darwin 386 start

src/libthread/Darwin-386.c

@@ -0,0 +1,23 @@
+#include "threadimpl.h"
+
+void
+makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
+{
+	int *sp;
+
+	sp = (int*)ucp->uc_stack.ss_sp+ucp->uc_stack.ss_size/4;
+	sp -= argc;
+	memmove(sp, &argc+1, argc*sizeof(int));
+	*--sp = 0;		/* return address */
+	ucp->uc_mcontext.mc_eip = (long)func;
+	ucp->uc_mcontext.mc_esp = (int)sp;
+}
+
+int
+swapcontext(ucontext_t *oucp, ucontext_t *ucp)
+{
+	if(getcontext(oucp) == 0)
+		setcontext(ucp);
+	return 0;
+}
+