log.c revision 1.1 1 /* $NetBSD: log.c,v 1.1 2024/02/18 20:57:49 christos Exp $ */
2
3 /*
4 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5 *
6 * SPDX-License-Identifier: MPL-2.0
7 *
8 * This Source Code Form is subject to the terms of the Mozilla Public
9 * License, v. 2.0. If a copy of the MPL was not distributed with this
10 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
11 *
12 * See the COPYRIGHT file distributed with this work for additional
13 * information regarding copyright ownership.
14 */
15
16 /*! \file */
17
18 #include <errno.h>
19 #include <inttypes.h>
20 #include <limits.h>
21 #include <stdbool.h>
22 #include <stdlib.h>
23 #include <sys/types.h> /* dev_t FreeBSD 2.1 */
24 #include <time.h>
25
26 #include <isc/atomic.h>
27 #include <isc/dir.h>
28 #include <isc/file.h>
29 #include <isc/log.h>
30 #include <isc/magic.h>
31 #include <isc/mem.h>
32 #include <isc/platform.h>
33 #include <isc/print.h>
34 #include <isc/rwlock.h>
35 #include <isc/stat.h>
36 #include <isc/stdio.h>
37 #include <isc/string.h>
38 #include <isc/time.h>
39 #include <isc/util.h>
40
41 #define LCTX_MAGIC ISC_MAGIC('L', 'c', 't', 'x')
42 #define VALID_CONTEXT(lctx) ISC_MAGIC_VALID(lctx, LCTX_MAGIC)
43
44 #define LCFG_MAGIC ISC_MAGIC('L', 'c', 'f', 'g')
45 #define VALID_CONFIG(lcfg) ISC_MAGIC_VALID(lcfg, LCFG_MAGIC)
46
47 #define RDLOCK(lp) RWLOCK(lp, isc_rwlocktype_read);
48 #define WRLOCK(lp) RWLOCK(lp, isc_rwlocktype_write);
49 #define RDUNLOCK(lp) RWUNLOCK(lp, isc_rwlocktype_read);
50 #define WRUNLOCK(lp) RWUNLOCK(lp, isc_rwlocktype_write);
51
52 /*
53 * XXXDCL make dynamic?
54 */
55 #define LOG_BUFFER_SIZE (8 * 1024)
56
57 /*!
58 * This is the structure that holds each named channel. A simple linked
59 * list chains all of the channels together, so an individual channel is
60 * found by doing strcmp()s with the names down the list. Their should
61 * be no performance penalty from this as it is expected that the number
62 * of named channels will be no more than a dozen or so, and name lookups
63 * from the head of the list are only done when isc_log_usechannel() is
64 * called, which should also be very infrequent.
65 */
66 typedef struct isc_logchannel isc_logchannel_t;
67
68 struct isc_logchannel {
69 char *name;
70 unsigned int type;
71 int level;
72 unsigned int flags;
73 isc_logdestination_t destination;
74 ISC_LINK(isc_logchannel_t) link;
75 };
76
77 /*!
78 * The logchannellist structure associates categories and modules with
79 * channels. First the appropriate channellist is found based on the
80 * category, and then each structure in the linked list is checked for
81 * a matching module. It is expected that the number of channels
82 * associated with any given category will be very short, no more than
83 * three or four in the more unusual cases.
84 */
85 typedef struct isc_logchannellist isc_logchannellist_t;
86
87 struct isc_logchannellist {
88 const isc_logmodule_t *module;
89 isc_logchannel_t *channel;
90 ISC_LINK(isc_logchannellist_t) link;
91 };
92
93 /*!
94 * This structure is used to remember messages for pruning via
95 * isc_log_[v]write1().
96 */
97 typedef struct isc_logmessage isc_logmessage_t;
98
99 struct isc_logmessage {
100 char *text;
101 isc_time_t time;
102 ISC_LINK(isc_logmessage_t) link;
103 };
104
105 /*!
106 * The isc_logconfig structure is used to store the configurable information
107 * about where messages are actually supposed to be sent -- the information
108 * that could changed based on some configuration file, as opposed to the
109 * the category/module specification of isc_log_[v]write[1] that is compiled
110 * into a program, or the debug_level which is dynamic state information.
111 */
112 struct isc_logconfig {
113 unsigned int magic;
114 isc_log_t *lctx;
115 ISC_LIST(isc_logchannel_t) channels;
116 ISC_LIST(isc_logchannellist_t) * channellists;
117 unsigned int channellist_count;
118 unsigned int duplicate_interval;
119 int_fast32_t highest_level;
120 char *tag;
121 bool dynamic;
122 };
123
124 /*!
125 * This isc_log structure provides the context for the isc_log functions.
126 * The log context locks itself in isc_log_doit, the internal backend to
127 * isc_log_write. The locking is necessary both to provide exclusive access
128 * to the buffer into which the message is formatted and to guard against
129 * competing threads trying to write to the same syslog resource. (On
130 * some systems, such as BSD/OS, stdio is thread safe but syslog is not.)
131 * Unfortunately, the lock cannot guard against a _different_ logging
132 * context in the same program competing for syslog's attention. Thus
133 * There Can Be Only One, but this is not enforced.
134 * XXXDCL enforce it?
135 *
136 * Note that the category and module information is not locked.
137 * This is because in the usual case, only one isc_log_t is ever created
138 * in a program, and the category/module registration happens only once.
139 * XXXDCL it might be wise to add more locking overall.
140 */
141 struct isc_log {
142 /* Not locked. */
143 unsigned int magic;
144 isc_mem_t *mctx;
145 isc_logcategory_t *categories;
146 unsigned int category_count;
147 isc_logmodule_t *modules;
148 unsigned int module_count;
149 atomic_int_fast32_t debug_level;
150 isc_rwlock_t lcfg_rwl;
151 /* Locked by isc_log lcfg_rwl */
152 isc_logconfig_t *logconfig;
153 isc_mutex_t lock;
154 /* Locked by isc_log lock. */
155 char buffer[LOG_BUFFER_SIZE];
156 ISC_LIST(isc_logmessage_t) messages;
157 atomic_bool dynamic;
158 atomic_int_fast32_t highest_level;
159 };
160
161 /*!
162 * Used when ISC_LOG_PRINTLEVEL is enabled for a channel.
163 */
164 static const char *log_level_strings[] = { "debug", "info", "notice",
165 "warning", "error", "critical" };
166
167 /*!
168 * Used to convert ISC_LOG_* priorities into syslog priorities.
169 * XXXDCL This will need modification for NT.
170 */
171 static const int syslog_map[] = { LOG_DEBUG, LOG_INFO, LOG_NOTICE,
172 LOG_WARNING, LOG_ERR, LOG_CRIT };
173
174 /*!
175 * When adding new categories, a corresponding ISC_LOGCATEGORY_foo
176 * definition needs to be added to <isc/log.h>.
177 *
178 * The default category is provided so that the internal default can
179 * be overridden. Since the default is always looked up as the first
180 * channellist in the log context, it must come first in isc_categories[].
181 */
182 LIBISC_EXTERNAL_DATA isc_logcategory_t isc_categories[] = { { "default",
183 0 }, /* "default
184 must come
185 first. */
186 { "general", 0 },
187 { NULL, 0 } };
188
189 /*!
190 * See above comment for categories on LIBISC_EXTERNAL_DATA, and apply it to
191 * modules.
192 */
193 LIBISC_EXTERNAL_DATA isc_logmodule_t isc_modules[] = {
194 { "socket", 0 }, { "time", 0 }, { "interface", 0 }, { "timer", 0 },
195 { "file", 0 }, { "netmgr", 0 }, { "other", 0 }, { NULL, 0 }
196 };
197
198 /*!
199 * This essentially constant structure must be filled in at run time,
200 * because its channel member is pointed to a channel that is created
201 * dynamically with isc_log_createchannel.
202 */
203 static isc_logchannellist_t default_channel;
204
205 /*!
206 * libisc logs to this context.
207 */
208 LIBISC_EXTERNAL_DATA isc_log_t *isc_lctx = NULL;
209
210 /*!
211 * Forward declarations.
