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diff --git a/mtasker_fcontext.cc b/mtasker_fcontext.cc
index bc37e76..8d96fa1 100644
--- a/mtasker_fcontext.cc
+++ b/mtasker_fcontext.cc
@@ -23,14 +23,15 @@
#include <exception>
#include <cassert>
#include <type_traits>
-#if BOOST_VERSION > 106100
-#include <boost/context/detail/fcontext.hpp>
-#else
-#include <boost/context/fcontext.hpp>
-#endif
#include <boost/version.hpp>
-
+#if BOOST_VERSION < 106100
+#include <boost/context/fcontext.hpp>
using boost::context::make_fcontext;
+#else
+#include <boost/context/detail/fcontext.hpp>
+using boost::context::detail::make_fcontext;
+#endif /* BOOST_VERSION < 106100 */
+
#if BOOST_VERSION < 105600
/* Note: This typedef means functions taking fcontext_t*, like jump_fcontext(),
@@ -61,8 +62,15 @@ jump_fcontext (fcontext_t* const ofc, fcontext_t const nfc,
}
}
#else
+
+#if BOOST_VERSION < 106100
using boost::context::fcontext_t;
using boost::context::jump_fcontext;
+#else
+using boost::context::detail::fcontext_t;
+using boost::context::detail::jump_fcontext;
+using boost::context::detail::transfer_t;
+#endif /* BOOST_VERSION < 106100 */
static_assert (std::is_pointer<fcontext_t>::value,
"Boost Context has changed the fcontext_t type again :-(");
@@ -72,7 +80,9 @@ static_assert (std::is_pointer<fcontext_t>::value,
* jump. args_t simply provides a way to pass more by reference.
*/
struct args_t {
+#if BOOST_VERSION < 106100
fcontext_t prev_ctx = nullptr;
+#endif
pdns_ucontext_t* self = nullptr;
boost::function<void(void)>* work = nullptr;
};
@@ -80,7 +90,11 @@ struct args_t {
extern "C" {
static
void
+#if BOOST_VERSION < 106100
threadWrapper (intptr_t const xargs) {
+#else
+threadWrapper (transfer_t const t) {
+#endif
/* Access the args passed from pdns_makecontext, and copy them directly from
* the calling stack on to ours (we're now using the MThreads stack).
* This saves heap allocating an args object, at the cost of an extra
@@ -90,11 +104,28 @@ threadWrapper (intptr_t const xargs) {
* the behaviour of the System V implementation, which can inherently only
* be passed ints and pointers.
*/
+#if BOOST_VERSION < 106100
auto args = reinterpret_cast<args_t*>(xargs);
+#else
+ auto args = reinterpret_cast<args_t*>(t.data);
+#endif
auto ctx = args->self;
auto work = args->work;
+ /* we switch back to pdns_makecontext() */
+#if BOOST_VERSION < 106100
jump_fcontext (reinterpret_cast<fcontext_t*>(&ctx->uc_mcontext),
static_cast<fcontext_t>(args->prev_ctx), 0);
+#else
+ transfer_t res = jump_fcontext (t.fctx, 0);
+ /* we got switched back from pdns_swapcontext() */
+ if (res.data) {
+ /* if res.data is not a nullptr, it holds a pointer to the context
+ we just switched from, and we need to fill it to be able to
+ switch back to it later. */
+ fcontext_t* ptr = static_cast<fcontext_t*>(res.data);
+ *ptr = res.fctx;
+ }
+#endif
args = nullptr;
try {
@@ -106,9 +137,14 @@ threadWrapper (intptr_t const xargs) {
/* Emulate the System V uc_link feature. */
auto const next_ctx = ctx->uc_link->uc_mcontext;
+#if BOOST_VERSION < 106100
jump_fcontext (reinterpret_cast<fcontext_t*>(&ctx->uc_mcontext),
static_cast<fcontext_t>(next_ctx),
static_cast<bool>(ctx->exception));
+#else
+ jump_fcontext (static_cast<fcontext_t>(next_ctx), 0);
+#endif
+
#ifdef NDEBUG
__builtin_unreachable();
#endif
@@ -129,10 +165,27 @@ pdns_ucontext_t::~pdns_ucontext_t
void
pdns_swapcontext
(pdns_ucontext_t& __restrict octx, pdns_ucontext_t const& __restrict ctx) {
+ /* we either switch back to threadwrapper() if it's the first time,
+ or we switch back to pdns_swapcontext(),
+ in both case we will be returning from a call to jump_fcontext(). */
+#if BOOST_VERSION < 106100
if (jump_fcontext (reinterpret_cast<fcontext_t*>(&octx.uc_mcontext),
static_cast<fcontext_t>(ctx.uc_mcontext), 0)) {
std::rethrow_exception (ctx.exception);
}
+#else
+ transfer_t res = jump_fcontext (static_cast<fcontext_t>(ctx.uc_mcontext), &octx.uc_mcontext);
+ if (res.data) {
+ /* if res.data is not a nullptr, it holds a pointer to the context
+ we just switched from, and we need to fill it to be able to
+ switch back to it later. */
+ fcontext_t* ptr = static_cast<fcontext_t*>(res.data);
+ *ptr = res.fctx;
+ }
+ if (ctx.exception) {
+ std::rethrow_exception (ctx.exception);
+ }
+#endif
}
void
@@ -146,7 +199,15 @@ pdns_makecontext
args_t args;
args.self = &ctx;
args.work = &start;
+ /* jumping to threadwrapper */
+#if BOOST_VERSION < 106100
jump_fcontext (reinterpret_cast<fcontext_t*>(&args.prev_ctx),
static_cast<fcontext_t>(ctx.uc_mcontext),
reinterpret_cast<intptr_t>(&args));
+#else
+ transfer_t res = jump_fcontext (static_cast<fcontext_t>(ctx.uc_mcontext),
+ &args);
+ /* back from threadwrapper, updating the context */
+ ctx.uc_mcontext = res.fctx;
+#endif
}
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