midiFileParser.c File Reference

Data Structures
struct	midiTrackState
	Contains all track-specific parsing state. More...
struct	midiSaveState_t

Macros
#define	TRK_REMAIN()   (track->track->length - (track->cur - track->track->data))
#define	ERR()

Functions
bool	loadMidiFile (const char *name, midiFile_t *file, bool spiRam)
	Load a MIDI file from the filesystem.
void	unloadMidiFile (midiFile_t *file)
	Free the data associated with the given MIDI file.
bool	initMidiParser (midiFileReader_t *reader, const midiFile_t *file)
	Initialize or reset the MIDI file reader with a particular file.
void	midiParserSetFile (midiFileReader_t *reader, const midiFile_t *file)
	Set a new file for the MIDI file reader. The reader's state will be reset.
void	resetMidiParser (midiFileReader_t *reader)
	Reset the state of the MIDI parser without deinitializing it or changing the file.
void	deinitMidiParser (midiFileReader_t *reader)
	Deinitialize the MIDI file reader and free any memory it has allocated.
bool	midiNextEvent (midiFileReader_t *reader, midiEvent_t *event)
	Process and retrieve the next MIDI event in the file.
void *	globalMidiSave (void)
	Stop all MIDI playback and return a pointer containing the full playback state. This state must be passed to globalMidiRestore() later to restore the previous state.
void	globalMidiRestore (void *data)
	Resume MIDI playback from the state stored in the given pointer. The data will be freed after this call and cannot be reused.
int	midiWriteEvent (uint8_t *out, int max, const midiEvent_t *event)
	Writes a MIDI event to a byte buffer.

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Data Structure Documentation

midiTrackState

struct midiTrackState

Data Fields
const midiTrack_t *	track	A pointer to the MIDI track itself.
const uint8_t *	cur	The pointer to the current offset within this chunk.
uint32_t	time	The accumulated delta times for this track, which nextEvent is relative to.
bool	eventParsed	True if the next event in this channel has already been parsed.
midiEvent_t	nextEvent	The next event, when eventParsed is true.
uint8_t	runningStatus	The last applicable running status command, or 0 if none.
bool	done	Whether or not the END OF TRACK event has been read.

midiSaveState_t

struct midiSaveState_t

Data Fields
midiPlayer_t	player
uint8_t	trackCount
midiTrackState_t *	trackStates

Macro Definition Documentation

TRK_REMAIN

#define TRK_REMAIN

(

)

(track->track->length - (track->cur - track->track->data))

ERR

#define ERR

(

)

Value:

    do                                                                                                         \
    {                                                                                                          \
        track->eventParsed         = false;                                                                    \
        track->nextEvent.deltaTime = UINT32_MAX;                                                               \
        ESP_LOGE("MIDIParser", "Error parsing at line %d and offset %" PRIuPTR " (total offset %" PRIuPTR ")", \
                 __LINE__, (track->cur - track->track->data), (track->cur - reader->file->data));              \
        return false;                                                                                          \
    } while (0)

Function Documentation

loadMidiFile()

bool loadMidiFile	(	const char *	name,
		midiFile_t *	file,
		bool	spiRam )

Load a MIDI file from the filesystem.

Parameters

file	A pointer to a midiFile_t struct to load the file into
name	The name of the MIDI file to load
spiRam	Whether to load the MIDI file into SPIRAM

Returns

true If the load succeeded

false If the load failed

unloadMidiFile()

void unloadMidiFile

(

midiFile_t *

file

)

Free the data associated with the given MIDI file.

Parameters

file	A pointer to the MIDI file to be unloaded

initMidiParser()

bool initMidiParser	(	midiFileReader_t *	reader,
		const midiFile_t *	file )

Initialize or reset the MIDI file reader with a particular file.

Parameters

reader	A pointer to the MIDI file reader to initialize
file	A pointer to the MIDI file to load

Returns

true if the MIDI file reader was initialized

false if an error occurred while allocating data for the MIDI file reader

midiParserSetFile()

void midiParserSetFile	(	midiFileReader_t *	reader,
		const midiFile_t *	file )

Set a new file for the MIDI file reader. The reader's state will be reset.

Parameters

reader	A pointer to the MIDI file reader to set the file of
file	A pointer to the MIDI file to load

resetMidiParser()

void resetMidiParser

(

midiFileReader_t *

reader

)

Reset the state of the MIDI parser without deinitializing it or changing the file.

The next event returned from this MIDI parser will be the first event in the file again.

Parameters

reader

A pointer to the MIDI file reader to reset

deinitMidiParser()

void deinitMidiParser

(

midiFileReader_t *

reader

)

Deinitialize the MIDI file reader and free any memory it has allocated.

Parameters

reader

The MIDI file reader to deinitialize

midiNextEvent()

bool midiNextEvent	(	midiFileReader_t *	reader,
		midiEvent_t *	event )

Process and retrieve the next MIDI event in the file.

Parameters

reader	The reader to read the event from
event	A pointer to a MIDI event to be updated with the next event

Returns

true If event data was written to event

false If there are no more events in this file or there was a fatal parse error

globalMidiSave()

void * globalMidiSave

(

void

)

Stop all MIDI playback and return a pointer containing the full playback state. This state must be passed to globalMidiRestore() later to restore the previous state.

Returns

void* A void-pointer containing the full MIDI playback state

globalMidiRestore()

void globalMidiRestore

(

void *

data

)

Resume MIDI playback from the state stored in the given pointer. The data will be freed after this call and cannot be reused.

Parameters

data	The playback state data returned by globalMidiSave()

midiWriteEvent()

int midiWriteEvent	(	uint8_t *	out,
		int	max,
		const midiEvent_t *	event )

Writes a MIDI event to a byte buffer.

Parameters

out	The byte array
max	The maximum number of bytes to write
event	The event to write

Returns

int The number of bytes written