/*
* call-seq:
* fiber.transfer(args, ...) -> obj
*
* Transfers control to receiver fiber of the method call.
* Unlike <code>resume</code> the receiver wouldn't be pushed to call
* stack of fibers. Instead it will switch to the call stack of
* transferring fiber.
* When resuming a fiber that was transferred to another fiber it would
* cause double resume error. Though when the fiber is re-transferred
* and <code>Fiber.yield</code> is called, the fiber would be resumable.
*/
static mrb_value
fiber_transfer(mrb_state *mrb, mrb_value self)
{
struct mrb_context *c = fiber_check(mrb, self);
mrb_value* a;
mrb_int len;
fiber_check_cfunc(mrb, mrb->c);
mrb_get_args(mrb, "*", &a, &len);
if (c == mrb->root_c) {
mrb->c->status = MRB_FIBER_TRANSFERRED;
mrb->c = c;
c->status = MRB_FIBER_RUNNING;
MARK_CONTEXT_MODIFY(c);
mrb_write_barrier(mrb, (struct RBasic*)c->fib);
return fiber_result(mrb, a, len);
}
if (c == mrb->c) {
return fiber_result(mrb, a, len);
}
return fiber_switch(mrb, self, len, a, FALSE, FALSE);
}
/*
* call-seq:
* fiber.resume(args, ...) -> obj
*
* Resumes the fiber from the point at which the last <code>Fiber.yield</code>
* was called, or starts running it if it is the first call to
* <code>resume</code>. Arguments passed to resume will be the value of
* the <code>Fiber.yield</code> expression or will be passed as block
* parameters to the fiber's block if this is the first <code>resume</code>.
*
* Alternatively, when resume is called it evaluates to the arguments passed
* to the next <code>Fiber.yield</code> statement inside the fiber's block
* or to the block value if it runs to completion without any
* <code>Fiber.yield</code>
*/
static mrb_value
fiber_resume(mrb_state *mrb, mrb_value self)
{
struct mrb_context *c = fiber_check(mrb, self);
mrb_value *a;
int len;
mrb_callinfo *ci;
for (ci = c->ci; ci >= c->cibase; ci--) {
if (ci->acc < 0) {
mrb_raise(mrb, E_ARGUMENT_ERROR, "can't cross C function boundary");
}
}
if (c->status == MRB_FIBER_RESUMED) {
mrb_raise(mrb, E_RUNTIME_ERROR, "double resume");
}
if (c->status == MRB_FIBER_TERMINATED) {
mrb_raise(mrb, E_RUNTIME_ERROR, "resuming dead fiber");
}
mrb_get_args(mrb, "*", &a, &len);
mrb->c->status = MRB_FIBER_RESUMED;
if (c->status == MRB_FIBER_CREATED) {
mrb_value *b = c->stack+1;
mrb_value *e = b + len;
while (b<e) {
*b++ = *a++;
}
c->cibase->argc = len;
c->prev = mrb->c;
if (c->prev->fib)
mrb_field_write_barrier(mrb, (struct RBasic*)c->fib, (struct RBasic*)c->prev->fib);
mrb_write_barrier(mrb, (struct RBasic*)c->fib);
c->status = MRB_FIBER_RUNNING;
mrb->c = c;
MARK_CONTEXT_MODIFY(c);
return c->ci->proc->env->stack[0];
}
MARK_CONTEXT_MODIFY(c);
c->prev = mrb->c;
if (c->prev->fib)
mrb_field_write_barrier(mrb, (struct RBasic*)c->fib, (struct RBasic*)c->prev->fib);
mrb_write_barrier(mrb, (struct RBasic*)c->fib);
c->status = MRB_FIBER_RUNNING;
mrb->c = c;
return fiber_result(mrb, a, len);
}
static mrb_value
fiber_switch(mrb_state *mrb, mrb_value self, mrb_int len, const mrb_value *a, mrb_bool resume)
{
struct mrb_context *c = fiber_check(mrb, self);
mrb_callinfo *ci;
for (ci = c->ci; ci >= c->cibase; ci--) {
if (ci->acc < 0) {
mrb_raise(mrb, E_FIBER_ERROR, "can't cross C function boundary");
}
}
if (resume && c->status == MRB_FIBER_TRANSFERRED) {
mrb_raise(mrb, E_FIBER_ERROR, "resuming transfered fiber");
}
if (c->status == MRB_FIBER_RUNNING || c->status == MRB_FIBER_RESUMING) {
mrb_raise(mrb, E_FIBER_ERROR, "double resume");
}
if (c->status == MRB_FIBER_TERMINATED) {
mrb_raise(mrb, E_FIBER_ERROR, "resuming dead fiber");
}
mrb->c->status = resume ? MRB_FIBER_RESUMING : MRB_FIBER_TRANSFERRED;
c->prev = resume ? mrb->c : (c->prev ? c->prev : mrb->root_c);
if (c->status == MRB_FIBER_CREATED) {
mrb_value *b = c->stack+1;
mrb_value *e = b + len;
while (b<e) {
*b++ = *a++;
}
c->cibase->argc = len;
if (c->prev->fib)
mrb_field_write_barrier(mrb, (struct RBasic*)c->fib, (struct RBasic*)c->prev->fib);
mrb_write_barrier(mrb, (struct RBasic*)c->fib);
c->status = MRB_FIBER_RUNNING;
mrb->c = c;
MARK_CONTEXT_MODIFY(c);
