tests/lib/test_trace_ir_ref.c

   1 /*
   2  * test_trace_ir_ref.c
   3  *
   4  * Trace IR Reference Count test
   5  *
   6  * Copyright 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; under version 2 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  */
  21
  22 #include "tap/tap.h"
  23 #include <babeltrace2/babeltrace.h>
  24 #include <babeltrace2/object-internal.h>
  25 #include <babeltrace2/compat/stdlib-internal.h>
  26 #include <babeltrace2/assert-internal.h>
  27 #include "common.h"
  28
  29 #define NR_TESTS 37
  30
  31 struct user {
  32         bt_trace_class *tc;
  33         bt_stream_class *sc;
  34         bt_event_class *ec;
  35         bt_stream *stream;
  36         bt_event *event;
  37 };
  38
  39 struct writer_user {
  40         struct bt_ctf_writer *writer;
  41         struct bt_ctf_trace *tc;
  42         struct bt_ctf_stream_class *sc;
  43         struct bt_ctf_event_class *ec;
  44         struct bt_ctf_stream *stream;
  45         struct bt_ctf_event *event;
  46 };
  47
  48 const char *writer_user_names[] = {
  49         "writer",
  50         "trace",
  51         "stream class",
  52         "event class",
  53         "stream",
  54         "event",
  55 };
  56
  57 static const size_t WRITER_USER_NR_ELEMENTS =
  58         sizeof(struct writer_user) / sizeof(void *);
  59
  60 /**
  61  * Returns a structure containing the following fields:
  62  *     - uint8_t payload_8;
  63  *     - uint16_t payload_16;
  64  *     - uint32_t payload_32;
  65  */
  66 static bt_field_class *create_integer_struct(bt_trace_class *trace_class)
  67 {
  68         int ret;
  69         bt_field_class *structure = NULL;
  70         bt_field_class *ui8 = NULL, *ui16 = NULL, *ui32 = NULL;
  71
  72         structure = bt_field_class_structure_create(trace_class);
  73         BT_ASSERT(structure);
  74         ui8 = bt_field_class_unsigned_integer_create(trace_class);
  75         BT_ASSERT(ui8);
  76         bt_field_class_integer_set_field_value_range(ui8, 8);
  77         ret = bt_field_class_structure_append_member(structure,
  78                 "payload_8", ui8);
  79         BT_ASSERT(ret == 0);
  80         ui16 = bt_field_class_unsigned_integer_create(trace_class);
  81         BT_ASSERT(ui16);
  82         bt_field_class_integer_set_field_value_range(ui16, 16);
  83         ret = bt_field_class_structure_append_member(structure,
  84                 "payload_16", ui16);
  85         BT_ASSERT(ret == 0);
  86         ui32 = bt_field_class_unsigned_integer_create(trace_class);
  87         BT_ASSERT(ui32);
  88         bt_field_class_integer_set_field_value_range(ui32, 32);
  89         ret = bt_field_class_structure_append_member(structure,
  90                 "payload_32", ui32);
  91         BT_ASSERT(ret == 0);
  92         BT_FIELD_CLASS_PUT_REF_AND_RESET(ui8);
  93         BT_FIELD_CLASS_PUT_REF_AND_RESET(ui16);
  94         BT_FIELD_CLASS_PUT_REF_AND_RESET(ui32);
  95         return structure;
  96 }
  97
  98 static struct bt_ctf_field_type *create_writer_integer_struct(void)
  99 {
 100         int ret;
 101         struct bt_ctf_field_type *structure = NULL;
 102         struct bt_ctf_field_type *ui8 = NULL, *ui16 = NULL, *ui32 = NULL;
 103
 104         structure = bt_ctf_field_type_structure_create();
 105         BT_ASSERT(structure);
 106         ui8 = bt_ctf_field_type_integer_create(8);
 107         BT_ASSERT(ui8);
 108         ret = bt_ctf_field_type_structure_add_field(structure, ui8,
 109                         "payload_8");
 110         BT_ASSERT(ret == 0);
 111         ui16 = bt_ctf_field_type_integer_create(16);
 112         BT_ASSERT(ui16);
 113         ret = bt_ctf_field_type_structure_add_field(structure, ui16,
 114                         "payload_16");
