support/tst-support_blob_repeat.c

   1 /* Tests for <support/blob_repeat.h>
   2    Copyright (C) 2018-2024 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 <stdio.h>
  20 #include <string.h>
  21 #include <support/blob_repeat.h>
  22 #include <support/check.h>
  23
  24 static int
  25 do_test (void)
  26 {
  27   struct support_blob_repeat repeat
  28     = support_blob_repeat_allocate ("5", 1, 5);
  29   TEST_COMPARE_BLOB (repeat.start, repeat.size, "55555", 5);
  30   support_blob_repeat_free (&repeat);
  31
  32   repeat = support_blob_repeat_allocate ("ABC", 3, 3);
  33   TEST_COMPARE_BLOB (repeat.start, repeat.size, "ABCABCABC", 9);
  34   support_blob_repeat_free (&repeat);
  35
  36   repeat = support_blob_repeat_allocate ("abc", 4, 3);
  37   TEST_COMPARE_BLOB (repeat.start, repeat.size, "abc\0abc\0abc", 12);
  38   support_blob_repeat_free (&repeat);
  39
  40   size_t gigabyte = 1U << 30;
  41   repeat = support_blob_repeat_allocate ("X", 1, gigabyte + 1);
  42   if (repeat.start == NULL)
  43     puts ("warning: not enough memory for 1 GiB mapping");
  44   else
  45     {
  46       TEST_COMPARE (repeat.size, gigabyte + 1);
  47       {
  48         unsigned char *p = repeat.start;
  49         for (size_t i = 0; i < gigabyte + 1; ++i)
  50           if (p[i] != 'X')
  51             FAIL_EXIT1 ("invalid byte 0x%02x at %zu", p[i], i);
  52
  53         /* Check that there is no sharing across the mapping.  */
  54         p[0] = 'Y';
  55         p[1U << 24] = 'Z';
  56         for (size_t i = 0; i < gigabyte + 1; ++i)
  57           if (i == 0)
  58             TEST_COMPARE (p[i], 'Y');
  59           else if (i == 1U << 24)
  60             TEST_COMPARE (p[i], 'Z');
  61           else if (p[i] != 'X')
  62             FAIL_EXIT1 ("invalid byte 0x%02x at %zu", p[i], i);
  63       }
  64     }
  65   support_blob_repeat_free (&repeat);
  66
  67   for (int do_shared = 0; do_shared < 2; ++do_shared)
  68     {
  69       if (do_shared)
  70         repeat = support_blob_repeat_allocate_shared ("012345678", 9,
  71                                                       10 * 1000 * 1000);
  72       else
  73         repeat = support_blob_repeat_allocate ("012345678", 9,
  74                                                10 * 1000 * 1000);
  75       if (repeat.start == NULL)
  76         puts ("warning: not enough memory for large mapping");
  77       else
  78         {
  79           unsigned char *p = repeat.start;
  80           for (int i = 0; i < 10 * 1000 * 1000; ++i)
  81             for (int j = 0; j <= 8; ++j)
  82               if (p[i * 9 + j] != '0' + j)
  83                 {
  84                   printf ("error: element %d index %d\n", i, j);
  85                   TEST_COMPARE (p[i * 9 + j], '0' + j);
  86                 }
  87
  88           enum { total_size = 9 * 10 * 1000 * 1000 };
  89           p[total_size - 1] = '\0';
  90           asm ("" ::: "memory");
  91           if (do_shared)
  92             /* The write is repeated in multiple places earlier in the
  93                string due to page sharing.  */
  94             TEST_VERIFY (strlen (repeat.start) < total_size - 1);
  95           else
  96             TEST_COMPARE (strlen (repeat.start), total_size - 1);
  97         }
  98       support_blob_repeat_free (&repeat);
  99     }
 100
 101   return 0;
 102 }
 103
 104 #include <support/test-driver.c>