[PATCH] localedef: Add tests-container test for --no-hard-links.

[PATCH] localedef: Add tests-container test for --no-hard-links.

[Carlos O'Donell]

This test relies on the patch from here being applied:
https://sourceware.org/pipermail/libc-alpha/2020-April/113168.html

The test does what it says on the tin, and is the first time we actually
test localedef's behaviour in this case in a container.

I am always excited by extending our testing in this way to test previously
untestable (hardlink code) which requires being installed in default paths :-)

OK for master?

8< --- 8< --- 8<
From 6d6e1e3346eca93731fc47df20ddcdf4b5f53b4e Mon Sep 17 00:00:00 2001
From: Carlos O'Donell <carlos@redhat.com>
Date: Tue, 25 Feb 2020 10:15:30 -0500
Subject: [PATCH] localedef: Add tests-container test for --no-hard-links.

The new tst-localedef-hardlinks verifies that when compiling
two locales (with default output directory) one with
--no-hard-links and one without the option, results in the
expected behaviour.  When --no-hard-links is used the link
counts on LC_CTYPE is 1, indicating that even thoug the two
locale are identical (though different named source files and
output direcotry) the localedef did not carry out the hard
link optimization.  Then when --no-hard-links is omitted the
localedef hard link optimization is correctly carried out and
for 2 compiled locales the link count for LC_CTYPE is 2.
---
 localedata/Makefile                           |   2 +
 localedata/tst-localedef-hardlinks.c          | 130 ++++++++++++++++++
 .../postclean.req                             |   0
 .../tst-localedef-hardlinks.root/test1_locale |   3 +
 .../tst-localedef-hardlinks.root/test2_locale |   3 +
 .../tst-localedef-hardlinks.script            |  10 ++
 6 files changed, 148 insertions(+)
 create mode 100644 localedata/tst-localedef-hardlinks.c
 create mode 100644 localedata/tst-localedef-hardlinks.root/postclean.req
 create mode 100644 localedata/tst-localedef-hardlinks.root/test1_locale
 create mode 100644 localedata/tst-localedef-hardlinks.root/test2_locale
 create mode 100644 localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script

diff --git a/localedata/Makefile b/localedata/Makefile
index e89bacc1aa..ccfcb0049f 100644
--- a/localedata/Makefile
+++ b/localedata/Makefile
@@ -167,6 +167,8 @@ tests-special += $(objpfx)mtrace-tst-leaks.out
 endif
 endif
 endif
+tests-container = \
+			tst-localedef-hardlinks
 
