go/src/pkg/runtime/cgocall.c

// Copyright 2009 The Go Authors.  All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#include "runtime.h"
#include "cgocall.h"

Cgo *cgo;	/* filled in by dynamic linker when Cgo is available */
int64 ncgocall;

void
cgocall(void (*fn)(void*), void *arg)
{
	CgoWork w;
	CgoServer *s;

	ncgocall++;

	if(cgo == nil)
		throw("cgocall unavailable");

	noteclear(&w.note);
	w.next = nil;
	w.fn = fn;
	w.arg = arg;
	lock(&cgo->lock);
	if((s = cgo->idle) != nil) {
		cgo->idle = s->next;
		s->work = &w;
		unlock(&cgo->lock);
		notewakeup(&s->note);
	} else {
		if(cgo->whead == nil) {
			cgo->whead = &w;
		} else
			cgo->wtail->next = &w;
		cgo->wtail = &w;
		unlock(&cgo->lock);
	}
	notesleep(&w.note);
}

void
runtime·Cgocalls(int64 ret)
{
	ret = ncgocall;
	FLUSH(&ret);
}

void (*_cgo_malloc)(void*);
void (*_cgo_free)(void*);

void*
cmalloc(uintptr n)
{
	struct a {
		uint64 n;
		void *ret;
	} a;

	a.n = n;
	a.ret = nil;
	cgocall(_cgo_malloc, &a);
	return a.ret;
}

void
cfree(void *p)
{
	cgocall(_cgo_free, p);
}