Commit | Line | Data |
---|---|---|
a6b6f679 | 1 | /* ufs_lookup.c 4.22 82/08/14 */ |
10873320 BJ |
2 | |
3 | #include "../h/param.h" | |
4 | #include "../h/systm.h" | |
5 | #include "../h/inode.h" | |
6459ebe0 | 6 | #include "../h/fs.h" |
10873320 BJ |
7 | #include "../h/mount.h" |
8 | #include "../h/dir.h" | |
9 | #include "../h/user.h" | |
10 | #include "../h/buf.h" | |
3cbbbe12 | 11 | #include "../h/conf.h" |
10873320 | 12 | |
4a0415d6 | 13 | struct buf *blkatoff(); |
6bd0bb92 | 14 | int dirchk = 1; |
10873320 | 15 | /* |
6bd0bb92 BJ |
16 | * Convert a pathname into a pointer to a locked inode, |
17 | * with side effects usable in creating and removing files. | |
18 | * This is a very central and rather complicated routine. | |
19 | * | |
20 | * The func argument gives the routine which returns successive | |
21 | * characters of the name to be translated. The flag | |
22 | * argument is (0, 1, 2) depending on whether the name is to be | |
23 | * (looked up, created, deleted). The follow argument is 1 when | |
24 | * symbolic links are to be followed when they occur at the end of | |
25 | * the name translation process. | |
10873320 | 26 | * |
6bd0bb92 BJ |
27 | * Overall outline: |
28 | * | |
29 | * copy in name | |
30 | * get starting directory | |
31 | * dirloop: | |
32 | * check accessibility of directory | |
33 | * dirloop2: | |
34 | * copy next component of name to u.u_dent | |
35 | * handle degenerate case where name is null string | |
36 | * search for name in directory, to found or notfound | |
37 | * notfound: | |
38 | * if creating, return locked inode, leaving information on avail. slots | |
39 | * else return error | |
40 | * found: | |
41 | * if at end of path and deleting, return information to allow delete | |
42 | * if .. and on mounted filesys, look in mount table for parent | |
43 | * if symbolic link, massage name in buffer and continue at dirloop | |
44 | * if more components of name, do next level at dirloop | |
45 | * return the answer as locked inode | |
10873320 BJ |
46 | */ |
47 | struct inode * | |
f5039631 BJ |
48 | namei(func, flag, follow) |
49 | int (*func)(), flag, follow; | |
10873320 | 50 | { |
6bd0bb92 BJ |
51 | register char *cp; /* pointer into pathname argument */ |
52 | /* these variables refer to things which must be freed or unlocked */ | |
53 | register struct inode *dp = 0; /* the directory we are searching */ | |
54 | register struct fs *fs; /* file system that directory is in */ | |
55 | register struct buf *bp = 0; /* a buffer of directory entries */ | |
56 | register struct direct *ep; /* the current directory entry */ | |
57 | int entryoffsetinblock; /* offset of ep in bp's buffer */ | |
58 | register struct buf *nbp; /* buffer storing path name argument */ | |
59 | /* these variables hold information about the search for a slot */ | |
60 | enum {NONE, COMPACT, FOUND} slotstatus; | |
61 | int slotoffset = -1; /* offset of area with free space */ | |
62 | int slotsize; /* size of area at slotoffset */ | |
