src/common/actions/start-session.cpp

   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 <common/error.hpp>
   9 #include <common/macros.hpp>
  10 #include <common/mi-lttng.hpp>
  11 #include <lttng/action/action-internal.hpp>
  12 #include <lttng/action/rate-policy-internal.hpp>
  13 #include <lttng/action/rate-policy.h>
  14 #include <lttng/action/start-session-internal.hpp>
  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_rate_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_rate_policy *
  42 lttng_action_start_session_internal_get_rate_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         LTTNG_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         LTTNG_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         LTTNG_ASSERT(a->session_name);
  96         LTTNG_ASSERT(b->session_name);
  97         if (strcmp(a->session_name, b->session_name)) {
  98                 goto end;
  99         }
 100
 101         is_equal = lttng_rate_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         LTTNG_ASSERT(action);
 115         LTTNG_ASSERT(payload);
 116
 117         action_start_session = action_start_session_from_action(action);
 118
 119         LTTNG_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_rate_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_rate_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_rate_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         /* Rate policy. */
 193         {
 194                 struct lttng_payload_view policy_view =
 195                                 lttng_payload_view_from_view(
 196                                                 view, consumed_len, -1);
 197                 ret = lttng_rate_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         LTTNG_ASSERT(policy);
 220         status = lttng_action_start_session_set_rate_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_rate_policy_destroy(policy);
 231         lttng_action_start_session_destroy(action);
 232
 233         return consumed_len;
 234 }
 235
 236 static enum lttng_error_code lttng_action_start_session_mi_serialize(
 237                 const struct lttng_action *action, struct mi_writer *writer)
 238 {
 239         int ret;
 240         enum lttng_error_code ret_code;
 241         enum lttng_action_status status;
 242         const char *session_name = NULL;
 243         const struct lttng_rate_policy *policy = NULL;
 244
 245         LTTNG_ASSERT(action);
 246         LTTNG_ASSERT(IS_START_SESSION_ACTION(action));
 247
 248         status = lttng_action_start_session_get_session_name(
 249                         action, &session_name);
 250         LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK);
 251         LTTNG_ASSERT(session_name != NULL);
 252
 253         status = lttng_action_start_session_get_rate_policy(action, &policy);
 254         LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK);
 255         LTTNG_ASSERT(policy != NULL);
 256
 257         /* Open action start session element. */
 258         ret = mi_lttng_writer_open_element(
 259                         writer, mi_lttng_element_action_start_session);
 260         if (ret) {
 261                 goto mi_error;
 262         }
 263
 264         /* Session name. */
 265         ret = mi_lttng_writer_write_element_string(
 266                         writer, mi_lttng_element_session_name, session_name);
 267         if (ret) {
 268                 goto mi_error;
 269         }
 270
 271         /* Rate policy. */
 272         ret_code = lttng_rate_policy_mi_serialize(policy, writer);
 273         if (ret_code != LTTNG_OK) {
 274                 goto end;
 275         }
 276
 277         /* Close action start session element. */
 278         ret = mi_lttng_writer_close_element(writer);
 279         if (ret) {
 280                 goto mi_error;
 281         }
 282
 283         ret_code = LTTNG_OK;
 284         goto end;
 285
 286 mi_error:
 287         ret_code = LTTNG_ERR_MI_IO_FAIL;
 288 end:
 289         return ret_code;
 290 }
 291
 292 struct lttng_action *lttng_action_start_session_create(void)
 293 {
 294         struct lttng_action_start_session *action_start = NULL;
 295         struct lttng_rate_policy *policy = NULL;
 296         enum lttng_action_status status;
 297
 298         /* Create a every N = 1 rate policy. */
 299         policy = lttng_rate_policy_every_n_create(1);
 300         if (!policy) {
 301                 goto end;
 302         }
 303
 304         action_start = zmalloc<lttng_action_start_session>();
 305         if (!action_start) {
 306                 goto end;
 307         }
 308
 309         lttng_action_init(&action_start->parent,
 310                         LTTNG_ACTION_TYPE_START_SESSION,
 311                         lttng_action_start_session_validate,
 312                         lttng_action_start_session_serialize,