 115         BT_ASSERT(ret == 0);
 116         ui32 = bt_ctf_field_type_integer_create(32);
 117         BT_ASSERT(ui32);
 118         ret = bt_ctf_field_type_structure_add_field(structure, ui32,
 119                         "payload_32");
 120         BT_ASSERT(ret == 0);
 121         BT_OBJECT_PUT_REF_AND_RESET(ui8);
 122         BT_OBJECT_PUT_REF_AND_RESET(ui16);
 123         BT_OBJECT_PUT_REF_AND_RESET(ui32);
 124         return structure;
 125 }
 126
 127 /**
 128  * A simple event has the following payload:
 129  *     - uint8_t payload_8;
 130  *     - uint16_t payload_16;
 131  *     - uint32_t payload_32;
 132  */
 133 static bt_event_class *create_simple_event(
 134                 bt_stream_class *sc, const char *name)
 135 {
 136         int ret;
 137         bt_event_class *event = NULL;
 138         bt_field_class *payload = NULL;
 139
 140         BT_ASSERT(name);
 141         event = bt_event_class_create(sc);
 142         BT_ASSERT(event);
 143         ret = bt_event_class_set_name(event, name);
 144         BT_ASSERT(ret == 0);
 145         payload = create_integer_struct(bt_stream_class_borrow_trace_class(sc));
 146         BT_ASSERT(payload);
 147         ret = bt_event_class_set_payload_field_class(event, payload);
 148         BT_ASSERT(ret == 0);
 149         BT_FIELD_CLASS_PUT_REF_AND_RESET(payload);
 150         return event;
 151 }
 152
 153 /**
 154  * A complex event has the following payload:
 155  *     - uint8_t payload_8;
 156  *     - uint16_t payload_16;
 157  *     - uint32_t payload_32;
 158  *     - struct payload_struct:
 159  *           - uint8_t payload_8;
 160  *           - uint16_t payload_16;
 161  *           - uint32_t payload_32;
 162  */
 163 static bt_event_class *create_complex_event(bt_stream_class *sc,
 164                 const char *name)
 165 {
 166         int ret;
 167         bt_event_class *event = NULL;
 168         bt_field_class *inner = NULL, *outer = NULL;
 169         bt_trace_class *trace_class = bt_stream_class_borrow_trace_class(sc);
 170
 171         BT_ASSERT(name);
 172         event = bt_event_class_create(sc);
 173         BT_ASSERT(event);
 174         ret = bt_event_class_set_name(event, name);
 175         BT_ASSERT(ret == 0);
 176         outer = create_integer_struct(trace_class);
 177         BT_ASSERT(outer);
 178         inner = create_integer_struct(trace_class);
 179         BT_ASSERT(inner);
 180         ret = bt_field_class_structure_append_member(outer,
 181                 "payload_struct", inner);
 182         BT_ASSERT(ret == 0);
 183         ret = bt_event_class_set_payload_field_class(event, outer);
 184         BT_ASSERT(ret == 0);
 185         BT_FIELD_CLASS_PUT_REF_AND_RESET(inner);
 186         BT_FIELD_CLASS_PUT_REF_AND_RESET(outer);
 187         return event;
 188 }
 189
 190 static void set_stream_class_field_classes(
 191                 bt_stream_class *stream_class)
 192 {
 193         bt_trace_class *trace_class =
 194                 bt_stream_class_borrow_trace_class(stream_class);
 195         bt_field_class *packet_context_type;
 196         bt_field_class *fc;
 197         int ret;
 198
 199         packet_context_type = bt_field_class_structure_create(trace_class);
 200         BT_ASSERT(packet_context_type);
 201         fc = bt_field_class_unsigned_integer_create(trace_class);
 202         BT_ASSERT(fc);
 203         bt_field_class_integer_set_field_value_range(fc, 32);
 204         ret = bt_field_class_structure_append_member(packet_context_type,
 205                 "packet_size", fc);
 206         BT_ASSERT(ret == 0);
 207         bt_field_class_put_ref(fc);
 208         fc = bt_field_class_unsigned_integer_create(trace_class);
 209         BT_ASSERT(fc);
