xref: /illumos-gate/usr/src/cmd/fs.d/nfs/nfslog/dbtab.c (revision 9164a50bf932130cbb5097a16f6986873ce0e6e5)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * Code to maintain the runtime and on-disk filehandle mapping table for
28  * nfslog.
29  */
30 
31 #include <assert.h>
32 #include <errno.h>
33 #include <ctype.h>
34 #include <nfs/nfs.h>
35 #include <stdlib.h>
36 #include <stddef.h>
37 #include <string.h>
38 #include <strings.h>
39 #include <syslog.h>
40 #include <unistd.h>
41 #include <dirent.h>
42 #include <ndbm.h>
43 #include <time.h>
44 #include <libintl.h>
45 #include <sys/types.h>
46 #include <nfs/nfs.h>
47 #include <nfs/nfs_log.h>
48 #include "fhtab.h"
49 #include "nfslogd.h"
50 
51 #define	ROUNDUP32(val)		(((val) + 3) & ~3)
52 
53 /*
54  * It is important that this string not match the length of the
55  * file handle key length NFS_FHMAXDATA
56  */
57 #define	DB_VERSION_STRING	"NFSLOG_DB_VERSION"
58 #define	DB_VERSION		"1"
59 
60 #define	MAX_PRUNE_REC_CNT	100000
61 
62 fhandle_t	public_fh = { 0 };
63 
64 struct db_list {
65 	fsid_t		fsid;		/* filesystem fsid */
66 	char		*path;		/* dbm filepair path */
67 	DBM		*db;		/* open dbm database */
68 	bool_t		getall;		/* TRUE if all dbm for prefix open */
69 	struct db_list	*next;		/* next db */
70 };
71 
72 static struct db_list *db_fs_list = NULL;
73 static	char	err_str[] = "DB I/O error has occurred";
74 struct link_keys {
75 	fh_secondary_key	lnkey;
76 	int			lnsize;
77 	struct link_keys	*next;
78 };
79 extern int debug;
80 extern time_t mapping_update_interval;
81 extern time_t prune_timeout;
82 
83 static int fill_link_key(char *linkkey, fhandle_t *dfh, char *name);
84 static struct db_list *db_get_db(char *fhpath, fsid_t *fsid, int *errorp,
85 	int create_flag);
86 static struct db_list *db_get_all_databases(char *fhpath, bool_t getall);
87 static void debug_print_fhlist(FILE *fp, fhlist_ent *fhrecp);
88 static void debug_print_linkinfo(FILE *fp, linkinfo_ent *fhrecp);
89 static void debug_print_key(FILE *fp, char *str1, char *str2, char *key,
90 	int ksize);
91 static void debug_print_key_and_data(FILE *fp, char *str1, char *str2,
92 	char *key, int ksize, char *data, int dsize);
93 static int store_record(struct db_list *dbp, void *keyaddr, int keysize,
94 	void *dataaddr, int datasize, char *str);
95 static void *fetch_record(struct db_list *dbp, void *keyaddr, int keysize,
96 	void *dataaddr, int *errorp, char *str);
97 static int delete_record(struct db_list *dbp, void *keyaddr, int keysize,
98 	char *str);
99 static int db_update_fhrec(struct db_list *dbp, void *keyaddr, int keysize,
100 	fhlist_ent *fhrecp, char *str);
101 static int db_update_linkinfo(struct db_list *dbp, void *keyaddr, int keysize,
102 	linkinfo_ent *linkp, char *str);
103 static fhlist_ent *create_primary_struct(struct db_list *dbp, fhandle_t *dfh,
104 	char *name, fhandle_t *fh, uint_t flags, fhlist_ent *fhrecp,
105 	int *errorp);
106 static fhlist_ent *db_add_primary(struct db_list *dbp, fhandle_t *dfh,
107 	char *name, fhandle_t *fh, uint_t flags, fhlist_ent *fhrecp,
108 	int *errorp);
109 static linkinfo_ent *get_next_link(struct db_list *dbp, char *linkkey,
110 	int *linksizep, linkinfo_ent *linkp, void **cookiep,
111 	int *errorp, char *msg);
112 static void free_link_cookies(void *cookie);
113 static void add_mc_path(struct db_list *dbp, fhandle_t *dfh, char *name,
114 	fhlist_ent *fhrecp, linkinfo_ent *linkp, int *errorp);
115 static linkinfo_ent *create_link_struct(struct db_list *dbp, fhandle_t *dfh,
116 	char *name, fhlist_ent *fhrecp, int *errorp);
117 static int db_add_secondary(struct db_list *dbp, fhandle_t *dfh, char *name,
118 	fhandle_t *fh, fhlist_ent *fhrecp);
119 static linkinfo_ent *update_next_link(struct db_list *dbp, char *nextkey,
120 	int nextsize, char *prevkey, int prevsize, int *errorp);
121 static int update_prev_link(struct db_list *dbp, char *nextkey, int nextsize,
122 	char *prevkey, int prevsize);
123 static linkinfo_ent *update_linked_list(struct db_list *dbp, char *nextkey,
124 	int nextsize, char *prevkey, int prevsize, int *errorp);
125 static int db_update_primary_new_head(struct db_list *dbp,
126 	linkinfo_ent *dellinkp, linkinfo_ent *nextlinkp, fhlist_ent *fhrecp);
127 static int delete_link_by_key(struct db_list *dbp, char *linkkey,
128 	int *linksizep, int *errorp, char *errstr);
129 static int delete_link(struct db_list *dbp, fhandle_t *dfh, char *name,
130 	char *nextlinkkey, int *nextlinksizep, int *errorp, char *errstr);
131 
132 /*
133  * The following functions do the actual database I/O. Currently use DBM.
134  */
135 
136 /*
137  * The "db_*" functions are functions that access the database using
138  * database-specific calls. Currently the only database supported is
139  * dbm. Because of the limitations of this database, in particular when
140  * it comes to manipulating records with the same key, or using multiple keys,
141  * the following design decisions have been made:
142  *
143  *	Each file system has a separate dbm file, which are kept open as
144  *		accessed, listed in a linked list.
145  *	Two possible access mode are available for each file - either by
146  *		file handle, or by directory file handle and name. Since
147  *		dbm does not allow multiple keys, we will have a primary
148  *		and secondary key for each file/link.
149  *	The primary key is the pair (inode,gen) which can be obtained
150  *		from the file handle. This points to a record with
151  *		the full file handle and the secondary key (dfh-key,name)
152  *		for one of the links.
153  *	The secondary key is the pair (dfh-key,name) where dfh-key is
154  *		the primary key for the directory and the name is the
155  *		link name. It points to a record that contains the primary
156  *		key for the file and to the previous and next hard link
157  *		found for this file (if they exist).
158  *
159  * Summary of operations:
160  *	Adding a new file: Create the primary record and secondary (link)
161  *		record and add both to the database. The link record
162  *		would have prev and next links set to NULL.
163  *
164  *	Adding a link to a file in the database: Add the link record,
165  *		to the head of the links list (i.e. prev = NULL, next =
166  *		secondary key recorded in the primary record). Update
167  *		the primary record to point to the new link, and the
168  *		secondary record for the old head of list to point to new.
169  *
170  *	Deleting a file: Delete the link record. If it is the last link
171  *		then mark the primary record as deleted but don't delete
172  *		that one from the database (in case some clients still
173  *		hold the file handle). If there are other links, and the
174  *		deleted link is the head of the list (in the primary
175  *		record), update the primary record with the new head.
176  *
177  *	Renaming a file: Add the new link and then delete the old one.
178  *
179  *	Lookup by file handle (read, write, lookup, etc.) - fetch primary rec.
180  *	Lookup by dir info (delete, link, rename) - fetch secondary rec.
181  *
182  *	XXX NOTE: The code is written single-threaded. To make it multi-
183  *	threaded, the following considerations must be made:
184  *	1. Changes/access to the db list must be atomic.
185  *	2. Changes/access for a specific file handle must be atomic
186  *	   (example: deleting a link may affect up to 4 separate database
187  *	   entries: the deleted link, the prev and next links if exist,
188  *	   and the filehandle entry, if it points to the deleted link -
189  *	   these changes must be atomic).
190  */
191 
192 /*
193  * Create a link key given directory fh and name
194  */
195 static int
196 fill_link_key(char *linkkey, fhandle_t *dfh, char *name)
197 {
198 	int	linksize, linksize32;
199 
200 	(void) memcpy(linkkey, &dfh->fh_data, dfh->fh_len);
201 	(void) strcpy(&linkkey[dfh->fh_len], name);
202 	linksize = dfh->fh_len + strlen(name) + 1;
203 	linksize32 = ROUNDUP32(linksize);
204 	if (linksize32 > linksize)
205 		bzero(&linkkey[linksize], linksize32 - linksize);
206 	return (linksize32);
207 }
208 
209 /*
210  * db_get_db - gets the database for the filesystem, or creates one
211  * if none exists. Return the pointer for the database in *dbpp if success.
212  * Return 0 for success, error code otherwise.
213  */
214 static struct db_list *
215 db_get_db(char *fhpath, fsid_t *fsid, int *errorp, int create_flag)
216 {
217 	struct db_list	*p, *newp;
218 	char		fsidstr[30];
219 	datum		key, data;
220 
221 	*errorp = 0;
222 	for (p = db_fs_list;
223 		(p != NULL) && memcmp(&p->fsid, fsid, sizeof (*fsid));
224 		p = p->next);
225 	if (p != NULL) {
226 		/* Found it */
227 		return (p);
228 	}
229 	/* Create it */
230 	if ((newp = calloc(1, sizeof (*newp))) == NULL) {
231 		*errorp = errno;
232 		syslog(LOG_ERR, gettext(
233 			"db_get_db: malloc db failed: Error %s"),
234 			strerror(*errorp));
235 		return (NULL);
236 	}
237 	(void) sprintf(fsidstr, "%08x%08x", fsid->val[0], fsid->val[1]);
238 	if ((newp->path = malloc(strlen(fhpath) + 2 + strlen(fsidstr)))
239 		== NULL) {
240 		*errorp = errno;
241 		syslog(LOG_ERR, gettext(
242 			"db_get_db: malloc dbpath failed: Error %s"),
243 			strerror(*errorp));
244 		goto err_exit;
245 	}
246 	(void) sprintf(newp->path, "%s.%s", fhpath, fsidstr);
247 	/*
248 	 * The open mode is masked by UMASK.
