X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=lttng-context-hostname.c;h=6f9d130cb6acfbef5747e403bba97285521017b2;hb=b7cdc18250880cc44edeef4a4b42c8ac7a135a6d;hp=15aabe63c3f18bb31800f9b7ed61fc14dd6a859d;hpb=a9dd15dadd7d58f58cfd19d2503d3b6b541723bc;p=lttng-modules.git

diff --git a/lttng-context-hostname.c b/lttng-context-hostname.c
index 15aabe63..6f9d130c 100644
--- a/lttng-context-hostname.c
+++ b/lttng-context-hostname.c
@@ -1,33 +1,20 @@
-/*
+/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
+ *
  * lttng-context-hostname.c
  *
  * LTTng hostname context.
  *
  * Copyright (C) 2009-2012 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
  */
 
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/utsname.h>
-#include "lttng-events.h"
-#include "wrapper/ringbuffer/frontend_types.h"
-#include "wrapper/vmalloc.h"
-#include "lttng-tracer.h"
+#include <lttng-events.h>
+#include <wrapper/ringbuffer/frontend_types.h>
+#include <wrapper/vmalloc.h>
+#include <lttng-tracer.h>
 
 #define LTTNG_HOSTNAME_CTX_LEN	(__NEW_UTS_LEN + 1)
 
@@ -65,6 +52,29 @@ void hostname_record(struct lttng_ctx_field *field,
 	}
 }
 
+static
+void hostname_get_value(struct lttng_ctx_field *field,
+		struct lttng_probe_ctx *lttng_probe_ctx,
+		union lttng_ctx_value *value)
+{
+	struct nsproxy *nsproxy;
+	struct uts_namespace *ns;
+	char *hostname;
+
+	/*
+	 * No need to take the RCU read-side lock to read current
+	 * nsproxy. (documented in nsproxy.h)
+	 */
+	nsproxy = current->nsproxy;
+	if (nsproxy) {
+		ns = nsproxy->uts_ns;
+		hostname = ns->name.nodename;
+	} else {
+		hostname = "";
+	}
+	value->str = hostname;
+}
+
 int lttng_add_hostname_to_ctx(struct lttng_ctx **ctx)
 {
 	struct lttng_ctx_field *field;
@@ -89,16 +99,9 @@ int lttng_add_hostname_to_ctx(struct lttng_ctx **ctx)
 
 	field->get_size = hostname_get_size;
 	field->record = hostname_record;
+	field->get_value = hostname_get_value;
 	lttng_context_update(*ctx);
 	wrapper_vmalloc_sync_all();
 	return 0;
 }
 EXPORT_SYMBOL_GPL(lttng_add_hostname_to_ctx);
-
-MODULE_LICENSE("GPL and additional rights");
-MODULE_AUTHOR("Mathieu Desnoyers");
-MODULE_DESCRIPTION("Linux Trace Toolkit Perf Support");
-MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
-	__stringify(LTTNG_MODULES_MINOR_VERSION) "."
-	__stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
-	LTTNG_MODULES_EXTRAVERSION);