63 | int slotfreespace; /* amount of space free in slot */ | |
64 | int slotneeded; /* size of the entry we're seeking */ | |
65 | /* */ | |
66 | int dirsize; | |
67 | int prevoff; /* u.u_offset of previous entry */ | |
68 | int nlink = 0; /* number of symbolic links taken */ | |
69 | struct inode *pdp; /* saved dp during symlink work */ | |
70 | int i; | |
10873320 | 71 | |
f5039631 | 72 | /* |
6bd0bb92 BJ |
73 | * Get a buffer for the name to be translated, and copy the |
74 | * name into the buffer. | |
f5039631 | 75 | */ |
6459ebe0 | 76 | nbp = geteblk(MAXPATHLEN); |
6bd0bb92 BJ |
77 | for (cp = nbp->b_un.b_addr; *cp = (*func)(); ) { |
78 | if ((*cp&0377) == ('/'|0200) || (*cp&0200) && flag != 2) { | |
a21ae242 | 79 | u.u_error = EPERM; |
6bd0bb92 | 80 | goto bad; |
a21ae242 | 81 | } |
a21ae242 | 82 | cp++; |
6459ebe0 | 83 | if (cp >= nbp->b_un.b_addr + MAXPATHLEN) { |
f5039631 | 84 | u.u_error = ENOENT; |
6bd0bb92 | 85 | goto bad; |
f5039631 BJ |
86 | } |
87 | } | |
6bd0bb92 BJ |
88 | if (u.u_error) |
89 | goto bad; | |
90 | ||
10873320 | 91 | /* |
6bd0bb92 | 92 | * Get starting directory. |
10873320 | 93 | */ |
6bd0bb92 | 94 | cp = nbp->b_un.b_addr; |
f5039631 BJ |
95 | if (*cp == '/') { |
96 | while (*cp == '/') | |
97 | cp++; | |
10873320 BJ |
98 | if ((dp = u.u_rdir) == NULL) |
99 | dp = rootdir; | |
6bd0bb92 BJ |
100 | } else |
101 | dp = u.u_cdir; | |
102 | fs = dp->i_fs; | |
f5039631 BJ |
103 | ilock(dp); |
104 | dp->i_count++; | |
6bd0bb92 BJ |
105 | u.u_pdir = (struct inode *)0xc0000000; /* illegal */ |
106 | ||
10873320 | 107 | /* |
6bd0bb92 BJ |
108 | * We come to dirloop to search a new directory. |
109 | * The directory must be locked so that it can be | |
110 | * iput, and fs must be already set to dp->i_fs. | |
10873320 | 111 | */ |
6bd0bb92 | 112 | dirloop: |
a0aead5a | 113 | /* |
6bd0bb92 | 114 | * Check accessiblity of directory. |
a0aead5a | 115 | */ |
6bd0bb92 | 116 | if ((dp->i_mode&IFMT) != IFDIR) { |
10873320 | 117 | u.u_error = ENOTDIR; |
6bd0bb92 BJ |
118 | goto bad; |
119 | } | |
120 | if (access(dp, IEXEC)) | |
121 | goto bad; | |
122 | ||
6f004ab5 | 123 | dirloop2: |
6bd0bb92 BJ |
124 | /* |
125 | * Copy next component of name to u.u_dent. | |
126 | */ | |
127 | for (i = 0; *cp != 0 && *cp != '/'; cp++) { | |
6459ebe0 | 128 | if (i >= MAXNAMLEN) { |
f5039631 | 129 | u.u_error = ENOENT; |
6bd0bb92 | 130 | goto bad; |
6459ebe0 | 131 | } |
6bd0bb92 | 132 | u.u_dent.d_name[i++] = *cp; |
6459ebe0 KM |
133 | } |
134 | u.u_dent.d_namlen = i; | |
6bd0bb92 BJ |
135 | u.u_dent.d_name[i] = 0; |
136 | ||
137 | /* | |
138 | * Check for degenerate name (e.g. / or "") | |
139 | * which is a way of talking about a directory, | |
140 | * e.g. like "/." or ".". | |
141 | */ | |
142 | if (u.u_dent.d_name[0] == 0) { | |
143 | if (flag) { | |
f5039631 | 144 | u.u_error = ENOENT; |
6bd0bb92 | 145 | goto bad; |
f5039631 | 146 | } |
6459ebe0 KM |
147 | brelse(nbp); |
148 | return (dp); | |
f5039631 | 149 | } |
6bd0bb92 | 150 | |
6459ebe0 | 151 | /* |