249 	 */
250 	if ((newp->db = dbm_open(newp->path, create_flag | O_RDWR, 0666))
251 		== NULL) {
252 		*errorp = errno;
253 		syslog(LOG_ERR, gettext(
254 			"db_get_db: dbm_open db '%s' failed: Error %s"),
255 			newp->path, strerror(*errorp));
256 		if (*errorp == 0)	/* should not happen but may */
257 			*errorp = -1;
258 		goto err_exit;
259 	}
260 	/*
261 	 * Add the version identifier (have to check first in the
262 	 * case the db exists)
263 	 */
264 	key.dptr = DB_VERSION_STRING;
265 	key.dsize = strlen(DB_VERSION_STRING);
266 	data = dbm_fetch(newp->db, key);
267 	if (data.dptr == NULL) {
268 		data.dptr = DB_VERSION;
269 		data.dsize = strlen(DB_VERSION);
270 		(void) dbm_store(newp->db, key, data, DBM_INSERT);
271 	}
272 
273 	(void) memcpy(&newp->fsid, fsid, sizeof (*fsid));
274 	newp->next = db_fs_list;
275 	db_fs_list = newp;
276 	if (debug > 1) {
277 		(void) printf("db_get_db: db %s opened\n", newp->path);
278 	}
279 	return (newp);
280 
281 err_exit:
282 	if (newp != NULL) {
283 		if (newp->db != NULL) {
284 			dbm_close(newp->db);
285 		}
286 		if (newp->path != NULL) {
287 			free(newp->path);
288 		}
289 		free(newp);
290 	}
291 	return (NULL);
292 }
293 
294 /*
295  * db_get_all_databases - gets the database for any filesystem. This is used
296  * when any database will do - typically to retrieve the path for the
297  * public filesystem. If any database is open - return the first one,
298  * otherwise, search for it using fhpath. If getall is TRUE, open all
299  * matching databases, and mark them (to indicate that all such were opened).
300  * Return the pointer for a matching database if success.
301  */
302 static struct db_list *
303 db_get_all_databases(char *fhpath, bool_t getall)
304 {
305 	char		*dirptr, *fhdir, *fhpathname;
306 	int		len, error;
307 	DIR		*dirp;
308 	struct dirent	*dp;
309 	fsid_t		fsid;
310 	struct db_list	*dbp, *ret_dbp;
311 
312 	for (dbp = db_fs_list; dbp != NULL; dbp = dbp->next) {
313 		if (strncmp(fhpath, dbp->path, strlen(fhpath)) == 0)
314 			break;
315 	}
316 	if (dbp != NULL) {
317 		/*
318 		 * if one database for that prefix is open, and  either only
319 		 * one is needed, or already opened all such databases,
320 		 * return here without exhaustive search
321 		 */
322 		if (!getall || dbp->getall)
323 			return (dbp);
324 	}
325 	if ((fhdir = strdup(fhpath)) == NULL) {
326 		syslog(LOG_ERR, gettext(
327 			"db_get_all_databases: strdup '%s' Error '%s*'"),
328 			fhpath, strerror(errno));
329 		return (NULL);
330 	}
331 	fhpathname = NULL;
332 	ret_dbp = NULL;
333 	if ((dirptr = strrchr(fhdir, '/')) == NULL) {
334 		/* no directory */
335 		goto exit;
336 	}
337 	if ((fhpathname = strdup(&dirptr[1])) == NULL) {
338 		syslog(LOG_ERR, gettext(
339 			"db_get_all_databases: strdup '%s' Error '%s*'"),
340 			&dirptr[1], strerror(errno));
341 		goto exit;
342 	}
343 	/* Terminate fhdir string at last '/' */
344 	dirptr[1] = '\0';
345 	/* Search the directory */
346 	if (debug > 2) {
347 		(void) printf("db_get_all_databases: search '%s' for '%s*'\n",
348 			fhdir, fhpathname);
349 	}
350 	if ((dirp = opendir(fhdir)) == NULL) {
351 		syslog(LOG_ERR, gettext(
352 			"db_get_all_databases: opendir '%s' Error '%s*'"),
353 			fhdir, strerror(errno));
354 		goto exit;
355 	}
356 	len = strlen(fhpathname);
357 	while ((dp = readdir(dirp)) != NULL) {
358 		if (strncmp(fhpathname, dp->d_name, len) == 0) {
359 			dirptr = &dp->d_name[len + 1];
360 			if (*(dirptr - 1) != '.') {
361 				continue;
362 			}
363 			(void) sscanf(dirptr, "%08lx%08lx",
364 			    (ulong_t *)&fsid.val[0], (ulong_t *)&fsid.val[1]);
365 			dbp = db_get_db(fhpath, &fsid, &error, 0);
366 			if (dbp != NULL) {
367 				ret_dbp = dbp;
368 				if (!getall)
369 					break;
370 				dbp->getall = TRUE;
371 			}
372 		}
373 	}
374 	(void) closedir(dirp);
375 exit:
376 	if (fhpathname != NULL)
377 		free(fhpathname);
378 	if (fhdir != NULL)
379 		free(fhdir);
380 	return (ret_dbp);
381 }
382 
383 static void
384 debug_print_key(FILE *fp, char *str1, char *str2, char *key, int ksize)
385 {
386 	(void) fprintf(fp, "%s: %s key (%d) ", str1, str2, ksize);
387 	debug_opaque_print(fp, key, ksize);
388 	/* may be inode,name - try to print the fields */
389 	if (ksize >= NFS_FHMAXDATA) {
390 		(void) fprintf(fp, ": inode ");
391 		debug_opaque_print(fp, &key[2], sizeof (int));
392 		(void) fprintf(fp, ", gen ");
393 		debug_opaque_print(fp, &key[2 + sizeof (int)], sizeof (int));
394 		if (ksize > NFS_FHMAXDATA) {
395 			(void) fprintf(fp, ", name '%s'", &key[NFS_FHMAXDATA]);
396 		}
397 	}
398 	(void) fprintf(fp, "\n");
399 }
400 
401 static void
402 debug_print_linkinfo(FILE *fp, linkinfo_ent *linkp)
403 {
404 	if (linkp == NULL)
405 		return;
406 	(void) fprintf(fp, "linkinfo:\ndfh: ");
407 	debug_opaque_print(fp, (void *)&linkp->dfh, sizeof (linkp->dfh));
408 	(void) fprintf(fp, "\nname: '%s'", LN_NAME(linkp));
409 	(void) fprintf(fp, "\nmtime 0x%x, atime 0x%x, flags 0x%x, reclen %d\n",
410 		linkp->mtime, linkp->atime, linkp->flags, linkp->reclen);
411 	(void) fprintf(fp, "offsets: fhkey %d, name %d, next %d, prev %d\n",
412 		linkp->fhkey_offset, linkp->name_offset, linkp->next_offset,
413 		linkp->prev_offset);
414 	debug_print_key(fp, "fhkey", "", LN_FHKEY(linkp), LN_FHKEY_LEN(linkp));
415 	debug_print_key(fp, "next", "", LN_NEXT(linkp), LN_NEXT_LEN(linkp));
416 	debug_print_key(fp, "prev", "", LN_PREV(linkp), LN_PREV_LEN(linkp));
417 }
418 
419 static void
420 debug_print_fhlist(FILE *fp, fhlist_ent *fhrecp)
421 {
422 	if (fhrecp == NULL)
423 		return;
424 	(void) fprintf(fp, "fhrec:\nfh: ");
425 	debug_opaque_print(fp, (void *)&fhrecp->fh, sizeof (fhrecp->fh));
426 	(void) fprintf(fp, "name '%s', dfh: ", fhrecp->name);
427 	debug_opaque_print(fp, (void *)&fhrecp->dfh, sizeof (fhrecp->dfh));
428 	(void) fprintf(fp, "\nmtime 0x%x, atime 0x%x, flags 0x%x, reclen %d\n",
429 		fhrecp->mtime, fhrecp->atime, fhrecp->flags, fhrecp->reclen);
430 }
431 
432 static void
433 debug_print_key_and_data(FILE *fp, char *str1, char *str2, char *key,
434 	int ksize, char *data, int dsize)
435 {
436 	debug_print_key(fp, str1, str2, key, ksize);
437 	(void) fprintf(fp, " ==> (%p,%d)\n", (void *)data, dsize);
438 	if (ksize > NFS_FHMAXDATA) {
439 		linkinfo_ent inf;
440 		/* probably a link struct */
441 		(void) memcpy(&inf, data, sizeof (linkinfo_ent));
442 		debug_print_linkinfo(fp, &inf);
443 	} else if (ksize == NFS_FHMAXDATA) {
444 		fhlist_ent inf;
445 		/* probably an fhlist struct */
446 		(void) memcpy(&inf, data, sizeof (linkinfo_ent));
447 		debug_print_fhlist(fp, &inf);
448 	} else {
449 		/* don't know... */
450 		debug_opaque_print(fp, data, dsize);
451 	}
452 }
453 
454 /*
455  * store_record - store the record in the database and return 0 for success
456  * or error code otherwise.
