be sure vdp is a directory. Since dos filesystems | |
99 | * don't have the concept of execute permission anybody | |
100 | * can search a directory. | |
101 | */ | |
102 | if ((dp->de_Attributes & ATTR_DIRECTORY) == 0) | |
103 | return ENOTDIR; | |
104 | ||
105 | /* | |
106 | * See if the component of the pathname we are looking for | |
107 | * is in the directory cache. If so then do a few things | |
108 | * and return. | |
109 | */ | |
110 | if (error = cache_lookup(ndp)) { | |
111 | int vpid; | |
112 | ||
113 | if (error == ENOENT) | |
114 | return error; | |
115 | #ifdef PARANOID | |
fbebbc5a | 116 | if (vdp == ndp->ni_rootdir && ndp->ni_isdotdot) |
15637ed4 RG |
117 | panic("pcfs_lookup: .. thru root"); |
118 | #endif /* PARANOID */ | |
119 | pdp = dp; | |
120 | vdp = ndp->ni_vp; | |
121 | dp = VTODE(vdp); | |
122 | vpid = vdp->v_id; | |
123 | if (pdp == dp) { | |
124 | VREF(vdp); | |
125 | error = 0; | |
126 | } else if (ndp->ni_isdotdot) { | |
127 | DEUNLOCK(pdp); | |
128 | error = vget(vdp); | |
129 | if (!error && lockparent && *ndp->ni_next == '\0') | |
130 | DELOCK(pdp); | |
131 | } else { | |
132 | error = vget(vdp); | |
133 | if (!lockparent || error || *ndp->ni_next != '\0') | |
134 | DEUNLOCK(pdp); | |
135 | } | |
136 | ||
137 | if (!error) { | |
138 | if (vpid == vdp->v_id) { | |
139 | #if defined(PCFSDEBUG) | |
140 | printf("pcfs_lookup(): cache hit, vnode %08x, file %s\n", vdp, dp->de_Name); | |
141 | #endif /* defined(PCFSDEBUG) */ | |
142 | return 0; | |
143 | } | |
144 | deput(dp); | |
145 | if (lockparent && pdp != dp && *ndp->ni_next == '\0') | |
146 | DEUNLOCK(pdp); | |
147 | } | |
148 | DELOCK(pdp); | |
149 | dp = pdp; | |
150 | vdp = DETOV(dp); | |
151 | ndp->ni_vp = NULL; | |
152 | } | |
153 | ||
154 | /* | |
155 | * If they are going after the . or .. entry in the | |
156 | * root directory, they won't find it. DOS filesystems | |
157 | * don't have them in the root directory. So, we fake it. | |
158 | * deget() is in on this scam too. | |
159 | */ | |
160 | if ((vdp->v_flag & VROOT) && ndp->ni_ptr[0] == '.' && | |
161 | (ndp->ni_namelen == 1 || | |
162 | (ndp->ni_namelen == 2 && ndp->ni_ptr[1] == '.'))) { | |
163 | isadir = ATTR_DIRECTORY; | |
164 | scn = PCFSROOT; | |
165 | #if defined(PCFSDEBUG) | |
166 | printf("pcfs_lookup(): looking for . or .. in root directory\n"); | |
167 | #endif /* defined(PCFSDEBUG) */ | |
4c45483e | 168 | cluster = PCFSROOT; |
15637ed4 RG |
169 | diroff = PCFSROOT_OFS; |
170 | goto foundroot; | |
171 | } | |
172 | ||
173 | /* | |
174 | * Don't search for free slots unless we are creating | |
175 | * a filename and we are at the end of the pathname. | |
176 | */ | |
177 | slotstatus = FOUND; | |
178 | if ((flag == CREATE || flag == RENAME) && *ndp->ni_next == '\0') { | |
179 | slotstatus = NONE; | |
180 | slotoffset = -1; | |
181 | } | |
182 | ||
183 | unix2dosfn((u_char *)ndp->ni_ptr, dosfilename, ndp->ni_namelen); | |
184 | dosfilename[11] = 0; | |
185 | #if defined(PCFSDEBUG) | |
186 | printf("pcfs_lookup(): dos version of filename %s, length %d\n", | |
187 | dosfilename, ndp->ni_namelen); | |
188 | #endif /* defined(PCFSDEBUG) */ | |
189 | /* | |
190 | * Search the directory pointed at by vdp for the | |
191 | * name pointed at by ndp->ni_ptr. | |
192 | */ | |
193 | tdp = NULL; | |
194 | /* | |
195 | * The outer loop ranges over the clusters that make | |
196 | * up the directory. Note that the root directory is | |
197 | * different from all other directories. It has a | |
198 | * fixed number of blocks that are not part of the | |
