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Diffstat (limited to 'portmidi/pm_mac/pmmacosxcm.c')
| -rwxr-xr-x | portmidi/pm_mac/pmmacosxcm.c | 1179 |
1 files changed, 1179 insertions, 0 deletions
diff --git a/portmidi/pm_mac/pmmacosxcm.c b/portmidi/pm_mac/pmmacosxcm.c new file mode 100755 index 0000000..e8b196c --- /dev/null +++ b/portmidi/pm_mac/pmmacosxcm.c @@ -0,0 +1,1179 @@ +/* + * Platform interface to the MacOS X CoreMIDI framework + * + * Jon Parise <jparise at cmu.edu> + * and subsequent work by Andrew Zeldis and Zico Kolter + * and Roger B. Dannenberg + * + * $Id: pmmacosx.c,v 1.17 2002/01/27 02:40:40 jon Exp $ + */ + +/* Notes: + + Since the input and output streams are represented by + MIDIEndpointRef values and almost no other state, we store the + MIDIEndpointRef on pm_descriptors[midi->device_id].descriptor. + + OS X does not seem to have an error-code-to-text function, so we + will just use text messages instead of error codes. + + Virtual device input synchronization: Once we create a virtual + device, it is always "on" and receiving messages, but it must drop + messages unless the device has been opened with Pm_OpenInput. To + open, the main thread should create all the data structures, then + call OSMemoryBarrier so that writes are observed, then set + is_opened = TRUE. To close without locks, we need to get the + callback to set is_opened to FALSE before we free data structures; + otherwise, there's a race condition where closing could delete + structures in use by the virtual_read_callback function. We send + 8 MIDI resets (FF) in a single packet to our own port to signal + the virtual_read_callback to close it. Then, we wait for the + callback to recognize the "close" packet and reset is_opened. + + Device scanning is done when you first open an application. + PortMIDI does not actively update the devices. Instead, you must + Pm_Terminate() and Pm_Initialize(), basically starting over. But + CoreMIDI does not have a way to shut down(!), and even + MIDIClientDispose() somehow retains state (and docs say do not + call it even if it worked). The solution, apparently, is to + call CFRunLoopRunInMode(), which somehow updates CoreMIDI + state. + + But when do we call CFRunLoopRunInMode()? I tried calling it + in midi_in_poll() which is called when you call Pm_Read() since + that is called often. I observed that this caused the program + to block for as long as 50ms and fairly often for 2 or 3ms. + What was Apple thinking? Is it really OK to design systems that + can only function with a tricky multi-threaded, non-blocking + priority-based solution, and then not provide a proof of concept + or documentation? Or is Apple's design really flawed? If anyone + at Apple reads this, please let me know -- I'm curious. + + But I digress... Here's the PortMidi approach: Since + CFRunLoopRunInMode() is potentially a non-realtime operation, + we only call it in Pm_Initialize(), where other calls to look + up devices and device names are quite slow to begin with. Again, + PortMidi does not actively scan for new or deleted devices, so + if devices change, you won't see it until the next Pm_Terminate + and Pm_Initialize. + + Calling CFRunLoopRunInMode() once is probably not enough. There + might be better way, but it seems to work to just call it 100 + times and insert 20 1ms delays (in case some inter-process + communication or synchronization is going on). + This adds 20ms to the wall time of Pm_Initialize(), but it + typically runs 30ms to much more (~4s), so this has little impact. + */ + +#include <stdlib.h> + +/* turn on lots of debugging print statements */ +#define CM_DEBUG if (0) +/* #define CM_DEBUG if (1) */ + +#include "portmidi.h" +#include "pmutil.h" +#include "pminternal.h" +#include "porttime.h" +#include "pmmacosxcm.h" + +#include <stdio.h> +#include <string.h> + +#include <CoreServices/CoreServices.h> +#include <CoreMIDI/MIDIServices.h> +#include <CoreAudio/HostTime.h> +#include <unistd.h> +#include <libkern/OSAtomic.h> + +#define PACKET_BUFFER_SIZE 1024 +/* maximum overall data rate (OS X limits MIDI rate in case there + * is a cycle among IAC ports. + */ + +#define MAX_BYTES_PER_S 5400 + +/* Apple reports that packets are dropped when the MIDI bytes/sec + exceeds 15000. This is computed by "tracking the number of MIDI + bytes scheduled into 1-second buckets over the last six seconds and + averaging these counts." This was confirmed in measurements + (2021) with pm_test/fast.c and pm_test/fastrcv.c Now, in 2022, with + macOS 12, pm_test/fast{rcv}.c show problems begin at 6000 bytes/sec. + Previously, we set MAX_BYTES_PER_S to 14000. This is reduced to + 5400 based on testing (which shows 5700 is too high) to fix the + packet loss problem that showed up with macOS 12. + + Experiments show this restriction applies to IAC bus MIDI, but not + to hardware interfaces. (I measured 0.5 Mbps each way over USB to a + Teensy 3.2 microcontroller implementing a USB MIDI loopback. Maybe + it would get 1 Mbps one-way, which would make the CoreMIDI + restriction 18x slower than USB. Maybe other USB MIDI + implementations are faster -- USB top speed for other protocols is + certainly