[lttng-ust.git] / include / ust-context-provider.h

/*
 * SPDX-License-Identifier: MIT
 *
 * Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * The context provider feature is part of the ABI and used by the Java jni
 * interface. This header should be moved to the public header directory once
 * some test code and documentation is written.
 */

#ifndef _LTTNG_UST_CONTEXT_PROVIDER_H
#define _LTTNG_UST_CONTEXT_PROVIDER_H

#include <stddef.h>
#include <lttng/ust-events.h>
#include <urcu/hlist.h>

#include "ust-dynamic-type.h"

/*
 * Context value
 *
 * IMPORTANT: this structure is part of the ABI between the probe and
 * UST. Additional selectors may be added in the future, mapping to new
 * union fields, which means the overall size of this structure may
 * increase. This means this structure should never be nested within a
 * public structure interface, nor embedded in an array.
 */

struct lttng_ust_ctx_value {
	enum lttng_ust_dynamic_type sel;	/* Type selector */
	union {
		int64_t s64;
		uint64_t u64;
		const char *str;
		double d;
	} u;
};

/*
 * Context field
 *
 * IMPORTANT: this structure is part of the ABI between the probe and
 * UST. Fields need to be only added at the end, never reordered, never
 * removed.
 *
 * The field @struct_size should be used to determine the size of the
 * structure. It should be queried before using additional fields added
 * at the end of the structure.
 */

struct lttng_ust_ctx_field {
	uint32_t struct_size;
	void *priv;

	struct lttng_ust_event_field *event_field;
	size_t (*get_size)(struct lttng_ust_ctx_field *field, size_t offset);
	void (*record)(struct lttng_ust_ctx_field *field,
		       struct lttng_ust_lib_ring_buffer_ctx *ctx,
		       struct lttng_ust_channel_buffer *chan);
	void (*get_value)(struct lttng_ust_ctx_field *field,
			 struct lttng_ust_ctx_value *value);
	void (*destroy)(struct lttng_ust_ctx_field *field);

	/* End of base ABI. Fields below should be used after checking struct_size. */
};

/*
 * All context fields for a given event/channel
 *
 * IMPORTANT: this structure is part of the ABI between the probe and
 * UST. Fields need to be only added at the end, never reordered, never
 * removed.
 *
 * The field @struct_size should be used to determine the size of the
 * structure. It should be queried before using additional fields added
 * at the end of the structure.
 */

struct lttng_ust_ctx {
	uint32_t struct_size;

	struct lttng_ust_ctx_field **fields;
	unsigned int nr_fields;
	unsigned int allocated_fields;
	unsigned int largest_align;

	/* End of base ABI. Fields below should be used after checking struct_size. */
};

/*
 * Context provider
 *
 * IMPORTANT: this structure is part of the ABI between the probe and
 * UST. Fields need to be only added at the end, never reordered, never
 * removed.
 *
 * The field @struct_size should be used to determine the size of the
 * structure. It should be queried before using additional fields added
 * at the end of the structure.
 */

struct lttng_ust_context_provider {
	uint32_t struct_size;

	char *name;
	size_t (*get_size)(struct lttng_ust_ctx_field *field, size_t offset);
	void (*record)(struct lttng_ust_ctx_field *field,
		       struct lttng_ust_lib_ring_buffer_ctx *ctx,
		       struct lttng_ust_channel_buffer *chan);
	void (*get_value)(struct lttng_ust_ctx_field *field,
			 struct lttng_ust_ctx_value *value);
	struct cds_hlist_node node;