199 | * pool of allocatable clusters. So, we treat it a | |
200 | * little differently. | |
201 | * The root directory starts at "cluster" 0. | |
202 | */ | |
203 | rootreloff = 0; | |
204 | for (frcn = 0; ; frcn++) { | |
205 | if (error = pcbmap(dp, frcn, &bn, &cluster)) { | |
206 | if (error == E2BIG) | |
207 | break; | |
208 | return error; | |
209 | } | |
210 | if (error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, NOCRED, &bp)) | |
211 | return error; | |
212 | for (diroff = 0; diroff < pmp->pm_depclust; diroff++) { | |
213 | dep = (struct direntry *)bp->b_un.b_addr + diroff; | |
214 | ||
215 | /* | |
216 | * If the slot is empty and we are still looking for | |
217 | * an empty then remember this one. If the slot is | |
218 | * not empty then check to see if it matches what we | |
219 | * are looking for. If the slot has never been filled | |
220 | * with anything, then the remainder of the directory | |
221 | * has never been used, so there is no point in searching | |
222 | * it. | |
223 | */ | |
224 | if (dep->deName[0] == SLOT_EMPTY || | |
225 | dep->deName[0] == SLOT_DELETED) { | |
226 | if (slotstatus != FOUND) { | |
227 | slotstatus = FOUND; | |
228 | if (cluster == PCFSROOT) | |
229 | slotoffset = rootreloff; | |
230 | else | |
231 | slotoffset = diroff; | |
232 | slotcluster = cluster; | |
233 | } | |
234 | if (dep->deName[0] == SLOT_EMPTY) { | |
235 | brelse(bp); | |
236 | goto notfound; | |
237 | } | |
238 | } else { | |
239 | /* Ignore volume labels (anywhere, not just | |
240 | * the root directory). */ | |
241 | if ((dep->deAttributes & ATTR_VOLUME) == 0 && | |
242 | bcmp(dosfilename, dep->deName, 11) == 0) { | |
243 | #if defined(PCFSDEBUG) | |
244 | printf("pcfs_lookup(): match diroff %d, rootreloff %d\n", diroff, rootreloff); | |
245 | #endif /* defined(PCFSDEBUG) */ | |
246 | /* | |
247 | * Remember where this directory entry came from | |
248 | * for whoever did this lookup. | |
249 | * If this is the root directory we are interested | |
250 | * in the offset relative to the beginning of the | |
251 | * directory (not the beginning of the cluster). | |
252 | */ | |
253 | if (cluster == PCFSROOT) | |
254 | diroff = rootreloff; | |
255 | ndp->ni_pcfs.pcfs_offset = diroff; | |
256 | ndp->ni_pcfs.pcfs_cluster = cluster; | |
257 | goto found; | |
258 | } | |
259 | } | |
260 | rootreloff++; | |
261 | } /* for (diroff = 0; .... */ | |
262 | /* | |
263 | * Release the buffer holding the directory cluster | |
264 | * just searched. | |
265 | */ | |
266 | brelse(bp); | |
267 | } /* for (frcn = 0; ; frcn++) */ | |
268 | notfound:; | |
269 | /* | |
270 | * We hold no disk buffers at this point. | |
271 | */ | |
272 | ||
273 | /* | |
274 | * If we get here we didn't find the entry we were looking | |
275 | * for. But that's ok if we are creating or renaming and | |
276 | * are at the end of the pathname and the directory hasn't | |
277 | * been removed. | |
278 | */ | |
279 | #if defined(PCFSDEBUG) | |
280 | printf("pcfs_lookup(): flag %d, refcnt %d, slotstatus %d\n", | |
281 | flag, dp->de_refcnt, slotstatus); | |
282 | printf(" slotoffset %d, slotcluster %d\n", | |
283 | slotoffset, slotcluster); | |
284 | #endif /* defined(PCFSDEBUG) */ | |
285 | if ((flag == CREATE || flag == RENAME) && | |
286 | *ndp->ni_next == '\0' && dp->de_refcnt != 0) { | |
287 | if (slotstatus == NONE) { | |
288 | ndp->ni_pcfs.pcfs_offset = 0; | |
289 | ndp->ni_pcfs.pcfs_cluster = 0; | |
290 | ndp->ni_pcfs.pcfs_count = 0; | |
291 | } else { | |
292 | #if defined(PCFSDEBUG) | |
