[lttng-tools.git] / src / common / actions / snapshot-session.c

/*
 * Copyright (C) 2019 Simon Marchi <simon.marchi@efficios.com>
 *
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 */

#include <assert.h>
#include <common/error.h>
#include <common/macros.h>
#include <common/payload-view.h>
#include <common/payload.h>
#include <common/snapshot.h>
#include <inttypes.h>
#include <lttng/action/action-internal.h>
#include <lttng/action/firing-policy-internal.h>
#include <lttng/action/firing-policy.h>
#include <lttng/action/snapshot-session-internal.h>
#include <lttng/action/snapshot-session.h>
#include <lttng/snapshot-internal.h>
#include <lttng/snapshot.h>

#define IS_SNAPSHOT_SESSION_ACTION(action) \
	(lttng_action_get_type(action) == LTTNG_ACTION_TYPE_SNAPSHOT_SESSION)

struct lttng_action_snapshot_session {
	struct lttng_action parent;

	/* Owned by this. */
	char *session_name;

	/*
	 * When non-NULL, use this custom output when taking the snapshot,
	 * rather than the session's registered snapshot output.
	 *
	 * Owned by this.
	 */
	struct lttng_snapshot_output *output;
	struct lttng_firing_policy *policy;
};

struct lttng_action_snapshot_session_comm {
	/* All string lengths include the trailing \0. */
	uint32_t session_name_len;
	uint32_t snapshot_output_len;
	uint32_t firing_policy_len;

	/*
	 * Variable data (all strings are null-terminated):
	 *
	 *  - session name string
	 *  - snapshot output object
	 *  - policy object
	 */
	char data[];
} LTTNG_PACKED;

static struct lttng_action_snapshot_session *
action_snapshot_session_from_action(struct lttng_action *action)
{
	assert(action);

	return container_of(
			action, struct lttng_action_snapshot_session, parent);
}

static const struct lttng_action_snapshot_session *
action_snapshot_session_from_action_const(const struct lttng_action *action)
{
	assert(action);

	return container_of(
			action, struct lttng_action_snapshot_session, parent);
}

static bool lttng_action_snapshot_session_validate(struct lttng_action *action)
{
	bool valid = false;
	struct lttng_action_snapshot_session *action_snapshot_session;

	if (!action) {
		goto end;
	}

	action_snapshot_session = action_snapshot_session_from_action(action);

	/* A non-empty session name is mandatory. */
	if (!action_snapshot_session->session_name ||
			strlen(action_snapshot_session->session_name) == 0) {
		goto end;
	}

	if (action_snapshot_session->output &&
			!lttng_snapshot_output_validate(action_snapshot_session->output)) {
		goto end;
	}

	valid = true;
end:
	return valid;
}

static bool lttng_action_snapshot_session_is_equal(
		const struct lttng_action *_a, const struct lttng_action *_b)
{
	bool is_equal = false;
	const struct lttng_action_snapshot_session *a, *b;

	a = action_snapshot_session_from_action_const(_a);
	b = action_snapshot_session_from_action_const(_b);

	/* Action is not valid if this is not true. */
	assert(a->session_name);
	assert(b->session_name);
	if (strcmp(a->session_name, b->session_name)) {
		goto end;
	}

	if (a->output && b->output &&
			!lttng_snapshot_output_is_equal(a->output, b->output)) {
		goto end;
	} else if (!!a->output != !!b->output) {
		goto end;
	}

	is_equal = lttng_firing_policy_is_equal(a->policy, b->policy);
end:
	return is_equal;
}

static size_t serialize_strlen(const char *str)
{
	return str ? strlen(str) + 1 : 0;
}

static int lttng_action_snapshot_session_serialize(
		struct lttng_action *action, struct lttng_payload *payload)
{
	struct lttng_action_snapshot_session *action_snapshot_session;
	struct lttng_action_snapshot_session_comm comm = {};
	int ret;
	size_t size_before_comm;

	assert(action);
	assert(payload);

	size_before_comm = payload->buffer.size;

	action_snapshot_session = action_snapshot_session_from_action(action);
	comm.session_name_len =
		serialize_strlen(action_snapshot_session->session_name);

	/* Add header. */
	ret = lttng_dynamic_buffer_append(
			&payload->buffer, &comm, sizeof(comm));
	if (ret) {
		goto end;
	}

	assert(action_snapshot_session->session_name);
	DBG("Serializing snapshot session action: session-name: %s",
			action_snapshot_session->session_name);

	/* Add session name. */
	ret = lttng_dynamic_buffer_append(&payload->buffer,
			action_snapshot_session->session_name,
			comm.session_name_len);
	if (ret) {
		goto end;
	}

