src/common/actions/start-session.c

   1 /*
   2  * Copyright (C) 2019 Simon Marchi <simon.marchi@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 <common/macros.h>
  11 #include <lttng/action/action-internal.h>
  12 #include <lttng/action/firing-policy-internal.h>
  13 #include <lttng/action/firing-policy.h>
  14 #include <lttng/action/start-session-internal.h>
  15 #include <lttng/action/start-session.h>
  16
  17 #define IS_START_SESSION_ACTION(action) \
  18         (lttng_action_get_type(action) == LTTNG_ACTION_TYPE_START_SESSION)
  19
  20 struct lttng_action_start_session {
  21         struct lttng_action parent;
  22
  23         /* Owned by this. */
  24         char *session_name;
  25         struct lttng_firing_policy *policy;
  26 };
  27
  28 struct lttng_action_start_session_comm {
  29         /* Includes the trailing \0. */
  30         uint32_t session_name_len;
  31
  32         /*
  33          * Variable data:
  34          *
  35          *  - session name (null terminated)
  36          *  - policy
  37          */
  38         char data[];
  39 } LTTNG_PACKED;
  40
  41 static const struct lttng_firing_policy *
  42 lttng_action_start_session_internal_get_firing_policy(
  43                 const struct lttng_action *action);
  44
  45 static struct lttng_action_start_session *action_start_session_from_action(
  46                 struct lttng_action *action)
  47 {
  48         assert(action);
  49
  50         return container_of(action, struct lttng_action_start_session, parent);
  51 }
  52
  53 static const struct lttng_action_start_session *
  54 action_start_session_from_action_const(const struct lttng_action *action)
  55 {
  56         assert(action);
  57
  58         return container_of(action, struct lttng_action_start_session, parent);
  59 }
  60
  61 static bool lttng_action_start_session_validate(struct lttng_action *action)
  62 {
  63         bool valid;
  64         struct lttng_action_start_session *action_start_session;
  65
  66         if (!action) {
  67                 valid = false;
  68                 goto end;
  69         }
  70
  71         action_start_session = action_start_session_from_action(action);
  72
  73         /* A non-empty session name is mandatory. */
  74         if (!action_start_session->session_name ||
  75                         strlen(action_start_session->session_name) == 0) {
  76                 valid = false;
  77                 goto end;
  78         }
  79
  80         valid = true;
  81 end:
  82         return valid;
  83 }
  84
  85 static bool lttng_action_start_session_is_equal(
  86                 const struct lttng_action *_a, const struct lttng_action *_b)
  87 {
  88         bool is_equal = false;
  89         struct lttng_action_start_session *a, *b;
  90
  91         a = container_of(_a, struct lttng_action_start_session, parent);
  92         b = container_of(_b, struct lttng_action_start_session, parent);
  93
  94         /* Action is not valid if this is not true. */
  95         assert(a->session_name);
  96         assert(b->session_name);
  97         if (strcmp(a->session_name, b->session_name)) {
  98                 goto end;
  99         }
 100
 101         is_equal = lttng_firing_policy_is_equal(a->policy, b->policy);
 102 end:
 103         return is_equal;
 104 }
 105
 106 static int lttng_action_start_session_serialize(
 107                 struct lttng_action *action, struct lttng_payload *payload)
 108 {
 109         struct lttng_action_start_session *action_start_session;
 110         struct lttng_action_start_session_comm comm;
 111         size_t session_name_len;
 112         int ret;
 113
 114         assert(action);
 115         assert(payload);
 116
 117         action_start_session = action_start_session_from_action(action);
 118
 119         assert(action_start_session->session_name);
 120
 121         DBG("Serializing start session action: session-name: %s",
 122                         action_start_session->session_name);
 123
 124         session_name_len = strlen(action_start_session->session_name) + 1;
 125         comm.session_name_len = session_name_len;
 126
 127         ret = lttng_dynamic_buffer_append(&payload->buffer, &comm, sizeof(comm));
 128         if (ret) {
 129                 ret = -1;
 130                 goto end;
 131         }
 132
 133         ret = lttng_dynamic_buffer_append(&payload->buffer,
