SoW-2020-0002: Trace Hit Counters

[lttng-ust.git] / liblttng-ust / lttng-ust-comm.c

diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
index f45097b030116fc9a17958d74803adcdc8a8d867..0cd0d178c624fdef3f058583295226d93cdc18df 100644 (file)
--- a/liblttng-ust/lttng-ust-comm.c
+++ b/liblttng-ust/lttng-ust-comm.c
@@ -1,22 +1,8 @@
 /*
- * lttng-ust-comm.c
+ * SPDX-License-Identifier: LGPL-2.1-only
  *
  * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; only
- * version 2.1 of the License.
- *
- * This library 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
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #define _LGPL_SOURCE
@@ -63,6 +49,7 @@
 #include "../libringbuffer/getcpu.h"
 #include "getenv.h"
 #include "ust-events-internal.h"
+#include "context-internal.h"
 
 /* Concatenate lttng ust shared library name with its major version number. */
 #define LTTNG_UST_LIB_SO_NAME "liblttng-ust.so." __ust_stringify(CONFIG_LTTNG_UST_LIBRARY_VERSION_MAJOR)
@@ -358,6 +345,7 @@ static const char *cmd_name_mapping[] = {
        /* Counter commands */
        [ LTTNG_UST_COUNTER_GLOBAL ] = "Create Counter Global",
        [ LTTNG_UST_COUNTER_CPU ] = "Create Counter CPU",
+       [ LTTNG_UST_COUNTER_EVENT ] = "Create Counter Event",
 };
 
 static const char *str_timeout;
@@ -1306,7 +1294,48 @@ int handle_message(struct sock_info *sock_info,
                        ret = -ENOSYS;
                break;
        }
+       case LTTNG_UST_COUNTER_EVENT:
+       {
+               /* Receive struct lttng_ust_counter_event */
+               struct lttng_ust_counter_event counter_event;
 
+               if (sizeof(counter_event) != lum->u.counter_event.len) {
+                       DBG("incorrect counter event data message size: %u", lum->u.counter_event.len);
+                       ret = -EINVAL;
+                       goto error;
+               }
+               len = ustcomm_recv_unix_sock(sock, &counter_event, sizeof(counter_event));
+               switch (len) {
+               case 0: /* orderly shutdown */
+                       ret = 0;
+                       goto error;
+               default:
+                       if (len == sizeof(counter_event)) {
+                               DBG("counter event data received");
+                               break;
+                       } else if (len < 0) {
+                               DBG("Receive failed from lttng-sessiond with errno %d", (int) -len);
+                               if (len == -ECONNRESET) {
+                                       ERR("%s remote end closed connection", sock_info->name);
+                                       ret = len;
+                                       goto error;
+                               }
+                               ret = len;
+                               goto error;
+                       } else {
+                               DBG("incorrect event notifier data message size: %zd", len);
+                               ret = -EINVAL;
+                               goto error;
+                       }
+               }
+               if (ops->cmd)
+                       ret = ops->cmd(lum->handle, lum->cmd,
+                                       (unsigned long) &counter_event,
+                                       &args, sock_info);
+               else
+                       ret = -ENOSYS;
+               break;
+       }
        default:
                if (ops->cmd)
                        ret = ops->cmd(lum->handle, lum->cmd,