6bd0bb92 BJ |
152 | * Suppress search for slots unless creating |
153 | * file and at end of pathname, in which case | |
154 | * we watch for a place to put the new file in | |
155 | * case it doesn't already exist. | |
6459ebe0 | 156 | */ |
6bd0bb92 BJ |
157 | slotstatus = FOUND; |
158 | if (flag == 1 && *cp == 0) { | |
159 | slotstatus = NONE; | |
160 | slotfreespace = 0; | |
161 | slotneeded = DIRSIZ(&u.u_dent); | |
162 | } | |
163 | ||
164 | dirsize = roundup(dp->i_size, DIRBLKSIZ); | |
6459ebe0 | 165 | u.u_offset = 0; |
6bd0bb92 | 166 | while (u.u_offset < dirsize) { |
f5039631 BJ |
167 | /* |
168 | * If offset is on a block boundary, | |
169 | * read the next directory block. | |
170 | * Release previous if it exists. | |
171 | */ | |
6459ebe0 | 172 | if (blkoff(fs, u.u_offset) == 0) { |
f5039631 BJ |
173 | if (bp != NULL) |
174 | brelse(bp); | |
4a0415d6 | 175 | bp = blkatoff(dp, u.u_offset, (char **)0); |
6bd0bb92 BJ |
176 | if (bp == 0) |
177 | goto bad; | |
178 | entryoffsetinblock = 0; | |
6459ebe0 | 179 | } |
6bd0bb92 | 180 | |
6459ebe0 | 181 | /* |
6bd0bb92 BJ |
182 | * If still looking for a slot, and at a DIRBLKSIZE |
183 | * boundary, have to start looking for free space | |
184 | * again. | |
6459ebe0 | 185 | */ |
6bd0bb92 BJ |
186 | if (slotstatus == NONE && |
187 | (entryoffsetinblock&(DIRBLKSIZ-1)) == 0) { | |
188 | slotoffset = -1; | |
189 | slotfreespace = 0; | |
190 | } | |
191 | ||
192 | /* | |
193 | * Get pointer to next entry, and do consistency checking: | |
194 | * record length must be multiple of 4 | |
4a0415d6 | 195 | * record length must not be zero |
6bd0bb92 BJ |
196 | * entry must fit in rest of this DIRBLKSIZ block |
197 | * record must be large enough to contain name | |
4a0415d6 SL |
198 | * When dirchk is set we also check: |
199 | * name is not longer than MAXNAMLEN | |
6bd0bb92 | 200 | * name must be as long as advertised, and null terminated |
4a0415d6 SL |
201 | * Checking last two conditions is done only when dirchk is |
202 | * set, to save time. | |
6bd0bb92 BJ |
203 | */ |
204 | ep = (struct direct *)(bp->b_un.b_addr + entryoffsetinblock); | |
205 | i = DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1)); | |
4a0415d6 SL |
206 | if ((ep->d_reclen & 0x3) || ep->d_reclen == 0 || |
207 | ep->d_reclen > i || DIRSIZ(ep) > ep->d_reclen || | |
208 | dirchk && (ep->d_namlen > MAXNAMLEN || dirbadname(ep))) { | |
6bd0bb92 | 209 | dirbad(dp, "mangled entry"); |
6459ebe0 | 210 | u.u_offset += i; |
6bd0bb92 | 211 | entryoffsetinblock += i; |
6459ebe0 KM |
212 | continue; |
213 | } | |
6bd0bb92 | 214 | |
6459ebe0 | 215 | /* |
6bd0bb92 | 216 | * If an appropriate sized slot has not yet been found, |
6459ebe0 KM |
217 | * check to see if one is available. Also accumulate space |
218 | * in the current block so that we can determine if | |
219 | * compaction is viable. | |
220 | */ | |
6bd0bb92 BJ |
221 | if (slotstatus != FOUND) { |
222 | int size = ep->d_reclen; | |
223 | ||
6459ebe0 KM |
224 | if (ep->d_ino != 0) |
