malloc/tst-dynarray.c

   1 /* Test for dynamic arrays.
   2    Copyright (C) 2017-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include "tst-dynarray-shared.h"
  20
  21 #include <errno.h>
  22 #include <stdint.h>
  23 #include <libc-diag.h>
  24
  25 #define DYNARRAY_STRUCT dynarray_long
  26 #define DYNARRAY_ELEMENT long
  27 #define DYNARRAY_PREFIX dynarray_long_
  28 #define DYNARRAY_ELEMENT_INIT(e) (*(e) = 17)
  29 #include <malloc/dynarray-skeleton.c>
  30
  31 struct long_array
  32 {
  33   long *array;
  34   size_t length;
  35 };
  36
  37 #define DYNARRAY_STRUCT dynarray_long_noscratch
  38 #define DYNARRAY_ELEMENT long
  39 #define DYNARRAY_PREFIX dynarray_long_noscratch_
  40 #define DYNARRAY_ELEMENT_INIT(e) (*(e) = 23)
  41 #define DYNARRAY_FINAL_TYPE struct long_array
  42 #define DYNARRAY_INITIAL_SIZE 0
  43 #include <malloc/dynarray-skeleton.c>
  44
  45 #define DYNARRAY_STRUCT zstr
  46 #define DYNARRAY_ELEMENT char
  47 #define DYNARRAY_PREFIX zstr_
  48 #define DYNARRAY_INITIAL_SIZE 128
  49 #include <malloc/dynarray-skeleton.c>
  50
  51 #include <malloc.h>
  52 #include <mcheck.h>
  53 #include <stdint.h>
  54 #include <support/check.h>
  55 #include <support/support.h>
  56
  57 enum { max_count = 20 };
  58
  59 /* Test dynamic arrays with int elements (no automatic deallocation
  60    for elements).  */
  61 static void
  62 test_int (void)
  63 {
  64   /* Empty array.  */
  65   {
  66     struct dynarray_int dyn;
  67     dynarray_int_init (&dyn);
  68     CHECK_EMPTY (int, &dyn);
  69   }
  70
  71   /* Empty array with finalization.  */
  72   {
  73     struct dynarray_int dyn;
  74     dynarray_int_init (&dyn);
  75     CHECK_INIT_STATE (int, &dyn);
  76     struct int_array result = { (int *) (uintptr_t) -1, -1 };
  77     TEST_VERIFY_EXIT (dynarray_int_finalize (&dyn, &result));
  78     CHECK_INIT_STATE (int, &dyn);
  79     TEST_VERIFY_EXIT (result.array == NULL);
  80     TEST_VERIFY_EXIT (result.length == 0);
  81   }
  82
  83   /* Non-empty array tests.
  84
  85      do_add: Switch between emplace (false) and add (true).
  86      do_finalize: Perform finalize call at the end.
  87      do_clear: Perform clear call at the end.
  88      do_remove_last: Perform remove_last call after adding elements.