	/* Serialize the snapshot output object, if any. */
	if (action_snapshot_session->output) {
		const size_t size_before_output = payload->buffer.size;
		struct lttng_action_snapshot_session_comm *comm_in_payload;

		ret = lttng_snapshot_output_serialize(
				action_snapshot_session->output,
				payload);
		if (ret) {
			goto end;
		}

		comm_in_payload = (typeof(comm_in_payload))(
				payload->buffer.data + size_before_comm);
		/* Adjust action length in header. */
		comm_in_payload->snapshot_output_len =
				payload->buffer.size - size_before_output;
	}

	/* Serialize the firing policy. */
	{
		const size_t size_before_output = payload->buffer.size;
		struct lttng_action_snapshot_session_comm *comm_in_payload;

		ret = lttng_firing_policy_serialize(
				action_snapshot_session->policy, payload);
		if (ret) {
			ret = -1;
			goto end;
		}

		comm_in_payload = (typeof(comm_in_payload))(
				payload->buffer.data + size_before_comm);
		/* Adjust firing policy length in header. */
		comm_in_payload->firing_policy_len =
				payload->buffer.size - size_before_output;
	}

end:
	return ret;
}

static void lttng_action_snapshot_session_destroy(struct lttng_action *action)
{
	struct lttng_action_snapshot_session *action_snapshot_session;

	if (!action) {
		goto end;
	}

	action_snapshot_session = action_snapshot_session_from_action(action);

	free(action_snapshot_session->session_name);
	lttng_snapshot_output_destroy(action_snapshot_session->output);
	lttng_firing_policy_destroy(action_snapshot_session->policy);
	free(action_snapshot_session);

end:
	return;
}

ssize_t lttng_action_snapshot_session_create_from_payload(
		struct lttng_payload_view *view,
		struct lttng_action **p_action)
{
	ssize_t consumed_len;
	const char *variable_data;
	struct lttng_action *action;
	enum lttng_action_status status;
	struct lttng_snapshot_output *snapshot_output = NULL;
	struct lttng_firing_policy *policy = NULL;
	const struct lttng_action_snapshot_session_comm *comm;
	const struct lttng_payload_view snapshot_session_comm_view =
			lttng_payload_view_from_view(
				view, 0, sizeof(*comm));

	action = lttng_action_snapshot_session_create();
	if (!action) {
		goto error;
	}

	if (!lttng_payload_view_is_valid(&snapshot_session_comm_view)) {
		/* Payload not large enough to contain the header. */
		goto error;
	}

	comm = (typeof(comm)) snapshot_session_comm_view.buffer.data;
	variable_data = (const char *) &comm->data;

	consumed_len = sizeof(struct lttng_action_snapshot_session_comm);

	if (!lttng_buffer_view_contains_string(
			&view->buffer, variable_data, comm->session_name_len)) {
		goto error;
	}

	status = lttng_action_snapshot_session_set_session_name(
			action, variable_data);
	if (status != LTTNG_ACTION_STATUS_OK) {
		goto error;
	}

	variable_data += comm->session_name_len;
	consumed_len += comm->session_name_len;

	/* If there is a snapshot output object, deserialize it. */
	if (comm->snapshot_output_len > 0) {
		ssize_t snapshot_output_consumed_len;
		enum lttng_action_status action_status;
		struct lttng_payload_view snapshot_output_buffer_view =
			lttng_payload_view_from_view(view, consumed_len,
				comm->snapshot_output_len);

		if (!lttng_payload_view_is_valid(&snapshot_output_buffer_view)) {
			ERR("Failed to create buffer view for snapshot output.");
			goto error;
		}

		snapshot_output_consumed_len =
				lttng_snapshot_output_create_from_payload(
						&snapshot_output_buffer_view,
						&snapshot_output);
		if (snapshot_output_consumed_len != comm->snapshot_output_len) {
			ERR("Failed to deserialize snapshot output object: "
					"consumed-len: %zd, expected-len: %" PRIu32,
					snapshot_output_consumed_len,
					comm->snapshot_output_len);
			goto error;
		}

		action_status = lttng_action_snapshot_session_set_output(
			action, snapshot_output);
		if (action_status != LTTNG_ACTION_STATUS_OK) {
			goto error;
		}

		/* Ownership has been transferred to the action. */
		snapshot_output = NULL;
	}

	variable_data += comm->snapshot_output_len;
	consumed_len += comm->snapshot_output_len;

