docs: Add supported versions and fix-backport policy

[lttng-tools.git] / src / bin / lttng-sessiond / consumer.hpp

/*
 * Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

#ifndef _CONSUMER_H
#define _CONSUMER_H

#include "snapshot.hpp"

#include <common/consumer/consumer.hpp>
#include <common/hashtable/hashtable.hpp>

#include <lttng/lttng.h>

#include <algorithm>
#include <urcu/ref.h>

struct snapshot;
struct snapshot_output;
struct ltt_session;

/*
 * Needed until we use C++14, where std::max is constexpr.
 *
 * Use a static_assert so we remember to remove it when we upgrade to a newer
 * C++.
 */
static_assert(__cplusplus == 201103L, "");
template <typename NumericalType>
constexpr NumericalType max_constexpr(NumericalType l, NumericalType r)
{
	return l > r ? l : r;
}

enum consumer_dst_type {
	CONSUMER_DST_LOCAL,
	CONSUMER_DST_NET,
};

enum consumer_trace_chunk_exists_status {
	CONSUMER_TRACE_CHUNK_EXISTS_STATUS_EXISTS_LOCAL,
	CONSUMER_TRACE_CHUNK_EXISTS_STATUS_EXISTS_REMOTE,
	CONSUMER_TRACE_CHUNK_EXISTS_STATUS_UNKNOWN_CHUNK,
};

struct consumer_socket {
	/*
	 * File descriptor. This is just a reference to the consumer data meaning
	 * that every access must be locked and checked for a possible invalid
	 * value.
	 */
	int *fd_ptr;

	/*
	 * To use this socket (send/recv), this lock MUST be acquired.
	 */
	pthread_mutex_t *lock;

	/*
	 * Indicates if the socket was registered by a third part
	 * (REGISTER_CONSUMER) or is the spawn consumer of the session daemon.
	 * During the destroy phase of a consumer output, we close the socket if
	 * this flag is set to 1 since we don't need the fd anymore.
	 */
	unsigned int registered;

	/* Flag if network sockets were sent to the consumer. */
	unsigned int control_sock_sent;
	unsigned int data_sock_sent;

	struct lttng_ht_node_ulong node;

	enum lttng_consumer_type type;
};

struct consumer_data {
	explicit consumer_data(lttng_consumer_type type_) : type(type_)
	{
	}

	enum lttng_consumer_type type;

	/* Mutex to control consumerd pid assignation */
	pthread_mutex_t pid_mutex = PTHREAD_MUTEX_INITIALIZER;
	pid_t pid = 0;

	int err_sock = -1;
	/* These two sockets uses the cmd_unix_sock_path. */
	int cmd_sock = -1;
	/*
	 * Write-end of the channel monitoring pipe to be passed to the
	 * consumer.
	 */
	int channel_monitor_pipe = -1;
	/*
	 * The metadata socket object is handled differently and only created
	 * locally in this object thus it's the only reference available in the
	 * session daemon. For that reason, a variable for the fd is required and
	 * the metadata socket fd points to it.
	 */
	int metadata_fd = 0;
	struct consumer_socket metadata_sock {};

	/* consumer error and command Unix socket path */
	const char *err_unix_sock_path = nullptr;
	const char *cmd_unix_sock_path = nullptr;

	/*
	 * This lock has two purposes. It protects any change to the consumer
	 * socket and make sure only one thread uses this object for read/write
	 * operations.
	 */
	pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
};

/*
 * Network URIs
 */
struct consumer_net {
	/*
	 * Indicate if URI type is set. Those flags should only be set when the
	 * created URI is done AND valid.
	 */
	int control_isset;
	int data_isset;

	/*
	 * The following two URIs MUST have the same destination address for
	 * network streaming to work. Network hop are not yet supported.
	 */

	/* Control path for network streaming. */
	struct lttng_uri control;

	/* Data path for network streaming. */
	struct lttng_uri data;

	/* <hostname>/<session-name> */
	char base_dir[PATH_MAX];
};

/*
 * Consumer output object describing where and how to send data.
 */
struct consumer_output {
	struct urcu_ref ref; /* Refcount */

	/* If the consumer is enabled meaning that should be used */
	bool enabled;
	enum consumer_dst_type type;

