2 * Copyright (c) 2016, Samsung Electronics Co., Ltd. All rights reserved.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
21 #include "logger_internal.h"
22 #include "logger_privileges.h"
23 #include "subreader_file.h"
24 #include "subreader_metrics.h"
25 #include "subreader_memory.h"
29 #include <dynamic_config.h>
30 #include <qos_defaults.h>
33 * @addtogroup DLOG_IMPLEMENTATION
35 * @defgroup DLOG_LOGGER Logger
36 * @brief Logger daemon
37 * @details The logger is the core component of the logging framework. It is responsible for collecting, processing and exposing logs.
41 /** global state when logger is not interrupted by any handled signals */
42 static volatile sig_atomic_t g_logger_run = 1;
44 static const int DEFAULT_EPOLL_TIME_MS = 1000;
46 static const int DEFAULT_LAZY_POLLING_TOTAL_MS = 0;
47 static const int DEFAULT_LAZY_POLLING_SLEEP_MS = 1000;
49 static const int S_TO_MS = 1000;
50 static const int MS_TO_NS = 1000000;
52 struct backend_data g_backend = {};
54 static void reader_logger_free(void *ptr, void *user_data)
56 struct reader_logger *reader = (struct reader_logger *)ptr;
58 reader_free(&reader->common);
61 // TODO: Consider inlining struct now_t everywhere
62 int get_now(struct now_t *now)
64 if (clock_gettime(CLOCK_MONOTONIC, &now->mono))
66 if (clock_gettime(CLOCK_REALTIME, &now->real))
72 * @brief FD limit handler
73 * @details Checks whether the FD limit was reached and leaves logs about it if so
74 * @param[in] server The logger server
75 * @param[in] err errno from the call that failed to create an FD
77 void check_if_fd_limit_reached(struct logger *server, int err)
81 if (err != ENFILE && err != EMFILE)
84 printf("ERROR: dlog_logger fd limit reached!\n");
86 /* pick one representative buffer to send the log to;
87 * no point spamming all the buffers, especially since
88 * default dlogutil invocations display 3 buffers so
89 * it would appear multiple times */
90 struct log_buffer *const buf = server->buffers[LOG_ID_MAIN];
94 struct dlogutil_entry_with_msg entry;
95 create_pipe_message(&entry,
96 DLOG_FATAL, /* not really FATAL, but since we're at the FD limit
97 * there are thousands of logging programs so this one
98 * would likely get lost in the flood since developers
99 * tend to overuse ERROR (and FATAL is the one above) */
101 "\x1b[31m DLOG DAEMON FD LIMIT REACHED \x1b[0m" // make it stand out
105 int r = get_now(&now);
108 set_pipe_message_sent_timestamp((struct pipe_logger_entry *) &entry, &now.mono, &now.real);
110 if (buffer_append(&entry.header, buf))
111 printf("ERROR: not enough memory either, please check platform settings as the daemon is seriously resource-starved!\n");
114 void flush_logfile_timely(struct log_file *file, struct timespec ts, int flush_time)
116 if (file->buffer.position > 0) {
117 if (ts.tv_sec - file->buffer.oldest_log.tv_sec +
118 (ts.tv_nsec > file->buffer.oldest_log.tv_nsec ? 1 : 0) >
124 void reader_pipe_notify_losing_log(const dlogutil_entry_s *le, void *reader_)
126 struct reader_pipe *reader = (struct reader_pipe *) reader_;
129 reader_pipe_print_out_single_log(reader, (dlogutil_entry_s *)le);
133 * @brief Add reader to log buffer
134 * @details Adds a reader to the log buffers reader list
135 * @param[in] log_buffer The buffer whither to add the reader
136 * @param[in] reader The reader to add to the buffer
137 * @return 0 on success, -ENOMEM on memory allocation error
139 int add_buffer_reader(struct log_buffer *buffer, struct reader_pipe *reader)
144 reader->log_storage_reader_ptr = log_storage_new_reader(buffer->log_storage_ptr,
145 reader->is_dumping, reader->monitor, reader_pipe_notify_losing_log, reader);
147 if (!reader->log_storage_reader_ptr)
150 return list_add(&buffer->readers_pipe, reader) ? 0 : -ENOMEM;
153 static int add_reader_common(struct logger *server, struct reader_common *reader)
158 if (reader->fd_entity_sink.fd >= 0) {
159 /* Readers who write to file have no sink FD entity (or, strictly
160 * speaking, they do have one but it is not filled) since a file
161 * is not eligible to be added to epoll. However, the entity primarily
162 * serves to handle pipes getting clogged mid-write (which cannot
163 * happen for files) and is not involved in starting a write,
164 * which is handled by the source FD entity, not sink (and which is
165 * also done periodically for all readers anyway regardless
166 * of whether they've been added to epoll or not). The other use
167 * case for epoll - the one where connection FDs leak for unused
168 * buffers - is not a problem here because the daemon is not
169 * supposed to ever stop writing to files. */
