On Fri, 2016-07-15 at 18:21 -0700, Naveen Singh wrote:
I had this talk with Marcel few weeks back about compiling connman
Android/Brillo. This would surely give connman the penetration into
Android world and future IoT devices which are based of Brillo.
I actually got it compiled and working. There are two challenges:
a) Some of the libraries that are required by connman are missing.
my work I got those libraries compiled first.
b) Changes in connman itself: Open source connman does not compile as
such for Android/Brillo. There are some changes needed in connman to
get this going. I would like to see if we can upstream these changes.
The intent of this email is to discuss those changes. Following are
the changes needed:
1) Backtrace system call: In log.c from function print_backtrace we
call backtrace. It is a glibc API and is no present in bionic. There
is an equivalent function in bionic for doing this.
Backtrace printing was moved to its own file, src/backtrace.c, in
ConnMan 1.32, so this is just an automake check away.
2) hard check for ns_initparse in libresolv.so: There is no
libresolv.so for android/Brillo. All these ns_* symbols are part of
libc.so. So hard check has to go. We may need to check in
whether we are compiling against glibc or bionic early on and do
Yes, some automake magic needed.
3) NTP code calls adjtime to adjust clock. This function is missing
bionic. We may need to find a similar function in bionic for doing
The adjtimex patch on the ml will probably solve this. I'll take a look
at that patch nextish.
4) struct in6_pktinfo is defined in connman code (file
under #ifndef __USE_GNU. Now this structure is defined in bionic
header file libc/kernel/uapi/ipv6.h. Not sure what is the intent of
#ifndef __USE_GNU? Should this go away? Similarly struct in6_ifreq is
defined in inet.c file and it is also defined in the same bionic
header file. I had to comment out this definition to compile connman.
See commit message for e8784053a0a680ec8943ff20559c6561cb5b9a96.
For struct in6_ifreq it looks like very old code that should be fixed.
5) Some of the structures which are needed for connman compilation
defined under #ifdef __USE_BSD in bionic header file. For Bionic
__USE_BSD is defined only if _GNU_SOURCE is defined. So for those
files in connman we have to define _GNU_SOURCE as the first line in
that file. Example is ipv4ll.c. I hope this should be OK.
I'd like to keep the files as clean as possible. Looking at autoconf
magic, it seems to be possible to use AC_DEFINE to add values to the
generated config.h file, which is included first. config.h is used
everywhere and should be the first file included. So could one add the
needed defines in order to config.h with AC_DEFINE instead? And/or the
use of bionic, if needed?
6) GResolv structure in gresolv.c: struct __res_state is a member
GResolv structure. This structure is defined in resolv.h file in
glibc. struct __res_state in bionic requires inclusion of two other
header files resolv_private.h and res_private. Also this structure is
defined very differently between bionic and glibc. This caused
in gresolv.c, the way it accesses various members of this structure.
Ok, sounds a bit more complicated. You should perhaps post an RFC patch
for this so we have an idea of how complicated it becomes.
7) Struct sockaddr_in6 defined differently b/w bionic and glibc.
What is the difference here? Something that does not compile on both
8) ETH_ALEN is not defined in bionic header file
Should be easy once we know bionic is being used.
9) Need to include resolv_params.h in resolver.c. This is because
"MAXDNSRCH" etc is defined in resolv_params.h in bionic.
Automake/conf magic, I hope.
10) Needed to remove "-lresolv -lrt" from Makefile.am.
As above, I hope.
Some of these changes are easily doable if we can have #ifdef
in code. Through configure.ac we can detect if we are compiling
against bionic or glibc and appropriately turn on this flag. Not sure
what your thought are on this.
I'd go for configure.ac, it makes the code cleaner and uses
autoconf/automake for it's intended purpose. Let's start with the easy
Thanks for the heads up!