212 */
213 static void
214 assignchannel(isc_logconfig_t *lcfg, unsigned int category_id,
215 const isc_logmodule_t *module, isc_logchannel_t *channel);
216
217 static void
218 sync_channellist(isc_logconfig_t *lcfg);
219
220 static void
221 sync_highest_level(isc_log_t *lctx, isc_logconfig_t *lcfg);
222
223 static isc_result_t
224 greatest_version(isc_logfile_t *file, int versions, int *greatest);
225
226 static void
227 isc_log_doit(isc_log_t *lctx, isc_logcategory_t *category,
228 isc_logmodule_t *module, int level, bool write_once,
229 const char *format, va_list args) ISC_FORMAT_PRINTF(6, 0);
230
231 /*@{*/
232 /*!
233 * Convenience macros.
234 */
235
236 #define FACILITY(channel) (channel->destination.facility)
237 #define FILE_NAME(channel) (channel->destination.file.name)
238 #define FILE_STREAM(channel) (channel->destination.file.stream)
239 #define FILE_VERSIONS(channel) (channel->destination.file.versions)
240 #define FILE_SUFFIX(channel) (channel->destination.file.suffix)
241 #define FILE_MAXSIZE(channel) (channel->destination.file.maximum_size)
242 #define FILE_MAXREACHED(channel) (channel->destination.file.maximum_reached)
243
244 /*@}*/
245 /****
246 **** Public interfaces.
247 ****/
248
249 /*
250 * Establish a new logging context, with default channels.
251 */
252 void
253 isc_log_create(isc_mem_t *mctx, isc_log_t **lctxp, isc_logconfig_t **lcfgp) {
254 isc_log_t *lctx;
255 isc_logconfig_t *lcfg = NULL;
256
257 REQUIRE(mctx != NULL);
258 REQUIRE(lctxp != NULL && *lctxp == NULL);
259 REQUIRE(lcfgp == NULL || *lcfgp == NULL);
260
261 lctx = isc_mem_get(mctx, sizeof(*lctx));
262 lctx->mctx = NULL;
263 isc_mem_attach(mctx, &lctx->mctx);
264 lctx->categories = NULL;
265 lctx->category_count = 0;
266 lctx->modules = NULL;
267 lctx->module_count = 0;
268 atomic_init(&lctx->debug_level, 0);
269
270 ISC_LIST_INIT(lctx->messages);
271
272 isc_mutex_init(&lctx->lock);
273 isc_rwlock_init(&lctx->lcfg_rwl, 0, 0);
274
275 /*
276 * Normally setting the magic number is the last step done
277 * in a creation function, but a valid log context is needed
278 * by isc_log_registercategories and isc_logconfig_create.
279 * If either fails, the lctx is destroyed and not returned
280 * to the caller.
281 */
282 lctx->magic = LCTX_MAGIC;
283
284 isc_log_registercategories(lctx, isc_categories);
285 isc_log_registermodules(lctx, isc_modules);
286 isc_logconfig_create(lctx, &lcfg);
287
288 sync_channellist(lcfg);
289
290 lctx->logconfig = lcfg;
291
292 atomic_init(&lctx->highest_level, lcfg->highest_level);
293 atomic_init(&lctx->dynamic, lcfg->dynamic);
294
295 *lctxp = lctx;
296 if (lcfgp != NULL) {
297 *lcfgp = lcfg;
298 }
299 }
300
301 void
302 isc_logconfig_create(isc_log_t *lctx, isc_logconfig_t **lcfgp) {
303 isc_logconfig_t *lcfg;
304 isc_logdestination_t destination;
305 int level = ISC_LOG_INFO;
306
307 REQUIRE(lcfgp != NULL && *lcfgp == NULL);
308 REQUIRE(VALID_CONTEXT(lctx));
309
310 lcfg = isc_mem_get(lctx->mctx, sizeof(*lcfg));
311
312 lcfg->lctx = lctx;
313 lcfg->channellists = NULL;
314 lcfg->channellist_count = 0;
315 lcfg->duplicate_interval = 0;
316 lcfg->highest_level = level;
317 lcfg->tag = NULL;
318 lcfg->dynamic = false;
319 ISC_LIST_INIT(lcfg->channels);
320 lcfg->magic = LCFG_MAGIC;
321
322 /*
323 * Create the default channels:
324 * default_syslog, default_stderr, default_debug and null.
325 */
326 destination.facility = LOG_DAEMON;
327 isc_log_createchannel(lcfg, "default_syslog", ISC_LOG_TOSYSLOG, level,
328 &destination, 0);
329
330 destination.file.stream = stderr;
331 destination.file.name = NULL;
332 destination.file.versions = ISC_LOG_ROLLNEVER;
333 destination.file.suffix = isc_log_rollsuffix_increment;
334 destination.file.maximum_size = 0;
335 isc_log_createchannel(lcfg, "default_stderr", ISC_LOG_TOFILEDESC, level,
336 &destination, ISC_LOG_PRINTTIME);
337
338 /*
339 * Set the default category's channel to default_stderr,
340 * which is at the head of the channels list because it was
341 * just created.
342 */
343 default_channel.channel = ISC_LIST_HEAD(lcfg->channels);
344
345 destination.file.stream = stderr;
346 destination.file.name = NULL;
347 destination.file.versions = ISC_LOG_ROLLNEVER;
348 destination.file.suffix = isc_log_rollsuffix_increment;
349 destination.file.maximum_size = 0;
350 isc_log_createchannel(lcfg, "default_debug", ISC_LOG_TOFILEDESC,
351 ISC_LOG_DYNAMIC, &destination, ISC_LOG_PRINTTIME);
352
353 isc_log_createchannel(lcfg, "null", ISC_LOG_TONULL, ISC_LOG_DYNAMIC,
354 NULL, 0);
355
356 *lcfgp = lcfg;
357 }
358
359 void
360 isc_logconfig_use(isc_log_t *lctx, isc_logconfig_t *lcfg) {
361 isc_logconfig_t *old_cfg;
362
363 REQUIRE(VALID_CONTEXT(lctx));
364 REQUIRE(VALID_CONFIG(lcfg));
365 REQUIRE(lcfg->lctx == lctx);
366
367 /*
368 * Ensure that lcfg->channellist_count == lctx->category_count.
369 * They won't be equal if isc_log_usechannel has not been called
370 * since any call to isc_log_registercategories.
371 */
372 sync_channellist(lcfg);
373
374 WRLOCK(&lctx->lcfg_rwl);
375 old_cfg = lctx->logconfig;
376 lctx->logconfig = lcfg;
377 sync_highest_level(lctx, lcfg);
378 WRUNLOCK(&lctx->lcfg_rwl);
379
380 isc_logconfig_destroy(&old_cfg);
381 }
382
383 void
384 isc_log_destroy(isc_log_t **lctxp) {
385 isc_log_t *lctx;
386 isc_logconfig_t *lcfg;
387 isc_mem_t *mctx;
388 isc_logmessage_t *message;
389
390 REQUIRE(lctxp != NULL && VALID_CONTEXT(*lctxp));
391
392 lctx = *lctxp;
393 *lctxp = NULL;
394 mctx = lctx->mctx;
395
396 /* Stop the logging as a first thing */
397 atomic_store_release(&lctx->debug_level, 0);
398 atomic_store_release(&lctx->highest_level, 0);
399 atomic_store_release(&lctx->dynamic, false);
400
401 WRLOCK(&lctx->lcfg_rwl);
402 lcfg = lctx->logconfig;
403 lctx->logconfig = NULL;
404 WRUNLOCK(&lctx->lcfg_rwl);
405
406 if (lcfg != NULL) {
407 isc_logconfig_destroy(&lcfg);
408 }
409
410 isc_rwlock_destroy(&lctx->lcfg_rwl);
411 isc_mutex_destroy(&lctx->lock);
412
413 while ((message = ISC_LIST_HEAD(lctx->messages)) != NULL) {
414 ISC_LIST_UNLINK(lctx->messages, message, link);
415
416 isc_mem_put(mctx, message,
417 sizeof(*message) + strlen(message->text) + 1);
418 }
419
420 lctx->buffer[0] = '\0';
421 lctx->categories = NULL;
422 lctx->category_count = 0;
423 lctx->modules = NULL;
424 lctx->module_count = 0;
425 lctx->mctx = NULL;
426 lctx->magic = 0;
427
428 isc_mem_putanddetach(&mctx, lctx, sizeof(*lctx));
429 }
430
431 void
432 isc_logconfig_destroy(isc_logconfig_t **lcfgp) {
433 isc_logconfig_t *lcfg;
434 isc_mem_t *mctx;
435 isc_logchannel_t *channel;
436 char *filename;
437 unsigned int i;
438
439 REQUIRE(lcfgp != NULL && VALID_CONFIG(*lcfgp));
440
441 lcfg = *lcfgp;
442 *lcfgp = NULL;
443
444 /*
445 * This function cannot be called with a logconfig that is in
446 * use by a log context.
