/* * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2015, 2016 Nicira, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include #include "openvswitch/vlog.h" #include #include #include #include #include #include #include #include #include #include #include #include #include "async-append.h" #include "coverage.h" #include "dirs.h" #include "openvswitch/dynamic-string.h" #include "openvswitch/ofpbuf.h" #include "ovs-thread.h" #include "sat-math.h" #include "socket-util.h" #include "svec.h" #include "syslog-direct.h" #include "syslog-libc.h" #include "syslog-null.h" #include "syslog-provider.h" #include "timeval.h" #include "unixctl.h" #include "util.h" VLOG_DEFINE_THIS_MODULE(vlog); /* ovs_assert() logs the assertion message, so using ovs_assert() in this * source file could cause recursion. */ #undef ovs_assert #define ovs_assert use_assert_instead_of_ovs_assert_in_this_module /* Name for each logging level. */ static const char *const level_names[VLL_N_LEVELS] = { #define VLOG_LEVEL(NAME, SYSLOG_LEVEL, RFC5424) #NAME, VLOG_LEVELS #undef VLOG_LEVEL }; /* Syslog value for each logging level. */ static const int syslog_levels[VLL_N_LEVELS] = { #define VLOG_LEVEL(NAME, SYSLOG_LEVEL, RFC5424) SYSLOG_LEVEL, VLOG_LEVELS #undef VLOG_LEVEL }; /* RFC 5424 defines specific values for each syslog level. Normally LOG_* use * the same values. Verify that in fact they're the same. If we get assertion * failures here then we need to define a separate rfc5424_levels[] array. */ #define VLOG_LEVEL(NAME, SYSLOG_LEVEL, RFC5424) \ BUILD_ASSERT_DECL(SYSLOG_LEVEL == RFC5424); VLOG_LEVELS #undef VLOG_LEVELS /* Similarly, RFC 5424 defines the local0 facility with the value ordinarily * used for LOG_LOCAL0. */ BUILD_ASSERT_DECL(LOG_LOCAL0 == (16 << 3)); /* Protects the 'pattern' in all "struct destination"s, so that a race between * changing and reading the pattern does not cause an access to freed * memory. */ static struct ovs_rwlock pattern_rwlock = OVS_RWLOCK_INITIALIZER; /* Information about each destination. */ struct destination { const char *name; /* Name. */ char *pattern OVS_GUARDED_BY(pattern_rwlock); /* Current pattern. */ bool default_pattern; /* Whether current pattern is the default. */ }; static struct destination destinations[VLF_N_DESTINATIONS] = { #define VLOG_DESTINATION(NAME, PATTERN) {#NAME, PATTERN, true}, VLOG_DESTINATIONS #undef VLOG_DESTINATION }; /* Sequence number for the message currently being composed. */ DEFINE_STATIC_PER_THREAD_DATA(unsigned int, msg_num, 0); /* VLF_FILE configuration. * * All of the following is protected by 'log_file_mutex', which nests inside * pattern_rwlock. */ static struct ovs_mutex log_file_mutex OVS_ACQ_AFTER(pattern_rwlock) = OVS_MUTEX_INITIALIZER; static char *log_file_name OVS_GUARDED_BY(log_file_mutex) = NULL; static int log_fd OVS_GUARDED_BY(log_file_mutex) = -1; static struct async_append *log_writer OVS_GUARDED_BY(log_file_mutex); static bool log_async OVS_GUARDED_BY(log_file_mutex); static struct syslogger *syslogger = NULL; /* The log modules. */ static struct ovs_list vlog_modules OVS_GUARDED_BY(log_file_mutex) = OVS_LIST_INITIALIZER(&vlog_modules); /* Syslog export configuration. */ static int syslog_fd OVS_GUARDED_BY(pattern_rwlock) = -1; /* Log facility configuration. */ static atomic_int log_facility = 0; /* Facility name and its value. */ struct vlog_facility { char *name; /* Name. */ unsigned int value; /* Facility associated with 'name'. */ }; static struct vlog_facility vlog_facilities[] = { {"kern", LOG_KERN}, {"user", LOG_USER}, {"mail", LOG_MAIL}, {"daemon", LOG_DAEMON}, {"auth", LOG_AUTH}, {"syslog", LOG_SYSLOG}, {"lpr", LOG_LPR}, {"news", LOG_NEWS}, {"uucp", LOG_UUCP}, {"clock", LOG_CRON}, {"ftp", LOG_FTP}, {"ntp", 12<<3}, {"audit", 13<<3}, {"alert", 14<<3}, {"clock2", 15<<3}, {"local0", LOG_LOCAL0}, {"local1", LOG_LOCAL1}, {"local2", LOG_LOCAL2}, {"local3", LOG_LOCAL3}, {"local4", LOG_LOCAL4}, {"local5", LOG_LOCAL5}, {"local6", LOG_LOCAL6}, {"local7", LOG_LOCAL7} }; static bool vlog_facility_exists(const char* facility, int *value); static void format_log_message(const struct vlog_module *, enum vlog_level, const char *pattern, const char *message, va_list, struct ds *) OVS_PRINTF_FORMAT(4, 0); /* Searches the 'n_names' in 