xref: /illumos-gate/usr/src/lib/fm/libfmd_log/common/fmd_log.c (revision 826ac02a0def83e0a41b29321470d299c7389aab)
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 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/fm/protocol.h>
27 #include <sys/types.h>
28 #include <sys/mkdev.h>
29 
30 #include <alloca.h>
31 #include <unistd.h>
32 #include <limits.h>
33 #include <strings.h>
34 #include <stdlib.h>
35 #include <fcntl.h>
36 #include <errno.h>
37 #include <libgen.h>
38 #include <dirent.h>
39 #include <fmd_log_impl.h>
40 #include <fmd_log.h>
41 
42 #define	CAT_FMA_RGROUP	(EXT_GROUP | EXC_DEFAULT | EXD_GROUP_RFMA)
43 #define	CAT_FMA_GROUP	(EXT_GROUP | EXC_DEFAULT | EXD_GROUP_FMA)
44 
45 #define	CAT_FMA_LABEL	(EXT_STRING | EXC_DEFAULT | EXD_FMA_LABEL)
46 #define	CAT_FMA_VERSION	(EXT_STRING | EXC_DEFAULT | EXD_FMA_VERSION)
47 #define	CAT_FMA_OSREL	(EXT_STRING | EXC_DEFAULT | EXD_FMA_OSREL)
48 #define	CAT_FMA_OSVER	(EXT_STRING | EXC_DEFAULT | EXD_FMA_OSVER)
49 #define	CAT_FMA_PLAT	(EXT_STRING | EXC_DEFAULT | EXD_FMA_PLAT)
50 #define	CAT_FMA_UUID	(EXT_STRING | EXC_DEFAULT | EXD_FMA_UUID)
51 #define	CAT_FMA_TODSEC	(EXT_UINT64 | EXC_DEFAULT | EXD_FMA_TODSEC)
52 #define	CAT_FMA_TODNSEC	(EXT_UINT64 | EXC_DEFAULT | EXD_FMA_TODNSEC)
53 #define	CAT_FMA_NVLIST	(EXT_RAW | EXC_DEFAULT | EXD_FMA_NVLIST)
54 #define	CAT_FMA_MAJOR	(EXT_UINT32 | EXC_DEFAULT | EXD_FMA_MAJOR)
55 #define	CAT_FMA_MINOR	(EXT_UINT32 | EXC_DEFAULT | EXD_FMA_MINOR)
56 #define	CAT_FMA_INODE	(EXT_UINT64 | EXC_DEFAULT | EXD_FMA_INODE)
57 #define	CAT_FMA_OFFSET	(EXT_UINT64 | EXC_DEFAULT | EXD_FMA_OFFSET)
58 
59 static int fmd_log_load_record(fmd_log_t *, uint_t, fmd_log_record_t *);
60 static void fmd_log_free_record(fmd_log_record_t *);
61 static int fmd_log_load_xrefs(fmd_log_t *, uint_t, fmd_log_record_t *);
62 
63 static const char FMD_CREATOR[] = "fmd";
64 
65 /*
66  * fmd_log_set_errno is used as a utility function throughout the library.  It
67  * sets both lp->log_errno and errno to the specified value.  If the current
68  * error is EFDL_EXACCT, we store it internally as that value plus ea_error().
69  * If no ea_error() is present, we assume EFDL_BADTAG (catalog tag mismatch).
70  */
71 static int
72 fmd_log_set_errno(fmd_log_t *lp, int err)
73 {
74 	if (err == EFDL_EXACCT && ea_error() != EXR_OK)
75 		lp->log_errno = EFDL_EXACCT + ea_error();
76 	else if (err == EFDL_EXACCT)
77 		lp->log_errno = EFDL_BADTAG;
78 	else
79 		lp->log_errno = err;
80 
81 	errno = lp->log_errno;
82 	return (-1);
83 }
84 
85 /*PRINTFLIKE2*/
86 static void
87 fmd_log_dprintf(fmd_log_t *lp, const char *format, ...)