447 */
448 REQUIRE(lcfg->lctx != NULL);
449
450 RDLOCK(&lcfg->lctx->lcfg_rwl);
451 REQUIRE(lcfg->lctx->logconfig != lcfg);
452 RDUNLOCK(&lcfg->lctx->lcfg_rwl);
453
454 mctx = lcfg->lctx->mctx;
455
456 while ((channel = ISC_LIST_HEAD(lcfg->channels)) != NULL) {
457 ISC_LIST_UNLINK(lcfg->channels, channel, link);
458
459 if (channel->type == ISC_LOG_TOFILE) {
460 /*
461 * The filename for the channel may have ultimately
462 * started its life in user-land as a const string,
463 * but in isc_log_createchannel it gets copied
464 * into writable memory and is not longer truly const.
465 */
466 DE_CONST(FILE_NAME(channel), filename);
467 isc_mem_free(mctx, filename);
468
469 if (FILE_STREAM(channel) != NULL) {
470 (void)fclose(FILE_STREAM(channel));
471 }
472 }
473
474 isc_mem_free(mctx, channel->name);
475 isc_mem_put(mctx, channel, sizeof(*channel));
476 }
477
478 for (i = 0; i < lcfg->channellist_count; i++) {
479 isc_logchannellist_t *item;
480 while ((item = ISC_LIST_HEAD(lcfg->channellists[i])) != NULL) {
481 ISC_LIST_UNLINK(lcfg->channellists[i], item, link);
482 isc_mem_put(mctx, item, sizeof(*item));
483 }
484 }
485
486 if (lcfg->channellist_count > 0) {
487 isc_mem_put(mctx, lcfg->channellists,
488 lcfg->channellist_count *
489 sizeof(ISC_LIST(isc_logchannellist_t)));
490 }
491
492 lcfg->dynamic = false;
493 if (lcfg->tag != NULL) {
494 isc_mem_free(lcfg->lctx->mctx, lcfg->tag);
495 }
496 lcfg->tag = NULL;
497 lcfg->highest_level = 0;
498 lcfg->duplicate_interval = 0;
499 lcfg->magic = 0;
500
501 isc_mem_put(mctx, lcfg, sizeof(*lcfg));
502 }
503
504 void
505 isc_log_registercategories(isc_log_t *lctx, isc_logcategory_t categories[]) {
506 isc_logcategory_t *catp;
507
508 REQUIRE(VALID_CONTEXT(lctx));
509 REQUIRE(categories != NULL && categories[0].name != NULL);
510
511 /*
512 * XXXDCL This somewhat sleazy situation of using the last pointer
513 * in one category array to point to the next array exists because
514 * this registration function returns void and I didn't want to have
515 * change everything that used it by making it return an isc_result_t.
516 * It would need to do that if it had to allocate memory to store
517 * pointers to each array passed in.
518 */
519 if (lctx->categories == NULL) {
520 lctx->categories = categories;
521 } else {
522 /*
523 * Adjust the last (NULL) pointer of the already registered
524 * categories to point to the incoming array.
525 */
526 for (catp = lctx->categories; catp->name != NULL;) {
527 if (catp->id == UINT_MAX) {
528 /*
529 * The name pointer points to the next array.
530 * Ick.
531 */
532 DE_CONST(catp->name, catp);
533 } else {
534 catp++;
535 }
536 }
537
538 catp->name = (void *)categories;
539 catp->id = UINT_MAX;
540 }
541
542 /*
543 * Update the id number of the category with its new global id.
544 */
545 for (catp = categories; catp->name != NULL; catp++) {
546 catp->id = lctx->category_count++;
547 }
548 }
549
550 isc_logcategory_t *
551 isc_log_categorybyname(isc_log_t *lctx, const char *name) {
552 isc_logcategory_t *catp;
553
554 REQUIRE(VALID_CONTEXT(lctx));
555 REQUIRE(name != NULL);
556
557 for (catp = lctx->categories; catp->name != NULL;) {
558 if (catp->id == UINT_MAX) {
559 /*
560 * catp is neither modified nor returned to the
561 * caller, so removing its const qualifier is ok.
562 */
563 DE_CONST(catp->name, catp);
564 } else {
565 if (strcmp(catp->name, name) == 0) {
566 return (catp);
567 }
568 catp++;
569 }
570 }
571
572 return (NULL);
573 }
574
575 void
576 isc_log_registermodules(isc_log_t *lctx, isc_logmodule_t modules[]) {
577 isc_logmodule_t *modp;
578
579 REQUIRE(VALID_CONTEXT(lctx));
580 REQUIRE(modules != NULL && modules[0].name != NULL);
581
582 /*
583 * XXXDCL This somewhat sleazy situation of using the last pointer
584 * in one category array to point to the next array exists because
585 * this registration function returns void and I didn't want to have
586 * change everything that used it by making it return an isc_result_t.
587 * It would need to do that if it had to allocate memory to store
588 * pointers to each array passed in.
589 */
590 if (lctx->modules == NULL) {
591 lctx->modules = modules;
592 } else {
593 /*
594 * Adjust the last (NULL) pointer of the already registered
595 * modules to point to the incoming array.
596 */
597 for (modp = lctx->modules; modp->name != NULL;) {
598 if (modp->id == UINT_MAX) {
599 /*
600 * The name pointer points to the next array.
601 * Ick.
602 */
603 DE_CONST(modp->name, modp);
604 } else {
605 modp++;
606 }
607 }
608
609 modp->name = (void *)modules;
610 modp->id = UINT_MAX;
611 }
612
613 /*
614 * Update the id number of the module with its new global id.
615 */
616 for (modp = modules; modp->name != NULL; modp++) {
617 modp->id = lctx->module_count++;
618 }
619 }
620
621 isc_logmodule_t *
622 isc_log_modulebyname(isc_log_t *lctx, const char *name) {
623 isc_logmodule_t *modp;
624
625 REQUIRE(VALID_CONTEXT(lctx));
626 REQUIRE(name != NULL);
627
628 for (modp = lctx->modules; modp->name != NULL;) {
629 if (modp->id == UINT_MAX) {
630 /*
631 * modp is neither modified nor returned to the
632 * caller, so removing its const qualifier is ok.
633 */
634 DE_CONST(modp->name, modp);
635 } else {
636 if (strcmp(modp->name, name) == 0) {
637 return (modp);
638 }
639 modp++;
640 }
641 }
642
643 return (NULL);
644 }
645
646 void
647 isc_log_createchannel(isc_logconfig_t *lcfg, const char *name,
648 unsigned int type, int level,
649 const isc_logdestination_t *destination,
650 unsigned int flags) {
651 isc_logchannel_t *channel;
652 isc_mem_t *mctx;
653 unsigned int permitted = ISC_LOG_PRINTALL | ISC_LOG_DEBUGONLY |
654 ISC_LOG_BUFFERED | ISC_LOG_ISO8601 |
655 ISC_LOG_UTC;
656
657 REQUIRE(VALID_CONFIG(lcfg));
658 REQUIRE(name != NULL);
659 REQUIRE(type == ISC_LOG_TOSYSLOG || type == ISC_LOG_TOFILE ||
660 type == ISC_LOG_TOFILEDESC || type == ISC_LOG_TONULL);
661 REQUIRE(destination != NULL || type == ISC_LOG_TONULL);
662 REQUIRE(level >= ISC_LOG_CRITICAL);
663 REQUIRE((flags & ~permitted) == 0);
664
665 /* XXXDCL find duplicate names? */
666
667 mctx = lcfg->lctx->mctx;
668
669 channel = isc_mem_get(mctx, sizeof(*channel));
670
671 channel->name = isc_mem_strdup(mctx, name);
672
673 channel->type = type;
674 channel->level = level;
675 channel->flags = flags;
676 ISC_LINK_INIT(channel, link);
677
678 switch (type) {
679 case ISC_LOG_TOSYSLOG:
680 FACILITY(channel) = destination->facility;
681 break;
682
683 case ISC_LOG_TOFILE:
684 /*
685 * The file name is copied because greatest_version wants
686 * to scribble on it, so it needs to be definitely in
687 * writable memory.
