*
* Linux Trace Toolkit Control Library Header File
*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- *
- * This library is free software; you can redistribute it and/or modify it
- * under the terms of the GNU Lesser General Public License, version 2.1 only,
- * as published by the Free Software Foundation.
- *
- * This library 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 Lesser General Public License
- * for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with this library; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef _LTTNG_H
-#define _LTTNG_H
-
-#include <limits.h>
-#include <stdint.h>
-#include <sys/types.h>
-
-/*
- * Event symbol length. Copied from LTTng kernel ABI.
- */
-#define LTTNG_SYMBOL_NAME_LEN 256
-
-/*
- * Maximum length of a domain name. This is the limit for the total length of a
- * domain name specified by the RFC 1035 (https://www.ietf.org/rfc/rfc1035.txt)
- */
-#define LTTNG_MAX_DNNAME 255
-
-/*
- * Every lttng_event_* structure both apply to kernel event and user-space
- * event.
- */
-
-/*
- * Domain types: the different possible tracers.
- */
-enum lttng_domain_type {
- LTTNG_DOMAIN_KERNEL = 1,
- LTTNG_DOMAIN_UST = 2,
-
- /*
- * For now, the domains below are not implemented. However, we keep them
- * here in order to retain their enum values for future development. Note
- * that it is on the roadmap to implement them.
- *
- LTTNG_DOMAIN_UST_EXEC_NAME = 3,
- LTTNG_DOMAIN_UST_PID = 4,
- LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN = 5,
- */
-};
-
-/*
- * Instrumentation type of tracing event.
- */
-enum lttng_event_type {
- LTTNG_EVENT_ALL = -1,
- LTTNG_EVENT_TRACEPOINT = 0,
- LTTNG_EVENT_PROBE = 1,
- LTTNG_EVENT_FUNCTION = 2,
- LTTNG_EVENT_FUNCTION_ENTRY = 3,
- LTTNG_EVENT_NOOP = 4,
- LTTNG_EVENT_SYSCALL = 5,
-};
-
-/*
- * Loglevel information.
- */
-enum lttng_loglevel_type {
- LTTNG_EVENT_LOGLEVEL_ALL = 0,
- LTTNG_EVENT_LOGLEVEL_RANGE = 1,
- LTTNG_EVENT_LOGLEVEL_SINGLE = 2,
-};
-
-/*
- * Available loglevels.
- */
-enum lttng_loglevel {
- LTTNG_LOGLEVEL_EMERG = 0,
- LTTNG_LOGLEVEL_ALERT = 1,
- LTTNG_LOGLEVEL_CRIT = 2,
- LTTNG_LOGLEVEL_ERR = 3,
- LTTNG_LOGLEVEL_WARNING = 4,
- LTTNG_LOGLEVEL_NOTICE = 5,
- LTTNG_LOGLEVEL_INFO = 6,
- LTTNG_LOGLEVEL_DEBUG_SYSTEM = 7,
- LTTNG_LOGLEVEL_DEBUG_PROGRAM = 8,
- LTTNG_LOGLEVEL_DEBUG_PROCESS = 9,
- LTTNG_LOGLEVEL_DEBUG_MODULE = 10,
- LTTNG_LOGLEVEL_DEBUG_UNIT = 11,
- LTTNG_LOGLEVEL_DEBUG_FUNCTION = 12,
- LTTNG_LOGLEVEL_DEBUG_LINE = 13,
- LTTNG_LOGLEVEL_DEBUG = 14,
-};
-
-/*
- * LTTng consumer mode
- */
-enum lttng_event_output {
- LTTNG_EVENT_SPLICE = 0,
- LTTNG_EVENT_MMAP = 1,
-};
-
-/* Event context possible type */
-enum lttng_event_context_type {
- LTTNG_EVENT_CONTEXT_PID = 0,
- LTTNG_EVENT_CONTEXT_PERF_COUNTER = 1,
- LTTNG_EVENT_CONTEXT_PROCNAME = 2,
- LTTNG_EVENT_CONTEXT_PRIO = 3,
- LTTNG_EVENT_CONTEXT_NICE = 4,
- LTTNG_EVENT_CONTEXT_VPID = 5,
- LTTNG_EVENT_CONTEXT_TID = 6,
- LTTNG_EVENT_CONTEXT_VTID = 7,
- LTTNG_EVENT_CONTEXT_PPID = 8,
- LTTNG_EVENT_CONTEXT_VPPID = 9,
- LTTNG_EVENT_CONTEXT_PTHREAD_ID = 10,
-};
+ * Copyright (C) 2011 EfficiOS Inc.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ */
+
+#ifndef LTTNG_H
+#define LTTNG_H
+
+#include <lttng/lttng-export.h>
+
+/* Error codes that can be returned by API calls */
+#include <lttng/lttng-error.h>
+
+/* Include every LTTng ABI/API available. */
+#include <lttng/action/action.h>
+#include <lttng/action/list.h>