  89      count: Number of elements added to the array.  */
  90   for (int do_add = 0; do_add < 2; ++do_add)
  91     for (int do_finalize = 0; do_finalize < 2; ++do_finalize)
  92       for (int do_clear = 0; do_clear < 2; ++do_clear)
  93         for (int do_remove_last = 0; do_remove_last < 2; ++do_remove_last)
  94           for (unsigned int count = 0; count < max_count; ++count)
  95             {
  96               if (do_remove_last && count == 0)
  97                 continue;
  98               unsigned int base = count * count;
  99               struct dynarray_int dyn;
 100               dynarray_int_init (&dyn);
 101               for (unsigned int i = 0; i < count; ++i)
 102                 {
 103                   if (do_add)
 104                     dynarray_int_add (&dyn, base + i);
 105                   else
 106                     {
 107                       int *place = dynarray_int_emplace (&dyn);
 108                       TEST_VERIFY_EXIT (place != NULL);
 109                       *place = base + i;
 110                     }
 111                   TEST_VERIFY_EXIT (!dynarray_int_has_failed (&dyn));
 112                   TEST_VERIFY_EXIT (dynarray_int_size (&dyn) == i + 1);
 113                   TEST_VERIFY_EXIT (dynarray_int_size (&dyn)
 114                                     <= dyn.u.dynarray_header.allocated);
 115                 }
 116               TEST_VERIFY_EXIT (dynarray_int_size (&dyn) == count);
 117               TEST_VERIFY_EXIT (count <= dyn.u.dynarray_header.allocated);
 118               if (count > 0)
 119                 {
 120                   TEST_VERIFY (dynarray_int_begin (&dyn)
 121                                == dynarray_int_at (&dyn, 0));
 122                   TEST_VERIFY (dynarray_int_end (&dyn)
 123                                == dynarray_int_at (&dyn, count - 1) + 1);
 124                 }
 125               unsigned final_count;
 126               bool heap_array = dyn.u.dynarray_header.array != dyn.scratch;
 127               if (do_remove_last)
 128                 {
 129                   dynarray_int_remove_last (&dyn);
 130                   if (count == 0)
 131                     final_count = 0;
 132                   else
 133                     final_count = count - 1;
 134                 }
 135               else
 136                 final_count = count;
 137               if (final_count > 0)
 138                 {
 139                   TEST_VERIFY (dynarray_int_begin (&dyn)
 140                                == dynarray_int_at (&dyn, 0));
 141                   TEST_VERIFY (dynarray_int_end (&dyn)
 142                                == dynarray_int_at (&dyn, final_count - 1) + 1);
 143                 }
 144               if (do_clear)
 145                 {
 146                   dynarray_int_clear (&dyn);
 147                   final_count = 0;
 148                 }
 149               TEST_VERIFY_EXIT (!dynarray_int_has_failed (&dyn));
 150               TEST_VERIFY_EXIT ((dyn.u.dynarray_header.array != dyn.scratch)
 151                                 == heap_array);
 152               TEST_VERIFY_EXIT (dynarray_int_size (&dyn) == final_count);
 153               TEST_VERIFY_EXIT (dyn.u.dynarray_header.allocated
 154                                 >= final_count);
 155               if (!do_clear)
 156                 for (unsigned int i = 0; i < final_count; ++i)
 157                   TEST_VERIFY_EXIT (*dynarray_int_at (&dyn, i) == base + i);
 158               if (do_finalize)
 159                 {
 160                   struct int_array result = { (int *) (uintptr_t) -1, -1 };
 161                   TEST_VERIFY_EXIT (dynarray_int_finalize (&dyn, &result));
 162                   CHECK_INIT_STATE (int, &dyn);
 163                   TEST_VERIFY_EXIT (result.length == final_count);
 164                   if (final_count == 0)
 165                     TEST_VERIFY_EXIT (result.array == NULL);
 166                   else
 167                     {
 168                       TEST_VERIFY_EXIT (result.array != NULL);
 169                       TEST_VERIFY_EXIT (result.array != (int *) (uintptr_t) -1);
 170                       TEST_VERIFY_EXIT
 171                         (malloc_usable_size (result.array)
 172                          >= final_count * sizeof (result.array[0]));
 173                       for (unsigned int i = 0; i < final_count; ++i)
 174                         TEST_VERIFY_EXIT (result.array[i] == base + i);
 175                       free (result.array);
 176                     }
 177                 }
 178               else /* !do_finalize */
 179                 {
 180                   dynarray_int_free (&dyn);
 181                   CHECK_INIT_STATE (int, &dyn);
 182                 }
 183             }
 184 }
 185
 186 /* Test dynamic arrays with char * elements (with automatic
 187    deallocation of the pointed-to strings).  */
 188 static void
 189 test_str (void)
 190 {
 191   /* Empty array.  */
 192   {
 193     struct dynarray_str dyn;
 194     dynarray_str_init (&dyn);
 195     CHECK_EMPTY (str, &dyn);
 196   }
 197
 198   /* Empty array with finalization.  */
 199   {
 200     struct dynarray_str dyn;
 201     dynarray_str_init (&dyn);
 202     TEST_VERIFY_EXIT (!dynarray_str_has_failed (&dyn));
 203     struct str_array result = { (char **) (uintptr_t) -1, -1 };
 204     TEST_VERIFY_EXIT (dynarray_str_finalize (&dyn, &result));
 205     CHECK_INIT_STATE (str, &dyn);
 206     TEST_VERIFY_EXIT (result.array == NULL);
 207     TEST_VERIFY_EXIT (result.length == 0);
 208   }
 209
 210   /* Non-empty array tests.