688 */
689 FILE_NAME(channel) = isc_mem_strdup(mctx,
690 destination->file.name);
691 FILE_STREAM(channel) = NULL;
692 FILE_VERSIONS(channel) = destination->file.versions;
693 FILE_SUFFIX(channel) = destination->file.suffix;
694 FILE_MAXSIZE(channel) = destination->file.maximum_size;
695 FILE_MAXREACHED(channel) = false;
696 break;
697
698 case ISC_LOG_TOFILEDESC:
699 FILE_NAME(channel) = NULL;
700 FILE_STREAM(channel) = destination->file.stream;
701 FILE_MAXSIZE(channel) = 0;
702 FILE_VERSIONS(channel) = ISC_LOG_ROLLNEVER;
703 FILE_SUFFIX(channel) = isc_log_rollsuffix_increment;
704 break;
705
706 case ISC_LOG_TONULL:
707 /* Nothing. */
708 break;
709
710 default:
711 UNREACHABLE();
712 }
713
714 ISC_LIST_PREPEND(lcfg->channels, channel, link);
715
716 /*
717 * If default_stderr was redefined, make the default category
718 * point to the new default_stderr.
719 */
720 if (strcmp(name, "default_stderr") == 0) {
721 default_channel.channel = channel;
722 }
723 }
724
725 isc_result_t
726 isc_log_usechannel(isc_logconfig_t *lcfg, const char *name,
727 const isc_logcategory_t *category,
728 const isc_logmodule_t *module) {
729 isc_log_t *lctx;
730 isc_logchannel_t *channel;
731
732 REQUIRE(VALID_CONFIG(lcfg));
733 REQUIRE(name != NULL);
734
735 lctx = lcfg->lctx;
736
737 REQUIRE(category == NULL || category->id < lctx->category_count);
738 REQUIRE(module == NULL || module->id < lctx->module_count);
739
740 for (channel = ISC_LIST_HEAD(lcfg->channels); channel != NULL;
741 channel = ISC_LIST_NEXT(channel, link))
742 {
743 if (strcmp(name, channel->name) == 0) {
744 break;
745 }
746 }
747
748 if (channel == NULL) {
749 return (ISC_R_NOTFOUND);
750 }
751
752 if (category != NULL) {
753 assignchannel(lcfg, category->id, module, channel);
754 } else {
755 /*
756 * Assign to all categories. Note that this includes
757 * the default channel.
758 */
759 for (size_t i = 0; i < lctx->category_count; i++) {
760 assignchannel(lcfg, i, module, channel);
761 }
762 }
763
764 /*
765 * Update the highest logging level, if the current lcfg is in use.
766 */
767 if (lcfg->lctx->logconfig == lcfg) {
768 sync_highest_level(lctx, lcfg);
769 }
770
771 return (ISC_R_SUCCESS);
772 }
773
774 void
775 isc_log_write(isc_log_t *lctx, isc_logcategory_t *category,
776 isc_logmodule_t *module, int level, const char *format, ...) {
777 va_list args;
778
779 /*
780 * Contract checking is done in isc_log_doit().
781 */
782
783 va_start(args, format);
784 isc_log_doit(lctx, category, module, level, false, format, args);
785 va_end(args);
786 }
787
788 void
789 isc_log_vwrite(isc_log_t *lctx, isc_logcategory_t *category,
790 isc_logmodule_t *module, int level, const char *format,
791 va_list args) {
792 /*
793 * Contract checking is done in isc_log_doit().
794 */
795 isc_log_doit(lctx, category, module, level, false, format, args);
796 }
797
798 void
799 isc_log_write1(isc_log_t *lctx, isc_logcategory_t *category,
800 isc_logmodule_t *module, int level, const char *format, ...) {
801 va_list args;
802
803 /*
804 * Contract checking is done in isc_log_doit().
805 */
806
807 va_start(args, format);
808 isc_log_doit(lctx, category, module, level, true, format, args);
809 va_end(args);
810 }
811
812 void
813 isc_log_vwrite1(isc_log_t *lctx, isc_logcategory_t *category,
814 isc_logmodule_t *module, int level, const char *format,
815 va_list args) {
816 /*
817 * Contract checking is done in isc_log_doit().
818 */
819 isc_log_doit(lctx, category, module, level, true, format, args);
820 }
821
822 void
823 isc_log_setcontext(isc_log_t *lctx) {
824 isc_lctx = lctx;
825 }
826
827 void
828 isc_log_setdebuglevel(isc_log_t *lctx, unsigned int level) {
829 REQUIRE(VALID_CONTEXT(lctx));
830
831 atomic_store_release(&lctx->debug_level, level);
832 /*
833 * Close ISC_LOG_DEBUGONLY channels if level is zero.
834 */
835 if (level == 0) {
836 RDLOCK(&lctx->lcfg_rwl);
837 isc_logconfig_t *lcfg = lctx->logconfig;
838 if (lcfg != NULL) {
839 LOCK(&lctx->lock);
840 for (isc_logchannel_t *channel =
841 ISC_LIST_HEAD(lcfg->channels);
842 channel != NULL;
843 channel = ISC_LIST_NEXT(channel, link))
844 {
845 if (channel->type == ISC_LOG_TOFILE &&
846 (channel->flags & ISC_LOG_DEBUGONLY) != 0 &&
847 FILE_STREAM(channel) != NULL)
848 {
849 (void)fclose(FILE_STREAM(channel));
850 FILE_STREAM(channel) = NULL;
851 }
852 }
853 UNLOCK(&lctx->lock);
854 }
855 RDUNLOCK(&lctx->lcfg_rwl);
856 }
857 }
858
859 unsigned int
860 isc_log_getdebuglevel(isc_log_t *lctx) {
861 REQUIRE(VALID_CONTEXT(lctx));
862
863 return (atomic_load_acquire(&lctx->debug_level));
864 }
865
866 void
867 isc_log_setduplicateinterval(isc_logconfig_t *lcfg, unsigned int interval) {
868 REQUIRE(VALID_CONFIG(lcfg));
869
870 lcfg->duplicate_interval = interval;
871 }
872
873 unsigned int
874 isc_log_getduplicateinterval(isc_logconfig_t *lcfg) {
875 REQUIRE(VALID_CONTEXT(lcfg));
876
877 return (lcfg->duplicate_interval);
878 }
879
880 void
881 isc_log_settag(isc_logconfig_t *lcfg, const char *tag) {
882 REQUIRE(VALID_CONFIG(lcfg));
883
884 if (tag != NULL && *tag != '\0') {
885 if (lcfg->tag != NULL) {
886 isc_mem_free(lcfg->lctx->mctx, lcfg->tag);
887 }
888 lcfg->tag = isc_mem_strdup(lcfg->lctx->mctx, tag);
889 } else {
890 if (lcfg->tag != NULL) {
891 isc_mem_free(lcfg->lctx->mctx, lcfg->tag);
892 }
893 lcfg->tag = NULL;
894 }
895 }
896
897 char *
898 isc_log_gettag(isc_logconfig_t *lcfg) {
899 REQUIRE(VALID_CONFIG(lcfg));
900
901 return (lcfg->tag);
902 }
903
904 /* XXXDCL NT -- This interface will assuredly be changing. */
905 void
906 isc_log_opensyslog(const char *tag, int options, int facility) {
907 (void)openlog(tag, options, facility);
908 }
909
910 void
911 isc_log_closefilelogs(isc_log_t *lctx) {
912 REQUIRE(VALID_CONTEXT(lctx));
913
914 RDLOCK(&lctx->lcfg_rwl);
915 isc_logconfig_t *lcfg = lctx->logconfig;
916 if (lcfg != NULL) {
917 LOCK(&lctx->lock);
918 for (isc_logchannel_t *channel = ISC_LIST_HEAD(lcfg->channels);
919 channel != NULL; channel = ISC_LIST_NEXT(channel, link))
920 {
921 if (channel->type == ISC_LOG_TOFILE &&
922 FILE_STREAM(channel) != NULL)
923 {
924 (void)fclose(FILE_STREAM(channel));
925 FILE_STREAM(channel) = NULL;
926 }
927 }
928 UNLOCK(&lctx->lock);
929 }
930 RDUNLOCK(&lctx->lcfg_rwl);
931 }
932
933 /****
934 **** Internal functions
935 ****/
936
937 static void
938 assignchannel(isc_logconfig_t *lcfg, unsigned int category_id,
939 const isc_logmodule_t *module, isc_logchannel_t *channel) {
940 isc_logchannellist_t *new_item;
941 isc_log_t *lctx;
942
943 REQUIRE(VALID_CONFIG(lcfg));
944
945 lctx = lcfg->lctx;
946
947 REQUIRE(category_id < lctx->category_count);
948 REQUIRE(module == NULL || module->id < lctx->module_count);
949 REQUIRE(channel != NULL);
950
951 /*
952 * Ensure lcfg->channellist_count == lctx->category_count.
