explicit ucontext_context_impl(Functor & cb, std::ptrdiff_t stack_size)
: m_stack_size(stack_size == -1 ? (std::ptrdiff_t)default_stack_size
: stack_size),
m_stack(alloc_stack(m_stack_size)),
cb_(&cb)
{
HPX_ASSERT(m_stack);
funp_ = &trampoline<Functor>;
int error = HPX_COROUTINE_MAKE_CONTEXT(
&m_ctx, m_stack, m_stack_size, funp_, cb_, nullptr);
HPX_UNUSED(error);
HPX_ASSERT(error == 0);
#if defined(HPX_HAVE_THREAD_STACKOVERFLOW_DETECTION)
// concept inspired by the following links:
//
// https://rethinkdb.com/blog/handling-stack-overflow-on-custom-stacks/
// http://www.evanjones.ca/software/threading.html
//
segv_stack.ss_sp = valloc(SEGV_STACK_SIZE);
segv_stack.ss_flags = 0;
segv_stack.ss_size = SEGV_STACK_SIZE;
std::memset(&action, '\0', sizeof(action));
action.sa_flags = SA_SIGINFO|SA_ONSTACK; //SA_STACK
action.sa_sigaction = &ucontext_context_impl::sigsegv_handler;
sigaltstack(&segv_stack, nullptr);
sigfillset(&action.sa_mask);
sigaction(SIGSEGV, &action, nullptr);
#endif
}
void rebind_stack()
{
if (m_stack) {
// just reset the context stack pointer to its initial value at the stack start
increment_stack_recycle_count();
int error = HPX_COROUTINE_MAKE_CONTEXT(
&m_ctx, m_stack, m_stack_size, (void (*)(void*))(funp_), &cb_, NULL);
HPX_UNUSED(error);
HPX_ASSERT(error == 0);
}
}
explicit ucontext_context_impl(Functor& cb, std::ptrdiff_t stack_size)
: m_stack_size(stack_size == -1? default_stack_size: stack_size),
m_stack(alloc_stack(m_stack_size))
{
HPX_ASSERT(m_stack);
typedef void cb_type(Functor*);
cb_type * cb_ptr = &trampoline<Functor>;
int error = HPX_COROUTINE_MAKE_CONTEXT(
&m_ctx, m_stack, m_stack_size, (void (*)(void*))(cb_ptr), &cb, NULL);
HPX_UNUSED(error);
HPX_ASSERT(error == 0);
}
explicit ucontext_context_impl(Functor& cb, std::ptrdiff_t stack_size)
: m_stack_size(stack_size == -1 ? (std::ptrdiff_t)default_stack_size : stack_size),
m_stack(alloc_stack(m_stack_size)),
cb_(cb)
{
HPX_ASSERT(m_stack);
funp_ = &trampoline<Functor>;
int error = HPX_COROUTINE_MAKE_CONTEXT(
&m_ctx, m_stack, m_stack_size, (void (*)(void*))(funp_), &cb_, NULL);
HPX_UNUSED(error);
HPX_ASSERT(error == 0);
}