 210         bt_field_class_integer_set_field_value_range(fc, 32);
 211         ret = bt_field_class_structure_append_member(packet_context_type,
 212                 "content_size", fc);
 213         BT_ASSERT(ret == 0);
 214         bt_field_class_put_ref(fc);
 215         ret = bt_stream_class_set_packet_context_field_class(
 216                 stream_class, packet_context_type);
 217         BT_ASSERT(ret == 0);
 218         bt_field_class_put_ref(packet_context_type);
 219 }
 220
 221 static void create_sc1(bt_trace_class *trace_class)
 222 {
 223         int ret;
 224         bt_event_class *ec1 = NULL, *ec2 = NULL;
 225         bt_stream_class *sc1 = NULL, *ret_stream = NULL;
 226
 227         sc1 = bt_stream_class_create(trace_class);
 228         BT_ASSERT(sc1);
 229         ret = bt_stream_class_set_name(sc1, "sc1");
 230         BT_ASSERT(ret == 0);
 231         set_stream_class_field_classes(sc1);
 232         ec1 = create_complex_event(sc1, "ec1");
 233         BT_ASSERT(ec1);
 234         ec2 = create_simple_event(sc1, "ec2");
 235         BT_ASSERT(ec2);
 236         ret_stream = bt_event_class_borrow_stream_class(ec1);
 237         ok(ret_stream == sc1, "Borrow parent stream SC1 from EC1");
 238         ret_stream = bt_event_class_borrow_stream_class(ec2);
 239         ok(ret_stream == sc1, "Borrow parent stream SC1 from EC2");
 240         BT_EVENT_CLASS_PUT_REF_AND_RESET(ec1);
 241         BT_EVENT_CLASS_PUT_REF_AND_RESET(ec2);
 242         BT_STREAM_CLASS_PUT_REF_AND_RESET(sc1);
 243 }
 244
 245 static void create_sc2(bt_trace_class *trace_class)
 246 {
 247         int ret;
 248         bt_event_class *ec3 = NULL;
 249         bt_stream_class *sc2 = NULL, *ret_stream = NULL;
 250
 251         sc2 = bt_stream_class_create(trace_class);
 252         BT_ASSERT(sc2);
 253         ret = bt_stream_class_set_name(sc2, "sc2");
 254         BT_ASSERT(ret == 0);
 255         set_stream_class_field_classes(sc2);
 256         ec3 = create_simple_event(sc2, "ec3");
 257         ret_stream = bt_event_class_borrow_stream_class(ec3);
 258         ok(ret_stream == sc2, "Borrow parent stream SC2 from EC3");
 259         BT_EVENT_CLASS_PUT_REF_AND_RESET(ec3);
 260         BT_STREAM_CLASS_PUT_REF_AND_RESET(sc2);
 261 }
 262
 263 static bt_trace_class *create_tc1(bt_self_component_source *self_comp)
 264 {
 265         bt_trace_class *tc1 = NULL;
 266
 267         tc1 = bt_trace_class_create(
 268                 bt_self_component_source_as_self_component(self_comp));
 269         BT_ASSERT(tc1);
 270         create_sc1(tc1);
 271         create_sc2(tc1);
 272         return tc1;
 273 }
 274
 275 static void init_weak_refs(bt_trace_class *tc,
 276                 bt_trace_class **tc1,
 277                 bt_stream_class **sc1,
 278                 bt_stream_class **sc2,
 279                 bt_event_class **ec1,
 280                 bt_event_class **ec2,
 281                 bt_event_class **ec3)
 282 {
 283         *tc1 = tc;
 284         *sc1 = bt_trace_class_borrow_stream_class_by_index(tc, 0);
 285         *sc2 = bt_trace_class_borrow_stream_class_by_index(tc, 1);
 286         *ec1 = bt_stream_class_borrow_event_class_by_index(*sc1, 0);
 287         *ec2 = bt_stream_class_borrow_event_class_by_index(*sc1, 1);
 288         *ec3 = bt_stream_class_borrow_event_class_by_index(*sc2, 0);
 289 }
 290
 291 static void test_example_scenario(bt_self_component_source *self_comp)
 292 {
 293         /*
 294          * Weak pointers to trace IR objects are to be used very
 295          * carefully. This is NOT a good practice and is strongly
 296          * discouraged; this is only done to facilitate the validation
 297          * of expected reference counts without affecting them by taking
 298          * "real" references to the objects.
