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Diffstat (limited to 'libs/backends/wavesaudio/portmidi/portmidi.h')
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diff --git a/libs/backends/wavesaudio/portmidi/portmidi.h b/libs/backends/wavesaudio/portmidi/portmidi.h new file mode 100644 index 0000000000..e07991e0d6 --- /dev/null +++ b/libs/backends/wavesaudio/portmidi/portmidi.h @@ -0,0 +1,654 @@ +#ifndef PORT_MIDI_H +#define PORT_MIDI_H +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ + +/* + * PortMidi Portable Real-Time MIDI Library + * PortMidi API Header File + * Latest version available at: http://sourceforge.net/projects/portmedia + * + * Copyright (c) 1999-2000 Ross Bencina and Phil Burk + * Copyright (c) 2001-2006 Roger B. Dannenberg + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files + * (the "Software"), to deal in the Software without restriction, + * including without limitation the rights to use, copy, modify, merge, + * publish, distribute, sublicense, and/or sell copies of the Software, + * and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR + * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF + * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +/* + * The text above constitutes the entire PortMidi license; however, + * the PortMusic community also makes the following non-binding requests: + * + * Any person wishing to distribute modifications to the Software is + * requested to send the modifications to the original developer so that + * they can be incorporated into the canonical version. It is also + * requested that these non-binding requests be included along with the + * license above. + */ + +/* CHANGELOG FOR PORTMIDI + * (see ../CHANGELOG.txt) + * + * NOTES ON HOST ERROR REPORTING: + * + * PortMidi errors (of type PmError) are generic, system-independent errors. + * When an error does not map to one of the more specific PmErrors, the + * catch-all code pmHostError is returned. This means that PortMidi has + * retained a more specific system-dependent error code. The caller can + * get more information by calling Pm_HasHostError() to test if there is + * a pending host error, and Pm_GetHostErrorText() to get a text string + * describing the error. Host errors are reported on a per-device basis + * because only after you open a device does PortMidi have a place to + * record the host error code. I.e. only + * those routines that receive a (PortMidiStream *) argument check and + * report errors. One exception to this is that Pm_OpenInput() and + * Pm_OpenOutput() can report errors even though when an error occurs, + * there is no PortMidiStream* to hold the error. Fortunately, both + * of these functions return any error immediately, so we do not really + * need per-device error memory. Instead, any host error code is stored + * in a global, pmHostError is returned, and the user can call + * Pm_GetHostErrorText() to get the error message (and the invalid stream + * parameter will be ignored.) The functions + * pm_init and pm_term do not fail or raise + * errors. The job of pm_init is to locate all available devices so that + * the caller can get information via PmDeviceInfo(). If an error occurs, + * the device is simply not listed as available. + * + * Host errors come in two flavors: + * a) host error + * b) host error during callback + * These can occur w/midi input or output devices. (b) can only happen + * asynchronously (during callback routines), whereas (a) only occurs while + * synchronously running PortMidi and any resulting system dependent calls. + * Both (a) and (b) are reported by the next read or write call. You can + * also query for asynchronous errors (b) at any time by calling + * Pm_HasHostError(). + * + * NOTES ON COMPILE-TIME SWITCHES + * + * DEBUG assumes stdio and a console. Use this if you want automatic, simple + * error reporting, e.g. for prototyping. If you are using MFC or some + * other graphical interface with no console, DEBUG probably should be + * undefined. + * PM_CHECK_ERRORS more-or-less takes over error checking for return values, + * stopping your program and printing error messages when an error + * occurs. This also uses stdio for console text I/O. + */ + +#ifndef WIN32 +// Linux and OS X have stdint.h +#include <stdint.h> +#else +#ifndef INT32_DEFINED +// rather than having users install a special .h file for windows, +// just put the required definitions inline here. porttime.h uses +// these too, so the definitions are (unfortunately) duplicated there +typedef int int32_t; +typedef unsigned int uint32_t; +#define INT32_DEFINED +#endif +#endif + +#ifdef _WINDLL +#define PMEXPORT __declspec(dllexport) +#else +#define PMEXPORT +#endif + +#ifndef FALSE + #define FALSE 0 +#endif +#ifndef TRUE + #define TRUE 1 +#endif + +/* default size of buffers for sysex transmission: */ +#define PM_DEFAULT_SYSEX_BUFFER_SIZE 1024 + +/** List of portmidi errors.