	/* Firing policy. */
	if (comm->firing_policy_len <= 0) {
		ERR("Firing policy should be present.");
		goto error;
	}
	{
		ssize_t firing_policy_consumed_len;
		struct lttng_payload_view policy_view =
				lttng_payload_view_from_view(view, consumed_len,
						comm->firing_policy_len);

		if (!lttng_payload_view_is_valid(&policy_view)) {
			ERR("Failed to create buffer view for firing policy.");
			goto error;
		}

		firing_policy_consumed_len =
				lttng_firing_policy_create_from_payload(
						&policy_view, &policy);
		if (firing_policy_consumed_len < 0) {
			goto error;
		}

		if (firing_policy_consumed_len != comm->firing_policy_len) {
			ERR("Failed to deserialize firing policy object: "
			    "consumed-len: %zd, expected-len: %" PRIu32,
					firing_policy_consumed_len,
					comm->firing_policy_len);
			goto error;
		}

		status = lttng_action_snapshot_session_set_firing_policy(
				action, policy);
		if (status != LTTNG_ACTION_STATUS_OK) {
			goto error;
		}
	}

	variable_data += comm->firing_policy_len;
	consumed_len += comm->firing_policy_len;

	*p_action = action;
	action = NULL;

	goto end;

error:
	consumed_len = -1;

end:
	lttng_firing_policy_destroy(policy);
	lttng_action_snapshot_session_destroy(action);
	lttng_snapshot_output_destroy(snapshot_output);

	return consumed_len;
}

struct lttng_action *lttng_action_snapshot_session_create(void)
{
	struct lttng_action *action = NULL;
	struct lttng_firing_policy *policy = NULL;
	enum lttng_action_status status;

	/* Create a every N = 1 firing policy. */
	policy = lttng_firing_policy_every_n_create(1);
	if (!policy) {
		goto end;
	}

	action = zmalloc(sizeof(struct lttng_action_snapshot_session));
	if (!action) {
		goto end;
	}

	lttng_action_init(action, LTTNG_ACTION_TYPE_SNAPSHOT_SESSION,
			lttng_action_snapshot_session_validate,
			lttng_action_snapshot_session_serialize,
			lttng_action_snapshot_session_is_equal,
			lttng_action_snapshot_session_destroy);

	status = lttng_action_snapshot_session_set_firing_policy(
			action, policy);
	if (status != LTTNG_ACTION_STATUS_OK) {
		free(action);
		action = NULL;
		goto end;
	}

end:
	lttng_firing_policy_destroy(policy);
	return action;
}

enum lttng_action_status lttng_action_snapshot_session_set_session_name(
		struct lttng_action *action, const char *session_name)
{
	struct lttng_action_snapshot_session *action_snapshot_session;
	enum lttng_action_status status;

	if (!action || !IS_SNAPSHOT_SESSION_ACTION(action) || !session_name ||
			strlen(session_name) == 0) {
		status = LTTNG_ACTION_STATUS_INVALID;
		goto end;
	}

	action_snapshot_session = action_snapshot_session_from_action(action);

	free(action_snapshot_session->session_name);

	action_snapshot_session->session_name = strdup(session_name);
	if (!action_snapshot_session->session_name) {
		status = LTTNG_ACTION_STATUS_ERROR;
		goto end;
	}

	status = LTTNG_ACTION_STATUS_OK;
end:
	return status;
}

enum lttng_action_status lttng_action_snapshot_session_get_session_name(
		const struct lttng_action *action, const char **session_name)
{
	const struct lttng_action_snapshot_session *action_snapshot_session;
	enum lttng_action_status status;

	if (!action || !IS_SNAPSHOT_SESSION_ACTION(action) || !session_name) {
		status = LTTNG_ACTION_STATUS_INVALID;
		goto end;
	}

	action_snapshot_session = action_snapshot_session_from_action_const(action);

	if (action_snapshot_session->session_name) {
		*session_name = action_snapshot_session->session_name;
		status = LTTNG_ACTION_STATUS_OK;
	} else {
		status = LTTNG_ACTION_STATUS_UNSET;
	}

end:

	return status;
}

enum lttng_action_status lttng_action_snapshot_session_set_output(
		struct lttng_action *action,
		struct lttng_snapshot_output *output)
{
	struct lttng_action_snapshot_session *action_snapshot_session;
	enum lttng_action_status status;

	if (!action || !IS_SNAPSHOT_SESSION_ACTION(action) || !output) {
		status = LTTNG_ACTION_STATUS_INVALID;
		goto end;
	}

	action_snapshot_session = action_snapshot_session_from_action(action);

	lttng_snapshot_output_destroy(action_snapshot_session->output);
	action_snapshot_session->output = output;

	status = LTTNG_ACTION_STATUS_OK;