 299          */
 300         bt_trace_class *tc1 = NULL, *weak_tc1 = NULL;
 301         bt_stream_class *weak_sc1 = NULL, *weak_sc2 = NULL;
 302         bt_event_class *weak_ec1 = NULL, *weak_ec2 = NULL,
 303                         *weak_ec3 = NULL;
 304         struct user user_a = { 0 }, user_b = { 0 }, user_c = { 0 };
 305
 306         /* The only reference which exists at this point is on TC1. */
 307         tc1 = create_tc1(self_comp);
 308         ok(tc1, "Initialize trace");
 309         BT_ASSERT(tc1);
 310         init_weak_refs(tc1, &weak_tc1, &weak_sc1, &weak_sc2, &weak_ec1,
 311                         &weak_ec2, &weak_ec3);
 312         ok(bt_object_get_ref_count((void *) weak_sc1) == 0,
 313                         "Initial SC1 reference count is 0");
 314         ok(bt_object_get_ref_count((void *) weak_sc2) == 0,
 315                         "Initial SC2 reference count is 0");
 316         ok(bt_object_get_ref_count((void *) weak_ec1) == 0,
 317                         "Initial EC1 reference count is 0");
 318         ok(bt_object_get_ref_count((void *) weak_ec2) == 0,
 319                         "Initial EC2 reference count is 0");
 320         ok(bt_object_get_ref_count((void *) weak_ec3) == 0,
 321                         "Initial EC3 reference count is 0");
 322
 323         /* User A has ownership of the trace. */
 324         BT_OBJECT_MOVE_REF(user_a.tc, tc1);
 325         ok(bt_object_get_ref_count((void *) user_a.tc) == 1,
 326                         "TC1 reference count is 1");
 327
 328         /* User A acquires a reference to SC2 from TC1. */
 329         user_a.sc = bt_trace_class_borrow_stream_class_by_index(
 330                         user_a.tc, 1);
 331         bt_stream_class_get_ref(user_a.sc);
 332         ok(user_a.sc, "User A acquires SC2 from TC1");
 333         ok(bt_object_get_ref_count((void *) weak_tc1) == 2,
 334                         "TC1 reference count is 2");
 335         ok(bt_object_get_ref_count((void *) weak_sc2) == 1,
 336                         "SC2 reference count is 1");
 337
 338         /* User A acquires a reference to EC3 from SC2. */
 339         user_a.ec = bt_stream_class_borrow_event_class_by_index(
 340                         user_a.sc, 0);
 341         bt_event_class_get_ref(user_a.ec);
 342         ok(user_a.ec, "User A acquires EC3 from SC2");
 343         ok(bt_object_get_ref_count((void *) weak_tc1) == 2,
 344                         "TC1 reference count is 2");
 345         ok(bt_object_get_ref_count((void *) weak_sc2) == 2,
 346                         "SC2 reference count is 2");
 347         ok(bt_object_get_ref_count((void *) weak_ec3) == 1,
 348                         "EC3 reference count is 1");
 349
 350         /* User A releases its reference to SC2. */
 351         diag("User A releases SC2");
 352         BT_STREAM_CLASS_PUT_REF_AND_RESET(user_a.sc);
 353         /*
 354          * We keep the pointer to SC2 around to validate its reference
 355          * count.