293 | printf("pcfs_lookup(): saving empty slot location\n"); | |
294 | #endif /* defined(PCFSDEBUG) */ | |
295 | ndp->ni_pcfs.pcfs_offset = slotoffset; | |
296 | ndp->ni_pcfs.pcfs_cluster = slotcluster; | |
297 | ndp->ni_pcfs.pcfs_count = 1; | |
298 | } | |
8183b32d | 299 | /* dp->de_flag |= DEUPD;*/ /* never update dos directories */ |
15637ed4 RG |
300 | ndp->ni_nameiop |= SAVENAME; |
301 | if (!lockparent) /* leave searched dir locked? */ | |
302 | DEUNLOCK(dp); | |
303 | } | |
304 | /* | |
305 | * Insert name in cache as non-existant if not | |
306 | * trying to create it. | |
307 | */ | |
308 | if (ndp->ni_makeentry && flag != CREATE) | |
309 | cache_enter(ndp); | |
310 | return ENOENT; | |
311 | ||
312 | found:; | |
313 | /* | |
314 | * NOTE: We still have the buffer with matched | |
315 | * directory entry at this point. | |
316 | */ | |
317 | isadir = dep->deAttributes & ATTR_DIRECTORY; | |
318 | scn = dep->deStartCluster; | |
319 | ||
320 | foundroot:; | |
321 | /* | |
322 | * If we entered at foundroot, then we are looking | |
323 | * for the . or .. entry of the filesystems root | |
324 | * directory. isadir and scn were setup before | |
325 | * jumping here. And, bp is null. There is no buf header. | |
326 | */ | |
327 | ||
328 | /* | |
329 | * If deleting and at the end of the path, then | |
330 | * if we matched on "." then don't deget() we would | |
331 | * probably panic(). Otherwise deget() the directory | |
332 | * entry. | |
333 | */ | |
334 | if (flag == DELETE && ndp->ni_next == '\0') { | |
335 | if (dp->de_StartCluster == scn && | |
336 | isadir) { /* "." */ | |
337 | VREF(vdp); | |
338 | ndp->ni_vp = vdp; | |
339 | if (bp) brelse(bp); | |
340 | return 0; | |
341 | } | |
342 | error = deget(pmp, cluster, diroff, dep, &tdp); | |
343 | if (error) { | |
344 | if (bp) brelse(bp); | |
345 | return error; | |
346 | } | |
347 | ndp->ni_vp = DETOV(tdp); | |
348 | if (!lockparent) | |
349 | DEUNLOCK(dp); | |
350 | if (bp) brelse(bp); | |
351 | return 0; | |
352 | } | |
353 | ||
354 | /* | |
355 | * If renaming. | |
356 | */ | |
357 | if (flag == RENAME && wantparent && *ndp->ni_next == '\0') { | |
358 | if (dp->de_StartCluster == scn && | |
359 | isadir) { | |
360 | if (bp) brelse(bp); | |
361 | return EISDIR; | |
362 | } | |
363 | error = deget(pmp, cluster, diroff, dep, &tdp); | |
364 | if (error) { | |
365 | if (bp) brelse(bp); | |
366 | return error; | |
367 | } | |
368 | ndp->ni_vp = DETOV(tdp); | |
369 | ndp->ni_nameiop |= SAVENAME; | |
370 | if (!lockparent) | |
371 | DEUNLOCK(dp); | |
372 | if (bp) brelse(bp); | |
373 | return 0; | |
374 | } | |
375 | ||
376 | /* | |
377 | * ? | |
378 | */ | |
379 | pdp = dp; | |
380 | if (ndp->ni_isdotdot) { | |
381 | DEUNLOCK(pdp); | |
382 | error = deget(pmp, cluster, diroff, dep, &tdp); | |
383 | if (error) { | |
384 | DELOCK(pdp); | |
385 | if (bp) brelse(bp); | |
386 | return error; | |
387 | } | |
388 | if (lockparent && *ndp->ni_next == '\0') | |
389 | DELOCK(pdp); | |
390 | ndp->ni_vp = DETOV(tdp); | |
391 | } else if (dp->de_StartCluster == scn && | |
392 | isadir) { /* "." */ | |
393 | VREF(vdp); | |
394 | ndp->ni_vp = vdp; | |
395 | } else { | |
396 | error = deget(pmp, cluster, diroff, dep, &tdp); | |
397 | if (error) { | |
398 | if (bp) brelse(bp); | |
399 | return error; | |
400 | } | |
401 | if (!lockparent || *ndp->ni_next != '\0') | |
402 | DEUNLOCK(pdp); | |
403 | ndp->ni_vp = DETOV(tdp); | |
404 | } | |
405 | if (bp) brelse(bp); | |
406 | ||
407 | /* | |
408 | * Insert name in cache if wanted. | |
409 | */ | |
410 | if (ndp->ni_makeentry) | |