 # Files to install.
 ifeq ($(INSTALL_UNCOMPRESSED),yes)
diff --git a/localedata/tst-localedef-hardlinks.c b/localedata/tst-localedef-hardlinks.c
new file mode 100644
index 0000000000..672a03ad45
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.c
@@ -0,0 +1,130 @@
+/* Test --no-hard-links option to localedef.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* The test is designed to run in a container and execute localedef
+   once without --no-hard-links, verify that there are 2 hard links to
+   LC_CTYPE, and then run again *with* --no-hard-links and verify there
+   are no hard links and link counts remain at 1.  The expectation here
+   is that LC_CTYPE is identical for both locales because they are same
+   empty locale but with a different name.  We use tests-container in
+   this test because the hard link optimziation is only carried out for
+   the default locale installation directory, and to write to that we
+   need write access to that directory, enabled by 'su' via
+   tests-container framework.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <support/check.h>
+#include <support/support.h>
+#include <support/xunistd.h>
+#include <support/capture_subprocess.h>
+
+/* Each test compiles a locale to output, and has an expected link count for
+   LC_CTYPE.  */
+struct test_data
+{
+  /* Arguments to localedef for this step.  */
+  const char * argv[16];
+  /* Expected output file generated by running localedef.  */
+  const char *output;
+  /* Expected st_nlink count for the output.  */
+  int st_nlink;
+};
+
+/* Check for link count.  */
+void
+check_link (struct test_data step)
+{
+  struct stat64 locale;
+  char *output;
+
+  output = xasprintf ("%s/%s", support_complocaledir_prefix, step.output);
+  xstat (output, &locale);
+  free (output);
+  TEST_COMPARE (locale.st_nlink, step.st_nlink);
+}
+
+static void
+run_localedef (void *step)
+{
+  const char *prog = xasprintf ("%s/localedef", support_bindir_prefix);
+  struct test_data *one = (struct test_data *) step;
+
+  one->argv[0] = prog;
+  execv (prog, (char * const *) one->argv);
+  FAIL_EXIT1 ("execv: %m");
+}
+
+#define TEST1DIR "test1_locale.dir"
+#define TEST2DIR "test2_locale.dir"
+
+/* The whole test has 4 steps described below.  */
+static struct test_data step[4] = {
+  { .argv = { NULL, "--no-archive", "-i", "/test1_locale", TEST1DIR, NULL },
+    .output = TEST1DIR "/LC_CTYPE",
+    .st_nlink = 1 },
+  { .argv = { NULL, "--no-archive", "-i", "/test2_locale", TEST2DIR, NULL },
+    .output = TEST2DIR "/LC_CTYPE",
+    .st_nlink = 2 },
+  { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test1_locale",
+	      TEST1DIR, NULL },
+    .output = TEST1DIR "/LC_CTYPE",
+    .st_nlink = 1 },
+  { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test2_locale",
+	      TEST1DIR, NULL },
+    .output = TEST2DIR "/LC_CTYPE",
+    .st_nlink = 1 },
+};
+
+static int
+do_test (void)
+{
+  struct support_capture_subprocess result;
+
+  printf ("INFO: $complocaledir is %s\n", support_complocaledir_prefix);
+  /* Compile the first locale.  */
+  result = support_capture_subprocess (run_localedef, (void *) &step[0]);
+  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
+  check_link (step[0]);
+
+  /* This time around we should have link counts of 2 for the second
+     linked locale since categories are identical.  */
+  result = support_capture_subprocess (run_localedef, (void *) &step[1]);
+  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
+  check_link (step[1]);
+
+  /* Again with --no-hard-links (link count is always one).  */
+  result = support_capture_subprocess (run_localedef, (void *) &step[2]);
+  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
+  check_link (step[2]);
+
+  /* Again with --no-hard-links, and the link count must remain 1.  */
+  result = support_capture_subprocess (run_localedef, (void *) &step[3]);
+  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
+  check_link (step[3]);
+
+  /* Tested without and with --no-hard-links and link counts were
+     consistent.  */
+  return EXIT_SUCCESS;
+}
+
+#include <support/test-driver.c>
diff --git a/localedata/tst-localedef-hardlinks.root/postclean.req b/localedata/tst-localedef-hardlinks.root/postclean.req
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/localedata/tst-localedef-hardlinks.root/test1_locale b/localedata/tst-localedef-hardlinks.root/test1_locale
new file mode 100644
index 0000000000..79f4c3aec4
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.root/test1_locale
@@ -0,0 +1,3 @@
+comment_char %
+escape_char /
+% Empty test locale.  Must be identical to the other test locale.
diff --git a/localedata/tst-localedef-hardlinks.root/test2_locale b/localedata/tst-localedef-hardlinks.root/test2_locale
new file mode 100644
index 0000000000..79f4c3aec4
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.root/test2_locale
@@ -0,0 +1,3 @@
+comment_char %
+escape_char /
+% Empty test locale.  Must be identical to the other test locale.
diff --git a/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script b/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script
new file mode 100644
index 0000000000..7c737aceb0
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script
@@ -0,0 +1,10 @@
+# Need root to write to $complocaledir when running localedef.
+su
+
+# The container install ensures we have uncompressed charmaps so we don't
+# need gzip, and we don't need to copy in the uncompressed charmap from
+# the source tree.
+
+# We need to create all the parent directories to install the locales
+# into.
+mkdirp 0755 $complocaledir/
-- 
2.21.1


-- 
Cheers,
Carlos.