'names'. Returns the index of a match for * 'target', or 'n_names' if no name matches. */ static size_t search_name_array(const char *target, const char *const *names, size_t n_names) { size_t i; for (i = 0; i < n_names; i++) { assert(names[i]); if (!strcasecmp(names[i], target)) { break; } } return i; } /* Returns the name for logging level 'level'. */ const char * vlog_get_level_name(enum vlog_level level) { assert(level < VLL_N_LEVELS); return level_names[level]; } /* Returns the logging level with the given 'name', or VLL_N_LEVELS if 'name' * is not the name of a logging level. */ enum vlog_level vlog_get_level_val(const char *name) { return search_name_array(name, level_names, ARRAY_SIZE(level_names)); } /* Returns the name for logging destination 'destination'. */ const char * vlog_get_destination_name(enum vlog_destination destination) { assert(destination < VLF_N_DESTINATIONS); return destinations[destination].name; } /* Returns the logging destination named 'name', or VLF_N_DESTINATIONS if * 'name' is not the name of a logging destination. */ enum vlog_destination vlog_get_destination_val(const char *name) { size_t i; for (i = 0; i < VLF_N_DESTINATIONS; i++) { if (!strcasecmp(destinations[i].name, name)) { break; } } return i; } void vlog_insert_module(struct ovs_list *vlog) { ovs_mutex_lock(&log_file_mutex); ovs_list_insert(&vlog_modules, vlog); ovs_mutex_unlock(&log_file_mutex); } /* Returns the name for logging module 'module'. */ const char * vlog_get_module_name(const struct vlog_module *module) { return module->name; } /* Returns the logging module named 'name', or NULL if 'name' is not the name * of a logging module. */ struct vlog_module * vlog_module_from_name(const char *name) { struct vlog_module *mp; ovs_mutex_lock(&log_file_mutex); LIST_FOR_EACH (mp, list, &vlog_modules) { if (!strcasecmp(name, mp->name)) { ovs_mutex_unlock(&log_file_mutex); return mp; } } ovs_mutex_unlock(&log_file_mutex); return NULL; } /* Returns the current logging level for the given 'module' and * 'destination'. */ enum vlog_level vlog_get_level(const struct vlog_module *module, enum vlog_destination destination) { assert(destination < VLF_N_DESTINATIONS); return module->levels[destination]; } static void update_min_level(struct vlog_module *module) OVS_REQUIRES(log_file_mutex) { enum vlog_destination destination; module->min_level = VLL_OFF; for (destination = 0; destination < VLF_N_DESTINATIONS; destination++) { if (log_fd >= 0 || destination != VLF_FILE) { enum vlog_level level = module->levels[destination]; if (level > module->min_level) { module->min_level = level; } } } } static void set_destination_level(enum vlog_destination destination, struct vlog_module *module, enum vlog_level level) { assert(destination >= 0 && destination < VLF_N_DESTINATIONS); assert(level < VLL_N_LEVELS); ovs_mutex_lock(&log_file_mutex); if (!module) { struct vlog_module *mp; LIST_FOR_EACH (mp, list, &vlog_modules) { mp->levels[destination] = level; update_min_level(mp); } } else { module->levels[destination] = level; update_min_level(module); } ovs_mutex_unlock(&log_file_mutex); } /* Sets the logging level for the given 'module' and 'destination' to 'level'. * A null 'module' or a 'destination' of VLF_ANY_DESTINATION is treated as a * wildcard across all modules or destinations, respectively. */ void vlog_set_levels(struct vlog_module *module, enum vlog_destination destination, enum vlog_level level) { assert(destination < VLF_N_DESTINATIONS || destination == VLF_ANY_DESTINATION); if (destination == VLF_ANY_DESTINATION) { for (destination = 0; destination < VLF_N_DESTINATIONS; destination++) { set_destination_level(destination, module, level); } } else { set_destination_level(destination, module, level); } } static void do_set_pattern(enum vlog_destination destination, const char *pattern) { struct destination *f = &destinations[destination]; ovs_rwlock_wrlock(&pattern_rwlock); if (!f->default_pattern) { free(f->pattern); } else { f->default_pattern = false; } f->pattern = xstrdup(pattern); ovs_rwlock_unlock(&pattern_rwlock); } /* Sets the pattern for the given 'destination' to 'pattern'. */ void vlog_set_pattern(enum vlog_destination destination, const char *pattern) { assert(destination < VLF_N_DESTINATIONS || destination == VLF_ANY_DESTINATION); if (destination == VLF_ANY_DESTINATION) { for (destination = 0; destination < VLF_N_DESTINATIONS; destination++) { do_set_pattern(destination, pattern); } } else { do_set_pattern(destination, pattern); } } /* Returns a copy of the name of the log file used by VLF_FILE, or NULL if none * is configured. The caller must eventually free the returned string. */ char * vlog_get_log_file(void) { ovs_mutex_lock(&log_file_mutex); char *fn = nullable_xstrdup(log_file_name); ovs_mutex_unlock(&log_file_mutex); return fn; } /* Sets the name of the log file used by VLF_FILE to 'new_log_file_name', or * closes the current log file if 'new_log_file_name' is NULL. Takes ownership * of 'new_log_file_name'. Returns 0 if successful, otherwise a positive errno * value. */ static int vlog_set_log_file__(char *new_log_file_name) { struct vlog_module *mp; struct stat old_stat; struct stat new_stat; int new_log_fd; bool same_file; bool log_close; /* Open new log file. */ if (new_log_file_name) { new_log_fd = open(new_log_file_name, O_WRONLY | O_CREAT | O_APPEND, 0660); if (new_log_fd < 0) { VLOG_WARN("failed to open %s for logging: %s", new_log_file_name, ovs_strerror(errno)); free(new_log_file_name); return errno; } } else { new_log_fd = -1; } /* If the new log file is the same one we already have open, bail out. */ ovs_mutex_lock(&log_file_mutex); same_file = ((log_fd < 0 && new_log_fd < 0) || (log_fd >= 0 && new_log_fd >= 0 && !fstat(log_fd, &old_stat) && !fstat(new_log_fd, &new_stat) && old_stat.st_dev == new_stat.st_dev && old_stat.st_ino == new_stat.st_ino)); ovs_mutex_unlock(&log_file_mutex); if (same_file) { close(new_log_fd); free(new_log_file_name); return 0; } /* Log closing old log file (we can't log while holding log_file_mutex). */ ovs_mutex_lock(&log_file_mutex); log_close = log_fd >= 0; ovs_mutex_unlock(&log_file_mutex); if (log_close) { VLOG_INFO("closing log file"); } /* Close old log file, if any. */ ovs_mutex_lock(&log_file_mutex); if (log_fd >= 0) { close(log_fd); } async_append_destroy(log_writer); free(log_file_name); /* Install new log file. */ log_file_name = nullable_xstrdup(new_log_file_name); log_fd = new_log_fd; log_writer = log_async ? async_append_create(new_log_fd) : NULL; LIST_FOR_EACH (mp, list, &vlog_modules) { update_min_level(mp); } ovs_mutex_unlock(&log_file_mutex); /* Log opening new log file (we can't log while holding log_file_mutex). */ VLOG_INFO("opened log file %s", new_log_file_name); free(new_log_file_name); return 0; } /* Closes the log file, if any. * * If the real goal is open a new log file, use vlog_set_log_file() to directly * do that: there is no need to close the old file first. */ void vlog_close_log_file(void) { vlog_set_log_file__(NULL); } /* Sets the name of the log file used by VLF_FILE to 'file_name', or to the * default file name if 'file_name' is null. Returns 0 if successful, * otherwise a positive errno value. */ int vlog_set_log_file(const char *file_name) { return vlog_set_log_file__( file_name ? xstrdup(file_name) : xasprintf("%s/%s.log", ovs_logdir(), program_name)); } /* Closes and then attempts to re-open the current log file. (This is useful * just after log rotation, to ensure that the new log file starts being used.) * Returns 0 if successful, otherwise a positive errno value. */ int vlog_reopen_log_file(void) { char *fn; ovs_mutex_lock(&log_file_mutex); fn = nullable_xstrdup(log_file_name); ovs_mutex_unlock(&log_file_mutex); if (fn) { int error = vlog_set_log_file(fn); free(fn); return error; } else { return 0; } } #ifndef _WIN32 /* In case a log file exists, change its owner to new 'user' and 'group'. * * This is useful for handling cases where the --log-file option is * specified ahead of the --user option. */ void vlog_change_owner_unix(uid_t user, gid_t group) { struct ds err = DS_EMPTY_INITIALIZER; int error; ovs_mutex_lock(&log_file_mutex); error = log_file_name ? chown(log_file_name, user, group) : 0; if (error) { /* Build the error message. We can not call VLOG_FATAL directly * here because VLOG_FATAL() will try again to to acquire * 'log_file_mutex' lock, causing deadlock. */ ds_put_format(&err, "Failed to change %s ownership: %s.", log_file_name, ovs_strerror(errno)); } ovs_mutex_unlock(&log_file_mutex); if (error) { VLOG_FATAL("%s", ds_steal_cstr(&err)); } } #endif /* Set debugging levels. Returns null if successful, otherwise an error * message that the caller must free(). */ char * vlog_set_levels_from_string(const char *s_) { char *s = xstrdup(s_); char *save_ptr = NULL; char *msg = NULL; char *word; word = strtok_r(s, " ,:\t", &save_ptr); if (word && !strcasecmp(word, "PATTERN")) { enum vlog_destination destination; word = strtok_r(NULL, " ,:\t", &save_ptr); if (!word) { msg = xstrdup("missing destination"); goto exit; } destination = (!strcasecmp(word, "ANY") ? VLF_ANY_DESTINATION : vlog_get_destination_val(word)); if (destination == VLF_N_DESTINATIONS) { msg = xasprintf("unknown destination \"%s\"", word); goto exit; } vlog_set_pattern(destination, save_ptr); } else if (word && !strcasecmp(word, "FACILITY")) { int value; if (!vlog_facility_exists(save_ptr, &value)) { msg = xstrdup("invalid facility"); goto exit; } atomic_store_explicit(&log_facility, value, memory_order_relaxed); } else { struct vlog_module *module = NULL; enum vlog_level level = VLL_N_LEVELS; enum vlog_destination destination = VLF_N_DESTINATIONS; for (; word != NULL; word = strtok_r(NULL, " ,:\t", &save_ptr)) { if (!strcasecmp(word, "ANY")) { continue; } else if (vlog_get_destination_val(word) != VLF_N_DESTINATIONS) { if (destination != VLF_N_DESTINATIONS) { msg = xstrdup("cannot specify multiple destinations"); goto exit; } destination = vlog_get_destination_val(word); } else if (vlog_get_level_val(word) != VLL_N_LEVELS) { if (level != VLL_N_LEVELS) { msg = xstrdup("cannot specify multiple levels"); goto exit; } level = vlog_get_level_val(word); } else if (vlog_module_from_name(word)) { if (module) { msg = xstrdup("cannot specify multiple modules"); goto exit; } module = vlog_module_from_name(word); } else { msg = xasprintf("no destination, level, or module \"%s\"", word); goto exit; } } if (destination == VLF_N_DESTINATIONS) { destination = VLF_ANY_DESTINATION; } if (level == VLL_N_LEVELS) { level = VLL_DBG; } vlog_set_levels(module, destination, level); } exit: free(s); return msg; } /* Set debugging levels. Abort with an error message if 's' is invalid. */ void vlog_set_levels_from_string_assert(const char *s) { char *error = vlog_set_levels_from_string(s); if (error) { ovs_fatal(0, "%s", error); } } /* If 'arg' is null, configure maximum verbosity. Otherwise, sets * configuration according to 'arg' (see vlog_set_levels_from_string()). */ void vlog_set_verbosity(const char *arg) { if (arg) { char *msg = vlog_set_levels_from_string(arg); if (msg) { ovs_fatal(0, "processing \"%s\": %s", arg, msg); } } else { vlog_set_levels(NULL, VLF_ANY_DESTINATION, VLL_DBG); } } void vlog_set_syslog_method(const char *method) { if (syslogger) { /* Set syslogger only, if one is not already set. This effectively * means that only the first --syslog-method argument is honored. */ return; } if (!strcmp(method, "null")) { syslogger = syslog_null_create(); } else if (!strcmp(method, "libc")) { syslogger = syslog_libc_create(); } else if (!strncmp(method, "udp:", 4) || !strncmp(method, "unix:", 5)) { syslogger = syslog_direct_create(method); } else { ovs_fatal(0, "unsupported syslog method '%s'", method); } } /* Set the vlog udp syslog target. */ void vlog_set_syslog_target(const char *target) { int new_fd; inet_open_active(SOCK_DGRAM, target, -1, NULL, &new_fd, 0); ovs_rwlock_wrlock(&pattern_rwlock); if (syslog_fd >= 0) { close(syslog_fd); } syslog_fd = new_fd; ovs_rwlock_unlock(&pattern_rwlock); } /* * This function writes directly to log file without using async writer or * taking a lock. Caller must hold 'log_file_mutex' or be sure that it's * not necessary. Could be used in exceptional cases like dumping of backtrace * on fatal signals. */ void vlog_direct_write_to_log_file_unsafe(const char *s) OVS_NO_THREAD_SAFETY_ANALYSIS { if (log_fd >= 0) { ignore(write(log_fd, s, strlen(s))); } } /* Returns 'false' if 'facility' is not a valid string. If 'facility' * is a valid string, sets 'value' with the integer value of 'facility' * and returns 'true'. */ static bool vlog_facility_exists(const char* facility, int *value) { size_t i; for (i = 0; i < ARRAY_SIZE(vlog_facilities); i++) { if (!strcasecmp(vlog_facilities[i].name, facility)) { *value = vlog_facilities[i].value; return true; } } return false; } static void vlog_unixctl_set(struct unixctl_conn *conn, int argc, const char *argv[], void *aux OVS_UNUSED) { int i; /* With no argument, set all destinations and modules to "dbg". */ if (argc == 1) { vlog_set_levels(NULL, VLF_ANY_DESTINATION, VLL_DBG); } for (i = 1; i < argc; i++) { char *msg = vlog_set_levels_from_string(argv[i]); if (msg) { unixctl_command_reply_error(conn, msg); free(msg); return; } } unixctl_command_reply(conn, NULL); } static void vlog_unixctl_list(struct unixctl_conn *conn, int argc OVS_UNUSED, const char *argv[] OVS_UNUSED, void *aux OVS_UNUSED) { char *msg = vlog_get_levels(); unixctl_command_reply(conn, msg); free(msg); } static void vlog_unixctl_list_pattern(struct unixctl_conn *conn, int argc OVS_UNUSED, const char *argv[] OVS_UNUSED, void *aux OVS_UNUSED) { char *msg; msg = vlog_get_patterns(); unixctl_command_reply(conn, msg); free(msg); } static void vlog_unixctl_reopen(struct unixctl_conn *conn, int argc OVS_UNUSED, const char *argv[] OVS_UNUSED, void *aux OVS_UNUSED) { bool has_log_file; ovs_mutex_lock(&log_file_mutex); has_log_file = log_file_name != NULL; ovs_mutex_unlock(&log_file_mutex); if (has_log_file) { int error = vlog_reopen_log_file(); if (error) { unixctl_command_reply_error(conn, ovs_strerror(errno)); } else { unixctl_command_reply(conn, NULL); } } else { unixctl_command_reply_error(conn, "Logging to file not configured"); } } static void vlog_unixctl_close(struct unixctl_conn *conn, int argc OVS_UNUSED, const char *argv[] OVS_UNUSED, void *aux OVS_UNUSED) { ovs_mutex_lock(&log_file_mutex); if (log_fd >= 0) { close(log_fd); log_fd = -1; async_append_destroy(log_writer); log_writer = NULL; struct vlog_module *mp; LIST_FOR_EACH (mp, list, &vlog_modules) { update_min_level(mp); } } ovs_mutex_unlock(&log_file_mutex); unixctl_command_reply(conn, NULL); } static void set_all_rate_limits(bool enable) { struct vlog_module *mp; ovs_mutex_lock(&log_file_mutex); LIST_FOR_EACH (mp, list, &vlog_modules) { mp->honor_rate_limits = enable; } ovs_mutex_unlock(&log_file_mutex); } static void set_rate_limits(struct unixctl_conn *conn, int argc, const char *argv[], bool enable) { if (argc > 1) { int i; for (i = 1; i < argc; i++) { if (!strcasecmp(argv[i], "ANY")) { set_all_rate_limits(enable); } else { struct vlog_module *module = vlog_module_from_name(argv[i]); if (!module) { unixctl_command_reply_error(conn, "unknown module"); return; } module->honor_rate_limits = enable; } } } else { set_all_rate_limits(enable); } unixctl_command_reply(conn, NULL); } static void vlog_enable_rate_limit(struct unixctl_conn *conn, int argc, const char *argv[], void *aux OVS_UNUSED) { set_rate_limits(conn, argc, argv, true); } static void vlog_disable_rate_limit(struct unixctl_conn *conn, int argc, const char *argv[], void *aux OVS_UNUSED) { set_rate_limits(conn, argc, argv, false); } /* Initializes the logging subsystem and registers its unixctl server * commands. */ void vlog_init(void) { static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER; if (ovsthread_once_start(&once)) { long long int now; int facility; bool print_syslog_target_deprecation; /* Do initialization work that needs to be done before any logging * occurs. We want to keep this really minimal because any attempt to * log anything before calling ovsthread_once_done() will deadlock. */ atomic_read_explicit(&log_facility, &facility, memory_order_relaxed); if (!syslogger) { char *env = getenv("OVS_SYSLOG_METHOD"); if (env && env[0]) { vlog_set_syslog_method(env); } else { syslogger = syslog_libc_create(); } } syslogger->class->openlog(syslogger, facility ? facility : LOG_DAEMON); ovsthread_once_done(&once); /* Now do anything that we want to happen only once but doesn't have to * finish before we start logging. */ now = time_wall_msec(); if (now < 0) { char *s = xastrftime_msec("%a, %d %b %Y %H:%M:%S", now, true); VLOG_ERR("current time is negative: %s (%lld)", s, now); free(s); } unixctl_command_register( "vlog/set", "{spec | PATTERN:destination:pattern}", 0, INT_MAX, vlog_unixctl_set, NULL); unixctl_command_register("vlog/list", "", 0, 0, vlog_unixctl_list, NULL); unixctl_command_register("vlog/list-pattern", "", 0, 