higher than 1 Mbps!) + + This is apparently based on timestamps, not on real time, so we + have to avoid constructing packets that schedule high speed output + regardless of when writes occur. The solution is to alter + timestamps to limit data rates. This adds a slight time + distortion, e.g. an 11 note chord with all notes on the same + timestamp will be altered so that the last message is delayed by + 11 messages x 3 bytes/message / 5400 bytes/second = 6.1 ms. + Note that this is about 2x MIDI speed, but at least 18x slower + than USB MIDI. + + Altering timestamps creates another problem, which is that a sender + that exceeds the maximum rate can queue up an unbounded number of + messages. With non-USB MIDI devices, you could be writing 5x faster + to CoreMIDI than the hardware interface can send, causing an + unbounded backlog, not to mention that the output stream will be a + steady byte stream (e.g., one 3-byte MIDI message every 0.55 ms), + losing any original timing or rhythm. PortMidi does not guarantee + delivery if, over the long run, you write faster than the hardware + can send. + + The LIMIT_RATE symbol, if defined (which is the default), enables + code to modify timestamps for output to an IAC device as follows: + + Before a packet is formed, the message timestamp is set to the + maximum of the PortMidi timestamp (converted to CoreMIDI time) + and min_next_time. After each send, min_next_time is updated to + the packet time + packet length * delay_per_byte, which limits + the scheduled bytes-per-second. Also, after each packet list + flush, min_next_time is updated to the maximum of min_next_time + and the real time, which prevents many bytes to be scheduled in + the past. (We could more directly just say packets are never + scheduled in the past, but we prefer to get the current time -- a + system call -- only when we perform the more expensive operation + of flushing packets, so that's when we update min_next_time to + the current real time. If we are sending a lot, we have to flush + a lot, so the time will be updated frequently when it matters.) + + This possible adjustment to timestamps can distort accurate + timestamps by up to 0.556 us per 3-byte MIDI message. + + Nothing blocks the sender from queueing up an arbitrary number of + messages. Timestamps should be used for accurate timing by sending + timestamped messages a little ahead of real time, not for + scheduling an entire MIDI sequence at once! + */ +#define LIMIT_RATE 1 + +#define SYSEX_BUFFER_SIZE 128 +/* What is the maximum PortMidi device number for an IAC device? A + * cleaner design would be to not use the endpoint as our device + * representation. Instead, we could have a private extensible struct + * to keep all device information, including whether the device is + * implemented with the AppleMIDIIACDriver, which we need because we + * have to limit the data rate to this particular driver to avoid + * dropping messages. Rather than rewrite a lot of code, I am just + * allocating 64 bytes to flag which devices are IAC ones. If an IAC + * device number is greater than 63, PortMidi will fail to limit + * writes to it, but will not complain and will not access memory + * outside the 64-element array of char. + */ +#define MAX_IAC_NUM 63 + +#define VERBOSE_ON 1 +#define VERBOSE if (VERBOSE_ON) + +#define MIDI_SYSEX 0xf0 +#define MIDI_EOX 0xf7 +#define MIDI_CLOCK 0xf8 +#define MIDI_STATUS_MASK 0x80 + +// "Ref"s are pointers on 32-bit machines and ints on 64 bit machines +// NULL_REF is our representation of either 0 or NULL +#ifdef __LP64__ +#define NULL_REF 0 +#else +#define NULL_REF NULL +#endif + +static MIDIClientRef client = NULL_REF; /* Client handle to the MIDI server */ +static MIDIPortRef portIn = NULL_REF; /* Input port handle */ +static MIDIPortRef portOut = NULL_REF; /* Output port handle */ +static char isIAC[MAX_IAC_NUM + 1]; /* is device an IAC device */ + +extern pm_fns_node pm_macosx_in_dictionary; +extern pm_fns_node pm_macosx_out_dictionary; + +typedef struct coremidi_info_struct { + int is_virtual; /* virtual device (TRUE) or actual device (FALSE)? */ + UInt64 delta; /* difference between stream time and real time in ns */ + int sysex_mode; /* middle of sending sysex */ + uint32_t sysex_word; /* accumulate data when receiving sysex */ + uint32_t sysex_byte_count; /* count how many received */ + char error[PM_HOST_ERROR_MSG_LEN]; + char callback_error[PM_HOST_ERROR_MSG_LEN]; + Byte packetBuffer[PACKET_BUFFER_SIZE]; + MIDIPacketList *packetList; /* a pointer to packetBuffer */ + MIDIPacket *packet; + Byte sysex_buffer[SYSEX_BUFFER_SIZE]; /* temp storage for sysex data */ + MIDITimeStamp sysex_timestamp; /* host timestamp to use with sysex data */ + /* allow for running status (is running status possible here? -rbd): -cpr */ + UInt64 min_next_time; /* when can the next send take place? (host time) */ + int isIACdevice; + Float64 us_per_host_tick; /* host clock frequency, units of min_next_time */ + UInt64 host_ticks_per_byte; /* host clock units per byte at maximum rate */ +} coremidi_info_node, *coremidi_info_type; + +/* private function declarations */ +MIDITimeStamp timestamp_pm_to_cm(PmTimestamp