171 int r = add_fd_entity(&server->epoll_common, &reader->fd_entity_sink);
179 int add_reader_pipe(struct logger *server, struct reader_pipe *reader)
184 int ret = add_reader_common(server, &reader->common);
188 ret = add_buffer_reader(reader->buf_ptr, reader);
189 if (ret < 0 && reader->common.fd_entity_sink.fd >= 0)
190 remove_fd_entity(&server->epoll_common, &reader->common.fd_entity_sink);
195 int add_reader_memory(struct logger *server, struct reader_memory *reader)
200 int ret = add_reader_common(server, &reader->common);
204 // `readers_logger` actually accepts any readers
205 if (!list_add(&server->readers_logger, reader)) {
206 if (reader->common.fd_entity_sink.fd >= 0)
207 remove_fd_entity(&server->epoll_common, &reader->common.fd_entity_sink);
215 /* This really belongs to the UNIT_TEST block at the bottom since it is only used
216 * by a function living there, but has not been moved there to keep patches small
217 * and because this function is going to be removed soon in an upcoming patch. */
219 static int add_reader_logger(struct logger *server, struct reader_logger *reader)
224 int ret = add_reader_common(server, &reader->common);
228 assert(reader->common.fd_entity_source.fd >= 0);
229 ret = add_fd_entity(&server->epoll_common, &reader->common.fd_entity_source);
233 if (!list_add(&server->readers_logger, reader)) {
234 remove_fd_entity(&server->epoll_common, &reader->common.fd_entity_source);
242 if (reader->common.fd_entity_sink.fd >= 0)
243 remove_fd_entity(&server->epoll_common, &reader->common.fd_entity_sink);
249 int create_fifo_fds(struct logger *server, int pipe_fd[2], int flags, bool dump)
251 int ret = get_nonblocking_fifo(pipe_fd, flags);
255 /* Speed up dumping dlogutils by increasing their pipe size,
256 * as otherwise this pipe's size becomes a major bottleneck.
258 * Continuous connections don't really care if the initial
259 * burst of "historic" logs is slow and the following flow
260 * of logs is just fine with a small pipe. Meanwhile they
261 * live for a long time during which they would take away
262 * from the valuable total pipe size. */
264 if (fcntl(pipe_fd[1], F_SETPIPE_SZ, DUMPING_READER_PIPE_SIZE) < 0) {
265 /* Ignore; this is just a performance optimisation
266 * and doesn't affect functionality so while errors
267 * are worrisome they not a big deal or something
268 * we can do anything about, at any rate. */
274 static int create_memory_subreader_for_common(struct dlogutil_line_params *params, struct reader_common *reader, struct logger *server)
276 struct log_compressed_storage *storage = log_compressed_storage_create(params->file.rotate_size_kbytes * 1024, params->compression, params->mem_algo);
280 list_add(&server->compressed_memories, storage);
282 return reader_add_subreader_memory(reader, params->filter, storage);
285 static int create_memory_subreader_from_dlogutil_line(struct dlogutil_line_params *params, struct logger *server)
288 assert(params->compression);
290 if (params->file_path) // We're writing to memory, not to file
293 if (params->buf_id == LOG_ID_INVALID)
296 struct reader_logger *const reader = g_backend.logger_readers[params->buf_id];
300 return create_memory_subreader_for_common(params, &reader->common, server);
303 static int create_logger_subreader_from_dlogutil_line(struct dlogutil_line_params *params)
306 assert(!params->compression);
308 if (params->file_path) {
309 int retval = logfile_set_path(¶ms->file, params->file_path);
313 retval = logfile_open(¶ms->file);
318 if (params->buf_id == LOG_ID_INVALID)
321 if (params->file.path == NULL)
324 struct reader_logger *const reader = g_backend.logger_readers[params->buf_id];
328 return reader_add_subreader_file(&reader->common, params->filter, ¶ms->file, DLOGUTIL_SORT_SENT_REAL);
331 static int create_reader_pipe_from_dlogutil_line(struct dlogutil_line_params *params, struct logger *server, struct reader_pipe **rd)
336 __attribute__((cleanup(reader_free_ptr))) struct reader_pipe *reader = NULL;
339 if (params->file_path) {
340 retval = logfile_set_path(¶ms->file, params->file_path);
344 retval = logfile_open(¶ms->file);
349 if (params->buf_id == LOG_ID_INVALID)
352 if ((params->file.path == NULL && !params->compression)
353 || (params->file.path != NULL && params->compression))
356 retval = reader_pipe_init(&reader, params->buf_id, server, params->monitor, params->is_dumping);
360 if (params->file.path == NULL) {
361 assert(params->compression);
362 retval = create_memory_subreader_for_common(params, &reader->common, server);
366 /* FIXME: in theory these could be added independently (1 reader 2 subs),
367 * but so far that has not been needed and it sounds too fragile to do in haste.