0, vlog_unixctl_list_pattern, NULL); unixctl_command_register("vlog/enable-rate-limit", "[module]...", 0, INT_MAX, vlog_enable_rate_limit, NULL); unixctl_command_register("vlog/disable-rate-limit", "[module]...", 0, INT_MAX, vlog_disable_rate_limit, NULL); unixctl_command_register("vlog/reopen", "", 0, 0, vlog_unixctl_reopen, NULL); unixctl_command_register("vlog/close", "", 0, 0, vlog_unixctl_close, NULL); ovs_rwlock_rdlock(&pattern_rwlock); print_syslog_target_deprecation = syslog_fd >= 0; ovs_rwlock_unlock(&pattern_rwlock); if (print_syslog_target_deprecation) { VLOG_WARN("--syslog-target flag is deprecated, use " "--syslog-method instead"); } } } /* Enables VLF_FILE log output to be written asynchronously to disk. * Asynchronous file writes avoid blocking the process in the case of a busy * disk, but on the other hand they are less robust: there is a chance that the * write will not make it to the log file if the process crashes soon after the * log call. */ void vlog_enable_async(void) { ovs_mutex_lock(&log_file_mutex); log_async = true; if (log_fd >= 0 && !log_writer) { log_writer = async_append_create(log_fd); } ovs_mutex_unlock(&log_file_mutex); } void vlog_disable_async(void) { ovs_mutex_lock(&log_file_mutex); log_async = false; async_append_destroy(log_writer); log_writer = NULL; ovs_mutex_unlock(&log_file_mutex); } /* Print the current logging level for each module. */ char * vlog_get_levels(void) { struct ds s = DS_EMPTY_INITIALIZER; struct vlog_module *mp; struct svec lines = SVEC_EMPTY_INITIALIZER; size_t i; ds_put_format(&s, " console syslog file\n"); ds_put_format(&s, " ------- ------ ------\n"); ovs_mutex_lock(&log_file_mutex); LIST_FOR_EACH (mp, list, &vlog_modules) { struct ds line; ds_init(&line); ds_put_format(&line, "%-16s %4s %4s %4s", vlog_get_module_name(mp), vlog_get_level_name(vlog_get_level(mp, VLF_CONSOLE)), vlog_get_level_name(vlog_get_level(mp, VLF_SYSLOG)), vlog_get_level_name(vlog_get_level(mp, VLF_FILE))); if (!mp->honor_rate_limits) { ds_put_cstr(&line, " (rate limiting disabled)"); } ds_put_char(&line, '\n'); svec_add_nocopy(&lines, ds_steal_cstr(&line)); } ovs_mutex_unlock(&log_file_mutex); svec_sort(&lines); char *line; SVEC_FOR_EACH (i, line, &lines) { ds_put_cstr(&s, line); } svec_destroy(&lines); return ds_cstr(&s); } /* Returns as a string current logging patterns for each destination. * This string must be released by caller. */ char * vlog_get_patterns(void) { struct ds ds = DS_EMPTY_INITIALIZER; enum vlog_destination destination; ovs_rwlock_rdlock(&pattern_rwlock); ds_put_format(&ds, " prefix format\n"); ds_put_format(&ds, " ------ ------\n"); for (destination = 0; destination < VLF_N_DESTINATIONS; destination++) { struct destination *f = &destinations[destination]; const char *prefix = "none"; if (destination == VLF_SYSLOG && syslogger) { prefix = syslog_get_prefix(syslogger); } ds_put_format(&ds, "%-7s %-32s %s\n", f->name, prefix, f->pattern); } ovs_rwlock_unlock(&pattern_rwlock); return ds_cstr(&ds); } /* Returns true if a log message emitted for the given 'module' and 'level' * would cause some log output, false if that module and level are completely * disabled. */ bool vlog_is_enabled(const struct vlog_module *module, enum vlog_level level) { return module->min_level >= level; } static const char * fetch_braces(const char *p, const char *def, char *out, size_t out_size) { if (*p == '{') { size_t n = strcspn(p + 1, "}"); size_t n_copy = MIN(n, out_size - 1); memcpy(out, p + 1, n_copy); out[n_copy] = '\0'; p += n + 2; } else { ovs_strlcpy(out, def, out_size); } return p; } static void format_log_message(const struct vlog_module *module, enum vlog_level level, const char *pattern, const char *message, va_list args_, struct ds *s) { char tmp[128]; va_list args; const char *p; int facility; ds_clear(s); for (p = pattern; *p != '\0'; ) { const char *subprogram_name; enum { LEFT, RIGHT } justify = RIGHT; int pad = ' '; size_t length, field, used; if (*p != '%') { ds_put_char(s, *p++); continue; } p++; if (*p == '-') { justify = LEFT; p++; } if (*p == '0') { pad = '0'; p++; } field = 0; while (isdigit((unsigned char)*p)) { field = (field * 10) + (*p - '0'); p++; } length = s->length; switch (*p++) { case 'A': ds_put_cstr(s, program_name); break; case 'B': atomic_read_explicit(&log_facility, &facility, memory_order_relaxed); facility = facility ? facility : LOG_LOCAL0; ds_put_format(s, "%d", facility + syslog_levels[level]); break; case 'c': p = fetch_braces(p, "", tmp, sizeof tmp); ds_put_cstr(s, vlog_get_module_name(module)); break; case 'd': p = fetch_braces(p, "%Y-%m-%d %H:%M:%S.