X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust-ctl%2Fustctl.c;h=c22f578536e873873a1b813efe8b311d39d74e29;hb=1584cac2fb5dea4531f529b73a62eaccb95da897;hp=aed40f26382ac94f4ad38ec26cea3a350774e9be;hpb=74d81a6cca2cd4a7718bba9368f382f9f2fbba84;p=lttng-ust.git

diff --git a/liblttng-ust-ctl/ustctl.c b/liblttng-ust-ctl/ustctl.c
index aed40f26..c22f5785 100644
--- a/liblttng-ust-ctl/ustctl.c
+++ b/liblttng-ust-ctl/ustctl.c
@@ -22,6 +22,7 @@
 #include <lttng/ust-abi.h>
 #include <lttng/ust-events.h>
 #include <sys/mman.h>
+#include <byteswap.h>
 
 #include <usterr-signal-safe.h>
 #include <ust-comm.h>
@@ -29,6 +30,13 @@
 
 #include "../libringbuffer/backend.h"
 #include "../libringbuffer/frontend.h"
+#include "../liblttng-ust/wait.h"
+
+/*
+ * Number of milliseconds to retry before failing metadata writes on
+ * buffer full condition. (10 seconds)
+ */
+#define LTTNG_METADATA_TIMEOUT_MSEC	10000
 
 /*
  * Channel representation within consumer.
@@ -38,6 +46,8 @@ struct ustctl_consumer_channel {
 
 	/* initial attributes */
 	struct ustctl_consumer_channel_attr attr;
+	int wait_fd;				/* monitor close() */
+	int wakeup_fd;				/* monitor close() */
 };
 
 /*
@@ -53,10 +63,14 @@ struct ustctl_consumer_stream {
 };
 
 extern void lttng_ring_buffer_client_overwrite_init(void);
+extern void lttng_ring_buffer_client_overwrite_rt_init(void);
 extern void lttng_ring_buffer_client_discard_init(void);
+extern void lttng_ring_buffer_client_discard_rt_init(void);
 extern void lttng_ring_buffer_metadata_client_init(void);
 extern void lttng_ring_buffer_client_overwrite_exit(void);
+extern void lttng_ring_buffer_client_overwrite_rt_exit(void);
 extern void lttng_ring_buffer_client_discard_exit(void);
+extern void lttng_ring_buffer_client_discard_rt_exit(void);
 extern void lttng_ring_buffer_metadata_client_exit(void);
 
 volatile enum ust_loglevel ust_loglevel;
@@ -87,6 +101,13 @@ int ustctl_release_object(int sock, struct lttng_ust_object_data *data)
 