457  */
458 static int
459 store_record(struct db_list *dbp, void *keyaddr, int keysize, void *dataaddr,
460 	int datasize, char *str)
461 {
462 	datum	key, data;
463 	int	error;
464 	char	*errfmt = "store_record: dbm_store failed, Error: %s\n";
465 	char	*err;
466 
467 	errno = 0;
468 	key.dptr = keyaddr;
469 	key.dsize = keysize;
470 	data.dptr = dataaddr;
471 	data.dsize = datasize;
472 
473 	if (debug > 2) {
474 		debug_print_key_and_data(stdout, str, "dbm_store:\n    ",
475 			key.dptr, key.dsize, data.dptr, data.dsize);
476 	}
477 	if (dbm_store(dbp->db, key, data, DBM_REPLACE) < 0) {
478 		/* Could not store */
479 		error = dbm_error(dbp->db);
480 		dbm_clearerr(dbp->db);
481 
482 		if (error) {
483 			if (errno)
484 				err = strerror(errno);
485 			else {
486 				err = err_str;
487 				errno = EIO;
488 			}
489 		} else { /* should not happen but sometimes does */
490 			err = err_str;
491 			errno = -1;
492 		}
493 		if (debug) {
494 			debug_print_key(stderr, str, "store_record:"
495 				"dbm_store:\n", key.dptr, key.dsize);
496 			(void) fprintf(stderr, errfmt, err);
497 		} else
498 			syslog(LOG_ERR, gettext(errfmt), err);
499 		return (errno);
500 	}
501 	return (0);
502 }
503 
504 /*
505  * fetch_record - fetch the record from the database and return 0 for success
506  * and errno for failure.
507  * dataaddr is an optional valid address for the result. If dataaddr
508  * is non-null, then that memory is already alloc'd. Else, alloc it, and
509  * the caller must free the returned struct when done.
510  */
511 static void *
512 fetch_record(struct db_list *dbp, void *keyaddr, int keysize, void *dataaddr,
513 	int *errorp, char *str)
514 {
515 	datum	key, data;
516 	char	*errfmt = "fetch_record: dbm_fetch failed, Error: %s\n";
517 	char	*err;
518 
519 	errno = 0;
520 	*errorp = 0;
521 	key.dptr = keyaddr;
522 	key.dsize = keysize;
523 
524 	data = dbm_fetch(dbp->db, key);
525 	if (data.dptr == NULL) {
526 		/* see if there is a database error */
527 		if (dbm_error(dbp->db)) {
528 			/* clear and report the database error */
529 			dbm_clearerr(dbp->db);
530 			*errorp = EIO;
531 			err = strerror(*errorp);
532 			syslog(LOG_ERR, gettext(errfmt), err);
533 		} else {
534 			/* primary record not in database */
535 			*errorp = ENOENT;
536 		}
537 		if (debug > 3) {
538 			err = strerror(*errorp);
539 			debug_print_key(stderr, str, "fetch_record:"
540 				"dbm_fetch:\n", key.dptr, key.dsize);
541 			(void) fprintf(stderr, errfmt, err);
542 		}
543 		return (NULL);
544 	}
545 
546 	/* copy to local struct because dbm may return non-aligned pointers */
547 	if ((dataaddr == NULL) &&
548 	    ((dataaddr = malloc(data.dsize)) == NULL)) {
549 		*errorp = errno;
550 		syslog(LOG_ERR, gettext(
551 			"%s: dbm_fetch - malloc %ld: Error %s"),
552 			str, data.dsize, strerror(*errorp));
553 		return (NULL);
554 	}
555 	(void) memcpy(dataaddr, data.dptr, data.dsize);
556 	if (debug > 3) {
557 		debug_print_key_and_data(stdout, str, "fetch_record:"
558 			"dbm_fetch:\n", key.dptr, key.dsize,
559 			dataaddr, data.dsize);
560 	}
561 	*errorp = 0;
562 	return (dataaddr);
563 }
564 
565 /*
566  * delete_record - delete the record from the database and return 0 for success
567  * or error code for failure.
568  */
569 static int
570 delete_record(struct db_list *dbp, void *keyaddr, int keysize, char *str)
571 {
572 	datum	key;
573 	int	error = 0;
574 	char	*errfmt = "delete_record: dbm_delete failed, Error: %s\n";
575 	char	*err;
576 
577 	errno = 0;
578 	key.dptr = keyaddr;
579 	key.dsize = keysize;
580 
581 	if (debug > 2) {
582 		debug_print_key(stdout, str, "delete_record:"
583 			"dbm_delete:\n", key.dptr, key.dsize);
584 	}
585 	if (dbm_delete(dbp->db, key) < 0) {
586 		error = dbm_error(dbp->db);
587 		dbm_clearerr(dbp->db);
588 
589 		if (error) {
590 			if (errno)
591 				err = strerror(errno);
592 			else {
593 				err = err_str;
594 				errno = EIO;
595 			}
596 		} else { /* should not happen but sometimes does */
597 			err = err_str;
598 			errno = -1;
599 		}
600 		if (debug) {
601 			debug_print_key(stderr, str, "delete_record:"
602 				"dbm_delete:\n", key.dptr, key.dsize);
603 			(void) fprintf(stderr, errfmt, err);
604 		} else
605 			syslog(LOG_ERR, gettext(errfmt), err);
606 	}
607 	return (errno);
608 }
609 
610 /*
611  * db_update_fhrec - puts fhrec in db with updated atime if more than
612  * mapping_update_interval seconds passed. Return 0 if success, error otherwise.
613  */
614 static int
615 db_update_fhrec(struct db_list *dbp, void *keyaddr, int keysize,
616 	fhlist_ent *fhrecp, char *str)
617 {
618 	time_t	cur_time = time(0);
619 
620 	if (difftime(cur_time, fhrecp->atime) >= mapping_update_interval) {
621 		fhrecp->atime = cur_time;
622 		return (store_record(dbp, keyaddr, keysize,
623 				fhrecp, fhrecp->reclen, str));
624 	}
625 	return (0);
626 }
627 
628 /*
629  * db_update_linkinfo - puts linkinfo in db with updated atime if more than
630  * mapping_update_interval seconds passed. Return 0 if success, error otherwise.
631  */
632 static int
633 db_update_linkinfo(struct db_list *dbp, void *keyaddr, int keysize,
634 	linkinfo_ent *linkp, char *str)
635 {
636 	time_t	cur_time = time(0);
637 
638 	if (difftime(cur_time, linkp->atime) >= mapping_update_interval) {
639 		linkp->atime = cur_time;
640 		return (store_record(dbp, keyaddr, keysize,
641 				linkp, linkp->reclen, str));
642 	}
643 	return (0);
644 }
645 
646 /*
647  * create_primary_struct - add primary record to the database.
648  * Database must be open when this function is called.
649  * If success, return the added database entry. fhrecp may be used to
650  * provide an existing memory area, else malloc it. If failed, *errorp
651  * contains the error code and return NULL.
652  */
653 static fhlist_ent *
654 create_primary_struct(struct db_list *dbp, fhandle_t *dfh, char *name,
655 	fhandle_t *fh, uint_t flags, fhlist_ent *fhrecp, int *errorp)
656 {
657 	int		reclen, reclen1;
658 	fhlist_ent	*new_fhrecp = fhrecp;
659 
660 	reclen1 = offsetof(fhlist_ent, name) + strlen(name) + 1;
661 	reclen = ROUNDUP32(reclen1);
662 	if (fhrecp == NULL) {	/* allocated the memory */
663 		if ((new_fhrecp = malloc(reclen)) == NULL) {
664 			*errorp = errno;
665 			syslog(LOG_ERR, gettext(
666 				"create_primary_struct: malloc %d Error %s"),
667 				reclen, strerror(*errorp));
668 			return (NULL);
669 		}
670 	}
671 	/* Fill in the fields */
672 	(void) memcpy(&new_fhrecp->fh, fh, sizeof (*fh));
673 	(void) memcpy(&new_fhrecp->dfh, dfh, sizeof (*dfh));
674 	new_fhrecp->flags = flags;
675 	if (dfh == &public_fh)
676 		new_fhrecp->flags |= PUBLIC_PATH;
677 	else
678 		new_fhrecp->flags &= ~PUBLIC_PATH;
679 	new_fhrecp->mtime = time(0);
680 	new_fhrecp->atime = new_fhrecp->mtime;
681 	(void) strcpy(new_fhrecp->name, name);
682 	if (reclen1 < reclen) {
683 		bzero((char *)((uintptr_t)new_fhrecp + reclen1),
684 			reclen - reclen1);
685 	}
686 	new_fhrecp->reclen = reclen;
687 	*errorp = store_record(dbp, &fh->fh_data, fh->fh_len, new_fhrecp,
688 			new_fhrecp->reclen, "create_primary_struct");
689 	if (*errorp != 0) {
690 		/* Could not store */
691 		if (fhrecp == NULL)	/* caller did not supply pointer */
692 			free(new_fhrecp);
693 		return (NULL);
694 	}
695 	return (new_fhrecp);
696 }
697 
698 /*
699  * db_add_primary - add primary record to the database.
700  * If record already in and live, return it (even if for a different link).
701  * If in database but marked deleted, replace it. If not in database, add it.
702  * Database must be open when this function is called.
703  * If success, return the added database entry. fhrecp may be used to
704  * provide an existing memory area, else malloc it. If failed, *errorp
705  * contains the error code and return NULL.
706  */
707 static fhlist_ent *
708 db_add_primary(struct db_list *dbp, fhandle_t *dfh, char *name, fhandle_t *fh,
709 	uint_t flags, fhlist_ent *fhrecp, int *errorp)
710 {
711 	fhlist_ent	*new_fhrecp;
712 	fh_primary_key	fhkey;
713 
714 	if (debug > 2)
715 		(void) printf("db_add_primary entered: name '%s'\n", name);
716 
717 	bcopy(&fh->fh_data, fhkey, fh->fh_len);
718 	new_fhrecp = fetch_record(dbp, fhkey, fh->fh_len, (void *)fhrecp,
719 			errorp, "db_add_primary");
720 	if (new_fhrecp != NULL) {
721 		/* primary record is in the database */
722 		/* Update atime if needed */
723 		*errorp = db_update_fhrec(dbp, fhkey, fh->fh_len, new_fhrecp,
724 				"db_add_primary put fhrec");
725 		if (debug > 2)
726 			(void) printf("db_add_primary exits(2): name '%s'\n",
727 				name);
728 		return (new_fhrecp);
729 	}
730 	/* primary record not in database - create it */
731 	new_fhrecp = create_primary_struct(dbp, dfh, name, fh, flags,
732 			fhrecp, errorp);
733 	if (new_fhrecp == NULL) {
734 		/* Could not store */
735 		if (debug > 2)
736 			(void) printf(
737 				"db_add_primary exits(1): name '%s' Error %s\n",
738 				name, ((*errorp >= 0) ? strerror(*errorp) :
739 					"Unknown"));
740 
741 		return (NULL);
742 	}
743 	if (debug > 2)
744 		(void) printf("db_add_primary exits(0): name '%s'\n", name);
745 	return (new_fhrecp);
746 }
747 
748 /*
749  * get_next_link - get and check the next link in the chain.