 211
 212      do_add: Switch between emplace (false) and add (true).
 213      do_finalize: Perform finalize call at the end.
 214      do_clear: Perform clear call at the end.
 215      do_remove_last: Perform remove_last call after adding elements.
 216      count: Number of elements added to the array.  */
 217   for (int do_add = 0; do_add < 2; ++do_add)
 218     for (int do_finalize = 0; do_finalize < 2; ++do_finalize)
 219       for (int do_clear = 0; do_clear < 2; ++do_clear)
 220         for (int do_remove_last = 0; do_remove_last < 2; ++do_remove_last)
 221           for (unsigned int count = 0; count < max_count; ++count)
 222             {
 223               if (do_remove_last && count == 0)
 224                 continue;
 225               unsigned int base = count * count;
 226               struct dynarray_str dyn;
 227               dynarray_str_init (&dyn);
 228               for (unsigned int i = 0; i < count; ++i)
 229                 {
 230                   char *item = xasprintf ("%d", base + i);
 231                   if (do_add)
 232                     dynarray_str_add (&dyn, item);
 233                   else
 234                     {
 235                       char **place = dynarray_str_emplace (&dyn);
 236                       TEST_VERIFY_EXIT (place != NULL);
 237                       TEST_VERIFY_EXIT (*place == NULL);
 238                       *place = item;
 239                     }
 240                   TEST_VERIFY_EXIT (!dynarray_str_has_failed (&dyn));
 241                   TEST_VERIFY_EXIT (dynarray_str_size (&dyn) == i + 1);
 242                   TEST_VERIFY_EXIT (dynarray_str_size (&dyn)
 243                                     <= dyn.u.dynarray_header.allocated);
 244                 }
 245               TEST_VERIFY_EXIT (dynarray_str_size (&dyn) == count);
 246               TEST_VERIFY_EXIT (count <= dyn.u.dynarray_header.allocated);
 247               if (count > 0)
 248                 {
 249                   TEST_VERIFY (dynarray_str_begin (&dyn)
 250                                == dynarray_str_at (&dyn, 0));
 251                   TEST_VERIFY (dynarray_str_end (&dyn)
 252                                == dynarray_str_at (&dyn, count - 1) + 1);
 253                 }
 254               unsigned final_count;
 255               bool heap_array = dyn.u.dynarray_header.array != dyn.scratch;
 256               if (do_remove_last)
 257                 {
 258                   dynarray_str_remove_last (&dyn);
 259                   if (count == 0)
 260                     final_count = 0;
 261                   else
 262                     final_count = count - 1;
 263                 }
 264               else
 265                 final_count = count;
 266               if (final_count > 0)
 267                 {
 268                   TEST_VERIFY (dynarray_str_begin (&dyn)
 269                                == dynarray_str_at (&dyn, 0));
 270                   TEST_VERIFY (dynarray_str_end (&dyn)
 271                                == dynarray_str_at (&dyn, final_count - 1) + 1);
 272                 }
 273               if (do_clear)
 274                 {
 275                   dynarray_str_clear (&dyn);
 276                   final_count = 0;
 277                 }