timestamp); // returns host time +PmTimestamp timestamp_cm_to_pm(MIDITimeStamp timestamp); // returns ms + +char* cm_get_full_endpoint_name(MIDIEndpointRef endpoint, int *iac_flag); + +static PmError check_hosterror(OSStatus err, const char *msg) +{ + if (err != noErr) { + snprintf(pm_hosterror_text, PM_HOST_ERROR_MSG_LEN, "Host error %ld: %s", (long) err, msg); + pm_hosterror = TRUE; + return pmHostError; + } + return pmNoError; +} + + +static PmTimestamp midi_synchronize(PmInternal *midi) +{ + coremidi_info_type info = (coremidi_info_type) midi->api_info; + UInt64 pm_stream_time_2 = // current time in ns + AudioConvertHostTimeToNanos(AudioGetCurrentHostTime()); + PmTimestamp real_time; // in ms + UInt64 pm_stream_time; // in ns + /* if latency is zero and this is an output, there is no + time reference and midi_synchronize should never be called */ + assert(midi->time_proc); + assert(midi->is_input || midi->latency != 0); + do { + /* read real_time between two reads of stream time */ + pm_stream_time = pm_stream_time_2; + real_time = (*midi->time_proc)(midi->time_info); + pm_stream_time_2 = AudioConvertHostTimeToNanos( + AudioGetCurrentHostTime()); + /* repeat if more than 0.5 ms has elapsed */ + } while (pm_stream_time_2 > pm_stream_time + 500000); + info->delta = pm_stream_time - ((UInt64) real_time * (UInt64) 1000000); + midi->sync_time = real_time; + return real_time; +} + + +/* called when MIDI packets are received */ +static void read_callback(const MIDIPacketList *newPackets, PmInternal *midi) +{ + PmTimestamp timestamp; + MIDIPacket *packet; + unsigned int packetIndex; + uint32_t now; + /* Retrieve the context for this connection */ + coremidi_info_type info = (coremidi_info_type) midi->api_info; + assert(info); + + CM_DEBUG printf("read_callback: numPackets %d: ", newPackets->numPackets); + + /* synchronize time references every 100ms */ + now = (*midi->time_proc)(midi->time_info); + if (midi->first_message || midi->sync_time + 100 /*ms*/ < now) { + /* time to resync */ + now = midi_synchronize(midi); + midi->first_message = FALSE; + } + + packet = (MIDIPacket *) &newPackets->packet[0]; + /* hardware devices get untimed messages and apply timestamps. We + * want to preserve them because they should be more accurate than + * applying the current time here. virtual devices just pass on the + * packet->timeStamp, which could be anything. PortMidi says the + * PortMidi timestamp is the time the message is received. We do not + * know if we are receiving from a device driver or a virtual device. + * PortMidi sends to virtual devices get a current timestamp, so we + * can treat them as the receive time. If the timestamp is zero, + * suggested by CoreMIDI as the value to use for immediate delivery, + * then we plug in `now` which is obtained above. If another + * application sends bogus non-zero timestamps, we will convert them + * to this port's reference time and pass them as event.timestamp. + * Receiver beware. + */ + CM_DEBUG printf("read_callback packet @ %lld ns (host %lld) " + "status %x length %d\n", + AudioConvertHostTimeToNanos(AudioGetCurrentHostTime()), + AudioGetCurrentHostTime(), + packet->data[0], packet->length); + for (packetIndex = 0; packetIndex < newPackets->numPackets; packetIndex++) { + /* Set the timestamp and dispatch this message */ + CM_DEBUG printf(" packet->timeStamp %lld ns %lld host\n", + packet->timeStamp, + AudioConvertHostTimeToNanos(packet->timeStamp)); + if (packet->timeStamp == 0) { + timestamp = now; + } else { + timestamp = (PmTimestamp) /* explicit conversion */ ( + (AudioConvertHostTimeToNanos(packet->timeStamp) - info->delta) / + (UInt64) 1000000); + } + pm_read_bytes(midi, packet->data, packet->length, timestamp); + packet = MIDIPacketNext(packet); + } +} + +/* callback for real devices - redirects to read_callback */ +static void device_read_callback(const MIDIPacketList *newPackets, + void *refCon, void *connRefCon) +{ + read_callback(newPackets, (PmInternal *) connRefCon); +} + + +/* callback for virtual devices - redirects to read_callback */ +static void virtual_read_callback(const MIDIPacketList *newPackets, + void *refCon, void *connRefCon) +{ + /* this refCon is the device ID -- if there is a valid ID and + the pm_descriptors table has a non-null pointer to a PmInternal, + then then device is open and should receive this data */ + PmDeviceID id = (PmDeviceID) (size_t) refCon; + if (id >= 0 && id < pm_descriptor_len) { + if (pm_descriptors[id].pub.opened) { + /* check for close request (7 reset status bytes): */ + if (newPackets->numPackets == 1 && + newPackets->packet[0].length == 8 && + /* CoreMIDI declares packets with 4-byte alignment, so we + * should be safe to test for 8 0xFF's as 2 32-bit values: */ + *(SInt32 *) &newPackets->packet[0].data[0] == -1 && + *(SInt32 *) &newPackets->packet[0].data[4] == -1) { + CM_DEBUG printf("got close request packet\n"); + pm_descriptors[id].pub.opened = FALSE; + return; + } else { + read_callback(newPackets, pm_descriptors[id].pm_internal); + } + } + } +} + + +/* allocate and initialize our internal coremidi connection info */ +static coremidi_info_type create_macosxcm_info(int is_virtual, int is_input) +{ + coremidi_info_type info = (coremidi_info_type) + pm_alloc(sizeof(coremidi_info_node)); + if (!info) { + return NULL; + } + info->is_virtual = is_virtual; + info->delta = 0; + info->sysex_mode = FALSE; + info->sysex_word = 0; + info->sysex_byte_count = 0; + info->packet = NULL; + info->min_next_time = 0; + info->isIACdevice = FALSE; + info->us_per_host_tick = 1000000.0 / AudioGetHostClockFrequency(); + info->host_ticks_per_byte = + (UInt64) (1000000.0 / (info->us_per_host_tick * MAX_BYTES_PER_S)); + info->packetList = (is_input ? NULL : + (MIDIPacketList *) info->packetBuffer); + return info; +} + + +static PmError midi_in_open(PmInternal *midi, void *driverInfo) +{ + MIDIEndpointRef endpoint; + coremidi_info_type info; + OSStatus macHostError; + int is_virtual = pm_descriptors[midi->device_id].pub.is_virtual; + + /* if this is an external device, descriptor is a MIDIEndpointRef. + * if this is a virtual device for this application, descriptor is NULL. + */ + if (!is_virtual) { + endpoint = (MIDIEndpointRef) (intptr_t) + pm_descriptors[midi->device_id].descriptor; + if (endpoint == NULL_REF) { + return pmInvalidDeviceId; + } + } + + info = create_macosxcm_info(is_virtual, TRUE); + midi->api_info = info; + if (!info) { + return pmInsufficientMemory; + } + if (!is_virtual) { + macHostError = MIDIPortConnectSource(portIn, endpoint, midi); + if (macHostError != noErr) { + midi->api_info = NULL; + pm_free(info); + return check_hosterror(macHostError, + "MIDIPortConnectSource() in midi_in_open()"); + } + } + return pmNoError; +} + +static PmError midi_in_close(PmInternal *midi) +{ + MIDIEndpointRef endpoint; + OSStatus macHostError; + PmError err = pmNoError; + + coremidi_info_type info = (coremidi_info_type) midi->api_info; + + if (!info) return pmBadPtr; + + endpoint = (MIDIEndpointRef) (intptr_t) + pm_descriptors[midi->device_id].descriptor; + if (endpoint == NULL_REF) { + return pmBadPtr; + } + + if (!info->is_virtual) { + /* shut off the incoming messages before freeing data structures */ + macHostError = MIDIPortDisconnectSource(portIn, endpoint); + /* If the source closes, you get paramErr == -50 here. It seems + * possible to monitor changes like sources closing by getting + * notifications ALL changes, but the CoreMIDI documentation is + * really terrible overall, and it seems easier to just ignore + * this host error. + */ + if (macHostError != noErr && macHostError != -50) { + pm_hosterror = TRUE; + err = check_hosterror(macHostError, + "MIDIPortDisconnectSource() in midi_in_close()"); + } + } else { + /* make "close virtual port" message */ + SInt64 close_port_bytes = 0xFFFFFFFFFFFFFFFF; + /* memory requirements: packet count (4), timestamp (8), length (2), + * data (8). Total: 22, but we allocate plenty more: + */ + Byte packetBuffer[64]; + MIDIPacketList *plist = (MIDIPacketList *) packetBuffer; + MIDIPacket *packet = MIDIPacketListInit(plist); + MIDIPacketListAdd(plist, 64, packet, 0, 8, + (const Byte *) &close_port_bytes); + macHostError = MIDISend(portOut, endpoint, plist); + if (macHostError != noErr) { + err = check_hosterror(macHostError, "MIDISend() (PortMidi close " + "port packet) in midi_in_close()"); + } + /* when packet is delivered, callback thread will clear opened; + * we must wait for that before removing the input queues etc. + * Maybe this could use signals of some kind, but if signals use + * locks, locks can cause priority inversion problems, so we will + * just sleep as needed. On the MIDI timescale, inserting a 0.5ms + * latency should be OK, as the application has no business + * opening/closing devices during time-critical moments. + * + * We expect the MIDI thread to close the device quickly (<0.5ms), + * but we wait up to 50ms in case something terrible happens like + * getting paged out in the middle of deliving packets to this + * virtual device. If there is still no response, we time out and + * force the close without the MIDI thread (even this will probably + * succeed - the problem would be: this thread proceeds to delete + * the input queues, and the freed memory is reallocated and + * overwritten so that queues are no longer usable. Meanwhile, + * the MIDI thread has already begun to deliver packets, so the + * check for opened == TRUE passed, but MIDI thread does not insert + * into queue until queue is freed, reallocated and overwritten. + */ + for (int i = 0; i < 100; i++) { /* up to 50ms delay */ + if (!pm_descriptors[midi->device_id].pub.opened) { + break; + } + usleep(500); /* 0.5ms */ + } + pm_descriptors[midi->device_id].pub.opened = FALSE; /* force it */ + } + midi->api_info = NULL; + pm_free(info); + return err; +} + + +static PmError midi_out_open(PmInternal *midi, void *driverInfo) +{ + coremidi_info_type info; + int is_virtual = pm_descriptors[midi->device_id].pub.is_virtual; + + info = create_macosxcm_info(is_virtual, FALSE); + if (midi->device_id <= MAX_IAC_NUM) { + info->isIACdevice = isIAC[midi->device_id]; + CM_DEBUG printf("midi_out_open isIACdevice %d\n", info->isIACdevice); + } + midi->api_info = info; + if (!info) { + return pmInsufficientMemory; + } + return pmNoError; +} + + +static PmError midi_out_close(PmInternal *midi) +{ + coremidi_info_type info = (coremidi_info_type) midi->api_info; + if (!info) return pmBadPtr; + midi->api_info = NULL; + pm_free(info); + return pmNoError; +} + + +/* MIDIDestinationCreate apparently cannot create a virtual device + * without a callback and a "refCon" parameter, but when we create + * a virtual device, we do not want a PortMidi stream yet -- that + * should wait for the user to open the stream. So, for the refCon, + * use the PortMidi device ID. The callback will check if the + * device is opened within PortMidi, and if so, use the pm_descriptors + * table to locate the corresponding PmStream. + */ +static PmError midi_create_virtual(int is_input, const char *name, + void *device_info) +{ + OSStatus macHostError; + MIDIEndpointRef endpoint; + CFStringRef nameRef; + PmDeviceID id = pm_add_device("CoreMIDI", name, is_input, TRUE, NULL, + (is_input ? &pm_macosx_in_dictionary : + &pm_macosx_out_dictionary)); + if (id < 0) { /* error -- out of memory or name conflict? */ + return id; + } + + nameRef = CFStringCreateWithCString(NULL, name, kCFStringEncodingUTF8); + if (is_input) { + macHostError = MIDIDestinationCreate(client, nameRef, + virtual_read_callback, (void *) (intptr_t) id, &endpoint); + } else { + macHostError = MIDISourceCreate(client, nameRef, &endpoint); + } + CFRelease(nameRef); + + if (macHostError != noErr) { + /* undo the device we just allocated */ + pm_undo_add_device(id); + return check_hosterror(macHostError, (is_input ? + "MIDIDestinationCreateWithProtocol() in midi_create_virtual()" : + "MIDISourceCreateWithProtocol() in midi_create_virtual()")); + } + + /* Do we have a manufacturer name? If not, set to "PortMidi" */ + const char *mfr_name = "PortMidi"; + PmSysDepInfo *info = (PmSysDepInfo *) device_info; + /* the version where pmKeyCoreMidiManufacturer was introduced is 210 */ + if (info && info->structVersion >= 210) { + int i; + for (i = 0; i < info->length; i++) { /* search for key */ + if (info->properties[i].key == pmKeyCoreMidiManufacturer) { + mfr_name = info->properties[i].value; + break; + } /* no other keys are recognized; they are ignored */ + } + } + nameRef = CFStringCreateWithCString(NULL, mfr_name, kCFStringEncodingUTF8); + MIDIObjectSetStringProperty(endpoint, kMIDIPropertyManufacturer, nameRef); + CFRelease(nameRef); + + pm_descriptors[id].descriptor = (void *) (intptr_t) endpoint; + return id; +} + + +static PmError midi_delete_virtual(PmDeviceID id) +{ + MIDIEndpointRef endpoint; + OSStatus macHostError; + + endpoint = (MIDIEndpointRef) (long) pm_descriptors[id].descriptor; + if (endpoint == NULL_REF) { + return pmBadPtr; + } + macHostError = MIDIEndpointDispose(endpoint); + return check_hosterror(macHostError, + "MIDIEndpointDispose() in midi_in_close()"); +} + + +static PmError midi_abort(PmInternal *midi) +{ + OSStatus macHostError; + MIDIEndpointRef endpoint = (MIDIEndpointRef) (intptr_t) + pm_descriptors[midi->device_id].descriptor; + macHostError = MIDIFlushOutput(endpoint); + return check_hosterror(macHostError, + "MIDIFlushOutput() in midi_abort()"); +} + + +static PmError midi_write_flush(PmInternal *midi, PmTimestamp timestamp) +{ + OSStatus macHostError = 0; + coremidi_info_type info = (coremidi_info_type) midi->api_info; + MIDIEndpointRef endpoint = (MIDIEndpointRef) (intptr_t) + pm_descriptors[midi->device_id].descriptor; + assert(info); + assert(endpoint); + if (info->packet != NULL) { + /* out of space, send the buffer and start refilling it */ + /* update min_next_time each flush to support rate limit */ + UInt64 host_now = AudioGetCurrentHostTime(); + if (host_now > info->min_next_time) + info->min_next_time = host_now; + if (info->is_virtual) { + macHostError = MIDIReceived(endpoint, info->packetList); + } else { + macHostError = MIDISend(portOut, endpoint, info->packetList); + } + info->packet = NULL; /* indicate no data in packetList now */ + } + return check_hosterror(macHostError, (info->is_virtual ? + "MIDIReceived() in midi_write()" : + "MIDISend() in midi_write()")); +} + + +static PmError send_packet(PmInternal *midi, Byte *message, + unsigned int messageLength, MIDITimeStamp timestamp) +{ + PmError err; + coremidi_info_type info = (coremidi_info_type) midi->api_info; + assert(info); + + CM_DEBUG printf("add %d to packet %p len %d timestamp %lld @ %lld ns " + "(host %lld)\n", + message[0], info->packet, messageLength, timestamp, + AudioConvertHostTimeToNanos(AudioGetCurrentHostTime()), + AudioGetCurrentHostTime()); + info->packet = MIDIPacketListAdd(info->packetList, + sizeof(info->packetBuffer), info->packet, + timestamp, messageLength, message); +#if LIMIT_SEND_RATE + info->byte_count += messageLength; +#endif + if (info->packet == NULL) { + /* out of space, send the buffer and start refilling it */ + /* make midi->packet non-null to fool midi_write_flush into sending */ + info->packet = (MIDIPacket *) 4; + /* timestamp is 0 because midi_write_flush ignores timestamp since + * timestamps are already in packets. The timestamp parameter is here + * because other API's need it. midi_write_flush can be called + * from system-independent code that must be cross-API. + */ + if ((err = midi_write_flush(midi, 0)) != pmNoError) return