750  * Re-use space if linkp param non-null. Also set *linkkey and *linksizep
751  * to values for next link (*linksizep set to 0 if last link).
752  * cookie is used to detect corrupted link entries XXXXXXX
753  * Return the link pointer or NULL if none.
754  */
755 static linkinfo_ent *
756 get_next_link(struct db_list *dbp, char *linkkey, int *linksizep,
757 	linkinfo_ent *linkp, void **cookiep, int *errorp, char *msg)
758 {
759 	int	linksize, nextsize;
760 	char	*nextkey;
761 	linkinfo_ent *new_linkp = linkp;
762 	struct link_keys *lnp;
763 
764 	linksize = *linksizep;
765 	if (linksize == 0)
766 		return (NULL);
767 	*linksizep = 0;
768 	new_linkp = fetch_record(dbp, linkkey, linksize, (void *)linkp,
769 			errorp, msg);
770 	if (new_linkp == NULL)
771 		return (NULL);
772 
773 	/* Set linkkey to point to next record */
774 	nextsize = LN_NEXT_LEN(new_linkp);
775 	if (nextsize == 0)
776 		return (new_linkp);
777 
778 	/* Add this key to the cookie list */
779 	if ((lnp = malloc(sizeof (struct link_keys))) == NULL) {
780 		syslog(LOG_ERR, gettext("get_next_key: malloc error %s\n"),
781 			strerror(errno));
782 		if ((new_linkp != NULL) && (linkp == NULL))
783 			free(new_linkp);
784 		return (NULL);
785 	}
786 	(void) memcpy(lnp->lnkey, linkkey, linksize);
787 	lnp->lnsize = linksize;
788 	lnp->next = *(struct link_keys **)cookiep;
789 	*cookiep = (void *)lnp;
790 
791 	/* Make sure record does not point to itself or other internal loops */
792 	nextkey = LN_NEXT(new_linkp);
793 	for (; lnp != NULL; lnp = lnp->next) {
794 		if ((nextsize == lnp->lnsize) && (memcmp(
795 			lnp->lnkey, nextkey, nextsize) == 0)) {
796 
797 			/*
798 			 * XXX This entry's next pointer points to
799 			 * itself. This is only a work-around, remove
800 			 * this check once bug 4203186 is fixed.
801 			 */
802 			if (debug) {
803 				(void) fprintf(stderr,
804 				"%s: get_next_link: last record invalid.\n",
805 					msg);
806 				debug_print_key_and_data(stderr, msg,
807 					"invalid rec:\n ", linkkey, linksize,
808 					(char *)new_linkp, new_linkp->reclen);
809 			}
810 			/* Return as if this is the last link */
811 			return (new_linkp);
812 		}
813 	}
814 	(void) memcpy(linkkey, nextkey, nextsize);
815 	*linksizep = nextsize;
816 	return (new_linkp);
817 }
818 
819 /*
820  * free_link_cookies - free the cookie list
821  */
822 static void
823 free_link_cookies(void *cookie)
824 {
825 	struct link_keys *dellnp, *lnp;
826 
827 	lnp = (struct link_keys *)cookie;
828 	while (lnp != NULL) {
829 		dellnp = lnp;
830 		lnp = lnp->next;
831 		free(dellnp);
832 	}
833 }
834 
835 /*
836  * add_mc_path - add a mc link to a file that has other links. Add it at end
837  * of linked list. Called when it's known there are other links.
838  */
839 static void
840 add_mc_path(struct db_list *dbp, fhandle_t *dfh, char *name,
841 	fhlist_ent *fhrecp, linkinfo_ent *linkp, int *errorp)
842 {
843 	fh_secondary_key	linkkey;
844 	int			linksize, len;
845 	linkinfo_ent		lastlink, *lastlinkp;
846 	void			*cookie;
847 
848 	linksize = fill_link_key(linkkey, &fhrecp->dfh, fhrecp->name);
849 	cookie = NULL;
850 	do {
851 		lastlinkp = get_next_link(dbp, linkkey, &linksize, &lastlink,
852 				&cookie, errorp, "add_mc_path");
853 	} while (linksize > 0);
854 	free_link_cookies(cookie);
855 	/* reached end of list */
856 	if (lastlinkp == NULL) {
857 		/* nothing to do */
858 		if (debug > 1) {
859 			(void) fprintf(stderr, "add_mc_path link is null\n");
860 		}
861 		return;
862 	}
863 	/* Add new link after last link */
864 	/*
865 	 * next - link key for the next in the list - add at end so null.
866 	 * prev - link key for the previous link in the list.
867 	 */
868 	linkp->prev_offset = linkp->next_offset;	/* aligned */
869 	linksize = fill_link_key(LN_PREV(linkp), &lastlinkp->dfh,
870 				LN_NAME(lastlinkp));
871 	linkp->reclen = linkp->prev_offset + linksize;	/* aligned */
872 
873 	/* Add the link information to the database */
874 	linksize = fill_link_key(linkkey, dfh, name);
875 	*errorp = store_record(dbp, linkkey, linksize,
876 			linkp, linkp->reclen, "add_mc_path");
877 	if (*errorp != 0)
878 		return;
879 
880 	/* Now update previous last link to point forward to new link */
881 	/* Copy prev link out since it's going to be overwritten */
882 	linksize = LN_PREV_LEN(lastlinkp);
883 	(void) memcpy(linkkey, LN_PREV(lastlinkp), linksize);
884 	/* Update previous last link to point to new one */
885 	len = fill_link_key(LN_NEXT(lastlinkp), dfh, name);
886 	lastlinkp->prev_offset = lastlinkp->next_offset + len;	/* aligned */
887 	(void) memcpy(LN_PREV(lastlinkp), linkkey, linksize);
888 	lastlinkp->reclen = lastlinkp->prev_offset + linksize;
889 	/* Update the link information to the database */
890 	linksize = fill_link_key(linkkey, &lastlinkp->dfh, LN_NAME(lastlinkp));
891 	*errorp = store_record(dbp, linkkey, linksize,
892 			lastlinkp, lastlinkp->reclen, "add_mc_path prev");
893 }
894 
895 /*
896  * create_link_struct - create the secondary struct.
897  * (dfh,name) is the secondary key, fhrec is the primary record for the file
898  * and linkpp is a place holder for the record (could be null).
899  * Insert the record to the database.
900  * Return 0 if success, error otherwise.
901  */
902 static linkinfo_ent *
903 create_link_struct(struct db_list *dbp, fhandle_t *dfh, char *name,
904 	fhlist_ent *fhrecp, int *errorp)
905 {
906 	fh_secondary_key	linkkey;
907 	int			len, linksize;
908 	linkinfo_ent		*linkp;
909 
910 	if ((linkp = malloc(sizeof (linkinfo_ent))) == NULL) {
911 		*errorp = errno;
912 		syslog(LOG_ERR, gettext(
913 			"create_link_struct: malloc failed: Error %s"),
914 			strerror(*errorp));
915 		return (NULL);
916 	}
917 	if (dfh == &public_fh)
918 		linkp->flags |= PUBLIC_PATH;
919 	else
920 		linkp->flags &= ~PUBLIC_PATH;
921 	(void) memcpy(&linkp->dfh, dfh, sizeof (*dfh));
922 	linkp->mtime = time(0);
923 	linkp->atime = linkp->mtime;
924 	/* Calculate offsets of variable fields */
925 	/* fhkey - primary key (inode/gen) */
926 	/* name - component name (in directory dfh) */
927 	linkp->fhkey_offset = ROUNDUP32(offsetof(linkinfo_ent, varbuf));
928 	len = fill_link_key(LN_FHKEY(linkp), &fhrecp->fh, name);
929 	linkp->name_offset = linkp->fhkey_offset + fhrecp->fh.fh_len;
930 	linkp->next_offset = linkp->fhkey_offset + len;	/* aligned */
931 	/*
932 	 * next - link key for the next link in the list - NULL if it's
933 	 * the first link. If this is the public fs, only one link allowed.
934 	 * Avoid setting a multi-component path as primary path,
935 	 * unless no choice.
936 	 */
937 	len = 0;
938 	if (memcmp(&fhrecp->dfh, dfh, sizeof (*dfh)) ||
939 	    strcmp(fhrecp->name, name)) {
940 		/* different link than the one that's in the record */
941 		if (dfh == &public_fh) {
942 			/* parent is public fh - either multi-comp or root */
943 			if (memcmp(&fhrecp->fh, &public_fh,
944 				sizeof (public_fh))) {
945 				/* multi-comp path */
946 				add_mc_path(dbp, dfh, name, fhrecp, linkp,
947 						errorp);
948 				if (*errorp != 0) {
949 					free(linkp);
950 					return (NULL);
951 				}
952 				return (linkp);
953 			}
954 		} else {
955 			/* new link to a file with a different one already */
956 			len = fill_link_key(LN_NEXT(linkp), &fhrecp->dfh,
957 				fhrecp->name);
958 		}
959 	}
960 	/*
961 	 * prev - link key for the previous link in the list - since we
962 	 * always insert at the front of the list, it's always initially NULL.
963 	 */
964 	linkp->prev_offset = linkp->next_offset + len;	/* aligned */
965 	linkp->reclen = linkp->prev_offset;
966 
967 	/* Add the link information to the database */
968 	linksize = fill_link_key(linkkey, dfh, name);
969 	*errorp = store_record(dbp, linkkey, linksize, linkp, linkp->reclen,
970 			"create_link_struct");
971 	if (*errorp != 0) {
972 		free(linkp);
973 		return (NULL);
974 	}
975 	return (linkp);
976 }
977 
978 /*
979  * db_add_secondary - add secondary record to the database (for the directory
980  * information).
