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Diffstat (limited to 'src/knot/common/log.c')
| -rw-r--r-- | src/knot/common/log.c | 491 |
1 files changed, 491 insertions, 0 deletions
diff --git a/src/knot/common/log.c b/src/knot/common/log.c new file mode 100644 index 0000000..8bbdc51 --- /dev/null +++ b/src/knot/common/log.c @@ -0,0 +1,491 @@ +/* Copyright (C) 2021 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include <stdarg.h> +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <sys/time.h> +#include <time.h> +#include <urcu.h> + +#ifdef ENABLE_SYSTEMD +#define SD_JOURNAL_SUPPRESS_LOCATION 1 +#include <systemd/sd-journal.h> +#include <systemd/sd-daemon.h> +#endif + +#include "knot/common/log.h" +#include "libknot/libknot.h" +#include "contrib/ucw/lists.h" + +/*! Single log message buffer length (one line). */ +#define LOG_BUFLEN 512 +#define NULL_ZONE_STR "?" + +#ifdef ENABLE_SYSTEMD +int use_journal = 0; +#endif + +/*! Log context. */ +typedef struct { + size_t target_count; /*!< Log target count. */ + int *target; /*!< Log targets. */ + size_t file_count; /*!< Open files count. */ + FILE **file; /*!< Open files. */ + log_flag_t flags; /*!< Formatting flags. */ +} log_t; + +/*! Log singleton. */ +log_t *s_log = NULL; + +static bool log_isopen(void) +{ + return s_log != NULL; +} + +static void sink_free(log_t *log) +{ + if (log == NULL) { + return; + } + + // Close open log files. + for (int i = 0; i < log->file_count; ++i) { + fclose(log->file[i]); + } + free(log->target); + free(log->file); + free(log); +} + +/*! + * \brief Create logging targets respecting their canonical order. + * + * Facilities ordering: Syslog, Stderr, Stdout, File0... + */ +static log_t *sink_setup(size_t file_count) +{ + log_t *log = malloc(sizeof(*log)); + if (log == NULL) { + return NULL; + } + memset(log, 0, sizeof(*log)); + + // Reserve space for targets. + log->target_count = LOG_TARGET_FILE + file_count; + log->target = malloc(LOG_SOURCE_ANY * sizeof(int) * log->target_count); + if (!log->target) { + free(log); + return NULL; + } + memset(log->target, 0, LOG_SOURCE_ANY * sizeof(int) * log->target_count); + + // Reserve space for log files. + if (file_count > 0) { + log->file = malloc(sizeof(FILE *) * file_count); + if (!log->file) { + free(log->target); + free(log); + return NULL; + } + memset(log->file, 0, sizeof(FILE *) * file_count); + } + + return log; +} + +static void sink_publish(log_t *log) +{ + log_t **current_log = &s_log; + log_t *old_log = rcu_xchg_pointer(current_log, log); + synchronize_rcu(); + sink_free(old_log); +} + +static int *src_levels(log_t *log, log_target_t target, log_source_t src) +{ + assert(src < LOG_SOURCE_ANY); + return &log->target[LOG_SOURCE_ANY * target + src]; +} + +static void sink_levels_set(log_t *log, log_target_t target, log_source_t src, int levels) +{ + // Assign levels to the specified source. + if (src != LOG_SOURCE_ANY) { + *src_levels(log, target, src) = levels; + } else { + // ANY ~ set levels to all sources. + for (int i = 0; i < LOG_SOURCE_ANY; ++i) { + *src_levels(log, target, i) = levels; + } + } +} + +static void sink_levels_add(log_t *log, log_target_t target, log_source_t src, int levels) +{ + // Add levels to the specified source. + if (src != LOG_SOURCE_ANY) { + *src_levels(log, target, src) |= levels; + } else { + // ANY ~ add levels to all sources. + for (int i = 0; i < LOG_SOURCE_ANY; ++i) { + *src_levels(log, target, i) |= levels; + } + } +} + +void log_init(void) +{ + // Setup initial state. + int emask = LOG_MASK(LOG_CRIT) | LOG_MASK(LOG_ERR) | LOG_MASK(LOG_WARNING); + int imask = LOG_MASK(LOG_NOTICE) | LOG_MASK(LOG_INFO); + + // Publish base log sink. + log_t *log = sink_setup(0); + if (log == NULL) { + fprintf(stderr, "Failed to setup logging\n"); + return; + } + +#ifdef ENABLE_SYSTEMD + // Should only