953 */
954 sync_channellist(lcfg);
955
956 new_item = isc_mem_get(lctx->mctx, sizeof(*new_item));
957
958 new_item->channel = channel;
959 new_item->module = module;
960 ISC_LIST_INITANDPREPEND(lcfg->channellists[category_id], new_item,
961 link);
962
963 /*
964 * Remember the highest logging level set by any channel in the
965 * logging config, so isc_log_doit() can quickly return if the
966 * message is too high to be logged by any channel.
967 */
968 if (channel->type != ISC_LOG_TONULL) {
969 if (lcfg->highest_level < channel->level) {
970 lcfg->highest_level = channel->level;
971 }
972 if (channel->level == ISC_LOG_DYNAMIC) {
973 lcfg->dynamic = true;
974 }
975 }
976 }
977
978 /*
979 * This would ideally be part of isc_log_registercategories(), except then
980 * that function would have to return isc_result_t instead of void.
981 */
982 static void
983 sync_channellist(isc_logconfig_t *lcfg) {
984 unsigned int bytes;
985 isc_log_t *lctx;
986 void *lists;
987
988 REQUIRE(VALID_CONFIG(lcfg));
989
990 lctx = lcfg->lctx;
991
992 REQUIRE(lctx->category_count != 0);
993
994 if (lctx->category_count == lcfg->channellist_count) {
995 return;
996 }
997
998 bytes = lctx->category_count * sizeof(ISC_LIST(isc_logchannellist_t));
999
1000 lists = isc_mem_get(lctx->mctx, bytes);
1001
1002 memset(lists, 0, bytes);
1003
1004 if (lcfg->channellist_count != 0) {
1005 bytes = lcfg->channellist_count *
1006 sizeof(ISC_LIST(isc_logchannellist_t));
1007 memmove(lists, lcfg->channellists, bytes);
1008 isc_mem_put(lctx->mctx, lcfg->channellists, bytes);
1009 }
1010
1011 lcfg->channellists = lists;
1012 lcfg->channellist_count = lctx->category_count;
1013 }
1014
1015 static void
1016 sync_highest_level(isc_log_t *lctx, isc_logconfig_t *lcfg) {
1017 atomic_store(&lctx->highest_level, lcfg->highest_level);
1018 atomic_store(&lctx->dynamic, lcfg->dynamic);
1019 }
1020
1021 static isc_result_t
1022 greatest_version(isc_logfile_t *file, int versions, int *greatestp) {
1023 char *bname, *digit_end;
1024 const char *dirname;
1025 int version, greatest = -1;
1026 size_t bnamelen;
1027 isc_dir_t dir;
1028 isc_result_t result;
1029 char sep = '/';
1030 #ifdef _WIN32
1031 char *bname2;
1032 #endif /* ifdef _WIN32 */
1033
1034 /*
1035 * It is safe to DE_CONST the file.name because it was copied
1036 * with isc_mem_strdup().
1037 */
1038 bname = strrchr(file->name, sep);
1039 #ifdef _WIN32
1040 bname2 = strrchr(file->name, '\\');
1041 if ((bname != NULL && bname2 != NULL && bname2 > bname) ||
1042 (bname == NULL && bname2 != NULL))
1043 {
1044 bname = bname2;
1045 sep = '\\';
1046 }
1047 #endif /* ifdef _WIN32 */
1048 if (bname != NULL) {
1049 *bname++ = '\0';
1050 dirname = file->name;
1051 } else {
1052 DE_CONST(file->name, bname);
1053 dirname = ".";
1054 }
1055 bnamelen = strlen(bname);
1056
1057 isc_dir_init(&dir);
1058 result = isc_dir_open(&dir, dirname);
1059
1060 /*
1061 * Replace the file separator if it was taken out.
1062 */
1063 if (bname != file->name) {
1064 *(bname - 1) = sep;
1065 }
1066
1067 /*
1068 * Return if the directory open failed.
1069 */
1070 if (result != ISC_R_SUCCESS) {
1071 return (result);
1072 }
1073
1074 while (isc_dir_read(&dir) == ISC_R_SUCCESS) {
1075 if (dir.entry.length > bnamelen &&
1076 strncmp(dir.entry.name, bname, bnamelen) == 0 &&
1077 dir.entry.name[bnamelen] == '.')
1078 {
1079 version = strtol(&dir.entry.name[bnamelen + 1],
1080 &digit_end, 10);
1081 /*
1082 * Remove any backup files that exceed versions.
1083 */
1084 if (*digit_end == '\0' && version >= versions) {
1085 result = isc_file_remove(dir.entry.name);
1086 if (result != ISC_R_SUCCESS &&
1087 result != ISC_R_FILENOTFOUND)
1088 {
1089 syslog(LOG_ERR,
1090 "unable to remove "
1091 "log file '%s': %s",
1092 dir.entry.name,
1093 isc_result_totext(result));
1094 }
1095 } else if (*digit_end == '\0' && version > greatest) {
1096 greatest = version;
1097 }
1098 }
1099 }
1100 isc_dir_close(&dir);
1101
1102 *greatestp = greatest;
1103
1104 return (ISC_R_SUCCESS);
1105 }
1106
1107 static void
1108 insert_sort(int64_t to_keep[], int64_t versions, int64_t version) {
1109 int i = 0;
1110 while (i < versions && version < to_keep[i]) {
1111 i++;
1112 }
1113 if (i == versions) {
1114 return;
1115 }
1116 if (i < versions - 1) {
1117 memmove(&to_keep[i + 1], &to_keep[i],
1118 sizeof(to_keep[0]) * (versions - i - 1));
1119 }
1120 to_keep[i] = version;
1121 }
1122
1123 static int64_t
1124 last_to_keep(int64_t versions, isc_dir_t *dirp, char *bname, size_t bnamelen) {
1125 int64_t to_keep[ISC_LOG_MAX_VERSIONS] = { 0 };
1126 int64_t version = 0;
1127
1128 if (versions <= 0) {
1129 return (INT64_MAX);
1130 }
1131
1132 if (versions > ISC_LOG_MAX_VERSIONS) {
1133 versions = ISC_LOG_MAX_VERSIONS;
1134 }
1135 /*
1136 * First we fill 'to_keep' structure using insertion sort
1137 */
1138 memset(to_keep, 0, sizeof(to_keep));
1139 while (isc_dir_read(dirp) == ISC_R_SUCCESS) {
1140 char *digit_end = NULL;
1141 char *ename = NULL;
1142
1143 if (dirp->entry.length <= bnamelen ||
1144 strncmp(dirp->entry.name, bname, bnamelen) != 0 ||
1145 dirp->entry.name[bnamelen] != '.')
1146 {
1147 continue;
1148 }
1149
1150 ename = &dirp->entry.name[bnamelen + 1];
1151 version = strtoull(ename, &digit_end, 10);
1152 if (*digit_end == '\0') {
1153 insert_sort(to_keep, versions, version);
1154 }
1155 }
1156
1157 isc_dir_reset(dirp);
1158
1159 /*
1160 * to_keep[versions - 1] is the last one we want to keep
1161 */
1162 return (to_keep[versions - 1]);
1163 }
1164
1165 static isc_result_t
1166 remove_old_tsversions(isc_logfile_t *file, int versions) {
1167 isc_result_t result;
1168 char *bname = NULL, *digit_end = NULL;
1169 const char *dirname = NULL;
1170 int64_t version, last = INT64_MAX;
1171 size_t bnamelen;
1172 isc_dir_t dir;
1173 char sep = '/';
1174 #ifdef _WIN32
1175 char *bname2;
1176 #endif /* ifdef _WIN32 */
1177 /*
1178 * It is safe to DE_CONST the file.name because it was copied
1179 * with isc_mem_strdup().