88 {
89 	va_list ap;
90 
91 	if (lp->log_flags & FMD_LF_DEBUG) {
92 		(void) fputs("fmd_log DEBUG: ", stderr);
93 		va_start(ap, format);
94 		(void) vfprintf(stderr, format, ap);
95 		va_end(ap);
96 	}
97 }
98 
99 /*
100  * fmd_log_load_record() is used to load the exacct object at the current file
101  * location into the specified fmd_log_record structure.  Once the caller has
102  * made use of this information, it can clean up using fmd_log_free_record().
103  */
104 static int
105 fmd_log_load_record(fmd_log_t *lp, uint_t iflags, fmd_log_record_t *rp)
106 {
107 	ea_object_t *grp, *obj;
108 	off64_t off;
109 	int err;
110 
111 	if (iflags & FMD_LOG_XITER_OFFS) {
112 		ea_clear(&lp->log_ea);
113 		off = lseek64(lp->log_fd, 0, SEEK_CUR);
114 	}
115 
116 	if ((grp = ea_get_object_tree(&lp->log_ea, 1)) == NULL)
117 		return (fmd_log_set_errno(lp, EFDL_EXACCT));
118 
119 	if (grp->eo_catalog != CAT_FMA_RGROUP &&
120 	    grp->eo_catalog != CAT_FMA_GROUP) {
121 		fmd_log_dprintf(lp, "bad catalog tag 0x%x\n", grp->eo_catalog);
122 		ea_free_object(grp, EUP_ALLOC);
123 		return (fmd_log_set_errno(lp, EFDL_EXACCT));
124 	}
125 
126 	bzero(rp, sizeof (fmd_log_record_t));
127 	rp->rec_grp = grp;
128 
129 	if (iflags & FMD_LOG_XITER_OFFS)
130 		rp->rec_off = off;
131 
132 	for (obj = grp->eo_group.eg_objs; obj != NULL; obj = obj->eo_next) {
133 		switch (obj->eo_catalog) {
134 		case CAT_FMA_NVLIST:
135 			if ((err = nvlist_unpack(obj->eo_item.ei_raw,
136 			    obj->eo_item.ei_size, &rp->rec_nvl, 0)) != 0) {
137 				fmd_log_free_record(rp);
138 				return (fmd_log_set_errno(lp, err));
139 			}
140 			break;
141 
142 		case CAT_FMA_TODSEC:
143 			rp->rec_sec = obj->eo_item.ei_uint64;
144 			break;
145 
146 		case CAT_FMA_TODNSEC:
147 			rp->rec_nsec = obj->eo_item.ei_uint64;
148 			break;
149 
150 		case CAT_FMA_GROUP:
151 			rp->rec_nrefs += obj->eo_group.eg_nobjs;
152 			break;
153 		}
154 	}
155 
156 	if (rp->rec_nvl == NULL || nvlist_lookup_string(rp->rec_nvl,
157 	    FM_CLASS, (char **)&rp->rec_class) != 0) {
158 		fmd_log_free_record(rp);
159 		return (fmd_log_set_errno(lp, EFDL_NOCLASS));
160 	}
161 
162 	if (rp->rec_nrefs != 0 && fmd_log_load_xrefs(lp, iflags, rp) != 0) {
163 		err = errno; /* errno is set for us */
164 		fmd_log_free_record(rp);
165 		return (fmd_log_set_errno(lp, err));
166 	}
167 
168 	return (0);
169 }
170 
171 /*
172  * fmd_log_free_record frees memory associated with the specified record.  If
173  * cross-references are contained in this record, we proceed recursively.
174  */
175 static void
176 fmd_log_free_record(fmd_log_record_t *rp)
177 {
178 	uint_t i;
179 
180 	if (rp->rec_xrefs != NULL) {
181 		for (i = 0; i < rp->rec_nrefs; i++)
182 			fmd_log_free_record(&rp->rec_xrefs[i]);
183 		free(rp->rec_xrefs);
184 	}
185 
186 	nvlist_free(rp->rec_nvl);
187 	ea_free_object(rp->rec_grp, EUP_ALLOC);
188 }
189 
190 /*
191  * fmd_log_load_xref loads the cross-reference represented by the specified
192  * exacct group 'grp' into the next empty slot in rp->rec_xrefs.  This function
193  * is called repeatedly by fmd_log_load_xrefs() for each embedded reference.
