/usr/src/lttng-modules-2.7.1/lttng-context-hostname.c is in lttng-modules-dkms 2.7.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 | /*
* 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"
#define LTTNG_HOSTNAME_CTX_LEN (__NEW_UTS_LEN + 1)
static
size_t hostname_get_size(size_t offset)
{
size_t size = 0;
size += LTTNG_HOSTNAME_CTX_LEN;
return size;
}
static
void hostname_record(struct lttng_ctx_field *field,
struct lib_ring_buffer_ctx *ctx,
struct lttng_channel *chan)
{
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;
chan->ops->event_write(ctx, hostname,
LTTNG_HOSTNAME_CTX_LEN);
} else {
chan->ops->event_memset(ctx, 0,
LTTNG_HOSTNAME_CTX_LEN);
}
}
static
void hostname_get_value(struct lttng_ctx_field *field,
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;
field = lttng_append_context(ctx);
if (!field)
return -ENOMEM;
if (lttng_find_context(*ctx, "hostname")) {
lttng_remove_context_field(ctx, field);
return -EEXIST;
}
field->event_field.name = "hostname";
field->event_field.type.atype = atype_array;
field->event_field.type.u.array.elem_type.atype = atype_integer;
field->event_field.type.u.array.elem_type.u.basic.integer.size = sizeof(char) * CHAR_BIT;
field->event_field.type.u.array.elem_type.u.basic.integer.alignment = lttng_alignof(char) * CHAR_BIT;
field->event_field.type.u.array.elem_type.u.basic.integer.signedness = lttng_is_signed_type(char);
field->event_field.type.u.array.elem_type.u.basic.integer.reverse_byte_order = 0;
field->event_field.type.u.array.elem_type.u.basic.integer.base = 10;
field->event_field.type.u.array.elem_type.u.basic.integer.encoding = lttng_encode_UTF8;
field->event_field.type.u.array.length = LTTNG_HOSTNAME_CTX_LEN;
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);
|