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Merge pull request #974 from fredizzimo/remove_malloc_from_sysex

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API Sysex fixes
This commit is contained in:
Jack Humbert 2016-12-30 11:05:50 -05:00 • committed by GitHub
commit 2eced29675
4 changed files with 71 additions and 27 deletions
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60
quantum/api/api_sysex.c
View file

@ -1,4 +1,6 @@
#include "api_sysex.h"
#include "sysex_tools.h"
#include "print.h"
void send_bytes_sysex(uint8_t message_type, uint8_t data_type, uint8_t * bytes, uint16_t length) {
// SEND_STRING("\nTX: ");
@ -6,24 +8,50 @@ void send_bytes_sysex(uint8_t message_type, uint8_t data_type, uint8_t * bytes,
// send_byte(bytes[i]);
// SEND_STRING(" ");
// }
uint8_t * precode = malloc(sizeof(uint8_t) * (length + 2));
precode[0] = message_type;
precode[1] = data_type;
memcpy(precode + 2, bytes, length);
uint8_t * encoded = malloc(sizeof(uint8_t) * (sysex_encoded_length(length + 2)));
uint16_t encoded_length = sysex_encode(encoded, precode, length + 2);
uint8_t * array = malloc(sizeof(uint8_t) * (encoded_length + 5));
array[0] = 0xF0;
array[1] = 0x00;
array[2] = 0x00;
array[3] = 0x00;
array[encoded_length + 4] = 0xF7;
memcpy(array + 4, encoded, encoded_length);
midi_send_array(&midi_device, encoded_length + 5, array);
if (length > API_SYSEX_MAX_SIZE) {
xprintf("Sysex msg too big %d %d %d", message_type, data_type, length);
return;
}
// The buffer size required is calculated as the following
// API_SYSEX_MAX_SIZE is the maximum length
// In addition to that we have a two byte message header consisting of the message_type and data_type
// This has to be encoded with an additional overhead of one byte for every starting 7 bytes
// We just add one extra byte in case it's not divisible by 7
// Then we have an unencoded header consisting of 4 bytes
// Plus a one byte terminator
const unsigned message_header = 2;
const unsigned unencoded_message = API_SYSEX_MAX_SIZE + message_header;
const unsigned encoding_overhead = unencoded_message / 7 + 1;
const unsigned encoded_size = unencoded_message + encoding_overhead;
const unsigned unencoded_header = 4;
const unsigned terminator = 1;
const unsigned buffer_size = encoded_size + unencoded_header + terminator;
uint8_t buffer[encoded_size + unencoded_header + terminator];
// The unencoded header
buffer[0] = 0xF0;
buffer[1] = 0x00;
buffer[2] = 0x00;
buffer[3] = 0x00;
// We copy the message to the end of the array, this way we can do an inplace encoding, using the same
// buffer for both input and output
const unsigned message_size = length + message_header;
uint8_t* unencoded_start = buffer + buffer_size - message_size;
uint8_t* ptr = unencoded_start;
*(ptr++) = message_type;
*(ptr++) = data_type;
memcpy(ptr, bytes, length);
unsigned encoded_length = sysex_encode(buffer + unencoded_header, unencoded_start, message_size);
unsigned final_size = unencoded_header + encoded_length + terminator;
buffer[final_size - 1] = 0xF7;
midi_send_array(&midi_device, final_size, buffer);
// SEND_STRING("\nTD: ");
// for (uint8_t i = 0; i < encoded_length + 5; i++) {
// send_byte(array[i]);
// send_byte(buffer[i]);
// SEND_STRING(" ");
// }
}
}

2
quantum/config_common.h
View file

@ -80,4 +80,6 @@
# endif
#endif
#define API_SYSEX_MAX_SIZE 32
#endif