368 * Keep in mind the reader only has one sink FD entity though, so unless
369 * that is rewritten, there can be only one sub with poll-dependent output. */
370 assert(!params->compression);
371 retval = reader_add_subreader_file(&reader->common, params->filter, ¶ms->file, server->buffers[params->buf_id]->sort_by);
383 * @brief Service a socket request
384 * @details Handle a socket request
385 * @param[in] server The logger server
386 * @param[in] wr The writer who sent the request
387 * @param[in] event The event containing the request
388 * @return 0 on success, else -errno
390 int service_writer_socket(struct logger *server, struct writer *wr, struct epoll_event *event)
395 struct dlog_control_msg *const msg = (struct dlog_control_msg *) wr->buffer;
398 if (event->events & EPOLLIN)
399 r = read(wr->fd_entity.fd, wr->buffer + wr->readed, sizeof wr->buffer - wr->readed);
401 if ((r == 0 || r == -1) && event->events & EPOLLHUP)
408 /* The socket is SOCK_STREAM (see `listen_fd_create`), so one message
409 * could be split into chunks returned across multiple read() calls. */
410 if (wr->readed < sizeof(msg->length)
411 || wr->readed < msg->length)
412 goto dont_process_yet_and_read_more_data;
414 assert(wr->service_socket);
415 r = wr->service_socket(server, wr, msg);
419 dont_process_yet_and_read_more_data:
420 r = read(wr->fd_entity.fd, wr->buffer + wr->readed, sizeof wr->buffer - wr->readed);
421 } while (r > 0 || ((wr->readed >= sizeof(msg->length) && wr->readed >= msg->length)));
423 return (r >= 0 || errno == EAGAIN) ? 0 : r;
427 * @brief Service /dev/kmsg
428 * @details Read from the /dev/kmsg device
429 * @param[in] server The logger server
430 * @param[in] wr The writer who sent the request
431 * @param[in] event The relevant event
432 * @return 0 on success, else -errno
434 int service_writer_kmsg(struct logger *server, struct writer *wr, struct epoll_event *event)
437 if (event->events & EPOLLHUP)
439 if (!(event->events & EPOLLIN))
442 /* The KMSG device returns just 1 log per read() so it is done in a loop.
443 * In theory this could starve everything else out if logs appeared faster
444 * than the daemon could process them, which would then necessitate some
445 * sort of throttling. In practice, KMSG doesn't really get flooded with
446 * logs the same way Android Logger devices are so the throttling is mostly
447 * there because we get it for free anyway and consistency doesn't hurt. */
449 int max_loop_iterations = g_backend.logger_device_throttling[LOG_ID_KMSG];
450 while (max_loop_iterations--) {
451 int r = read(wr->fd_entity.fd, wr->buffer, sizeof wr->buffer - 1);
453 if (r == -1 && (errno == EAGAIN || errno == EPIPE))
455 else if ((r == 0 || r == -1) && event->events & EPOLLHUP)
462 wr->buffer[r] = '\0';
463 struct dlogutil_entry_with_msg lem;
464 if (parse_kmsg_message(wr->buffer, &lem, r)) {
465 // don't signal an error: KMSG writer is too important to remove; besides, it would not get fixed that way.
473 add_recv_timestamp(&lem.header, now);
475 r = buffer_append(&lem.header, wr->buf_ptr);
483 static void service_reader_common(void *ptr, void *user_data)
485 struct reader_common *reader = (struct reader_common *)ptr;
486 struct logger *logger = (struct logger *)user_data;
492 int r = get_now(&now);
498 r = reader->service_reader(reader, now);
504 /* `service_reader()` returns -1 if everything was flushed, or 0 if
505 * a mild error happened that can be recovered from simply by waiting,
506 * the prime example being the pipe getting clogged. As soon as the
507 * reader is available again, we'd like to know about it to ensure
508 * logs are flushed as quickly as possible, which is why the EPOLLOUT.