194  */
195 static int
196 fmd_log_load_xref(fmd_log_t *lp, uint_t iflags,
197     fmd_log_record_t *rp, ea_object_t *grp)
198 {
199 	ea_object_t *obj;
200 	fmd_log_t *xlp;
201 	dev_t dev;
202 
203 	off64_t off = (off64_t)-1L;
204 	major_t maj = (major_t)-1L;
205 	minor_t min = (minor_t)-1L;
206 	ino64_t ino = (ino64_t)-1L;
207 	char *uuid = NULL;
208 
209 	for (obj = grp->eo_group.eg_objs; obj != NULL; obj = obj->eo_next) {
210 		switch (obj->eo_catalog) {
211 		case CAT_FMA_MAJOR:
212 			maj = obj->eo_item.ei_uint32;
213 			break;
214 		case CAT_FMA_MINOR:
215 			min = obj->eo_item.ei_uint32;
216 			break;
217 		case CAT_FMA_INODE:
218 			ino = obj->eo_item.ei_uint64;
219 			break;
220 		case CAT_FMA_OFFSET:
221 			off = obj->eo_item.ei_uint64;
222 			break;
223 		case CAT_FMA_UUID:
224 			uuid = obj->eo_item.ei_string;
225 			break;
226 		}
227 	}
228 
229 	if (off == (off64_t)-1L || (uuid == NULL && (ino == (ino64_t)-1L ||
230 	    maj == (major_t)-1L || min == (minor_t)-1L)))
231 		return (fmd_log_set_errno(lp, EFDL_BADREF));
232 
233 	if (uuid == NULL && (dev = makedev(maj, min)) == NODEV)
234 		return (fmd_log_set_errno(lp, EFDL_BADDEV));
235 
236 	/*
237 	 * Search our xref list for matching (dev_t, ino64_t) or (uuid).
238 	 * If we can't find one, return silently without
239 	 * doing anything.  We expect log xrefs to be broken whenever log
240 	 * files are trimmed or removed; their only purpose is to help us
241 	 * debug diagnosis engine algorithms.
242 	 */
243 	for (xlp = lp->log_xrefs; xlp != NULL; xlp = xlp->log_xnext) {
244 		if (uuid == NULL) {
245 			if (xlp->log_stat.st_ino == ino &&
246 			    xlp->log_stat.st_dev == dev)
247 				break;
248 		} else if (xlp->log_uuid != NULL &&
249 		    strcmp(xlp->log_uuid, uuid) == 0)
250 			break;
251 	}
252 
253 	if (xlp == NULL) {
254 		if (uuid == NULL)
255 			fmd_log_dprintf(lp, "broken xref dev=%lx ino=%llx\n",
256 			    (ulong_t)dev, (u_longlong_t)ino);
257 		else
258 			fmd_log_dprintf(lp, "broken xref uuid=%s\n", uuid);
259 
260 		return (0);
261 	}
262 
263 	xlp->log_flags &= ~FMD_LF_START;
264 	ea_clear(&xlp->log_ea);
265 	(void) lseek64(xlp->log_fd, off, SEEK_SET);
266 
267 	return (fmd_log_load_record(xlp,
268 	    iflags, &rp->rec_xrefs[rp->rec_nrefs++]));
269 }
270 
271 /*
272  * fmd_log_load_xrdir is called by fmd_log_load_xrefs when the FMD_LF_XREFS bit
273  * is not yet set, indicating we haven't looked for cross-referenced files.  We
274  * open the directory associated with the specified log file and attempt to
275  * perform an fmd_log_open() on every file found there (i.e. /var/fm/fmd).  If
276  * we are successful, the files are chained on to lp->log_xrefs, where the
277  * fmd_log_load_xref() function can find them by comparing dev/ino to log_stat.
