From 32e25cbca210a359b09768537b6f443fe90a3070 Mon Sep 17 00:00:00 2001 From: Romain Forlot Date: Tue, 20 Jun 2017 10:24:05 +0000 Subject: Separation Generator to a dedicated repo Change-Id: Id94831651c3266861435272a6e36c7884bef2c45 Signed-off-by: Romain Forlot --- CAN-binder/libs/isotp-c/src/isotp/isotp.c | 32 ----- CAN-binder/libs/isotp-c/src/isotp/isotp.h | 41 ------ CAN-binder/libs/isotp-c/src/isotp/isotp_types.h | 144 -------------------- CAN-binder/libs/isotp-c/src/isotp/receive.c | 166 ------------------------ CAN-binder/libs/isotp-c/src/isotp/receive.h | 86 ------------ CAN-binder/libs/isotp-c/src/isotp/send.c | 89 ------------- CAN-binder/libs/isotp-c/src/isotp/send.h | 86 ------------ 7 files changed, 644 deletions(-) delete mode 100644 CAN-binder/libs/isotp-c/src/isotp/isotp.c delete mode 100644 CAN-binder/libs/isotp-c/src/isotp/isotp.h delete mode 100644 CAN-binder/libs/isotp-c/src/isotp/isotp_types.h delete mode 100644 CAN-binder/libs/isotp-c/src/isotp/receive.c delete mode 100644 CAN-binder/libs/isotp-c/src/isotp/receive.h delete mode 100644 CAN-binder/libs/isotp-c/src/isotp/send.c delete mode 100644 CAN-binder/libs/isotp-c/src/isotp/send.h (limited to 'CAN-binder/libs/isotp-c/src') diff --git a/CAN-binder/libs/isotp-c/src/isotp/isotp.c b/CAN-binder/libs/isotp-c/src/isotp/isotp.c deleted file mode 100644 index ce87f1b..0000000 --- a/CAN-binder/libs/isotp-c/src/isotp/isotp.c +++ /dev/null @@ -1,32 +0,0 @@ -#include -#include -#include - -/* void isotp_set_timeout(IsoTpHandler* handler, uint16_t timeout_ms) { */ - /* handler->timeout_ms = timeout_ms; */ -/* } */ - -IsoTpShims isotp_init_shims(LogShim log, SendCanMessageShim send_can_message, - SetTimerShim set_timer) { - IsoTpShims shims = { - log: log, - send_can_message: send_can_message, - set_timer: set_timer, - frame_padding: ISO_TP_DEFAULT_FRAME_PADDING_STATUS - }; - return shims; -} - -void isotp_message_to_string(const IsoTpMessage* message, char* destination, - size_t destination_length) { - snprintf(destination, destination_length, "ID: 0x%" SCNd32 ", Payload: 0x%02x%02x%02x%02x%02x%02x%02x%02x", - message->arbitration_id, - message->payload[0], - message->payload[1], - message->payload[2], - message->payload[3], - message->payload[4], - message->payload[5], - message->payload[6], - message->payload[7]); -} diff --git a/CAN-binder/libs/isotp-c/src/isotp/isotp.h b/CAN-binder/libs/isotp-c/src/isotp/isotp.h deleted file mode 100644 index 3a3658c..0000000 --- a/CAN-binder/libs/isotp-c/src/isotp/isotp.h +++ /dev/null @@ -1,41 +0,0 @@ -#ifndef __ISOTP_H__ -#define __ISOTP_H__ - -#include -#include -#include -#include -#include -#include - -#ifdef __cplusplus -extern "C" { -#endif - -/* Public: Initialize an IsoTpShims with the given callback functions. - * - * If any callbacks are not to be used, set them to NULL. For documentation of - * the function type signatures, see isotp_types.h. This struct is a handy - * encapsulation used to pass the shims around to the various isotp_* functions. - * - * Returns a struct with the fields initailized to the callbacks. - */ -IsoTpShims isotp_init_shims(LogShim log, - SendCanMessageShim send_can_message, - SetTimerShim set_timer); - -/* Public: Render an IsoTpMessage as a string into the given buffer. - * - * message - the message to convert to a string, for debug logging. - * destination - the target string buffer. - * destination_length - the size of the destination buffer, i.e. the max size - * for the rendered string. - */ -void isotp_message_to_string(const IsoTpMessage* message, char* destination, - size_t destination_length); - -#ifdef __cplusplus -} -#endif - -#endif // __ISOTP_H__ diff --git a/CAN-binder/libs/isotp-c/src/isotp/isotp_types.h b/CAN-binder/libs/isotp-c/src/isotp/isotp_types.h deleted file mode 100644 index 3b7fd26..0000000 --- a/CAN-binder/libs/isotp-c/src/isotp/isotp_types.h +++ /dev/null @@ -1,144 +0,0 @@ -#ifndef __ISOTP_TYPES__ -#define __ISOTP_TYPES__ - -#include -#include -#include - -#define CAN_MESSAGE_BYTE_SIZE 8 -#define MAX_ISO_TP_MESSAGE_SIZE 4096 -// TODO we want to avoid malloc, and we can't be allocated 4K on the stack for -// each IsoTpMessage, so for now we're setting an artificial max message size -// here - for most multi-frame use cases, 256 bytes is plenty. -#define OUR_MAX_ISO_TP_MESSAGE_SIZE 127 - -/* Private: IsoTp nibble specifics for PCI and Payload. - */ -#define PCI_NIBBLE_INDEX 0 -#define PAYLOAD_LENGTH_NIBBLE_INDEX 1 -#define PAYLOAD_BYTE_INDEX 1 - -/* Private: The default timeout to use when waiting for a response during a - * multi-frame send or receive. - */ -#define ISO_TP_DEFAULT_RESPONSE_TIMEOUT 100 - -/* Private: Determines if by default, padding is added to ISO-TP message frames. - */ -#define ISO_TP_DEFAULT_FRAME_PADDING_STATUS true - -#ifdef __cplusplus -extern "C" { -#endif - -/* Public: A container for a sent or received ISO-TP message. - * - * completed - An IsoTpMessage is the return value from a few functions - this - * attribute will be true if the message is actually completely received. - * If the function returns but is only partially through receiving the - * message, this will be false, the multi_frame attribute will be true, - * and you should not consider the other data to be valid. - * multi_frame - Designates the message is being built with multi-frame. - * arbitration_id - The arbitration ID of the message. - * payload - The optional payload of the message - don't forget to check the - * size! - * size - The size of the payload. The size will be 0 if there is no payload. - */ -typedef struct { - const uint32_t arbitration_id; - uint8_t payload[OUR_MAX_ISO_TP_MESSAGE_SIZE]; - uint16_t size; - bool completed; - bool multi_frame; -} IsoTpMessage; - -/* Public: The type signature for an optional logging function, if the user - * wishes to provide one. It should print, store or otherwise display the - * message. - * - * message - A format string to log using the given parameters. - * ... (vargs) - the parameters for the format string. - */ -typedef void (*LogShim)(const char* message, ...); -/* Public: The type signature for a function to send a single CAN message. - * - * arbitration_id - The arbitration ID of the message. - * data - The data payload for the message. NULL is valid if size is also 0. - * size - The size of the data payload, in bytes. - * - * Returns true if the CAN message was sent successfully. - */ -typedef bool (*SendCanMessageShim)(const uint32_t arbitration_id, - const uint8_t* data, const uint8_t size); - -/* Public: The type signature for a... TODO, not used yet. - */ -typedef bool (*SetTimerShim)(uint16_t time_ms, void (*callback)); - -/* Public: The signature for a function to be called when an ISO-TP message has - * been completely received. - * - * message - The received message. - */ -typedef void (*IsoTpMessageReceivedHandler)(const IsoTpMessage* message); - -/* Public: the signature for a function to be called when an ISO-TP message has - * been completely sent, or had a fatal error during sending. - * - * message - The sent message. - * success - True if the message was sent successfully. - */ -typedef void (*IsoTpMessageSentHandler)(const IsoTpMessage* message, - const bool success); - -/* Public: The signature for a function to be called when a CAN frame has been - * sent as as part of sending or receive an ISO-TP message. - * - * This is really only useful for debugging the library itself. - * - * message - The ISO-TP message that generated this CAN frame. - */ -typedef void (*IsoTpCanFrameSentHandler)(const IsoTpMessage* message); - -/* Public: A container for the 3 shim functions used by the library to interact - * with the wider system. - * - * Use the isotp_init_shims(...) function to create an instance of this struct. - * - * By default, all CAN frames sent from this device in the process of an ISO-TP - * message are padded out to a complete 8 byte frame. This is