end:
	return status;
}

enum lttng_action_status lttng_action_snapshot_session_get_output(
		const struct lttng_action *action,
		const struct lttng_snapshot_output **output)
{
	const struct lttng_action_snapshot_session *action_snapshot_session;
	enum lttng_action_status status;

	if (!action || !IS_SNAPSHOT_SESSION_ACTION(action)|| !output) {
		status = LTTNG_ACTION_STATUS_INVALID;
		goto end;
	}

	action_snapshot_session = action_snapshot_session_from_action_const(action);

	if (action_snapshot_session->output) {
		*output = action_snapshot_session->output;
		status = LTTNG_ACTION_STATUS_OK;
	} else {
		status = LTTNG_ACTION_STATUS_UNSET;
	}

end:
	return status;
}

enum lttng_action_status lttng_action_snapshot_session_set_firing_policy(
		struct lttng_action *action,
		const struct lttng_firing_policy *policy)
{
	enum lttng_action_status status;
	struct lttng_action_snapshot_session *snapshot_session_action;
	struct lttng_firing_policy *copy = NULL;

	if (!action || !policy || !IS_SNAPSHOT_SESSION_ACTION(action)) {
		status = LTTNG_ACTION_STATUS_INVALID;
		goto end;
	}

	copy = lttng_firing_policy_copy(policy);
	if (!copy) {
		status = LTTNG_ACTION_STATUS_ERROR;
		goto end;
	}

	snapshot_session_action = action_snapshot_session_from_action(action);

	/* Free the previous firing policy .*/
	lttng_firing_policy_destroy(snapshot_session_action->policy);

	/* Assign the policy. */
	snapshot_session_action->policy = copy;
	status = LTTNG_ACTION_STATUS_OK;
	copy = NULL;

end:
	lttng_firing_policy_destroy(copy);
	return status;
}

enum lttng_action_status lttng_action_snapshot_session_get_firing_policy(
		const struct lttng_action *action,
		const struct lttng_firing_policy **policy)
{
	enum lttng_action_status status;
	const struct lttng_action_snapshot_session *snapshot_session_action;

	if (!action || !policy || !IS_SNAPSHOT_SESSION_ACTION(action)) {
		status = LTTNG_ACTION_STATUS_INVALID;
		goto end;
	}

	snapshot_session_action =
			action_snapshot_session_from_action_const(action);

