malloc/tst-mallinfo2.c

   1 /* Smoke test for mallinfo2
   2    Copyright (C) 2020-2023 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 /* Test that mallinfo2 is properly exported and basically works.  */
  20
  21 #include <array_length.h>
  22 #include <malloc.h>
  23 #include <stdlib.h>
  24 #include <support/check.h>
  25
  26 /* This is not specifically needed for the test, but (1) does
  27    something to the data so gcc doesn't optimize it away, and (2) may
  28    help when developing future tests.  */
  29 static void
  30 print_mi (const char *msg, struct mallinfo2 *m)
  31 {
  32   printf("\n%s...\n", msg);
  33 #define P(f) printf("%s: %zu\n", #f, m->f)
  34   P(arena);
  35   P(ordblks);
  36   P(smblks);
  37   P(hblks);
  38   P(hblkhd);
  39   P(usmblks);
  40   P(fsmblks);
  41   P(uordblks);
  42   P(fordblks);
  43   P(keepcost);
  44 }
  45
  46 /* We do this to force the call to malloc to not be optimized
  47    away.  */
  48 volatile void *ptr;
  49
  50 static int
  51 do_test (void)
  52 {
  53   struct mallinfo2 mi1, mi2;
  54   int i;
  55   size_t total = 0;
  56
  57   /* This is the key difference between mallinfo() and mallinfo2().
  58      It may be a false positive if int and size_t are the same
  59      size.  */
  60   TEST_COMPARE (sizeof (mi1.arena), sizeof (size_t));
  61
  62   mi1 = mallinfo2 ();
  63   print_mi ("before", &mi1);
  64
  65   /* Allocations that are meaningful-sized but not so large as to be
  66      mmapped, so that they're all accounted for in the field we test
  67      below.  */
  68   for (i = 1; i < 20; ++i)
  69     {
  70       ptr = malloc (160 * i);
  71       total += 160 * i;
  72     }
  73
  74   mi2 = mallinfo2 ();
  75   print_mi ("after", &mi2);
  76
  77   /* Check at least something changed.  */
  78   TEST_VERIFY (mi2.uordblks >= mi1.uordblks + total);
  79
  80   return 0;
  81 }
  82
  83 #include <support/test-driver.c>