###", tmp, sizeof tmp); ds_put_strftime_msec(s, tmp, time_wall_msec(), false); break; case 'D': p = fetch_braces(p, "%Y-%m-%d %H:%M:%S.###", tmp, sizeof tmp); ds_put_strftime_msec(s, tmp, time_wall_msec(), true); break; case 'E': gethostname(tmp, sizeof tmp); tmp[sizeof tmp - 1] = '\0'; ds_put_cstr(s, tmp); break; case 'm': /* Format user-supplied log message and trim trailing new-lines. */ length = s->length; va_copy(args, args_); ds_put_format_valist(s, message, args); va_end(args); while (s->length > length && s->string[s->length - 1] == '\n') { s->length--; } break; case 'N': ds_put_format(s, "%u", *msg_num_get_unsafe()); break; case 'n': ds_put_char(s, '\n'); break; case 'p': ds_put_cstr(s, vlog_get_level_name(level)); break; case 'P': ds_put_format(s, "%ld", (long int) getpid()); break; case 'r': ds_put_format(s, "%lld", time_msec() - time_boot_msec()); break; case 't': subprogram_name = get_subprogram_name(); ds_put_cstr(s, subprogram_name[0] ? subprogram_name : "main"); break; case 'T': subprogram_name = get_subprogram_name(); if (subprogram_name[0]) { ds_put_format(s, "(%s)", subprogram_name); } break; default: ds_put_char(s, p[-1]); break; } used = s->length - length; if (used < field) { size_t n_pad = field - used; if (justify == RIGHT) { ds_put_uninit(s, n_pad); memmove(&s->string[length + n_pad], &s->string[length], used); memset(&s->string[length], pad, n_pad); } else { ds_put_char_multiple(s, pad, n_pad); } } } } /* Exports the given 'syslog_message' to the configured udp syslog sink. */ static void send_to_syslog_fd(const char *s, size_t length) OVS_REQ_RDLOCK(pattern_rwlock) { static size_t max_length = SIZE_MAX; size_t send_len = MIN(length, max_length); while (write(syslog_fd, s, send_len) < 0 && errno == EMSGSIZE) { send_len -= send_len / 20; max_length = send_len; } } /* Writes 'message' to the log at the given 'level' and as coming from the * given 'module'. * * Guaranteed to preserve errno. */ void vlog_valist(const struct vlog_module *module, enum vlog_level level, const char *message, va_list args) { bool log_to_console = module->levels[VLF_CONSOLE] >= level; bool log_to_syslog = module->levels[VLF_SYSLOG] >= level; bool log_to_file = module->levels[VLF_FILE] >= level; if (!(log_to_console || log_to_syslog || log_to_file)) { /* fast path - all logging levels specify no logging, no * need to hog the log mutex */ return; } ovs_mutex_lock(&log_file_mutex); log_to_file &= (log_fd >= 0); ovs_mutex_unlock(&log_file_mutex); if (log_to_console || log_to_syslog || log_to_file) { int save_errno = errno; struct ds s; vlog_init(); ds_init(&s); ds_reserve(&s, 1024); ++*msg_num_get(); ovs_rwlock_rdlock(&pattern_rwlock); if (log_to_console) { format_log_message(module, level, destinations[VLF_CONSOLE].pattern, message, args, &s); ds_put_char(&s, '\n'); fputs(ds_cstr(&s), stderr); } if (log_to_syslog) { int syslog_level = syslog_levels[level]; char *save_ptr = NULL; char *line; int facility; format_log_message(module, level, destinations[VLF_SYSLOG].pattern, message, args, &s); for (line = strtok_r(s.string, "\n", &save_ptr); line; line = strtok_r(NULL, "\n", &save_ptr)) { atomic_read_explicit(&log_facility, &facility, memory_order_relaxed); syslogger->class->syslog(syslogger, syslog_level|facility, line); } if (syslog_fd >= 0) { format_log_message(module, level, "<%B>1 %D{%Y-%m-%dT%H:%M:%S.