225 | size -= DIRSIZ(ep); | |
226 | if (size > 0) { | |
6bd0bb92 BJ |
227 | if (size >= slotneeded) { |
228 | slotstatus = FOUND; | |
229 | slotoffset = u.u_offset; | |
230 | slotsize = ep->d_reclen; | |
231 | } else if (slotstatus == NONE) { | |
232 | slotfreespace += size; | |
233 | if (slotoffset == -1) | |
234 | slotoffset = u.u_offset; | |
235 | if (slotfreespace >= slotneeded) { | |
236 | slotstatus = COMPACT; | |
237 | slotsize = | |
238 | u.u_offset+ep->d_reclen - | |
239 | slotoffset; | |
240 | } | |
6459ebe0 | 241 | } |
f5039631 | 242 | } |
f5039631 | 243 | } |
6bd0bb92 | 244 | |
f5039631 | 245 | /* |
6bd0bb92 | 246 | * Check for a name match. |
f5039631 | 247 | */ |
6bd0bb92 BJ |
248 | if (ep->d_ino) { |
249 | if (ep->d_namlen == u.u_dent.d_namlen && | |
250 | !bcmp(u.u_dent.d_name, ep->d_name, ep->d_namlen)) | |
251 | goto found; | |
252 | } | |
253 | prevoff = u.u_offset; | |
6459ebe0 | 254 | u.u_offset += ep->d_reclen; |
6bd0bb92 BJ |
255 | entryoffsetinblock += ep->d_reclen; |
256 | } | |
257 | /* notfound: */ | |
258 | /* | |
259 | * If creating, and at end of pathname and current | |
260 | * directory has not been removed, then can consider allowing | |
261 | * file to be created. | |
262 | */ | |
263 | if (flag == 1 && *cp == 0 && dp->i_nlink != 0) { | |
f5039631 | 264 | /* |
6bd0bb92 BJ |
265 | * Access for write is interpreted as allowing |
266 | * creation of files in the directory. | |
f5039631 | 267 | */ |
6bd0bb92 BJ |
268 | if (access(dp, IWRITE)) |
269 | goto bad; | |
f5039631 | 270 | /* |
6bd0bb92 BJ |
271 | * Return an indication of where the new directory |
272 | * entry should be put. If we didn't find a slot, | |
273 | * then set u.u_count to 0 indicating that the | |
274 | * new slot belongs at the end of the directory. | |
275 | * If we found a slot, then the new entry can be | |
276 | * put in the range [u.u_offset..u.u_offset+u.u_count) | |
f5039631 | 277 | */ |
6bd0bb92 BJ |
278 | if (slotstatus == NONE) |
279 | u.u_count = 0; | |
280 | else { | |
281 | u.u_offset = slotoffset; | |
282 | u.u_count = slotsize; | |
5485e062 | 283 | } |
6bd0bb92 BJ |
284 | dp->i_flag |= IUPD|ICHG; |
285 | if (bp) | |
286 | brelse(bp); | |
287 | brelse(nbp); | |
f5039631 | 288 | /* |
6bd0bb92 BJ |
289 | * We return with the directory locked, so that |
290 | * the parameters we set up above will still be | |
291 | * valid if we actually decide to do a direnter(). | |
292 | * We return NULL to indicate that the entry doesn't | |
293 | * currently exist, leaving a pointer to the (locked) | |
294 | * directory inode in u.u_pdir. | |
f5039631 | 295 | */ |
6bd0bb92 BJ |
296 | u.u_pdir = dp; |
297 | return (NULL); | |
298 | } | |
299 | u.u_error = ENOENT; | |
300 | goto bad; | |
301 | found: | |
302 | /* | |
303 | * Check that directory length properly reflects presence | |
304 | * of this entry. | |
305 | */ | |
4a0415d6 | 306 | if (entryoffsetinblock + DIRSIZ(ep) > dp->i_size) { |
6bd0bb92 | 307 | dirbad(dp, "i_size too small"); |
