src/lib/lttng-ctl/event.c

   1 /*
   2  * event.c
   3  *
   4  * Linux Trace Toolkit Control Library
   5  *
   6  * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   7  *
   8  * This library is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License, version 2.1 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public License
  18  * along with this library; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #define _LGPL_SOURCE
  23 #include <lttng/event.h>
  24 #include <lttng/lttng-error.h>
  25 #include <stddef.h>
  26 #include <common/sessiond-comm/sessiond-comm.h>
  27
  28 int lttng_event_get_filter_expression(struct lttng_event *event,
  29         const char **filter_expression)
  30 {
  31         int ret = 0;
  32         struct lttcomm_event_extended_header *ext_header;
  33
  34         if (!event || !filter_expression) {
  35                 ret = -LTTNG_ERR_INVALID;
  36                 goto end;
  37         }
  38
  39         ext_header = event->extended.ptr;
  40
  41         if (!ext_header) {
  42                 /*
  43                  * This can happen since the lttng_event structure is
  44                  * used for other tasks where this pointer is never set.
  45                  */
  46                 *filter_expression = NULL;
  47                 goto end;
  48         }
  49
  50         if (ext_header->filter_len) {
  51                 *filter_expression = ((const char *) (ext_header)) +
  52                                 sizeof(*ext_header);
  53         } else {
  54                 *filter_expression = NULL;
  55         }
  56
  57 end:
  58         return ret;
  59 }
  60
  61 int lttng_event_get_exclusion_name_count(struct lttng_event *event)
  62 {
  63         int ret;
  64         struct lttcomm_event_extended_header *ext_header;
  65
  66         if (!event) {
  67                 ret = -LTTNG_ERR_INVALID;
  68                 goto end;
  69         }
  70
  71         ext_header = event->extended.ptr;
  72         if (!ext_header) {
  73                 /*
  74                  * This can happen since the lttng_event structure is
  75                  * used for other tasks where this pointer is never set.
  76                  */
  77                 ret = 0;
  78                 goto end;
  79         }
  80
  81         if (ext_header->nb_exclusions > INT_MAX) {
  82                 ret = -LTTNG_ERR_OVERFLOW;
  83                 goto end;
  84         }
  85         ret = (int) ext_header->nb_exclusions;
  86 end:
  87         return ret;
  88 }
  89
  90 int lttng_event_get_exclusion_name(struct lttng_event *event,
  91                 size_t index, const char **exclusion_name)
  92 {
  93         int ret = 0;
  94         struct lttcomm_event_extended_header *ext_header;
  95         void *at;
  96
  97         if (!event || !exclusion_name) {
  98                 ret = -LTTNG_ERR_INVALID;
  99                 goto end;
 100         }
 101
 102         ext_header = event->extended.ptr;
 103         if (!ext_header) {
 104                 ret = -LTTNG_ERR_INVALID;
 105                 goto end;
 106         }
 107
 108         if (index >= ext_header->nb_exclusions) {
 109                 ret = -LTTNG_ERR_INVALID;
 110                 goto end;
 111         }
 112
 113         at = (void *) ext_header + sizeof(*ext_header);
 114         at += ext_header->filter_len;
 115         at += index * LTTNG_SYMBOL_NAME_LEN;
 116         *exclusion_name = at;
 117
 118 end:
 119         return ret;
 120 }