+#include <lttng/action/notify.h>
+#include <lttng/action/path.h>
+#include <lttng/action/rate-policy.h>
+#include <lttng/action/rotate-session.h>
+#include <lttng/action/snapshot-session.h>
+#include <lttng/action/start-session.h>
+#include <lttng/action/stop-session.h>
+#include <lttng/channel.h>
+#include <lttng/clear-handle.h>
+#include <lttng/clear.h>
+#include <lttng/condition/buffer-usage.h>
+#include <lttng/condition/condition.h>
+#include <lttng/condition/evaluation.h>
+#include <lttng/condition/event-rule-matches.h>
+#include <lttng/condition/session-consumed-size.h>
+#include <lttng/condition/session-rotation.h>
+#include <lttng/constant.h>
+#include <lttng/destruction-handle.h>
+#include <lttng/domain.h>
+#include <lttng/endpoint.h>
+#include <lttng/error-query.h>
+#include <lttng/event-expr.h>
+#include <lttng/event-field-value.h>
+#include <lttng/event-rule/event-rule.h>
+#include <lttng/event-rule/jul-logging.h>
+#include <lttng/event-rule/kernel-kprobe.h>
+#include <lttng/event-rule/kernel-syscall.h>
+#include <lttng/event-rule/kernel-tracepoint.h>
+#include <lttng/event-rule/kernel-uprobe.h>
+#include <lttng/event-rule/log4j-logging.h>
+#include <lttng/event-rule/python-logging.h>
+#include <lttng/event-rule/user-tracepoint.h>
+#include <lttng/event.h>
+#include <lttng/handle.h>
+#include <lttng/health.h>
+#include <lttng/kernel-probe.h>
+#include <lttng/kernel.h>
+#include <lttng/load.h>
+#include <lttng/location.h>
+#include <lttng/log-level-rule.h>
+#include <lttng/lttng-error.h>
+#include <lttng/notification/channel.h>
+#include <lttng/notification/notification.h>
+#include <lttng/rotation.h>
+#include <lttng/save.h>
+#include <lttng/session-descriptor.h>
+#include <lttng/session.h>
+#include <lttng/snapshot.h>
+#include <lttng/tracker.h>
+#include <lttng/trigger/trigger.h>
+#include <lttng/userspace-probe.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
enum lttng_calibrate_type {
- LTTNG_CALIBRATE_FUNCTION = 0,
+ LTTNG_CALIBRATE_FUNCTION = 0,
};
-/* Health component for the health check function. */
-enum lttng_health_component {
- LTTNG_HEALTH_CMD,
- LTTNG_HEALTH_APP_MANAGE,
- LTTNG_HEALTH_APP_REG,
- LTTNG_HEALTH_KERNEL,
- LTTNG_HEALTH_CONSUMER,
- LTTNG_HEALTH_ALL,
+/* Machine interface output type */
+enum lttng_mi_output_type {
+ LTTNG_MI_XML = 1 /* XML output */
};
-/*
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_DOMAIN_PADDING1 16
-#define LTTNG_DOMAIN_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
-struct lttng_domain {
- enum lttng_domain_type type;
- char padding[LTTNG_DOMAIN_PADDING1];
-
- union {
- pid_t pid;
- char exec_name[NAME_MAX];
- char padding[LTTNG_DOMAIN_PADDING2];
- } attr;
-};
-
-/*
- * Perf counter attributes
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_PERF_EVENT_PADDING1 16
-struct lttng_event_perf_counter_ctx {
- uint32_t type;
- uint64_t config;
- char name[LTTNG_SYMBOL_NAME_LEN];
-
- char padding[LTTNG_PERF_EVENT_PADDING1];
-};
-
-/*
- * Event/channel context
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_EVENT_CONTEXT_PADDING1 16
-#define LTTNG_EVENT_CONTEXT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
-struct lttng_event_context {
- enum lttng_event_context_type ctx;
- char padding[LTTNG_EVENT_CONTEXT_PADDING1];
-
- union {
- struct lttng_event_perf_counter_ctx perf_counter;
- char padding[LTTNG_EVENT_CONTEXT_PADDING2];
- } u;
-};
-
-/*
- * Event probe.