 313                         lttng_action_start_session_is_equal,
 314                         lttng_action_start_session_destroy,
 315                         lttng_action_start_session_internal_get_rate_policy,
 316                         lttng_action_generic_add_error_query_results,
 317                         lttng_action_start_session_mi_serialize);
 318
 319         status = lttng_action_start_session_set_rate_policy(
 320                         &action_start->parent, policy);
 321         if (status != LTTNG_ACTION_STATUS_OK) {
 322                 lttng_action_destroy(&action_start->parent);
 323                 action_start = NULL;
 324                 goto end;
 325         }
 326
 327 end:
 328         lttng_rate_policy_destroy(policy);
 329         return &action_start->parent;
 330 }
 331
 332 enum lttng_action_status lttng_action_start_session_set_session_name(
 333                 struct lttng_action *action, const char *session_name)
 334 {
 335         struct lttng_action_start_session *action_start_session;
 336         enum lttng_action_status status;
 337
 338         if (!action || !IS_START_SESSION_ACTION(action) || !session_name ||
 339                         strlen(session_name) == 0) {
 340                 status = LTTNG_ACTION_STATUS_INVALID;
 341                 goto end;
 342         }
 343
 344         action_start_session = action_start_session_from_action(action);
 345
 346         free(action_start_session->session_name);
 347
 348         action_start_session->session_name = strdup(session_name);
 349         if (!action_start_session->session_name) {
 350                 status = LTTNG_ACTION_STATUS_ERROR;
 351                 goto end;
 352         }
 353
 354         status = LTTNG_ACTION_STATUS_OK;
 355 end:
 356         return status;
 357 }
 358
 359 enum lttng_action_status lttng_action_start_session_get_session_name(
 360                 const struct lttng_action *action, const char **session_name)
 361 {
 362         const struct lttng_action_start_session *action_start_session;
 363         enum lttng_action_status status;
 364
 365         if (!action || !IS_START_SESSION_ACTION(action) || !session_name) {
 366                 status = LTTNG_ACTION_STATUS_INVALID;
 367                 goto end;
 368         }
 369
 370         action_start_session = action_start_session_from_action_const(action);
 371
 372         *session_name = action_start_session->session_name;
 373
 374         status = LTTNG_ACTION_STATUS_OK;
 375 end:
 376         return status;
 377 }
 378
 379 enum lttng_action_status lttng_action_start_session_set_rate_policy(
 380                 struct lttng_action *action,
 381                 const struct lttng_rate_policy *policy)
 382 {
 383         enum lttng_action_status status;
 384         struct lttng_action_start_session *start_session_action;
 385         struct lttng_rate_policy *copy = NULL;
 386
 387         if (!action || !policy || !IS_START_SESSION_ACTION(action)) {
 388                 status = LTTNG_ACTION_STATUS_INVALID;
 389                 goto end;
 390         }
 391
 392         copy = lttng_rate_policy_copy(policy);
 393         if (!copy) {
 394                 status = LTTNG_ACTION_STATUS_ERROR;
 395                 goto end;
 396         }
 397
 398         start_session_action = action_start_session_from_action(action);
 399
 400         /* Release the previous rate policy .*/
 401         lttng_rate_policy_destroy(start_session_action->policy);
 402
 403         /* Assign the policy. */
 404         start_session_action->policy = copy;
 405         status = LTTNG_ACTION_STATUS_OK;
 406         copy = NULL;
 407
 408 end:
 409         lttng_rate_policy_destroy(copy);
 410         return status;
 411 }
 412
 413 enum lttng_action_status lttng_action_start_session_get_rate_policy(
 414                 const struct lttng_action *action,
 415                 const struct lttng_rate_policy **policy)
 416 {
 417         enum lttng_action_status status;
 418         const struct lttng_action_start_session *start_session_action;
 419
 420         if (!action || !policy || !IS_START_SESSION_ACTION(action)) {
 421                 status = LTTNG_ACTION_STATUS_INVALID;
 422                 goto end;
 423         }
 424
 425         start_session_action = action_start_session_from_action_const(action);
 426
 427         *policy = start_session_action->policy;
 428         status = LTTNG_ACTION_STATUS_OK;
 429 end:
 430         return status;
 431 }
 432
 433 static const struct lttng_rate_policy *
 434 lttng_action_start_session_internal_get_rate_policy(
 435                 const struct lttng_action *action)
 436 {
 437         const struct lttng_action_start_session *_action;
 438         _action = action_start_session_from_action_const(action);
 439
 440         return _action->policy;
 441 }