 356          */
 357         ok(bt_object_get_ref_count((void *) weak_tc1) == 2,
 358                         "TC1 reference count is 2");
 359         ok(bt_object_get_ref_count((void *) weak_sc2) == 1,
 360                         "SC2 reference count is 1");
 361         ok(bt_object_get_ref_count((void *) weak_ec3) == 1,
 362                         "EC3 reference count is 1");
 363
 364         /* User A releases its reference to TC1. */
 365         diag("User A releases TC1");
 366         BT_TRACE_CLASS_PUT_REF_AND_RESET(user_a.tc);
 367         /*
 368          * We keep the pointer to TC1 around to validate its reference
 369          * count.
 370          */
 371         ok(bt_object_get_ref_count((void *) weak_tc1) == 1,
 372                         "TC1 reference count is 1");
 373         ok(bt_object_get_ref_count((void *) weak_sc2) == 1,
 374                         "SC2 reference count is 1");
 375         ok(bt_object_get_ref_count((void *) weak_ec3) == 1,
 376                         "EC3 reference count is 1");
 377
 378         /* User B acquires a reference to SC1. */
 379         diag("User B acquires a reference to SC1");
 380         user_b.sc = weak_sc1;
 381         bt_stream_class_get_ref(user_b.sc);
 382         ok(bt_object_get_ref_count((void *) weak_tc1) == 2,
 383                         "TC1 reference count is 2");
 384         ok(bt_object_get_ref_count((void *) weak_sc1) == 1,
 385                         "SC1 reference count is 1");
 386
 387         /* User C acquires a reference to EC1. */
 388         diag("User C acquires a reference to EC1");
 389         user_c.ec = bt_stream_class_borrow_event_class_by_index(
 390                         user_b.sc, 0);
 391         bt_event_class_get_ref(user_c.ec);
 392         ok(bt_object_get_ref_count((void *) weak_ec1) == 1,
 393                         "EC1 reference count is 1");
 394         ok(bt_object_get_ref_count((void *) weak_sc1) == 2,
 395                         "SC1 reference count is 2");
 396
 397         /* User A releases its reference on EC3. */
 398         diag("User A releases its reference on EC3");
 399         BT_EVENT_CLASS_PUT_REF_AND_RESET(user_a.ec);
 400         ok(bt_object_get_ref_count((void *) weak_ec3) == 0,
 401                         "EC3 reference count is 1");
 402         ok(bt_object_get_ref_count((void *) weak_sc2) == 0,
 403                         "SC2 reference count is 0");
 404         ok(bt_object_get_ref_count((void *) weak_tc1) == 1,
 405                         "TC1 reference count is 1");
 406
 407         /* User B releases its reference on SC1. */
 408         diag("User B releases its reference on SC1");
 409         BT_STREAM_CLASS_PUT_REF_AND_RESET(user_b.sc);
 410         ok(bt_object_get_ref_count((void *) weak_sc1) == 1,
 411                         "SC1 reference count is 1");
 412
 413         /*
 414          * User C is the sole owner of an object and is keeping the whole
 415          * trace hierarchy "alive" by holding a reference to EC1.