	*policy = snapshot_session_action->policy;
	status = LTTNG_ACTION_STATUS_OK;
end:
	return status;
}
Commit	Line	Data
757c48a2 SM	1	/*
	2	* Copyright (C) 2019 Simon Marchi <simon.marchi@efficios.com>
	3	*
	4	* SPDX-License-Identifier: LGPL-2.1-only
	5	*
	6	*/
	7
	8	#include <assert.h>
	9	#include <common/error.h>
	10	#include <common/macros.h>
9e620ea7	11	#include <common/payload-view.h>
d35c7a38 JR	12	#include <common/payload.h>
	13	#include <common/snapshot.h>
	14	#include <inttypes.h>
757c48a2	15	#include <lttng/action/action-internal.h>
d35c7a38 JR	16	#include <lttng/action/firing-policy-internal.h>
d35c7a38 JR	17	#include <lttng/action/firing-policy.h>
757c48a2 SM	18	#include <lttng/action/snapshot-session-internal.h>
757c48a2 SM	19	#include <lttng/action/snapshot-session.h>
757c48a2	20	#include <lttng/snapshot-internal.h>
d35c7a38	21	#include <lttng/snapshot.h>
757c48a2 SM	22
757c48a2 SM	23	#define IS_SNAPSHOT_SESSION_ACTION(action) \
17182cfd	24	(lttng_action_get_type(action) == LTTNG_ACTION_TYPE_SNAPSHOT_SESSION)
757c48a2 SM	25
	26	struct lttng_action_snapshot_session {
	27	struct lttng_action parent;
	28
	29	/* Owned by this. */
	30	char *session_name;
	31
	32	/*
	33	* When non-NULL, use this custom output when taking the snapshot,
	34	* rather than the session's registered snapshot output.
	35	*
	36	* Owned by this.
	37	*/
	38	struct lttng_snapshot_output *output;
d35c7a38	39	struct lttng_firing_policy *policy;
757c48a2 SM	40	};
	41
	42	struct lttng_action_snapshot_session_comm {
	43	/* All string lengths include the trailing \0. */
	44	uint32_t session_name_len;
	45	uint32_t snapshot_output_len;
d35c7a38	46	uint32_t firing_policy_len;
757c48a2 SM	47
	48	/*
	49	* Variable data (all strings are null-terminated):
	50	*
	51	* - session name string
	52	* - snapshot output object
d35c7a38	53	* - policy object
757c48a2 SM	54	*/
	55	char data[];
	56	} LTTNG_PACKED;
	57
	58	static struct lttng_action_snapshot_session *
	59	action_snapshot_session_from_action(struct lttng_action *action)
	60	{
	61	assert(action);
	62
	63	return container_of(
	64	action, struct lttng_action_snapshot_session, parent);
	65	}
	66
	67	static const struct lttng_action_snapshot_session *
	68	action_snapshot_session_from_action_const(const struct lttng_action *action)
	69	{
	70	assert(action);
	71
	72	return container_of(
	73	action, struct lttng_action_snapshot_session, parent);
	74	}
	75
	76	static bool lttng_action_snapshot_session_validate(struct lttng_action *action)
	77	{
	78	bool valid = false;
	79	struct lttng_action_snapshot_session *action_snapshot_session;
	80
	81	if (!action) {
	82	goto end;
	83	}
	84
	85	action_snapshot_session = action_snapshot_session_from_action(action);
	86
	87	/* A non-empty session name is mandatory. */
	88	if (!action_snapshot_session->session_name \|\|
	89	strlen(action_snapshot_session->session_name) == 0) {
	90	goto end;
	91	}
	92
	93	if (action_snapshot_session->output &&
	94	!lttng_snapshot_output_validate(action_snapshot_session->output)) {
	95	goto end;
	96	}
	97
	98	valid = true;
	99	end:
	100	return valid;
	101	}
	102
	103	static bool lttng_action_snapshot_session_is_equal(
	104	const struct lttng_action _a, const struct lttng_action _b)
	105	{
	106	bool is_equal = false;
	107	const struct lttng_action_snapshot_session a, b;
	108
	109	a = action_snapshot_session_from_action_const(_a);
	110	b = action_snapshot_session_from_action_const(_b);
	111
	112	/* Action is not valid if this is not true. */
	113	assert(a->session_name);
	114	assert(b->session_name);
	115	if (strcmp(a->session_name, b->session_name)) {
	116	goto end;
	117	}
118
119	if (a->output && b->output &&
120	!lttng_snapshot_output_is_equal(a->output, b->output)) {
121	goto end;
122	} else if (!!a->output != !!b->output) {
123	goto end;
124	}
125
d35c7a38	126	is_equal = lttng_firing_policy_is_equal(a->policy, b->policy);
757c48a2 SM	127	end:
	128	return is_equal;
	129	}
	130
0c51e8f3	131	static size_t serialize_strlen(const char *str)
757c48a2	132	{
0c51e8f3	133	return str ? strlen(str) + 1 : 0;
757c48a2 SM	134	}
	135
	136	static int lttng_action_snapshot_session_serialize(
	137	struct lttng_action action, struct lttng_payload payload)
	138	{
	139	struct lttng_action_snapshot_session *action_snapshot_session;