 	switch (data->type) {
 	case LTTNG_UST_OBJECT_TYPE_CHANNEL:
+		if (data->u.channel.wakeup_fd >= 0) {
+			ret = close(data->u.channel.wakeup_fd);
+			if (ret < 0) {
+				ret = -errno;
+				return ret;
+			}
+		}
 		free(data->u.channel.data);
 		break;
 	case LTTNG_UST_OBJECT_TYPE_STREAM:
@@ -105,6 +126,9 @@ int ustctl_release_object(int sock, struct lttng_ust_object_data *data)
 			}
 		}
 		break;
+	case LTTNG_UST_OBJECT_TYPE_EVENT:
+	case LTTNG_UST_OBJECT_TYPE_CONTEXT:
+		break;
 	default:
 		assert(0);
 	}
@@ -166,6 +190,7 @@ int ustctl_create_event(int sock, struct lttng_ust_event *ev,
 	event_data = zmalloc(sizeof(*event_data));
 	if (!event_data)
 		return -ENOMEM;
+	event_data->type = LTTNG_UST_OBJECT_TYPE_EVENT;
 	memset(&lum, 0, sizeof(lum));
 	lum.handle = channel_data->handle;
 	lum.cmd = LTTNG_UST_EVENT;
@@ -200,6 +225,7 @@ int ustctl_add_context(int sock, struct lttng_ust_context *ctx,
 	context_data = zmalloc(sizeof(*context_data));
 	if (!context_data)
 		return -ENOMEM;
+	context_data->type = LTTNG_UST_OBJECT_TYPE_CONTEXT;
 	memset(&lum, 0, sizeof(lum));
 	lum.handle = obj_data->handle;
 	lum.cmd = LTTNG_UST_CONTEXT;
@@ -209,8 +235,8 @@ int ustctl_add_context(int sock, struct lttng_ust_context *ctx,
 		free(context_data);
 		return ret;
 	}
-	context_data->handle = lur.ret_val;
-	DBG("received context handle %u", context_data->handle);
+	context_data->handle = -1;
+	DBG("Context created successfully");
 	*_context_data = context_data;
 	return ret;
 }
@@ -239,8 +265,6 @@ int ustctl_set_filter(int sock, struct lttng_ust_filter_bytecode *bytecode,
 	ret = ustcomm_send_unix_sock(sock, bytecode->data,
 				bytecode->len);
 	if (ret < 0) {
-		if (ret == -ECONNRESET)
-			fprintf(stderr, "remote end closed connection\n");
 		return ret;
 	}
 	if (ret != bytecode->len)
@@ -458,6 +482,7 @@ int ustctl_send_channel(int sock,
 		enum lttng_ust_chan_type type,
 		void *data,
 		uint64_t size,
+		int wakeup_fd,
 		int send_fd_only)
 {
 	ssize_t len;
@@ -491,6 +516,14 @@ int ustctl_send_channel(int sock,
 			return -EIO;
 	}
 
+	/* Send wakeup fd */
+	len = ustcomm_send_fds_unix_sock(sock, &wakeup_fd, 1);
+	if (len <= 0) {
+		if (len < 0)
+			return len;
+		else
+			return -EIO;
+	}
 	return 0;
 }
 
@@ -558,6 +591,7 @@ int ustctl_recv_channel_from_consumer(int sock,
 {
 	struct lttng_ust_object_data *channel_data;
 	ssize_t len;
+	int wakeup_fd;
 	int ret;
 
 	channel_data = zmalloc(sizeof(*channel_data));
@@ -566,6 +600,7 @@ int ustctl_recv_channel_from_consumer(int sock,
 		goto error_alloc;
 	}
 	channel_data->type = LTTNG_UST_OBJECT_TYPE_CHANNEL;
+	channel_data->handle = -1;
 
 	/* recv mmap size */
 	len = ustcomm_recv_unix_sock(sock, &channel_data->size,
@@ -604,7 +639,18 @@ int ustctl_recv_channel_from_consumer(int sock,
 			ret = -EINVAL;
 		goto error_recv_data;
 	}
-
+	/* recv wakeup fd */
+	len = ustcomm_recv_fds_unix_sock(sock, &wakeup_fd, 1);
+	if (len <= 0) {
+		if (len < 0) {
+			ret = len;
+			goto error_recv_data;
+		} else {
+			ret = -EIO;
+			goto error_recv_data;
+		}
+	}
+	channel_data->u.channel.wakeup_fd = wakeup_fd;
 	*_channel_data = channel_data;
 	return 0;
 
@@ -704,14 +750,13 @@ int ustctl_send_channel_to_ust(int sock, int session_handle,
 			channel_data->u.channel.type,
 			channel_data->u.channel.data,
 			channel_data->size,
+			channel_data->u.channel.wakeup_fd,
 			1);
 	if (ret)
 		return ret;
 	ret = ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 	if (!ret) {
-		if (lur.ret_val >= 0) {
-			channel_data->handle = lur.ret_val;
-		}
+		channel_data->handle = lur.ret_val;
 	}
 	return ret;
 }
@@ -746,6 +791,119 @@ int ustctl_send_stream_to_ust(int sock,
 	return ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
 }
 
