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large journal section parsing (in small buffer)
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@lathoub
lathoub committed Jul 23, 2022
1 parent 0f64273 commit d42ebc8
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Showing 3 changed files with 187 additions and 93 deletions.
38 changes: 27 additions & 11 deletions src/rtpMIDI_Parser.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -21,9 +21,13 @@ class rtpMIDIParser
private:
bool _rtpHeadersComplete = false;
bool _journalSectionComplete = false;
bool _channelJournalSectionComplete = false;
uint16_t midiCommandLength;
uint8_t _journalTotalChannels;
uint8_t rtpMidi_Flags = 0;
int cmdCount = 0;
uint8_t runningstatus = 0;
size_t _bytesToFlush = 0;

public:
AppleMIDISession<UdpClass, Settings, Platform> * session;
Expand All @@ -38,6 +42,15 @@ class rtpMIDIParser
//
parserReturn parse(RtpBuffer_t &buffer)
{
Serial.print("bufferSize: ");
Serial.println(buffer.size());
for (int i = 0; i < buffer.size(); i++)
{
Serial.print(" 0x");
Serial.print(buffer[i], HEX);
}
Serial.println("");

conversionBuffer cb;

// [RFC3550] provides a complete description of the RTP header fields.
Expand All @@ -63,6 +76,8 @@ class rtpMIDIParser

if (_rtpHeadersComplete == false)
{
Serial.println("Parsing header");

auto minimumLen = sizeof(Rtp_t);
if (buffer.size() < minimumLen)
return parserReturn::NotSureGiveMeMoreData;
Expand Down Expand Up @@ -140,29 +155,25 @@ class rtpMIDIParser
midiCommandLength = (midiCommandLength << 8) | octet;
}

cmdCount = 0;
runningstatus = 0;

while (i--)
buffer.pop_front();

_rtpHeadersComplete = true;

// initialize the Journal Section
_journalSectionComplete = false;
_channelJournalSectionComplete = false;
_journalTotalChannels = 0;
}

// Always a MIDI section
if (midiCommandLength > 0)
{
auto retVal = decodeMidiSection(buffer);
switch (retVal) {
case parserReturn::Processed:
break;
case parserReturn::UnexpectedMidiData:
// already processed MIDI data will be played
_rtpHeadersComplete = false;
default:
return retVal;
}
auto retVal = decodeMIDICommandSection(buffer);
if (retVal != parserReturn::Processed) return retVal;
}

// The payload MAY also contain a journal section. The journal section
Expand All @@ -172,10 +183,15 @@ class rtpMIDIParser

if (rtpMidi_Flags & RTP_MIDI_CS_FLAG_J)
{
Serial.println("decoding Journal section");

auto retVal = decodeJournalSection(buffer);
switch (retVal) {
case parserReturn::Processed:
break;
case parserReturn::NotEnoughData:
Serial.println("not enough joournal section");
return parserReturn::NotEnoughData;
case parserReturn::UnexpectedJournalData:
_rtpHeadersComplete = false;
default:
Expand All @@ -190,7 +206,7 @@ class rtpMIDIParser

#include "rtpMIDI_Parser_JournalSection.hpp"

#include "rtpMIDI_Parser_MidiCommandSection.hpp"
#include "rtpMIDI_Parser_CommandSection.hpp"
};

END_APPLEMIDI_NAMESPACE
106 changes: 54 additions & 52 deletions src/rtpMIDI_Parser_MidiCommandSection.hpp → src/rtpMIDI_Parser_CommandSection.hpp
View file
Original file line number Diff line number Diff line change
@@ -1,9 +1,7 @@
// https://www.ietf.org/rfc/rfc4695.html#section-3

parserReturn decodeMidiSection(RtpBuffer_t &buffer)
parserReturn decodeMIDICommandSection(RtpBuffer_t &buffer)
{
int cmdCount = 0;

// https://www.ietf.org/rfc/rfc4695.html#section-3.2
//
// The first MIDI channel command in the MIDI list MUST include a status
Expand Down Expand Up @@ -39,92 +37,90 @@ parserReturn decodeMidiSection(RtpBuffer_t &buffer)
// line.

// (lathoub: RTP_MIDI_CS_FLAG_P((phantom) not implemented

uint8_t runningstatus = 0;

/* Multiple MIDI-commands might follow - the exact number can only be discovered by really decoding the commands! */
while (midiCommandLength)
{
Serial.print("midiCommandLength: ");
Serial.print(midiCommandLength);
Serial.print(" cmdCount: ");
Serial.println(cmdCount);

/* for the first command we only have a delta-time if Z-Flag is set */
if ((cmdCount) || (rtpMidi_Flags & RTP_MIDI_CS_FLAG_Z))
{
auto consumed = decodeTime(buffer);
Serial.println("decoding time");

midiCommandLength -= consumed;
size_t consumed = 0;
auto retVal = decodeTime(buffer, consumed);
if (retVal != parserReturn::Processed) return retVal;

midiCommandLength -= consumed;
while (consumed--)
buffer.pop_front();

if (midiCommandLength > 0 && 0 >= buffer.size())
return parserReturn::NotEnoughData;
}

if (midiCommandLength > 0)
{
/* Decode a MIDI-command - if 0 is returned something went wrong */
size_t consumed = decodeMidi(buffer, runningstatus);
if (consumed == 0)
{
}
else if (consumed > buffer.size())
{
// sysex split in decodeMidi
return parserReturn::NotEnoughData;
}
Serial.println("decoding MIDIcommand section");

cmdCount++;

if (consumed > midiCommandLength) {
buffer.clear();
return parserReturn::UnexpectedMidiData;
size_t consumed = 0;
auto retVal = decodeMidi(buffer, runningstatus, consumed);
if (retVal == parserReturn::NotEnoughData) {
cmdCount = 0; // avoid first command again
return retVal;
}

midiCommandLength -= consumed;

while (consumed--)
buffer.pop_front();

if (midiCommandLength > 0 && 0 >= buffer.size())
return parserReturn::NotEnoughData;

cmdCount++;
}
}

return parserReturn::Processed;
}

size_t decodeTime(RtpBuffer_t &buffer)
parserReturn decodeTime(RtpBuffer_t &buffer, size_t &consumed)
{
uint8_t consumed = 0;
uint32_t deltatime = 0;

