From 12f3dabc3d0381bda42b425af136b445177600bf Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Wed, 6 Mar 2013 18:18:59 -0500
Subject: [PATCH] Implement ustctl_duplicate_ust_object_data

Allow sessiond to duplicate its object data. Useful for per-uid buffers.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---
 include/lttng/ust-ctl.h   |   8 +++
 liblttng-ust-ctl/ustctl.c | 114 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 122 insertions(+)

diff --git a/include/lttng/ust-ctl.h b/include/lttng/ust-ctl.h
index ed2b513d..2cf537a3 100644
--- a/include/lttng/ust-ctl.h
+++ b/include/lttng/ust-ctl.h
@@ -128,6 +128,14 @@ int ustctl_send_stream_to_ust(int sock,
 		struct lttng_ust_object_data *channel_data,
 		struct lttng_ust_object_data *stream_data);
 
+/*
+ * ustctl_duplicate_ust_object_data allocated a new object in "dest" if
+ * it succeeds (returns 0). It must be released using
+ * ustctl_release_object() and then freed with free().
+ */
+int ustctl_duplicate_ust_object_data(struct lttng_ust_object_data **dest,
+		struct lttng_ust_object_data *src);
+
 /*
  * API used by consumer.
  */
diff --git a/liblttng-ust-ctl/ustctl.c b/liblttng-ust-ctl/ustctl.c
index 641c508b..e00caf15 100644
--- a/liblttng-ust-ctl/ustctl.c
+++ b/liblttng-ust-ctl/ustctl.c
@@ -596,6 +596,7 @@ 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,
@@ -788,6 +789,119 @@ 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 */
 
-- 
2.34.1