stabilize build system: depends, installer, boost/bdb fixes, cross targets groundwork

depends/x86_64-pc-linux-gnu/include/boost/fiber/detail/futex.hpp

@@ -0,0 +1,61 @@
+
+//          Copyright Oliver Kowalke 2016.
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef BOOST_FIBERS_DETAIL_FUTEX_H
+#define BOOST_FIBERS_DETAIL_FUTEX_H
+
+#include <boost/config.hpp>
+#include <boost/predef.h> 
+
+#include <boost/fiber/detail/config.hpp>
+
+#if BOOST_OS_LINUX
+extern "C" {
+#include <linux/futex.h>
+#include <sys/syscall.h>
+}
+#elif BOOST_OS_WINDOWS
+#include <Windows.h>
+#endif
+
+namespace boost {
+namespace fibers {
+namespace detail {
+
+#if BOOST_OS_LINUX
+inline
+int sys_futex( void * addr, std::int32_t op, std::int32_t x) {
+    return ::syscall( SYS_futex, addr, op, x, nullptr, nullptr, 0);
+}
+
+inline
+int futex_wake( std::atomic< std::int32_t > * addr) {
+    return 0 <= sys_futex( static_cast< void * >( addr), FUTEX_WAKE_PRIVATE, 1) ? 0 : -1;
+}
+
+inline
+int futex_wait( std::atomic< std::int32_t > * addr, std::int32_t x) {
+    return 0 <= sys_futex( static_cast< void * >( addr), FUTEX_WAIT_PRIVATE, x) ? 0 : -1;
+}
+#elif BOOST_OS_WINDOWS
+inline
+int futex_wake( std::atomic< std::int32_t > * addr) {
+    ::WakeByAddressSingle( static_cast< void * >( addr) );
+    return 0;
+}
+
+inline
+int futex_wait( std::atomic< std::int32_t > * addr, std::int32_t x) {
+    ::WaitOnAddress( static_cast< volatile void * >( addr), & x, sizeof( x), INFINITE);
+    return 0;
+}
+#else
+# warn "no futex support on this platform"
+#endif
+
+}}}
+
+#endif // BOOST_FIBERS_DETAIL_FUTEX_H