510 * On the other hand, we don't want to remove readers from epoll even
511 * if they successfully flushed and have no logs to wait for. Consider
512 * the case where a buffer is unused (for example through libdlog's
513 * buffer disabling feature). If we relied on receiving an error on
514 * calling `write()` to learn that the connection had been closed,
515 * we would never learn about it because there would be no incoming
516 * logs to trigger the flush and so any FDs representing connections
517 * to such buffer would leak until a log finally arrived (which could
518 * be never). This is why waiting is also done on EPOLLHUP. */
519 if (modify_fd_entity(&logger->epoll_common, &reader->fd_entity_sink, (r == 0) ? EPOLLOUT : EPOLLHUP) < 0) {
520 /* ignore, can't really happen and it's not
521 * like we can do anything about it either */
524 // Ditto, can't do much about it
525 (void) reader_flush(reader, now.mono, logger->buf_params.time);
529 * @brief Service syslog
530 * @details Read from the syslog socket
531 * @param[in] server The logger server
532 * @param[in] wr The writer who sent the request
533 * @param[in] event The relevant event
534 * @return 0 on success, else -errno
536 int service_writer_syslog(struct logger *server, struct writer *wr, struct epoll_event *event)
538 if (event->events & EPOLLHUP)
540 if (!(event->events & EPOLLIN))
543 int r = read(wr->fd_entity.fd, wr->buffer, sizeof wr->buffer - 1);
545 if (r == -1 && (errno == EAGAIN || errno == EPIPE))
547 else if ((r == 0 || r == -1) && event->events & EPOLLHUP)
554 wr->buffer[r] = '\0';
556 struct dlogutil_entry_with_msg lem;
557 if (parse_syslog_datagram(wr->buffer, r + 1, &lem.header)) {
558 /* don't return parse error as writers are removed then */
566 add_recv_timestamp(&lem.header, now);
568 return buffer_append(&lem.header, wr->buf_ptr);
572 * @brief Service all readers
573 * @details Update all readers with latest data
574 * @param[in] server The logger server
575 * @param[in] force_push Whether to force logs to be pushed to the readers
577 static void service_all_readers(struct logger *server)
579 for (int i = 0; i < LOG_ID_MAX; i++) {
580 struct log_buffer *const buffer = server->buffers[i];
584 list_foreach(buffer->readers_pipe, server, service_reader_common);
586 list_foreach(server->readers_logger, server, service_reader_common);
590 * @brief Add writer to server
591 * @details Adds a writer to the server's witers list and registers its event to epoll loop
592 * @param[in] l The server to add the writer to
593 * @param[in] writer The writer to add to the server and register its working_fd to epoll loop
595 void logger_add_writer(struct logger *l, struct writer *wr)
600 list_add(&l->writers, wr);
601 add_fd_entity(&l->epoll_common, &wr->fd_entity);
605 * @brief Create the logger server
606 * @details Allocate the logger server's auxiliary structures (buffers etc.)
607 * @param[in] data Initialisation data
608 * @param[out] l The logger server
609 * @return 0 on success, -errno on failure
614 int logger_create(struct logger_config_data *data, struct logger *l)
616 memset(l, 0, sizeof *l);
617 l->epoll_socket.fd = -1;
619 int r = epoll_metadata_initialize(&l->epoll_common);
622 r = epoll_metadata_initialize(&l->epoll_socket);
626 l->epolltime = data->epoll_time;
628 l->buf_params = data->buf_params;
634 l->qos->log_metrics = metrics_create();
635 if (!l->qos->log_metrics)
639 // Check if the daemon is being launched for the first time since reboot
641 if (data->first_time_file_path) {
642 int fd = open(data->first_time_file_path, O_CREAT | O_EXCL | O_RDONLY, 0644);
653 // If no path, assume first time
656 if (g_backend.use_logger_by_default)
657 for (log_id_t id = 0; id < LOG_ID_MAX; ++id) {
658 if (!is_core_buffer(id))
661 int r = reader_logger_init(g_backend.logger_readers + id, id, l, !first_time);
664 if (!g_backend.logger_readers[id])
668 r = reader_add_subreader_metrics(&g_backend.logger_readers[id]->common, l->qos);
670 reader_free(&g_backend.logger_readers[id]->common);
671 g_backend.logger_readers[id] = NULL;
676 /* The reader is not yet complete; later in `finalize_init`
677 * it will receive further readers and be added to epoll
678 * or alternatively get culled if it gets no sub-readers. */
681 for (log_id_t id = 0; id < LOG_ID_MAX; id++)
682 if (data->is_buffer_enabled[id]) {
683 int r = buffer_create(&l->buffers[id], id, data->buffers + id);
688 for (log_id_t id = 0; id < LOG_ID_MAX; id++)
689 if (l->buffers[id]) {
690 add_fd_entity(&l->epoll_common, &l->buffers[id]->sock_ctl.fd_entity);
691 add_fd_entity(&l->epoll_common, &l->buffers[id]->sock_conn.fd_entity);
693 add_fd_entity(&l->epoll_socket, &l->buffers[id]->sock_ctl.fd_entity);
694 add_fd_entity(&l->epoll_socket, &l->buffers[id]->sock_conn.fd_entity);
697 /* TODO: make writers creation optional/configurable */
698 int (*writers_factories[LOG_ID_MAX])(struct writer **writer, struct log_buffer *log_buf) = {
699 [LOG_ID_KMSG] = create_kmsg_writer,