*/ +typedef enum { + pmNoError = 0, + pmNoData = 0, /**< A "no error" return that also indicates no data avail. */ + pmGotData = 1, /**< A "no error" return that also indicates data available */ + pmHostError = -10000, + pmInvalidDeviceId, /** out of range or + * output device when input is requested or + * input device when output is requested or + * device is already opened + */ + pmInsufficientMemory, + pmBufferTooSmall, + pmBufferOverflow, + pmBadPtr, /* PortMidiStream parameter is NULL or + * stream is not opened or + * stream is output when input is required or + * stream is input when output is required */ + pmBadData, /** illegal midi data, e.g. missing EOX */ + pmInternalError, + pmBufferMaxSize /** buffer is already as large as it can be */ + /* NOTE: If you add a new error type, be sure to update Pm_GetErrorText() */ +} PmError; + +/** + Pm_Initialize() is the library initialisation function - call this before + using the library. +*/ +PMEXPORT PmError Pm_Initialize( void ); + +/** + Pm_Terminate() is the library termination function - call this after + using the library. +*/ +PMEXPORT PmError Pm_Terminate( void ); + +/** A single PortMidiStream is a descriptor for an open MIDI device. +*/ +typedef void PortMidiStream; +#define PmStream PortMidiStream + +/** + Test whether stream has a pending host error. Normally, the client finds + out about errors through returned error codes, but some errors can occur + asynchronously where the client does not + explicitly call a function, and therefore cannot receive an error code. + The client can test for a pending error using Pm_HasHostError(). If true, + the error can be accessed and cleared by calling Pm_GetErrorText(). + Errors are also cleared by calling other functions that can return + errors, e.g. Pm_OpenInput(), Pm_OpenOutput(), Pm_Read(), Pm_Write(). The + client does not need to call Pm_HasHostError(). Any pending error will be + reported the next time the client performs an explicit function call on + the stream, e.g. an input or output operation. Until the error is cleared, + no new error codes will be obtained, even for a different stream. +*/ +PMEXPORT int Pm_HasHostError( PortMidiStream * stream ); + + +/** Translate portmidi error number into human readable message. + These strings are constants (set at compile time) so client has + no need to allocate storage +*/ +PMEXPORT const char *Pm_GetErrorText( PmError errnum ); + +/** Translate portmidi host error into human readable message. + These strings are computed at run time, so client has to allocate storage. + After this routine executes, the host error is cleared. +*/ +PMEXPORT void Pm_GetHostErrorText(char * msg, unsigned int len); + +#define HDRLENGTH 50 +#define PM_HOST_ERROR_MSG_LEN 256u /* any host error msg will occupy less + than this number of characters */ + +/** + Device enumeration mechanism. + + Device ids range from 0 to Pm_CountDevices()-1. + +*/ +typedef int PmDeviceID; +#define pmNoDevice -1 +typedef struct { + int structVersion; /**< this internal structure version */ + const char *interf; /**< underlying MIDI API, e.g. MMSystem or DirectX */ + const char *name; /**< device name, e.g. USB MidiSport 1x1 */ + int input; /**< true iff input is available */ + int output; /**< true iff output is available */ + int opened; /**< used by generic PortMidi code to do error checking on arguments */ + +} PmDeviceInfo; + +/** Get devices count, ids range from 0 to Pm_CountDevices()-1. */ +PMEXPORT int Pm_CountDevices( void ); +/** + Pm_GetDefaultInputDeviceID(), Pm_GetDefaultOutputDeviceID() + + Return the default device ID or pmNoDevice if there are no devices. + The result (but not pmNoDevice) can be passed to Pm_OpenMidi(). + + The default device can be specified using a small application + named pmdefaults that is part of the PortMidi distribution. This + program in turn uses the Java Preferences object created by + java.util.prefs.Preferences.userRoot().node("/PortMidi"); the + preference is set by calling + prefs.put("PM_RECOMMENDED_OUTPUT_DEVICE", prefName); + or prefs.put("PM_RECOMMENDED_INPUT_DEVICE", prefName); + + In the statements above, prefName is a string describing