 278               TEST_VERIFY_EXIT (!dynarray_str_has_failed (&dyn));
 279               TEST_VERIFY_EXIT ((dyn.u.dynarray_header.array != dyn.scratch)
 280                                 == heap_array);
 281               TEST_VERIFY_EXIT (dynarray_str_size (&dyn) == final_count);
 282               TEST_VERIFY_EXIT (dyn.u.dynarray_header.allocated
 283                                 >= final_count);
 284               if (!do_clear)
 285                 for (unsigned int i = 0; i < count - do_remove_last; ++i)
 286                   {
 287                     char *expected = xasprintf ("%d", base + i);
 288                     const char *actual = *dynarray_str_at (&dyn, i);
 289                     TEST_VERIFY_EXIT (strcmp (actual, expected) == 0);
 290                     free (expected);
 291                   }
 292               if (do_finalize)
 293                 {
 294                   struct str_array result = { (char **) (uintptr_t) -1, -1 };
 295                   TEST_VERIFY_EXIT (dynarray_str_finalize (&dyn, &result));
 296                   CHECK_INIT_STATE (str, &dyn);
 297                   TEST_VERIFY_EXIT (result.length == final_count);
 298                   if (final_count == 0)
 299                     TEST_VERIFY_EXIT (result.array == NULL);
 300                   else
 301                     {
 302                       TEST_VERIFY_EXIT (result.array != NULL);
 303                       TEST_VERIFY_EXIT (result.array
 304                                         != (char **) (uintptr_t) -1);
 305                       TEST_VERIFY_EXIT (result.length
 306                                         == count - do_remove_last);
 307                       TEST_VERIFY_EXIT
 308                         (malloc_usable_size (result.array)
 309                          >= final_count * sizeof (result.array[0]));
 310                       for (unsigned int i = 0; i < count - do_remove_last; ++i)
 311                         {
 312                           char *expected = xasprintf ("%d", base + i);
 313                           char *actual = result.array[i];
 314                           TEST_VERIFY_EXIT (strcmp (actual, expected) == 0);
 315                           free (expected);
 316                           free (actual);
 317                         }
 318                       free (result.array);
 319                     }
 320                 }
 321               else /* !do_finalize */
 322                 {
 323                   dynarray_str_free (&dyn);
 324                   CHECK_INIT_STATE (str, &dyn);
 325                 }
 326             }
 327
 328   /* Test resizing.  */
 329   {
 330     enum { count = 2131 };
 331     struct dynarray_str dyn;
 332     dynarray_str_init (&dyn);
 333
 334     /* From length 0 to length 1.  */
 335     TEST_VERIFY (dynarray_str_resize (&dyn, 1));
 336     TEST_VERIFY (dynarray_str_size (&dyn) == 1);
 337     TEST_VERIFY (*dynarray_str_at (&dyn, 0) == NULL);
 338     *dynarray_str_at (&dyn, 0) = xstrdup ("allocated");
 339     dynarray_str_free (&dyn);
 340
 341     /* From length 0 to length 1 and 2.  */
 342     TEST_VERIFY (dynarray_str_resize (&dyn, 1));
 343     TEST_VERIFY (dynarray_str_size (&dyn) == 1);
 344     TEST_VERIFY (*dynarray_str_at (&dyn, 0) == NULL);