use the journal if system was booted with systemd. + use_journal = sd_booted(); +#endif + + sink_levels_set(log, LOG_TARGET_SYSLOG, LOG_SOURCE_ANY, emask); + sink_levels_set(log, LOG_TARGET_STDERR, LOG_SOURCE_ANY, emask); + sink_levels_set(log, LOG_TARGET_STDOUT, LOG_SOURCE_ANY, imask); + sink_publish(log); + + setlogmask(LOG_UPTO(LOG_DEBUG)); + openlog(PACKAGE_NAME, LOG_PID, LOG_DAEMON); +} + +void log_close(void) +{ + sink_publish(NULL); + + fflush(stdout); + fflush(stderr); + + closelog(); +} + +void log_flag_set(log_flag_t flag) +{ + if (log_isopen()) { + s_log->flags |= flag; + } +} + +void log_levels_set(log_target_t target, log_source_t src, int levels) +{ + if (log_isopen()) { + sink_levels_set(s_log, target, src, levels); + } +} + +void log_levels_add(log_target_t target, log_source_t src, int levels) +{ + if (log_isopen()) { + sink_levels_add(s_log, target, src, levels); + } +} + +static void emit_log_msg(int level, log_source_t src, const char *zone, + size_t zone_len, const char *msg, const char *param) +{ + log_t *log = s_log; + + // Syslog target. + if (*src_levels(log, LOG_TARGET_SYSLOG, src) & LOG_MASK(level)) { +#ifdef ENABLE_SYSTEMD + if (use_journal) { + char *zone_fmt = zone ? "ZONE=%.*s." : NULL; + sd_journal_send("PRIORITY=%d", level, + "MESSAGE=%s", msg, + zone_fmt, zone_len, zone, + param, NULL); + } else +#endif + { + syslog(level, "%s", msg); + } + } + + // Prefix date and time. + char tstr[LOG_BUFLEN] = { 0 }; + if (!(s_log->flags & LOG_FLAG_NOTIMESTAMP)) { + struct tm lt; + struct timeval tv; + gettimeofday(&tv, NULL); + time_t sec = tv.tv_sec; + if (localtime_r(&sec, <) != NULL) { + strftime(tstr, sizeof(tstr), KNOT_LOG_TIME_FORMAT " ", <); + } + } + + // Other log targets. + for (int i = LOG_TARGET_STDERR; i < LOG_TARGET_FILE + log->file_count; ++i) { + if (*src_levels(log, i, src) & LOG_MASK(level)) { + FILE *stream; + switch (i) { + case LOG_TARGET_STDERR: stream = stderr; break; + case LOG_TARGET_STDOUT: stream = stdout; break; + default: stream = log->file[i - LOG_TARGET_FILE]; break; + } + + // Print the message. + fprintf(stream, "%s%s\n", tstr, msg); + if (stream == stdout) { + fflush(stream); + } + } + } +} + +static const char *level_prefix(int level) +{ + switch (level) { + case LOG_DEBUG: return "debug"; + case LOG_INFO: return "info"; + case LOG_NOTICE: return "notice"; + case LOG_WARNING: return "warning"; + case LOG_ERR: return "error"; + case LOG_CRIT: return "critical"; + default: return NULL; + }; +} + +static int log_msg_add(char **write, size_t *capacity, const char *fmt, ...) +{ + va_list args; + va_start(args, fmt); + int written = vsnprintf(*write, *capacity, fmt, args); + va_end(args); + + if (written < 0 || written >= *capacity) { + return KNOT_ESPACE; + } + + *write += written; + *capacity -= written; + + return KNOT_EOK; +} + +static void log_msg_text(int level, log_source_t src, const char *zone, + const char *fmt, va_list args, const char *param) +{ + if (!log_isopen() || src == LOG_SOURCE_ANY) { + return; + } + + // Buffer for log message. + char buff[LOG_BUFLEN]; + char *write = buff; + size_t capacity = sizeof(buff); + + rcu_read_lock(); + + // Prefix error level. + if (level != LOG_INFO || !(s_log->flags & LOG_FLAG_NOINFO)) { + const char *prefix = level_prefix(level); + int ret = log_msg_add(&write, &capacity, "%s: ", prefix); + if (ret != KNOT_EOK) { + rcu_read_unlock(); + return; + } + } + + // Prefix zone name. + size_t zone_len = 0; + if (zone != NULL) { + zone_len = strlen(zone); + if (zone_len > 0 && zone[zone_len - 1] == '.') { + zone_len--; + } + + int ret = log_msg_add(&write, &capacity, "[%.