	140	struct lttng_action_snapshot_session_comm comm = {};
	141	int ret;
	142	size_t size_before_comm;
	143
	144	assert(action);
	145	assert(payload);
	146
	147	size_before_comm = payload->buffer.size;
757c48a2 SM	148
	149	action_snapshot_session = action_snapshot_session_from_action(action);
	150	comm.session_name_len =
	151	serialize_strlen(action_snapshot_session->session_name);
	152
	153	/* Add header. */
	154	ret = lttng_dynamic_buffer_append(
	155	&payload->buffer, &comm, sizeof(comm));
	156	if (ret) {
	157	goto end;
	158	}
	159
	160	assert(action_snapshot_session->session_name);
	161	DBG("Serializing snapshot session action: session-name: %s",
	162	action_snapshot_session->session_name);
	163
	164	/* Add session name. */
	165	ret = lttng_dynamic_buffer_append(&payload->buffer,
	166	action_snapshot_session->session_name,
	167	comm.session_name_len);
	168	if (ret) {
	169	goto end;
	170	}
	171
	172	/* Serialize the snapshot output object, if any. */
	173	if (action_snapshot_session->output) {
	174	const size_t size_before_output = payload->buffer.size;
	175	struct lttng_action_snapshot_session_comm *comm_in_payload;
	176
	177	ret = lttng_snapshot_output_serialize(
	178	action_snapshot_session->output,
	179	payload);
	180	if (ret) {
	181	goto end;
	182	}
	183
757c48a2 SM	184	comm_in_payload = (typeof(comm_in_payload))(
757c48a2 SM	185	payload->buffer.data + size_before_comm);
d35c7a38	186	/* Adjust action length in header. */
757c48a2 SM	187	comm_in_payload->snapshot_output_len =
	188	payload->buffer.size - size_before_output;
	189	}
	190
d35c7a38 JR	191	/* Serialize the firing policy. */
	192	{
	193	const size_t size_before_output = payload->buffer.size;
	194	struct lttng_action_snapshot_session_comm *comm_in_payload;
	195
	196	ret = lttng_firing_policy_serialize(
	197	action_snapshot_session->policy, payload);
	198	if (ret) {
	199	ret = -1;
	200	goto end;
	201	}
	202
	203	comm_in_payload = (typeof(comm_in_payload))(
	204	payload->buffer.data + size_before_comm);
	205	/* Adjust firing policy length in header. */
	206	comm_in_payload->firing_policy_len =
	207	payload->buffer.size - size_before_output;
	208	}
	209
757c48a2 SM	210	end:
	211	return ret;
	212	}
	213
	214	static void lttng_action_snapshot_session_destroy(struct lttng_action *action)
	215	{
	216	struct lttng_action_snapshot_session *action_snapshot_session;
	217
	218	if (!action) {
	219	goto end;
	220	}
	221
	222	action_snapshot_session = action_snapshot_session_from_action(action);
	223
	224	free(action_snapshot_session->session_name);
	225	lttng_snapshot_output_destroy(action_snapshot_session->output);
d35c7a38	226	lttng_firing_policy_destroy(action_snapshot_session->policy);
757c48a2 SM	227	free(action_snapshot_session);
	228
	229	end:
	230	return;
	231	}
	232
	233	ssize_t lttng_action_snapshot_session_create_from_payload(
	234	struct lttng_payload_view *view,
	235	struct lttng_action **p_action)
	236	{
	237	ssize_t consumed_len;
757c48a2 SM	238	const char *variable_data;
	239	struct lttng_action *action;
	240	enum lttng_action_status status;
	241	struct lttng_snapshot_output *snapshot_output = NULL;
d35c7a38	242	struct lttng_firing_policy *policy = NULL;
3e6e0df2 JG	243	const struct lttng_action_snapshot_session_comm *comm;
	244	const struct lttng_payload_view snapshot_session_comm_view =
	245	lttng_payload_view_from_view(
	246	view, 0, sizeof(*comm));
757c48a2 SM	247
	248	action = lttng_action_snapshot_session_create();
	249	if (!action) {
	250	goto error;
	251	}
	252
3e6e0df2 JG	253	if (!lttng_payload_view_is_valid(&snapshot_session_comm_view)) {
	254	/* Payload not large enough to contain the header. */
	255	goto error;
	256	}
	257
	258	comm = (typeof(comm)) snapshot_session_comm_view.buffer.data;
757c48a2 SM	259	variable_data = (const char *) &comm->data;
	260
	261	consumed_len = sizeof(struct lttng_action_snapshot_session_comm);
	262
	263	if (!lttng_buffer_view_contains_string(
	264	&view->buffer, variable_data, comm->session_name_len)) {
	265	goto error;
	266	}
	267
	268	status = lttng_action_snapshot_session_set_session_name(
	269	action, variable_data);
	270	if (status != LTTNG_ACTION_STATUS_OK) {
	271	goto error;
	272	}
	273
	274	variable_data += comm->session_name_len;
	275	consumed_len += comm->session_name_len;
	276
	277	/* If there is a snapshot output object, deserialize it. */
