src/common/notification.c

   1 /*
   2  * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * This library is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU Lesser General Public License, version 2.1 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This library is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
  11  * for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this library; if not, write to the Free Software Foundation,
  15  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  16  */
  17
  18 #include <lttng/notification/notification-internal.h>
  19 #include <lttng/condition/condition-internal.h>
  20 #include <lttng/condition/evaluation-internal.h>
  21 #include <lttng/condition/condition.h>
  22 #include <lttng/condition/evaluation.h>
  23 #include <assert.h>
  24
  25 LTTNG_HIDDEN
  26 struct lttng_notification *lttng_notification_create(
  27                 struct lttng_condition *condition,
  28                 struct lttng_evaluation *evaluation)
  29 {
  30         struct lttng_notification *notification = NULL;
  31
  32         if (!condition || !evaluation) {
  33                 goto end;
  34         }
  35
  36         notification = zmalloc(sizeof(struct lttng_notification));
  37         if (!notification) {
  38                 goto end;
  39         }
  40
  41         notification->condition = condition;
  42         notification->evaluation = evaluation;
  43         notification->owns_elements = false;
  44 end:
  45         return notification;
  46 }
  47
  48 LTTNG_HIDDEN
  49 ssize_t lttng_notification_serialize(struct lttng_notification *notification,
  50                 char *buf)
  51 {
  52         ssize_t ret, condition_size, evaluation_size, offset = 0;
  53         struct lttng_notification_comm notification_comm;
  54
  55         if (!notification) {
  56                 ret = -1;
  57                 goto end;
  58         }
  59
  60         offset += sizeof(notification_comm);
  61         condition_size = lttng_condition_serialize(notification->condition,
  62                         buf ? (buf + offset) : NULL);
  63         if (condition_size < 0) {
  64                 ret = condition_size;
  65                 goto end;
  66         }
  67         offset += condition_size;
  68
  69         evaluation_size = lttng_evaluation_serialize(notification->evaluation,
  70                         buf ? (buf + offset) : NULL);
  71         if (evaluation_size < 0) {
  72                 ret = evaluation_size;
  73                 goto end;
  74         }
  75         offset += evaluation_size;
  76
  77         if (buf) {
  78                 notification_comm.length =
  79                                 (uint32_t) (condition_size + evaluation_size);
  80                 memcpy(buf, &notification_comm, sizeof(notification_comm));
  81         }
  82         ret = offset;
  83 end:
  84         return ret;
  85
  86 }
  87
  88 LTTNG_HIDDEN
  89 ssize_t lttng_notification_create_from_buffer(const char *buf,
  90                 struct lttng_notification **notification)
  91 {
  92         ssize_t ret, offset = 0, condition_size, evaluation_size;
  93         struct lttng_notification_comm *notification_comm;
  94         struct lttng_condition *condition;
  95         struct lttng_evaluation *evaluation;
  96
  97         if (!buf || !notification) {
  98                 ret = -1;
  99                 goto end;
 100         }
 101
 102         notification_comm = (struct lttng_notification_comm *) buf;
 103         offset += sizeof(*notification_comm);
 104
 105         /* struct lttng_condition */
 106         condition_size = lttng_condition_create_from_buffer(buf + offset,
 107                         &condition);
 108         if (condition_size < 0) {
 109                 ret = condition_size;
 110                 goto end;
 111         }
 112         offset += condition_size;
 113
 114         /* struct lttng_evaluation */
 115         evaluation_size = lttng_evaluation_create_from_buffer(buf + offset,
 116                         &evaluation);
 117         if (evaluation_size < 0) {
 118                 ret = evaluation_size;
 119                 goto end;
 120         }
 121         offset += evaluation_size;
 122
 123         /* Unexpected size of inner-elements; the buffer is corrupted. */
 124         if ((ssize_t) notification_comm->length !=
 125                         condition_size + evaluation_size) {
 126                 ret = -1;
 127                 goto error;
 128         }
 129
 130         *notification = lttng_notification_create(condition, evaluation);
 131         if (!*notification) {
 132                 ret = -1;
 133                 goto error;
 134         }
 135         ret = offset;
 136         (*notification)->owns_elements = true;
 137 end:
 138         return ret;
 139 error:
 140         lttng_condition_destroy(condition);
 141         lttng_evaluation_destroy(evaluation);
 142         return ret;
 143 }
 144
 145 void lttng_notification_destroy(struct lttng_notification *notification)
 146 {
 147         if (!notification) {
 148                 return;
 149         }
 150
 151         if (notification->owns_elements) {
 152                 lttng_condition_destroy(notification->condition);
 153                 lttng_evaluation_destroy(notification->evaluation);
 154         }
 155         free(notification);
 156 }
 157
 158 struct lttng_condition *lttng_notification_get_condition(
 159                 struct lttng_notification *notification)
 160 {
 161         return notification ? notification->condition : NULL;
 162 }
 163
 164 struct lttng_evaluation *lttng_notification_get_evaluation(
 165                 struct lttng_notification *notification)
 166 {
 167         return notification ? notification->evaluation : NULL;
 168 }