 345     *dynarray_str_at (&dyn, 0) = xstrdup ("allocated0");
 346     TEST_VERIFY (dynarray_str_resize (&dyn, 2));
 347     TEST_VERIFY (dynarray_str_size (&dyn) == 2);
 348     TEST_VERIFY (strcmp (*dynarray_str_at (&dyn, 0), "allocated0") == 0);
 349     TEST_VERIFY (*dynarray_str_at (&dyn, 1) == NULL);
 350     *dynarray_str_at (&dyn, 1) = xstrdup ("allocated1");
 351     TEST_VERIFY (dynarray_str_resize (&dyn, count));
 352     TEST_VERIFY (dynarray_str_size (&dyn) == count);
 353     TEST_VERIFY (strcmp (*dynarray_str_at (&dyn, 0), "allocated0") == 0);
 354     TEST_VERIFY (strcmp (*dynarray_str_at (&dyn, 1), "allocated1") == 0);
 355     for (int i = 2; i < count; ++i)
 356       TEST_VERIFY (*dynarray_str_at (&dyn, i) == NULL);
 357     *dynarray_str_at (&dyn, count - 1) = xstrdup ("allocated2");
 358     TEST_VERIFY (dynarray_str_resize (&dyn, 3));
 359     TEST_VERIFY (strcmp (*dynarray_str_at (&dyn, 0), "allocated0") == 0);
 360     TEST_VERIFY (strcmp (*dynarray_str_at (&dyn, 1), "allocated1") == 0);
 361     TEST_VERIFY (*dynarray_str_at (&dyn, 2) == NULL);
 362     dynarray_str_free (&dyn);
 363   }
 364 }
 365
 366 /* Verify that DYNARRAY_ELEMENT_INIT has an effect.  */
 367 static void
 368 test_long_init (void)
 369 {
 370   enum { count = 2131 };
 371   {
 372     struct dynarray_long dyn;
 373     dynarray_long_init (&dyn);
 374     for (int i = 0; i < count; ++i)
 375       {
 376         long *place = dynarray_long_emplace (&dyn);
 377         TEST_VERIFY_EXIT (place != NULL);
 378         TEST_VERIFY (*place == 17);
 379       }
 380     TEST_VERIFY (dynarray_long_size (&dyn) == count);
 381     for (int i = 0; i < count; ++i)
 382       TEST_VERIFY (*dynarray_long_at (&dyn, i) == 17);
 383     dynarray_long_free (&dyn);
 384
 385     TEST_VERIFY (dynarray_long_resize (&dyn, 1));
 386     TEST_VERIFY (dynarray_long_size (&dyn) == 1);
 387     TEST_VERIFY (*dynarray_long_at (&dyn, 0) == 17);
 388     *dynarray_long_at (&dyn, 0) = 18;
 389     dynarray_long_free (&dyn);
 390     TEST_VERIFY (dynarray_long_resize (&dyn, 1));
 391     TEST_VERIFY (dynarray_long_size (&dyn) == 1);
 392     TEST_VERIFY (*dynarray_long_at (&dyn, 0) == 17);
 393     TEST_VERIFY (dynarray_long_resize (&dyn, 2));
 394     TEST_VERIFY (dynarray_long_size (&dyn) == 2);
 395     TEST_VERIFY (*dynarray_long_at (&dyn, 0) == 17);
 396     TEST_VERIFY (*dynarray_long_at (&dyn, 1) == 17);
 397     *dynarray_long_at (&dyn, 0) = 18;
 398     TEST_VERIFY (dynarray_long_resize (&dyn, count));
 399     TEST_VERIFY (dynarray_long_size (&dyn) == count);
 400     TEST_VERIFY (*dynarray_long_at (&dyn, 0) == 18);
 401     for (int i = 1; i < count; ++i)
 402       TEST_VERIFY (*dynarray_long_at (&dyn, i) == 17);
 403     dynarray_long_free (&dyn);
 404   }
 405
 406   /* Similar, but without an on-stack scratch region
 407      (DYNARRAY_INITIAL_SIZE is 0).  */
 408   {
 409     struct dynarray_long_noscratch dyn;
 410     dynarray_long_noscratch_init (&dyn);
 411     struct long_array result;
 412     TEST_VERIFY_EXIT (dynarray_long_noscratch_finalize (&dyn, &result));
 413     TEST_VERIFY (result.array == NULL);
 414     TEST_VERIFY (result.length == 0);
 415
 416     /* Test with one element.  */
 417     {