278  */
279 static void
280 fmd_log_load_xrdir(fmd_log_t *lp)
281 {
282 	fmd_log_t *xlp;
283 	char dirbuf[PATH_MAX], path[PATH_MAX], *dirpath;
284 	struct dirent *dp;
285 	DIR *dirp;
286 	struct stat statbuf;
287 
288 	lp->log_flags |= FMD_LF_XREFS;
289 	(void) strlcpy(dirbuf, lp->log_path, sizeof (dirbuf));
290 	dirpath = dirname(dirbuf);
291 
292 	if ((dirp = opendir(dirpath)) == NULL)
293 		return; /* failed to open directory; just skip it */
294 
295 	while ((dp = readdir(dirp)) != NULL) {
296 		if (dp->d_name[0] == '.')
297 			continue; /* skip "." and ".." and hidden files */
298 
299 		(void) snprintf(path, sizeof (path),
300 		    "%s/%s", dirpath, dp->d_name);
301 
302 		if (strcmp(path, lp->log_path) != 0 &&
303 		    stat(path, &statbuf) != -1 &&
304 		    (statbuf.st_mode & S_IFMT) == S_IFREG &&
305 		    (xlp = fmd_log_open(lp->log_abi, path, NULL)) != NULL) {
306 			fmd_log_dprintf(lp, "%s loaded %s for xrefs\n",
307 			    lp->log_path, xlp->log_path);
308 			xlp->log_xnext = lp->log_xrefs;
309 			lp->log_xrefs = xlp;
310 		}
311 	}
312 }
313 
314 /*
315  * fmd_log_load_xrefs iterates again over the record's exacct group and for
316  * each cross-reference (embedded CAT_FMA_GROUP), attempts to fill in the
317  * corresponding xref.  rp->rec_nrefs is reset to the number of valid items
318  * in the finished rp->rec_xrefs array; see fmd_log_load_xref() for more info.
319  */
320 static int
321 fmd_log_load_xrefs(fmd_log_t *lp, uint_t iflags, fmd_log_record_t *rp)
322 {
323 	size_t size = sizeof (fmd_log_record_t) * rp->rec_nrefs;
324 	ea_object_t *rgrp = rp->rec_grp;
325 	ea_object_t *grp, *obj;
326 
327 	if (!(iflags & FMD_LOG_XITER_REFS))
328 		return (0); /* do not load any xrefs */
329 
330 	if (!(lp->log_flags & FMD_LF_XREFS))
331 		fmd_log_load_xrdir(lp);
332 
333 	if ((rp->rec_xrefs = malloc(size)) == NULL)
334 		return (fmd_log_set_errno(lp, EFDL_NOMEM));
335 
336 	bzero(rp->rec_xrefs, size);
337 	rp->rec_nrefs = 0;
338 
339 	/*
340 	 * Make a second pass through the record group to locate and process
341 	 * each cross-reference sub-group.  The structure of the groups is
342 	 * as follows (left-hand-side symbols named after the variables used):
343 	 *
344 	 * rgrp := CAT_FMA_TODSEC CAT_FMA_TODNSEC CAT_FMA_NVLIST grp*
345 	 * grp  := obj* (i.e. zero or more groups of xref items)
346 	 * obj  := CAT_FMA_MAJOR CAT_FMA_MINOR CAT_FMA_INODE CAT_FMA_OFFSET
347 	 *
348 	 * For each xref 'obj', we call fmd_log_load_xref() to parse the four
349 	 * xref members and then load the specified record into rp->rec_xrefs.