err; + info->packet = MIDIPacketListInit(info->packetList); + assert(info->packet); /* if this fails, it's a programming error */ + info->packet = MIDIPacketListAdd(info->packetList, + sizeof(info->packetBuffer), info->packet, + timestamp, messageLength, message); + assert(info->packet); /* can't run out of space on first message */ + } + return pmNoError; +} + + +static PmError midi_write_short(PmInternal *midi, PmEvent *event) +{ + PmTimestamp when = event->timestamp; + PmMessage what = event->message; + MIDITimeStamp timestamp; + coremidi_info_type info = (coremidi_info_type) midi->api_info; + Byte message[4]; + unsigned int messageLength; + + if (info->packet == NULL) { + info->packet = MIDIPacketListInit(info->packetList); + /* this can never fail, right? failure would indicate something + unrecoverable */ + assert(info->packet); + } + + /* PortMidi specifies that incoming timestamps are the receive + * time. Devices attach their receive times, but virtual devices + * do not. Instead, they pass along whatever timestamp was sent to + * them. We do not know if we are connected to real or virtual + * device. To avoid wild timestamps on the receiving end, we + * consider 2 cases: PortMidi timestamp is zero or latency is + * zero. Both mean send immediately, so we attach the current time + * which will go out immediately and arrive with a sensible + * timestamp (not zero and not zero mapped to the client's local + * time). Otherwise, we assume the timestamp is reasonable. It + * might be slighly in the past, but we pass it along after + * translation to MIDITimeStamp units. + * + * Compute timestamp: use current time if timestamp is zero or + * latency is zero. Both mean no timing and send immediately. + */ + if (when == 0 || midi->latency == 0) { + timestamp = AudioGetCurrentHostTime(); + } else { /* translate PortMidi time + latency to CoreMIDI time */ + timestamp = ((UInt64) (when + midi->latency) * (UInt64) 1000000) + + info->delta; + timestamp = AudioConvertNanosToHostTime(timestamp); + } + + message[0] = Pm_MessageStatus(what); + message[1] = Pm_MessageData1(what); + message[2] = Pm_MessageData2(what); + messageLength = pm_midi_length((int32_t) what); + +#ifdef LIMIT_RATE + /* Make sure we go forward in time. */ + if (timestamp < info->min_next_time) { + timestamp = info->min_next_time; + } + /* Note that if application is way behind and slowly catching up, then + * timestamps could be increasing faster than real time, and since + * timestamps are used to estimate data rate, our estimate could be + * low, causing CoreMIDI to drop packets. This seems very unlikely. + */ + if (info->isIACdevice || info->is_virtual) { + info->min_next_time = timestamp + messageLength * + info->host_ticks_per_byte; + } +#endif + /* Add this message to the packet list */ + return send_packet(midi, message, messageLength, timestamp); +} + + +static PmError midi_begin_sysex(PmInternal *midi, PmTimestamp when) +{ + UInt64 when_ns; + coremidi_info_type info = (coremidi_info_type) midi->api_info; + assert(info); + info->sysex_byte_count = 0; + + /* compute timestamp */ + if (when == 0) when = midi->now; + /* if latency == 0, midi->now is not valid. We will just set it to zero */ + if (midi->latency == 0) when = 0; + when_ns = ((UInt64) (when + midi->latency) * (UInt64) 1000000) + + info->delta; + info->sysex_timestamp = + (MIDITimeStamp) AudioConvertNanosToHostTime(when_ns); + UInt64 now; /* only make system time call when writing a virtual port */ + if (info->is_virtual && info->sysex_timestamp < + (now = AudioGetCurrentHostTime())) { + info->sysex_timestamp = now; + } + + if (info->packet == NULL) { + info->packet = MIDIPacketListInit(info->packetList); + /* this can never fail, right? failure would indicate something + unrecoverable */ + assert(info->packet); + } + return pmNoError; +} + + +static PmError midi_end_sysex(PmInternal *midi, PmTimestamp when) +{ + PmError err; + coremidi_info_type info = (coremidi_info_type) midi->api_info; + assert(info); + +#ifdef LIMIT_RATE + /* make sure we go foreward in time */ + if (info->sysex_timestamp < info->min_next_time) + info->sysex_timestamp = info->min_next_time; + + if (info->isIACdevice) { + info->min_next_time = info->sysex_timestamp + info->sysex_byte_count * + info->host_ticks_per_byte; + } +#endif + + /* now send what's in the buffer */ + err = send_packet(midi, info->sysex_buffer, info->sysex_byte_count, + info->sysex_timestamp); + info->sysex_byte_count = 0; + if (err != pmNoError) { + info->packet = NULL; /* flush everything in the packet list */ + } + return err; +} + + +static PmError midi_write_byte(PmInternal *midi, unsigned char byte, + PmTimestamp timestamp) +{ + coremidi_info_type info = (coremidi_info_type) midi->api_info; + assert(info); + if (info->sysex_byte_count >= SYSEX_BUFFER_SIZE) { + PmError err = midi_end_sysex(midi, timestamp); + if (err != pmNoError) return err; + } + info->sysex_buffer[info->sysex_byte_count++] = byte; + return pmNoError; +} + + +static PmError midi_write_realtime(PmInternal *midi, PmEvent *event) +{ + /* to send a realtime message during a sysex message, first + flush all pending sysex bytes into packet list */ + PmError err = midi_end_sysex(midi, 0); + if (err != pmNoError) return err; + /* then we can just do a normal midi_write_short */ + return midi_write_short(midi, event); +} + + +static unsigned int midi_check_host_error(PmInternal *midi) +{ + return FALSE; +} + + +MIDITimeStamp timestamp_pm_to_cm(PmTimestamp timestamp) +{ + UInt64 nanos; + if (timestamp <= 0) { + return (MIDITimeStamp)0; + } else { + nanos = (UInt64)timestamp * (UInt64)1000000; + return (MIDITimeStamp)AudioConvertNanosToHostTime(nanos); + } +} + + +PmTimestamp timestamp_cm_to_pm(MIDITimeStamp timestamp) +{ + UInt64 nanos; + nanos = AudioConvertHostTimeToNanos(timestamp); + return (PmTimestamp)(nanos / (UInt64)1000000); +} + + +// +// Code taken from http://developer.apple.com/qa/qa2004/qa1374.html +////////////////////////////////////// +// Obtain the name of an endpoint without regard for whether it has connections. +// The result should be released by the caller. +CFStringRef EndpointName(MIDIEndpointRef endpoint, bool isExternal, + int *iac_flag) +{ + CFMutableStringRef result = CFStringCreateMutable(NULL, 0); + CFStringRef str; + *iac_flag = FALSE; + + // begin with the endpoint's name + str = NULL; + MIDIObjectGetStringProperty(endpoint, kMIDIPropertyName, &str); + if (str != NULL) { + CFStringAppend(result, str); + CFRelease(str); + } + MIDIEntityRef entity = NULL_REF; + MIDIEndpointGetEntity(endpoint, &entity); + if (entity == NULL_REF) { + // probably virtual + return result; + } + if (!isExternal) { /* detect IAC devices */ + //extern const CFStringRef kMIDIPropertyDriverOwner; + MIDIObjectGetStringProperty(entity, kMIDIPropertyDriverOwner, &str); + if (str != NULL) { + char s[32]; /* driver name may truncate, but that's OK */ + CFStringGetCString(str, s, 31, kCFStringEncodingUTF8); + s[31] = 0; /* make sure it is terminated just to be safe */ + CM_DEBUG printf("driver %s\n", s); + *iac_flag = (strcmp(s, "com.apple.AppleMIDIIACDriver") == 0); + } + } + + if (CFStringGetLength(result) == 0) { + // endpoint name has zero length -- try the entity + str = NULL; + MIDIObjectGetStringProperty(entity, kMIDIPropertyName, &str); + if (str != NULL) { + CFStringAppend(result, str); + CFRelease(str); + } + } + // now consider the device's name + MIDIDeviceRef device = NULL_REF; + MIDIEntityGetDevice(entity, &device); + if (device == NULL_REF) + return result; + + str = NULL; + MIDIObjectGetStringProperty(device, kMIDIPropertyName, &str); + if (CFStringGetLength(result) == 0) { + CFRelease(result); + return str; + } + if (str != NULL) { + // if an external device has only one entity, throw away + // the endpoint name and just use the device name + if (isExternal && MIDIDeviceGetNumberOfEntities(device) < 2) { + CFRelease(result); + return str; + } else { + if (CFStringGetLength(str) == 0) { + CFRelease(str); + return result; + } + // does the entity name already start with the device name? + // (some drivers do this though they shouldn't) + // if so, do not prepend + if (CFStringCompareWithOptions(result, /* endpoint name */ + str, /* device name */ + CFRangeMake(0, CFStringGetLength(str)), 0) != + kCFCompareEqualTo) { + // prepend the device name to the entity name + if (CFStringGetLength(result) > 0) + CFStringInsert(result, 0, CFSTR(" ")); + CFStringInsert(result, 0, str); + } + CFRelease(str); + } + } + return result; +} + + +// Obtain the name of an endpoint, following connections. +// The result should be released by the caller. +static CFStringRef ConnectedEndpointName(MIDIEndpointRef endpoint, + int *iac_flag) +{ + CFMutableStringRef result = CFStringCreateMutable(NULL, 0); + CFStringRef str; + OSStatus err; + long i; + + // Does the endpoint have connections? + CFDataRef connections = NULL; + long nConnected = 0; + bool anyStrings = false; + err = MIDIObjectGetDataProperty(endpoint, kMIDIPropertyConnectionUniqueID, + &connections); + if (connections != NULL) { + // It has connections, follow them + // Concatenate the names of all connected devices + nConnected = CFDataGetLength(connections) / + (int32_t) sizeof(MIDIUniqueID); + if (nConnected) { + const SInt32 *pid = (const SInt32 *)(CFDataGetBytePtr(connections)); + for (i = 0; i < nConnected; ++i, ++pid) { + MIDIUniqueID id = EndianS32_BtoN(*pid); + MIDIObjectRef connObject; + MIDIObjectType connObjectType; + err = MIDIObjectFindByUniqueID(id, &connObject, + &connObjectType); + if (err == noErr) { + if (connObjectType == kMIDIObjectType_ExternalSource || + connObjectType == kMIDIObjectType_ExternalDestination) { + // Connected to an external device's endpoint (>=10.3) + str = EndpointName((MIDIEndpointRef)(connObject), true, + iac_flag); + } else { + // Connected to an external device (10.2) + // (or something else, catch-all) + str = NULL; + MIDIObjectGetStringProperty(connObject, + kMIDIPropertyName, &str); + } + if (str != NULL) { + if (anyStrings) + CFStringAppend(result, CFSTR(", ")); + else anyStrings = true; + CFStringAppend(result, str); + CFRelease(str); + } + } + } + } + CFRelease(connections); + } + if (anyStrings) + return result; // caller should release result + + CFRelease(result); + + // Here, either the endpoint had no connections, or we failed to + // obtain