+int ustctl_duplicate_ust_object_data(struct lttng_ust_object_data **dest,
+                struct lttng_ust_object_data *src)
+{
+	struct lttng_ust_object_data *obj;
+	int ret;
+
+	if (src->handle != -1) {
+		ret = -EINVAL;
+		goto error;
+	}
+
+	obj = zmalloc(sizeof(*obj));
+	if (!obj) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	obj->type = src->type;
+	obj->handle = src->handle;
+	obj->size = src->size;
+
+	switch (obj->type) {
+	case LTTNG_UST_OBJECT_TYPE_CHANNEL:
+	{
+		obj->u.channel.type = src->u.channel.type;
+		if (src->u.channel.wakeup_fd >= 0) {
+			obj->u.channel.wakeup_fd =
+				dup(src->u.channel.wakeup_fd);
+			if (obj->u.channel.wakeup_fd < 0) {
+				ret = errno;
+				goto chan_error_wakeup_fd;
+			}
+		} else {
+			obj->u.channel.wakeup_fd =
+				src->u.channel.wakeup_fd;
+		}
+		obj->u.channel.data = zmalloc(obj->size);
+		if (!obj->u.channel.data) {
+			ret = -ENOMEM;
+			goto chan_error_alloc;
+		}
+		memcpy(obj->u.channel.data, src->u.channel.data, obj->size);
+		break;
+
+	chan_error_alloc:
+		if (src->u.channel.wakeup_fd >= 0) {
+			int closeret;
+
+			closeret = close(obj->u.channel.wakeup_fd);
+			if (closeret) {
+				PERROR("close");
+			}
+		}
+	chan_error_wakeup_fd:
+		goto error_type;
+
+	}
+
+	case LTTNG_UST_OBJECT_TYPE_STREAM:
+	{
+		obj->u.stream.stream_nr = src->u.stream.stream_nr;
+		if (src->u.stream.wakeup_fd >= 0) {
+			obj->u.stream.wakeup_fd =
+				dup(src->u.stream.wakeup_fd);
+			if (obj->u.stream.wakeup_fd < 0) {
+				ret = errno;
+				goto stream_error_wakeup_fd;
+			}
+		} else {
+			obj->u.stream.wakeup_fd =
+				src->u.stream.wakeup_fd;
+		}
+
+		if (src->u.stream.shm_fd >= 0) {
+			obj->u.stream.shm_fd =
+				dup(src->u.stream.shm_fd);
+			if (obj->u.stream.shm_fd < 0) {
+				ret = errno;
+				goto stream_error_shm_fd;
+			}
+		} else {
+			obj->u.stream.shm_fd =
+				src->u.stream.shm_fd;
+		}
+		break;
+
+	stream_error_shm_fd:
+		if (src->u.stream.wakeup_fd >= 0) {
+			int closeret;
+
+			closeret = close(obj->u.stream.wakeup_fd);
+			if (closeret) {
+				PERROR("close");
+			}
+		}
+	stream_error_wakeup_fd:
+		goto error_type;
+	}
+
+	default:
+		ret = -EINVAL;
+		goto error_type;
+	}
+
+	*dest = obj;
+	return 0;
+
+error_type:
+	free(obj);
+error:
+	return ret;
+}
+
 
 /* Buffer operations */
 
@@ -759,8 +917,19 @@ struct ustctl_consumer_channel *
 	switch (attr->type) {
 	case LTTNG_UST_CHAN_PER_CPU:
 		if (attr->output == LTTNG_UST_MMAP) {
-			transport_name = attr->overwrite ?
-				"relay-overwrite-mmap" : "relay-discard-mmap";
+			if (attr->overwrite) {
+				if (attr->read_timer_interval == 0) {
+					transport_name = "relay-overwrite-mmap";
+				} else {
+					transport_name = "relay-overwrite-rt-mmap";
+				}
+			} else {
+				if (attr->read_timer_interval == 0) {
+					transport_name = "relay-discard-mmap";
+				} else {
+					transport_name = "relay-discard-rt-mmap";
+				}
+			}
 		} else {
 			return NULL;
 		}
@@ -779,7 +948,7 @@ struct ustctl_consumer_channel *
 	transport = lttng_transport_find(transport_name);
 	if (!transport) {
 		DBG("LTTng transport %s not found\n",
-		       transport_name);
+			transport_name);
 		return NULL;
 	}
 
