string/tst-strerror-fail.c

   1 /* Check that strerror, strerror_l do not return NULL on  failure (bug 30555).
   2    Copyright (C) 2023-2024 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
  20 #include <locale.h>
  21 #include <stdbool.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <support/check.h>
  25 #include <support/namespace.h>
  26 #include <support/xdlfcn.h>
  27
  28 /* Interposed malloc that can be used to inject allocation failures.  */
  29
  30 static volatile bool fail_malloc;
  31
  32 void *
  33 malloc (size_t size)
  34 {
  35   if (fail_malloc)
  36     return NULL;
  37
  38   static void *(*original_malloc) (size_t);
  39   if (original_malloc == NULL)
  40     original_malloc = xdlsym (RTLD_NEXT, "malloc");
  41   return original_malloc (size);
  42 }
  43
  44 /* Callbacks for the actual tests.  Use fork to run both tests with a
  45    clean state.  */
  46
  47 static void
  48 test_strerror (void *closure)
  49 {
  50   fail_malloc = true;
  51   const char *s = strerror (999);
  52   fail_malloc = false;
  53   TEST_COMPARE_STRING (s, "Unknown error");
  54 }
  55
  56 static void
  57 test_strerror_l (void *closure)
  58 {
  59   locale_t loc = newlocale (LC_ALL, "C", (locale_t) 0);
  60   TEST_VERIFY (loc != (locale_t) 0);
  61   fail_malloc = true;
  62   const char *s = strerror_l (999, loc);
  63   fail_malloc = false;
  64   TEST_COMPARE_STRING (s, "Unknown error");
  65   freelocale (loc);
  66 }
  67
  68 static int
  69 do_test (void)
  70 {
  71   support_isolate_in_subprocess (test_strerror, NULL);
  72   support_isolate_in_subprocess (test_strerror_l, NULL);
  73
  74   return 0;
  75 }
  76
  77 #include <support/test-driver.c>