981  * Assumes this is a new link, not yet in the database, and that the primary
982  * record is already in.
983  * If fhrecp is non-null, then fhrecp is the primary record.
984  * Database must be open when this function is called.
985  * Return 0 if success, error code otherwise.
986  */
987 static int
988 db_add_secondary(struct db_list *dbp, fhandle_t *dfh, char *name,
989 	fhandle_t *fh, fhlist_ent *fhrecp)
990 {
991 	int			nextsize, len, error;
992 	linkinfo_ent		nextlink, *newlinkp, *nextlinkp;
993 	uint_t			fhflags;
994 	char			*nextaddr;
995 	fhlist_ent		*new_fhrecp = fhrecp;
996 	fh_primary_key		fhkey;
997 
998 	if (debug > 2)
999 		(void) printf("db_add_secondary entered: name '%s'\n", name);
1000 
1001 	bcopy(&fh->fh_data, fhkey, fh->fh_len);
1002 	if (fhrecp == NULL) {
1003 		/* Fetch the primary record */
1004 		new_fhrecp = fetch_record(dbp, fhkey, fh->fh_len, NULL,
1005 				&error, "db_add_secondary primary");
1006 		if (new_fhrecp == NULL) {
1007 			return (error);
1008 		}
1009 	}
1010 	/* Update fhrec atime if needed */
1011 	error = db_update_fhrec(dbp, fhkey, fh->fh_len, new_fhrecp,
1012 			"db_add_secondary primary");
1013 	fhflags = new_fhrecp->flags;
1014 	/* now create and insert the secondary record */
1015 	newlinkp = create_link_struct(dbp, dfh, name, new_fhrecp, &error);
1016 	if (fhrecp == NULL) {
1017 		free(new_fhrecp);
1018 		new_fhrecp = NULL;
1019 	}
1020 	if (newlinkp == NULL) {
1021 		if (debug > 2)
1022 			(void) printf("create_link_struct '%s' Error %s\n",
1023 				name, ((error >= 0) ? strerror(error) :
1024 					"Unknown"));
1025 		return (error);
1026 	}
1027 	nextsize = LN_NEXT_LEN(newlinkp);
1028 	if (nextsize == 0) {
1029 		/* No next - can exit now */
1030 		if (debug > 2)
1031 			(void) printf("db_add_secondary: no next link\n");
1032 		free(newlinkp);
1033 		return (0);
1034 	}
1035 
1036 	/*
1037 	 * Update the linked list to point to new head: replace head of
1038 	 * list in the primary record, then update previous secondary record
1039 	 * to point to new head
1040 	 */
1041 	new_fhrecp = create_primary_struct(dbp, dfh, name, fh, fhflags,
1042 			new_fhrecp, &error);
1043 	if (new_fhrecp == NULL) {
1044 		if (debug > 2)
1045 			(void) printf(
1046 				"db_add_secondary: replace primary failed\n");
1047 		free(newlinkp);
1048 		return (error);
1049 	} else if (fhrecp == NULL) {
1050 		free(new_fhrecp);
1051 	}
1052 
1053 	/*
1054 	 * newlink is the new head of the list, with its "next" pointing to
1055 	 * the old head, and its "prev" pointing to NULL. We now need to
1056 	 * modify the "next" entry to have its "prev" point to the new entry.
1057 	 */
1058 	nextaddr = LN_NEXT(newlinkp);
1059 	if (debug > 2) {
1060 		debug_print_key(stderr, "db_add_secondary", "next key\n    ",
1061 			nextaddr, nextsize);
1062 	}
1063 	/* Get the next link entry from the database */
1064 	nextlinkp = fetch_record(dbp, nextaddr, nextsize, (void *)&nextlink,
1065 			&error, "db_add_secondary next link");
1066 	if (nextlinkp == NULL) {
1067 		if (debug > 2)
1068 			(void) printf(
1069 				"db_add_secondary: fetch next link failed\n");
1070 		free(newlinkp);
1071 		return (error);
1072 	}
1073 
1074 	/*
1075 	 * since the "prev" field is the only field to be changed, and it's
1076 	 * the last in the link record, we only need to modify it (and reclen).
1077 	 * Re-use link to update the next record.
1078 	 */
1079 	len = fill_link_key(LN_PREV(nextlinkp), dfh, name);
1080 	nextlinkp->reclen = nextlinkp->prev_offset + len;
1081 	error = store_record(dbp, nextaddr, nextsize, nextlinkp,
1082 			nextlinkp->reclen, "db_add_secondary");
1083 	if (debug > 2)
1084 		(void) printf(
1085 			"db_add_secondary exits(%d): name '%s'\n", error, name);
1086 	free(newlinkp);
1087 	return (error);
1088 }
1089 
1090 /*
1091  * Update the next link to point to the new prev.
1092  * Return 0 for success, error code otherwise.
1093  * If successful, and nextlinkpp is non-null,
1094  * *nextlinkpp contains the record for the next link, since
1095  * we may will it if the primary record should be updated.
1096  */
1097 static linkinfo_ent *
1098 update_next_link(struct db_list *dbp, char *nextkey, int nextsize,
1099 	char *prevkey, int prevsize, int *errorp)
1100 {
1101 	linkinfo_ent	*nextlinkp, *linkp1;
1102 
1103 	if ((nextlinkp = malloc(sizeof (linkinfo_ent))) == NULL) {
1104 		*errorp = errno;
1105 		syslog(LOG_ERR, gettext(
1106 			"update_next_link: malloc next Error %s"),
1107 			strerror(*errorp));
1108 		return (NULL);
1109 	}
1110 	linkp1 = nextlinkp;
1111 	nextlinkp = fetch_record(dbp, nextkey, nextsize, nextlinkp,
1112 			errorp, "update next");
1113 	/* if there is no next record - ok */
1114 	if (nextlinkp == NULL) {
1115 		/* Return no error */
1116 		*errorp = 0;
1117 		free(linkp1);
1118 		return (NULL);
1119 	}
1120 	/* Set its prev to the prev of the deleted record */
1121 	nextlinkp->reclen = ROUNDUP32(nextlinkp->reclen -
1122 				LN_PREV_LEN(nextlinkp) + prevsize);
1123 	/* Change the len and set prev */
1124 	if (prevsize > 0) {
1125 		(void) memcpy(LN_PREV(nextlinkp), prevkey, prevsize);
1126 	}
1127 	/* No other changes needed because prev is last field */
1128 	*errorp = store_record(dbp, nextkey, nextsize, nextlinkp,
1129 			nextlinkp->reclen, "update_next");
1130 	if (*errorp != 0) {
1131 		free(nextlinkp);
1132 		nextlinkp = NULL;
1133 	}
1134 	return (nextlinkp);
1135 }
1136 
1137 /*
1138  * Update the prev link to point to the new next.
1139  * Return 0 for success, error code otherwise.
1140  */
1141 static int
1142 update_prev_link(struct db_list *dbp, char *nextkey, int nextsize,
1143 	char *prevkey, int prevsize)
1144 {
1145 	linkinfo_ent	prevlink, *prevlinkp;
1146 	int		diff, error;
1147 
1148 	/* Update its next to the given one */
1149 	prevlinkp = fetch_record(dbp, prevkey, prevsize, &prevlink, &error,
1150 			"update prev");
1151 	/* if error there is no next record - ok */
1152 	if (prevlinkp == NULL) {
1153 		return (0);
1154 	}
1155 	diff = nextsize - LN_NEXT_LEN(prevlinkp);
1156 	prevlinkp->reclen = ROUNDUP32(prevlinkp->reclen + diff);
1157 	/* Change the len and set next - may push prev */
1158 	if (diff != 0) {
1159 		char	*ptr = LN_PREV(prevlinkp);
1160 
1161 		prevlinkp->prev_offset += diff;
1162 		(void) memcpy(LN_PREV(prevlinkp), ptr, LN_PREV_LEN(prevlinkp));
1163 	}
1164 	if (nextsize > 0) {
1165 		(void) memcpy(LN_NEXT(prevlinkp), nextkey, nextsize);
1166 	}
1167 	/* Store updated record */
1168 	error = store_record(dbp, prevkey, prevsize, prevlinkp,
1169 			prevlinkp->reclen, "update_prev");
1170 	return (error);
1171 }
1172 
1173 /*
1174  * update_linked_list - update the next link to point back to prev, and vice
1175  * versa. Normally called by delete_link to drop the deleted link from the
1176  * linked list of hard links for the file. next and prev are the keys of next
1177  * and previous links for the deleted link in the list (could be NULL).
1178  * Return 0 for success, error code otherwise.
1179  * If successful, and nextlinkpp is non-null,
1180  * return the record for the next link, since
1181  * if the primary record should be updated we'll need it. In this case,
1182  * actually allocate the space for it because we can't tell otherwise.
1183  */
1184 static linkinfo_ent *
1185 update_linked_list(struct db_list *dbp, char *nextkey, int nextsize,
1186 	char *prevkey, int prevsize, int *errorp)
1187 {
1188 	linkinfo_ent	*nextlinkp = NULL;
1189 
1190 	*errorp = 0;
1191 	if (nextsize > 0) {
1192 		nextlinkp = update_next_link(dbp, nextkey, nextsize,
1193 				prevkey, prevsize, errorp);
1194 		if (nextlinkp == NULL) {
1195 			/* not an error if no next link */
1196 			if (*errorp != 0) {
1197 				if (debug > 1) {
1198 					(void) fprintf(stderr,
1199 						"update_next_link Error %s\n",
1200 					((*errorp >= 0) ? strerror(*errorp) :
1201 						"Unknown"));
1202 				}
1203 				return (NULL);
1204 			}
1205 		}
1206 	}
1207 	if (prevsize > 0) {
1208 		*errorp = update_prev_link(dbp, nextkey, nextsize,
1209 				prevkey, prevsize);
1210 		if (*errorp != 0) {
1211 			if (debug > 1) {
1212 				(void) fprintf(stderr,
1213 					"update_prev_link Error %s\n",
1214 					((*errorp >= 0) ? strerror(*errorp) :
1215 					"Unknown"));
1216 			}
1217 			if (nextlinkp != NULL)
1218 				free(nextlinkp);
1219 			nextlinkp = NULL;
1220 		}
1221 	}
1222 	return (nextlinkp);
1223 }
1224 
1225 /*
1226  * db_update_primary_new_head - Update a primary record that the head of
1227  * the list is deleted. Similar to db_add_primary, but the primary record
1228  * must exist, and is always replaced with one pointing to the new link,
1229  * unless it does not point to the deleted link. If the link we deleted
1230  * was the last link, the delete the primary record as well.