 418       long *place = dynarray_long_noscratch_emplace (&dyn);
 419       TEST_VERIFY_EXIT (place != NULL);
 420       TEST_VERIFY (*place == 23);
 421     }
 422     TEST_VERIFY (dynarray_long_noscratch_size (&dyn) == 1);
 423     TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, 0) == 23);
 424     TEST_VERIFY_EXIT (dynarray_long_noscratch_finalize (&dyn, &result));
 425     TEST_VERIFY_EXIT (result.array != NULL);
 426     TEST_VERIFY (result.length == 1);
 427     TEST_VERIFY (result.array[0] == 23);
 428     free (result.array);
 429
 430     for (int i = 0; i < count; ++i)
 431       {
 432         long *place = dynarray_long_noscratch_emplace (&dyn);
 433         TEST_VERIFY_EXIT (place != NULL);
 434         TEST_VERIFY (*place == 23);
 435         if (i == 0)
 436           *place = 29;
 437       }
 438     TEST_VERIFY (dynarray_long_noscratch_size (&dyn) == count);
 439     TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, 0) == 29);
 440     for (int i = 1; i < count; ++i)
 441       TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, i) == 23);
 442     TEST_VERIFY_EXIT (dynarray_long_noscratch_finalize (&dyn, &result));
 443     TEST_VERIFY_EXIT (result.array != NULL);
 444     TEST_VERIFY (result.length == count);
 445     TEST_VERIFY (result.array[0] == 29);
 446     for (int i = 1; i < count; ++i)
 447       TEST_VERIFY (result.array[i] == 23);
 448     free (result.array);
 449
 450     TEST_VERIFY (dynarray_long_noscratch_resize (&dyn, 1));
 451     TEST_VERIFY (dynarray_long_noscratch_size (&dyn) == 1);
 452     TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, 0) == 23);
 453     *dynarray_long_noscratch_at (&dyn, 0) = 24;
 454     dynarray_long_noscratch_free (&dyn);
 455     TEST_VERIFY (dynarray_long_noscratch_resize (&dyn, 1));
 456     TEST_VERIFY (dynarray_long_noscratch_size (&dyn) == 1);
 457     TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, 0) == 23);
 458     TEST_VERIFY (dynarray_long_noscratch_resize (&dyn, 2));
 459     TEST_VERIFY (dynarray_long_noscratch_size (&dyn) == 2);
 460     TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, 0) == 23);
 461     TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, 1) == 23);
 462     *dynarray_long_noscratch_at (&dyn, 0) = 24;
 463     TEST_VERIFY (dynarray_long_noscratch_resize (&dyn, count));
 464     TEST_VERIFY (dynarray_long_noscratch_size (&dyn) == count);
 465     TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, 0) == 24);
 466     for (int i = 1; i < count; ++i)
 467       TEST_VERIFY (*dynarray_long_noscratch_at (&dyn, i) == 23);
 468     dynarray_long_noscratch_free (&dyn);
 469   }
 470 }
 471
 472 /* Test overflow in resize.  */
 473 static void
 474 test_long_overflow (void)
 475 {
 476   {
 477     struct dynarray_long dyn;
 478     dynarray_long_init (&dyn);
 479     errno = EINVAL;
 480     DIAG_PUSH_NEEDS_COMMENT;
 481     /* GCC 12 (on 32-bit platforms) warns that after inlining, a loop
 482        iteration would invoke undefined behavior.  That loop iteration
 483        can never be executed because an allocation of this size must
 484        fail.  */
 485     DIAG_IGNORE_NEEDS_COMMENT (12, "-Waggressive-loop-optimizations");
 486     TEST_VERIFY (!dynarray_long_resize