@@ -788,15 +957,17 @@ struct ustctl_consumer_channel *
 		return NULL;
 
 	chan->chan = transport->ops.channel_create(transport_name, NULL,
-                        attr->subbuf_size, attr->num_subbuf,
+			attr->subbuf_size, attr->num_subbuf,
 			attr->switch_timer_interval,
-                        attr->read_timer_interval,
-			attr->uuid);
+			attr->read_timer_interval,
+			attr->uuid, attr->chan_id);
 	if (!chan->chan) {
 		goto chan_error;
 	}
 	chan->chan->ops = &transport->ops;
 	memcpy(&chan->attr, attr, sizeof(chan->attr));
+	chan->wait_fd = ustctl_channel_get_wait_fd(chan);
+	chan->wakeup_fd = ustctl_channel_get_wakeup_fd(chan);
 	return chan;
 
 chan_error:
@@ -806,6 +977,8 @@ chan_error:
 
 void ustctl_destroy_channel(struct ustctl_consumer_channel *chan)
 {
+	(void) ustctl_channel_close_wait_fd(chan);
+	(void) ustctl_channel_close_wakeup_fd(chan);
 	chan->chan->ops->channel_destroy(chan->chan);
 	free(chan);
 }
@@ -822,6 +995,7 @@ int ustctl_send_channel_to_sessiond(int sock,
 			channel->attr.type,
 			table->objects[0].memory_map,
 			table->objects[0].memory_map_size,
+			channel->wakeup_fd,
 			0);
 }
 
@@ -838,12 +1012,82 @@ int ustctl_send_stream_to_sessiond(int sock,
 			0);
 }
 
+int ustctl_write_metadata_to_channel(
+		struct ustctl_consumer_channel *channel,
+		const char *metadata_str,	/* NOT null-terminated */
+		size_t len)			/* metadata length */
+{
+	struct lttng_ust_lib_ring_buffer_ctx ctx;
+	struct lttng_channel *chan = channel->chan;
+	const char *str = metadata_str;
+	int ret = 0, waitret;
+	size_t reserve_len, pos;
+
+	for (pos = 0; pos < len; pos += reserve_len) {
+		reserve_len = min_t(size_t,
+				chan->ops->packet_avail_size(chan->chan, chan->handle),
+				len - pos);
+		lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len,
+					 sizeof(char), -1, chan->handle);
+		/*
+		 * We don't care about metadata buffer's records lost
+		 * count, because we always retry here. Report error if
+		 * we need to bail out after timeout or being
+		 * interrupted.
+		 */
+		waitret = wait_cond_interruptible_timeout(
+			({
+				ret = chan->ops->event_reserve(&ctx, 0);
+				ret != -ENOBUFS || !ret;
+			}),
+			LTTNG_METADATA_TIMEOUT_MSEC);
+		if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) {
+			DBG("LTTng: Failure to write metadata to buffers (%s)\n",
+				waitret == -EINTR ? "interrupted" :
+					(ret == -ENOBUFS ? "timeout" : "I/O error"));
+			if (waitret == -EINTR)
+				ret = waitret;
+			goto end;
+		}
+		chan->ops->event_write(&ctx, &str[pos], reserve_len);
+		chan->ops->event_commit(&ctx);
+	}
+end:
+	return ret;
+}
+
+int ustctl_channel_close_wait_fd(struct ustctl_consumer_channel *consumer_chan)
+{
+	struct channel *chan;
+	int ret;
+
+	chan = consumer_chan->chan->chan;
+	ret = ring_buffer_channel_close_wait_fd(&chan->backend.config,
+			chan, chan->handle);
+	if (!ret)
+		consumer_chan->wait_fd = -1;
+	return ret;
+}
+
+int ustctl_channel_close_wakeup_fd(struct ustctl_consumer_channel *consumer_chan)
+{
+	struct channel *chan;
+	int ret;
+
+	chan = consumer_chan->chan->chan;
+	ret = ring_buffer_channel_close_wakeup_fd(&chan->backend.config,
+			chan, chan->handle);
+	if (!ret)
+		consumer_chan->wakeup_fd = -1;
+	return ret;
+}
+
 int ustctl_stream_close_wait_fd(struct ustctl_consumer_stream *stream)
 {
 	struct channel *chan;
 