often required by - * ECUs. To disable this feature, change the 'frame_padding' field to false on - * the IsoTpShims object returned from isotp_init_shims(...). - * - * frame_padding - true if outgoing CAN frames should be padded to a full 8 - * bytes. - */ -typedef struct { - LogShim log; - SendCanMessageShim send_can_message; - SetTimerShim set_timer; - bool frame_padding; -} IsoTpShims; - -/* Private: PCI types, for identifying each frame of an ISO-TP message. - */ -typedef enum { - PCI_SINGLE = 0x0, - PCI_FIRST_FRAME = 0x1, - PCI_CONSECUTIVE_FRAME = 0x2, - PCI_FLOW_CONTROL_FRAME = 0x3 -} IsoTpProtocolControlInformation; - -/* Private: PCI flow control identifiers. - */ -typedef enum { - PCI_FLOW_STATUS_CONTINUE = 0x0, - PCI_FLOW_STATUS_WAIT = 0x1, - PCI_FLOW_STATUS_OVERFLOW = 0x2 -} IsoTpFlowStatus; - -#ifdef __cplusplus -} -#endif - -#endif // __ISOTP_TYPES__ diff --git a/CAN-binder/libs/isotp-c/src/isotp/receive.c b/CAN-binder/libs/isotp-c/src/isotp/receive.c deleted file mode 100644 index 35b7a2a..0000000 --- a/CAN-binder/libs/isotp-c/src/isotp/receive.c +++ /dev/null @@ -1,166 +0,0 @@ -#include -#include -#include -#include -#include - -#define ARBITRATION_ID_OFFSET 0x8 - -static void isotp_complete_receive(IsoTpReceiveHandle* handle, IsoTpMessage* message) { - if(handle->message_received_callback != NULL) { - handle->message_received_callback(message); - } -} - -bool isotp_handle_single_frame(IsoTpReceiveHandle* handle, IsoTpMessage* message) { - isotp_complete_receive(handle, message); - return true; -} - -bool isotp_handle_multi_frame(IsoTpReceiveHandle* handle, IsoTpMessage* message) { - // call this once all consecutive frames have been received - isotp_complete_receive(handle, message); - return true; -} - -bool isotp_send_flow_control_frame(IsoTpShims* shims, IsoTpMessage* message) { - uint8_t can_data[CAN_MESSAGE_BYTE_SIZE] = {0}; - - if(!set_nibble(PCI_NIBBLE_INDEX, PCI_FLOW_CONTROL_FRAME, can_data, sizeof(can_data))) { - shims->log("Unable to set PCI in CAN data"); - return false; - } - - shims->send_can_message(message->arbitration_id - ARBITRATION_ID_OFFSET, can_data, - shims->frame_padding ? 8 : 1 + message->size); - return true; -} - - -IsoTpReceiveHandle isotp_receive(IsoTpShims* shims, - const uint32_t arbitration_id, IsoTpMessageReceivedHandler callback) { - IsoTpReceiveHandle handle = { - success: false, - completed: false, - arbitration_id: arbitration_id, - message_received_callback: callback - }; - - return handle; -} - -IsoTpMessage isotp_continue_receive(IsoTpShims* shims, - IsoTpReceiveHandle* handle, const uint32_t arbitration_id, - const uint8_t data[], const uint8_t size) { - IsoTpMessage message = { - arbitration_id: arbitration_id, - completed: false, - multi_frame: false, - payload: {0}, - size: 0 - }; - - if(size < 1) { - return message; - } - - if(handle->arbitration_id != arbitration_id) { - if(shims->log != NULL) { - // You may turn this on for debugging, but in normal operation it's - // very noisy if you are passing all received CAN messages to this - // handler. - /* shims->log("The arb ID 0x%x doesn't match the expected rx ID 0x%x", */ - /* arbitration_id, handle->arbitration_id); */ - } - return message; - } - - IsoTpProtocolControlInformation pci = (IsoTpProtocolControlInformation) - get_nibble(data, size, 0); - - // TODO this is set up to handle rx a response with a payload, but not to - // handle flow control responses for multi frame messages that we're in the - // process of sending - - switch(pci) { - case PCI_SINGLE: { - uint8_t payload_length = get_nibble(data, size, 1); - - if(payload_length > 0) { - memcpy(message.payload, &data[1], payload_length); - } - - message.size = payload_length; - message.completed = true; - handle->success = true; - handle->completed = true; - isotp_handle_single_frame(handle, &message); - break; - } - //If multi-frame, then the payload length is contained in the 12 - //bits following the first nibble of Byte 