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Diffstat (limited to 'include/openvswitch/vlog.h')
| -rw-r--r-- | include/openvswitch/vlog.h | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/include/openvswitch/vlog.h b/include/openvswitch/vlog.h new file mode 100644 index 000000000..3f71e4bd7 --- /dev/null +++ b/include/openvswitch/vlog.h @@ -0,0 +1,296 @@ +/* + * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 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. + */ + +#ifndef OPENVSWITCH_VLOG_H +#define OPENVSWITCH_VLOG_H 1 + +/* Logging. + * + * + * Thread-safety + * ============= + * + * Fully thread safe. + */ + +#include <limits.h> +#include <stdarg.h> +#include <stdbool.h> +#include <time.h> +#include <openvswitch/compiler.h> +#include <openvswitch/list.h> +#include <openvswitch/thread.h> +#include <openvswitch/token-bucket.h> +#include <openvswitch/util.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/* Logging severity levels. + * + * ovs-appctl(8) defines each of the log levels. */ +#define VLOG_LEVELS \ + VLOG_LEVEL(OFF, LOG_ALERT, 1) \ + VLOG_LEVEL(EMER, LOG_ALERT, 1) \ + VLOG_LEVEL(ERR, LOG_ERR, 3) \ + VLOG_LEVEL(WARN, LOG_WARNING, 4) \ + VLOG_LEVEL(INFO, LOG_NOTICE, 5) \ + VLOG_LEVEL(DBG, LOG_DEBUG, 7) +enum vlog_level { +#define VLOG_LEVEL(NAME, SYSLOG_LEVEL, RFC5424_LEVEL) VLL_##NAME, + VLOG_LEVELS +#undef VLOG_LEVEL + VLL_N_LEVELS +}; + +const char *vlog_get_level_name(enum vlog_level); +enum vlog_level vlog_get_level_val(const char *name); + +/* Facilities that we can log to. */ +#define VLOG_FACILITIES \ + VLOG_FACILITY(SYSLOG, "ovs|%05N|%c%T|%p|%m") \ + VLOG_FACILITY(CONSOLE, "%D{%Y-%m-%dT%H:%M:%SZ}|%05N|%c%T|%p|%m") \ + VLOG_FACILITY(FILE, "%D{%Y-%m-%dT%H:%M:%S.###Z}|%05N|%c%T|%p|%m") +enum vlog_facility { +#define VLOG_FACILITY(NAME, PATTERN) VLF_##NAME, + VLOG_FACILITIES +#undef VLOG_FACILITY + VLF_N_FACILITIES, + VLF_ANY_FACILITY = -1 +}; + +const char *vlog_get_facility_name(enum vlog_facility); +enum vlog_facility vlog_get_facility_val(const char *name); + +/* A log module. */ +struct vlog_module { + struct ovs_list list; + const char *name; /* User-visible name. */ + int levels[VLF_N_FACILITIES]; /* Minimum log level for each facility. */ + int min_level; /* Minimum log level for any facility. */ + bool honor_rate_limits; /* Set false to ignore rate limits. */ +}; + +/* Global list of all logging modules */ +extern struct ovs_list vlog_modules; + +void vlog_insert_module(struct ovs_list *); + +/* Creates and initializes a global instance of a module named MODULE. */ +#define VLOG_DEFINE_MODULE(MODULE) \ + VLOG_DEFINE_MODULE__(MODULE) \ + OVS_CONSTRUCTOR(init_##MODULE) { \ + vlog_insert_module(&VLM_##MODULE.list); \ + } \ + +const char *vlog_get_module_name(const struct vlog_module *); +struct vlog_module *vlog_module_from_name(const char *name); + +/* Rate-limiter for log messages. */ +struct vlog_rate_limit { + struct token_bucket token_bucket; + time_t first_dropped; /* Time first message was dropped. */ + time_t last_dropped; /* Time of most recent message drop. */ + unsigned int n_dropped; /* Number of messages dropped. */ + struct ovs_mutex mutex; /* Mutual exclusion for rate limit. */ +}; + +/* Number of tokens to emit a message. We add 'rate' tokens per millisecond, + * thus 60,000 tokens are required to emit