 	chan = stream->chan->chan->chan;
-	return ring_buffer_close_wait_fd(&chan->backend.config,
+	return ring_buffer_stream_close_wait_fd(&chan->backend.config,
 			chan, stream->handle, stream->cpu);
 }
 
@@ -852,7 +1096,7 @@ int ustctl_stream_close_wakeup_fd(struct ustctl_consumer_stream *stream)
 	struct channel *chan;
 
 	chan = stream->chan->chan->chan;
-	return ring_buffer_close_wakeup_fd(&chan->backend.config,
+	return ring_buffer_stream_close_wakeup_fd(&chan->backend.config,
 			chan, stream->handle, stream->cpu);
 }
 
@@ -909,11 +1153,29 @@ void ustctl_destroy_stream(struct ustctl_consumer_stream *stream)
 	assert(stream);
 	buf = stream->buf;
 	consumer_chan = stream->chan;
+	(void) ustctl_stream_close_wait_fd(stream);
+	(void) ustctl_stream_close_wakeup_fd(stream);
 	lib_ring_buffer_release_read(buf, consumer_chan->chan->handle);
 	free(stream);
 }
 
-int ustctl_get_wait_fd(struct ustctl_consumer_stream *stream)
+int ustctl_channel_get_wait_fd(struct ustctl_consumer_channel *chan)
+{
+	if (!chan)
+		return -EINVAL;
+	return shm_get_wait_fd(chan->chan->handle,
+		&chan->chan->handle->chan._ref);
+}
+
+int ustctl_channel_get_wakeup_fd(struct ustctl_consumer_channel *chan)
+{
+	if (!chan)
+		return -EINVAL;
+	return shm_get_wakeup_fd(chan->chan->handle,
+		&chan->chan->handle->chan._ref);
+}
+
+int ustctl_stream_get_wait_fd(struct ustctl_consumer_stream *stream)
 {
 	struct lttng_ust_lib_ring_buffer *buf;
 	struct ustctl_consumer_channel *consumer_chan;
@@ -925,7 +1187,7 @@ int ustctl_get_wait_fd(struct ustctl_consumer_stream *stream)
 	return shm_get_wait_fd(consumer_chan->chan->handle, &buf->self._ref);
 }
 
-int ustctl_get_wakeup_fd(struct ustctl_consumer_stream *stream)
+int ustctl_stream_get_wakeup_fd(struct ustctl_consumer_stream *stream)
 {
 	struct lttng_ust_lib_ring_buffer *buf;
 	struct ustctl_consumer_channel *consumer_chan;
@@ -1011,7 +1273,7 @@ int ustctl_get_mmap_read_offset(struct ustctl_consumer_stream *stream,
 	if (chan->backend.config.output != RING_BUFFER_MMAP)
 		return -EINVAL;
 	sb_bindex = subbuffer_id_get_index(&chan->backend.config,
-					   buf->backend.buf_rsb.id);
+					buf->backend.buf_rsb.id);
 	*off = shmp(consumer_chan->chan->handle,
 		shmp_index(consumer_chan->chan->handle, buf->backend.array, sb_bindex)->shmp)->mmap_offset;
 	return 0;
@@ -1169,19 +1431,362 @@ void ustctl_flush_buffer(struct ustctl_consumer_stream *stream,
 		consumer_chan->chan->handle);
 }
 