Re: [PATCH] localedef: Add tests-container test for --no-hard-links.

[DJ Delorie]

"Carlos O'Donell" <carlos@redhat.com> writes:
> OK for master?

Minor comments about comments but functionally OK.

Reviewed-by: DJ Delorie <dj@redhat.com>

> +tests-container = \
> +			tst-localedef-hardlinks

New test, ok.

> +/* Test --no-hard-links option to localedef.
> +   Copyright (C) 2018 Free Software Foundation, Inc.

2018 ?

> +   <http://www.gnu.org/licenses/>.  */

https

> +/* Each test compiles a locale to output, and has an expected link count for
> +   LC_CTYPE.  */

I don't see any cleanup between each step, do we rely on localedef to
remove and replace any output files each time?  And/or is that what
we're testing?  Either way, I suspect such expectations should be
documented in the comment so that future test readers can share these
expectations.

> +struct test_data
> +{
> +  /* Arguments to localedef for this step.  */
> +  const char * argv[16];

Overkill ;-)

> +  /* Expected output file generated by running localedef.  */
> +  const char *output;

Ok.

> +  /* Expected st_nlink count for the output.  */
> +  int st_nlink;

Ok.

> +/* Check for link count.  */
> +void
> +check_link (struct test_data step)
> +{
> +  struct stat64 locale;
> +  char *output;
> +
> +  output = xasprintf ("%s/%s", support_complocaledir_prefix, step.output);
> +  xstat (output, &locale);
> +  free (output);
> +  TEST_COMPARE (locale.st_nlink, step.st_nlink);
> +}

Ok.

> +static void
> +run_localedef (void *step)
> +{
> +  const char *prog = xasprintf ("%s/localedef", support_bindir_prefix);
> +  struct test_data *one = (struct test_data *) step;
> +
> +  one->argv[0] = prog;
> +  execv (prog, (char * const *) one->argv);
> +  FAIL_EXIT1 ("execv: %m");
> +}

Ok.  

> +#define TEST1DIR "test1_locale.dir"
> +#define TEST2DIR "test2_locale.dir"
> +
> +/* The whole test has 4 steps described below.  */
> +static struct test_data step[4] = {
> +  { .argv = { NULL, "--no-archive", "-i", "/test1_locale", TEST1DIR, NULL },
> +    .output = TEST1DIR "/LC_CTYPE",
> +    .st_nlink = 1 },
> +  { .argv = { NULL, "--no-archive", "-i", "/test2_locale", TEST2DIR, NULL },
> +    .output = TEST2DIR "/LC_CTYPE",
> +    .st_nlink = 2 },
> +  { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test1_locale",
> +	      TEST1DIR, NULL },
> +    .output = TEST1DIR "/LC_CTYPE",
> +    .st_nlink = 1 },
> +  { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test2_locale",
> +	      TEST1DIR, NULL },
> +    .output = TEST2DIR "/LC_CTYPE",
> +    .st_nlink = 1 },
> +};

Ok.  Might want to add that the "NULL" will be filled in at runtime.

> +static int
> +do_test (void)
> +{
> +  struct support_capture_subprocess result;
> +
> +  printf ("INFO: $complocaledir is %s\n", support_complocaledir_prefix);
> +  /* Compile the first locale.  */
> +  result = support_capture_subprocess (run_localedef, (void *) &step[0]);
> +  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
> +  check_link (step[0]);
> +
> +  /* This time around we should have link counts of 2 for the second
> +     linked locale since categories are identical.  */
> +  result = support_capture_subprocess (run_localedef, (void *) &step[1]);
> +  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
> +  check_link (step[1]);
> +
> +  /* Again with --no-hard-links (link count is always one).  */
> +  result = support_capture_subprocess (run_localedef, (void *) &step[2]);
> +  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
> +  check_link (step[2]);
> +
> +  /* Again with --no-hard-links, and the link count must remain 1.  */
> +  result = support_capture_subprocess (run_localedef, (void *) &step[3]);
> +  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
> +  check_link (step[3]);
> +
> +  /* Tested without and with --no-hard-links and link counts were
> +     consistent.  */
> +  return EXIT_SUCCESS;
> +}

Ok.