0. - case PCI_FIRST_FRAME: { - uint16_t payload_length = (get_nibble(data, size, 1) << 8) + get_byte(data, size, 1); - - if(payload_length > OUR_MAX_ISO_TP_MESSAGE_SIZE) { - shims->log("Multi-frame response too large for receive buffer."); - break; - } - - //Need to allocate memory for the combination of multi-frame - //messages. That way we don't have to allocate 4k of memory - //for each multi-frame response. - uint8_t* combined_payload = NULL; - combined_payload = (uint8_t*)malloc(sizeof(uint8_t)*payload_length); - - if(combined_payload == NULL) { - shims->log("Unable to allocate memory for multi-frame response."); - break; - } - - memcpy(combined_payload, &data[2], CAN_MESSAGE_BYTE_SIZE - 2); - handle->receive_buffer = combined_payload; - handle->received_buffer_size = CAN_MESSAGE_BYTE_SIZE - 2; - handle->incoming_message_size = payload_length; - - message.multi_frame = true; - handle->success = false; - handle->completed = false; - isotp_send_flow_control_frame(shims, &message); - break; - } - case PCI_CONSECUTIVE_FRAME: { - uint8_t start_index = handle->received_buffer_size; - uint8_t remaining_bytes = handle->incoming_message_size - start_index; - message.multi_frame = true; - - if(remaining_bytes > 7) { - memcpy(&handle->receive_buffer[start_index], &data[1], CAN_MESSAGE_BYTE_SIZE - 1); - handle->received_buffer_size = start_index + 7; - } else { - memcpy(&handle->receive_buffer[start_index], &data[1], remaining_bytes); - handle->received_buffer_size = start_index + remaining_bytes; - - if(handle->received_buffer_size != handle->incoming_message_size){ - free(handle->receive_buffer); - handle->success = false; - shims->log("Error capturing all bytes of multi-frame. Freeing memory."); - } else { - memcpy(message.payload,&handle->receive_buffer[0],handle->incoming_message_size); - free(handle->receive_buffer); - message.size = handle->incoming_message_size; - message.completed = true; - shims->log("Successfully captured all of multi-frame. Freeing memory."); - - handle->success = true; - handle->completed = true; - isotp_handle_multi_frame(handle, &message); - } - } - break; - } - default: - break; - } - return message; -} diff --git a/CAN-binder/libs/isotp-c/src/isotp/receive.h b/CAN-binder/libs/isotp-c/src/isotp/receive.h deleted file mode 100644 index 6788914..0000000 --- a/CAN-binder/libs/isotp-c/src/isotp/receive.h +++ /dev/null @@ -1,86 +0,0 @@ -#ifndef __ISOTP_RECEIVE_H__ -#define __ISOTP_RECEIVE_H__ - -#include -#include -#include - -#ifdef __cplusplus -extern "C" { -#endif - -/* Public: A handle for beginning and continuing receiving a single ISO-TP - * message - both single and multi-frame. - * - * Since an ISO-TP message may contain multiple frames, we need to keep a handle - * around while waiting for subsequent CAN messages to complete the message. - * This struct encapsulates the local state required. - * - * completed - True if the received message request is completely finished. - * success - True if the message request was successful. The value if this field - * isn't valid if 'completed' isn't true. - */ -typedef struct { - bool completed; - bool success; - - // Private - uint32_t arbitration_id; - IsoTpMessageReceivedHandler message_received_callback; - uint16_t timeout_ms; - // timeout_ms: ISO_TP_DEFAULT_RESPONSE_TIMEOUT, - uint8_t* receive_buffer; - uint16_t received_buffer_size; - uint16_t incoming_message_size; - // TODO timer callback for multi frame -} IsoTpReceiveHandle; - -/* Public: Initiate receiving a single ISO-TP message on a particular - * arbitration ID. - * - * Note that no actual CAN data has been received at this point - this just sets - * up a handle to be used when new CAN messages to arrive, so they can be parsed - * as potential single or multi-frame ISO-TP messages. - * - * shims - Low-level shims required to send and receive CAN messages, etc. - * arbitration_id - The arbitration ID to receive the message on. - * callback - an optional function