Fix: report error to client on consumerd error

[lttng-tools.git] / src / common / consumer.h

diff --git a/src/common/consumer.h b/src/common/consumer.h
index dc5fc9968be02fbf45b223ef20a8371fdc4e0005..6ac781605c7284ecf7319e2b10fa0c3920b441b3 100644 (file)
--- a/src/common/consumer.h
+++ b/src/common/consumer.h
@@ -2,19 +2,18 @@
  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
  * Copyright (C) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; only version 2
- * of the License.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2 only,
+ * as published by the Free Software Foundation.
  *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
  *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
 #ifndef _LTTNG_CONSUMER_H
@@ -26,7 +25,8 @@
 
 #include <lttng/lttng.h>
 
-#include "src/common/hashtable/hashtable.h"
+#include <common/hashtable/hashtable.h>
+#include <common/compat/fcntl.h>
 
 /*
  * When the receiving thread dies, we need to have a way to make the polling
@@ -113,6 +113,7 @@ struct lttng_consumer_stream {
        /* For UST */
        struct lttng_ust_lib_ring_buffer *buf;
        int cpu;
+       int data_read;
        int hangup_flush_done;
        /* UID/GID of the user owning the session to which stream belongs */
        uid_t uid;
@@ -124,8 +125,11 @@ struct lttng_consumer_stream {
  * process.
  */
 struct lttng_consumer_local_data {
-       /* function to call when data is available on a buffer */
-       int (*on_buffer_ready)(struct lttng_consumer_stream *stream,
+       /*
+        * Function to call when data is available on a buffer.
+        * Returns the number of bytes read, or negative error value.
+        */
+       ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
                        struct lttng_consumer_local_data *ctx);
        /*
         * function to call when we receive a new channel, it receives a
@@ -284,16 +288,16 @@ int consumer_add_channel(struct lttng_consumer_channel *channel);
 
 extern struct lttng_consumer_local_data *lttng_consumer_create(
                enum lttng_consumer_type type,
-               int (*buffer_ready)(struct lttng_consumer_stream *stream,
+               ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
                        struct lttng_consumer_local_data *ctx),
                int (*recv_channel)(struct lttng_consumer_channel *channel),
                int (*recv_stream)(struct lttng_consumer_stream *stream),
                int (*update_stream)(int sessiond_key, uint32_t state));
 extern void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
-extern int lttng_consumer_on_read_subbuffer_mmap(
+extern ssize_t lttng_consumer_on_read_subbuffer_mmap(
                struct lttng_consumer_local_data *ctx,
                struct lttng_consumer_stream *stream, unsigned long len);
-extern int lttng_consumer_on_read_subbuffer_splice(
+extern ssize_t lttng_consumer_on_read_subbuffer_splice(
                struct lttng_consumer_local_data *ctx,
                struct lttng_consumer_stream *stream, unsigned long len);
 extern int lttng_consumer_take_snapshot(struct lttng_consumer_local_data *ctx,
@@ -307,7 +311,7 @@ extern void *lttng_consumer_thread_receive_fds(void *data);
 extern int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                int sock, struct pollfd *consumer_sockpoll);
 
-int lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
+ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
                struct lttng_consumer_local_data *ctx);
 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);