*s.] ", (int)zone_len, zone); + if (ret != KNOT_EOK) { + rcu_read_unlock(); + return; + } + } + + // Compile log message. + int ret = vsnprintf(write, capacity, fmt, args); + if (ret >= 0) { + // Send to logging targets. + emit_log_msg(level, src, zone, zone_len, buff, param); + } + + rcu_read_unlock(); +} + +void log_fmt(int priority, log_source_t src, const char *fmt, ...) +{ + va_list args; + va_start(args, fmt); + log_msg_text(priority, src, NULL, fmt, args, NULL); + va_end(args); +} + +void log_fmt_zone(int priority, log_source_t src, const knot_dname_t *zone, + const char *param, const char *fmt, ...) +{ + knot_dname_txt_storage_t buff; + char *zone_str = knot_dname_to_str(buff, zone, sizeof(buff)); + if (zone_str == NULL) { + zone_str = NULL_ZONE_STR; + } + + va_list args; + va_start(args, fmt); + log_msg_text(priority, src, zone_str, fmt, args, param); + va_end(args); +} + +void log_fmt_zone_str(int priority, log_source_t src, const char *zone, + const char *fmt, ...) +{ + if (zone == NULL) { + zone = NULL_ZONE_STR; + } + + va_list args; + va_start(args, fmt); + log_msg_text(priority, src, zone, fmt, args, NULL); + va_end(args); +} + +int log_update_privileges(int uid, int gid) +{ + if (!log_isopen()) { + return KNOT_EOK; + } + + for (int i = 0; i < s_log->file_count; ++i) { + if (fchown(fileno(s_log->file[i]), uid, gid) < 0) { + log_error("failed to change log file owner"); + } + } + + return KNOT_EOK; +} + +static log_target_t get_logtype(const char *logname) +{ + assert(logname); + + if (strcasecmp(logname, "syslog") == 0) { + return LOG_TARGET_SYSLOG; + } else if (strcasecmp(logname, "stderr") == 0) { + return LOG_TARGET_STDERR; + } else if (strcasecmp(logname, "stdout") == 0) { + return LOG_TARGET_STDOUT; + } else { + return LOG_TARGET_FILE; + } +} + +static int log_open_file(log_t *log, const char *filename) +{ + assert(LOG_TARGET_FILE + log->file_count < log->target_count); + + // Open the file. + log->file[log->file_count] = fopen(filename, "a"); + if (log->file[log->file_count] == NULL) { + return knot_map_errno(); + } + + // Disable buffering. + setvbuf(log->file[log->file_count], NULL, _IONBF, 0); + + return LOG_TARGET_FILE + log->file_count++; +} + +void log_reconfigure(conf_t *conf) +{ + // Use defaults if no 'log' section is configured. + if (conf_id_count(conf, C_LOG) == 0) { + log_close(); + log_init(); + return; + } + + // Find maximum log target id. + unsigned files = 0; + for (conf_iter_t iter = conf_iter(conf, C_LOG); iter.code == KNOT_EOK; + conf_iter_next(conf, &iter)) { + conf_val_t id = conf_iter_id(conf, &iter); + if (get_logtype(conf_str(&id)) == LOG_TARGET_FILE) { + ++files; + } + } + + // Initialize logsystem. + log_t *log = sink_setup(files); + if (log == NULL) { + fprintf(stderr, "Failed to setup logging\n"); + return; + } + + // Setup logs. + for (conf_iter_t iter = conf_iter(conf, C_LOG); iter.code == KNOT_EOK; + conf_iter_next(conf, &iter)) { + conf_val_t id = conf_iter_id(conf, &iter); + const char *logname = conf_str(&id); + + // Get target. + int target = get_logtype(logname); + if (target == LOG_TARGET_FILE) { + target = log_open_file(log, logname); + if (target < 0) { + log_error("failed to open log, file '%s' (%s)", + logname, knot_strerror(target)); + continue; + } + } + + conf_val_t levels_val; + unsigned levels; + + // Set SERVER logging. + levels_val = conf_id_get(conf, C_LOG, C_SERVER, &id); + levels = conf_opt(&levels_val); + sink_levels_add(log, target, LOG_SOURCE_SERVER, levels); + + // Set CONTROL logging. + levels_val = conf_id_get(conf, C_LOG, C_CTL, &id); + levels = conf_opt(&levels_val); + sink_levels_add(log, target, LOG_SOURCE_CONTROL, levels); + + // Set ZONE logging. + levels_val = conf_id_get(conf, C_LOG, C_ZONE, &id); + levels = conf_opt(&levels_val); + sink_levels_add(log, target, LOG_SOURCE_ZONE, levels); + + // Set ANY logging. + levels_val = conf_id_get(conf, C_LOG, C_ANY, &id); + levels = conf_opt(&levels_val); + sink_levels_add(log, target, LOG_SOURCE_ANY, levels); + } + + sink_publish(log); +} |