+++ /dev/null
-/*
- * lttng-context-procname.c
- *
- * LTTng UST procname 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 <lttng/ust-events.h>
-#include <lttng/ust-tracer.h>
-#include <lttng/ringbuffer-config.h>
-#include <assert.h>
-#include "compat.h"
-
-/*
- * We cache the result to ensure we don't trigger a system call for
- * each event.
- * Upon exec, procname changes, but exec takes care of throwing away
- * this cached version.
- * The procname can also change by calling prctl(). The procname should
- * be set for a thread before the first event is logged within this
- * thread.
- */
-static __thread char cached_procname[17];
-
-static inline
-char *wrapper_getprocname(void)
-{
- if (caa_unlikely(!cached_procname[0])) {
- lttng_ust_getprocname(cached_procname);
- cached_procname[LTTNG_UST_PROCNAME_LEN - 1] = '\0';
- }
- return cached_procname;
-}
-
-void lttng_context_procname_reset(void)
-{
- cached_procname[0] = '\0';
-}
-
-static
-size_t procname_get_size(size_t offset)
-{
- size_t size = 0;
-
- size += LTTNG_UST_PROCNAME_LEN;
- return size;
-}
-
-static
-void procname_record(struct lttng_ctx_field *field,
- struct lttng_ust_lib_ring_buffer_ctx *ctx,
- struct ltt_channel *chan)
-{
- char *procname;
-
- procname = wrapper_getprocname();
- chan->ops->event_write(ctx, procname, LTTNG_UST_PROCNAME_LEN);
-}
-
-int lttng_add_procname_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, "procname")) {
- lttng_remove_context_field(ctx, field);
- return -EEXIST;
- }
- field->event_field.name = "procname";
- 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_UST_PROCNAME_LEN;
- field->get_size = procname_get_size;
- field->record = procname_record;
- return 0;
-}
-
-/*
- * Force a read (imply TLS fixup for dlopen) of TLS variables.
- */
-void lttng_fixup_procname_tls(void)
-{
- asm volatile ("" : : "m" (cached_procname[0]));
-}