1231  * Return 0 for success, error code otherwise.
1232  */
1233 static int
1234 db_update_primary_new_head(struct db_list *dbp, linkinfo_ent *dellinkp,
1235 	linkinfo_ent *nextlinkp, fhlist_ent *fhrecp)
1236 {
1237 	int			error;
1238 	char			*name, *next_name;
1239 	fhandle_t		*dfh;
1240 	fh_primary_key		fhkey;
1241 
1242 	dfh = &dellinkp->dfh;
1243 	name = LN_NAME(dellinkp);
1244 	/* If the deleted link was not the head of the list, we are done */
1245 	if (memcmp(&fhrecp->dfh, dfh, sizeof (*dfh)) ||
1246 	    strcmp(fhrecp->name, name)) {
1247 		/* should never be here... */
1248 		if (debug > 1) {
1249 			(void) fprintf(stderr,
1250 				"db_update_primary_new_head: primary "
1251 				"is for [%s,", name);
1252 			debug_opaque_print(stderr, (void *)dfh, sizeof (*dfh));
1253 			(void) fprintf(stderr, "], not [%s,", fhrecp->name);
1254 			debug_opaque_print(stderr, (void *)&fhrecp->dfh,
1255 				sizeof (fhrecp->dfh));
1256 			(void) fprintf(stderr, "]\n");
1257 		}
1258 		return (0);	/* not head of list so done */
1259 	}
1260 	/* Set the head to nextkey if exists. Otherwise, mark file as deleted */
1261 	bcopy(&fhrecp->fh.fh_data, fhkey, fhrecp->fh.fh_len);
1262 	if (nextlinkp == NULL) {
1263 		/* last link */
1264 		/* remove primary record from database */
1265 		(void) delete_record(dbp,
1266 			fhkey, fhrecp->fh.fh_len,
1267 			"db_update_primary_new_head: fh delete");
1268 		return (0);
1269 	} else {
1270 		/*
1271 		 * There are still "live" links, so update the primary record.
1272 		 */
1273 		next_name = LN_NAME(nextlinkp);
1274 		fhrecp->reclen = ROUNDUP32(offsetof(fhlist_ent, name) +
1275 					strlen(next_name) + 1);
1276 		/* Replace link data with the info for the next link */
1277 		(void) memcpy(&fhrecp->dfh, &nextlinkp->dfh,
1278 			sizeof (nextlinkp->dfh));
1279 		(void) strcpy(fhrecp->name, next_name);
1280 	}
1281 	/* not last link */
1282 	fhrecp->mtime = time(0);
1283 	fhrecp->atime = fhrecp->mtime;
1284 	error = store_record(dbp,
1285 			fhkey, fhrecp->fh.fh_len, fhrecp,
1286 			fhrecp->reclen, "db_update_primary_new_head: fh");
1287 	return (error);
1288 }
1289 
1290 /*
1291  * Exported functions
1292  */
1293 
1294 /*
1295  * db_add - add record to the database. If dfh, fh and name are all here,
1296  * add both primary and secondary records. If fh is not available, don't
1297  * add anything...
1298  * Assumes this is a new file, not yet in the database and that the record
1299  * for fh is already in.
1300  * Return 0 for success, error code otherwise.
1301  */
1302 int
1303 db_add(char *fhpath, fhandle_t *dfh, char *name, fhandle_t *fh, uint_t flags)
1304 {
1305 	struct db_list	*dbp = NULL;
1306 	fhlist_ent	fhrec, *fhrecp;
1307 	int		error = 0;
1308 
1309 	if (fh == NULL) {
1310 		/* nothing to add */
1311 		return (EINVAL);
1312 	}
1313 	if (fh == &public_fh) {
1314 		dbp = db_get_all_databases(fhpath, FALSE);
1315 	} else {
1316 		dbp = db_get_db(fhpath, &fh->fh_fsid, &error, O_CREAT);
1317 	}
1318 	for (; dbp != NULL; dbp = ((fh != &public_fh) ? NULL : dbp->next)) {
1319 		if (debug > 3) {
1320 			(void) printf("db_add: name '%s', db '%s'\n",
1321 				name, dbp->path);
1322 		}
1323 		fhrecp = db_add_primary(dbp, dfh, name, fh, flags,
1324 				&fhrec, &error);
1325 		if (fhrecp == NULL) {
1326 			continue;
1327 		}
1328 		if ((dfh == NULL) || (name == NULL)) {
1329 			/* Can't add link information */
1330 			syslog(LOG_ERR, gettext(
1331 				"db_add: dfh %p, name %p - invalid"),
1332 				(void *)dfh, (void *)name);
1333 			error = EINVAL;
1334 			continue;
1335 		}
1336 		if (fh == &public_fh) {
1337 			while ((fhrecp != NULL) && strcmp(name, fhrecp->name)) {
1338 				/* Replace the public fh rather than add link */
1339 				error = db_delete_link(fhpath, dfh,
1340 						fhrecp->name);
1341 				fhrecp = db_add_primary(dbp, dfh, name, fh,
1342 						flags, &fhrec, &error);
1343 			}
1344 			if (fhrecp == NULL) {
1345 				continue;
1346 			}
1347 		}
1348 		error = db_add_secondary(dbp, dfh, name, fh, fhrecp);
1349 		if (fhrecp != &fhrec) {
1350 			free(fhrecp);
1351 		}
1352 	}
1353 	return (error);
1354 }
1355 
1356 /*
1357  * db_lookup - search the database for the file identified by fh.
1358  * Return the entry in *fhrecpp if found, or NULL with error set otherwise.
1359  */
1360 fhlist_ent *
1361 db_lookup(char *fhpath, fhandle_t *fh, fhlist_ent *fhrecp, int *errorp)
1362 {
1363 	struct db_list	*dbp;
1364 	fh_primary_key	fhkey;
1365 
1366 	if ((fhpath == NULL) || (fh == NULL) || (errorp == NULL)) {
1367 		if (errorp != NULL)
1368 			*errorp = EINVAL;
1369 		return (NULL);
1370 	}
1371 	*errorp = 0;
1372 	if (fh == &public_fh) {
1373 		dbp = db_get_all_databases(fhpath, FALSE);
1374 	} else {
1375 		dbp = db_get_db(fhpath, &fh->fh_fsid, errorp, O_CREAT);
1376 	}
1377 	if (dbp == NULL) {
1378 		/* Could not get or create database */
1379 		return (NULL);
1380 	}
1381 	bcopy(&fh->fh_data, fhkey, fh->fh_len);
1382 	fhrecp = fetch_record(dbp, fhkey, fh->fh_len, fhrecp,
1383 			errorp, "db_lookup");
1384 	/* Update fhrec atime if needed */
1385 	if (fhrecp != NULL) {
1386 		*errorp = db_update_fhrec(dbp, fhkey, fh->fh_len, fhrecp,
1387 				"db_lookup");
1388 	}
1389 	return (fhrecp);
1390 }
1391 
1392 /*
1393  * db_lookup_link - search the database for the file identified by (dfh,name).
1394  * If the link was found, use it to search for the primary record.
1395  * Return 0 and set the entry in *fhrecpp if found, return error otherwise.
1396  */
1397 fhlist_ent *
1398 db_lookup_link(char *fhpath, fhandle_t *dfh, char *name, fhlist_ent *fhrecp,
1399 	int *errorp)
1400 {
1401 	struct db_list		*dbp;
1402 	fh_secondary_key	linkkey;
1403 	linkinfo_ent		*linkp;
1404 	int			linksize, fhkeysize;
1405 	char			*fhkey;
1406 
1407 	if ((fhpath == NULL) || (dfh == NULL) || (name == NULL) ||
1408 		(errorp == NULL)) {
1409 		if (errorp != NULL)
1410 			*errorp = EINVAL;
1411 		return (NULL);
1412 	}
1413 	*errorp = 0;
1414 	if (dfh == &public_fh) {
1415 		dbp = db_get_all_databases(fhpath, FALSE);
1416 	} else {
1417 		dbp = db_get_db(fhpath, &dfh->fh_fsid, errorp, O_CREAT);
1418 	}
1419 	if (dbp == NULL) {
1420 		/* Could not get or create database */
1421 		return (NULL);
1422 	}
1423 	/* Get the link record */
1424 	linksize = fill_link_key(linkkey, dfh, name);
1425 	linkp = fetch_record(dbp, linkkey, linksize, NULL, errorp,
1426 			"db_lookup_link link");
1427 	if (linkp != NULL) {
1428 		/* Now use link to search for fh entry */
1429 		fhkeysize = LN_FHKEY_LEN(linkp);
1430 		fhkey = LN_FHKEY(linkp);
1431 		fhrecp = fetch_record(dbp, fhkey, fhkeysize,
1432 				(void *)fhrecp, errorp, "db_lookup_link fh");
1433 		/* Update fhrec atime if needed */
1434 		if (fhrecp != NULL) {
1435 			*errorp = db_update_fhrec(dbp, fhkey, fhkeysize, fhrecp,
1436 				"db_lookup_link fhrec");
1437 		}
1438 		/* Update link atime if needed */
1439 		*errorp = db_update_linkinfo(dbp, linkkey, linksize, linkp,
1440 			"db_lookup_link link");
1441 		free(linkp);
1442 	} else {
1443 		fhrecp = NULL;
1444 	}
1445 	return (fhrecp);
1446 }
1447 
1448 /*
1449  * delete_link - delete the requested link from the database. If it's the
1450  * last link in the database for that file then remove the primary record
1451  * as well. *errorp contains the returned error code.