> +#include <support/test-driver.c>

Ok.

> diff --git a/localedata/tst-localedef-hardlinks.root/postclean.req b/localedata/tst-localedef-hardlinks.root/postclean.req
> new file mode 100644
> index 0000000000..e69de29bb2

I wonder if we should include a comment in this file (contents are
otherwise ignored) saying why it's justified.  In this case, I assume
that having test locales hang around might influence future tests if
they're loaded and matched by default?

> diff --git a/localedata/tst-localedef-hardlinks.root/test1_locale b/localedata/tst-localedef-hardlinks.root/test1_locale
> new file mode 100644
> index 0000000000..79f4c3aec4
> --- /dev/null
> +++ b/localedata/tst-localedef-hardlinks.root/test1_locale
> @@ -0,0 +1,3 @@
> +comment_char %
> +escape_char /
> +% Empty test locale.  Must be identical to the other test locale.

Ok.

> diff --git a/localedata/tst-localedef-hardlinks.root/test2_locale b/localedata/tst-localedef-hardlinks.root/test2_locale
> new file mode 100644
> index 0000000000..79f4c3aec4
> --- /dev/null
> +++ b/localedata/tst-localedef-hardlinks.root/test2_locale
> @@ -0,0 +1,3 @@
> +comment_char %
> +escape_char /
> +% Empty test locale.  Must be identical to the other test locale.

Ok.

> diff --git a/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script b/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script
> new file mode 100644
> index 0000000000..7c737aceb0
> --- /dev/null
> +++ b/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script
> @@ -0,0 +1,10 @@
> +# Need root to write to $complocaledir when running localedef.
> +su
> +
> +# The container install ensures we have uncompressed charmaps so we don't
> +# need gzip, and we don't need to copy in the uncompressed charmap from
> +# the source tree.
> +
> +# We need to create all the parent directories to install the locales
> +# into.
> +mkdirp 0755 $complocaledir/

Ok.

[PATCHv2] localedef: Add tests-container test for --no-hard-links.

[Carlos O'Donell]

On 4/28/20 2:28 PM, DJ Delorie wrote:
> 
> "Carlos O'Donell" <carlos@redhat.com> writes:
>> OK for master?
> 
> Minor comments about comments but functionally OK.
> 
> Reviewed-by: DJ Delorie <dj@redhat.com>
> 
>> +tests-container = \
>> +			tst-localedef-hardlinks
> 
> New test, ok.
> 
>> +/* Test --no-hard-links option to localedef.
>> +   Copyright (C) 2018 Free Software Foundation, Inc.
> 
> 2018 ?

Fixed.

> 
>> +   <http://www.gnu.org/licenses/>.  */
> 
> https

Fixed. 

> 
>> +/* Each test compiles a locale to output, and has an expected link count for
>> +   LC_CTYPE.  */
> 
> I don't see any cleanup between each step, do we rely on localedef to
> remove and replace any output files each time?  And/or is that what
> we're testing?  Either way, I suspect such expectations should be
> documented in the comment so that future test readers can share these
> expectations.

Fixed.

Yes, we expect localedef to remove the files and replace them.

~~~
-/* Each test compiles a locale to output, and has an expected link count for
-   LC_CTYPE.  */
+/* Each test compiles a locale to output, and has an expected link count
+   for LC_CTYPE.  This test expects that localedef removes the existing
+   files before installing new copies of the files, and we do not
+   cleanup between localedef runs.  We can't cleanup between each pair
+   of runs since localedef must see the existing locale in order to
+   determine that space could be saved by using a hardlink.  */
~~~

>> +struct test_data
>> +{
>> +  /* Arguments to localedef for this step.  */
>> +  const char * argv[16];
> 
> Overkill ;-)

Right, we're at 6 args, so I gave some room.