 487                  (&dyn, (SIZE_MAX / sizeof (long)) + 1));
 488     DIAG_POP_NEEDS_COMMENT;
 489     TEST_VERIFY (errno == ENOMEM);
 490     TEST_VERIFY (dynarray_long_has_failed (&dyn));
 491   }
 492
 493   {
 494     struct dynarray_long_noscratch dyn;
 495     dynarray_long_noscratch_init (&dyn);
 496     errno = EINVAL;
 497     DIAG_PUSH_NEEDS_COMMENT;
 498     /* GCC 12 (on 32-bit platforms) warns that after inlining, a loop
 499        iteration would invoke undefined behavior.  That loop iteration
 500        can never be executed because an allocation of this size must
 501        fail.  */
 502     DIAG_IGNORE_NEEDS_COMMENT (12, "-Waggressive-loop-optimizations");
 503     TEST_VERIFY (!dynarray_long_noscratch_resize
 504                  (&dyn, (SIZE_MAX / sizeof (long)) + 1));
 505     DIAG_POP_NEEDS_COMMENT;
 506     TEST_VERIFY (errno == ENOMEM);
 507     TEST_VERIFY (dynarray_long_noscratch_has_failed (&dyn));
 508   }
 509 }
 510
 511 /* Test NUL-terminated string construction with the add function and
 512    the simple finalize function.  */
 513 static void
 514 test_zstr (void)
 515 {
 516   /* Totally empty string (no NUL termination).  */
 517   {
 518     struct zstr s;
 519     zstr_init (&s);
 520     char *result = zstr_finalize (&s, NULL);
 521     TEST_VERIFY (result == NULL);
 522     TEST_VERIFY (zstr_size (&s) == 0);
 523     size_t length = 1;
 524     result = zstr_finalize (&s, &length);
 525     TEST_VERIFY (result == NULL);
 526     TEST_VERIFY (length == 0);
 527     TEST_VERIFY (zstr_size (&s) == 0);
 528   }
 529
 530   /* Empty string.  */
 531   {
 532     struct zstr s;
 533     zstr_init (&s);
 534     zstr_add (&s, '\0');
 535     char *result = zstr_finalize (&s, NULL);
 536     TEST_VERIFY_EXIT (result != NULL);
 537     TEST_VERIFY (*result == '\0');
 538     TEST_VERIFY (zstr_size (&s) == 0);
 539     free (result);
 540
 541     zstr_add (&s, '\0');
 542     size_t length = 1;
 543     result = zstr_finalize (&s, &length);
 544     TEST_VERIFY_EXIT (result != NULL);
 545     TEST_VERIFY (*result == '\0');
 546     TEST_VERIFY (length == 1);
 547     TEST_VERIFY (zstr_size (&s) == 0);
 548     free (result);
 549   }
 550
 551   /* A few characters.  */
 552   {
 553     struct zstr s;
 554     zstr_init (&s);
 555     zstr_add (&s, 'A');
 556     zstr_add (&s, 'b');
 557     zstr_add (&s, 'c');
 558     zstr_add (&s, '\0');
 559     char *result = zstr_finalize (&s, NULL);
 560     TEST_VERIFY_EXIT (result != NULL);
 561     TEST_VERIFY (strcmp (result, "Abc") == 0);
 562     TEST_VERIFY (zstr_size (&s) == 0);
 563     free (result);
 564
 565     zstr_add (&s, 'X');
 566     zstr_add (&s, 'y');
 567     zstr_add (&s, 'z');
 568     zstr_add (&s, '\0');
 569     size_t length = 1;
 570     result = zstr_finalize (&s, &length);
 571     TEST_VERIFY_EXIT (result != NULL);
 572     TEST_VERIFY (strcmp (result, "Xyz") == 0);
 573     TEST_VERIFY (length == 4);
 574     TEST_VERIFY (zstr_size (&s) == 0);
 575     free (result);
 576   }
 577 }
 578
 579 static int
 580 do_test (void)
 581 {
 582   mtrace ();
 583   test_int ();
 584   test_str ();
 585   test_long_init ();
 586   test_long_overflow ();
 587   test_zstr ();
 588   return 0;
 589 }
 590
 591 #include <support/test-driver.c>