src/common/notification.c

   1 /*
   2  * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #include <lttng/notification/notification-internal.h>
   9 #include <lttng/condition/condition-internal.h>
  10 #include <lttng/condition/evaluation-internal.h>
  11 #include <lttng/condition/condition.h>
  12 #include <lttng/condition/evaluation.h>
  13 #include <lttng/trigger/trigger-internal.h>
  14 #include <common/payload.h>
  15 #include <common/payload-view.h>
  16
  17 struct lttng_notification *lttng_notification_create(
  18                 struct lttng_trigger *trigger,
  19                 struct lttng_evaluation *evaluation)
  20 {
  21         struct lttng_notification *notification = NULL;
  22
  23         if (!trigger || !evaluation) {
  24                 goto end;
  25         }
  26
  27         notification = zmalloc(sizeof(struct lttng_notification));
  28         if (!notification) {
  29                 goto end;
  30         }
  31
  32         notification->trigger = trigger;
  33         notification->evaluation = evaluation;
  34 end:
  35         return notification;
  36 }
  37
  38 int lttng_notification_serialize(const struct lttng_notification *notification,
  39                 struct lttng_payload *payload)
  40 {
  41         int ret;
  42         size_t header_offset, size_before_payload;
  43         struct lttng_notification_comm notification_comm = { 0 };
  44         struct lttng_notification_comm *header;
  45
  46         header_offset = payload->buffer.size;
  47         ret = lttng_dynamic_buffer_append(&payload->buffer, &notification_comm,
  48                         sizeof(notification_comm));
  49         if (ret) {
  50                 goto end;
  51         }
  52
  53         size_before_payload = payload->buffer.size;
  54         ret = lttng_trigger_serialize(notification->trigger,
  55                         payload);
  56         if (ret) {
  57                 goto end;
  58         }
  59
  60         ret = lttng_evaluation_serialize(notification->evaluation, payload);
  61         if (ret) {
  62                 goto end;
  63         }
  64
  65         /* Update payload size. */
  66         header = (typeof(header)) (payload->buffer.data + header_offset);
  67         header->length = (uint32_t) (payload->buffer.size - size_before_payload);
  68 end:
  69         return ret;
  70
  71 }
  72
  73 ssize_t lttng_notification_create_from_payload(
  74                 struct lttng_payload_view *src_view,
  75                 struct lttng_notification **notification)
  76 {
  77         ssize_t ret, notification_size = 0, trigger_size, evaluation_size;
  78         struct lttng_trigger *trigger = NULL;
  79         struct lttng_evaluation *evaluation = NULL;
  80         const struct lttng_notification_comm *notification_comm;
  81         const struct lttng_payload_view notification_comm_view =
  82                         lttng_payload_view_from_view(
  83                                         src_view, 0, sizeof(*notification_comm));
  84
  85         if (!src_view || !notification) {
  86                 ret = -1;
  87                 goto error;
  88         }
  89
  90         if (!lttng_payload_view_is_valid(&notification_comm_view)) {
  91                 /* Payload not large enough to contain the header. */
  92                 ret = -1;
  93                 goto error;
  94         }
  95
  96         notification_comm = (typeof(notification_comm)) notification_comm_view.buffer.data;
  97         notification_size += sizeof(*notification_comm);
  98         {
  99                 /* struct lttng_condition */
 100                 struct lttng_payload_view condition_view =
 101                                 lttng_payload_view_from_view(src_view,
 102                                                 notification_size, -1);
 103
 104                 trigger_size = lttng_trigger_create_from_payload(
 105                                 &condition_view, &trigger);
 106         }
 107
 108         if (trigger_size < 0) {
 109                 ret = trigger_size;
 110                 goto error;
 111         }
 112
 113         notification_size += trigger_size;
 114
 115         {
 116                 /* struct lttng_evaluation */
 117                 struct lttng_payload_view evaluation_view =
 118                                 lttng_payload_view_from_view(src_view,
 119                                                 notification_size, -1);
 120
 121                 evaluation_size = lttng_evaluation_create_from_payload(
 122                                 lttng_trigger_get_const_condition(trigger),
 123                                 &evaluation_view, &evaluation);
 124         }
 125
 126         if (evaluation_size < 0) {
 127                 ret = evaluation_size;
 128                 goto error;
 129         }
 130
 131         notification_size += evaluation_size;
 132
 133         /* Unexpected size of inner-elements; the buffer is corrupted. */
 134         if ((ssize_t) notification_comm->length !=
 135                         trigger_size + evaluation_size) {
 136                 ret = -1;
 137                 goto error;
 138         }
 139
 140         *notification = lttng_notification_create(trigger, evaluation);
 141         if (!*notification) {
 142                 ret = -1;
 143                 goto error;
 144         }
 145
 146         ret = notification_size;
 147         return ret;
 148
 149 error:
 150         lttng_trigger_destroy(trigger);
 151         lttng_evaluation_destroy(evaluation);
 152         return ret;
 153 }
 154
 155 void lttng_notification_destroy(struct lttng_notification *notification)
 156 {
 157         if (!notification) {
 158                 return;
 159         }
 160
 161         lttng_trigger_destroy(notification->trigger);
 162         lttng_evaluation_destroy(notification->evaluation);
 163         free(notification);
 164 }
 165
 166 const struct lttng_condition *lttng_notification_get_condition(
 167                 struct lttng_notification *notification)
 168 {
 169         return notification ? lttng_trigger_get_const_condition(notification->trigger) : NULL;
 170 }
 171
 172 const struct lttng_evaluation *lttng_notification_get_evaluation(
 173                 struct lttng_notification *notification)
 174 {
 175         return notification ? notification->evaluation : NULL;
 176 }
 177
 178 const struct lttng_trigger *lttng_notification_get_trigger(
 179                 struct lttng_notification *notification)
 180 {
 181         return notification ? notification->trigger : NULL;
 182 }