411 | cache_enter(ndp); | |
412 | return 0; | |
413 | } | |
414 | ||
415 | /* | |
416 | * dep - directory to copy into the directory | |
417 | * ndp - nameidata structure containing info on | |
418 | * where to put the directory entry in the directory. | |
419 | * depp - return the address of the denode for the | |
420 | * created directory entry if depp != 0 | |
421 | */ | |
422 | int | |
423 | createde(dep, ndp, depp) | |
424 | struct denode *dep; | |
425 | struct nameidata *ndp; | |
426 | struct denode **depp; | |
427 | { | |
428 | int bn; | |
429 | int error; | |
fde1aeb2 GW |
430 | u_int dirclust; |
431 | u_long diroffset; | |
15637ed4 RG |
432 | struct direntry *ndep; |
433 | struct denode *ddep = VTODE(ndp->ni_dvp); /* directory to add to */ | |
434 | struct pcfsmount *pmp = dep->de_pmp; | |
435 | struct buf *bp; | |
436 | #if defined(PCFSDEBUG) | |
437 | printf("createde(dep %08x, ndp %08x, depp %08x)\n", dep, ndp, depp); | |
438 | #endif /* defined(PCFSDEBUG) */ | |
439 | ||
440 | /* | |
441 | * If no space left in the directory then allocate | |
442 | * another cluster and chain it onto the end of the | |
443 | * file. There is one exception to this. That is, | |
444 | * if the root directory has no more space it can NOT | |
445 | * be expanded. extendfile() checks for and fails attempts to | |
446 | * extend the root directory. We just return an error | |
447 | * in that case. | |
448 | */ | |
449 | if (ndp->ni_pcfs.pcfs_count == 0) { | |
450 | if (error = extendfile(ddep, &bp, &dirclust)) | |
451 | return error; | |
452 | ndep = (struct direntry *)bp->b_un.b_addr; | |
453 | /* | |
454 | * Let caller know where we put the directory entry. | |
455 | */ | |
456 | ndp->ni_pcfs.pcfs_cluster = dirclust; | |
457 | ndp->ni_pcfs.pcfs_offset = diroffset = 0; | |
458 | } | |
459 | ||
460 | else { | |
461 | /* | |
462 | * There is space in the existing directory. So, | |
463 | * we just read in the cluster with space. Copy | |
464 | * the new directory entry in. Then write it to | |
465 | * disk. | |
466 | * NOTE: DOS directories do not get smaller as | |
467 | * clusters are emptied. | |
468 | */ | |
469 | dirclust = ndp->ni_pcfs.pcfs_cluster; | |
470 | diroffset = ndp->ni_pcfs.pcfs_offset; | |
471 | ||
472 | error = readep(pmp, dirclust, diroffset, &bp, &ndep); | |
473 | if (error) | |
474 | return error; | |
475 | } | |
476 | *ndep = dep->de_de; | |
477 | /* | |
478 | * If they want us to return with the denode gotten. | |
479 | */ | |
480 | if (depp) { | |
481 | error = deget(pmp, dirclust, diroffset, ndep, depp); | |
482 | if (error) | |
483 | return error; | |
484 | } | |
485 | if (error = bwrite(bp)) | |
486 | /*deput()?*/ | |
487 | return error; | |
488 | return 0; | |
489 | } | |
490 | ||
491 | /* | |
492 | * Read in a directory entry and mark it as being deleted. | |
493 | */ | |
494 | int | |
495 | markdeleted(pmp, dirclust, diroffset) | |
496 | struct pcfsmount *pmp; | |
497 | u_long dirclust; | |
498 | u_long diroffset; | |
499 | { | |
500 | int error; | |
501 | struct direntry *ep; | |
502 | struct buf *bp; | |
503 | ||
504 | error = readep(pmp, dirclust, diroffset, &bp, &ep); | |
505 | if (error) | |
506 | return error; | |
507 | ep->deName[0] = SLOT_DELETED; | |
508 | return bwrite(bp); | |
509 | } | |
510 | ||
511 | /* | |
512 | * Remove a directory entry. | |
513 | * At this point the file represented by the directory | |
514 | * entry to be removed is still full length until no | |
515 | * one has it open. When the file no longer being | |