We really need some dynamic APIs for writing test closures.

I don't want ad-hoc methods for creating closures.

> 
>> +  /* Expected output file generated by running localedef.  */
>> +  const char *output;
> 
> Ok.
> 
>> +  /* Expected st_nlink count for the output.  */
>> +  int st_nlink;
> 
> Ok.
> 
>> +/* Check for link count.  */
>> +void
>> +check_link (struct test_data step)
>> +{
>> +  struct stat64 locale;
>> +  char *output;
>> +
>> +  output = xasprintf ("%s/%s", support_complocaledir_prefix, step.output);
>> +  xstat (output, &locale);
>> +  free (output);
>> +  TEST_COMPARE (locale.st_nlink, step.st_nlink);
>> +}
> 
> Ok.
> 
>> +static void
>> +run_localedef (void *step)
>> +{
>> +  const char *prog = xasprintf ("%s/localedef", support_bindir_prefix);
>> +  struct test_data *one = (struct test_data *) step;
>> +
>> +  one->argv[0] = prog;
>> +  execv (prog, (char * const *) one->argv);
>> +  FAIL_EXIT1 ("execv: %m");
>> +}
> 
> Ok.  
> 
>> +#define TEST1DIR "test1_locale.dir"
>> +#define TEST2DIR "test2_locale.dir"
>> +
>> +/* The whole test has 4 steps described below.  */
>> +static struct test_data step[4] = {
>> +  { .argv = { NULL, "--no-archive", "-i", "/test1_locale", TEST1DIR, NULL },
>> +    .output = TEST1DIR "/LC_CTYPE",
>> +    .st_nlink = 1 },
>> +  { .argv = { NULL, "--no-archive", "-i", "/test2_locale", TEST2DIR, NULL },
>> +    .output = TEST2DIR "/LC_CTYPE",
>> +    .st_nlink = 2 },
>> +  { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test1_locale",
>> +	      TEST1DIR, NULL },
>> +    .output = TEST1DIR "/LC_CTYPE",
>> +    .st_nlink = 1 },
>> +  { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test2_locale",
>> +	      TEST1DIR, NULL },
>> +    .output = TEST2DIR "/LC_CTYPE",
>> +    .st_nlink = 1 },
>> +};
> 
> Ok.  Might want to add that the "NULL" will be filled in at runtime.
> 

Fixed.

>> +static int
>> +do_test (void)
>> +{
>> +  struct support_capture_subprocess result;
>> +
>> +  printf ("INFO: $complocaledir is %s\n", support_complocaledir_prefix);
>> +  /* Compile the first locale.  */
>> +  result = support_capture_subprocess (run_localedef, (void *) &step[0]);
>> +  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
>> +  check_link (step[0]);
>> +
>> +  /* This time around we should have link counts of 2 for the second
>> +     linked locale since categories are identical.  */
>> +  result = support_capture_subprocess (run_localedef, (void *) &step[1]);
>> +  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
>> +  check_link (step[1]);
>> +
>> +  /* Again with --no-hard-links (link count is always one).  */
>> +  result = support_capture_subprocess (run_localedef, (void *) &step[2]);
>> +  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
>> +  check_link (step[2]);
>> +
>> +  /* Again with --no-hard-links, and the link count must remain 1.  */
>> +  result = support_capture_subprocess (run_localedef, (void *) &step[3]);
>> +  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
>> +  check_link (step[3]);
>> +
>> +  /* Tested without and with --no-hard-links and link counts were
>> +     consistent.  */
>> +  return EXIT_SUCCESS;
>> +}
> 
> Ok.
> 
>> +#include <support/test-driver.c>
> 
> Ok.
> 
>> diff --git a/localedata/tst-localedef-hardlinks.root/postclean.req b/localedata/tst-localedef-hardlinks.root/postclean.req
>> new file mode 100644
>> index 0000000000..e69de29bb2
> 
> I wonder if we should include a comment in this file (contents are
> otherwise ignored) saying why it's justified.  In this case, I assume
> that having test locales hang around might influence future tests if
> they're loaded and matched by default?