1180 */
1181 bname = strrchr(file->name, sep);
1182 #ifdef _WIN32
1183 bname2 = strrchr(file->name, '\\');
1184 if ((bname != NULL && bname2 != NULL && bname2 > bname) ||
1185 (bname == NULL && bname2 != NULL))
1186 {
1187 bname = bname2;
1188 sep = '\\';
1189 }
1190 #endif /* ifdef _WIN32 */
1191 if (bname != NULL) {
1192 *bname++ = '\0';
1193 dirname = file->name;
1194 } else {
1195 DE_CONST(file->name, bname);
1196 dirname = ".";
1197 }
1198 bnamelen = strlen(bname);
1199
1200 isc_dir_init(&dir);
1201 result = isc_dir_open(&dir, dirname);
1202
1203 /*
1204 * Replace the file separator if it was taken out.
1205 */
1206 if (bname != file->name) {
1207 *(bname - 1) = sep;
1208 }
1209
1210 /*
1211 * Return if the directory open failed.
1212 */
1213 if (result != ISC_R_SUCCESS) {
1214 return (result);
1215 }
1216
1217 last = last_to_keep(versions, &dir, bname, bnamelen);
1218
1219 /*
1220 * Then we remove all files that we don't want to_keep
1221 */
1222 while (isc_dir_read(&dir) == ISC_R_SUCCESS) {
1223 if (dir.entry.length > bnamelen &&
1224 strncmp(dir.entry.name, bname, bnamelen) == 0 &&
1225 dir.entry.name[bnamelen] == '.')
1226 {
1227 char *ename = &dir.entry.name[bnamelen + 1];
1228 version = strtoull(ename, &digit_end, 10);
1229 /*
1230 * Remove any backup files that exceed versions.
1231 */
1232 if (*digit_end == '\0' && version < last) {
1233 result = isc_file_remove(dir.entry.name);
1234 if (result != ISC_R_SUCCESS &&
1235 result != ISC_R_FILENOTFOUND)
1236 {
1237 syslog(LOG_ERR,
1238 "unable to remove "
1239 "log file '%s': %s",
1240 dir.entry.name,
1241 isc_result_totext(result));
1242 }
1243 }
1244 }
1245 }
1246
1247 isc_dir_close(&dir);
1248
1249 return (ISC_R_SUCCESS);
1250 }
1251
1252 static isc_result_t
1253 roll_increment(isc_logfile_t *file) {
1254 int i, n, greatest;
1255 char current[PATH_MAX + 1];
1256 char newpath[PATH_MAX + 1];
1257 const char *path;
1258 isc_result_t result = ISC_R_SUCCESS;
1259
1260 REQUIRE(file != NULL);
1261 REQUIRE(file->versions != 0);
1262
1263 path = file->name;
1264
1265 if (file->versions == ISC_LOG_ROLLINFINITE) {
1266 /*
1267 * Find the first missing entry in the log file sequence.
1268 */
1269 for (greatest = 0; greatest < INT_MAX; greatest++) {
1270 n = snprintf(current, sizeof(current), "%s.%u", path,
1271 (unsigned)greatest);
1272 if (n >= (int)sizeof(current) || n < 0 ||
1273 !isc_file_exists(current))
1274 {
1275 break;
1276 }
1277 }
1278 } else {
1279 /*
1280 * Get the largest existing version and remove any
1281 * version greater than the permitted version.
1282 */
1283 result = greatest_version(file, file->versions, &greatest);
1284 if (result != ISC_R_SUCCESS) {
1285 return (result);
1286 }
1287
1288 /*
1289 * Increment if greatest is not the actual maximum value.
1290 */
1291 if (greatest < file->versions - 1) {
1292 greatest++;
1293 }
1294 }
1295
1296 for (i = greatest; i > 0; i--) {
1297 result = ISC_R_SUCCESS;
1298 n = snprintf(current, sizeof(current), "%s.%u", path,
1299 (unsigned)(i - 1));
1300 if (n >= (int)sizeof(current) || n < 0) {
1301 result = ISC_R_NOSPACE;
1302 }
1303 if (result == ISC_R_SUCCESS) {
1304 n = snprintf(newpath, sizeof(newpath), "%s.%u", path,
1305 (unsigned)i);
1306 if (n >= (int)sizeof(newpath) || n < 0) {
1307 result = ISC_R_NOSPACE;
1308 }
1309 }
1310 if (result == ISC_R_SUCCESS) {
1311 result = isc_file_rename(current, newpath);
1312 }
1313 if (result != ISC_R_SUCCESS && result != ISC_R_FILENOTFOUND) {
1314 syslog(LOG_ERR,
1315 "unable to rename log file '%s.%u' to "
1316 "'%s.%u': %s",
1317 path, i - 1, path, i, isc_result_totext(result));
1318 }
1319 }
1320
1321 n = snprintf(newpath, sizeof(newpath), "%s.0", path);
1322 if (n >= (int)sizeof(newpath) || n < 0) {
1323 result = ISC_R_NOSPACE;
1324 } else {
1325 result = isc_file_rename(path, newpath);
1326 }
1327 if (result != ISC_R_SUCCESS && result != ISC_R_FILENOTFOUND) {
1328 syslog(LOG_ERR, "unable to rename log file '%s' to '%s.0': %s",
1329 path, path, isc_result_totext(result));
1330 }
1331
1332 return (ISC_R_SUCCESS);
1333 }
1334
1335 static isc_result_t
1336 roll_timestamp(isc_logfile_t *file) {
1337 int n;
1338 char newts[PATH_MAX + 1];
1339 char newpath[PATH_MAX + 1];
1340 const char *path;
1341 isc_time_t now;
1342 isc_result_t result = ISC_R_SUCCESS;
1343
1344 REQUIRE(file != NULL);
1345 REQUIRE(file->versions != 0);
1346
1347 path = file->name;
1348
1349 /*
1350 * First find all the logfiles and remove the oldest ones
1351 * Save one fewer than file->versions because we'll be renaming
1352 * the existing file to a timestamped version after this.
1353 */
1354 if (file->versions != ISC_LOG_ROLLINFINITE) {
1355 remove_old_tsversions(file, file->versions - 1);
1356 }
1357
1358 /* Then just rename the current logfile */
1359 isc_time_now(&now);
1360 isc_time_formatshorttimestamp(&now, newts, PATH_MAX + 1);
1361 n = snprintf(newpath, sizeof(newpath), "%s.%s", path, newts);
1362 if (n >= (int)sizeof(newpath) || n < 0) {
1363 result = ISC_R_NOSPACE;
1364 } else {
1365 result = isc_file_rename(path, newpath);
1366 }
1367 if (result != ISC_R_SUCCESS && result != ISC_R_FILENOTFOUND) {
1368 syslog(LOG_ERR, "unable to rename log file '%s' to '%s.0': %s",
1369 path, path, isc_result_totext(result));
1370 }
1371
1372 return (ISC_R_SUCCESS);
1373 }
1374
1375 isc_result_t
1376 isc_logfile_roll(isc_logfile_t *file) {
1377 isc_result_t result;
1378
1379 REQUIRE(file != NULL);
1380
1381 /*
1382 * Do nothing (not even excess version trimming) if ISC_LOG_ROLLNEVER
1383 * is specified. Apparently complete external control over the log
1384 * files is desired.
1385 */
1386 if (file->versions == ISC_LOG_ROLLNEVER) {
1387 return (ISC_R_SUCCESS);
1388 } else if (file->versions == 0) {
1389 result = isc_file_remove(file->name);
1390 if (result != ISC_R_SUCCESS && result != ISC_R_FILENOTFOUND) {
1391 syslog(LOG_ERR, "unable to remove log file '%s': %s",
1392 file->name, isc_result_totext(result));
1393 }
1394 return (ISC_R_SUCCESS);
1395 }
1396
1397 switch (file->suffix) {
1398 case isc_log_rollsuffix_increment:
1399 return (roll_increment(file));
1400 case isc_log_rollsuffix_timestamp:
1401 return (roll_timestamp(file));
1402 default:
1403 return (ISC_R_UNEXPECTED);
1404 }
1405 }
1406
1407 static isc_result_t
1408 isc_log_open(isc_logchannel_t *channel) {
1409 struct stat statbuf;
1410 bool regular_file;
1411 bool roll = false;
1412 isc_result_t result = ISC_R_SUCCESS;
1413 const char *path;
1414
1415 REQUIRE(channel->type == ISC_LOG_TOFILE);
1416 REQUIRE(FILE_STREAM(channel) == NULL);
1417
1418 path = FILE_NAME(channel);
1419
1420 REQUIRE(path != NULL && *path != '\0');
1421
1422 /*
1423 * Determine type of file; only regular files will be
1424 * version renamed, and only if the base file exists
1425 * and either has no size limit or has reached its size limit.
