liblttng-ust/ust-core.c

   1 /*
   2  * ust-core.c
   3  *
   4  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; only
   9  * version 2.1 of the License.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <lttng/usterr-signal-safe.h>
  22 #include <lttng/ust-events.h>
  23 #include <stdlib.h>
  24
  25 CDS_LIST_HEAD(ltt_transport_list);
  26
  27 volatile enum ust_loglevel ust_loglevel;
  28
  29 void init_usterr(void)
  30 {
  31         char *ust_debug;
  32
  33         if (ust_loglevel == UST_LOGLEVEL_UNKNOWN) {
  34                 ust_debug = getenv("LTTNG_UST_DEBUG");
  35                 if (ust_debug)
  36                         ust_loglevel = UST_LOGLEVEL_DEBUG;
  37                 else
  38                         ust_loglevel = UST_LOGLEVEL_NORMAL;
  39         }
  40 }
  41
  42 struct ltt_transport *ltt_transport_find(const char *name)
  43 {
  44         struct ltt_transport *transport;
  45
  46         cds_list_for_each_entry(transport, &ltt_transport_list, node) {
  47                 if (!strcmp(transport->name, name))
  48                         return transport;
  49         }
  50         return NULL;
  51 }
  52
  53 /**
  54  * ltt_transport_register - LTT transport registration
  55  * @transport: transport structure
  56  *
  57  * Registers a transport which can be used as output to extract the data out of
  58  * LTTng. Called with ust_lock held.
  59  */
  60 void ltt_transport_register(struct ltt_transport *transport)
  61 {
  62         cds_list_add_tail(&transport->node, &ltt_transport_list);
  63 }
  64
  65 /**
  66  * ltt_transport_unregister - LTT transport unregistration
  67  * @transport: transport structure
  68  * Called with ust_lock held.
  69  */
  70 void ltt_transport_unregister(struct ltt_transport *transport)
  71 {
  72         cds_list_del(&transport->node);
  73 }