	278	if (comm->snapshot_output_len > 0) {
	279	ssize_t snapshot_output_consumed_len;
	280	enum lttng_action_status action_status;
	281	struct lttng_payload_view snapshot_output_buffer_view =
	282	lttng_payload_view_from_view(view, consumed_len,
	283	comm->snapshot_output_len);
	284
3e6e0df2	285	if (!lttng_payload_view_is_valid(&snapshot_output_buffer_view)) {
0c51e8f3	286	ERR("Failed to create buffer view for snapshot output.");
757c48a2 SM	287	goto error;
	288	}
	289
	290	snapshot_output_consumed_len =
	291	lttng_snapshot_output_create_from_payload(
	292	&snapshot_output_buffer_view,
	293	&snapshot_output);
	294	if (snapshot_output_consumed_len != comm->snapshot_output_len) {
0c51e8f3	295	ERR("Failed to deserialize snapshot output object: "
757c48a2 SM	296	"consumed-len: %zd, expected-len: %" PRIu32,
	297	snapshot_output_consumed_len,
	298	comm->snapshot_output_len);
	299	goto error;
	300	}
	301
	302	action_status = lttng_action_snapshot_session_set_output(
	303	action, snapshot_output);
	304	if (action_status != LTTNG_ACTION_STATUS_OK) {
	305	goto error;
	306	}
	307
	308	/* Ownership has been transferred to the action. */
	309	snapshot_output = NULL;
	310	}
	311
	312	variable_data += comm->snapshot_output_len;
	313	consumed_len += comm->snapshot_output_len;
d35c7a38 JR	314
	315	/* Firing policy. */
	316	if (comm->firing_policy_len <= 0) {
	317	ERR("Firing policy should be present.");
	318	goto error;
	319	}
	320	{
	321	ssize_t firing_policy_consumed_len;
	322	struct lttng_payload_view policy_view =
	323	lttng_payload_view_from_view(view, consumed_len,
	324	comm->firing_policy_len);
	325
	326	if (!lttng_payload_view_is_valid(&policy_view)) {
	327	ERR("Failed to create buffer view for firing policy.");
	328	goto error;
	329	}
	330
	331	firing_policy_consumed_len =
	332	lttng_firing_policy_create_from_payload(
	333	&policy_view, &policy);
	334	if (firing_policy_consumed_len < 0) {
	335	goto error;
	336	}
	337
	338	if (firing_policy_consumed_len != comm->firing_policy_len) {
	339	ERR("Failed to deserialize firing policy object: "
	340	"consumed-len: %zd, expected-len: %" PRIu32,
	341	firing_policy_consumed_len,
	342	comm->firing_policy_len);
	343	goto error;
	344	}
	345
	346	status = lttng_action_snapshot_session_set_firing_policy(
	347	action, policy);
	348	if (status != LTTNG_ACTION_STATUS_OK) {
	349	goto error;
	350	}
	351	}
	352
	353	variable_data += comm->firing_policy_len;
	354	consumed_len += comm->firing_policy_len;
	355
757c48a2 SM	356	*p_action = action;
	357	action = NULL;
	358
	359	goto end;
	360
	361	error:
	362	consumed_len = -1;
	363
	364	end:
d35c7a38	365	lttng_firing_policy_destroy(policy);
757c48a2 SM	366	lttng_action_snapshot_session_destroy(action);
	367	lttng_snapshot_output_destroy(snapshot_output);
	368
	369	return consumed_len;
	370	}
	371
	372	struct lttng_action *lttng_action_snapshot_session_create(void)
	373	{
d35c7a38 JR	374	struct lttng_action *action = NULL;
	375	struct lttng_firing_policy *policy = NULL;
	376	enum lttng_action_status status;
	377
	378	/* Create a every N = 1 firing policy. */
	379	policy = lttng_firing_policy_every_n_create(1);
	380	if (!policy) {
	381	goto end;
	382	}
757c48a2 SM	383
	384	action = zmalloc(sizeof(struct lttng_action_snapshot_session));
	385	if (!action) {
	386	goto end;
	387	}
	388
	389	lttng_action_init(action, LTTNG_ACTION_TYPE_SNAPSHOT_SESSION,
	390	lttng_action_snapshot_session_validate,
	391	lttng_action_snapshot_session_serialize,
	392	lttng_action_snapshot_session_is_equal,
	393	lttng_action_snapshot_session_destroy);
	394
d35c7a38 JR	395	status = lttng_action_snapshot_session_set_firing_policy(
	396	action, policy);
	397	if (status != LTTNG_ACTION_STATUS_OK) {
	398	free(action);
	399	action = NULL;
	400	goto end;
	401	}
	402
757c48a2	403	end:
d35c7a38	404	lttng_firing_policy_destroy(policy);
757c48a2 SM	405	return action;
	406	}
	407
	408	enum lttng_action_status lttng_action_snapshot_session_set_session_name(
	409	struct lttng_action action, const char session_name)
	410	{
	411	struct lttng_action_snapshot_session *action_snapshot_session;
	412	enum lttng_action_status status;
	413
	414	if (!action \|\| !IS_SNAPSHOT_SESSION_ACTION(action) \|\| !session_name \|\|
	415	strlen(session_name) == 0) {
	416	status = LTTNG_ACTION_STATUS_INVALID;