516 | * used pcfs_inactive() is called and will truncate | |
517 | * the file to 0 length. When the vnode containing | |
518 | * the denode is needed for some other purpose by | |
519 | * VFS it will call pcfs_reclaim() which will remove | |
520 | * the denode from the denode cache. | |
521 | */ | |
522 | int | |
523 | removede(ndp) | |
524 | struct nameidata *ndp; | |
525 | { | |
526 | struct denode *dep = VTODE(ndp->ni_vp); /* the file being removed */ | |
527 | struct pcfsmount *pmp = dep->de_pmp; | |
528 | int error; | |
529 | ||
530 | #if defined(PCFSDEBUG) | |
531 | /*printf("removede(): filename %s\n", dep->de_Name); | |
532 | printf("rmde(): dep %08x, ndpcluster %d, ndpoffset %d\n", | |
533 | dep, ndp->ni_pcfs.pcfs_cluster, ndp->ni_pcfs.pcfs_offset);*/ | |
534 | #endif /* defined(PCFSDEBUG) */ | |
535 | ||
536 | /* | |
537 | * Read the directory block containing the directory | |
538 | * entry we are to make free. The nameidata structure | |
539 | * holds the cluster number and directory entry index | |
540 | * number of the entry to free. | |
541 | */ | |
542 | error = markdeleted(pmp, ndp->ni_pcfs.pcfs_cluster, | |
543 | ndp->ni_pcfs.pcfs_offset); | |
544 | ||
545 | dep->de_refcnt--; | |
546 | return error; | |
547 | } | |
548 | ||
549 | /* | |
550 | * Be sure a directory is empty except for "." and "..". | |
551 | * Return 1 if empty, return 0 if not empty or error. | |
552 | */ | |
553 | int | |
554 | dosdirempty(dep) | |
555 | struct denode *dep; | |
556 | { | |
557 | int dei; | |
558 | int error; | |
559 | u_long cn; | |
560 | daddr_t bn; | |
561 | struct buf *bp; | |
562 | struct pcfsmount *pmp = dep->de_pmp; | |
563 | struct direntry *dentp; | |
564 | ||
565 | /* | |
566 | * Since the filesize field in directory entries for a directory | |
567 | * is zero, we just have to feel our way through the directory | |
568 | * until we hit end of file. | |
569 | */ | |
570 | for (cn = 0;; cn++) { | |
571 | error = pcbmap(dep, cn, &bn, 0); | |
572 | if (error == E2BIG) | |
573 | return 1; /* it's empty */ | |
574 | error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, NOCRED, | |
575 | &bp); | |
576 | if (error) | |
577 | return error; | |
578 | dentp = (struct direntry *)bp->b_un.b_addr; | |
579 | for (dei = 0; dei < pmp->pm_depclust; dei++) { | |
580 | if (dentp->deName[0] != SLOT_DELETED) { | |
581 | /* | |
582 | * In dos directories an entry whose name starts with SLOT_EMPTY (0) | |
583 | * starts the beginning of the unused part of the directory, so we | |
584 | * can just return that it is empty. | |
585 | */ | |
586 | if (dentp->deName[0] == SLOT_EMPTY) { | |
587 | brelse(bp); | |
588 | return 1; | |
589 | } | |
590 | /* | |
591 | * Any names other than "." and ".." in a directory mean | |
592 | * it is not empty. | |
593 | */ | |
594 | if (bcmp(dentp->deName, ". ", 11) && | |
595 | bcmp(dentp->deName, ".. ", 11)) { | |
596 | brelse(bp); | |
597 | #if defined(PCFSDEBUG) | |
598 | printf("dosdirempty(): entry %d found %02x, %02x\n", dei, dentp->deName[0], | |
599 | dentp->deName[1]); | |
600 | #endif /* defined(PCFSDEBUG) */ | |
601 | return 0; /* not empty */ | |
602 | } | |
603 | } | |
604 | dentp++; | |
605 | } | |
606 | brelse(bp); | |
607 | } | |
608 | /*NOTREACHED*/ | |
609 | } | |
610 | ||
611 | /* | |
612 | * Check to see if the directory described by target is | |
613 | * in some subdirectory of source. This prevents something | |
614 | * like the following from succeeding and leaving a bunch | |
615 | * or files and directories orphaned. | |
616 | * mv /a/b/c /a/b/c/d/e/f | |