return c->ci->proc->env->stack[0];
}
MARK_CONTEXT_MODIFY(c);
if (c->prev->fib)
mrb_field_write_barrier(mrb, (struct RBasic*)c->fib, (struct RBasic*)c->prev->fib);
mrb_write_barrier(mrb, (struct RBasic*)c->fib);
c->status = MRB_FIBER_RUNNING;
mrb->c = c;
return fiber_result(mrb, a, len);
}
static mrb_value
fiber_switch(mrb_state *mrb, mrb_value self, mrb_int len, const mrb_value *a, mrb_bool resume, mrb_bool vmexec)
{
struct mrb_context *c = fiber_check(mrb, self);
struct mrb_context *old_c = mrb->c;
mrb_value value;
fiber_check_cfunc(mrb, c);
if (resume && c->status == MRB_FIBER_TRANSFERRED) {
mrb_raise(mrb, E_FIBER_ERROR, "resuming transferred fiber");
}
if (c->status == MRB_FIBER_RUNNING || c->status == MRB_FIBER_RESUMED) {
mrb_raise(mrb, E_FIBER_ERROR, "double resume (fib)");
}
if (c->status == MRB_FIBER_TERMINATED) {
mrb_raise(mrb, E_FIBER_ERROR, "resuming dead fiber");
}
mrb->c->status = resume ? MRB_FIBER_RESUMED : MRB_FIBER_TRANSFERRED;
c->prev = resume ? mrb->c : (c->prev ? c->prev : mrb->root_c);
if (c->status == MRB_FIBER_CREATED) {
mrb_value *b = c->stack+1;
mrb_value *e = b + len;
while (b<e) {
*b++ = *a++;
}
c->cibase->argc = len;
value = c->stack[0] = c->ci->proc->env->stack[0];
}
else {
value = fiber_result(mrb, a, len);
}
mrb_write_barrier(mrb, (struct RBasic*)c->fib);
c->status = MRB_FIBER_RUNNING;
mrb->c = c;
if (vmexec) {
c->vmexec = TRUE;
value = mrb_vm_exec(mrb, c->ci[-1].proc, c->ci->pc);
mrb->c = old_c;
}
else {
MARK_CONTEXT_MODIFY(c);
}
return value;
}
/* mrb_fiber_yield() must be called as `return mrb_fiber_yield(...)` */
MRB_API mrb_value
mrb_fiber_yield(mrb_state *mrb, mrb_int len, const mrb_value *a)
{
struct mrb_context *c = mrb->c;
if (!c->prev) {
mrb_raise(mrb, E_FIBER_ERROR, "can't yield from root fiber");
}
c->prev->status = MRB_FIBER_RUNNING;
c->status = MRB_FIBER_SUSPENDED;
mrb->c = c->prev;
c->prev = NULL;
if (c->vmexec) {
c->vmexec = FALSE;
mrb->c->ci->acc = CI_ACC_RESUMED;
}
mrb_write_barrier(mrb, (struct RBasic*)c->fib);
MARK_CONTEXT_MODIFY(mrb->c);
return fiber_result(mrb, a, len);
}
mrb_value
mrb_fiber_yield(mrb_state *mrb, int len, mrb_value *a)
{
struct mrb_context *c = mrb->c;
mrb_callinfo *ci;
for (ci = c->ci; ci >= c->cibase; ci--) {
if (ci->acc < 0) {
mrb_raise(mrb, E_ARGUMENT_ERROR, "can't cross C function boundary");
}
}
if (!c->prev) {
mrb_raise(mrb, E_ARGUMENT_ERROR, "can't yield from root fiber");
}
c->prev->status = MRB_FIBER_RUNNING;
mrb->c = c->prev;
c->prev = NULL;
MARK_CONTEXT_MODIFY(mrb->c);
return fiber_result(mrb, a, len);
}
/*
* call-seq:
* Fiber.yield(args, ...) -> obj
*
* Yields control back to the context that resumed the fiber, passing
* along any arguments that were passed to it. The fiber will resume
* processing at this point when <code>resume</code> is called next.
* Any arguments passed to the next <code>resume</code> will be the
* value that this <code>Fiber.yield</code> expression evaluates to.
*/
static mrb_value fiber_yield(mrb_state *mrb, mrb_value self)
{
struct mrb_context *c = mrb->m_ctx;
mrb_callinfo *ci;
mrb_value *a;
int len;
for (ci = c->m_ci; ci >= c->cibase; ci--) {
if (ci->acc < 0) {
mrb->mrb_raise(E_ARGUMENT_ERROR, "can't cross C function boundary");
}
}
if (!c->prev) {
mrb->mrb_raise(E_ARGUMENT_ERROR, "can't yield from root fiber");
}
mrb_get_args(mrb, "*", &a, &len);
c->prev->status = MRB_FIBER_RUNNING;
mrb->m_ctx = c->prev;
c->prev = NULL;
MARK_CONTEXT_MODIFY(mrb->m_ctx);
return fiber_result(mrb, a, len);
}
MRB_API mrb_value
mrb_fiber_yield(mrb_state *mrb, mrb_int len, const mrb_value *a)
{
struct mrb_context *c = mrb->c;
mrb_callinfo *ci;
for (ci = c->ci; ci >= c->cibase; ci--) {
if (ci->acc < 0) {
mrb_raise(mrb, E_FIBER_ERROR, "can't cross C function boundary");
}
}
if (!c->prev) {
mrb_raise(mrb, E_FIBER_ERROR, "can't yield from root fiber");
}
c->prev->status = MRB_FIBER_RUNNING;
c->status = MRB_FIBER_SUSPENDED;
mrb->c = c->prev;
c->prev = NULL;
MARK_CONTEXT_MODIFY(mrb->c);
mrb_write_barrier(mrb, (struct RBasic*)c->fib);
return fiber_result(mrb, a, len);
}