700 [LOG_ID_SYSLOG] = create_syslog_writer,
702 for (unsigned u = 0; u < NELEMS(writers_factories); ++u)
703 if (writers_factories[u] && data->is_buffer_enabled[u]) {
705 int r = writers_factories[u](&wr, l->buffers[u]);
709 logger_add_writer(l, wr);
717 * @details Deallocate the logger and its auxiliary structures
718 * @param[in] l The logger server
723 void logger_free(struct logger *l)
727 list_foreach(l->writers, l, foreach_writer_free);
728 list_foreach(l->readers_logger, l, reader_logger_free);
731 for (j = 0; j < LOG_ID_MAX; j++)
733 buffer_free(l->buffers[j]);
735 epoll_metadata_destroy(&l->epoll_common);
736 epoll_metadata_destroy(&l->epoll_socket);
742 * @brief Handle interrupting/terminating signals
743 * @details Clears global flag to stop main loop
744 * @param[in] signo signal number
746 static void handle_signals(int signo)
752 static void ensure_epoll_size(struct epoll_event **events, unsigned *size, unsigned wanted_size)
757 if (wanted_size <= *size)
760 typeof(*events) temp = realloc(*events, wanted_size * sizeof **events);
768 void dispatch_epoll_event(struct logger *server, struct epoll_event *event)
770 struct fd_entity *const entity = (struct fd_entity *) event->data.ptr;
771 assert(entity->dispatch_event);
772 entity->dispatch_event(server, event, entity->dispatch_data);
775 int handle_epoll_events(struct logger *server, struct epoll_metadata *metadata, int timeout)
777 ensure_epoll_size(&metadata->events, &metadata->events_size, metadata->cnt);
779 int nfds = epoll_wait(metadata->fd, metadata->events, metadata->events_size, timeout);
781 return errno == EINTR ? 0 : -errno;
783 for (int i = 0; i < nfds; i++)
784 dispatch_epoll_event(server, metadata->events + i);
789 int sleep_while_handling_socket(struct logger *server, struct epoll_metadata *metadata, int timeout)
791 struct timespec ts_start;
792 if (clock_gettime(CLOCK_MONOTONIC, &ts_start))
794 struct timespec ts_current;
797 int r = handle_epoll_events(server, metadata, timeout);
800 if (clock_gettime(CLOCK_MONOTONIC, &ts_current))
803 timeout > (ts_current.tv_sec - ts_start.tv_sec ) * S_TO_MS
804 + (ts_current.tv_nsec - ts_start.tv_nsec) / MS_TO_NS
810 void setup_signals(struct logger *server)
812 struct sigaction action = {
813 .sa_handler = handle_signals,
816 sigemptyset(&action.sa_mask);
818 static const int handled_signals[] = { SIGINT, SIGTERM };
819 for (unsigned u = 0; u < NELEMS(handled_signals); ++u)
820 sigaction(handled_signals[u], &action, NULL);
823 static bool do_logger_one_iteration(struct logger *server, bool *use_lazy_polling)
825 if (*use_lazy_polling)
826 sleep_while_handling_socket(server, &server->epoll_socket, g_backend.lazy_polling_sleep);
828 if (g_backend.lazy_polling_total > 0) {
829 g_backend.lazy_polling_total -= g_backend.lazy_polling_sleep;
830 *use_lazy_polling = (g_backend.lazy_polling_total > 0);
833 int r = handle_epoll_events(server, &server->epoll_common, server->epolltime * !*use_lazy_polling);
837 service_all_readers(server);
840 qos_periodic_check(server->qos);
847 * @details The main logging loop
848 * @param[in] server The logger server
849 * @return 0 on success, else -errno
854 int do_logger(struct logger *server)
856 setup_signals(server);
858 /* Note, negative values are applied here, but not in the check in
859 * the inner function. This leaves lazy polling enabled forever
860 * and is a feature. */
861 bool use_lazy_polling = (g_backend.lazy_polling_total != 0);
863 if (!do_logger_one_iteration(server, &use_lazy_polling))
866 /* ensure all logs are written no matter when the program was interrupted */
868 service_all_readers(server);
874 * @brief Prepare socket data
875 * @details Extracts initialisation data specific to each socket
876 * @param[in] conf Config database
877 * @param[out] data Socket init config data
878 * @param[in] buf_name The name of the buffer the socket belongs to
879 * @param[in] type The name of the buffer type
880 * @return 0 on success, -errno on failure
882 int prepare_socket_data(const struct log_config *conf, struct socket_config_data *data, char *buf_name, const char *type)
884 char conf_key[MAX_CONF_KEY_LEN];
887 r = snprintf(conf_key, MAX_CONF_KEY_LEN, "%s_%s_sock", buf_name, type);
890 const char * const path = log_config_get(conf, conf_key);
892 r = snprintf(conf_key, MAX_CONF_KEY_LEN, "%s_%s_sock_rights", buf_name, type);
895 const char * const permissions_str = log_config_get(conf, conf_key);
897 if (!permissions_str || !path)
900 data->permissions = parse_permissions(permissions_str);
901 if (data->permissions <= 0)
904 strncpy(data->path, path, MAX_CONF_VAL_LEN - 1);
910 * @brief Prepare buffer data
911 * @details Extracts data specific for each buffer
912 * @param[in] conf Config database
913 * @param[out] data Buffer init config data
914 * @param[in] buf_id Index of the buffer to work with
915 * @return 0 on success, -errno on failure
917 int prepare_buffer_data(const struct log_config *conf, struct buffer_config_data *data, log_id_t buf_id)