 134                         action_start_session->session_name, session_name_len);
 135         if (ret) {
 136                 ret = -1;
 137                 goto end;
 138         }
 139
 140         ret = lttng_firing_policy_serialize(
 141                         action_start_session->policy, payload);
 142         if (ret) {
 143                 ret = -1;
 144                 goto end;
 145         }
 146
 147         ret = 0;
 148 end:
 149         return ret;
 150 }
 151
 152 static void lttng_action_start_session_destroy(struct lttng_action *action)
 153 {
 154         struct lttng_action_start_session *action_start_session;
 155
 156         if (!action) {
 157                 goto end;
 158         }
 159
 160         action_start_session = action_start_session_from_action(action);
 161
 162         lttng_firing_policy_destroy(action_start_session->policy);
 163         free(action_start_session->session_name);
 164         free(action_start_session);
 165
 166 end:
 167         return;
 168 }
 169
 170 ssize_t lttng_action_start_session_create_from_payload(
 171                 struct lttng_payload_view *view,
 172                 struct lttng_action **p_action)
 173 {
 174         ssize_t consumed_len, ret;
 175         const struct lttng_action_start_session_comm *comm;
 176         const char *session_name;
 177         struct lttng_action *action = NULL;
 178         enum lttng_action_status status;
 179         struct lttng_firing_policy *policy = NULL;
 180
 181         comm = (typeof(comm)) view->buffer.data;
 182         session_name = (const char *) &comm->data;
 183
 184         /* Session name */
 185         if (!lttng_buffer_view_contains_string(&view->buffer, session_name,
 186                             comm->session_name_len)) {
 187                 consumed_len = -1;
 188                 goto end;
 189         }
 190         consumed_len = sizeof(*comm) + comm->session_name_len;
 191
 192         /* Firing policy. */
 193         {
 194                 struct lttng_payload_view policy_view =
 195                                 lttng_payload_view_from_view(
 196                                                 view, consumed_len, -1);
 197                 ret = lttng_firing_policy_create_from_payload(
 198                                 &policy_view, &policy);
 199                 if (ret < 0) {
 200                         consumed_len = -1;
 201                         goto end;
 202                 }
 203                 consumed_len += ret;
 204         }
 205
 206         action = lttng_action_start_session_create();
 207         if (!action) {
 208                 consumed_len = -1;
 209                 goto end;
 210         }
 211
 212         status = lttng_action_start_session_set_session_name(
 213                         action, session_name);
 214         if (status != LTTNG_ACTION_STATUS_OK) {
 215                 consumed_len = -1;
 216                 goto end;
 217         }
 218
 219         assert(policy);
 220         status = lttng_action_start_session_set_firing_policy(action, policy);
 221         if (status != LTTNG_ACTION_STATUS_OK) {
 222                 consumed_len = -1;
 223                 goto end;
 224         }
 225
 226         *p_action = action;
 227         action = NULL;
 228
 229 end:
 230         lttng_firing_policy_destroy(policy);
 231         lttng_action_start_session_destroy(action);
 232
 233         return consumed_len;
 234 }
 235
 236 struct lttng_action *lttng_action_start_session_create(void)
 237 {
 238         struct lttng_action *action = NULL;
 239         struct lttng_firing_policy *policy = NULL;
 240         enum lttng_action_status status;
 241
 242         /* Create a every N = 1 firing policy. */
 243         policy = lttng_firing_policy_every_n_create(1);
 244         if (!policy) {
 245                 goto end;
 246         }
 247
 248         action = zmalloc(sizeof(struct lttng_action_start_session));
 249         if (!action) {
 250                 goto end;
 251         }
 252
 253         lttng_action_init(action, LTTNG_ACTION_TYPE_START_SESSION,
 254                         lttng_action_start_session_validate,
 255                         lttng_action_start_session_serialize,
 256                         lttng_action_start_session_is_equal,
 257                         lttng_action_start_session_destroy,
 258                         lttng_action_start_session_internal_get_firing_policy);