617 | * Where c and f are directories. | |
618 | * source - the inode for /a/b/c | |
619 | * target - the inode for /a/b/c/d/e/f | |
620 | * Returns 0 if target is NOT a subdirectory of source. | |
621 | * Otherwise returns a non-zero error number. | |
622 | * The target inode is always unlocked on return. | |
623 | */ | |
624 | int | |
625 | doscheckpath(source, target) | |
626 | struct denode *source; | |
627 | struct denode *target; | |
628 | { | |
629 | daddr_t scn; | |
630 | struct denode dummy; | |
631 | struct pcfsmount *pmp; | |
632 | struct direntry *ep; | |
633 | struct denode *dep; | |
634 | struct buf *bp = NULL; | |
635 | int error = 0; | |
636 | ||
637 | dep = target; | |
638 | if ((target->de_Attributes & ATTR_DIRECTORY) == 0 || | |
639 | (source->de_Attributes & ATTR_DIRECTORY) == 0) { | |
640 | error = ENOTDIR; | |
641 | goto out; | |
642 | } | |
643 | if (dep->de_StartCluster == source->de_StartCluster) { | |
644 | error = EEXIST; | |
645 | goto out; | |
646 | } | |
647 | if (dep->de_StartCluster == PCFSROOT) | |
648 | goto out; | |
649 | for (;;) { | |
650 | if ((dep->de_Attributes & ATTR_DIRECTORY) == 0) { | |
651 | error = ENOTDIR; | |
652 | goto out; | |
653 | } | |
654 | pmp = dep->de_pmp; | |
655 | scn = dep->de_StartCluster; | |
656 | error = bread(pmp->pm_devvp, cntobn(pmp, scn), | |
657 | pmp->pm_bpcluster, NOCRED, &bp); | |
658 | if (error) { | |
659 | break; | |
660 | } | |
661 | ep = (struct direntry *)bp->b_un.b_addr + 1; | |
662 | if ((ep->deAttributes & ATTR_DIRECTORY) == 0 || | |
663 | bcmp(ep->deName, ".. ", 11) != 0) { | |
664 | error = ENOTDIR; | |
665 | break; | |
666 | } | |
667 | if (ep->deStartCluster == source->de_StartCluster) { | |
668 | error = EINVAL; | |
669 | break; | |
670 | } | |
671 | if (ep->deStartCluster == PCFSROOT) | |
672 | break; | |
673 | deput(dep); | |
674 | /* NOTE: deget() clears dep on error */ | |
675 | error = deget(pmp, ep->deStartCluster, 0, ep, &dep); | |
676 | brelse(bp); | |
677 | bp = NULL; | |
678 | if (error) | |
679 | break; | |
680 | } | |
681 | out:; | |
682 | if (bp) | |
683 | brelse(bp); | |
684 | if (error == ENOTDIR) | |
685 | printf("doscheckpath(): .. not a directory?\n"); | |
686 | if (dep != NULL) | |
687 | deput(dep); | |
688 | return error; | |
689 | } | |
690 | ||
691 | /* | |
692 | * Read in the disk block containing the directory entry | |
693 | * (dirclu, dirofs) and return the address of the buf header, | |
694 | * and the address of the directory entry within the block. | |
695 | */ | |
696 | int | |
697 | readep(pmp, dirclu, dirofs, bpp, epp) | |
698 | struct pcfsmount *pmp; | |
699 | u_long dirclu, dirofs; | |
700 | struct buf **bpp; | |
701 | struct direntry **epp; | |
702 | { | |
703 | int error; | |
704 | daddr_t bn; | |
705 | ||
706 | bn = detobn(pmp, dirclu, dirofs); | |
707 | if (error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, NOCRED, bpp)) { | |
708 | *bpp = NULL; | |
709 | return error; | |
710 | } | |
711 | if (epp) | |
712 | *epp = bptoep(pmp, *bpp, dirofs); | |
713 | return 0; | |
714 | } | |
715 | ||
716 | ||
717 | /* | |
718 | * Read in the disk block containing the directory entry | |
719 | * dep came from and return the address of the buf header, | |
720 | * and the address of the directory entry within the block. | |
721 | */ | |
722 | int | |
723 | readde(dep, bpp, epp) | |
724 | struct denode *dep; | |
725 | struct buf **bpp; | |
726 | struct direntry **epp; | |
727 | { | |
728 | return readep(dep->de_pmp, dep->de_dirclust, dep->de_diroffset, | |
729 | bpp, epp); | |
730 | } |