350 	 */
351 	for (grp = rgrp->eo_group.eg_objs; grp != NULL; grp = grp->eo_next) {
352 		if (grp->eo_catalog != CAT_FMA_GROUP)
353 			continue; /* ignore anything that isn't a group */
354 
355 		for (obj = grp->eo_group.eg_objs;
356 		    obj != NULL; obj = obj->eo_next) {
357 			if (fmd_log_load_xref(lp, iflags, rp, obj) != 0)
358 				return (-1); /* errno is set for us */
359 		}
360 	}
361 
362 	return (0);
363 }
364 
365 static fmd_log_t *
366 fmd_log_open_err(fmd_log_t *lp, int *errp, int err)
367 {
368 	if (errp != NULL)
369 		*errp = err == EFDL_EXACCT ? EFDL_EXACCT + ea_error() : err;
370 
371 	if (lp != NULL)
372 		fmd_log_close(lp);
373 
374 	return (NULL);
375 }
376 
377 fmd_log_t *
378 fmd_log_open(int abi, const char *name, int *errp)
379 {
380 	ea_object_t *grp, *obj;
381 	fmd_log_t *lp;
382 	int fd;
383 
384 	if (abi > FMD_LOG_VERSION)
385 		return (fmd_log_open_err(NULL, errp, EFDL_VERSION));
386 
387 	if ((lp = malloc(sizeof (fmd_log_t))) == NULL)
388 		return (fmd_log_open_err(NULL, errp, EFDL_NOMEM));
389 
390 	bzero(lp, sizeof (fmd_log_t));
391 
392 	if ((lp->log_path = strdup(name)) == NULL)
393 		return (fmd_log_open_err(lp, errp, EFDL_NOMEM));
394 
395 	if ((lp->log_fd = open64(name, O_RDONLY)) == -1 ||
396 	    fstat64(lp->log_fd, &lp->log_stat) == -1 ||
397 	    (fd = dup(lp->log_fd)) == -1)
398 		return (fmd_log_open_err(lp, errp, errno));
399 
400 	if (ea_fdopen(&lp->log_ea, fd, FMD_CREATOR,
401 	    EO_VALID_HDR | EO_HEAD, O_RDONLY) == -1) {
402 		(void) close(fd);
403 		return (fmd_log_open_err(lp, errp, EFDL_EXACCT));
404 	}
405 
406 	lp->log_abi = abi;
407 	lp->log_flags |= FMD_LF_EAOPEN;
408 	if (getenv("FMD_LOG_DEBUG") != NULL)
409 		lp->log_flags |= FMD_LF_DEBUG;
410 
411 	/*
412 	 * Read the first group of log meta-data: the write-once read-only
413 	 * file header.  We read all records in this group, ignoring all but
414 	 * the VERSION and LABEL, which are required and must be verified.
415 	 */
416 	if ((grp = ea_get_object_tree(&lp->log_ea, 1)) == NULL)
417 		return (fmd_log_open_err(lp, errp, EFDL_EXACCT));
418 
419 	if (grp->eo_catalog != CAT_FMA_GROUP) {
420 		ea_free_object(grp, EUP_ALLOC);
421 		return (fmd_log_open_err(lp, errp, EFDL_EXACCT));
422 	}
423 
424 	for (obj = grp->eo_group.eg_objs; obj != NULL; obj = obj->eo_next) {
425 		switch (obj->eo_catalog) {
426 		case CAT_FMA_VERSION:
427 			lp->log_version = strdup(obj->eo_item.ei_string);
428 			if (lp->log_version == NULL) {
429 				ea_free_object(grp, EUP_ALLOC);
430 				return (fmd_log_open_err(lp, errp, EFDL_NOMEM));
431 			}
432 			break;
433 		case CAT_FMA_LABEL:
434 			lp->log_label = strdup(obj->eo_item.ei_string);
435 			if (lp->log_label == NULL) {
436 				ea_free_object(grp, EUP_ALLOC);
437 				return (fmd_log_open_err(lp, errp, EFDL_NOMEM));
438 			}
439 			break;
440 		case CAT_FMA_OSREL:
441 			lp->log_osrelease = strdup(obj->eo_item.ei_string);
442 			if (lp->log_osrelease == NULL) {
443 				ea_free_object(grp, EUP_ALLOC);
444 				return (fmd_log_open_err(lp, errp, EFDL_NOMEM));
445 			}
446 			break;
447 		case CAT_FMA_OSVER:
448 			lp->log_osversion = strdup(obj->eo_item.ei_string);
449 			if (lp->log_osversion == NULL) {
450 				ea_free_object(grp, EUP_ALLOC);
451 				return (fmd_log_open_err(lp, errp, EFDL_NOMEM));
452 			}
453 			break;
454 		case CAT_FMA_PLAT:
455 			lp->log_platform = strdup(obj->eo_item.ei_string);
456 			if (lp->log_platform == NULL) {
457 				ea_free_object(grp, EUP_ALLOC);
458 				return (fmd_log_open_err(lp, errp, EFDL_NOMEM));
459 			}
460 			break;
461 		case CAT_FMA_UUID:
462 			lp->log_uuid = strdup(obj->eo_item.ei_string);
463 			if (lp->log_uuid == NULL) {
464 				ea_free_object(grp, EUP_ALLOC);
465 				return (fmd_log_open_err(lp, errp, EFDL_NOMEM));
466 			}
467 			break;
468 		}
469 	}
470 
471 	ea_free_object(grp, EUP_ALLOC);
472 
473 	if (lp->log_version == NULL || lp->log_label == NULL)
474 		return (fmd_log_open_err(lp, errp, EFDL_BADHDR));
475 
476 	/*
477 	 * Read the second group of log meta-data: the table of contents.  At
478 	 * present there are no records libfmd_log needs in here, so we just
479 	 * skip over this entire group so that fmd_log_xiter() starts after it.