919 char * const buf_name = log_name_by_id(buf_id);
920 char * validity_check_ptr;
921 char conf_key[MAX_CONF_KEY_LEN];
924 r = prepare_socket_data(conf, &data->conn_socket, buf_name, "conn");
928 r = prepare_socket_data(conf, &data->ctl_socket, buf_name, "ctl");
932 r = snprintf(conf_key, MAX_CONF_KEY_LEN, "%s_size", buf_name);
936 const char * const size_str = log_config_get(conf, conf_key);
940 data->size = strtol(size_str, &validity_check_ptr, 10);
941 if (*validity_check_ptr)
950 * @brief Save logfile line
951 * @detail Saves logfile config line in user_data list
952 * @param[in] key Config entry key
953 * @param[in] value Config entry value
954 * @param[in] userdata Userdata
956 void save_logfile_config(char const *key, char const *value, void *userdata)
959 if (strncmp(key, CONF_PREFIX, sizeof CONF_PREFIX - 1))
962 struct logger_config_data *data = (struct logger_config_data *)userdata;
963 char *cmd = strdup(value);
965 list_add(&data->logfile_configs, cmd);
970 * @brief Initialize config data
971 * @param[out] The data structure to fill with initial values
973 void initialize_config_data(struct logger_config_data *data)
975 memset(data, 0, sizeof *data);
979 * @brief Prepare config data
980 * @details Extracts relevant config data for logger initialisation
981 * @param[out] data Parsed configuration
982 * @return 0 on success, -errno on failure
984 int prepare_config_data(struct logger_config_data *data)
988 struct log_config conf;
989 int ret = log_config_read(&conf);
993 const dlogutil_sorting_order_e sort_by = get_order_from_config(&conf);
995 int throttling_default = log_config_get_int(&conf, "logger_dev_throttling", LOGGER_DEVICE_THROTTLING_DEFAULT);
996 const char *const dynamic_config_dir = log_config_get(&conf, DYNAMIC_CONFIG_CONF_KEY);
998 const char * const backend = log_config_claim_backend(&conf);
1004 if (!strcmp(backend, "null")) {
1009 for (int i = 0; i < LOG_ID_MAX; i++) {
1010 char key[MAX_CONF_KEY_LEN];
1011 const int r = snprintf(key, sizeof key, "logger_dev_throttling_%s", log_name_by_id((log_id_t)i));
1015 g_backend.logger_device_throttling[i] = max_int(1, log_config_get_int(&conf, key, throttling_default));
1018 if (dynamic_config_dir && dynamic_config_dir[0] == '/') {
1019 data->dynamic_config_dir = strdup(dynamic_config_dir);
1020 if (!data->dynamic_config_dir) {
1025 data->dynamic_config_dir = NULL; // Technically unnecessary but no reason not to put it
1028 data->epoll_time = log_config_get_int(&conf, "epoll_time_ms", DEFAULT_EPOLL_TIME_MS);
1029 g_backend.lazy_polling_total = 0; // Android Logger backend only, read below
1031 struct qos_module qos = {0, };
1033 qos.file_path = (char *) log_config_get(&conf, "qos_file_path");
1034 qos.limit_duration = log_config_get_int(&conf, "qos_refresh_rate_s", DEFAULT_QOS_LIMIT_DURATION_S);
1035 qos.max_throughput = log_config_get_int(&conf, "qos_max_throughput_logs", DEFAULT_QOS_THROUGHPUT_LOGS);
1036 qos.threshold = log_config_get_int(&conf, "qos_threshold_logs", DEFAULT_QOS_THRESHOLD_LOGS);
1037 qos.threshold_reapply = log_config_get_int(&conf, "qos_threshold_reapply_logs", DEFAULT_QOS_THRESHOLD_REAPPLY_LOGS);
1038 qos.distribution_func = qos_get_distribution_func_by_name(log_config_get(&conf, "qos_method"));
1040 if (qos.threshold > 0
1041 && qos.max_throughput > 0
1042 && qos.file_path && strlen(qos.file_path) > 0) {
1043 data->qos = malloc(sizeof *data->qos);
1049 data->qos->file_path = strdup(qos.file_path);
1050 if (!data->qos->file_path) {
1056 const char *const first_time_file_path = log_config_get(&conf, "first_time_file_path");
1057 data->first_time_file_path = first_time_file_path ? strdup(first_time_file_path) : NULL;
1059 memset(data->is_buffer_enabled, 0, sizeof(data->is_buffer_enabled));
1060 if (!strcmp(backend, "pipe")) {
1061 data->is_buffer_enabled[LOG_ID_MAIN] =
1062 data->is_buffer_enabled[LOG_ID_RADIO] =
1063 data->is_buffer_enabled[LOG_ID_SYSTEM] =
1064 data->is_buffer_enabled[LOG_ID_APPS] = 1;
1065 g_backend.use_logger_by_default = false;
1066 } else if (!strcmp(backend, "logger")) {
1067 g_backend.use_logger_by_default = true;
1068 for (log_id_t buf_id = 0; buf_id < LOG_ID_MAX; ++buf_id) {
1069 const char *const logger_device = log_config_get(&conf, log_name_by_id(buf_id));
1071 strncpy(g_backend.logger_devices[buf_id], logger_device,
1072 NELEMS(g_backend.logger_devices[buf_id]) - 1);
1074 g_backend.lazy_polling_total = log_config_get_int(&conf, "lazy_polling_total_ms", DEFAULT_LAZY_POLLING_TOTAL_MS);
1075 g_backend.lazy_polling_sleep = log_config_get_int(&conf, "lazy_polling_sleep_ms", DEFAULT_LAZY_POLLING_SLEEP_MS);
1077 /* The total can be 0 (no lazy polling) or negative (infinite),
1078 * but the sleep length has to be positive. */
1079 if (g_backend.lazy_polling_sleep < 1)
1080 g_backend.lazy_polling_sleep = 1;
1082 } else if (!strcmp(backend, "zero-copy")) {
1083 /* HACK: This essentially skips reading the most important configuration fields
1084 * (buffer reading and persistent logs) while ensuring the variables are initialized.