- *
- * Either addr is used or symbol_name and offset.
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_EVENT_PROBE_PADDING1 16
-struct lttng_event_probe_attr {
- uint64_t addr;
-
- uint64_t offset;
- char symbol_name[LTTNG_SYMBOL_NAME_LEN];
-
- char padding[LTTNG_EVENT_PROBE_PADDING1];
-};
-
-/*
- * Function tracer
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_EVENT_FUNCTION_PADDING1 16
-struct lttng_event_function_attr {
- char symbol_name[LTTNG_SYMBOL_NAME_LEN];
-
- char padding[LTTNG_EVENT_FUNCTION_PADDING1];
-};
-
-/*
- * Generic lttng event
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_EVENT_PADDING1 15
-#define LTTNG_EVENT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
-struct lttng_event {
- enum lttng_event_type type;
- char name[LTTNG_SYMBOL_NAME_LEN];
-
- enum lttng_loglevel_type loglevel_type;
- int loglevel;
-
- int32_t enabled; /* Does not apply: -1 */
- pid_t pid;
- unsigned char filter; /* filter enabled ? */
-
- char padding[LTTNG_EVENT_PADDING1];
-
- /* Per event type configuration */
- union {
- struct lttng_event_probe_attr probe;
- struct lttng_event_function_attr ftrace;
-
- char padding[LTTNG_EVENT_PADDING2];
- } attr;
-};
-
-enum lttng_event_field_type {
- LTTNG_EVENT_FIELD_OTHER = 0,
- LTTNG_EVENT_FIELD_INTEGER = 1,
- LTTNG_EVENT_FIELD_ENUM = 2,
- LTTNG_EVENT_FIELD_FLOAT = 3,
- LTTNG_EVENT_FIELD_STRING = 4,
-};
-
-#define LTTNG_EVENT_FIELD_PADDING LTTNG_SYMBOL_NAME_LEN + 32
-struct lttng_event_field {
- char field_name[LTTNG_SYMBOL_NAME_LEN];
- enum lttng_event_field_type type;
- char padding[LTTNG_EVENT_FIELD_PADDING];
- struct lttng_event event;
-};
-
-/*
- * Tracer channel attributes. For both kernel and user-space.
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 32
-struct lttng_channel_attr {
- int overwrite; /* 1: overwrite, 0: discard */
- uint64_t subbuf_size; /* bytes */
- uint64_t num_subbuf; /* power of 2 */
- unsigned int switch_timer_interval; /* usec */
- unsigned int read_timer_interval; /* usec */
- enum lttng_event_output output; /* splice, mmap */
-
- char padding[LTTNG_CHANNEL_ATTR_PADDING1];
-};
-
-/*
- * Channel information structure. For both kernel and user-space.
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_CHANNEL_PADDING1 16
-struct lttng_channel {
- char name[LTTNG_SYMBOL_NAME_LEN];
- uint32_t enabled;
- struct lttng_channel_attr attr;
-
- char padding[LTTNG_CHANNEL_PADDING1];
-};
-
-#define LTTNG_CALIBRATE_PADDING1 16
+#define LTTNG_CALIBRATE_PADDING1 16
struct lttng_calibrate {
enum lttng_calibrate_type type;
char padding[LTTNG_CALIBRATE_PADDING1];
};
-/*
- * Basic session information.
