[1/1] trousers: fix build issue with musl

With musl C library, we get following build error when building trousers:

  tsp_tcsi_param.c:14:28: fatal error: bits/local_lim.h: No such file or directory
   #include <bits/local_lim.h>
                              ^
  compilation terminated.

Header <bits/local_lim.h> is not available in musl. tsp_tcsi_param.c
uses this for macro HOST_NAME_MAX.

This patch add support for checking presence of header <bits/local_lim.h>.
And based on that we include it or define macro HOST_NAME_MAX to 64 if
it is not already defined.

Value 64 is chosen because <bits/local_lim.h> also uses same value.

Fixes:

  http://autobuild.buildroot.net/results/c9b/c9b13ae8d4af9ae6a65921de142c0e8da30664e0/

Signed-off-by: Rahul Bedarkar <rahul.bedarkar@imgtec.com>
---
 .../trousers/0003-fix-build-issue-with-musl.patch  | 52 ++++++++++++++++++++++
 1 file changed, 52 insertions(+)
 create mode 100644 package/trousers/0003-fix-build-issue-with-musl.patch

Hello,

On Sat, 20 Aug 2016 17:26:04 +0530, Rahul Bedarkar wrote:
> With musl C library, we get following build error when building trousers:
> 
>   tsp_tcsi_param.c:14:28: fatal error: bits/local_lim.h: No such file or directory
>    #include <bits/local_lim.h>
>                               ^
>   compilation terminated.
> 
> Header <bits/local_lim.h> is not available in musl. tsp_tcsi_param.c
> uses this for macro HOST_NAME_MAX.
> 
> This patch add support for checking presence of header <bits/local_lim.h>.
> And based on that we include it or define macro HOST_NAME_MAX to 64 if
> it is not already defined.
> 
> Value 64 is chosen because <bits/local_lim.h> also uses same value.

This seems like the wrong approach to fix the problem. Indeed, musl
does have a definition of HOST_NAME_MAX, except it's in <limits.h>.

uClibc and glibc also have HOST_NAME_MAX defined when <limits.h> is
included, so the right fix is to drop completely the <bits/local_lim.h>
inclusion, and include <limits.h> instead.

I've tested the following program:

==
#include <limits.h>
#include <stdio.h>

int main(void)
{
	printf("%d\n", HOST_NAME_MAX);
	return 0;
}
==

and it builds fine with glibc, uClibc and musl.

Could you rework your patch accordingly, and also submit the patch
upstream to the trousers project?

Thanks!

Thomas

Hi Thomas,

On Saturday 20 August 2016 06:11 PM, Thomas Petazzoni wrote:
> Hello,
>
>
> This seems like the wrong approach to fix the problem. Indeed, musl
> does have a definition of HOST_NAME_MAX, except it's in <limits.h>.
>
> uClibc and glibc also have HOST_NAME_MAX defined when <limits.h> is
> included, so the right fix is to drop completely the <bits/local_lim.h>
> inclusion, and include <limits.h> instead.
>
> I've tested the following program:
>
> ==
> #include <limits.h>
> #include <stdio.h>
>
> int main(void)
> {
> 	printf("%d\n", HOST_NAME_MAX);
> 	return 0;
> }
> ==
>
> and it builds fine with glibc, uClibc and musl.
>
> Could you rework your patch accordingly, and also submit the patch
> upstream to the trousers project?
>

Thanks for comments. Even on Trousers project mailing list someone 
proposed similar patch. 
https://sourceforge.net/p/trousers/mailman/message/35261558/

Since we can't download it and it's based on upstream master branch, I 
will add separate patch here and I don't need to submit it upstream as 
it's likely to get merged.


Thanks,
Rahul

Hello,

On Mon, 22 Aug 2016 19:22:55 +0530, Rahul Bedarkar wrote:

> Thanks for comments. Even on Trousers project mailing list someone 
> proposed similar patch. 
> https://sourceforge.net/p/trousers/mailman/message/35261558/
> 
> Since we can't download it and it's based on upstream master branch, I 
> will add separate patch here and I don't need to submit it upstream as 
> it's likely to get merged.

Romain has been faster than you:

  https://patchwork.ozlabs.org/patch/661295/

Thomas