480 	 */
481 	if ((grp = ea_get_object_tree(&lp->log_ea, 1)) == NULL)
482 		return (fmd_log_open_err(lp, errp, EFDL_EXACCT));
483 
484 	if (grp->eo_catalog != CAT_FMA_GROUP) {
485 		ea_free_object(grp, EUP_ALLOC);
486 		return (fmd_log_open_err(lp, errp, EFDL_EXACCT));
487 	}
488 
489 	ea_free_object(grp, EUP_ALLOC);
490 	lp->log_flags |= FMD_LF_START;
491 
492 	fmd_log_dprintf(lp, "open log %s dev=%lx ino=%llx\n", lp->log_path,
493 	    (ulong_t)lp->log_stat.st_dev, (u_longlong_t)lp->log_stat.st_ino);
494 
495 	return (lp);
496 }
497 
498 void
499 fmd_log_close(fmd_log_t *lp)
500 {
501 	fmd_log_t *xlp, *nlp;
502 
503 	if (lp == NULL)
504 		return; /* permit null lp to simply caller code */
505 
506 	for (xlp = lp->log_xrefs; xlp != NULL; xlp = nlp) {
507 		nlp = xlp->log_xnext;
508 		fmd_log_close(xlp);
509 	}
510 
511 	if (lp->log_flags & FMD_LF_EAOPEN)
512 		(void) ea_close(&lp->log_ea);
513 
514 	if (lp->log_fd >= 0)
515 		(void) close(lp->log_fd);
516 
517 	free(lp->log_path);
518 	free(lp->log_version);
519 	free(lp->log_label);
520 	free(lp->log_osrelease);
521 	free(lp->log_osversion);
522 	free(lp->log_platform);
523 	free(lp->log_uuid);
524 
525 	free(lp);
526 }
527 
528 const char *
529 fmd_log_label(fmd_log_t *lp)
530 {
531 	return (lp->log_label);
532 }
533 
534 void
535 fmd_log_header(fmd_log_t *lp, fmd_log_header_t *hp)
536 {
537 	const char *creator = ea_get_creator(&lp->log_ea);
538 	const char *hostname = ea_get_hostname(&lp->log_ea);
539 
540 	hp->log_creator = creator ? creator : "";
541 	hp->log_hostname = hostname ? hostname : "";
542 	hp->log_label = lp->log_label ? lp->log_label : "";
543 	hp->log_version = lp->log_version ? lp->log_version : "";
544 	hp->log_osrelease = lp->log_osrelease ? lp->log_osrelease : "";
545 	hp->log_osversion = lp->log_osversion ? lp->log_osversion : "";
546 	hp->log_platform = lp->log_platform ? lp->log_platform : "";
547 	if (lp->log_abi > 1)
548 		hp->log_uuid = lp->log_uuid ? lp->log_uuid : "";
549 }
550 
551 /*
552  * Note: this will be verrrry slow for big files.  If this function becomes
553  * important, we'll need to add a function to libexacct to let us rewind.
554  * Currently libexacct has no notion of seeking other than record-at-a-time.
