jack/port.h

   1 /*
   2     Copyright (C) 2001 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU Lesser General Public License as published by
   6     the Free Software Foundation; either version 2.1 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU Lesser General Public License for more details.
  13
  14     You should have received a copy of the GNU Lesser General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17
  18     $Id$
  19 */
  20
  21 #ifndef __jack_port_h__
  22 #define __jack_port_h__
  23
  24 #include <pthread.h>
  25 #include <jack/types.h>
  26 #include <jack/jslist.h>
  27 #include <jack/shm.h>
  28
  29 #define JACK_PORT_NAME_SIZE 256
  30 #define JACK_PORT_TYPE_SIZE 32
  31
  32 /* The relatively low value of this constant reflects the fact that
  33  * JACK currently only knows about *2* port types.  (May 2006)
  34  *
  35  * Further, the 4 covers:
  36  *   - a single non-negotiated audio format
  37  *   - music data (ie. MIDI)
  38  *   - video
  39  *   - one other
  40  *
  41  * which is probably enough for more than just the foreseeable future.
  42  */
  43 #define JACK_MAX_PORT_TYPES 4
  44 #define JACK_AUDIO_PORT_TYPE 0
  45 #define JACK_MIDI_PORT_TYPE 1
  46
  47 /* these should probably go somewhere else, but not in <jack/types.h> */
  48 #define JACK_CLIENT_NAME_SIZE 33
  49 typedef uint32_t jack_client_id_t;
  50
  51 /* JACK shared memory segments are limited to MAX_INT32, they can be
  52  * shared between 32-bit and 64-bit clients.
  53  */
  54 #define JACK_SHM_MAX (MAX_INT32)
  55 typedef int32_t jack_port_type_id_t;
  56
  57 /* Port type structure.
  58  *
  59  *  (1) One for each port type is part of the engine's jack_control_t
  60  *  shared memory structure.
  61  *
  62  *  (2) One for each port type is appended to the engine's
  63  *  jack_client_connect_result_t response.  The client reads them into
  64  *  its local memory, using them to attach the corresponding shared
  65  *  memory segments.
  66  */
  67 typedef struct _jack_port_type_info {
  68
  69     jack_port_type_id_t ptype_id;
  70     const char     type_name[JACK_PORT_TYPE_SIZE];
  71
  72     /* If == 1, then a buffer to handle nframes worth of data has
  73      * sizeof(jack_default_audio_sample_t) * nframes bytes.
  74      *
  75      * If > 1, the buffer allocated for input mixing will be
  76      * this value times sizeof(jack_default_audio_sample_t)
  77      * * nframes bytes in size.  For non-audio data types,
  78      * it may have a different value.
  79      *
  80      * If < 0, the value should be ignored, and buffer_size
  81      * should be used.
  82      */
  83     int32_t buffer_scale_factor;
  84
  85     /* ignored unless buffer_scale_factor is < 0. see above */
  86     jack_shmsize_t buffer_size;
  87
  88     jack_shm_registry_index_t shm_registry_index;
  89
  90     jack_shmsize_t zero_buffer_offset;
  91
  92 } jack_port_type_info_t;
  93
  94 /* Allocated by the engine in shared memory. */
  95 typedef struct _jack_port_shared {
  96
  97     jack_port_type_id_t      ptype_id;  /* index into port type array */
  98     jack_shmsize_t           offset;    /* buffer offset in shm segment */
  99     jack_port_id_t           id;        /* index into engine port array */
 100     enum JackPortFlags       flags;
 101     char                     name[JACK_CLIENT_NAME_SIZE+JACK_PORT_NAME_SIZE];
 102     jack_client_id_t         client_id; /* who owns me */
 103
 104     volatile jack_nframes_t  latency;
 105     volatile jack_nframes_t  total_latency;
 106     volatile uint8_t         monitor_requests;
 107
 108     char                     has_mixdown; /* port has a mixdown function */
 109     char                     in_use;
 110     char                     unused; /* legacy locked field */
 111
 112 } jack_port_shared_t;
 113
 114 typedef struct _jack_port_functions {
 115
 116     /* Function to initialize port buffer. Cannot be NULL.
 117      * NOTE: This must take a buffer rather than jack_port_t as it is called
 118      * in jack_engine_place_buffers() before any port creation.
 119      * A better solution is to make jack_engine_place_buffers to be type-specific,
 120      * but this works.
 121      */
 122     void (*buffer_init)(void *buffer, size_t size);
 123
 124     /* Function to mixdown multiple inputs to a buffer.  Can be NULL,
 125      * indicating that multiple input connections are not legal for
 126      * this data type.
 127      */
 128     void (*mixdown)(jack_port_t *, jack_nframes_t);
 129
 130 } jack_port_functions_t;
 131
 132 /**
 133  * Get port functions.
 134  * @param ptid port type id.
 135  *
 136  * @return pointer to port type functions or NULL if port type is unknown.
 137  */
 138 /*const*/ jack_port_functions_t *
 139 jack_get_port_functions(jack_port_type_id_t ptid);
 140
 141
 142 /* Allocated by the client in local memory. */
 143 struct _jack_port {
 144     void                    **client_segment_base;
 145     void                     *mix_buffer;
 146     jack_port_type_info_t    *type_info; /* shared memory type info */
 147     struct _jack_port_shared *shared;    /* corresponding shm struct */
 148     struct _jack_port        *tied;      /* locally tied source port */
 149     jack_port_functions_t    fptr;
 150     pthread_mutex_t          connection_lock;
 151     JSList                   *connections;
 152 };
 153
 154 /*  Inline would be cleaner, but it needs to be fast even in
 155  *  non-optimized code.  jack_output_port_buffer() only handles output
 156  *  ports.  jack_port_buffer() works for both input and output ports.
 157  */
 158 #define jack_port_buffer(p) \
 159   ((void *) ((p)->mix_buffer? (p)->mix_buffer: \
 160    *(p)->client_segment_base + (p)->shared->offset))
 161 #define jack_output_port_buffer(p) \
 162   ((void *) (*(p)->client_segment_base + (p)->shared->offset))
 163
 164 #endif /* __jack_port_h__ */
 165