4a0415d6 | 308 | dp->i_size = entryoffsetinblock + DIRSIZ(ep); |
6bd0bb92 BJ |
309 | dp->i_flag |= IUPD|ICHG; |
310 | } | |
311 | ||
312 | /* | |
313 | * Found component in pathname; save directory | |
314 | * entry in u.u_dent, and release directory buffer. | |
315 | */ | |
316 | bcopy((caddr_t)ep, (caddr_t)&u.u_dent, DIRSIZ(ep)); | |
317 | brelse(bp); | |
318 | bp = NULL; | |
319 | ||
320 | /* | |
321 | * If deleting, and at end of pathname, return | |
322 | * parameters which can be used to remove file. | |
323 | * Note that in this case we return the directory | |
324 | * inode, not the inode of the file being deleted. | |
325 | */ | |
326 | if (flag == 2 && *cp == 0) { | |
327 | /* | |
328 | * Write access to directory required to delete files. | |
329 | */ | |
330 | if (access(dp, IWRITE)) | |
331 | goto bad; | |
332 | /* | |
333 | * Return pointer to current entry in u.u_offset, | |
334 | * and distance past previous entry (if there | |
335 | * is a previous entry in this block) in u.u_count. | |
336 | * Save directory inode pointer in u.u_pdir for dirremove(). | |
337 | */ | |
338 | if ((u.u_offset&(DIRBLKSIZ-1)) == 0) | |
339 | u.u_count = 0; | |
340 | else | |
341 | u.u_count = u.u_offset - prevoff; | |
342 | brelse(nbp); | |
343 | u.u_pdir = dp; /* for dirremove() */ | |
344 | return (dp); | |
345 | } | |
346 | ||
347 | /* | |
348 | * Special handling for ".." allowing chdir out of mounted | |
349 | * file system: indirect .. in root inode to reevaluate | |
350 | * in directory file system was mounted on. | |
351 | */ | |
352 | if (u.u_dent.d_name[0] == '.' && u.u_dent.d_name[1] == '.' && | |
353 | u.u_dent.d_name[2] == '\0') { | |
354 | if (dp == u.u_rdir) | |
355 | u.u_dent.d_ino = dp->i_number; | |
356 | else if (u.u_dent.d_ino == ROOTINO && | |
357 | dp->i_number == ROOTINO) { | |
358 | for (i = 1; i < NMOUNT; i++) | |
359 | if (mount[i].m_bufp != NULL && | |
360 | mount[i].m_dev == dp->i_dev) { | |
6459ebe0 | 361 | iput(dp); |
6bd0bb92 | 362 | dp = mount[i].m_inodp; |
f5039631 BJ |
363 | ilock(dp); |
364 | dp->i_count++; | |
6bd0bb92 BJ |
365 | fs = dp->i_fs; |
366 | cp -= 2; /* back over .. */ | |
367 | goto dirloop2; | |
f5039631 | 368 | } |
10873320 | 369 | } |
6bd0bb92 BJ |
370 | } |
371 | ||
372 | /* | |
373 | * Check for symbolic link, which may require us | |
374 | * to massage the name before we continue translation. | |
375 | * To avoid deadlock have to unlock the current directory, | |
376 | * but don't iput it because we may need it again (if | |
377 | * the symbolic link is relative to .). Instead save | |
378 | * it (unlocked) as pdp. | |
379 | */ | |
380 | pdp = dp; | |
381 | iunlock(pdp); | |
382 | dp = iget(dp->i_dev, fs, u.u_dent.d_ino); | |
383 | if (dp == NULL) | |
384 | goto bad2; | |
385 | fs = dp->i_fs; | |
386 | ||
387 | /* | |
388 | * Check for symbolic link | |
389 | */ | |
390 | if ((dp->i_mode & IFMT) == IFLNK && (follow || *cp == '/')) { | |
391 | int pathlen = strlen(cp) + 1; | |
392 | int bn; | |
393 | ||
394 | if (dp->i_size + pathlen >= MAXPATHLEN - 1 || | |
