Implement f{,try,un}lockfile

Drop UART write if it would block

Author: Extrems

libogc/console.c

@@ -597,9 +597,10 @@ static ssize_t __console_write_r(struct _reent *r,void *fd,const char *ptr,size_
 {
 	ssize_t ret = __console_write(r,fd,ptr,len);
 
-	if(stdcon) {
-		if(ret!=-1) _fwrite_r(r,ptr,1,len,stdcon);
-		else ret = _fwrite_r(r,ptr,1,len,stdcon);
+	if(stdcon && !ftrylockfile(stdcon)) {
+		if(ret!=-1) _fwrite_unlocked_r(r,ptr,1,len,stdcon);
+		else ret = _fwrite_unlocked_r(r,ptr,1,len,stdcon);
+		funlockfile(stdcon);
 	}
 	return ret;
 }

libogc/lock_supp.c

@@ -77,3 +77,18 @@ void __syscall_lock_release(_LOCK_T *lock)
 	plock = (mutex_t)*lock;
 	LWP_MutexUnlock(plock);
 }
+
+void flockfile(FILE *fp)
+{
+	__lock_acquire_recursive(fp->_lock);
+}
+
+int ftrylockfile(FILE *fp)
+{
+	return ({ __lock_try_acquire_recursive(fp->_lock); });
+}
+
+void funlockfile(FILE *fp)
+{
+	__lock_release_recursive(fp->_lock);
+}