	/*
	 * The net_seq_index is the index of the network stream on the consumer
	 * side. It tells the consumer which streams goes to which relayd with this
	 * index. The relayd sockets are index with it on the consumer side.
	 */
	uint64_t net_seq_index;
	/* Store the relay protocol in use if the session is remote. */
	uint32_t relay_major_version;
	uint32_t relay_minor_version;

	/* True if relayd supports the clear feature. */
	bool relay_allows_clear;

	/*
	 * Subdirectory path name used for both local and network
	 * consumer ("kernel", "ust", or empty).
	 */
	char domain_subdir[max_constexpr(sizeof(DEFAULT_KERNEL_TRACE_DIR),
					 sizeof(DEFAULT_UST_TRACE_DIR))];

	/*
	 * Hashtable of consumer_socket index by the file descriptor value. For
	 * multiarch consumer support, we can have more than one consumer (ex:
	 * 32 and 64 bit).
	 */
	struct lttng_ht *socks;

	/* Tell if this output is used for snapshot. */
	unsigned int snapshot:1;

	union {
		char session_root_path[LTTNG_PATH_MAX];
		struct consumer_net net;
	} dst;

	/*
	 * Sub-directory below the session_root_path where the next chunk of
	 * trace will be stored (\0 before the first session rotation).
	 */
	char chunk_path[LTTNG_PATH_MAX];
};

struct consumer_socket *consumer_find_socket(int key, const struct consumer_output *consumer);
struct consumer_socket *consumer_find_socket_by_bitness(int bits,
							const struct consumer_output *consumer);
struct consumer_socket *consumer_allocate_socket(int *fd);
void consumer_add_socket(struct consumer_socket *sock, struct consumer_output *consumer);
void consumer_del_socket(struct consumer_socket *sock, struct consumer_output *consumer);
void consumer_destroy_socket(struct consumer_socket *sock);
int consumer_copy_sockets(struct consumer_output *dst, struct consumer_output *src);
void consumer_destroy_output_sockets(struct consumer_output *obj);
int consumer_socket_send(struct consumer_socket *socket, const void *msg, size_t len);
int consumer_socket_recv(struct consumer_socket *socket, void *msg, size_t len);

struct consumer_output *consumer_create_output(enum consumer_dst_type type);
struct consumer_output *consumer_copy_output(struct consumer_output *obj);
void consumer_output_get(struct consumer_output *obj);
void consumer_output_put(struct consumer_output *obj);
int consumer_set_network_uri(const struct ltt_session *session,
			     struct consumer_output *obj,
			     struct lttng_uri *uri);
int consumer_send_fds(struct consumer_socket *sock, const int *fds, size_t nb_fd);
int consumer_send_msg(struct consumer_socket *sock, const struct lttcomm_consumer_msg *msg);
int consumer_send_stream(struct consumer_socket *sock,
			 struct consumer_output *dst,
			 struct lttcomm_consumer_msg *msg,
			 const int *fds,
			 size_t nb_fd);
int consumer_send_channel(struct consumer_socket *sock, struct lttcomm_consumer_msg *msg);
int consumer_send_relayd_socket(struct consumer_socket *consumer_sock,
				struct lttcomm_relayd_sock *rsock,
				struct consumer_output *consumer,
				enum lttng_stream_type type,
				uint64_t session_id,
				const char *session_name,
				const char *hostname,
				const char *base_path,
				int session_live_timer,
				const uint64_t *current_chunk_id,
				time_t session_creation_time,
				bool session_name_contains_creation_time);
int consumer_send_channel_monitor_pipe(struct consumer_socket *consumer_sock, int pipe);
int consumer_send_destroy_relayd(struct consumer_socket *sock, struct consumer_output *consumer);
int consumer_recv_status_reply(struct consumer_socket *sock);
int consumer_recv_status_channel(struct consumer_socket *sock,
				 uint64_t *key,
				 unsigned int *stream_count);
void consumer_output_send_destroy_relayd(struct consumer_output *consumer);
int consumer_create_socket(struct consumer_data *data, struct consumer_output *output);