395 | ++nlink > MAXSYMLINKS) { | |
396 | u.u_error = ELOOP; | |
397 | goto bad2; | |
398 | } | |
399 | bcopy(cp, nbp->b_un.b_addr + dp->i_size, pathlen); | |
a6b6f679 BJ |
400 | u.u_error = |
401 | readip1(dp, nbp->b_un.b_addr, dp->i_size, 0, 1, 0); | |
6bd0bb92 BJ |
402 | if (u.u_error) |
403 | goto bad2; | |
404 | cp = nbp->b_un.b_addr; | |
405 | iput(dp); | |
f5039631 | 406 | if (*cp == '/') { |
6bd0bb92 | 407 | irele(pdp); |
f5039631 BJ |
408 | while (*cp == '/') |
409 | cp++; | |
6bd0bb92 BJ |
410 | if ((dp = u.u_rdir) == NULL) |
411 | dp = rootdir; | |
412 | ilock(dp); | |
413 | dp->i_count++; | |
414 | } else { | |
415 | dp = pdp; | |
416 | ilock(dp); | |
f5039631 | 417 | } |
6bd0bb92 BJ |
418 | fs = dp->i_fs; |
419 | goto dirloop; | |
10873320 | 420 | } |
6bd0bb92 BJ |
421 | irele(pdp); |
422 | ||
10873320 | 423 | /* |
6bd0bb92 BJ |
424 | * Not a symbolic link. If more pathname, |
425 | * continue at next component, else return. | |
10873320 | 426 | */ |
6bd0bb92 BJ |
427 | if (*cp == '/') { |
428 | while (*cp == '/') | |
429 | cp++; | |
430 | goto dirloop; | |
10873320 | 431 | } |
6bd0bb92 BJ |
432 | brelse(nbp); |
433 | return (dp); | |
434 | bad2: | |
435 | irele(pdp); | |
436 | bad: | |
437 | if (bp) | |
438 | brelse(bp); | |
439 | if (dp) | |
440 | iput(dp); | |
f5039631 | 441 | brelse(nbp); |
6459ebe0 | 442 | return (NULL); |
10873320 BJ |
443 | } |
444 | ||
6bd0bb92 BJ |
445 | dirbad(ip, how) |
446 | struct inode *ip; | |
447 | char *how; | |
448 | { | |
449 | ||
450 | printf("%s: bad dir ino %d at offset %d: %s\n", | |
451 | ip->i_fs->fs_fsmnt, ip->i_number, u.u_offset, how); | |
452 | } | |
453 | ||
454 | dirbadname(ep) | |
455 | register struct direct *ep; | |
456 | { | |
457 | register char *cp; | |
458 | register int i; | |
459 | ||
460 | for (i = 0; i < ep->d_namlen; i++) | |
461 | if (ep->d_name[i] == 0) | |
462 | return (1); | |
463 | return (ep->d_name[i]); | |
464 | } | |
465 | ||
6bd0bb92 BJ |
466 | /* |
467 | * Write a directory entry after a call to namei, using the parameters | |
468 | * which it left in the u. area. The argument ip is the inode which | |
469 | * the new directory entry will refer to. The u. area field u.u_pdir is | |
470 | * a pointer to the directory to be written, which was left locked by | |
471 | * namei. Remaining parameters (u.u_offset, u.u_count) indicate | |
472 | * how the space for the new entry is to be gotten. | |
473 | */ | |
474 | direnter(ip) | |
475 | struct inode *ip; | |
f5039631 | 476 | { |
6bd0bb92 BJ |
477 | register struct direct *ep, *nep; |
478 | struct fs *fs; | |
479 | struct buf *bp; | |
480 | int loc, dsize, freespace, newentrysize; | |
481 | char *dirbuf; | |
f5039631 | 482 | |
6bd0bb92 BJ |
483 | u.u_dent.d_ino = ip->i_number; |
484 | u.u_segflg = 1; | |
485 | newentrysize = DIRSIZ(&u.u_dent); | |
486 | if (u.u_count == 0) { | |
487 | /* | |
488 | * If u.u_count is 0, then namei could find no space in the | |
489 | * directory. In this case u.u_offset will be on a directory | |