1426 */
1427 if (stat(path, &statbuf) == 0) {
1428 regular_file = S_ISREG(statbuf.st_mode) ? true : false;
1429 /* XXXDCL if not regular_file complain? */
1430 if ((FILE_MAXSIZE(channel) == 0 &&
1431 FILE_VERSIONS(channel) != ISC_LOG_ROLLNEVER) ||
1432 (FILE_MAXSIZE(channel) > 0 &&
1433 statbuf.st_size >= FILE_MAXSIZE(channel)))
1434 {
1435 roll = regular_file;
1436 }
1437 } else if (errno == ENOENT) {
1438 regular_file = true;
1439 POST(regular_file);
1440 } else {
1441 result = ISC_R_INVALIDFILE;
1442 }
1443
1444 /*
1445 * Version control.
1446 */
1447 if (result == ISC_R_SUCCESS && roll) {
1448 if (FILE_VERSIONS(channel) == ISC_LOG_ROLLNEVER) {
1449 return (ISC_R_MAXSIZE);
1450 }
1451 result = isc_logfile_roll(&channel->destination.file);
1452 if (result != ISC_R_SUCCESS) {
1453 if ((channel->flags & ISC_LOG_OPENERR) == 0) {
1454 syslog(LOG_ERR,
1455 "isc_log_open: isc_logfile_roll '%s' "
1456 "failed: %s",
1457 FILE_NAME(channel),
1458 isc_result_totext(result));
1459 channel->flags |= ISC_LOG_OPENERR;
1460 }
1461 return (result);
1462 }
1463 }
1464
1465 result = isc_stdio_open(path, "a", &FILE_STREAM(channel));
1466
1467 return (result);
1468 }
1469
1470 ISC_NO_SANITIZE_THREAD bool
1471 isc_log_wouldlog(isc_log_t *lctx, int level) {
1472 /*
1473 * Try to avoid locking the mutex for messages which can't
1474 * possibly be logged to any channels -- primarily debugging
1475 * messages that the debug level is not high enough to print.
1476 *
1477 * If the level is (mathematically) less than or equal to the
1478 * highest_level, or if there is a dynamic channel and the level is
1479 * less than or equal to the debug level, the main loop must be
1480 * entered to see if the message should really be output.
1481 */
1482 if (lctx == NULL) {
1483 return (false);
1484 }
1485
1486 int highest_level = atomic_load_acquire(&lctx->highest_level);
1487 if (level <= highest_level) {
1488 return (true);
1489 }
1490 if (atomic_load_acquire(&lctx->dynamic)) {
1491 int debug_level = atomic_load_acquire(&lctx->debug_level);
1492 if (level <= debug_level) {
1493 return (true);
1494 }
1495 }
1496
1497 return (false);
1498 }
1499
1500 static void
1501 isc_log_doit(isc_log_t *lctx, isc_logcategory_t *category,
1502 isc_logmodule_t *module, int level, bool write_once,
1503 const char *format, va_list args) {
1504 int syslog_level;
1505 const char *time_string;
1506 char local_time[64];
1507 char iso8601z_string[64];
1508 char iso8601l_string[64];
1509 char level_string[24] = { 0 };
1510 struct stat statbuf;
1511 bool matched = false;
1512 bool printtime, iso8601, utc, printtag, printcolon;
1513 bool printcategory, printmodule, printlevel, buffered;
1514 isc_logchannel_t *channel;
1515 isc_logchannellist_t *category_channels;
1516 isc_result_t result;
1517
1518 REQUIRE(lctx == NULL || VALID_CONTEXT(lctx));
1519 REQUIRE(category != NULL);
1520 REQUIRE(module != NULL);
1521 REQUIRE(level != ISC_LOG_DYNAMIC);
1522 REQUIRE(format != NULL);
1523
1524 /*
1525 * Programs can use libraries that use this logging code without
1526 * wanting to do any logging, thus the log context is allowed to
1527 * be non-existent.
1528 */
1529 if (lctx == NULL) {
1530 return;
1531 }
1532
1533 REQUIRE(category->id < lctx->category_count);
1534 REQUIRE(module->id < lctx->module_count);
1535
1536 if (!isc_log_wouldlog(lctx, level)) {
1537 return;
1538 }
1539
1540 local_time[0] = '\0';
1541 iso8601l_string[0] = '\0';
1542 iso8601z_string[0] = '\0';
1543
1544 RDLOCK(&lctx->lcfg_rwl);
1545 LOCK(&lctx->lock);
1546
1547 lctx->buffer[0] = '\0';
1548
1549 isc_logconfig_t *lcfg = lctx->logconfig;
1550
1551 category_channels = ISC_LIST_HEAD(lcfg->channellists[category->id]);
1552
1553 /*
1554 * XXXDCL add duplicate filtering? (To not write multiple times
1555 * to the same source via various channels).
1556 */
1557 do {
1558 /*
1559 * If the channel list end was reached and a match was
1560 * made, everything is finished.
1561 */
1562 if (category_channels == NULL && matched) {
1563 break;
1564 }
1565
1566 if (category_channels == NULL && !matched &&
1567 category_channels != ISC_LIST_HEAD(lcfg->channellists[0]))
1568 {
1569 /*
1570 * No category/module pair was explicitly
1571 * configured. Try the category named "default".
1572 */
1573 category_channels =
1574 ISC_LIST_HEAD(lcfg->channellists[0]);
1575 }
1576
1577 if (category_channels == NULL && !matched) {
1578 /*
1579 * No matching module was explicitly configured
1580 * for the category named "default". Use the
1581 * internal default channel.
1582 */
1583 category_channels = &default_channel;
1584 }
1585
1586 if (category_channels->module != NULL &&
1587 category_channels->module != module)
1588 {
1589 category_channels = ISC_LIST_NEXT(category_channels,
1590 link);
1591 continue;
1592 }
1593
1594 matched = true;
1595
1596 channel = category_channels->channel;
1597 category_channels = ISC_LIST_NEXT(category_channels, link);
1598
1599 int_fast32_t dlevel = atomic_load_acquire(&lctx->debug_level);
1600 if (((channel->flags & ISC_LOG_DEBUGONLY) != 0) && dlevel == 0)
1601 {
1602 continue;
1603 }
1604
1605 if (channel->level == ISC_LOG_DYNAMIC) {
1606 if (dlevel < level) {
1607 continue;
1608 }
1609 } else if (channel->level < level) {
1610 continue;
1611 }
1612
1613 if ((channel->flags & ISC_LOG_PRINTTIME) != 0 &&
1614 local_time[0] == '\0')
1615 {
1616 isc_time_t isctime;
1617
1618 TIME_NOW(&isctime);
1619
1620 isc_time_formattimestamp(&isctime, local_time,
1621 sizeof(local_time));
1622 isc_time_formatISO8601ms(&isctime, iso8601z_string,
1623 sizeof(iso8601z_string));
1624 isc_time_formatISO8601Lms(&isctime, iso8601l_string,
1625 sizeof(iso8601l_string));
1626 }
1627
1628 if ((channel->flags & ISC_LOG_PRINTLEVEL) != 0 &&
1629 level_string[0] == '\0')
1630 {
1631 if (level < ISC_LOG_CRITICAL) {
1632 snprintf(level_string, sizeof(level_string),
1633 "level %d: ", level);
1634 } else if (level > ISC_LOG_DYNAMIC) {
1635 snprintf(level_string, sizeof(level_string),
1636 "%s %d: ", log_level_strings[0],
1637 level);
1638 } else {
1639 snprintf(level_string, sizeof(level_string),
1640 "%s: ", log_level_strings[-level]);
1641 }
1642 }
1643
1644 /*
1645 * Only format the message once.
1646 */
1647 if (lctx->buffer[0] == '\0') {
1648 (void)vsnprintf(lctx->buffer, sizeof(lctx->buffer),
1649 format, args);
1650
1651 /*
1652 * Check for duplicates.