	417	goto end;
	418	}
	419
	420	action_snapshot_session = action_snapshot_session_from_action(action);
	421
	422	free(action_snapshot_session->session_name);
	423
	424	action_snapshot_session->session_name = strdup(session_name);
	425	if (!action_snapshot_session->session_name) {
	426	status = LTTNG_ACTION_STATUS_ERROR;
	427	goto end;
	428	}
	429
	430	status = LTTNG_ACTION_STATUS_OK;
	431	end:
	432	return status;
	433	}
	434
	435	enum lttng_action_status lttng_action_snapshot_session_get_session_name(
	436	const struct lttng_action action, const char *session_name)
	437	{
	438	const struct lttng_action_snapshot_session *action_snapshot_session;
	439	enum lttng_action_status status;
	440
	441	if (!action \|\| !IS_SNAPSHOT_SESSION_ACTION(action) \|\| !session_name) {
	442	status = LTTNG_ACTION_STATUS_INVALID;
	443	goto end;
	444	}
	445
	446	action_snapshot_session = action_snapshot_session_from_action_const(action);
	447
	448	if (action_snapshot_session->session_name) {
	449	*session_name = action_snapshot_session->session_name;
	450	status = LTTNG_ACTION_STATUS_OK;
	451	} else {
	452	status = LTTNG_ACTION_STATUS_UNSET;
	453	}
	454
	455	end:
	456
	457	return status;
	458	}
	459
	460	enum lttng_action_status lttng_action_snapshot_session_set_output(
	461	struct lttng_action *action,
	462	struct lttng_snapshot_output *output)
	463	{
	464	struct lttng_action_snapshot_session *action_snapshot_session;
	465	enum lttng_action_status status;
	466
	467	if (!action \|\| !IS_SNAPSHOT_SESSION_ACTION(action) \|\| !output) {
	468	status = LTTNG_ACTION_STATUS_INVALID;
469	goto end;
470	}
471
472	action_snapshot_session = action_snapshot_session_from_action(action);
473
474	lttng_snapshot_output_destroy(action_snapshot_session->output);
475	action_snapshot_session->output = output;
476
477	status = LTTNG_ACTION_STATUS_OK;
478
479	end:
480	return status;
481	}
482
483	enum lttng_action_status lttng_action_snapshot_session_get_output(
484	const struct lttng_action *action,
485	const struct lttng_snapshot_output **output)
486	{
487	const struct lttng_action_snapshot_session *action_snapshot_session;
488	enum lttng_action_status status;
489
490	if (!action \|\| !IS_SNAPSHOT_SESSION_ACTION(action)\|\| !output) {
491	status = LTTNG_ACTION_STATUS_INVALID;
492	goto end;
493	}
494
495	action_snapshot_session = action_snapshot_session_from_action_const(action);
496
497	if (action_snapshot_session->output) {
498	*output = action_snapshot_session->output;
499	status = LTTNG_ACTION_STATUS_OK;
500	} else {
501	status = LTTNG_ACTION_STATUS_UNSET;
502	}
503
504	end:
505	return status;
506	}
d35c7a38 JR	507
	508	enum lttng_action_status lttng_action_snapshot_session_set_firing_policy(
	509	struct lttng_action *action,
	510	const struct lttng_firing_policy *policy)
	511	{
	512	enum lttng_action_status status;
	513	struct lttng_action_snapshot_session *snapshot_session_action;
	514	struct lttng_firing_policy *copy = NULL;
	515
	516	if (!action \|\| !policy \|\| !IS_SNAPSHOT_SESSION_ACTION(action)) {
	517	status = LTTNG_ACTION_STATUS_INVALID;
	518	goto end;
	519	}
	520
	521	copy = lttng_firing_policy_copy(policy);
	522	if (!copy) {
	523	status = LTTNG_ACTION_STATUS_ERROR;
	524	goto end;
	525	}
	526
	527	snapshot_session_action = action_snapshot_session_from_action(action);
	528
	529	/* Free the previous firing policy .*/
	530	lttng_firing_policy_destroy(snapshot_session_action->policy);
	531
	532	/* Assign the policy. */
	533	snapshot_session_action->policy = copy;
	534	status = LTTNG_ACTION_STATUS_OK;
	535	copy = NULL;
	536
	537	end:
	538	lttng_firing_policy_destroy(copy);
	539	return status;
	540	}
	541
	542	enum lttng_action_status lttng_action_snapshot_session_get_firing_policy(
	543	const struct lttng_action *action,
	544	const struct lttng_firing_policy **policy)
	545	{
	546	enum lttng_action_status status;
	547	const struct lttng_action_snapshot_session *snapshot_session_action;
	548
	549	if (!action \|\| !policy \|\| !IS_SNAPSHOT_SESSION_ACTION(action)) {
	550	status = LTTNG_ACTION_STATUS_INVALID;
	551	goto end;
	552	}
	553
	554	snapshot_session_action =
	555	action_snapshot_session_from_action_const(action);
	556
	557	*policy = snapshot_session_action->policy;
	558	status = LTTNG_ACTION_STATUS_OK;
	559	end:
	560	return status;
	561	}