20 #ifndef __JackPortType__    21 #define __JackPortType__    24 #include "JackConstants.h"    30 extern jack_port_type_id_t PORT_TYPES_MAX;
    36     void (*init)(
void* buffer, 
size_t buffer_size, jack_nframes_t nframes);
    37     void (*mixdown)(
void *mixbuffer, 
void** src_buffers, 
int src_count, jack_nframes_t nframes);
    40 extern jack_port_type_id_t GetPortTypeId(
const char* port_type);
    41 extern const struct JackPortType* GetPortType(jack_port_type_id_t port_type_id);