	/* End of base ABI. Fields below should be used after checking struct_size. */
};

int lttng_ust_context_provider_register(struct lttng_ust_context_provider *provider);
void lttng_ust_context_provider_unregister(struct lttng_ust_context_provider *provider);

void lttng_ust_context_set_session_provider(const char *name,
		size_t (*get_size)(struct lttng_ust_ctx_field *field, size_t offset),
		void (*record)(struct lttng_ust_ctx_field *field,
			struct lttng_ust_lib_ring_buffer_ctx *ctx,
			struct lttng_ust_channel_buffer *chan),
		void (*get_value)(struct lttng_ust_ctx_field *field,
			struct lttng_ust_ctx_value *value));

int lttng_ust_add_app_context_to_ctx_rcu(const char *name, struct lttng_ust_ctx **ctx);
int lttng_ust_context_set_provider_rcu(struct lttng_ust_ctx **_ctx,
		const char *name,
		size_t (*get_size)(struct lttng_ust_ctx_field *field, size_t offset),
		void (*record)(struct lttng_ust_ctx_field *field,
			struct lttng_ust_lib_ring_buffer_ctx *ctx,
			struct lttng_ust_channel_buffer *chan),
		void (*get_value)(struct lttng_ust_ctx_field *field,
			struct lttng_ust_ctx_value *value));