/* RTP-MIDI deltatime is "compressed" using only the necessary amount of octets */
for (uint8_t j = 0; j < 4; j++)
{
if (buffer.size() < 1)
return parserReturn::NotEnoughData;

uint8_t octet = buffer[consumed];
deltatime = (deltatime << 7) | (octet & RTP_MIDI_DELTA_TIME_OCTET_MASK);
consumed++;

if ((octet & RTP_MIDI_DELTA_TIME_EXTENSION) == 0)
break;
}
return consumed;

return parserReturn::Processed;
}

size_t decodeMidi(RtpBuffer_t &buffer, uint8_t &runningstatus)
parserReturn decodeMidi(RtpBuffer_t &buffer, uint8_t &runningstatus, size_t &consumed)
{
size_t consumed = 0;
if (buffer.size() < 1)
return parserReturn::NotEnoughData;

auto octet = buffer[0];
auto octet = buffer.front();

/* MIDI realtime-data -> one octet -- unlike serial-wired MIDI realtime-commands in RTP-MIDI will
* not be intermingled with other MIDI-commands, so we handle this case right here and return */
if (octet >= 0xf8)
{
consumed = 1;

session->StartReceivedMidi();
session->ReceivedMidi(buffer[0]);
session->ReceivedMidi(octet);
session->EndReceivedMidi();

return 1;
return parserReturn::Processed;
}

/* see if this first octet is a status message */
Expand All @@ -133,7 +129,7 @@ size_t decodeMidi(RtpBuffer_t &buffer, uint8_t &runningstatus)
/* if we have no running status yet -> error */
if (((runningstatus)&RTP_MIDI_COMMAND_STATUS_FLAG) == 0)
{
return 0;
return parserReturn::Processed;
}
/* our first octet is "virtual" coming from a preceding MIDI-command,
* so actually we have not really consumed anything yet */
Expand All @@ -160,10 +156,8 @@ size_t decodeMidi(RtpBuffer_t &buffer, uint8_t &runningstatus)
/* non-system MIDI-commands encode the command in the high nibble and the channel
* in the low nibble - so we will take care of those cases next */
if (octet < 0xf0)
{
uint8_t type = (octet & 0xf0);

switch (type)
{
switch (octet & 0xf0)
{
case MIDI_NAMESPACE::MidiType::NoteOff:
consumed += 2;
Expand All @@ -188,22 +182,25 @@ size_t decodeMidi(RtpBuffer_t &buffer, uint8_t &runningstatus)
break;
}

if (buffer.size() < consumed)
return parserReturn::NotEnoughData;

session->StartReceivedMidi();
for (size_t j = 0; j < consumed; j++)
session->ReceivedMidi(buffer[j]);
session->EndReceivedMidi();

return consumed;
return parserReturn::Processed;
}

/* Here we catch the remaining system-common commands */
switch (octet)
{
case MIDI_NAMESPACE::MidiType::SystemExclusiveStart:
case MIDI_NAMESPACE::MidiType::SystemExclusiveEnd:
consumed = decodeMidiSysEx(buffer);
if (consumed > buffer.max_size())
return consumed;
consumed = decodeMidiSysEx(buffer, consumed);
// if (consumed > buffer.max_size())
// return consumed;
break;
case MIDI_NAMESPACE::MidiType::TimeCodeQuarterFrame:
consumed += 1;
Expand All @@ -218,17 +215,20 @@ size_t decodeMidi(RtpBuffer_t &buffer, uint8_t &runningstatus)
break;
}

if (buffer.size() < consumed)
return parserReturn::NotEnoughData;

session->StartReceivedMidi();
for (size_t j = 0; j < consumed; j++)
session->ReceivedMidi(buffer[j]);
session->EndReceivedMidi();

return consumed;
return parserReturn::Processed;
}

size_t decodeMidiSysEx(RtpBuffer_t &buffer)
parserReturn decodeMidiSysEx(RtpBuffer_t &buffer, size_t &consumed)
{
size_t consumed = 1; // beginning SysEx Token is not counted (as it could remain)
consumed = 1; // beginning SysEx Token is not counted (as it could remain)
size_t i = 0;
auto octet = buffer[++i];

Expand All @@ -237,9 +237,9 @@ size_t decodeMidiSysEx(RtpBuffer_t &buffer)
consumed++;
octet = buffer[i++];
if (octet == MIDI_NAMESPACE::MidiType::SystemExclusiveEnd) // Complete message
return consumed;
return parserReturn::Processed;
else if (octet == MIDI_NAMESPACE::MidiType::SystemExclusiveStart) // Start
return consumed;
return parserReturn::Processed;
}

// begin of the SysEx is found, not the end.
Expand All @@ -266,5 +266,7 @@ size_t decodeMidiSysEx(RtpBuffer_t &buffer)
midiCommandLength += 1; // adding the manual SysEx SystemExclusiveEnd

// indicates split SysEx
return buffer.max_size() + 1;
consumed = buffer.max_size() + 1;

return parserReturn::Processed;
}
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