nss_wrapper support for musl-libc

[Andreas Schneider]

On Wednesday, 25 January 2017 23:47:23 CET Dennis Schridde wrote:
> Hello!

Hi Dennis,


thank you very much for your contribution!
 
> I made a few changes to nss_wrapper to get it to run on musl-libc 1.1
> (Alpine Linux 3.5). Please find the patch attached.
> 
> One test failed, without me being able to fix it: gethostent returns NULL on
> musl-libc, but I don't know what might cause this or whether the test is
> actually valid for musl-libc. If you could provide me with further
> information on the purpose and expected behaviour of this function (the
> information on the net was rather scarce) or why it might return NULL in
> this case, I would be very glad.

The only documentation is the source. You need to dig there to see what is 
going on.

> 
> If you want to test this, I suggest using my Dockerfile [1] as a basis. By
> also installing "cmocka" and changing the build instructions at the bottom
> appropriately, you can run the testsuite.
> 
> I would be glad if you could integrate this into your sources for the next
> release. If you have concerns about my changes, related to coding style or
> anything else, please do not hesitate to explain to me how I should improve
> this code to allow inclusion into your sources.

The changes to src/nss_wrapper.c are fine, if you comment #else and #endif, 
like:

#ifdef HAVE_GETPWENT_R
...
#else /* HAVE_GETPWENT_R */
...
#endif /* HAVE_GETPWENT_R */

This makes it easier to understand which #ifdef it is is.


About tests/test_getaddrinfo.c:

I think you should report those to the developers of musl-libc. These tests 
pass correctly on Linux, Solaris and BSD. All have different libc 
implementations.

 	rc = getaddrinfo(NULL, "echo", &hints, &res);
-	assert_int_equal(rc, EAI_NONAME);
+	if (rc != EAI_SERVICE) { // musl-libc returns EAI_SERVICE
+		assert_int_equal(rc, EAI_NONAME);
+	}

I would argue that EAI_NONAME is the correct error code here as it is NULL. 
EAI_SERICE is obviously the wrong return code.


The changes to tests/testsuite.c are fine if comments are added. Please make 
seperate commits for each file.


Thanks!


	Andreas



-- 
Andreas Schneider                   GPG-ID: CC014E3D
Samba Team                             asn at samba.org
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