src/common/actions/action.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 <assert.h>
   9 #include <common/error.h>
  10 #include <lttng/action/action-internal.h>
  11 #include <lttng/action/group-internal.h>
  12 #include <lttng/action/notify-internal.h>
  13 #include <lttng/action/rotate-session-internal.h>
  14 #include <lttng/action/snapshot-session-internal.h>
  15 #include <lttng/action/start-session-internal.h>
  16 #include <lttng/action/stop-session-internal.h>
  17
  18 LTTNG_HIDDEN
  19 const char *lttng_action_type_string(enum lttng_action_type action_type)
  20 {
  21         switch (action_type) {
  22         case LTTNG_ACTION_TYPE_UNKNOWN:
  23                 return "UNKNOWN";
  24         case LTTNG_ACTION_TYPE_GROUP:
  25                 return "GROUP";
  26         case LTTNG_ACTION_TYPE_NOTIFY:
  27                 return "NOTIFY";
  28         case LTTNG_ACTION_TYPE_ROTATE_SESSION:
  29                 return "ROTATE_SESSION";
  30         case LTTNG_ACTION_TYPE_SNAPSHOT_SESSION:
  31                 return "SNAPSHOT_SESSION";
  32         case LTTNG_ACTION_TYPE_START_SESSION:
  33                 return "START_SESSION";
  34         case LTTNG_ACTION_TYPE_STOP_SESSION:
  35                 return "STOP_SESSION";
  36         default:
  37                 return "???";
  38         }
  39 }
  40
  41 enum lttng_action_type lttng_action_get_type(const struct lttng_action *action)
  42 {
  43         return action ? action->type : LTTNG_ACTION_TYPE_UNKNOWN;
  44 }
  45
  46 LTTNG_HIDDEN
  47 void lttng_action_init(
  48                 struct lttng_action *action,
  49                 enum lttng_action_type type,
  50                 action_validate_cb validate,
  51                 action_serialize_cb serialize,
  52                 action_equal_cb equal,
  53                 action_destroy_cb destroy)
  54 {
  55         urcu_ref_init(&action->ref);
  56         action->type = type;
  57         action->validate = validate;
  58         action->serialize = serialize;
  59         action->equal = equal;
  60         action->destroy = destroy;
  61 }
  62
  63 static
  64 void action_destroy_ref(struct urcu_ref *ref)
  65 {
  66         struct lttng_action *action =
  67                         container_of(ref, struct lttng_action, ref);
  68
  69         action->destroy(action);
  70 }
  71
  72 LTTNG_HIDDEN
  73 void lttng_action_get(struct lttng_action *action)
  74 {
  75         urcu_ref_get(&action->ref);
  76 }
  77
  78 LTTNG_HIDDEN
  79 void lttng_action_put(struct lttng_action *action)
  80 {
  81         if (!action) {
  82                 return;
  83         }
  84
  85         assert(action->destroy);
  86         urcu_ref_put(&action->ref, action_destroy_ref);
  87 }
  88
  89 void lttng_action_destroy(struct lttng_action *action)
  90 {
  91         lttng_action_put(action);
  92 }
  93
  94 LTTNG_HIDDEN
  95 bool lttng_action_validate(struct lttng_action *action)
  96 {
  97         bool valid;
  98
  99         if (!action) {
 100                 valid = false;
 101                 goto end;
 102         }
 103
 104         if (!action->validate) {
 105                 /* Sub-class guarantees that it can never be invalid. */
 106                 valid = true;
 107                 goto end;
 108         }
 109
 110         valid = action->validate(action);
 111 end:
 112         return valid;
 113 }
 114
 115 LTTNG_HIDDEN
 116 int lttng_action_serialize(struct lttng_action *action,
 117                 struct lttng_payload *payload)
 118 {
 119         int ret;
 120         struct lttng_action_comm action_comm = {
 121                 .action_type = (int8_t) action->type,
 122         };
 123
 124         ret = lttng_dynamic_buffer_append(&payload->buffer, &action_comm,
 125                         sizeof(action_comm));
 126         if (ret) {
 127                 goto end;
 128         }
 129
 130         ret = action->serialize(action, payload);
 131         if (ret) {