to be called when the message is completely - * received (use NULL if no callback required). - * - * Returns a handle to be used with isotp_continue_receive when a new CAN frame - * arrives. The 'completed' field in the returned IsoTpReceiveHandle will be true - * when the message is completely sent. - */ -IsoTpReceiveHandle isotp_receive(IsoTpShims* shims, - const uint32_t arbitration_id, IsoTpMessageReceivedHandler callback); - -/* Public: Continue to receive a an ISO-TP message, based on a freshly - * received CAN message. - * - * For a multi-frame ISO-TP message, this function must be called - * repeatedly whenever a new CAN message is received in order to complete - * receipt. - * - * TODO does this API work for if we wanted to receive an ISO-TP message and - * send our own flow control messages back? - * - * shims - Low-level shims required to send and receive CAN messages, etc. - * handle - An IsoTpReceiveHandle previously returned by isotp_receive(...). - * arbitration_id - The arbitration_id of the received CAN message. - * data - The data of the received CAN message. - * size - The size of the data in the received CAN message. - * - * Returns an IsoTpMessage with the 'completed' field set to true if a message - * was completely received. If 'completed' is false, more CAN frames are - * required to complete the messages, or the arbitration ID didn't match this - * handle. Keep passing the same handle to this function when CAN frames arrive. - */ -IsoTpMessage isotp_continue_receive(IsoTpShims* shims, - IsoTpReceiveHandle* handle, const uint32_t arbitration_id, - const uint8_t data[], const uint8_t size); - -#ifdef __cplusplus -} -#endif - -#endif // __ISOTP_RECEIVE_H__ diff --git a/CAN-binder/libs/isotp-c/src/isotp/send.c b/CAN-binder/libs/isotp-c/src/isotp/send.c deleted file mode 100644 index e849bb2..0000000 --- a/CAN-binder/libs/isotp-c/src/isotp/send.c +++ /dev/null @@ -1,89 +0,0 @@ -#include -#include -#include - -#define PCI_NIBBLE_INDEX 0 -#define PAYLOAD_LENGTH_NIBBLE_INDEX 1 -#define PAYLOAD_BYTE_INDEX 1 - -void isotp_complete_send(IsoTpShims* shims, IsoTpMessage* message, - bool status, IsoTpMessageSentHandler callback) { - if(callback != NULL) { - callback(message, status); - } -} - -IsoTpSendHandle isotp_send_single_frame(IsoTpShims* shims, IsoTpMessage* message, - IsoTpMessageSentHandler callback) { - IsoTpSendHandle handle = { - success: false, - completed: true - }; - - uint8_t can_data[CAN_MESSAGE_BYTE_SIZE] = {0}; - if(!set_nibble(PCI_NIBBLE_INDEX, PCI_SINGLE, can_data, sizeof(can_data))) { - shims->log("Unable to set PCI in CAN data"); - return handle; - } - - if(!set_nibble(PAYLOAD_LENGTH_NIBBLE_INDEX, message->size, can_data, - sizeof(can_data))) { - shims->log("Unable to set payload length in CAN data"); - return handle; - } - - if(message->size > 0) { - memcpy(&can_data[1], message->payload, message->size); - } - - shims->send_can_message(message->arbitration_id, can_data, - shims->frame_padding ? 8 : 1 + message->size); - handle.success = true; - isotp_complete_send(shims, message, true, callback); - return handle; -} - -IsoTpSendHandle isotp_send_multi_frame(IsoTpShims* shims, IsoTpMessage* message, - IsoTpMessageSentHandler callback) { - // TODO make sure to copy message into a local buffer - shims->log("Only single frame messages are supported"); - IsoTpSendHandle handle = { - success: false, - completed: true - }; - // TODO need to set sending and receiving arbitration IDs separately if we - // can't always just add 0x8 (and I think we can't) - return handle; -} - -IsoTpSendHandle isotp_send(IsoTpShims* shims, const uint16_t arbitration_id, - const uint8_t payload[], uint16_t size, - IsoTpMessageSentHandler callback) { - IsoTpMessage message = { - arbitration_id: arbitration_id, - size: size - }; - - memcpy(message.payload, payload, size); - if(size < 8) { - return isotp_send_single_frame(shims, &message, callback); - } else { - return