one message per minute. */ +#define VLOG_MSG_TOKENS (60 * 1000) + +/* Initializer for a struct vlog_rate_limit, to set up a maximum rate of RATE + * messages per minute and a maximum burst size of BURST messages. */ +#define VLOG_RATE_LIMIT_INIT(RATE, BURST) \ + { \ + TOKEN_BUCKET_INIT(RATE, OVS_SAT_MUL(BURST, VLOG_MSG_TOKENS)), \ + 0, /* first_dropped */ \ + 0, /* last_dropped */ \ + 0, /* n_dropped */ \ + OVS_MUTEX_INITIALIZER /* mutex */ \ + } + +/* Configuring how each module logs messages. */ +enum vlog_level vlog_get_level(const struct vlog_module *, enum vlog_facility); +void vlog_set_levels(struct vlog_module *, + enum vlog_facility, enum vlog_level); +char *vlog_set_levels_from_string(const char *) OVS_WARN_UNUSED_RESULT; +void vlog_set_levels_from_string_assert(const char *); +char *vlog_get_levels(void); +bool vlog_is_enabled(const struct vlog_module *, enum vlog_level); +bool vlog_should_drop(const struct vlog_module *, enum vlog_level, + struct vlog_rate_limit *); +void vlog_set_verbosity(const char *arg); + +/* Configuring log facilities. */ +void vlog_set_pattern(enum vlog_facility, const char *pattern); +int vlog_set_log_file(const char *file_name); +int vlog_reopen_log_file(void); + +/* Configure syslog target. */ +void vlog_set_syslog_target(const char *target); + +/* Initialization. */ +void vlog_init(void); +void vlog_enable_async(void); + +/* Functions for actual logging. */ +void vlog(const struct vlog_module *, enum vlog_level, const char *format, ...) + OVS_PRINTF_FORMAT (3, 4); +void vlog_valist(const struct vlog_module *, enum vlog_level, + const char *, va_list) + OVS_PRINTF_FORMAT (3, 0); + +OVS_NO_RETURN void vlog_fatal(const struct vlog_module *, const char *format, ...) + OVS_PRINTF_FORMAT (2, 3); +OVS_NO_RETURN void vlog_fatal_valist(const struct vlog_module *, + const char *format, va_list) + OVS_PRINTF_FORMAT (2, 0); + +OVS_NO_RETURN void vlog_abort(const struct vlog_module *, const char *format, ...) + OVS_PRINTF_FORMAT (2, 3); +OVS_NO_RETURN void vlog_abort_valist(const struct vlog_module *, + const char *format, va_list) + OVS_PRINTF_FORMAT (2, 0); + +void vlog_rate_limit(const struct vlog_module *, enum vlog_level, + struct vlog_rate_limit *, const char *, ...) + OVS_PRINTF_FORMAT (4, 5); + +/* Creates and initializes a global instance of a module named MODULE, and + * defines a static variable named THIS_MODULE that points to it, for use with + * the convenience macros below. */ +#define VLOG_DEFINE_THIS_MODULE(MODULE) \ + VLOG_DEFINE_MODULE(MODULE); \ + static struct vlog_module *const THIS_MODULE = &VLM_##MODULE + +/* Convenience macros. These assume that THIS_MODULE points to a "struct + * vlog_module" for the current module, as set up by e.g. the + * VLOG_DEFINE_MODULE macro above. + * + * Guaranteed to preserve errno. + */ +#define VLOG_FATAL(...) vlog_fatal(THIS_MODULE, __VA_ARGS__) +#define VLOG_ABORT(...) vlog_abort(THIS_MODULE, __VA_ARGS__) +#define VLOG_EMER(...) VLOG(VLL_EMER, __VA_ARGS__) +#define VLOG_ERR(...) VLOG(VLL_ERR, __VA_ARGS__) +#define VLOG_WARN(...) VLOG(VLL_WARN, __VA_ARGS__) +#define VLOG_INFO(...) VLOG(VLL_INFO, __VA_ARGS__) +#define VLOG_DBG(...) VLOG(VLL_DBG, __VA_ARGS__) + +/* More convenience macros, for testing whether a given level is enabled in + * THIS_MODULE. When constructing a log message