void consumer_init_ask_channel_comm_msg(struct lttcomm_consumer_msg *msg,
					uint64_t subbuf_size,
					uint64_t num_subbuf,
					int overwrite,
					unsigned int switch_timer_interval,
					unsigned int read_timer_interval,
					unsigned int live_timer_interval,
					bool is_in_live_session,
					unsigned int monitor_timer_interval,
					int output,
					int type,
					uint64_t session_id,
					const char *pathname,
					const char *name,
					uint64_t relayd_id,
					uint64_t key,
					const lttng_uuid& uuid,
					uint32_t chan_id,
					uint64_t tracefile_size,
					uint64_t tracefile_count,
					uint64_t session_id_per_pid,
					unsigned int monitor,
					uint32_t ust_app_uid,
					int64_t blocking_timeout,
					const char *root_shm_path,
					const char *shm_path,
					struct lttng_trace_chunk *trace_chunk,
					const struct lttng_credentials *buffer_credentials);
void consumer_init_add_stream_comm_msg(struct lttcomm_consumer_msg *msg,
				       uint64_t channel_key,
				       uint64_t stream_key,
				       int32_t cpu);
void consumer_init_streams_sent_comm_msg(struct lttcomm_consumer_msg *msg,
					 enum lttng_consumer_command cmd,
					 uint64_t channel_key,
					 uint64_t net_seq_idx);
void consumer_init_add_channel_comm_msg(struct lttcomm_consumer_msg *msg,
					uint64_t channel_key,
					uint64_t session_id,
					const char *pathname,
					uint64_t relayd_id,
					const char *name,
					unsigned int nb_init_streams,
					enum lttng_event_output output,
					int type,
					uint64_t tracefile_size,
					uint64_t tracefile_count,
					unsigned int monitor,
					unsigned int live_timer_interval,
					bool is_in_live_session,
					unsigned int monitor_timer_interval,
					struct lttng_trace_chunk *trace_chunk);
int consumer_is_data_pending(uint64_t session_id, struct consumer_output *consumer);
int consumer_close_metadata(struct consumer_socket *socket, uint64_t metadata_key);
int consumer_setup_metadata(struct consumer_socket *socket, uint64_t metadata_key);
int consumer_push_metadata(struct consumer_socket *socket,
			   uint64_t metadata_key,
			   char *metadata_str,
			   size_t len,
			   size_t target_offset,
			   uint64_t version);
int consumer_flush_channel(struct consumer_socket *socket, uint64_t key);
int consumer_clear_quiescent_channel(struct consumer_socket *socket, uint64_t key);
int consumer_get_discarded_events(uint64_t session_id,
				  uint64_t channel_key,
				  struct consumer_output *consumer,
				  uint64_t *discarded);
int consumer_get_lost_packets(uint64_t session_id,
			      uint64_t channel_key,
			      struct consumer_output *consumer,
			      uint64_t *lost);

/* Snapshot command. */
enum lttng_error_code consumer_snapshot_channel(struct consumer_socket *socket,
						uint64_t key,
						const struct consumer_output *output,
						int metadata,
						const char *channel_path,
						uint64_t nb_packets_per_stream);

/* Rotation commands. */
int consumer_rotate_channel(struct consumer_socket *socket,
			    uint64_t key,
			    struct consumer_output *output,
			    bool is_metadata_channel);
int consumer_init(struct consumer_socket *socket, const lttng_uuid& sessiond_uuid);

int consumer_create_trace_chunk(struct consumer_socket *socket,
				uint64_t relayd_id,
				uint64_t session_id,
				struct lttng_trace_chunk *chunk,
				const char *domain_subdir);
int consumer_close_trace_chunk(struct consumer_socket *socket,
			       uint64_t relayd_id,
			       uint64_t session_id,
			       struct lttng_trace_chunk *chunk,
			       char *closed_trace_chunk_path);
int consumer_trace_chunk_exists(struct consumer_socket *socket,
				uint64_t relayd_id,
				uint64_t session_id,
				struct lttng_trace_chunk *chunk,
				enum consumer_trace_chunk_exists_status *result);
int consumer_open_channel_packets(struct consumer_socket *socket, uint64_t key);

char *setup_channel_trace_path(struct consumer_output *consumer,
			       const char *session_path,
			       size_t *consumer_path_offset);

/* Clear command */
int consumer_clear_channel(struct consumer_socket *socket, uint64_t key);

#endif /* _CONSUMER_H */