- *
- * This is an 'output data' meaning that it only comes *from* the session
- * daemon *to* the lttng client. It's basically a 'human' representation of
- * tracing entities (here a session).
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_SESSION_PADDING1 16
-struct lttng_session {
- char name[NAME_MAX];
- /* The path where traces are written */
- char path[PATH_MAX];
- uint32_t enabled; /* enabled/started: 1, disabled/stopped: 0 */
-
- char padding[LTTNG_SESSION_PADDING1];
-};
-
-/*
- * Handle used as a context for commands.
- *
- * The structures should be initialized to zero before use.
- */
-#define LTTNG_HANDLE_PADDING1 16
-struct lttng_handle {
- char session_name[NAME_MAX];
- struct lttng_domain domain;
-
- char padding[LTTNG_HANDLE_PADDING1];
-};
-
-/*
- * Public LTTng control API
- *
- * For functions having an lttng domain type as parameter, if a bad value is
- * given, NO default is applied and an error is returned.
- *
- * On success, all functions of the API return 0 or the size of the allocated
- * array (in bytes).
- *
- * On error, a negative value is returned being a specific lttng-tools error
- * code which can be humanly interpreted with lttng_strerror(err).
- *
- * Exceptions to this are noted below.
- */
+/*!
+@brief
+ Returns whether or not liblttng-ctl is able to connect to a
+ listening session daemon.
-/*
- * Create a handle used as a context for every request made to the library.
- *
- * This handle contains the session name and lttng domain on which the command
- * will be executed.
- * The returned pointer will be NULL in case of malloc() error.
- */
-extern struct lttng_handle *lttng_create_handle(const char *session_name,
- struct lttng_domain *domain);
+@ingroup api_gen
-/*
- * Destroy a handle. This will simply free(3) the data pointer returned by
- * lttng_create_handle(), rendering it unusable.
- */
-extern void lttng_destroy_handle(struct lttng_handle *handle);
+How this function tries to
+\ref api-gen-sessiond-conn "connect to a session daemon" depends on the
+current Unix tracing group (initially \c tracing) of the library. Set
+the tracing group with lttng_set_tracing_group().
-/*
- * Create a tracing session using a name and an optional URL.
- *
- * If _url_ is NULL, no consumer is created for the session.
- */
-extern int lttng_create_session(const char *name, const char *url);
+@returns
+ @parblock
+ One of:
-/*
- * Destroy a tracing session.
- *
- * The session will not be usable anymore, tracing will be stopped for all
- * registered traces, and the tracing buffers will be flushed.
- */
-extern int lttng_destroy_session(const char *name);
+ <dl>
+ <dt>1</dt>
+ <dd>
+ liblttng-ctl is able to connect to a session daemon.
-/*
- * List all the tracing sessions.
- *
- * Return the size (number of entries) of the "lttng_session" array. Caller
- * must free(3).
- */
-extern int lttng_list_sessions(struct lttng_session **sessions);
+ <dt>0
+ <dd>
+ liblttng-ctl isn't able to connect to a session daemon.
-/*
- * List the registered domain(s) of a session.
- *
- * Return the size (number of entries) of the "lttng_domain" array. Caller
- * must free(3).
- */
-extern int lttng_list_domains(const char *session_name,
- struct lttng_domain **domains);
+ <dt>Negative value
+ <dd>
+ Error: a negative #lttng_error_code enumerator.
+ </dl>
+ @endparblock
-/*
- * List the channel(s) of a session.
- *
- * Return the size (number of entries) of the "lttng_channel" array. Caller
- * must free(3).
- */
-extern int lttng_list_channels(struct lttng_handle *handle,
- struct lttng_channel **channels);
+@sa lttng_set_tracing_group() --
+ Sets the current Unix tracing group of liblttng-ctl.
+*/
+LTTNG_EXPORT extern int lttng_session_daemon_alive(void);
-/*
- * List the event(s) of a session channel.
- *
- * Return the size (number of entries) of the "lttng_event" array.
- * Caller must free(3).
- */
-extern int lttng_list_events(struct lttng_handle *handle,
- const char *channel_name, struct lttng_event **events);
+/*!
+@brief
+ Sets the current Unix tracing group of liblttng-ctl to \lt_p{group}.