Correct.

Fixed.

>> diff --git a/localedata/tst-localedef-hardlinks.root/test1_locale b/localedata/tst-localedef-hardlinks.root/test1_locale
>> new file mode 100644
>> index 0000000000..79f4c3aec4
>> --- /dev/null
>> +++ b/localedata/tst-localedef-hardlinks.root/test1_locale
>> @@ -0,0 +1,3 @@
>> +comment_char %
>> +escape_char /
>> +% Empty test locale.  Must be identical to the other test locale.
> 
> Ok.
> 
>> diff --git a/localedata/tst-localedef-hardlinks.root/test2_locale b/localedata/tst-localedef-hardlinks.root/test2_locale
>> new file mode 100644
>> index 0000000000..79f4c3aec4
>> --- /dev/null
>> +++ b/localedata/tst-localedef-hardlinks.root/test2_locale
>> @@ -0,0 +1,3 @@
>> +comment_char %
>> +escape_char /
>> +% Empty test locale.  Must be identical to the other test locale.
> 
> Ok.
> 
>> diff --git a/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script b/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script
>> new file mode 100644
>> index 0000000000..7c737aceb0
>> --- /dev/null
>> +++ b/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script
>> @@ -0,0 +1,10 @@
>> +# Need root to write to $complocaledir when running localedef.
>> +su
>> +
>> +# The container install ensures we have uncompressed charmaps so we don't
>> +# need gzip, and we don't need to copy in the uncompressed charmap from
>> +# the source tree.
>> +
>> +# We need to create all the parent directories to install the locales
>> +# into.
>> +mkdirp 0755 $complocaledir/
> 
> Ok.
> 

v2
- Fix date.
- Fix https
- Add extra comment about file overwrite expecatations.
- Add comment about argv[0] getting filled in (it's dynamic and depends
  on bindir).
- Add comment to postclean.req.

OK for master?

8< --- 8< --- 8<
From 67854155584856bab4849b01ecf51aab67048bbb Mon Sep 17 00:00:00 2001
From: Carlos O'Donell <carlos@redhat.com>
Date: Tue, 25 Feb 2020 10:15:30 -0500
Subject: [PATCH] localedef: Add tests-container test for --no-hard-links.

The new tst-localedef-hardlinks verifies that when compiling
two locales (with default output directory) one with
--no-hard-links and one without the option, results in the
expected behaviour.  When --no-hard-links is used the link
counts on LC_CTYPE is 1, indicating that even thoug the two
locale are identical (though different named source files and
output direcotry) the localedef did not carry out the hard
link optimization.  Then when --no-hard-links is omitted the
localedef hard link optimization is correctly carried out and
for 2 compiled locales the link count for LC_CTYPE is 2.

Reviewed-by: DJ Delorie <dj@redhat.com>
---
 localedata/Makefile                           |   2 +
 localedata/tst-localedef-hardlinks.c          | 135 ++++++++++++++++++
 .../postclean.req                             |   2 +
 .../tst-localedef-hardlinks.root/test1_locale |   3 +
 .../tst-localedef-hardlinks.root/test2_locale |   3 +
 .../tst-localedef-hardlinks.script            |   9 ++
 6 files changed, 154 insertions(+)
 create mode 100644 localedata/tst-localedef-hardlinks.c
 create mode 100644 localedata/tst-localedef-hardlinks.root/postclean.req
 create mode 100644 localedata/tst-localedef-hardlinks.root/test1_locale
 create mode 100644 localedata/tst-localedef-hardlinks.root/test2_locale
 create mode 100644 localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script

diff --git a/localedata/Makefile b/localedata/Makefile
index e89bacc1aa..ccfcb0049f 100644
--- a/localedata/Makefile
+++ b/localedata/Makefile
@@ -167,6 +167,8 @@ tests-special += $(objpfx)mtrace-tst-leaks.out
 endif
 endif
 endif
+tests-container = \
+			tst-localedef-hardlinks
 
