svn commit: r295561 - in head: include sys/mips/include sys/powerpc/include sys/sparc64/include sys/sys sys/x86/include

[Bruce Evans]

On Sat, 13 Feb 2016, Konstantin Belousov wrote:

> On Sat, Feb 13, 2016 at 07:29:48AM +1100, Bruce Evans wrote:
>> It needs a version number to be correct.  Plain __POSIX_VISIBLE means
>> all versions.  __POSIX_VISBLE >= 200112 is probably good enough for
>> the POSIX part.  I don't know the correct number for XSI.  Perhaps
>> it can be simply omitted.  _XOPEN_SOURCE >= 600 gives
>> __XSI_VISIBLE >= 600 && _POSIX_C_SOURCE >= 200112.  So __XSI_VISIBLE
>> in the above is only to support XSI before 2001.  We only support 1
>> XSI before that -- #500 which corresponds to 1996 POSIX.  Very likely
>> XSI did have ucontext_t then, so the above ifdef is correct.  It is
>> just hard to read.  Easier than google hits though :-).  I found a
>> gnu man page about getcontext() being in SVID but couldn't easily
>> find the history.
>
> I have SVID document labeled FINAL COPY June 15, 1995 First Edition.
> There, it seems that ucontext.h is required.
>
> Below is the updated patch.
>
> diff --git a/include/signal.h b/include/signal.h
> index 33be55c..217fadd 100644
> --- a/include/signal.h
> +++ b/include/signal.h
> @@ -36,8 +36,10 @@
> #include <sys/cdefs.h>
> #include <sys/_types.h>
> #include <sys/signal.h>
> +#if __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE
> #include <machine/ucontext.h>
> #include <sys/_ucontext.h>
> +#endif
>
> #if __BSD_VISIBLE
> /*

Good.

The old visibility bugs with mc_* should be fixed someday.  I said that
uc_* could be used.  _mc_* should have been used originally.  Maybe we
can just change to either of these, since nothing except libc should
have used the internals of mcontext_t.

Bruce