1085 * This will result in daemon quitting. Hopefully we will either reenable some of these
1086 * in the future or at least make it exit more gracefully (TODO), but for now this is ok. */
1087 g_backend.use_logger_by_default = false;
1093 data->is_buffer_enabled[LOG_ID_KMSG] = log_config_get_boolean(&conf, "handle_kmsg", true);
1094 data->is_buffer_enabled[LOG_ID_SYSLOG] =
1095 dev_log_sock_get() >= 0 || log_config_get_boolean(&conf, "syslog_force", false);
1097 for (log_id_t buf_id = 0; buf_id < LOG_ID_MAX; ++buf_id) {
1098 if (data->is_buffer_enabled[buf_id]) {
1099 ret = prepare_buffer_data(&conf, data->buffers + buf_id, buf_id);
1102 data->buffers[buf_id].sort_by = sort_by;
1105 log_config_foreach(&conf, save_logfile_config, data);
1107 data->default_format = get_default_format_from_config(&conf);
1110 log_config_free(&conf);
1117 void free_config_data(struct logger_config_data *data)
1119 list_clear_free_contents(&data->logfile_configs);
1120 free(data->dynamic_config_dir);
1121 qos_free(data->qos);
1122 free(data->first_time_file_path);
1125 struct parse_logfile_config_data {
1126 struct logger *server;
1127 struct logger_config_data *data;
1131 * @brief Parse logfile line
1132 * @detail Parses a logfile config line
1133 * @param[in] key Config entry key
1134 * @param[in] value Config entry value
1135 * @param[in] userdata Userdata
1137 void parse_logfile_config(void *value, void *userdata)
1142 struct logger *server = ((struct parse_logfile_config_data *) userdata)->server;
1143 struct logger_config_data *data = ((struct parse_logfile_config_data *) userdata)->data;
1144 char *configline = (char *) value;
1146 __attribute__((cleanup(free_dlogutil_line_params))) struct dlogutil_line_params params;
1147 if (!initialize_dlogutil_line_params(¶ms, server->buf_params))
1150 get_dlogutil_line_params(configline, data->default_format, ¶ms);
1153 if (g_backend.use_logger_by_default && is_core_buffer(params.buf_id)) {
1154 r = params.compression
1155 ? create_memory_subreader_from_dlogutil_line(¶ms, server)
1156 : create_logger_subreader_from_dlogutil_line(¶ms)
1159 struct reader_pipe *reader = NULL;
1160 r = create_reader_pipe_from_dlogutil_line(¶ms, server, &reader);
1162 add_reader_pipe(server, reader);
1167 printf("Warning: unable to add logutil reader for provided configuration. Ignoring.\n"
1168 " Config line: %s\n"
1169 " Reason given: %m\n",
1177 * @details Prints basic usage tips
1179 static void help(void)
1181 printf("Usage: %s [options]\n"
1182 "\t-h Show this help\n"
1183 "\t-b N Set the size of the log buffer (in bytes)\n"
1184 "\t-t N Set time between writes to file (in seconds)\n",
1185 program_invocation_short_name);
1190 * @details Parses execution parameters of the program
1191 * @param[in] argc Argument count
1192 * @param[in] argv Argument values
1193 * @param[out] b Buffering parameters
1194 * @return 0 or 1 on success, else -errno. Nonzero if the program is to close.
1196 static int parse_args(int argc, char **argv, struct buf_params *b)
1198 b->time = BUF_PARAM_TIME_DEFAULT;
1199 b->bytes = BUF_PARAM_BYTES_DEFAULT;
1202 while ((option = getopt(argc, argv, "hb:t:")) != -1) {
1205 if (!isdigit(optarg[0]))
1207 b->time = clamp_int(atoi(optarg), BUF_PARAM_TIME_MIN, BUF_PARAM_TIME_MAX);
1210 if (!isdigit(optarg[0]))
1212 b->bytes = clamp_int(atoi(optarg), BUF_PARAM_BYTES_MIN, BUF_PARAM_BYTES_MAX);
1225 * @brief Finalize initialisation
1226 * @details Do misc stuff needed at the end of the initialisation
1227 * @param[in] data configuration dat to read logfiles config lines from
1228 * @param[in] server logger instance to configure
1229 * @return 0 on success, -errno on failure
1231 static int finalize_init(struct logger_config_data *data, struct logger *server)
1233 int r = sd_notify(0, "READY=1");
1237 //create files after resetting self privileges
1238 list_foreach(data->logfile_configs, &(struct parse_logfile_config_data) {
1241 }, parse_logfile_config);
1243 /* The above created subs for logger readers.