490 | * block boundary and we will write the new entry into a fresh | |
491 | * block. | |
492 | */ | |
493 | if (u.u_offset&(DIRBLKSIZ-1)) | |
494 | panic("wdir: newblk"); | |
495 | u.u_dent.d_reclen = DIRBLKSIZ; | |
496 | u.u_count = newentrysize; | |
497 | u.u_base = (caddr_t)&u.u_dent; | |
498 | u.u_segflg = 1; | |
499 | writei(u.u_pdir); | |
500 | iput(u.u_pdir); | |
501 | return; | |
502 | } | |
503 | ||
504 | /* | |
505 | * If u.u_count is non-zero, then namei found space for the | |
506 | * new entry in the range u.u_offset to u.u_offset+u.u_count. | |
507 | * in the directory. To use this space, we may have to compact | |
508 | * the entries located there, by copying them together towards | |
509 | * the beginning of the block, leaving the free space in | |
510 | * one usable chunk at the end. | |
511 | */ | |
512 | ||
513 | /* | |
514 | * Increase size of directory if entry eats into new space. | |
515 | * This should never push the size past a new multiple of | |
516 | * DIRBLKSIZE. | |
517 | */ | |
518 | if (u.u_offset+u.u_count > u.u_pdir->i_size) { | |
4a0415d6 SL |
519 | /*ZZ*/ if (((u.u_offset+u.u_count-1)&~(DIRBLKSIZ-1)) != |
520 | /*ZZ*/ ((u.u_pdir->i_size-1)&~(DIRBLKSIZ-1))) { | |
521 | /*ZZ*/ panic("wdir: span"); | |
522 | /*ZZ*/ } | |
6bd0bb92 BJ |
523 | u.u_pdir->i_size = u.u_offset + u.u_count; |
524 | } | |
525 | ||
526 | /* | |
527 | * Get the block containing the space for the new directory | |
528 | * entry. | |
529 | */ | |
4a0415d6 | 530 | bp = blkatoff(u.u_pdir, u.u_offset, (char **)&dirbuf); |
6bd0bb92 BJ |
531 | if (bp == 0) |
532 | return; | |
6bd0bb92 BJ |
533 | |
534 | /* | |
535 | * Find space for the new entry. In the simple case, the | |
536 | * entry at offset base will have the space. If it does | |
537 | * not, then namei arranged that compacting the region | |
538 | * u.u_offset to u.u_offset+u.u_count would yield the space. | |
539 | */ | |
540 | ep = (struct direct *)dirbuf; | |
541 | dsize = DIRSIZ(ep); | |
542 | freespace = ep->d_reclen - dsize; | |
543 | for (loc = ep->d_reclen; loc < u.u_count; ) { | |
544 | nep = (struct direct *)(dirbuf + loc); | |
545 | if (ep->d_ino) { | |
546 | /* trim the existing slot */ | |
547 | ep->d_reclen = dsize; | |
548 | ep = (struct direct *)((char *)ep + dsize); | |
549 | } else { | |
550 | /* overwrite; nothing there; header is ours */ | |
551 | freespace += dsize; | |
552 | } | |
553 | dsize = DIRSIZ(nep); | |
554 | freespace += nep->d_reclen - dsize; | |
555 | loc += nep->d_reclen; | |
556 | /*ZZ*/if((loc&~0x1ff)!=(loc+nep->d_reclen-1&~0x1ff)) | |
557 | /*ZZ*/printf("wdir: compact loc %d reclen %d (dir %s/%d)\n",loc,nep->d_reclen, | |
558 | /*ZZ*/u.u_pdir->i_fs->fs_fsmnt,u.u_pdir->i_number); | |
559 | bcopy(nep, ep, dsize); | |
560 | } | |
561 | /* | |
562 | * Update the pointer fields in the previous entry (if any), | |
563 | * copy in the new entry, and write out the block. | |
564 | */ | |
565 | if (ep->d_ino == 0) { | |
566 | if (freespace + dsize < newentrysize) | |