-/*
- * List the available tracepoints of a specific lttng domain.
- *
- * Return the size (number of entries) of the "lttng_event" array.
- * Caller must free(3).
- */
-extern int lttng_list_tracepoints(struct lttng_handle *handle,
- struct lttng_event **events);
+@ingroup api_gen
-/*
- * List the available tracepoints fields of a specific lttng domain.
- *
- * Return the size (number of entries) of the "lttng_event_field" array.
- * Caller must free(3).
- */
-extern int lttng_list_tracepoint_fields(struct lttng_handle *handle,
- struct lttng_event_field **fields);
+How the liblttng-ctl functions
+\ref api-gen-sessiond-conn "connect to a session daemon" depends on
+the current Unix tracing group (initially \c tracing) of the library.
-/*
- * Check if a session daemon is alive.
- *
- * Return 1 if alive or 0 if not. On error returns a negative value.
- */
-extern int lttng_session_daemon_alive(void);
+@param[in] group
+ New Unix tracing group of liblttng-ctl.
-/*
- * Set the tracing group for the *current* flow of execution.
- *
- * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
- */
-extern int lttng_set_tracing_group(const char *name);
+@returns
+ 0 on success, or a \em negative #lttng_error_code enumerator
+ otherwise.
-/*
- * Return a human-readable error message for an lttng-tools error code.
- *
- * Parameter MUST be a negative value or else you'll get a generic message.
- */
-extern const char *lttng_strerror(int code);
+@lt_pre_not_null{group}
+@pre
+ \lt_p{group} names an existing Unix group.
+*/
+LTTNG_EXPORT extern int lttng_set_tracing_group(const char *group);
/*
* This call registers an "outside consumer" for a session and an lttng domain.
* No consumer will be spawned and all fds/commands will go through the socket
* path given (socket_path).
*
- * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
- * command socket. The error socket is not supported yet for roaming consumers.
- */
-extern int lttng_register_consumer(struct lttng_handle *handle,
- const char *socket_path);
+ * NOTE that this is not recommended unless you absolutely know what you are
+ * doing.
+ *
+ * Return 0 on success else a negative LTTng error code.
+ */
+LTTNG_EXPORT extern int lttng_register_consumer(struct lttng_handle *handle,
+ const char *socket_path);
+
+/*!
+@brief
+ Makes the recording session named \lt_p{session_name} active,
+ starting all the tracers for its
+ \ref api-channel-channel "channels".
+
+@ingroup api_session
+
+@note
+ An #LTTNG_ACTION_TYPE_START_SESSION trigger action can also activate
+ (start) a recording session.
+
+@param[in] session_name
+ Name of the recording session to activate/start.
+
+@returns
+ 0 on success, or a \em negative #lttng_error_code enumerator
+ otherwise.
+
+@lt_pre_conn
+@lt_pre_not_null{session_name}
+@lt_pre_sess_exists{session_name}
+@lt_pre_sess_inactive{session_name}
+
+@sa lttng_stop_tracing() --
+ Stops a recording session.
+@sa \lt_man{lttng-start,1}
+*/
+LTTNG_EXPORT extern int lttng_start_tracing(const char *session_name);
+
+/*!
+@brief
+ Makes the recording session named \lt_p{session_name} inactive,
+ stopping all the tracers for its
+ \ref api-channel-channel "channels", blocking until the operation
+ completes.
+
+@ingroup api_session
+
+This function blocks until the trace data of the
+recording session named \lt_p{session_name} is valid. Use
+lttng_stop_tracing_no_wait() to avoid a blocking call.
+
+If LTTng \ref api_session_rotation "archived the current trace chunk"
+of the recording session named \lt_p{session_name} at least
+once during its lifetime, then this function renames the current trace
+chunk subdirectory. Although it's safe to
+read the content of this renamed subdirectory while the recording
+session remains inactive, it's \em not a trace chunk archive: you need to
+\link lttng_destroy_session_ext() destroy\endlink the recording session
+or a rotation needs to occur to archive it.
+
+@note
+ An #LTTNG_ACTION_TYPE_STOP_SESSION trigger action can also
+ deactivate (stop) a recording session.