the + MIDI device in the form "interf, name" where interf identifies + the underlying software system or API used by PortMdi to access + devices and name is the name of the device. These correspond to + the interf and name fields of a PmDeviceInfo. (Currently supported + interfaces are "MMSystem" for Win32, "ALSA" for Linux, and + "CoreMIDI" for OS X, so in fact, there is no choice of interface.) + In "interf, name", the strings are actually substrings of + the full interface and name strings. For example, the preference + "Core, Sport" will match a device with interface "CoreMIDI" + and name "In USB MidiSport 1x1". It will also match "CoreMIDI" + and "In USB MidiSport 2x2". The devices are enumerated in device + ID order, so the lowest device ID that matches the pattern becomes + the default device. Finally, if the comma-space (", ") separator + between interface and name parts of the preference is not found, + the entire preference string is interpreted as a name, and the + interface part is the empty string, which matches anything. + + On the MAC, preferences are stored in + /Users/$NAME/Library/Preferences/com.apple.java.util.prefs.plist + which is a binary file. In addition to the pmdefaults program, + there are utilities that can read and edit this preference file. + + On the PC, + + On Linux, + +*/ +PMEXPORT PmDeviceID Pm_GetDefaultInputDeviceID( void ); +/** see PmDeviceID Pm_GetDefaultInputDeviceID() */ +PMEXPORT PmDeviceID Pm_GetDefaultOutputDeviceID( void ); + +/** + PmTimestamp is used to represent a millisecond clock with arbitrary + start time. The type is used for all MIDI timestampes and clocks. +*/ +typedef int32_t PmTimestamp; +typedef PmTimestamp (*PmTimeProcPtr)(void *time_info); + +/** TRUE if t1 before t2 */ +#define PmBefore(t1,t2) ((t1-t2) < 0) +/** + \defgroup grp_device Input/Output Devices Handling + @{ +*/ +/** + Pm_GetDeviceInfo() returns a pointer to a PmDeviceInfo structure + referring to the device specified by id. + If id is out of range the function returns NULL. + + The returned structure is owned by the PortMidi implementation and must + not be manipulated or freed. The pointer is guaranteed to be valid + between calls to Pm_Initialize() and Pm_Terminate(). +*/ +PMEXPORT const PmDeviceInfo* Pm_GetDeviceInfo( PmDeviceID id ); + +/** + Pm_OpenInput() and Pm_OpenOutput() open devices. + + stream is the address of a PortMidiStream pointer which will receive + a pointer to the newly opened stream. + + inputDevice is the id of the device used for input (see PmDeviceID above). + + inputDriverInfo is a pointer to an optional driver specific data structure + containing additional information for device setup or handle processing. + inputDriverInfo is never required for correct operation. If not used + inputDriverInfo should be NULL. + + outputDevice is the id of the device used for output (see PmDeviceID above.) + + outputDriverInfo is a pointer to an optional driver specific data structure + containing additional information for device setup or handle processing. + outputDriverInfo is never required for correct operation. If not used + outputDriverInfo should be NULL. + + For input, the buffersize specifies the number of input events to be + buffered waiting to be read using Pm_Read(). For output, buffersize + specifies the number of output events to be buffered waiting for output. + (In some cases -- see below -- PortMidi does not buffer output at all + and merely passes data to a lower-level API, in which case buffersize + is ignored.) + + latency is the delay in milliseconds applied to timestamps to determine + when the output should actually occur. (If latency is < 0, 0 is assumed.) + If latency is zero, timestamps are ignored and all output is delivered + immediately. If latency is greater than zero, output is delayed until the + message timestamp plus the latency. (NOTE: the time is measured relative + to the time source indicated by time_proc. Timestamps are absolute, + not relative delays or offsets.) In some cases, PortMidi can obtain + better timing than your application by passing timestamps along to the + device driver or hardware. Latency may also help you to synchronize midi + data to audio data by matching midi latency to the audio buffer latency. + + time_proc is a pointer to a procedure that returns time in milliseconds. It + may be NULL, in which case a default millisecond timebase (PortTime) is + used. If the application wants to use PortTime, it should start the timer + (call Pt_Start) before calling Pm_OpenInput or Pm_OpenOutput. If