1653 */
1654 if (write_once) {
1655 isc_logmessage_t *message, *next;
1656 isc_time_t oldest;
1657 isc_interval_t interval;
1658 size_t size;
1659
1660 isc_interval_set(&interval,
1661 lcfg->duplicate_interval, 0);
1662
1663 /*
1664 * 'oldest' is the age of the oldest
1665 * messages which fall within the
1666 * duplicate_interval range.
1667 */
1668 TIME_NOW(&oldest);
1669 if (isc_time_subtract(&oldest, &interval,
1670 &oldest) != ISC_R_SUCCESS)
1671 {
1672 /*
1673 * Can't effectively do the
1674 * checking without having a
1675 * valid time.
1676 */
1677 message = NULL;
1678 } else {
1679 message = ISC_LIST_HEAD(lctx->messages);
1680 }
1681
1682 while (message != NULL) {
1683 if (isc_time_compare(&message->time,
1684 &oldest) < 0)
1685 {
1686 /*
1687 * This message is older
1688 * than the
1689 * duplicate_interval,
1690 * so it should be
1691 * dropped from the
1692 * history.
1693 *
1694 * Setting the interval
1695 * to be to be longer
1696 * will obviously not
1697 * cause the expired
1698 * message to spring
1699 * back into existence.
1700 */
1701 next = ISC_LIST_NEXT(message,
1702 link);
1703
1704 ISC_LIST_UNLINK(lctx->messages,
1705 message, link);
1706
1707 isc_mem_put(
1708 lctx->mctx, message,
1709 sizeof(*message) + 1 +
1710 strlen(message->text));
1711
1712 message = next;
1713 continue;
1714 }
1715
1716 /*
1717 * This message is in the
1718 * duplicate filtering interval
1719 * ...
1720 */
1721 if (strcmp(lctx->buffer,
1722 message->text) == 0)
1723 {
1724 /*
1725 * ... and it is a
1726 * duplicate. Unlock the
1727 * mutex and get the
1728 * hell out of Dodge.
1729 */
1730 goto unlock;
1731 }
1732
1733 message = ISC_LIST_NEXT(message, link);
1734 }
1735
1736 /*
1737 * It wasn't in the duplicate interval,
1738 * so add it to the message list.
1739 */
1740 size = sizeof(isc_logmessage_t) +
1741 strlen(lctx->buffer) + 1;
1742 message = isc_mem_get(lctx->mctx, size);
1743 message->text = (char *)(message + 1);
1744 size -= sizeof(isc_logmessage_t);
1745 strlcpy(message->text, lctx->buffer, size);
1746 TIME_NOW(&message->time);
1747 ISC_LINK_INIT(message, link);
1748 ISC_LIST_APPEND(lctx->messages, message, link);
1749 }
1750 }
1751
1752 utc = ((channel->flags & ISC_LOG_UTC) != 0);
1753 iso8601 = ((channel->flags & ISC_LOG_ISO8601) != 0);
1754 printtime = ((channel->flags & ISC_LOG_PRINTTIME) != 0);
1755 printtag = ((channel->flags &
1756 (ISC_LOG_PRINTTAG | ISC_LOG_PRINTPREFIX)) != 0 &&
1757 lcfg->tag != NULL);
1758 printcolon = ((channel->flags & ISC_LOG_PRINTTAG) != 0 &&
1759 lcfg->tag != NULL);
1760 printcategory = ((channel->flags & ISC_LOG_PRINTCATEGORY) != 0);
1761 printmodule = ((channel->flags & ISC_LOG_PRINTMODULE) != 0);
1762 printlevel = ((channel->flags & ISC_LOG_PRINTLEVEL) != 0);
1763 buffered = ((channel->flags & ISC_LOG_BUFFERED) != 0);
1764
1765 if (printtime) {
1766 if (iso8601) {
1767 if (utc) {
1768 time_string = iso8601z_string;
1769 } else {
1770 time_string = iso8601l_string;
1771 }
1772 } else {
1773 time_string = local_time;
1774 }
1775 } else {
1776 time_string = "";
1777 }
1778
1779 switch (channel->type) {
1780 case ISC_LOG_TOFILE:
1781 if (FILE_MAXREACHED(channel)) {
1782 /*
1783 * If the file can be rolled, OR
1784 * If the file no longer exists, OR
1785 * If the file is less than the maximum
1786 * size, (such as if it had been renamed
1787 * and a new one touched, or it was
1788 * truncated in place)
1789 * ... then close it to trigger
1790 * reopening.
1791 */
1792 if (FILE_VERSIONS(channel) !=
1793 ISC_LOG_ROLLNEVER ||
1794 (stat(FILE_NAME(channel), &statbuf) != 0 &&
1795 errno == ENOENT) ||
1796 statbuf.st_size < FILE_MAXSIZE(channel))
1797 {
1798 (void)fclose(FILE_STREAM(channel));
1799 FILE_STREAM(channel) = NULL;
1800 FILE_MAXREACHED(channel) = false;
1801 } else {
1802 /*
1803 * Eh, skip it.
1804 */
1805 break;
1806 }
1807 }
1808
1809 if (FILE_STREAM(channel) == NULL) {
1810 result = isc_log_open(channel);
1811 if (result != ISC_R_SUCCESS &&
1812 result != ISC_R_MAXSIZE &&
1813 (channel->flags & ISC_LOG_OPENERR) == 0)
1814 {
1815 syslog(LOG_ERR,
1816 "isc_log_open '%s' "
1817 "failed: %s",
1818 FILE_NAME(channel),
1819 isc_result_totext(result));
1820 channel->flags |= ISC_LOG_OPENERR;
1821 }
1822 if (result != ISC_R_SUCCESS) {
1823 break;
1824 }
1825 channel->flags &= ~ISC_LOG_OPENERR;
1826 }
1827 FALLTHROUGH;
1828
1829 case ISC_LOG_TOFILEDESC:
1830 fprintf(FILE_STREAM(channel), "%s%s%s%s%s%s%s%s%s%s\n",
1831 printtime ? time_string : "",
1832 printtime ? " " : "", printtag ? lcfg->tag : "",
1833 printcolon ? ": " : "",
1834 printcategory ? category->name : "",
1835 printcategory ? ": " : "",
1836 printmodule ? (module != NULL ? module->name
1837 : "no_module")
1838 : "",
1839 printmodule ? ": " : "",
1840 printlevel ? level_string : "", lctx->buffer);
1841
1842 if (!buffered) {
1843 fflush(FILE_STREAM(channel));
1844 }
1845
1846 /*
1847 * If the file now exceeds its maximum size
1848 * threshold, note it so that it will not be
1849 * logged to any more.
1850 */
1851 if (FILE_MAXSIZE(channel) > 0) {
1852 INSIST(channel->type == ISC_LOG_TOFILE);
1853
1854 /* XXXDCL NT fstat/fileno */
1855 /* XXXDCL complain if fstat fails? */
1856 if (fstat(fileno(FILE_STREAM(channel)),
1857 &statbuf) >= 0 &&
1858 statbuf.st_size > FILE_MAXSIZE(channel))
1859 {
1860 FILE_MAXREACHED(channel) = true;
1861 }
1862 }
1863
1864 break;
1865
1866 case ISC_LOG_TOSYSLOG:
1867 if (level > 0) {
1868 syslog_level = LOG_DEBUG;
1869 } else if (level < ISC_LOG_CRITICAL) {
1870 syslog_level = LOG_CRIT;
1871 } else {
1872 syslog_level = syslog_map[-level];
1873 }
1874
1875 (void)syslog(
1876 FACILITY(channel) | syslog_level,
1877 "%s%s%s%s%s%s%s%s%s%s",
1878 printtime ? time_string : "",
1879 printtime ? " " : "", printtag ? lcfg->tag : "",
1880 printcolon ? ": " : "",
1881 printcategory ? category->name : "",
1882 printcategory ? ": " : "",
1883 printmodule ? (module != NULL ? module->name
1884 : "no_module")
1885 : "",
1886 printmodule ? ": " : "",
1887 printlevel ? level_string : "", lctx->buffer);
1888 break;
1889
1890 case ISC_LOG_TONULL:
1891 break;
1892 }
1893 } while (1);
1894
1895 unlock:
1896 UNLOCK(&lctx->lock);
1897 RDUNLOCK(&lctx->lcfg_rwl);
1898 }
1899