+
+@param[in] session_name
+ Name of the recording session to deactivate/stop.
+
+@returns
+ 0 on success, or a \em negative #lttng_error_code enumerator
+ otherwise.
+
+@lt_pre_conn
+@lt_pre_not_null{session_name}
+@lt_pre_sess_exists{session_name}
+@lt_pre_sess_active{session_name}
+
+@sa lttng_stop_tracing_no_wait() --
+ Deactivates a recording session without waiting for the operation
+ to complete.
+@sa lttng_start_tracing() --
+ Starts a recording session.
+@sa \lt_man{lttng-stop,1}
+*/
+LTTNG_EXPORT extern int lttng_stop_tracing(const char *session_name);
+
+/*!
+@brief
+ Makes the recording session named \lt_p{session_name} inactive,
+ stopping all the tracers for its
+ \ref api-channel-channel "channels" without waiting for the
+ operation to complete.
+
+@ingroup api_session
+
+Unlike lttng_stop_tracing(), this function does \em not block until
+the operation is complete: it returns immediately. This
+means the traces(s) of the recording session might not be valid when
+this function returns, and there's no way to know when it/they become
+valid.
+
+@note
+ An #LTTNG_ACTION_TYPE_STOP_SESSION trigger action can also
+ deactivate (stop) a recording session.
+
+@param[in] session_name
+ Name of the recording session to deactivate/stop.
+
+@returns
+ 0 on success, or a \em negative #lttng_error_code enumerator
+ otherwise.
+
+@lt_pre_conn
+@lt_pre_not_null{session_name}
+@lt_pre_sess_exists{session_name}
+@lt_pre_sess_active{session_name}
+@pre
+ No deactivation operation is in progress for the recording session
+ named \lt_p{session_name}.
+
+@sa lttng_stop_tracing() --
+ Deactivates a recording session, blocking until the operation
+ completes.
+@sa lttng_start_tracing() --
+ Starts a recording session.
+@sa \lt_man{lttng-stop,1}
+*/
+LTTNG_EXPORT extern int lttng_stop_tracing_no_wait(const char *session_name);
+
+/*
+ * Deprecated: As of LTTng 2.9, this function always returns
+ * -LTTNG_ERR_UND.
+ */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wshadow"
+LTTNG_EXPORT extern int lttng_calibrate(struct lttng_handle *handle,
+ struct lttng_calibrate *calibrate);
+#pragma GCC diagnostic pop
/*
- * Start tracing for *all* registered traces (kernel and user-space).
- */
-extern int lttng_start_tracing(const char *session_name);
-
-/*
- * Stop tracing for *all* registered traces (kernel and user-space).
- */
-extern int lttng_stop_tracing(const char *session_name);
-
-/*
- * Add context to event(s) for a specific channel (or for all).
+ * Set URL for a consumer for a session and domain.
*
- * If event_name is NULL, the context is applied to all events of the channel.
- * If channel_name is NULL, a lookup of the event's channel is done.
- * If both are NULL, the context is applied to all events of all channels.
- */
-extern int lttng_add_context(struct lttng_handle *handle,
- struct lttng_event_context *ctx, const char *event_name,
- const char *channel_name);
-
-/*
- * Create or enable an event (or events) for a channel.
+ * Both data and control URL must be defined. If both URLs are the same, only
+ * the control URL is used even for network streaming.
*
- * If the event you are trying to enable does not exist, it will be created,
- * else it is enabled.
- * If event_name is NULL, all events are enabled.
- * If channel_name is NULL, the default channel is used (channel0).
- */
-extern int lttng_enable_event(struct lttng_handle *handle,
- struct lttng_event *ev, const char *channel_name);
-
-/*
- * Apply a filter expression to an event.
+ * Default port are 5342 and 5343 respectively for control and data which uses
+ * the TCP protocol.
*
- * If event_name is NULL, the filter is applied to all events of the channel.
- * If channel_name is NULL, a lookup of the event's channel is done.
- * If both are NULL, the filter is applied to all events of all channels.
- */
-extern int lttng_set_event_filter(struct lttng_handle *handle,
- const char *event_name,
- const char *channel_name,
- const char *filter_expression);
-/*
- * Create or enable a channel.