 416          */
 417         ok(bt_object_get_ref_count((void *) weak_tc1) == 1,
 418                         "TC1 reference count is 1");
 419         ok(bt_object_get_ref_count((void *) weak_sc1) == 1,
 420                         "SC1 reference count is 1");
 421         ok(bt_object_get_ref_count((void *) weak_sc2) == 0,
 422                         "SC2 reference count is 0");
 423         ok(bt_object_get_ref_count((void *) weak_ec1) == 1,
 424                         "EC1 reference count is 1");
 425         ok(bt_object_get_ref_count((void *) weak_ec2) == 0,
 426                         "EC2 reference count is 0");
 427         ok(bt_object_get_ref_count((void *) weak_ec3) == 0,
 428                         "EC3 reference count is 0");
 429
 430         /* Reclaim last reference held by User C. */
 431         BT_EVENT_CLASS_PUT_REF_AND_RESET(user_c.ec);
 432 }
 433
 434 static
 435 bt_self_component_status src_init(
 436         bt_self_component_source *self_comp,
 437         const bt_value *params, void *init_method_data)
 438 {
 439         test_example_scenario(self_comp);
 440         return BT_SELF_COMPONENT_STATUS_OK;
 441 }
 442
 443 static
 444 bt_self_message_iterator_status src_iter_next(
 445                 bt_self_message_iterator *self_iterator,
 446                 bt_message_array_const msgs, uint64_t capacity,
 447                 uint64_t *count)
 448 {
 449         return BT_SELF_MESSAGE_ITERATOR_STATUS_ERROR;
 450 }
 451
 452 static void test_example_scenario_in_graph(void)
 453 {
 454         bt_component_class_source *comp_cls;
 455         bt_graph *graph;
 456         int ret;
 457
 458         comp_cls = bt_component_class_source_create("src", src_iter_next);
 459         BT_ASSERT(comp_cls);
 460         ret = bt_component_class_source_set_init_method(comp_cls, src_init);
 461         BT_ASSERT(ret == 0);
 462         graph = bt_graph_create();
 463         ret = bt_graph_add_source_component(graph, comp_cls, "src-comp",
 464                 NULL, NULL);
 465         BT_ASSERT(ret == 0);
 466         bt_graph_put_ref(graph);
 467         bt_component_class_source_put_ref(comp_cls);
 468 }
 469
 470 static void create_writer_user_full(struct writer_user *user)
 471 {
 472         gchar *trace_path;
 473         struct bt_ctf_field_type *ft;
 474         struct bt_ctf_field *field;
 475         struct bt_ctf_clock *clock;
 476         int ret;
 477
 478         trace_path = g_build_filename(g_get_tmp_dir(), "ctfwriter_XXXXXX", NULL);
 479         if (!bt_mkdtemp(trace_path)) {
 480                 perror("# perror");
 481         }
 482
 483         user->writer = bt_ctf_writer_create(trace_path);
 484         BT_ASSERT(user->writer);
 485         ret = bt_ctf_writer_set_byte_order(user->writer,
 486                 BT_CTF_BYTE_ORDER_LITTLE_ENDIAN);
 487         BT_ASSERT(ret == 0);
 488         user->tc = bt_ctf_writer_get_trace(user->writer);
 489         BT_ASSERT(user->tc);
 490         user->sc = bt_ctf_stream_class_create("sc");
 491         BT_ASSERT(user->sc);
 492         clock = bt_ctf_clock_create("the_clock");
 493         BT_ASSERT(clock);
 494         ret = bt_ctf_writer_add_clock(user->writer, clock);
 495         BT_ASSERT(!ret);
 496         ret = bt_ctf_stream_class_set_clock(user->sc, clock);
 497         BT_ASSERT(!ret);
 498         BT_OBJECT_PUT_REF_AND_RESET(clock);
 499         user->stream = bt_ctf_writer_create_stream(user->writer, user->sc);
 500         BT_ASSERT(user->stream);
 501         user->ec = bt_ctf_event_class_create("ec");
 502         BT_ASSERT(user->ec);
 503         ft = create_writer_integer_struct();
 504         BT_ASSERT(ft);
 505         ret = bt_ctf_event_class_set_payload_field_type(user->ec, ft);
 506         BT_OBJECT_PUT_REF_AND_RESET(ft);