555  */
556 int
557 fmd_log_rewind(fmd_log_t *lp)
558 {
559 	ea_object_t obj, *grp;
560 
561 	if (!(lp->log_flags & FMD_LF_START)) {
562 		while (ea_previous_object(&lp->log_ea, &obj) != EO_ERROR)
563 			continue; /* rewind until beginning of file */
564 
565 		if ((grp = ea_get_object_tree(&lp->log_ea, 1)) == NULL)
566 			return (fmd_log_set_errno(lp, EFDL_EXACCT));
567 		else
568 			ea_free_object(grp, EUP_ALLOC); /* hdr group */
569 
570 		if ((grp = ea_get_object_tree(&lp->log_ea, 1)) == NULL)
571 			return (fmd_log_set_errno(lp, EFDL_EXACCT));
572 		else
573 			ea_free_object(grp, EUP_ALLOC); /* toc group */
574 
575 		lp->log_flags |= FMD_LF_START;
576 	}
577 
578 	return (0);
579 }
580 
581 static int
582 fmd_log_xiter_filter(fmd_log_t *lp, const fmd_log_record_t *rp,
583     uint_t fac, const fmd_log_filtvec_t *fav)
584 {
585 	uint_t i, j;
586 
587 	for (i = 0; i < fac; i++) {
588 		for (j = 0; j < fav[i].filt_argc; j++) {
589 			if (fav[i].filt_argv[j].filt_func(lp, rp,
590 			    fav[i].filt_argv[j].filt_arg) != 0)
591 				break; /* logical OR of this class is true */
592 		}
593 
594 		if (j == fav[i].filt_argc)
595 			return (0); /* logical AND of filter is false */
596 	}
597 
598 	return (1); /* logical AND of filter is true */
599 }
600 
601 static int
602 fmd_log_xiter_filtcmp(const void *lp, const void *rp)
603 {
604 	return ((intptr_t)((fmd_log_filter_t *)lp)->filt_func -
605 	    (intptr_t)((fmd_log_filter_t *)rp)->filt_func);
606 }
607 
608 int
609 fmd_log_filter(fmd_log_t *lp, uint_t fc, fmd_log_filter_t *fv,
610     const fmd_log_record_t *rp)
611 {
612 	fmd_log_filtvec_t *fav = alloca(fc * sizeof (fmd_log_filtvec_t));
613 	uint_t i, fac = 0;
614 
615 	/*
616 	 * If a filter array was provided, create an array of filtvec structs
617 	 * to perform logical AND/OR processing.  See fmd_log_xiter(), below.
618 	 */
619 	bzero(fav, fc * sizeof (fmd_log_filtvec_t));
620 	qsort(fv, fc, sizeof (fmd_log_filter_t), fmd_log_xiter_filtcmp);
621 
622 	for (i = 0; i < fc; i++) {
623 		if (i == 0 || fv[i].filt_func != fv[i - 1].filt_func)
624 			fav[fac++].filt_argv = &fv[i];
625 		fav[fac - 1].filt_argc++;
626 	}
627 
628 	return (fmd_log_xiter_filter(lp, rp, fac, fav));
629 }
630 
631 int
632 fmd_log_xiter(fmd_log_t *lp, uint_t flag, uint_t fc, fmd_log_filter_t *fv,
633     fmd_log_rec_f *rfunc, fmd_log_err_f *efunc, void *private, ulong_t *rcntp)
634 {
635 	fmd_log_record_t rec;
636 	fmd_log_filtvec_t *fav = NULL;
637 	uint_t i, fac = 0;
638 	ulong_t rcnt = 0;
639 	int rv = 0;
640 
641 	if (flag & ~FMD_LOG_XITER_MASK)
642 		return (fmd_log_set_errno(lp, EINVAL));
643 
644 	/*
645 	 * If a filter array was provided, create an array of filtvec structs
646 	 * where each filtvec holds a pointer to an equivalent list of filters,
647 	 * as determined by their filt_func.  We sort the input array by func,
648 	 * and then fill in the filtvec struct array.  We can then compute the
649 	 * logical OR of equivalent filters by iterating over filt_argv, and
650 	 * we can compute the logical AND of 'fv' by iterating over filt_argc.