is expensive, this enables it + * to be skipped. */ +#define VLOG_IS_ERR_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_ERR) +#define VLOG_IS_WARN_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_WARN) +#define VLOG_IS_INFO_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_INFO) +#define VLOG_IS_DBG_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_DBG) + +/* Convenience macros for rate-limiting. + * Guaranteed to preserve errno. + */ +#define VLOG_ERR_RL(RL, ...) VLOG_RL(RL, VLL_ERR, __VA_ARGS__) +#define VLOG_WARN_RL(RL, ...) VLOG_RL(RL, VLL_WARN, __VA_ARGS__) +#define VLOG_INFO_RL(RL, ...) VLOG_RL(RL, VLL_INFO, __VA_ARGS__) +#define VLOG_DBG_RL(RL, ...) VLOG_RL(RL, VLL_DBG, __VA_ARGS__) + +/* Convenience macros to additionally store log message in buffer + * Caller is responsible for freeing *ERRP afterwards */ +#define VLOG_ERR_BUF(ERRP, ...) VLOG_ERRP(ERRP, VLL_ERR, __VA_ARGS__) +#define VLOG_WARN_BUF(ERRP, ...) VLOG_ERRP(ERRP, VLL_WARN, __VA_ARGS__) + +#define VLOG_DROP_ERR(RL) vlog_should_drop(THIS_MODULE, VLL_ERR, RL) +#define VLOG_DROP_WARN(RL) vlog_should_drop(THIS_MODULE, VLL_WARN, RL) +#define VLOG_DROP_INFO(RL) vlog_should_drop(THIS_MODULE, VLL_INFO, RL) +#define VLOG_DROP_DBG(RL) vlog_should_drop(THIS_MODULE, VLL_DBG, RL) + +/* Macros for logging at most once per execution. */ +#define VLOG_ERR_ONCE(...) VLOG_ONCE(VLL_ERR, __VA_ARGS__) +#define VLOG_WARN_ONCE(...) VLOG_ONCE(VLL_WARN, __VA_ARGS__) +#define VLOG_INFO_ONCE(...) VLOG_ONCE(VLL_INFO, __VA_ARGS__) +#define VLOG_DBG_ONCE(...) VLOG_ONCE(VLL_DBG, __VA_ARGS__) + +/* Command line processing. */ +#define VLOG_OPTION_ENUMS \ + OPT_LOG_FILE, \ + OPT_SYSLOG_TARGET + +#define VLOG_LONG_OPTIONS \ + {"verbose", optional_argument, NULL, 'v'}, \ + {"log-file", optional_argument, NULL, OPT_LOG_FILE}, \ + {"syslog-target", optional_argument, NULL, OPT_SYSLOG_TARGET} + +#define VLOG_OPTION_HANDLERS \ + case 'v': \ + vlog_set_verbosity(optarg); \ + break; \ + case OPT_LOG_FILE: \ + vlog_set_log_file(optarg); \ + break; \ + case OPT_SYSLOG_TARGET: \ + vlog_set_syslog_target(optarg); \ + break; + +void vlog_usage(void); + +/* Implementation details. */ +#define VLOG(LEVEL, ...) \ + do { \ + enum vlog_level level__ = LEVEL; \ + if (THIS_MODULE->min_level >= level__) { \ + vlog(THIS_MODULE, level__, __VA_ARGS__); \ + } \ + } while (0) +#define VLOG_RL(RL, LEVEL, ...) \ + do { \ + enum vlog_level level__ = LEVEL; \ + if (THIS_MODULE->min_level >= level__) { \ + vlog_rate_limit(THIS_MODULE, level__, RL, __VA_ARGS__); \ + } \ + } while (0) +#define VLOG_ONCE(LEVEL, ...) \ + do { \ + static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER; \ + if (ovsthread_once_start(&once)) { \ + vlog(THIS_MODULE, LEVEL, __VA_ARGS__); \ + ovsthread_once_done(&once); \ + } \ + } while (0) +#define VLOG_ERRP(ERRP, LEVEL, ...) \ + do { \ + VLOG(LEVEL, __VA_ARGS__); \ + if (ERRP) { \ + *(ERRP) = xasprintf(__VA_ARGS__); \ + } \ + } while (0) + +#define VLOG_DEFINE_MODULE__(MODULE) \ + extern struct vlog_module VLM_##MODULE; \ + struct vlog_module VLM_##MODULE = \ + { \ + OVS_LIST_INITIALIZER(&VLM_##MODULE.list), \ + #MODULE, /* name */ \ + { VLL_INFO, VLL_INFO, VLL_INFO }, /* levels */ \ + VLL_INFO, /* min_level */ \ + true /* honor_rate_limits */ \ + }; + +#ifdef __cplusplus +} +#endif + +#endif /* vlog.h */ |