 # Files to install.
 ifeq ($(INSTALL_UNCOMPRESSED),yes)
diff --git a/localedata/tst-localedef-hardlinks.c b/localedata/tst-localedef-hardlinks.c
new file mode 100644
index 0000000000..e8fda167be
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.c
@@ -0,0 +1,135 @@
+/* Test --no-hard-links option to localedef.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* The test is designed to run in a container and execute localedef
+   once without --no-hard-links, verify that there are 2 hard links to
+   LC_CTYPE, and then run again *with* --no-hard-links and verify there
+   are no hard links and link counts remain at 1.  The expectation here
+   is that LC_CTYPE is identical for both locales because they are same
+   empty locale but with a different name.  We use tests-container in
+   this test because the hard link optimziation is only carried out for
+   the default locale installation directory, and to write to that we
+   need write access to that directory, enabled by 'su' via
+   tests-container framework.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <support/check.h>
+#include <support/support.h>
+#include <support/xunistd.h>
+#include <support/capture_subprocess.h>
+
+/* Each test compiles a locale to output, and has an expected link count
+   for LC_CTYPE.  This test expects that localedef removes the existing
+   files before installing new copies of the files, and we do not
+   cleanup between localedef runs.  We can't cleanup between each pair
+   of runs since localedef must see the existing locale in order to
+   determine that space could be saved by using a hardlink.  */
+struct test_data
+{
+  /* Arguments to localedef for this step.  */
+  const char * argv[16];
+  /* Expected output file generated by running localedef.  */
+  const char *output;
+  /* Expected st_nlink count for the output.  */
+  int st_nlink;
+};
+
+/* Check for link count.  */
+void
+check_link (struct test_data step)
+{
+  struct stat64 locale;
+  char *output;
+
+  output = xasprintf ("%s/%s", support_complocaledir_prefix, step.output);
+  xstat (output, &locale);
+  free (output);
+  TEST_COMPARE (locale.st_nlink, step.st_nlink);
+}
+
+static void
+run_localedef (void *step)
+{
+  const char *prog = xasprintf ("%s/localedef", support_bindir_prefix);
+  struct test_data *one = (struct test_data *) step;
+
+  one->argv[0] = prog;
+  execv (prog, (char * const *) one->argv);
+  FAIL_EXIT1 ("execv: %m");
+}
+
+#define TEST1DIR "test1_locale.dir"
+#define TEST2DIR "test2_locale.dir"
+
+/* The whole test has 4 steps described below.  Note the argv[0] NULL
+   will be filled in at runtime by run_localedef.  */
+static struct test_data step[4] = {
+  { .argv = { NULL, "--no-archive", "-i", "/test1_locale", TEST1DIR, NULL },
+    .output = TEST1DIR "/LC_CTYPE",
+    .st_nlink = 1 },
+  { .argv = { NULL, "--no-archive", "-i", "/test2_locale", TEST2DIR, NULL },
+    .output = TEST2DIR "/LC_CTYPE",
+    .st_nlink = 2 },
+  { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test1_locale",
+	      TEST1DIR, NULL },
+    .output = TEST1DIR "/LC_CTYPE",
+    .st_nlink = 1 },
+  { .argv = { NULL, "--no-archive", "--no-hard-links", "-i", "/test2_locale",
+	      TEST1DIR, NULL },
+    .output = TEST2DIR "/LC_CTYPE",
+    .st_nlink = 1 },
+};
+
+static int
+do_test (void)
+{
+  struct support_capture_subprocess result;
+
+  printf ("INFO: $complocaledir is %s\n", support_complocaledir_prefix);
+  /* Compile the first locale.  */
+  result = support_capture_subprocess (run_localedef, (void *) &step[0]);
+  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
+  check_link (step[0]);
+
+  /* This time around we should have link counts of 2 for the second
+     linked locale since categories are identical.  */
+  result = support_capture_subprocess (run_localedef, (void *) &step[1]);
+  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
+  check_link (step[1]);
+
+  /* Again with --no-hard-links (link count is always one).  */
+  result = support_capture_subprocess (run_localedef, (void *) &step[2]);
+  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
+  check_link (step[2]);
+
+  /* Again with --no-hard-links, and the link count must remain 1.  */
+  result = support_capture_subprocess (run_localedef, (void *) &step[3]);
+  support_capture_subprocess_check (&result, "execv", 1, sc_allow_stderr);
+  check_link (step[3]);
+
+  /* Tested without and with --no-hard-links and link counts were
+     consistent.  */
+  return EXIT_SUCCESS;
+}
+
+#include <support/test-driver.c>
diff --git a/localedata/tst-localedef-hardlinks.root/postclean.req b/localedata/tst-localedef-hardlinks.root/postclean.req
new file mode 100644
index 0000000000..48f3c4bd4e
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.root/postclean.req
@@ -0,0 +1,2 @@
+# We do not want test locales to remain installed for future tests so
+# we request that the testroot be cleaned after the test is complete.
diff --git a/localedata/tst-localedef-hardlinks.root/test1_locale b/localedata/tst-localedef-hardlinks.root/test1_locale
new file mode 100644
index 0000000000..79f4c3aec4
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.root/test1_locale
@@ -0,0 +1,3 @@
+comment_char %
+escape_char /
+% Empty test locale.  Must be identical to the other test locale.
diff --git a/localedata/tst-localedef-hardlinks.root/test2_locale b/localedata/tst-localedef-hardlinks.root/test2_locale
new file mode 100644
index 0000000000..79f4c3aec4
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.root/test2_locale
@@ -0,0 +1,3 @@
+comment_char %
+escape_char /
+% Empty test locale.  Must be identical to the other test locale.
diff --git a/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script b/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script
new file mode 100644
index 0000000000..dd88663530
--- /dev/null
+++ b/localedata/tst-localedef-hardlinks.root/tst-localedef-hardlinks.script
@@ -0,0 +1,9 @@
+# Need root to write to $complocaledir when running localedef.
+su
+
+# The container install ensures we have uncompressed charmaps so we don't
+# need gzip, and we don't need to copy in the uncompressed charmap from
+# the source tree.
+
+# The container install ensures we have the compiled locale dirctory
+# present for localedef to write to by default.
-- 
2.21.1