- * The channel name cannot be NULL.
- */
-extern int lttng_enable_channel(struct lttng_handle *handle,
- struct lttng_channel *chan);
-
-/*
- * Disable event(s) of a channel and domain.
+ * URL format: proto://[HOST|IP][:PORT1[:PORT2]][/TRACE_PATH]
*
- * If event_name is NULL, all events are disabled.
- * If channel_name is NULL, the default channel is used (channel0).
- */
-extern int lttng_disable_event(struct lttng_handle *handle,
- const char *name, const char *channel_name);
-
-/*
- * Disable channel.
+ * Possible protocols are:
+ * > file://...
+ * Local filesystem full path.
+ *
+ * > net[6]://...
+ * This will use the default network transport layer which is TCP for both
+ * control (PORT1) and data port (PORT2).
*
- * The channel name cannot be NULL.
+ * > tcp[6]://...
+ * TCP only streaming. For this one, both data and control URL must be given.
+ *
+ * Return 0 on success else a negative LTTng error code.
*/
-extern int lttng_disable_channel(struct lttng_handle *handle,
- const char *name);
+LTTNG_EXPORT extern int
+lttng_set_consumer_url(struct lttng_handle *handle, const char *control_url, const char *data_url);
-/*
- * Calibrate LTTng overhead.
- */
-extern int lttng_calibrate(struct lttng_handle *handle,
- struct lttng_calibrate *calibrate);
+/*!
+@brief
+ Returns whether or not you may read the traces of the recording
+ session named \lt_p{session_name}.
-/*
- * Set the default channel attributes for a specific domain and an allocated
- * lttng_channel_attr pointer.
- *
- * If either or both of the arguments are NULL, nothing happens.
- */
-extern void lttng_channel_set_default_attr(struct lttng_domain *domain,
- struct lttng_channel_attr *attr);
+@ingroup api_session
-/*
- * Set URL for a consumer for a session and domain.
- *
- * Both data and control URL must be defined. If both URLs are the same, only
- * the control URL is used even for network streaming.
- *
- * Default port are 5342 and 5343 respectively for control and data which uses
- * the TCP protocol.
- */
-extern int lttng_set_consumer_url(struct lttng_handle *handle,
- const char *control_url, const char *data_url);
+It's not safe to read the traces of a recording session while
+LTTng is still consuming data from the tracers for its
+\ref api-channel-channel "channels".
-/*
- * Enable the consumer for a session and domain.
- */
-extern int lttng_enable_consumer(struct lttng_handle *handle);
+This function makes it possible to know when LTTng is done consuming
+trace data from tracers for the channels of the recording session
+named \lt_p{session_name}.
-/*
- * Disable consumer for a session and domain.
- */
-extern int lttng_disable_consumer(struct lttng_handle *handle);
+@param[in] session_name
+ Name of the recording session of which get whether or not
+ you may read its traces.
-/*
- * Check session daemon health for a specific component.
- *
- * Return 0 if health is OK or 1 if BAD. A returned value of -1 indicate that
- * the control library was not able to connect to the session daemon health
- * socket.
- *
- * Any other positive value is an lttcomm error which can be translate with
- * lttng_strerror().
- */
-extern int lttng_health_check(enum lttng_health_component c);
+@returns
+ @parblock
+ One of:
+
+ <dl>
+ <dt>0
+ <dd>
+ You may read the traces of the recording session named
+ \lt_p{session_name}.
+
+ This remains true as long as the recording session remains
+ \link lttng_session::enabled inactive\endlink (stopped).
-#endif /* _LTTNG_H */
+ <dt>1</dt>
+ <dd>
+ You may \em not read the traces of the recording session named
+ \lt_p{session_name}.
+
+ <dt>Negative value
+ <dd>
+ Error: a negative #lttng_error_code enumerator.
+ </dl>
+ @endparblock
+
+@lt_pre_conn
+@lt_pre_not_null{session_name}
+@lt_pre_sess_exists{session_name}
+@lt_pre_sess_inactive{session_name}
+*/
+LTTNG_EXPORT extern int lttng_data_pending(const char *session_name);
+
+/*
+ * Gets the status of the kernel tracer.