 132                 goto end;
 133         }
 134 end:
 135         return ret;
 136 }
 137
 138 LTTNG_HIDDEN
 139 ssize_t lttng_action_create_from_payload(struct lttng_payload_view *view,
 140                 struct lttng_action **action)
 141 {
 142         ssize_t consumed_len, specific_action_consumed_len;
 143         const struct lttng_action_comm *action_comm;
 144         action_create_from_payload_cb create_from_payload_cb;
 145
 146         if (!view || !action) {
 147                 consumed_len = -1;
 148                 goto end;
 149         }
 150
 151         action_comm = (const struct lttng_action_comm *) view->buffer.data;
 152
 153         DBG("Create action from payload: action-type=%s",
 154                         lttng_action_type_string(action_comm->action_type));
 155
 156         switch (action_comm->action_type) {
 157         case LTTNG_ACTION_TYPE_NOTIFY:
 158                 create_from_payload_cb = lttng_action_notify_create_from_payload;
 159                 break;
 160         case LTTNG_ACTION_TYPE_ROTATE_SESSION:
 161                 create_from_payload_cb =
 162                                 lttng_action_rotate_session_create_from_payload;
 163                 break;
 164         case LTTNG_ACTION_TYPE_SNAPSHOT_SESSION:
 165                 create_from_payload_cb =
 166                                 lttng_action_snapshot_session_create_from_payload;
 167                 break;
 168         case LTTNG_ACTION_TYPE_START_SESSION:
 169                 create_from_payload_cb =
 170                                 lttng_action_start_session_create_from_payload;
 171                 break;
 172         case LTTNG_ACTION_TYPE_STOP_SESSION:
 173                 create_from_payload_cb =
 174                                 lttng_action_stop_session_create_from_payload;
 175                 break;
 176         case LTTNG_ACTION_TYPE_GROUP:
 177                 create_from_payload_cb = lttng_action_group_create_from_payload;
 178                 break;
 179         default:
 180                 ERR("Failed to create action from payload, unhandled action type: action-type=%u (%s)",
 181                                 action_comm->action_type,
 182                                 lttng_action_type_string(
 183                                                 action_comm->action_type));
 184                 consumed_len = -1;
 185                 goto end;
 186         }
 187
 188         {
 189                 /* Create buffer view for the action-type-specific data. */
 190                 struct lttng_payload_view specific_action_view =
 191                                 lttng_payload_view_from_view(view,
 192                                                 sizeof(struct lttng_action_comm),
 193                                                 -1);
 194
 195                 specific_action_consumed_len = create_from_payload_cb(
 196                                 &specific_action_view, action);
 197         }
 198         if (specific_action_consumed_len < 0) {
 199                 ERR("Failed to create specific action from buffer.");
 200                 consumed_len = -1;
 201                 goto end;
 202         }
 203
 204         assert(*action);
 205
 206         consumed_len = sizeof(struct lttng_action_comm) +
 207                        specific_action_consumed_len;
 208
 209 end:
 210         return consumed_len;
 211 }
 212
 213 LTTNG_HIDDEN
 214 bool lttng_action_is_equal(const struct lttng_action *a,
 215                 const struct lttng_action *b)
 216 {
 217         bool is_equal = false;
 218
 219         if (!a || !b) {
 220                 goto end;
 221         }
 222
 223         if (a->type != b->type) {
 224                 goto end;
 225         }
 226
 227         if (a == b) {
 228                 is_equal = true;
 229                 goto end;
 230         }
 231
 232         assert(a->equal);
 233         is_equal = a->equal(a, b);
 234 end:
 235         return is_equal;
 236 }