[Buildroot] [PATCH 1/9] skalibs: new package

[Eric Le Bihan]

Hi!

Le Tue, 9 Aug 2016 10:06:22 +0200,
Thomas Petazzoni <thomas.petazzoni at free-electrons.com> a écrit :

> On Mon,  8 Aug 2016 23:02:12 +0200, Eric Le Bihan wrote:
> 
> > diff --git a/package/skalibs/Config.in b/package/skalibs/Config.in
> > new file mode 100644
> > index 0000000..db35681
> > --- /dev/null
> > +++ b/package/skalibs/Config.in
> > @@ -0,0 +1,12 @@
> > +config BR2_PACKAGE_SKALIBS
> > +	bool "skalibs"
> > +	depends on BR2_TOOLCHAIN_USES_GLIBC ||
> > BR2_TOOLCHAIN_USES_MUSL  
> 
> Can  you add a quick comment that explains why uClibc cannot build
> this package?
> 
> > +comment "skalibs need an (e)glibc or musl toolchain"  
> 
> Use just "glibc" instead of "(e)glibc", we have removed eglibc
> support.

As explained in my reply to Waldemar B. [1], I've found a fix, so this
limitation will be removed.

> > + trytypesize() {
> > +   echo "Checking size of $3..."
> > +-  $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO $LDFLAGS_AUTO -o
> > trysizeof$1 src/sysdeps/trysizeof$1.c +-
> > type_size=$(./trysizeof$1) || fail "$0: unable to determine size of
> > $3" ++  r=false ++  type_size=0
> > ++  while true; do
> > ++    cat<<EOF>trysizeof$1.c
> > ++#include <sys/types.h>
> > ++
> > ++int main(void)
> > ++{
> > ++  static int v = 1 / !!((sizeof($3) == $type_size));
> > ++  return 0;
> > ++}
> > ++EOF
> > ++    if $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO $LDFLAGS_AUTO -o
> > trysizeof$1 trysizeof$1.c 2>/dev/null; then ++        r=true
> > ++        break
> > ++    fi
> > ++    type_size=$(expr $type_size + 1)
> > ++    test $type_size -le 16 || break
> > ++  done
> > ++  test $r = true || fail "$0: unable to determine size of $3"
> > +   type_bits=$(expr 8 \* $type_size)
> > +-  rm -f trysizeof$1
> > ++  rm -f trysizeof$1 trysizeof$1.c
> > +   echo "sizeof$1: $type_size" >> $sysdeps/sysdeps
> > +   echo "#define ${package_macro_name}_SIZEOF$2 $type_size" >>
> > $sysdeps/sysdeps.h
> > +   echo "#define ${package_macro_name}_$2_BITS $type_bits" >>
> > $sysdeps/sysdeps.h  
> 
> Instead of doing this loop to find the size of the different types,
> what about using the following compiler pre-built defines (like you're
> doing for little endian vs. big endian detection below) :
> 
> $ sparc-linux-gcc -dM -E - </dev/null | grep SIZEOF
> #define __SIZEOF_INT__ 4
> #define __SIZEOF_POINTER__ 4
> #define __SIZEOF_LONG__ 4
> #define __SIZEOF_LONG_DOUBLE__ 16
> #define __SIZEOF_SIZE_T__ 4
> #define __SIZEOF_WINT_T__ 4
> #define __SIZEOF_PTRDIFF_T__ 4
> #define __SIZEOF_FLOAT__ 4
> #define __SIZEOF_SHORT__ 2
> #define __SIZEOF_WCHAR_T__ 4
> #define __SIZEOF_DOUBLE__ 8
> #define __SIZEOF_LONG_LONG__ 8

I did not know about this. Thanks for the suggestion. I'll rework the
patch.

> > ++#if defined(__BYTE_ORDER) && (__BYTE_ORDER == __BIG_ENDIAN)
> > ||	       \ ++	defined(__BYTE_ORDER__) &&
> > (__BYTE_ORDER__  == __ORDER_BIG_ENDIAN__) || \ ++
> > defined(__BIG_ENDIAN) ||				       \
> > ++	defined(__ARMEB__)
> > ||					       \ ++
> > defined(__THUMBEB__) ||				       \
> > ++	defined(__AARCH64EB__)
> > ||				       \ ++
> > defined(_MIPSEB) || defined(__MIPSEB) || defined(__MIPSEB__)  
> 
> Is there a reason why __BYTE_ORDER == __BIG_ENDIAN is not sufficient?
> It's not available for all compilers/compiler versions?

This check was written using information from [2], which lists all the
pre-defined endian macros. Maybe now GCC and Clang have a broader
support for __BIG_ENDIAN. I'll check.

> > +SKALIBS_VERSION = v2.3.10.0
> > +SKALIBS_SITE = git://git.skarnet.org/skalibs.git  
> 
> Please use the tarball at
> http://skarnet.org/software/skalibs/skalibs-2.3.10.0.tar.gz instead
> and add a hash file.

Will do!
 
> > +ifeq ($(BR2_STATIC_LIBS),y)
> > +SKALIBS_CONFIGURE_OPTS +=  --enable-static --disable-shared
> > +else
> > +SKALIBS_CONFIGURE_OPTS +=  --disable-static --enable-shared
> > --disable-allstatic +endif  
> 
> You forget the BR2_SHARED_STATIC_LIBS case, where we want both the
> shared and static libraries.

OK. I'll handle this new case.

> > +HOST_SKALIBS_CONFIGURE_OPTS = \
> > +	--prefix=/usr \
> > +	--disable-static \
> > +	--enable-shared \
> > +	--disable-allstatic  
> 
> You're adding of host variants of the packages, but I haven't yet
> understood why.

s6-rc is the service management program. The definitions of the services
and their dependencies are written in plain text files, then compiled
as a binary database. As it is not sensible to compile this on the
device, I provide a host variant of the compiler (s6-rc-compile) to
build the binary database during TARGET_FINALIZE_HOOKS. The host
variant of s6-rc requires the host variant of skalibs, execline and s6.

[1] http://lists.busybox.net/pipermail/buildroot/2016-August/169523.html
[2] https://sourceforge.net/p/predef/wiki/Endianness/

Thanks for the review!

Best regards,

-- 
ELB