names for any of them. + return EndpointName(endpoint, false, iac_flag); +} + + +char *cm_get_full_endpoint_name(MIDIEndpointRef endpoint, int *iac_flag) +{ + /* Thanks to Dan Wilcox for fixes for Unicode handling */ + CFStringRef fullName = ConnectedEndpointName(endpoint, iac_flag); + CFIndex utf16_len = CFStringGetLength(fullName) + 1; + CFIndex max_byte_len = CFStringGetMaximumSizeForEncoding( + utf16_len, kCFStringEncodingUTF8) + 1; + char* pmname = (char *) pm_alloc(CFStringGetLength(fullName) + 1); + + /* copy the string into our buffer; note that there may be some wasted + space, but the total waste is not large */ + CFStringGetCString(fullName, pmname, max_byte_len, kCFStringEncodingUTF8); + + /* clean up */ + if (fullName) CFRelease(fullName); + return pmname; +} + + +pm_fns_node pm_macosx_in_dictionary = { + none_write_short, + none_sysex, + none_sysex, + none_write_byte, + none_write_short, + none_write_flush, + none_synchronize, + midi_in_open, + midi_abort, + midi_in_close, + success_poll, + midi_check_host_error +}; + +pm_fns_node pm_macosx_out_dictionary = { + midi_write_short, + midi_begin_sysex, + midi_end_sysex, + midi_write_byte, + midi_write_realtime, + midi_write_flush, + midi_synchronize, + midi_out_open, + midi_abort, + midi_out_close, + success_poll, + midi_check_host_error +}; + + +/* We do nothing with callbacks, but generating the callbacks also + * updates CoreMIDI state. Callback may not be essential, but calling + * the CFRunLoopRunInMode is necessary. + */ +void cm_notify(const MIDINotification *msg, void *refCon) +{ + /* for debugging, trace change notifications: + const char *descr[] = { + "undefined (0)", + "kMIDIMsgSetupChanged", + "kMIDIMsgObjectAdded", + "kMIDIMsgObjectRemoved", + "kMIDIMsgPropertyChanged", + "kMIDIMsgThruConnectionsChanged", + "kMIDIMsgSerialPortOwnerChanged", + "kMIDIMsgIOError"}; + + printf("MIDI Notify, messageID %d (%s)\n", (int) msg->messageID, + descr[(int) msg->messageID]); + */ + return; +} + + +PmError pm_macosxcm_init(void) +{ + ItemCount numInputs, numOutputs, numDevices; + MIDIEndpointRef endpoint; + OSStatus macHostError = noErr; + char *error_text; + + memset(isIAC, 0, sizeof(isIAC)); /* initialize all FALSE */ + + /* Register interface CoreMIDI with create_virtual fn */ + pm_add_interf("CoreMIDI", &midi_create_virtual, &midi_delete_virtual); + /* no check for error return because this always succeeds */ + + /* Determine the number of MIDI devices on the system */ + numDevices = MIDIGetNumberOfDevices(); + + /* Return prematurely if no devices exist on the system + Note that this is not an error. There may be no devices. + Pm_CountDevices() will return zero, which is correct and + useful information + */ + if (numDevices <= 0) { + return pmNoError; + } + + /* Initialize the client handle */ + if (client == NULL_REF) { + macHostError = MIDIClientCreate(CFSTR("PortMidi"), &cm_notify, NULL, + &client); + } else { /* see notes above on device scanning */ + for (int i = 0; i < 100; i++) { + // look for any changes before scanning for devices + CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0, true); + if (i % 5 == 0) Pt_Sleep(1); /* insert 20 delays */ + } + } + if (macHostError != noErr) { + error_text = "MIDIClientCreate() in pm_macosxcm_init()"; + goto error_return; + } + numInputs = MIDIGetNumberOfSources(); + numOutputs = MIDIGetNumberOfDestinations(); + + /* Create the input port */ + macHostError = MIDIInputPortCreate(client, CFSTR("Input port"), + device_read_callback, NULL, &portIn); + if (macHostError != noErr) { + error_text = "MIDIInputPortCreate() in pm_macosxcm_init()"; + goto error_return; + } + + /* Create the output port */ + macHostError = MIDIOutputPortCreate(client, CFSTR("Output port"), &portOut); + if (macHostError != noErr) { + error_text = "MIDIOutputPortCreate() in pm_macosxcm_init()"; + goto error_return; + } + + /* Iterate over the MIDI input devices */ + for (int i = 0; i < numInputs; i++) { + int iac_flag; + endpoint = MIDIGetSource(i); + if (endpoint == NULL_REF) { + continue; + } + /* Register this device with PortMidi */ + pm_add_device("CoreMIDI", + cm_get_full_endpoint_name(endpoint, &iac_flag), TRUE, FALSE, + (void *) (intptr_t) endpoint, &pm_macosx_in_dictionary); + } + + /* Iterate over the MIDI output devices */ + for (int i = 0; i < numOutputs; i++) { + int iac_flag; + PmDeviceID id; + endpoint = MIDIGetDestination(i); + if (endpoint == NULL_REF) { + continue; + } + /* Register this device with PortMidi */ + id = pm_add_device("CoreMIDI", + cm_get_full_endpoint_name(endpoint, &iac_flag), FALSE, FALSE, + (void *) (intptr_t) endpoint, &pm_macosx_out_dictionary); + /* if this is an IAC device, tuck that info away for write functions */ + if (iac_flag && id <= MAX_IAC_NUM) { + isIAC[id] = TRUE; + } + } + return pmNoError; + +error_return: + pm_macosxcm_term(); /* clear out any opened ports */ + return check_hosterror(macHostError, error_text); +} + +void pm_macosxcm_term(void) +{ + /* docs say do not explicitly dispose of client + if (client != NULL_REF) MIDIClientDispose(client); */ + if (portIn != NULL_REF) MIDIPortDispose(portIn); + if (portOut != NULL_REF) MIDIPortDispose(portOut); +} |