+/*
+ * Returns 0 on success, negative error value on error.
+ */
+int ustctl_recv_reg_msg(int sock,
+	enum ustctl_socket_type *type,
+	uint32_t *major,
+	uint32_t *minor,
+	uint32_t *pid,
+	uint32_t *ppid,
+	uint32_t *uid,
+	uint32_t *gid,
+	uint32_t *bits_per_long,
+	uint32_t *uint8_t_alignment,
+	uint32_t *uint16_t_alignment,
+	uint32_t *uint32_t_alignment,
+	uint32_t *uint64_t_alignment,
+	uint32_t *long_alignment,
+	int *byte_order,
+	char *name)
+{
+	ssize_t len;
+	struct ustctl_reg_msg reg_msg;
+
+	len = ustcomm_recv_unix_sock(sock, &reg_msg, sizeof(reg_msg));
+	if (len > 0 && len != sizeof(reg_msg))
+		return -EIO;
+	if (len == 0)
+		return -EPIPE;
+	if (len < 0)
+		return len;
+
+	if (reg_msg.magic == LTTNG_UST_COMM_MAGIC) {
+		*byte_order = BYTE_ORDER == BIG_ENDIAN ?
+				BIG_ENDIAN : LITTLE_ENDIAN;
+	} else if (reg_msg.magic == bswap_32(LTTNG_UST_COMM_MAGIC)) {
+		*byte_order = BYTE_ORDER == BIG_ENDIAN ?
+				LITTLE_ENDIAN : BIG_ENDIAN;
+	} else {
+		return -LTTNG_UST_ERR_INVAL_MAGIC;
+	}
+	switch (reg_msg.socket_type) {
+	case 0:	*type = USTCTL_SOCKET_CMD;
+		break;
+	case 1:	*type = USTCTL_SOCKET_NOTIFY;
+		break;
+	default:
+		return -LTTNG_UST_ERR_INVAL_SOCKET_TYPE;
+	}
+	*major = reg_msg.major;
+	*minor = reg_msg.minor;
+	*pid = reg_msg.pid;
+	*ppid = reg_msg.ppid;
+	*uid = reg_msg.uid;
+	*gid = reg_msg.gid;
+	*bits_per_long = reg_msg.bits_per_long;
+	*uint8_t_alignment = reg_msg.uint8_t_alignment;
+	*uint16_t_alignment = reg_msg.uint16_t_alignment;
+	*uint32_t_alignment = reg_msg.uint32_t_alignment;
+	*uint64_t_alignment = reg_msg.uint64_t_alignment;
+	*long_alignment = reg_msg.long_alignment;
+	memcpy(name, reg_msg.name, LTTNG_UST_ABI_PROCNAME_LEN);
+	if (reg_msg.major != LTTNG_UST_ABI_MAJOR_VERSION) {
+		return -LTTNG_UST_ERR_UNSUP_MAJOR;
+	}
+
+	return 0;
+}
+
+int ustctl_recv_notify(int sock, enum ustctl_notify_cmd *notify_cmd)
+{
+	struct ustcomm_notify_hdr header;
+	ssize_t len;
+
+	len = ustcomm_recv_unix_sock(sock, &header, sizeof(header));
+	if (len > 0 && len != sizeof(header))
+		return -EIO;
+	if (len == 0)
+		return -EPIPE;
+	if (len < 0)
+		return len;
+	switch (header.notify_cmd) {
+	case 0:
+		*notify_cmd = USTCTL_NOTIFY_CMD_EVENT;
+		break;
+	case 1:
+		*notify_cmd = USTCTL_NOTIFY_CMD_CHANNEL;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/*
+ * Returns 0 on success, negative error value on error.
+ */
+int ustctl_recv_register_event(int sock,
+	int *session_objd,
+	int *channel_objd,
+	char *event_name,
+	int *loglevel,
+	char **signature,
+	size_t *nr_fields,
+	struct ustctl_field **fields,
+	char **model_emf_uri)
+{
+	ssize_t len;
+	struct ustcomm_notify_event_msg msg;
+	size_t signature_len, fields_len, model_emf_uri_len;
+	char *a_sign = NULL, *a_model_emf_uri = NULL;
+	struct ustctl_field *a_fields = NULL;
+
