localedata/tst-localedef-hardlinks.c

   1 /* Test --no-hard-links option to localedef.
   2    Copyright (C) 2020-2022 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 /* The test is designed to run in a container and execute localedef
  20    once without --no-hard-links, verify that there are 2 hard links to
  21    LC_CTYPE, and then run again *with* --no-hard-links and verify there
  22    are no hard links and link counts remain at 1.  The expectation here
  23    is that LC_CTYPE is identical for both locales because they are same
  24    empty locale but with a different name.  We use tests-container in
  25    this test because the hard link optimziation is only carried out for
  26    the default locale installation directory, and to write to that we
  27    need write access to that directory, enabled by 'su' via
  28    tests-container framework.  */
  29
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include <sys/stat.h>
  33 #include <sys/types.h>
  34 #include <sys/wait.h>
  35
  36 #include <support/check.h>
  37 #include <support/support.h>
  38 #include <support/xunistd.h>
  39 #include <support/capture_subprocess.h>
  40
  41 /* Each test compiles a locale to output, and has an expected link count
  42    for LC_CTYPE.  This test expects that localedef removes the existing
  43    files before installing new copies of the files, and we do not
  44    cleanup between localedef runs.  We can't cleanup between each pair
  45    of runs since localedef must see the existing locale in order to
  46    determine that space could be saved by using a hardlink.  */
  47 struct test_data
  48 {
  49   /* Arguments to localedef for this step.  */
  50   const char * argv[16];
  51   /* Expected output file generated by running localedef.  */
  52   const char *output;
  53   /* Expected st_nlink count for the output.  */
  54   int st_nlink;
  55 };
  56
  57 /* Check for link count.  */
  58 void
  59 check_link (struct test_data step)
  60 {
  61   struct stat64 locale;
  62   char *output;
  63
  64   output = xasprintf ("%s/%s", support_complocaledir_prefix, step.output);
  65   xstat (output, &locale);
  66   free (output);
  67   TEST_COMPARE (locale.st_nlink, step.st_nlink);
  68 }
  69
  70 static void
  71 run_localedef (void *step)
  72 {
  73   const char *prog = xasprintf ("%s/localedef", support_bindir_prefix);
  74   struct test_data *one = (struct test_data *) step;
  75
  76   one->argv[0] = prog;
  77   execv (prog, (char * const *) one->argv);
  78   FAIL_EXIT1 ("execv: %m");
  79 }
  80
  81 #define TEST1DIR "test1_locale.dir"
  82 #define TEST2DIR "test2_locale.dir"
  83
  84 /* The whole test has 4 steps described below.  Note the argv[0] NULL
  85    will be filled in at runtime by run_localedef.  */
  86 static struct test_data step[4] = {
  87   { .argv = { NULL, "--no-archive", "-i", "/test1_locale", TEST1DIR, NULL },
  88     .output = TEST1DIR "/LC_CTYPE",
  89     .st_nlink = 1 },
  90   { .argv = { NULL, "--no-archive", "-i", "/test2_locale", TEST2DIR, NULL },
  91     .output = TEST2DIR "/LC_CTYPE",
  92     .st_nlink = 2 },
  93   { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test1_locale",
  94               TEST1DIR, NULL },
  95     .output = TEST1DIR "/LC_CTYPE",
  96     .st_nlink = 1 },
  97   { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test2_locale",
  98               TEST1DIR, NULL },
  99     .output = TEST2DIR "/LC_CTYPE",
 100     .st_nlink = 1 },
 101 };
 102
 103 static int
 104 do_test (void)
 105 {
 106   struct support_capture_subprocess result;
 107
 108   printf ("INFO: $complocaledir is %s\n", support_complocaledir_prefix);
 109   /* Compile the first locale.  */
 110   result = support_capture_subprocess (run_localedef, (void *) &step[0]);
 111   support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
 112   check_link (step[0]);
 113
 114   /* This time around we should have link counts of 2 for the second
 115      linked locale since categories are identical.  */
 116   result = support_capture_subprocess (run_localedef, (void *) &step[1]);
 117   support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
 118   check_link (step[1]);
 119
 120   /* Again with --no-hard-links (link count is always one).  */
 121   result = support_capture_subprocess (run_localedef, (void *) &step[2]);
 122   support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
 123   check_link (step[2]);
 124
 125   /* Again with --no-hard-links, and the link count must remain 1.  */
 126   result = support_capture_subprocess (run_localedef, (void *) &step[3]);
 127   support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
 128   check_link (step[3]);
 129
 130   /* Tested without and with --no-hard-links and link counts were
 131      consistent.  */
 132   return EXIT_SUCCESS;
 133 }
 134
 135 #include <support/test-driver.c>