-- 
Cheers,
Carlos.

Re: [PATCHv2] localedef: Add tests-container test for --no-hard-links.

[DJ Delorie]

"Carlos O'Donell" <carlos@redhat.com> writes:

> v2
> - Fix date.
> - Fix https
> - Add extra comment about file overwrite expecatations.
> - Add comment about argv[0] getting filled in (it's dynamic and depends
>   on bindir).
> - Add comment to postclean.req.
>
> OK for master?

Ok.  Be careful to not push this one before the one that adds the
Makefile mkdirp patch ;-)

Reviewed-by: DJ Delorie <dj@redhat.com>

Re: [PATCHv2] localedef: Add tests-container test for --no-hard-links.

[Carlos O'Donell]

On 4/29/20 5:44 PM, DJ Delorie wrote:
> "Carlos O'Donell" <carlos@redhat.com> writes:
> 
>> v2
>> - Fix date.
>> - Fix https
>> - Add extra comment about file overwrite expecatations.
>> - Add comment about argv[0] getting filled in (it's dynamic and depends
>>   on bindir).
>> - Add comment to postclean.req.
>>
>> OK for master?
> 
> Ok.  Be careful to not push this one before the one that adds the
> Makefile mkdirp patch ;-)
> 
> Reviewed-by: DJ Delorie <dj@redhat.com>
> 

Thanks!

Pushed as #2 in sequence.

-- 
Cheers,
Carlos.