+	len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
+	if (len > 0 && len != sizeof(msg))
+		return -EIO;
+	if (len == 0)
+		return -EPIPE;
+	if (len < 0)
+		return len;
+
+	*session_objd = msg.session_objd;
+	*channel_objd = msg.channel_objd;
+	strncpy(event_name, msg.event_name, LTTNG_UST_SYM_NAME_LEN);
+	event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
+	*loglevel = msg.loglevel;
+	signature_len = msg.signature_len;
+	fields_len = msg.fields_len;
+
+	if (fields_len % sizeof(*a_fields) != 0) {
+		return -EINVAL;
+	}
+
+	model_emf_uri_len = msg.model_emf_uri_len;
+
+	/* recv signature. contains at least \0. */
+	a_sign = zmalloc(signature_len);
+	if (!a_sign)
+		return -ENOMEM;
+	len = ustcomm_recv_unix_sock(sock, a_sign, signature_len);
+	if (len > 0 && len != signature_len) {
+		len = -EIO;
+		goto signature_error;
+	}
+	if (len == 0) {
+		len = -EPIPE;
+		goto signature_error;
+	}
+	if (len < 0) {
+		goto signature_error;
+	}
+	/* Enforce end of string */
+	a_sign[signature_len - 1] = '\0';
+
+	/* recv fields */
+	if (fields_len) {
+		a_fields = zmalloc(fields_len);
+		if (!a_fields) {
+			len = -ENOMEM;
+			goto signature_error;
+		}
+		len = ustcomm_recv_unix_sock(sock, a_fields, fields_len);
+		if (len > 0 && len != fields_len) {
+			len = -EIO;
+			goto fields_error;
+		}
+		if (len == 0) {
+			len = -EPIPE;
+			goto fields_error;
+		}
+		if (len < 0) {
+			goto fields_error;
+		}
+	}
+
+	if (model_emf_uri_len) {
+		/* recv model_emf_uri_len */
+		a_model_emf_uri = zmalloc(model_emf_uri_len);
+		if (!a_model_emf_uri) {
+			len = -ENOMEM;
+			goto fields_error;
+		}
+		len = ustcomm_recv_unix_sock(sock, a_model_emf_uri,
+				model_emf_uri_len);
+		if (len > 0 && len != model_emf_uri_len) {
+			len = -EIO;
+			goto model_error;
+		}
+		if (len == 0) {
+			len = -EPIPE;
+			goto model_error;
+		}
+		if (len < 0) {
+			goto model_error;
+		}
+		/* Enforce end of string */
+		a_model_emf_uri[model_emf_uri_len - 1] = '\0';
+	}
+
+	*signature = a_sign;
+	*nr_fields = fields_len / sizeof(*a_fields);
+	*fields = a_fields;
+	*model_emf_uri = a_model_emf_uri;
+
+	return 0;
+
+model_error:
+	free(a_model_emf_uri);
+fields_error:
+	free(a_fields);
+signature_error:
+	free(a_sign);
+	return len;
+}
+
+/*
+ * Returns 0 on success, negative error value on error.
+ */
+int ustctl_reply_register_event(int sock,
+	uint32_t id,
+	int ret_code)
+{
+	ssize_t len;
+	struct {
+		struct ustcomm_notify_hdr header;
+		struct ustcomm_notify_event_reply r;
+	} reply;
+
+	memset(&reply, 0, sizeof(reply));
+	reply.header.notify_cmd = USTCTL_NOTIFY_CMD_EVENT;
+	reply.r.ret_code = ret_code;
+	reply.r.event_id = id;
+	len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
+	if (len > 0 && len != sizeof(reply))
+		return -EIO;
+	if (len < 0)
+		return len;
+	return 0;
+}
+
+/*