651 	 */
652 	if (fc != 0) {
653 		if ((fav = calloc(fc, sizeof (fmd_log_filtvec_t))) == NULL)
654 			return (fmd_log_set_errno(lp, EFDL_NOMEM));
655 
656 		qsort(fv, fc, sizeof (fmd_log_filter_t), fmd_log_xiter_filtcmp);
657 
658 		for (i = 0; i < fc; i++) {
659 			if (i == 0 || fv[i].filt_func != fv[i - 1].filt_func)
660 				fav[fac++].filt_argv = &fv[i];
661 			fav[fac - 1].filt_argc++;
662 		}
663 	}
664 
665 	lp->log_flags &= ~FMD_LF_START;
666 	ea_clear(&lp->log_ea);
667 
668 	do {
669 		if (fmd_log_load_record(lp, flag, &rec) != 0) {
670 			if (lp->log_errno == EFDL_EXACCT + EXR_EOF)
671 				break; /* end-of-file reached */
672 			rv = efunc ? efunc(lp, private) : -1;
673 			rcnt++;
674 		} else {
675 			if (fc == 0 || fmd_log_xiter_filter(lp, &rec, fac, fav))
676 				rv = rfunc(lp, &rec, private);
677 
678 			fmd_log_free_record(&rec);
679 			rcnt++;
680 		}
681 	} while (rv == 0);
682 
683 	if (fac != 0)
684 		free(fav);
685 
686 	if (rcntp != NULL)
687 		*rcntp = rcnt;
688 
689 	return (rv);
690 }
691 
692 int
693 fmd_log_iter(fmd_log_t *lp, fmd_log_rec_f *rfunc, void *private)
694 {
695 	return (fmd_log_xiter(lp, 0, 0, NULL, rfunc, NULL, private, NULL));
696 }
697 
698 int
699 fmd_log_seek(fmd_log_t *lp, off64_t off)
700 {
701 	lp->log_flags &= ~FMD_LF_START;
702 	ea_clear(&lp->log_ea);
703 
704 	if (lseek64(lp->log_fd, off, SEEK_SET) != off)
705 		return (fmd_log_set_errno(lp, errno));
706 
707 	return (0);
708 }
709 
710 static const char *const _fmd_errs[] = {
711 	"client requires newer version of libfmd_log",	/* EFDL_VERSION */
712 	"required memory allocation failed",		/* EFDL_NOMEM */
713 	"log header did not contain required field",	/* EFDL_BADHDR */
714 	"log record did not contain protocol class",	/* EFDL_NOCLASS */
715 	"log record has invalid catalog tag",		/* EFDL_BADTAG */
716 	"log record has invalid cross-reference group",	/* EFDL_BADREF */
717 	"log record has invalid cross-reference dev_t",	/* EFDL_BADDEV */
718 	"log record was not of expected type",		/* EFDL_EXACCT + OK */
719 	"log access system call failed",		/* EXR_SYSCALL_FAIL */
720 	"log file corruption detected",			/* EXR_CORRUPT_FILE */
721 	"end-of-file reached",				/* EXR_EOF */
722 	"log file does not have appropriate creator",	/* EXR_NO_CREATOR */
723 	"invalid unpack buffer specified",		/* EXR_INVALID_BUF */
724 	"invalid exacct operation for log file",	/* EXR_NOTSUPP */
725 	"log file requires newer version of libexacct",	/* EXR_UNKN_VERSION */
726 	"invalid object buffer specified",		/* EXR_INVALID_OBJ */
727 };
728 
729 static const int _fmd_nerr = sizeof (_fmd_errs) / sizeof (_fmd_errs[0]);
730 
731 /*ARGSUSED*/
732 const char *
733 fmd_log_errmsg(fmd_log_t *lp, int err)
734 {
735 	const char *msg;
736 
737 	if (err >= EFDL_BASE && err - EFDL_BASE < _fmd_nerr)
738 		msg = _fmd_errs[err - EFDL_BASE];
739 	else
740 		msg = strerror(err);
741 
742 	return (msg ? msg : "unknown error");
743 }
744 
745 int
746 fmd_log_errno(fmd_log_t *lp)
747 {
748 	return (lp->log_errno);
749 }
750