X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=include%2Flttng%2Flttng.h;h=825b6682bbee9f39cbaaf2c0093cc1ba3984cdca;hb=HEAD;hp=71c5e820805e2d9db11a3a7c61c532e760f1ba06;hpb=5b97ec606d485e091cf2c2bc06b79f05d18212aa;p=lttng-tools.git diff --git a/include/lttng/lttng.h b/include/lttng/lttng.h index 71c5e8208..6ae331bda 100644 --- a/include/lttng/lttng.h +++ b/include/lttng/lttng.h @@ -1,74 +1,501 @@ /* - * Copyright (C) 2011 - David Goulet + * lttng.h + * + * Linux Trace Toolkit Control Library Header File + * + * Copyright (C) 2011 EfficiOS Inc. + * + * SPDX-License-Identifier: LGPL-2.1-only * - * 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 2 - * 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, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -#ifndef _LIBLTTNGCTL_H -#define _LIBLTTNGCTL_H +#ifndef LTTNG_H +#define LTTNG_H -#include -#include +#include -/* Default unix group name for tracing. - */ -#define DEFAULT_TRACING_GROUP "tracing" +/* Error codes that can be returned by API calls */ +#include -/* Environment variable to set session daemon - * binary path. - */ -#define LTTNG_SESSIOND_PATH_ENV "LTTNG_SESSIOND_PATH" +/* Include every LTTng ABI/API available. */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef __cplusplus +extern "C" { +#endif + +enum lttng_calibrate_type { + LTTNG_CALIBRATE_FUNCTION = 0, +}; + +/* Machine interface output type */ +enum lttng_mi_output_type { + LTTNG_MI_XML = 1 /* XML output */ +}; + +#define LTTNG_CALIBRATE_PADDING1 16 +struct lttng_calibrate { + enum lttng_calibrate_type type; + + char padding[LTTNG_CALIBRATE_PADDING1]; +}; + +/*! +@brief + Returns whether or not liblttng-ctl is able to connect to a + listening session daemon. + +@ingroup api_gen + +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(). + +@returns + @parblock + One of: + +
+
1
+
+ liblttng-ctl is able to connect to a session daemon. + +
0 +
+ liblttng-ctl isn't able to connect to a session daemon. + +
Negative value +
+ Error: a negative #lttng_error_code enumerator. +
+ @endparblock + +@sa lttng_set_tracing_group() -- + Sets the current Unix tracing group of liblttng-ctl. +*/ +LTTNG_EXPORT extern int lttng_session_daemon_alive(void); + +/*! +@brief + Sets the current Unix tracing group of liblttng-ctl to \lt_p{group}. + +@ingroup api_gen + +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. + +@param[in] group + New Unix tracing group of liblttng-ctl. + +@returns + 0 on success, or a \em negative #lttng_error_code enumerator + otherwise. -/* From libuuid +@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 that this is not recommended unless you absolutely know what you are + * doing. + * + * Return 0 on success else a negative LTTng error code. */ -#define UUID_STR_LEN 37 +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. -/* Trace type for lttng_trace. +@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. */ -enum lttng_trace_type { - KERNEL, USERSPACE, -}; +#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 -/* Simple structure representing a 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. + * + * URL format: proto://[HOST|IP][:PORT1[:PORT2]][/TRACE_PATH] + * + * 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). + * + * > 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. */ -struct lttng_session { - char name[NAME_MAX]; - char uuid[UUID_STR_LEN]; -}; +LTTNG_EXPORT extern int +lttng_set_consumer_url(struct lttng_handle *handle, const char *control_url, const char *data_url); -/* Simple trace representation. +/*! +@brief + Returns whether or not you may read the traces of the recording + session named \lt_p{session_name}. + +@ingroup api_session + +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". + +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}. + +@param[in] session_name + Name of the recording session of which get whether or not + you may read its traces. + +@returns + @parblock + One of: + +
+
0 +
+ 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). + +
1
+
+ You may \em not read the traces of the recording session named + \lt_p{session_name}. + +
Negative value +
+ Error: a negative #lttng_error_code enumerator. +
+ @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. */ -struct lttng_trace { - char name[NAME_MAX]; - pid_t pid; - enum lttng_trace_type type; -}; +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 NTP +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 -extern int lttng_create_session(char *name, uuid_t *session_id); -extern int lttng_destroy_session(uuid_t *uuid); -extern int lttng_connect_sessiond(void); -extern int lttng_disconnect_sessiond(void); -extern int lttng_set_tracing_group(const char *name); -extern int lttng_check_session_daemon(void); -extern const char *lttng_get_readable_code(int code); -extern int lttng_ust_list_apps(pid_t **pids); -extern int lttng_list_sessions(struct lttng_session **sessions); -extern int lttng_list_traces(uuid_t *uuid, struct lttng_trace **traces); -extern void lttng_set_current_session_uuid(char *uuid); -extern int lttng_ust_create_trace(pid_t pid); -extern int lttng_ust_start_trace(pid_t pid); -extern int lttng_ust_stop_trace(pid_t pid); - -#endif /* _LIBLTTNGCTL_H */ +#endif /* LTTNG_H */