#endif /* _LTTNG_UST_CONTEXT_PROVIDER_H */
Commit	Line	Data
53569322	1	/*
c0c0989a	2	* SPDX-License-Identifier: MIT
53569322	3	*
c0c0989a	4	* Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
28b9540b MJ	5	*
	6	* The context provider feature is part of the ABI and used by the Java jni
	7	* interface. This header should be moved to the public header directory once
	8	* some test code and documentation is written.
53569322 MD	9	*/
53569322 MD	10
c0c0989a MJ	11	#ifndef _LTTNG_UST_CONTEXT_PROVIDER_H
	12	#define _LTTNG_UST_CONTEXT_PROVIDER_H
	13
b4051ad8	14	#include <stddef.h>
53569322 MD	15	#include <lttng/ust-events.h>
	16	#include <urcu/hlist.h>
	17
fa194c41 MJ	18	#include "ust-dynamic-type.h"
fa194c41 MJ	19
daacdbfc MD	20	/*
	21	* Context value
	22	*
	23	* IMPORTANT: this structure is part of the ABI between the probe and
35c1f459 MD	24	* UST. Additional selectors may be added in the future, mapping to new
	25	* union fields, which means the overall size of this structure may
	26	* increase. This means this structure should never be nested within a
	27	* public structure interface, nor embedded in an array.
daacdbfc MD	28	*/
	29
	30	struct lttng_ust_ctx_value {
35c1f459	31	enum lttng_ust_dynamic_type sel; /* Type selector */
fa194c41 MJ	32	union {
	33	int64_t s64;
	34	uint64_t u64;
	35	const char *str;
	36	double d;
	37	} u;
	38	};
	39
daacdbfc MD	40	/*
	41	* Context field
	42	*
	43	* IMPORTANT: this structure is part of the ABI between the probe and
	44	* UST. Fields need to be only added at the end, never reordered, never
	45	* removed.
	46	*
	47	* The field @struct_size should be used to determine the size of the
	48	* structure. It should be queried before using additional fields added
	49	* at the end of the structure.
	50	*/
	51
	52	struct lttng_ust_ctx_field {
	53	uint32_t struct_size;
	54	void *priv;
fa194c41	55
daacdbfc MD	56	struct lttng_ust_event_field *event_field;
	57	size_t (get_size)(struct lttng_ust_ctx_field field, size_t offset);
	58	void (record)(struct lttng_ust_ctx_field field,
fa194c41	59	struct lttng_ust_lib_ring_buffer_ctx *ctx,
e7bc0ef6	60	struct lttng_ust_channel_buffer *chan);
daacdbfc MD	61	void (get_value)(struct lttng_ust_ctx_field field,
	62	struct lttng_ust_ctx_value *value);
	63	void (destroy)(struct lttng_ust_ctx_field field);
daacdbfc MD	64
daacdbfc MD	65	/* End of base ABI. Fields below should be used after checking struct_size. */
fa194c41 MJ	66	};
fa194c41 MJ	67
daacdbfc MD	68	/*
	69	* All context fields for a given event/channel
	70	*
	71	* IMPORTANT: this structure is part of the ABI between the probe and
	72	* UST. Fields need to be only added at the end, never reordered, never
	73	* removed.
	74	*
	75	* The field @struct_size should be used to determine the size of the
	76	* structure. It should be queried before using additional fields added
	77	* at the end of the structure.
	78	*/
	79
	80	struct lttng_ust_ctx {
	81	uint32_t struct_size;
	82
	83	struct lttng_ust_ctx_field **fields;
fa194c41 MJ	84	unsigned int nr_fields;
	85	unsigned int allocated_fields;
	86	unsigned int largest_align;
daacdbfc MD	87
daacdbfc MD	88	/* End of base ABI. Fields below should be used after checking struct_size. */
fa194c41 MJ	89	};
fa194c41 MJ	90
daacdbfc MD	91	/*
	92	* Context provider
	93	*
	94	* IMPORTANT: this structure is part of the ABI between the probe and
	95	* UST. Fields need to be only added at the end, never reordered, never
	96	* removed.
	97	*
	98	* The field @struct_size should be used to determine the size of the
	99	* structure. It should be queried before using additional fields added
	100	* at the end of the structure.
	101	*/
	102
53569322	103	struct lttng_ust_context_provider {
daacdbfc MD	104	uint32_t struct_size;
daacdbfc MD	105
53569322	106	char *name;
daacdbfc MD	107	size_t (get_size)(struct lttng_ust_ctx_field field, size_t offset);
daacdbfc MD	108	void (record)(struct lttng_ust_ctx_field field,
53569322	109	struct lttng_ust_lib_ring_buffer_ctx *ctx,
e7bc0ef6	110	struct lttng_ust_channel_buffer *chan);
daacdbfc MD	111	void (get_value)(struct lttng_ust_ctx_field field,
daacdbfc MD	112	struct lttng_ust_ctx_value *value);
53569322	113	struct cds_hlist_node node;
daacdbfc MD	114
daacdbfc MD	115	/* End of base ABI. Fields below should be used after checking struct_size. */
53569322 MD	116	};
	117
	118	int lttng_ust_context_provider_register(struct lttng_ust_context_provider *provider);
	119	void lttng_ust_context_provider_unregister(struct lttng_ust_context_provider *provider);
	120
53569322	121	void lttng_ust_context_set_session_provider(const char *name,
daacdbfc MD	122	size_t (get_size)(struct lttng_ust_ctx_field field, size_t offset),
daacdbfc MD	123	void (record)(struct lttng_ust_ctx_field field,
53569322	124	struct lttng_ust_lib_ring_buffer_ctx *ctx,
e7bc0ef6	125	struct lttng_ust_channel_buffer *chan),
daacdbfc MD	126	void (get_value)(struct lttng_ust_ctx_field field,
daacdbfc MD	127	struct lttng_ust_ctx_value *value));
53569322	128
daacdbfc MD	129	int lttng_ust_add_app_context_to_ctx_rcu(const char name, struct lttng_ust_ctx *ctx);
daacdbfc MD	130	int lttng_ust_context_set_provider_rcu(struct lttng_ust_ctx **_ctx,
53569322	131	const char *name,
daacdbfc MD	132	size_t (get_size)(struct lttng_ust_ctx_field field, size_t offset),
daacdbfc MD	133	void (record)(struct lttng_ust_ctx_field field,
53569322	134	struct lttng_ust_lib_ring_buffer_ctx *ctx,
e7bc0ef6	135	struct lttng_ust_channel_buffer *chan),
daacdbfc MD	136	void (get_value)(struct lttng_ust_ctx_field field,
daacdbfc MD	137	struct lttng_ust_ctx_value *value));
53569322 MD	138
53569322 MD	139	#endif /* _LTTNG_UST_CONTEXT_PROVIDER_H */