bsnes-libretro/ucontext.c
Tim Allen ddffcd7600 Update to v094r28 release.
byuu says:

This WIP substantially restructures the ruby API for the first time
since that project started.

It is my hope that with this restructuring, destruction of the ruby
objects should now be deterministic, which should fix the crashing on
closing the emulator on Linux. We'll see I guess ... either way, it
removed two layers of wrappers from ruby, so it's a pretty nice code
cleanup.

It won't compile on Windows due to a few issues I didn't see until
uploading the WIP, too lazy to upload another. But I fixed all the
compilation issues locally, so it'll work on Windows again with the next
WIP (unless I break something else.)

(Kind of annoying that Linux defines glActiveTexture but Windows
doesn't.)
2015-06-20 15:44:05 +10:00

70 lines
1.7 KiB
C

/*
libco.ucontext (2008-01-28)
author: Nach
license: public domain
*/
/*
* WARNING: the overhead of POSIX ucontext is very high,
* assembly versions of libco or libco_sjlj should be much faster
*
* This library only exists for two reasons:
* 1 - as an initial test for the viability of a ucontext implementation
* 2 - to demonstrate the power and speed of libco over existing implementations,
* such as pth (which defaults to wrapping ucontext on unix targets)
*
* Use this library only as a *last resort*
*/
#define LIBCO_C
#include "libco.h"
#define _BSD_SOURCE
#include <stdlib.h>
#include <ucontext.h>
#ifdef __cplusplus
extern "C" {
#endif
static thread_local ucontext_t co_primary;
static thread_local ucontext_t *co_running = 0;
cothread_t co_active() {
if(!co_running) co_running = &co_primary;
return (cothread_t)co_running;
}
cothread_t co_create(unsigned int heapsize, void (*coentry)(void)) {
if(!co_running) co_running = &co_primary;
ucontext_t *thread = (ucontext_t*)malloc(sizeof(ucontext_t));
if(thread) {
if((!getcontext(thread) && !(thread->uc_stack.ss_sp = 0)) && (thread->uc_stack.ss_sp = malloc(heapsize))) {
thread->uc_link = co_running;
thread->uc_stack.ss_size = heapsize;
makecontext(thread, coentry, 0);
} else {
co_delete((cothread_t)thread);
thread = 0;
}
}
return (cothread_t)thread;
}
void co_delete(cothread_t cothread) {
if(cothread) {
if(((ucontext_t*)cothread)->uc_stack.ss_sp) { free(((ucontext_t*)cothread)->uc_stack.ss_sp); }
free(cothread);
}
}
void co_switch(cothread_t cothread) {
ucontext_t *old_thread = co_running;
co_running = (ucontext_t*)cothread;
swapcontext(old_thread, co_running);
}
#ifdef __cplusplus
}
#endif