1452  * Return ENOENT if link not in database and 0 otherwise.
1453  */
1454 static int
1455 delete_link_by_key(struct db_list *dbp, char *linkkey, int *linksizep,
1456 	int *errorp, char *errstr)
1457 {
1458 	int			nextsize, prevsize, fhkeysize, linksize;
1459 	char			*nextkey, *prevkey, *fhkey;
1460 	linkinfo_ent		*dellinkp, *nextlinkp;
1461 	fhlist_ent		*fhrecp, fhrec;
1462 
1463 	*errorp = 0;
1464 	linksize = *linksizep;
1465 	/* Get the link record */
1466 	dellinkp = fetch_record(dbp, linkkey, linksize, NULL, errorp, errstr);
1467 	if (dellinkp == NULL) {
1468 		/*
1469 		 * Link not in database.
1470 		 */
1471 		if (debug > 2) {
1472 			debug_print_key(stderr, errstr,
1473 				"link not in database\n",
1474 				linkkey, linksize);
1475 		}
1476 		*linksizep = 0;
1477 		return (ENOENT);
1478 	}
1479 	/*
1480 	 * Possibilities:
1481 	 * 1. Normal case - only one link to delete: the link next and
1482 	 *    prev should be NULL, and fhrec's name/dfh are same
1483 	 *    as the link. Remove the link and fhrec.
1484 	 * 2. Multiple hard links, and the deleted link is the head of
1485 	 *    the list. Remove the link and replace the link key in
1486 	 *    the primary record to point to the new head.
1487 	 * 3. Multiple hard links, and the deleted link is not the
1488 	 *    head of the list (not the same as in fhrec) - just
1489 	 *    delete the link and update the previous and next records
1490 	 *    in the links linked list.
1491 	 */
1492 
1493 	/* Get next and prev keys for linked list updates */
1494 	nextsize = LN_NEXT_LEN(dellinkp);
1495 	nextkey = ((nextsize > 0) ? LN_NEXT(dellinkp) : NULL);
1496 	prevsize = LN_PREV_LEN(dellinkp);
1497 	prevkey = ((prevsize > 0) ? LN_PREV(dellinkp) : NULL);
1498 	/* Update the linked list for the file */
1499 	nextlinkp = update_linked_list(dbp, nextkey, nextsize,
1500 			prevkey, prevsize, errorp);
1501 	if ((nextlinkp == NULL) && (*errorp != 0)) {
1502 		free(dellinkp);
1503 		*linksizep = 0;
1504 		return (0);
1505 	}
1506 	/* Delete link record */
1507 	*errorp = delete_record(dbp, linkkey, linksize, errstr);
1508 	/* Get the primary key */
1509 	fhkeysize = LN_FHKEY_LEN(dellinkp);
1510 	fhkey = LN_FHKEY(dellinkp);
1511 	fhrecp = fetch_record(dbp, fhkey, fhkeysize,
1512 		&fhrec, errorp, errstr);
1513 	if (fhrecp == NULL) {
1514 		/* Should never happen */
1515 		if (debug > 1) {
1516 			debug_print_key(stderr, errstr,
1517 				"fetch primary for ", linkkey, linksize);
1518 			(void) fprintf(stderr, " Error %s\n",
1519 			((*errorp >= 0) ? strerror(*errorp) : "Unknown"));
1520 		}
1521 	} else if ((*errorp == 0) && (prevsize <= 0)) {
1522 		/* This is the head of the list update primary record */
1523 		*errorp = db_update_primary_new_head(dbp, dellinkp,
1524 				nextlinkp, fhrecp);
1525 	} else {
1526 		/* Update fhrec atime if needed */
1527 		*errorp = db_update_fhrec(dbp, fhkey, fhkeysize, fhrecp,
1528 				errstr);
1529 	}
1530 	*linksizep = nextsize;
1531 	if (nextsize > 0)
1532 		(void) memcpy(linkkey, nextkey, nextsize);
1533 	if (nextlinkp != NULL)
1534 		free(nextlinkp);
1535 	free(dellinkp);
1536 	return (0);
1537 }
1538 
1539 /*
1540  * delete_link - delete the requested link from the database. If it's the
1541  * last link in the database for that file then remove the primary record
1542  * as well. If nextlinkkey/sizep are non-null, copy the key and key size of
1543  * the next link in the chain into them (this would save a dbm_fetch op).
1544  * Return ENOENT if link not in database and 0 otherwise, with *errorp
1545  * containing the returned error if any from the delete_link ops.
1546  */
1547 static int
1548 delete_link(struct db_list *dbp, fhandle_t *dfh, char *name,
1549 	char *nextlinkkey, int *nextlinksizep, int *errorp, char *errstr)
1550 {
1551 	int	linkerr;
1552 
1553 	*errorp = 0;
1554 	if ((nextlinkkey != NULL) && (nextlinksizep != NULL)) {
1555 		*nextlinksizep = fill_link_key(nextlinkkey, dfh, name);
1556 		linkerr = delete_link_by_key(dbp, nextlinkkey, nextlinksizep,
1557 				errorp, errstr);
1558 	} else {
1559 		int			linksize;
1560 		fh_secondary_key	linkkey;
1561 
1562 		linksize = fill_link_key(linkkey, dfh, name);
1563 		linkerr = delete_link_by_key(dbp, linkkey, &linksize,
1564 				errorp, errstr);
1565 	}
1566 	return (linkerr);
1567 }
1568 
1569 /*
1570  * db_delete_link - search the database for the file system for link.
1571  * Delete the link from the database. If this is the "primary" link,
1572  * set the primary record for the next link. If it's the last one,
1573  * delete the primary record.
1574  * Return 0 for success, error code otherwise.
1575  */
1576 int
1577 db_delete_link(char *fhpath, fhandle_t *dfh, char *name)
1578 {
1579 	struct db_list		*dbp;
1580 	int			error = 0;
1581 
1582 	if ((fhpath == NULL) || (dfh == NULL) || (name == NULL)) {
1583 		return (EINVAL);
1584 	}
1585 	if (dfh == &public_fh) {
1586 		dbp = db_get_all_databases(fhpath, TRUE);
1587 	} else {
1588 		dbp = db_get_db(fhpath, &dfh->fh_fsid, &error, O_CREAT);
1589 	}
1590 	for (; dbp != NULL; dbp = ((dfh == &public_fh) ? dbp->next : NULL)) {
1591 		(void) delete_link(dbp, dfh, name, NULL, NULL, &error,
1592 			"db_delete_link link");
1593 	}
1594 	return (error);
1595 }
1596 
1597 #ifdef DEBUG
1598 /*
1599  * db_delete - Deletes the fhrec corresponding to the fh. Use only
1600  * for repairing the fhtable, not for normal handling.
1601  * Return 0 for success, error code otherwise.
1602  */
1603 int
1604 db_delete(char *fhpath, fhandle_t *fh)
1605 {
1606 	struct db_list		*dbp;
1607 	int			error = 0;
1608 
1609 	if ((fhpath == NULL) || (fh == NULL)) {
1610 		return (EINVAL);
1611 	}
1612 	if (fh == &public_fh) {
1613 		dbp = db_get_all_databases(fhpath, TRUE);
1614 	} else {
1615 		dbp = db_get_db(fhpath, &fh->fh_fsid, &error, O_CREAT);
1616 	}
1617 	for (; dbp != NULL; dbp = ((fh == &public_fh) ? dbp->next : NULL)) {
1618 		/* Get the link record */
1619 		(void) delete_record(dbp, &fh->fh_data, fh->fh_len,
1620 			"db_delete: fh delete");
1621 	}
1622 	return (error);
1623 }
1624 #endif  /* DEBUG */
1625 
1626 /*
1627  * db_rename_link - search the database for the file system for link.
1628  * Add the new link and delete the old link from the database.
1629  * Return 0 for success, error code otherwise.
1630  */
1631 int
1632 db_rename_link(char *fhpath, fhandle_t *from_dfh, char *from_name,
1633 	fhandle_t *to_dfh, char *to_name)
1634 {
1635 	int			error;
1636 	struct db_list		*dbp;
1637 	fhlist_ent		fhrec, *fhrecp;
1638 
1639 	if ((fhpath == NULL) || (from_dfh == NULL) || (from_name == NULL) ||
1640 		(to_dfh == NULL) || (to_name == NULL)) {
1641 		return (EINVAL);
1642 	}
1643 	if (from_dfh == &public_fh) {
1644 		dbp = db_get_all_databases(fhpath, FALSE);
1645 	} else {
1646 		dbp = db_get_db(fhpath, &from_dfh->fh_fsid, &error, O_CREAT);
1647 	}
1648 	for (; dbp != NULL;
1649 		dbp = ((from_dfh != &public_fh) ? NULL : dbp->next)) {
1650 		/* find existing link */
1651 		fhrecp = db_lookup_link(fhpath, from_dfh, from_name, &fhrec,
1652 				&error);
1653 		if (fhrecp == NULL) {
1654 			/* Could not find the link */
1655 			continue;
1656 		}
1657 		/* Delete the old link (if last primary record not deleted) */
1658 		error = db_delete_link(fhpath, from_dfh, from_name);
1659 		if (error == 0) {
1660 			error = db_add(fhpath, to_dfh, to_name, &fhrecp->fh,
1661 					fhrecp->flags);
1662 		}
1663 	}
1664 	return (error);
1665 }
1666 
1667 /*
1668  * db_print_all_keys: prints all keys for a given filesystem. If fsidp is
1669  * NULL, print for all filesystems covered by fhpath.