+ *
+ * Sets the value of the argument, which must not be null.
+ */
+LTTNG_EXPORT extern enum lttng_error_code
+lttng_get_kernel_tracer_status(enum lttng_kernel_tracer_status *status);
+
+/*!
+@brief
+ Regenerates the metadata streams of the recording session named
+ \lt_p{session_name}.
+
+@ingroup api_session
+
+@deprecated
+ Use lttng_regenerate_metadata().
+
+@param[in] session_name
+ Name of the recording session of which to regenerate the metadata
+ streams.
+
+@returns
+ 0 on success, or a \em negative #lttng_error_code enumerator
+ otherwise.
+
+@lt_pre_conn
+@lt_pre_not_null{session_name}
+@lt_pre_sess_exists{session_name}
+*/
+/// @cond DEPRECATED
+LTTNG_DEPRECATED()
+/// @endcond
+LTTNG_EXPORT extern int lttng_metadata_regenerate(const char *session_name);
+
+/*!
+@brief
+ Regenerates the metadata streams of the recording session named
+ \lt_p{session_name}.
+
+@ingroup api_session
+
+Use this function to resample the offset between the monotonic clock and
+the wall time of the system, and then regenerate (overwrite) all the
+metadata stream files (local or remote) of the recording session
+named \lt_p{session_name}.
+
+More specifically, you may want to resample the wall time following a
+major <a href="https://en.wikipedia.org/wiki/Network_Time_Protocol">NTP</a>
+correction. As such, LTTng can trace a system booting with an incorrect
+wall time before its wall time is NTP-corrected. Regenerating the
+metadata of a recording session ensures that trace readers
+can accurately determine the event record timestamps relative to the
+Unix epoch.
+
+Note that if you plan to \ref api_session_rotation "rotate" the
+recording session named \lt_p{session_name}, this function only
+regenerates the metadata stream files of the \em current and \em next
+trace chunks.
+
+See the preconditions of this function which show important limitations.
+
+@param[in] session_name
+ Name of the recording session of which to regenerate the metadata
+ streams.
+
+@returns
+ 0 on success, or a \em negative #lttng_error_code enumerator
+ otherwise.
+
+@lt_pre_conn
+@lt_pre_not_null{session_name}
+@lt_pre_sess_exists{session_name}
+@pre
+ The recording session named \lt_p{session_name} was \em not created
+ in \ref api-session-live-mode "live mode".
+@pre
+ All the \ref api-channel-channel "channels" of the recording session
+ named \lt_p{session_name} use a
+ \ref api-channel-per-user-buf "per-user buffering scheme".
+
+@sa lttng_regenerate_statedump() --
+ Regenerates the state dump event records of a recording session.
+@sa \lt_man{lttng-regenerate,1}
+*/
+LTTNG_EXPORT extern int lttng_regenerate_metadata(const char *session_name);
+
+/*!
+@brief
+ Regenerates the state dump event records of the recording session
+ named \lt_p{session_name}.
+
+@ingroup api_session
+
+Use this function to collect up-to-date state dump information and
+append corresponding event records to the
+\ref api-channel-channel "sub-buffers" of the recording session named
+\lt_p{session_name}.
+
+This is particularly useful if you created the recording session in
+\ref api-session-snapshot-mode "snapshot mode"
+or if LTTng \ref api_session_rotation "rotates" trace files for one of
+its \ref api-channel-channel "channels": in both cases, the state dump
+information may be lost.
+
+@param[in] session_name
+ Name of the recording session of which to regenerate the
+ state dump event records.
+
+@returns
+ 0 on success, or a \em negative #lttng_error_code enumerator
+ otherwise.
+
+@lt_pre_conn
+@lt_pre_not_null{session_name}
+@lt_pre_sess_exists{session_name}
+
+@sa lttng_regenerate_metadata() --
+ Regenerates the metadata streams of a recording session.
+@sa \lt_man{lttng-regenerate,1}
+*/
+LTTNG_EXPORT extern int lttng_regenerate_statedump(const char *session_name);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LTTNG_H */
projects / lttng-tools.git / blobdiff