 507         BT_ASSERT(!ret);
 508         ret = bt_ctf_stream_class_add_event_class(user->sc, user->ec);
 509         BT_ASSERT(!ret);
 510         user->event = bt_ctf_event_create(user->ec);
 511         BT_ASSERT(user->event);
 512         field = bt_ctf_event_get_payload(user->event, "payload_8");
 513         BT_ASSERT(field);
 514         ret = bt_ctf_field_integer_unsigned_set_value(field, 10);
 515         BT_ASSERT(!ret);
 516         BT_OBJECT_PUT_REF_AND_RESET(field);
 517         field = bt_ctf_event_get_payload(user->event, "payload_16");
 518         BT_ASSERT(field);
 519         ret = bt_ctf_field_integer_unsigned_set_value(field, 20);
 520         BT_ASSERT(!ret);
 521         BT_OBJECT_PUT_REF_AND_RESET(field);
 522         field = bt_ctf_event_get_payload(user->event, "payload_32");
 523         BT_ASSERT(field);
 524         ret = bt_ctf_field_integer_unsigned_set_value(field, 30);
 525         BT_ASSERT(!ret);
 526         BT_OBJECT_PUT_REF_AND_RESET(field);
 527         ret = bt_ctf_stream_append_event(user->stream, user->event);
 528         BT_ASSERT(!ret);
 529         recursive_rmdir(trace_path);
 530         g_free(trace_path);
 531 }
 532
 533 static void test_put_order_swap(size_t *array, size_t a, size_t b)
 534 {
 535         size_t temp = array[a];
 536
 537         array[a] = array[b];
 538         array[b] = temp;
 539 }
 540
 541 static void test_put_order_put_objects(size_t *array, size_t size)
 542 {
 543         size_t i;
 544         struct writer_user user = { 0 };
 545         void **objects = (void *) &user;
 546
 547         create_writer_user_full(&user);
 548         printf("# ");
 549
 550         for (i = 0; i < size; ++i) {
 551                 void *obj = objects[array[i]];
 552
 553                 printf("%s", writer_user_names[array[i]]);
 554                 BT_OBJECT_PUT_REF_AND_RESET(obj);
 555
 556                 if (i < size - 1) {
 557                         printf(" -> ");
 558                 }
 559         }
 560
 561         puts("");
 562 }
 563
 564 static void test_put_order_permute(size_t *array, int k, size_t size)
 565 {
 566         if (k == 0) {
 567                 test_put_order_put_objects(array, size);
 568         } else {
 569                 int i;
 570
 571                 for (i = k - 1; i >= 0; i--) {
 572                         size_t next_k = k - 1;
 573
 574                         test_put_order_swap(array, i, next_k);
 575                         test_put_order_permute(array, next_k, size);
 576                         test_put_order_swap(array, i, next_k);
 577                 }
 578         }
 579 }
 580
 581 static void test_put_order(void)
 582 {
 583         size_t i;
 584         size_t array[WRITER_USER_NR_ELEMENTS];
 585
 586         /* Initialize array of indexes */
 587         for (i = 0; i < WRITER_USER_NR_ELEMENTS; ++i) {
 588                 array[i] = i;
 589         }
 590
 591         test_put_order_permute(array, WRITER_USER_NR_ELEMENTS,
 592                 WRITER_USER_NR_ELEMENTS);
 593 }
 594
 595 /**
 596  * The objective of this test is to implement and expand upon the scenario
 597  * described in the reference counting documentation and ensure that any node of
 598  * the Trace, Stream Class, Event Class, Stream and Event hiearchy keeps all
 599  * other "alive" and reachable.
 600  *
 601  * External tools (e.g. valgrind) should be used to confirm that this
 602  * known-good test does not leak memory.
 603  */
 604 int main(int argc, char **argv)
 605 {
 606         /* Initialize tap harness before any tests */
 607         plan_tests(NR_TESTS);
 608
 609         test_example_scenario_in_graph();
 610         test_put_order();
 611
 612         return exit_status();
 613 }