Raspberry PI / Android a minimal cross-compile configuration

Enable a cross compile Erlang/OTP platform to Android or Raspberry PI
using Android NDK. Port emulator and core application to support target
HW platform. Exclude any add-on services required for OTP platform deployment
into target hardware due to device fragmentation and jail-break requirements.

 * fix erts/emulator/beam/sys.h
   Disable redefinition of __noreturn macro

 * port erts/emulator/sys/unix/erl_child_setup.c
   Use techniques proposed by https://code.google.com/p/erlang4android to
   access system properties

 * fix erts/emulator/sys/unix/erl_unix_sys_ddll.c
   The static linking of emulator cannot find dlerror(), dlopen() symbols

 * port erts/emulator/sys/unix/sys.c
   make path to shell configurable at build time

 * port erts/etc/common/Makefile.in
   disable librt for *-linux-androideabi

 * port erts/lib_src/pthread/ethread.c
   Use techniques proposed by https://code.google.com/p/erlang4android to
   disable emulator crash if kernel threads are on. Replace unreliable
   pthread_sigmask() by sigprocmask()

 * port lib/erl_interface/src/connect/ei_connect.c
   Disable call to undefined gethostid()

 * port lib/erl_interface/src/connect/ei_resolve.c
   Use gethostbyname_r() on Android platform

1 files changed, 5 insertions, 1 deletions

diff --git a/erts/lib_src/pthread/ethread.c b/erts/lib_src/pthread/ethread.c
index 7f27b5f29c..79784c5b84 100644
--- a/erts/lib_src/pthread/ethread.c
+++ b/erts/lib_src/pthread/ethread.c
@@ -541,7 +541,11 @@ int ethr_sigmask(int how, const sigset_t *set, sigset_t *oset)
 	return EINVAL;
     }
 #endif
-  return pthread_sigmask(how, set, oset);
+#if defined(__ANDROID__)
+   return sigprocmask(how, set, oset);
+#else 
+   return pthread_sigmask(how, set, oset);
+#endif    
 }
 
 int ethr_sigwait(const sigset_t *set, int *sig)