567 | panic("wdir: compact1"); | |
568 | /*ZZ*/if(freespace+dsize>512)panic("wdir: compact screwup"); | |
569 | u.u_dent.d_reclen = freespace + dsize; | |
570 | } else { | |
571 | if (freespace < newentrysize) | |
572 | panic("wdir: compact2"); | |
573 | u.u_dent.d_reclen = freespace; | |
574 | /*ZZ*/if ((((char *)ep-bp->b_un.b_addr)&0x1ff)+dsize>512) panic("wdir: reclen"); | |
575 | ep->d_reclen = dsize; | |
576 | ep = (struct direct *)((char *)ep + dsize); | |
577 | } | |
578 | /*ZZ*/if((((char*)ep-bp->b_un.b_addr)&0x1ff)+u.u_dent.d_reclen>512)panic("wdir: botch"); | |
579 | bcopy(&u.u_dent, ep, newentrysize); | |
580 | bwrite(bp); | |
581 | u.u_pdir->i_flag |= IUPD|ICHG; | |
582 | iput(u.u_pdir); | |
583 | } | |
584 | ||
585 | dirremove() | |
586 | { | |
587 | register struct inode *dp = u.u_pdir; | |
588 | register struct fs *fs = dp->i_fs; | |
589 | register struct buf *bp; | |
590 | struct direct *ep; | |
591 | ||
6bd0bb92 BJ |
592 | if (u.u_count == 0) { |
593 | /* | |
594 | * First entry in block: set d_ino to zero. | |
595 | */ | |
596 | /*ZZ*/if(u.u_offset&0x1ff)printf("missed dir compact dir %s/%d off %d file %s\n" | |
597 | /*ZZ*/,dp->i_fs->fs_fsmnt,dp->i_number,u.u_offset,u.u_dent.d_name); | |
598 | u.u_base = (caddr_t)&u.u_dent; | |
599 | u.u_count = DIRSIZ(&u.u_dent); | |
4a0415d6 | 600 | u.u_segflg = 1; |
6bd0bb92 BJ |
601 | u.u_dent.d_ino = 0; |
602 | writei(dp); | |
603 | } else { | |
604 | /* | |
605 | * Collapse new free space into previous entry. | |
606 | */ | |
4a0415d6 | 607 | bp = blkatoff(dp, u.u_offset - u.u_count, (char **)&ep); |
6bd0bb92 BJ |
608 | if (bp == 0) |
609 | return (0); | |
610 | ep->d_reclen += u.u_dent.d_reclen; | |
611 | /*ZZ*/if((((char *)ep - bp->b_un.b_addr)&0x1ff)+u.u_dent.d_reclen > 512) | |
612 | /*ZZ*/ panic("unlink: reclen"); | |
613 | bwrite(bp); | |
614 | dp->i_flag |= IUPD|ICHG; | |
615 | } | |
616 | return (1); | |
10873320 | 617 | } |
6459ebe0 | 618 | |
4a0415d6 SL |
619 | /* |
620 | * Return buffer with contents of block "offset" | |
621 | * from the beginning of directory "ip". If "res" | |
622 | * is non-zero, fill it in with a pointer to the | |
623 | * remaining space in the directory. | |
624 | */ | |
6bd0bb92 | 625 | struct buf * |
4a0415d6 | 626 | blkatoff(ip, offset, res) |
6bd0bb92 BJ |
627 | struct inode *ip; |
628 | off_t offset; | |
629 | char **res; | |
6459ebe0 | 630 | { |
6bd0bb92 BJ |
631 | register struct fs *fs = ip->i_fs; |
632 | int lbn = lblkno(fs, offset); | |
633 | int base = blkoff(fs, offset); | |
634 | int bsize = blksize(fs, ip, lbn); | |
635 | int bn = fsbtodb(fs, bmap(ip, lbn, B_WRITE, base, bsize)); | |
636 | register struct buf *bp; | |
6459ebe0 | 637 | |
6bd0bb92 BJ |
638 | if (u.u_error) |
639 | return (0); | |
640 | bp = bread(ip->i_dev, bn, bsize); | |
641 | if (bp->b_flags & B_ERROR) { | |
642 | brelse(bp); | |
643 | return (0); | |
644 | } | |
645 | if (res) | |
646 | *res = bp->b_un.b_addr + base; | |
6bd0bb92 | 647 | return (bp); |
6459ebe0 | 648 | } |