###Z} " "%E %A %P %c - \xef\xbb\xbf%m", message, args, &s); send_to_syslog_fd(ds_cstr(&s), s.length); } } if (log_to_file) { format_log_message(module, level, destinations[VLF_FILE].pattern, message, args, &s); ds_put_char(&s, '\n'); ovs_mutex_lock(&log_file_mutex); if (log_fd >= 0) { if (log_writer) { async_append_write(log_writer, s.string, s.length); if (level == VLL_EMER) { async_append_flush(log_writer); } } else { ignore(write(log_fd, s.string, s.length)); } } ovs_mutex_unlock(&log_file_mutex); } ovs_rwlock_unlock(&pattern_rwlock); ds_destroy(&s); errno = save_errno; } } void vlog(const struct vlog_module *module, enum vlog_level level, const char *message, ...) { va_list args; va_start(args, message); vlog_valist(module, level, message, args); va_end(args); } /* Logs 'message' to 'module' at maximum verbosity, then exits with a failure * exit code. Always writes the message to stderr, even if the console * destination is disabled. * * Choose this function instead of vlog_abort_valist() if the daemon monitoring * facility shouldn't automatically restart the current daemon. */ void vlog_fatal_valist(const struct vlog_module *module_, const char *message, va_list args) { struct vlog_module *module = CONST_CAST(struct vlog_module *, module_); /* Don't log this message to the console to avoid redundancy with the * message written by the later ovs_fatal_valist(). */ module->levels[VLF_CONSOLE] = VLL_OFF; vlog_valist(module, VLL_EMER, message, args); ovs_fatal_valist(0, message, args); } /* Logs 'message' to 'module' at maximum verbosity, then exits with a failure * exit code. Always writes the message to stderr, even if the console * destination is disabled. * * Choose this function instead of vlog_abort() if the daemon monitoring * facility shouldn't automatically restart the current daemon. */ void vlog_fatal(const struct vlog_module *module, const char *message, ...) { va_list args; va_start(args, message); vlog_fatal_valist(module, message, args); va_end(args); } /* Logs 'message' to 'module' at maximum verbosity, then calls abort(). Always * writes the message to stderr, even if the console destination is disabled. * * Choose this function instead of vlog_fatal_valist() if the daemon monitoring * facility should automatically restart the current daemon. */ void vlog_abort_valist(const struct vlog_module *module_, const char *message, va_list args) { struct vlog_module *module = (struct vlog_module *) module_; /* Don't log this message to the console to avoid redundancy with the * message written by the later ovs_abort_valist(). */ module->levels[VLF_CONSOLE] = VLL_OFF; vlog_valist(module, VLL_EMER, message, args); ovs_abort_valist(0, message, args); } /* Logs 'message' to 'module' at maximum verbosity, then calls abort(). Always * writes the message to stderr, even if the console destination is disabled. * * Choose this function instead of vlog_fatal() if the daemon monitoring * facility should automatically restart the current daemon. */ void vlog_abort(const struct vlog_module *module, const char *message, ...) { va_list args; va_start(args, message); vlog_abort_valist(module, message, args); va_end(args); } bool vlog_should_drop(const struct vlog_module *module, enum vlog_level level, struct vlog_rate_limit *rl) { if (!module->honor_rate_limits) { return false; } if (!vlog_is_enabled(module, level)) { return true; } ovs_mutex_lock(&rl->mutex); if (!token_bucket_withdraw(&rl->token_bucket, VLOG_MSG_TOKENS)) { time_t now = time_now(); if (!rl->n_dropped) { rl->first_dropped = now; } rl->last_dropped = now; rl->n_dropped++; ovs_mutex_unlock(&rl->mutex); return true; } if (!rl->n_dropped) { ovs_mutex_unlock(&rl->mutex); } else { time_t now = time_now(); unsigned int n_dropped = rl->n_dropped; unsigned int first_dropped_elapsed = now - rl->first_dropped; unsigned int last_dropped_elapsed = now - rl->last_dropped; rl->n_dropped = 0; ovs_mutex_unlock(&rl->mutex); vlog(module, level, "Dropped %u log messages in last %u seconds (most recently, " "%u seconds ago) due to excessive rate", n_dropped, first_dropped_elapsed, last_dropped_elapsed); } return false; } void vlog_rate_limit(const struct vlog_module *module, enum vlog_level level, struct vlog_rate_limit *rl, const char *message, ...) { if (!vlog_should_drop(module, level, rl)) { va_list args; va_start(args, message); vlog_valist(module, level, message, args); va_end(args); } } void vlog_usage(void) { printf("\n\ Logging options:\n\ -vSPEC, --verbose=SPEC set logging levels\n\ -v, --verbose set maximum verbosity level\n\ --log-file[=FILE] enable logging to specified FILE\n\ (default: %s/%s.log)\n\ --syslog-method=(libc|unix:file|udp:ip:port)\n\ specify how to send messages to syslog daemon\n\ --syslog-target=HOST:PORT also send syslog msgs to HOST:PORT via UDP\n", ovs_logdir(), program_name); }