the + application tries to start the timer *after* Pm_OpenInput or Pm_OpenOutput, + it may get a ptAlreadyStarted error from Pt_Start, and the application's + preferred time resolution and callback function will be ignored. + time_proc result values are appended to incoming MIDI data, and time_proc + times are used to schedule outgoing MIDI data (when latency is non-zero). + + time_info is a pointer passed to time_proc. + + Example: If I provide a timestamp of 5000, latency is 1, and time_proc + returns 4990, then the desired output time will be when time_proc returns + timestamp+latency = 5001. This will be 5001-4990 = 11ms from now. + + return value: + Upon success Pm_Open() returns PmNoError and places a pointer to a + valid PortMidiStream in the stream argument. + If a call to Pm_Open() fails a nonzero error code is returned (see + PMError above) and the value of port is invalid. + + Any stream that is successfully opened should eventually be closed + by calling Pm_Close(). + +*/ +PMEXPORT PmError Pm_OpenInput( PortMidiStream** stream, + PmDeviceID inputDevice, + void *inputDriverInfo, + int32_t bufferSize, + PmTimeProcPtr time_proc, + void *time_info ); + +PMEXPORT PmError Pm_OpenOutput( PortMidiStream** stream, + PmDeviceID outputDevice, + void *outputDriverInfo, + int32_t bufferSize, + PmTimeProcPtr time_proc, + void *time_info, + int32_t latency ); + /** @} */ + +/** + \defgroup grp_events_filters Events and Filters Handling + @{ +*/ + +/* \function PmError Pm_SetFilter( PortMidiStream* stream, int32_t filters ) + Pm_SetFilter() sets filters on an open input stream to drop selected + input types. By default, only active sensing messages are filtered. + To prohibit, say, active sensing and sysex messages, call + Pm_SetFilter(stream, PM_FILT_ACTIVE | PM_FILT_SYSEX); + + Filtering is useful when midi routing or midi thru functionality is being + provided by the user application. + For example, you may want to exclude timing messages (clock, MTC, start/stop/continue), + while allowing note-related messages to pass. + Or you may be using a sequencer or drum-machine for MIDI clock information but want to + exclude any notes it may play. + */ + +/* Filter bit-mask definitions */ +/** filter active sensing messages (0xFE): */ +#define PM_FILT_ACTIVE (1 << 0x0E) +/** filter system exclusive messages (0xF0): */ +#define PM_FILT_SYSEX (1 << 0x00) +/** filter MIDI clock message (0xF8) */ +#define PM_FILT_CLOCK (1 << 0x08) +/** filter play messages (start 0xFA, stop 0xFC, continue 0xFB) */ +#define PM_FILT_PLAY ((1 << 0x0A) | (1 << 0x0C) | (1 << 0x0B)) +/** filter tick messages (0xF9) */ +#define PM_FILT_TICK (1 << 0x09) +/** filter undefined FD messages */ +#define PM_FILT_FD (1 << 0x0D) +/** filter undefined real-time messages */ +#define PM_FILT_UNDEFINED PM_FILT_FD +/** filter reset messages (0xFF) */ +#define PM_FILT_RESET (1 << 0x0F) +/** filter all real-time messages */ +#define PM_FILT_REALTIME (PM_FILT_ACTIVE | PM_FILT_SYSEX | PM_FILT_CLOCK | \ + PM_FILT_PLAY | PM_FILT_UNDEFINED | PM_FILT_RESET | PM_FILT_TICK) +/** filter note-on and note-off (0x90-0x9F and 0x80-0x8F */ +#define PM_FILT_NOTE ((1 << 0x19) | (1 << 0x18)) +/** filter channel aftertouch (most midi controllers use this) (0xD0-0xDF)*/ +#define PM_FILT_CHANNEL_AFTERTOUCH (1 << 0x1D) +/** per-note aftertouch (0xA0-0xAF) */ +#define PM_FILT_POLY_AFTERTOUCH (1 << 0x1A) +/** filter both channel and poly aftertouch */ +#define PM_FILT_AFTERTOUCH (PM_FILT_CHANNEL_AFTERTOUCH | PM_FILT_POLY_AFTERTOUCH) +/** Program changes (0xC0-0xCF) */ +#define PM_FILT_PROGRAM (1 << 0x1C) +/** Control Changes (CC's) (0xB0-0xBF)*/ +#define PM_FILT_CONTROL (1 << 0x1B) +/** Pitch Bender (0xE0-0xEF*/ +#define PM_FILT_PITCHBEND (1 << 0x1E) +/** MIDI Time Code (0xF1)*/ +#define PM_FILT_MTC (1 << 0x01) +/** Song Position (0xF2) */ +#define PM_FILT_SONG_POSITION (1 << 0x02) +/** Song Select (0xF3)*/ +#define PM_FILT_SONG_SELECT (1 << 0x03) +/** Tuning request (0xF6)*/ +#define PM_FILT_TUNE (1 << 0x06) +/** All System Common messages (mtc, song position, song select, tune request) */ +#define PM_FILT_SYSTEMCOMMON (PM_FILT_MTC | PM_FILT_SONG_POSITION | PM_FILT_SONG_SELECT | PM_FILT_TUNE) + + +PMEXPORT PmError Pm_SetFilter( PortMidiStream* stream, int32_t filters ); + +#define Pm_Channel(channel) (1<<(channel)) +/** + Pm_SetChannelMask() filters incoming messages based on channel. + The mask is a 16-bit bitfield corresponding to appropriate channels. + The Pm_Channel macro can assist in calling this function. + i.e. to set receive only input