+ * Returns 0 on success, negative UST or system error value on error.
+ */
+int ustctl_recv_register_channel(int sock,
+	int *session_objd,		/* session descriptor (output) */
+	int *channel_objd,		/* channel descriptor (output) */
+	size_t *nr_fields,
+	struct ustctl_field **fields)
+{
+	ssize_t len;
+	struct ustcomm_notify_channel_msg msg;
+	size_t fields_len;
+	struct ustctl_field *a_fields;
+
+	len = ustcomm_recv_unix_sock(sock, &msg, sizeof(msg));
+	if (len > 0 && len != sizeof(msg))
+		return -EIO;
+	if (len == 0)
+		return -EPIPE;
+	if (len < 0)
+		return len;
+
+	*session_objd = msg.session_objd;
+	*channel_objd = msg.channel_objd;
+	fields_len = msg.ctx_fields_len;
+
+	if (fields_len % sizeof(*a_fields) != 0) {
+		return -EINVAL;
+	}
+
+	/* recv fields */
+	if (fields_len) {
+		a_fields = zmalloc(fields_len);
+		if (!a_fields) {
+			len = -ENOMEM;
+			goto alloc_error;
+		}
+		len = ustcomm_recv_unix_sock(sock, a_fields, fields_len);
+		if (len > 0 && len != fields_len) {
+			len = -EIO;
+			goto fields_error;
+		}
+		if (len == 0) {
+			len = -EPIPE;
+			goto fields_error;
+		}
+		if (len < 0) {
+			goto fields_error;
+		}
+		*fields = a_fields;
+	} else {
+		*fields = NULL;
+	}
+	*nr_fields = fields_len / sizeof(*a_fields);
+	return 0;
+
+fields_error:
+	free(a_fields);
+alloc_error:
+	return len;
+}
+
+/*
+ * Returns 0 on success, negative error value on error.
+ */
+int ustctl_reply_register_channel(int sock,
+	uint32_t chan_id,
+	enum ustctl_channel_header header_type,
+	int ret_code)
+{
+	ssize_t len;
+	struct {
+		struct ustcomm_notify_hdr header;
+		struct ustcomm_notify_channel_reply r;
+	} reply;
+
+	memset(&reply, 0, sizeof(reply));
+	reply.header.notify_cmd = USTCTL_NOTIFY_CMD_CHANNEL;
+	reply.r.ret_code = ret_code;
+	reply.r.chan_id = chan_id;
+	switch (header_type) {
+	case USTCTL_CHANNEL_HEADER_COMPACT:
+		reply.r.header_type = 1;
+		break;
+	case USTCTL_CHANNEL_HEADER_LARGE:
+		reply.r.header_type = 2;
+		break;
+	default:
+		reply.r.header_type = 0;
+		break;
+	}
+	len = ustcomm_send_unix_sock(sock, &reply, sizeof(reply));
+	if (len > 0 && len != sizeof(reply))
+		return -EIO;
+	if (len < 0)
+		return len;
+	return 0;
+}
+
 static __attribute__((constructor))
 void ustctl_init(void)
 {
 	init_usterr();
 	lttng_ring_buffer_metadata_client_init();
 	lttng_ring_buffer_client_overwrite_init();
+	lttng_ring_buffer_client_overwrite_rt_init();
 	lttng_ring_buffer_client_discard_init();
+	lttng_ring_buffer_client_discard_rt_init();
+	lib_ringbuffer_signal_init();
 }
 
 static __attribute__((destructor))
 void ustctl_exit(void)
 {
+	lttng_ring_buffer_client_discard_rt_exit();
 	lttng_ring_buffer_client_discard_exit();
+	lttng_ring_buffer_client_overwrite_rt_exit();
 	lttng_ring_buffer_client_overwrite_exit();
 	lttng_ring_buffer_metadata_client_exit();
 }