 259
 260         status = lttng_action_start_session_set_firing_policy(action, policy);
 261         if (status != LTTNG_ACTION_STATUS_OK) {
 262                 free(action);
 263                 action = NULL;
 264                 goto end;
 265         }
 266
 267 end:
 268         lttng_firing_policy_destroy(policy);
 269         return action;
 270 }
 271
 272 enum lttng_action_status lttng_action_start_session_set_session_name(
 273                 struct lttng_action *action, const char *session_name)
 274 {
 275         struct lttng_action_start_session *action_start_session;
 276         enum lttng_action_status status;
 277
 278         if (!action || !IS_START_SESSION_ACTION(action) || !session_name ||
 279                         strlen(session_name) == 0) {
 280                 status = LTTNG_ACTION_STATUS_INVALID;
 281                 goto end;
 282         }
 283
 284         action_start_session = action_start_session_from_action(action);
 285
 286         free(action_start_session->session_name);
 287
 288         action_start_session->session_name = strdup(session_name);
 289         if (!action_start_session->session_name) {
 290                 status = LTTNG_ACTION_STATUS_ERROR;
 291                 goto end;
 292         }
 293
 294         status = LTTNG_ACTION_STATUS_OK;
 295 end:
 296         return status;
 297 }
 298
 299 enum lttng_action_status lttng_action_start_session_get_session_name(
 300                 const struct lttng_action *action, const char **session_name)
 301 {
 302         const struct lttng_action_start_session *action_start_session;
 303         enum lttng_action_status status;
 304
 305         if (!action || !IS_START_SESSION_ACTION(action) || !session_name) {
 306                 status = LTTNG_ACTION_STATUS_INVALID;
 307                 goto end;
 308         }
 309
 310         action_start_session = action_start_session_from_action_const(action);
 311
 312         *session_name = action_start_session->session_name;
 313
 314         status = LTTNG_ACTION_STATUS_OK;
 315 end:
 316         return status;
 317 }
 318
 319 enum lttng_action_status lttng_action_start_session_set_firing_policy(
 320                 struct lttng_action *action,
 321                 const struct lttng_firing_policy *policy)
 322 {
 323         enum lttng_action_status status;
 324         struct lttng_action_start_session *start_session_action;
 325         struct lttng_firing_policy *copy = NULL;
 326
 327         if (!action || !policy || !IS_START_SESSION_ACTION(action)) {
 328                 status = LTTNG_ACTION_STATUS_INVALID;
 329                 goto end;
 330         }
 331
 332         copy = lttng_firing_policy_copy(policy);
 333         if (!copy) {
 334                 status = LTTNG_ACTION_STATUS_ERROR;
 335                 goto end;
 336         }
 337
 338         start_session_action = action_start_session_from_action(action);
 339
 340         /* Release the previous firing policy .*/
 341         lttng_firing_policy_destroy(start_session_action->policy);
 342
 343         /* Assign the policy. */
 344         start_session_action->policy = copy;
 345         status = LTTNG_ACTION_STATUS_OK;
 346         copy = NULL;
 347
 348 end:
 349         lttng_firing_policy_destroy(copy);
 350         return status;
 351 }
 352
 353 enum lttng_action_status lttng_action_start_session_get_firing_policy(
 354                 const struct lttng_action *action,
 355                 const struct lttng_firing_policy **policy)
 356 {
 357         enum lttng_action_status status;
 358         const struct lttng_action_start_session *start_session_action;
 359
 360         if (!action || !policy || !IS_START_SESSION_ACTION(action)) {
 361                 status = LTTNG_ACTION_STATUS_INVALID;
 362                 goto end;
 363         }
 364
 365         start_session_action = action_start_session_from_action_const(action);
 366
 367         *policy = start_session_action->policy;
 368         status = LTTNG_ACTION_STATUS_OK;
 369 end:
 370         return status;
 371 }
 372
 373 static const struct lttng_firing_policy *
 374 lttng_action_start_session_internal_get_firing_policy(
 375                 const struct lttng_action *action)
 376 {
 377         const struct lttng_action_start_session *_action;
 378         _action = action_start_session_from_action_const(action);
 379
 380         return _action->policy;
 381 }