on channel 1, call with + Pm_SetChannelMask(Pm_Channel(1)); + Multiple channels should be OR'd together, like + Pm_SetChannelMask(Pm_Channel(10) | Pm_Channel(11)) + + Note that channels are numbered 0 to 15 (not 1 to 16). Most + synthesizer and interfaces number channels starting at 1, but + PortMidi numbers channels starting at 0. + + All channels are allowed by default +*/ +PMEXPORT PmError Pm_SetChannelMask(PortMidiStream *stream, int mask); + +/** + Pm_Abort() terminates outgoing messages immediately + The caller should immediately close the output port; + this call may result in transmission of a partial midi message. + There is no abort for Midi input because the user can simply + ignore messages in the buffer and close an input device at + any time. + */ +PMEXPORT PmError Pm_Abort( PortMidiStream* stream ); + +/** + Pm_Close() closes a midi stream, flushing any pending buffers. + (PortMidi attempts to close open streams when the application + exits -- this is particularly difficult under Windows.) +*/ +PMEXPORT PmError Pm_Close( PortMidiStream* stream ); + +/** + Pm_Synchronize() instructs PortMidi to (re)synchronize to the + time_proc passed when the stream was opened. Typically, this + is used when the stream must be opened before the time_proc + reference is actually advancing. In this case, message timing + may be erratic, but since timestamps of zero mean + "send immediately," initialization messages with zero timestamps + can be written without a functioning time reference and without + problems. Before the first MIDI message with a non-zero + timestamp is written to the stream, the time reference must + begin to advance (for example, if the time_proc computes time + based on audio samples, time might begin to advance when an + audio stream becomes active). After time_proc return values + become valid, and BEFORE writing the first non-zero timestamped + MIDI message, call Pm_Synchronize() so that PortMidi can observe + the difference between the current time_proc value and its + MIDI stream time. + + In the more normal case where time_proc + values advance continuously, there is no need to call + Pm_Synchronize. PortMidi will always synchronize at the + first output message and periodically thereafter. +*/ +PmError Pm_Synchronize( PortMidiStream* stream ); + + +/** + Pm_Message() encodes a short Midi message into a 32-bit word. If data1 + and/or data2 are not present, use zero. + + Pm_MessageStatus(), Pm_MessageData1(), and + Pm_MessageData2() extract fields from a 32-bit midi message. +*/ +#define Pm_Message(status, data1, data2) \ + ((((data2) << 16) & 0xFF0000) | \ + (((data1) << 8) & 0xFF00) | \ + ((status) & 0xFF)) +#define Pm_MessageStatus(msg) ((msg) & 0xFF) +#define Pm_MessageData1(msg) (((msg) >> 8) & 0xFF) +#define Pm_MessageData2(msg) (((msg) >> 16) & 0xFF) + +typedef int32_t PmMessage; /**< see PmEvent */ +/** + All midi data comes in the form of PmEvent structures. A sysex + message is encoded as a sequence of PmEvent structures, with each + structure carrying 4 bytes of the message, i.e. only the first + PmEvent carries the status byte. + + Note that MIDI allows nested messages: the so-called "real-time" MIDI + messages can be inserted into the MIDI byte stream at any location, + including within a sysex message. MIDI real-time messages are one-byte + messages used mainly for timing (see the MIDI spec). PortMidi retains + the order of non-real-time MIDI messages on both input and output, but + it does not specify exactly how real-time messages are processed. This + is particulary problematic for MIDI input, because the input parser + must either prepare to buffer an unlimited number of sysex message + bytes or to buffer an unlimited number of real-time messages that + arrive embedded in a long sysex message. To simplify things, the input + parser is allowed to pass real-time MIDI messages embedded within a + sysex message, and it is up to the client to detect, process, and + remove these messages as they arrive. + + When receiving sysex messages, the sysex message is terminated + by either an EOX status byte (anywhere in the 4 byte messages) or + by a non-real-time status byte in the low order byte of the message. + If you get a non-real-time status byte but there was no EOX byte, it + means the sysex message was somehow truncated. This is not + considered an error; e.g., a missing EOX can result from the user + disconnecting a MIDI cable during sysex transmission. + + A real-time message can occur within a sysex message. A real-time + message will