1670  */
1671 void
1672 db_print_all_keys(char *fhpath, fsid_t *fsidp, FILE *fp)
1673 {
1674 	struct db_list	*dbp;
1675 	datum		key;
1676 	int		error, len;
1677 	char		strkey[NFS_FHMAXDATA + MAXNAMELEN];
1678 	db_record	rec;
1679 	void		*ptr;
1680 
1681 	if ((fhpath == NULL) ||
1682 	    ((fsidp != NULL) && (fsidp == &public_fh.fh_fsid)))
1683 		return;
1684 	if (fsidp == NULL) {
1685 		(void) db_get_all_databases(fhpath, TRUE);
1686 		dbp = db_fs_list;
1687 	} else {
1688 		dbp = db_get_db(fhpath, fsidp, &error, 0);
1689 	}
1690 	if (dbp == NULL) {
1691 		/* Could not get or create database */
1692 		return;
1693 	}
1694 	len = strlen(fhpath);
1695 	for (; dbp != NULL; dbp = ((fsidp != NULL) ? NULL : dbp->next)) {
1696 		if (strncmp(fhpath, dbp->path, len))
1697 			continue;
1698 		(void) fprintf(fp,
1699 			"\nStart print database for fsid 0x%x 0x%x\n",
1700 			dbp->fsid.val[0], dbp->fsid.val[1]);
1701 		(void) fprintf(fp, "=============================\n");
1702 		for (key = dbm_firstkey(dbp->db); key.dptr != NULL;
1703 			key = dbm_nextkey(dbp->db)) {
1704 			(void) memcpy(strkey, key.dptr, key.dsize);
1705 			debug_print_key(fp, "", "", strkey, key.dsize);
1706 			if (debug < 2)
1707 				continue;
1708 			ptr = fetch_record(dbp, key.dptr, key.dsize,
1709 					(void *)&rec, &error, "db_prt_keys");
1710 			if (ptr == NULL)
1711 				continue;
1712 			if (key.dsize == NFS_FHMAXDATA) {
1713 				/* fhrec */
1714 				debug_print_fhlist(fp, &rec.fhlist_rec);
1715 			} else if (key.dsize > NFS_FHMAXDATA) {
1716 				/* linkinfo */
1717 				debug_print_linkinfo(fp, &rec.link_rec);
1718 			}
1719 			(void) fprintf(fp, "-----------------------------\n");
1720 		}
1721 		(void) fprintf(fp, "End print database for fsid 0x%x 0x%x\n",
1722 			dbp->fsid.val[0], dbp->fsid.val[1]);
1723 	}
1724 }
1725 
1726 void
1727 debug_opaque_print(FILE *fp, void *buf, int size)
1728 {
1729 	int		bufoffset = 0;
1730 	char		debug_str[200];
1731 
1732 	if ((buf == NULL) || (size <= 0))
1733 		return;
1734 
1735 	nfslog_opaque_print_buf(buf, size, debug_str, &bufoffset, 200);
1736 	(void) fprintf(fp, debug_str);
1737 }
1738 
1739 /*
1740  * links_timedout() takes a primary records and searches all of its
1741  * links to see if they all have access times that are older than
1742  * the 'prune_timeout' value.  TRUE if all links are old and FALSE
1743  * if there is just one link that has an access time which is recent.
1744  */
1745 static int
1746 links_timedout(struct db_list *pdb, fhlist_ent *pfe, time_t ts)
1747 {
1748 	fh_secondary_key	linkkey;
1749 	linkinfo_ent		*linkp, link_st;
1750 	int			error;
1751 	int			linksize;
1752 	void			*cookie;
1753 
1754 	/* Get the link record */
1755 	linksize = fill_link_key(linkkey, &pfe->dfh, pfe->name);
1756 	cookie = NULL;
1757 	do {
1758 		linkp = get_next_link(pdb, linkkey, &linksize, &link_st,
1759 				&cookie, &error, "links_timedout");
1760 		if ((linkp != NULL) &&
1761 			(difftime(ts, linkp->atime) <= prune_timeout)) {
1762 			/* update primary record to have an uptodate time */
1763 			pfe = fetch_record(pdb, (void *)&pfe->fh.fh_data,
1764 					pfe->fh.fh_len, NULL, &error,
1765 					"links_timedout");
1766 			if (pfe == NULL) {
1767 				syslog(LOG_ERR, gettext(
1768 				"links_timedout: fetch fhrec error %s\n"),
1769 				strerror(error));
1770 			} else {
1771 				if (difftime(pfe->atime, linkp->atime) < 0) {
1772 					/* update fhrec atime */
1773 					pfe->atime = linkp->atime;
1774 					(void) store_record(pdb,
1775 						(void *)&pfe->fh.fh_data,
1776 						pfe->fh.fh_len, pfe,
1777 						pfe->reclen, "links_timedout");
1778 				}
1779 				free(pfe);
1780 			}
1781 			free_link_cookies(cookie);
1782 			return (FALSE);
1783 		}
1784 	} while (linksize > 0);
1785 
1786 	free_link_cookies(cookie);
1787 	return (TRUE);
1788 }
1789 
1790 /*
1791  * prune_dbs() will search all of the open databases looking for records
1792  * that have not been accessed in the last 'prune_timeout' seconds.
1793  * This search is done on the primary records and a list of potential
1794  * timeout candidates is built.  The reason for doing this is to not
1795  * disturb the underlying dbm_firstkey()/dbm_nextkey() sequence; we
1796  * want to search all of the records in the database.
1797  * Once we have our candidate list built, we examine each of those
1798  * item's links to check if the links have been accessed within the
1799  * 'prune_timeout' seconds.  If neither the primary nor any its links
1800  * have been accessed, then all of those records are removed/deleted
1801  * from the database.
1802  */
1803 int
1804 prune_dbs(char *fhpath)
1805 {
1806 	struct db_list		*pdb;
1807 	datum			key;
1808 	db_record		*ptr;
1809 	struct fhlist_ent 	*pfe;
1810 	int			error, linkerr, linksize;
1811 	time_t			cur_time = time(0);
1812 	fh_secondary_key	linkkey;
1813 	struct thelist {
1814 		struct thelist *next;
1815 		db_record *ptr;
1816 	} 			thelist, *ptl;
1817 	int	cnt = 0;
1818 
1819 	if (fhpath != NULL)
1820 		(void) db_get_all_databases(fhpath, TRUE);
1821 
1822 	thelist.next = NULL;
1823 	/*
1824 	 * Search each of the open databases
1825 	 */
1826 	for (pdb = db_fs_list; pdb; pdb = pdb->next) {
1827 	    do {
1828 		/* Check each record in the database */
1829 		for (key = dbm_firstkey(pdb->db); key.dptr != NULL;
1830 		    key = dbm_nextkey(pdb->db)) {
1831 			/* We're only interested in primary records */
1832 			if (key.dsize != NFS_FHMAXDATA)
1833 				continue;	/* probably a link record */
1834 			ptr = fetch_record(pdb, key.dptr, key.dsize,
1835 					NULL, &error, "dump_db");
1836 			if (ptr == NULL)
1837 				continue;
1838 			/*
1839 			 * If this record is a primary record and it is
1840 			 * not an export point or a public file handle path,
1841 			 * check it for a ancient access time.
1842 			 */
1843 			if ((ptr->fhlist_rec.flags &
1844 				    (EXPORT_POINT | PUBLIC_PATH)) ||
1845 			    (difftime(cur_time, ptr->fhlist_rec.atime) <=
1846 					prune_timeout)) {
1847 				/* Keep this record in the database */
1848 				free(ptr);
1849 			} else {
1850 				/* Found one?  Save off info about it */
1851 				ptl = malloc(sizeof (struct thelist));
1852 				if (ptl == NULL) {
1853 					syslog(LOG_ERR, gettext(
1854 				"prune_dbs: malloc failed, error %s\n"),
1855 						strerror(errno));
1856 					break;
1857 				}
1858 				ptl->ptr = ptr;
1859 				ptl->next = thelist.next;
1860 				thelist.next = ptl;
1861 				cnt++;	/* count how many records allocated */
1862 				if (cnt > MAX_PRUNE_REC_CNT) {
1863 					/* Limit number of records malloc'd */
1864 					if (debug)
1865 						(void) fprintf(stderr,
1866 				"prune_dbs: halt search - too many records\n");
1867 					break;
1868 				}
1869 			}
1870 		}
1871 
1872 		/*
1873 		 * Take the saved records and check their links to make
1874 		 * sure that they have not been accessed as well.
1875 		 */
1876 		for (ptl = thelist.next; ptl; ptl = thelist.next) {
1877 			thelist.next = ptl->next;
1878 			/* Everything timed out? */
1879 			pfe = &(ptl->ptr->fhlist_rec);
1880 			if (links_timedout(pdb,	pfe, cur_time)) {
1881 
1882 				/*
1883 				 * Iterate until we run out of links.
1884 				 * We have to do this since there can be
1885 				 * multiple links to a primary record and
1886 				 * we need to delete one at a time.
1887 				 */
1888 				/* Delete the link and get the next */
1889 				linkerr = delete_link(pdb,
1890 						&pfe->dfh, pfe->name, linkkey,
1891 						&linksize, &error, "dump_db");
1892 				while ((linksize > 0) && !(error || linkerr)) {
1893 					/* Delete the link and get the next */
1894 					linkerr = delete_link_by_key(pdb,
1895 						linkkey, &linksize,
1896 						&error, "dump_db");
1897 					if (error || linkerr) {
1898 						break;
1899 					}
1900 				}
1901 				if (linkerr) {
1902 					/* link not in database, primary is */
1903 					/* Should never happen */
1904 					if (debug > 1) {
1905 						(void) fprintf(stderr,
1906 					"prune_dbs: Error primary exists ");
1907 						debug_opaque_print(stderr,
1908 							(void *)&pfe->fh,
1909 							sizeof (pfe->fh));
1910 						(void) fprintf(stderr, "\n");
1911 					}
1912 					if (debug)
1913 						syslog(LOG_ERR, gettext(
1914 					"prune_dbs: Error primary exists\n"));
1915 					(void) delete_record(pdb,
1916 					&pfe->fh.fh_data, pfe->fh.fh_len,
1917 					"prune_dbs: fh delete");
1918 				}
1919 			}
1920 			/* Make sure to free the pointers used in the list */
1921 			free(ptl->ptr);
1922 			free(ptl);
1923 			cnt--;
1924 		}
1925 		thelist.next = NULL;
1926 	    } while (key.dptr != NULL);
1927 	}
1928 	return (0);
1929 }
1930