1244 * There is no way for them to gain more at
1245 * runtime, so this is the time to do some
1246 * processing that relies on subs being ready. */
1247 for (log_id_t id = 0; id < LOG_ID_MAX; ++id) {
1248 struct reader_logger *const reader = g_backend.logger_readers[id];
1252 if (reader->common.subs == NULL) {
1253 reader_free(&reader->common);
1254 g_backend.logger_readers[id] = NULL;
1258 r = add_reader_logger(server, reader);
1260 reader_free(&reader->common);
1261 g_backend.logger_readers[id] = NULL;
1269 static void precreate_logctl_file(struct logger_config_data *data)
1271 __attribute__((cleanup(free_ptr))) char *logctl_file_path = NULL;
1272 if (asprintf(&logctl_file_path, "%s/%s", data->dynamic_config_dir, DYNAMIC_CONFIG_FILENAME) < 0)
1273 // This is worrying but unimportant
1276 int fd = open(logctl_file_path, O_RDONLY | O_CREAT, 0644);
1278 // Again, no big deal
1284 bool early_termination(const struct logger_config_data *data, const struct logger *logger) {
1285 /* In order to check if the deamon will be doing nothing
1286 * and can quit instantaneously, we do three checks: */
1288 /* 1. We make sure that there are no Android Logger readers.
1289 * Note that an earlier function gets rid of any readers that
1290 * don't do anything (i.e. have no subs and no way to get them). */
1291 for (log_id_t id = 0; id < LOG_ID_MAX; ++id) {
1292 const struct reader_logger *const reader = g_backend.logger_readers[id];
1296 assert(reader->common.subs != NULL);
1300 /* 2. We make sure that no pipe-like buffer is enabled.
1301 * When the pipe backend is being used or pipe-like buffers
1302 * (i.e. KMSG, SYSLOG) are handled, the logger allocates space for them.
1303 * In this case, we cannot terminate even if the buffer is enabled
1304 * but unused at the moment, since it might be connected to
1305 * (for instance by dlogutil). */
1306 for (log_id_t id = 0; id < LOG_ID_MAX; id++)
1307 if (data->is_buffer_enabled[id])
1310 /* 3. We make sure that there are no writers.
1311 * In theory, previous checks are sufficient.
1312 * However, we do another check just to be sure
1313 * (since if there are writers, we shouldn't terminate).
1314 * Additionally, this could change in the future,
1315 * so let's hedge against someone forgetting that this function exists. */
1316 return logger->writers == NULL;
1321 * @return 0 on success, nonzero on failure
1322 * @retval 1 Configuration error
1323 * @retval 2 Runtime error
1325 int main(int argc, char **argv)
1329 signal(SIGPIPE, SIG_IGN);
1331 r = reset_self_privileges();
1334 printf("Unable to drop privileges to build-time defaults (%m). Exiting.\n");
1335 return DLOG_EXIT_ERR_RUNTIME;
1338 struct logger_config_data data;
1339 initialize_config_data(&data);
1341 if ((r = parse_args(argc, argv, &data.buf_params)) != 0) {
1345 return DLOG_EXIT_SUCCESS; // --help option
1348 printf("Unable to parse command line args (%m). Exiting.\n");
1349 return DLOG_EXIT_ERR_CONFIG;
1352 if ((r = prepare_config_data(&data)) != 0) {
1354 printf("Unable to prepare config (%m). Exiting.\n");
1355 return DLOG_EXIT_ERR_CONFIG;
1358 precreate_logctl_file(&data);
1360 struct logger server;
1361 if ((r = logger_create(&data, &server)) < 0) {
1363 printf("Unable to initialize logger with provided configuration (%m). Exiting.\n");
1364 ret = DLOG_EXIT_ERR_CONFIG;
1368 if ((r = finalize_init(&data, &server)) < 0) {
1370 printf("Unable to finalize initialisation (%m). Exiting.\n");
1371 ret = DLOG_EXIT_ERR_CONFIG;
1375 if (early_termination(&data, &server)) {
1376 printf("No work to do according to provided configuration. Exiting.\n");
1377 ret = DLOG_EXIT_SUCCESS;
1381 if ((r = do_logger(&server)) < 0) {
1383 printf("Runtime failure (%m). Exiting.\n");
1384 ret = DLOG_EXIT_ERR_RUNTIME;
1388 ret = DLOG_EXIT_SUCCESS;
1391 free_config_data(&data);
1392 logger_free(&server);