always occupy a full PmEvent with the status byte in + the low-order byte of the PmEvent message field. (This implies that + the byte-order of sysex bytes and real-time message bytes may not + be preserved -- for example, if a real-time message arrives after + 3 bytes of a sysex message, the real-time message will be delivered + first. The first word of the sysex message will be delivered only + after the 4th byte arrives, filling the 4-byte PmEvent message field. + + The timestamp field is observed when the output port is opened with + a non-zero latency. A timestamp of zero means "use the current time", + which in turn means to deliver the message with a delay of + latency (the latency parameter used when opening the output port.) + Do not expect PortMidi to sort data according to timestamps -- + messages should be sent in the correct order, and timestamps MUST + be non-decreasing. See also "Example" for Pm_OpenOutput() above. + + A sysex message will generally fill many PmEvent structures. On + output to a PortMidiStream with non-zero latency, the first timestamp + on sysex message data will determine the time to begin sending the + message. PortMidi implementations may ignore timestamps for the + remainder of the sysex message. + + On input, the timestamp ideally denotes the arrival time of the + status byte of the message. The first timestamp on sysex message + data will be valid. Subsequent timestamps may denote + when message bytes were actually received, or they may be simply + copies of the first timestamp. + + Timestamps for nested messages: If a real-time message arrives in + the middle of some other message, it is enqueued immediately with + the timestamp corresponding to its arrival time. The interrupted + non-real-time message or 4-byte packet of sysex data will be enqueued + later. The timestamp of interrupted data will be equal to that of + the interrupting real-time message to insure that timestamps are + non-decreasing. + */ +typedef struct { + PmMessage message; + PmTimestamp timestamp; +} PmEvent; + +/** + @} +*/ +/** \defgroup grp_io Reading and Writing Midi Messages + @{ +*/ +/** + Pm_Read() retrieves midi data into a buffer, and returns the number + of events read. Result is a non-negative number unless an error occurs, + in which case a PmError value will be returned. + + Buffer Overflow + + The problem: if an input overflow occurs, data will be lost, ultimately + because there is no flow control all the way back to the data source. + When data is lost, the receiver should be notified and some sort of + graceful recovery should take place, e.g. you shouldn't resume receiving + in the middle of a long sysex message. + + With a lock-free fifo, which is pretty much what we're stuck with to + enable portability to the Mac, it's tricky for the producer and consumer + to synchronously reset the buffer and resume normal operation. + + Solution: the buffer managed by PortMidi will be flushed when an overflow + occurs. The consumer (Pm_Read()) gets an error message (pmBufferOverflow) + and ordinary processing resumes as soon as a new message arrives. The + remainder of a partial sysex message is not considered to be a "new + message" and will be flushed as well. + +*/ +PMEXPORT int Pm_Read( PortMidiStream *stream, PmEvent *buffer, int32_t length ); + +/** + Pm_Poll() tests whether input is available, + returning TRUE, FALSE, or an error value. +*/ +PMEXPORT PmError Pm_Poll( PortMidiStream *stream); + +/** + Pm_Write() writes midi data from a buffer. This may contain: + - short messages + or + - sysex messages that are converted into a sequence of PmEvent + structures, e.g. sending data from a file or forwarding them + from midi input. + + Use Pm_WriteSysEx() to write a sysex message stored as a contiguous + array of bytes. + + Sysex data may contain embedded real-time messages. +*/ +PMEXPORT PmError Pm_Write( PortMidiStream *stream, PmEvent *buffer, int32_t length ); + +/** + Pm_WriteShort() writes a timestamped non-system-exclusive midi message. + Messages are delivered in order as received, and timestamps must be + non-decreasing. (But timestamps are ignored if the stream was opened + with latency = 0.) +*/ +PMEXPORT PmError Pm_WriteShort( PortMidiStream *stream, PmTimestamp when, int32_t msg); + +/** + Pm_WriteSysEx() writes a timestamped system-exclusive midi message. +*/ +PMEXPORT PmError Pm_WriteSysEx( PortMidiStream *stream, PmTimestamp when, unsigned char *msg); + +/** @} */ + +#ifdef __cplusplus +} +#endif /* __cplusplus */ +#endif /* PORT_MIDI_H */ |