void coopth_detach(void)
{
struct coopth_thrdata_t *thdata;
assert(_coopth_is_in_thread());
thdata = co_get_data(co_current());
ensure_single(thdata);
if (!thdata->attached)
return;
switch_state(COOPTH_DETACH);
}
/* for some time coopth_leave() was implemented on top of coopth_detach().
* This appeared not the best implementation. In particular, the commit
* 551371689 was needed to make leaving operation atomic, but this is
* not needed for detached threads at all. While the detached threads
* has a separate entry point (via coopth_run()), the left thread must
* not have a separate entry point. So it appeared better to return the
* special type "left" threads.
* Additionally the leave operation now calls the post handler immediately. */
void coopth_leave(void)
{
struct coopth_thrdata_t *thdata;
if (!_coopth_is_in_thread_nowarn())
return;
thdata = co_get_data(co_current());
ensure_single(thdata);
if (thdata->left)
return;
switch_state(COOPTH_LEAVE);
}
/* for some time coopth_leave() was implemented on top of coopth_detach().
* This appeared not the best implementation. In particular, the commit
* 551371689 was needed to make leaving operation atomic, but this is
* not needed for detached threads at all. While the detached threads
* has a separate entry point (via coopth_run()), the left thread must
* not have a separate entry point. So it appeared better to return the
* special type "left" threads.
* Additionally the leave operation now calls the post handler immediately,
* and it should be called from the context of the main thread. This is
* the reason why coopth_leave() for detached thread cannot be a no-op. */
void coopth_leave(void)
{
struct coopth_thrdata_t *thdata;
if (!_coopth_is_in_thread_nowarn())
return;
thdata = co_get_data(co_current());
ensure_single(thdata);
if (thdata->left)
return;
/* leaving detached thread should be atomic even wrt other detached
* threads. This is needed so that DPMI cannot run concurrently with
* leavedos().
* for joinable threads leaving should be atomic only wrt DOS code,
* but, because of an optimization loop in run_vm86(), it is actually
* also atomic wrt detached threads. */
if (!thdata->attached)
thdata->atomic_switch = 1;
switch_state(COOPTH_LEAVE);
}