isotp_send_multi_frame(shims, &message, callback); - } -} - -bool isotp_continue_send(IsoTpShims* shims, IsoTpSendHandle* handle, - const uint16_t arbitration_id, const uint8_t data[], - const uint8_t size) { - // TODO this will need to be tested when we add multi-frame support, - // which is when it'll be necessary to pass in CAN messages to SENDING - // handles. - if(handle->receiving_arbitration_id != arbitration_id) { - if(shims->log != NULL) { - shims->log("The arb ID 0x%x doesn't match the expected tx continuation ID 0x%x", - arbitration_id, handle->receiving_arbitration_id); - } - return false; - } - return false; -} diff --git a/CAN-binder/libs/isotp-c/src/isotp/send.h b/CAN-binder/libs/isotp-c/src/isotp/send.h deleted file mode 100644 index 1af3266..0000000 --- a/CAN-binder/libs/isotp-c/src/isotp/send.h +++ /dev/null @@ -1,86 +0,0 @@ -#ifndef __ISOTP_SEND_H__ -#define __ISOTP_SEND_H__ - -#include -#include -#include - -#ifdef __cplusplus -extern "C" { -#endif - -/* Public: A handle for beginning and continuing sending a single ISO-TP - * message - both single and multi-frame. - * - * Since an ISO-TP message may contain multiple frames, we need to keep a handle - * around while waiting for flow control messages from the receiver. - * This struct encapsulates the local state required. - * - * completed - True if the message was completely sent, or the send was - * otherwise cancelled. - * success - True if the message send request was successful. The value if this - * field isn't valid if 'completed' isn't true. - */ -typedef struct { - bool completed; - bool success; - - // Private - uint16_t sending_arbitration_id; - uint16_t receiving_arbitration_id; - IsoTpMessageSentHandler message_sent_callback; - IsoTpCanFrameSentHandler can_frame_sent_callback; - // TODO going to need some state here for multi frame messages -} IsoTpSendHandle; - -/* Public: Initiate sending a single ISO-TP message. - * - * If the message fits in a single ISO-TP frame (i.e. the payload isn't more - * than 7 bytes) it will be sent immediately and the returned IsoTpSendHandle's - * 'completed' flag will be true. - * - * For multi-frame messages, see isotp_continue_send(...). - * - * shims - Low-level shims required to send CAN messages, etc. - * arbitration_id - The arbitration ID to send the message on. - * payload - The payload for the message. If no payload, NULL is valid is size - * is also 0. - * size - The size of the payload, or 0 if no payload. - * callback - an optional function to be called when the message is completely - * sent (use NULL if no callback required). - * - * Returns a handle to be used with isotp_continue_send to continue sending - * multi-frame messages. The 'completed' field in the returned IsoTpSendHandle - * will be true when the message is completely sent. - */ -IsoTpSendHandle isotp_send(IsoTpShims* shims, const uint16_t arbitration_id, - const uint8_t payload[], uint16_t size, - IsoTpMessageSentHandler callback); - -/* Public: Continue to send a multi-frame ISO-TP message, based on a freshly - * received CAN message (potentially from the receiver about flow control). - * - * For a multi-frame ISO-TP message, this function must be called - * repeatedly whenever a new CAN message is received in order to complete the - * send. The sender can't just blast everything onto the bus at once - it must - * wait for some response from the receiver to know how much to send at once. - * - * shims - Low-level shims required to send CAN messages, etc. - * handle - An IsoTpSendHandle previously returned by isotp_send(...). - * arbitration_id - The arbitration_id of the received CAN message. - * data - The data of the received CAN message. - * size - The size of the data in the received CAN message. - * - * Returns true if the message was completely sent, or the send was - * otherwise cancelled. Check the 'success' field of the handle to see if - * it was successful. - */ -bool isotp_continue_send(IsoTpShims* shims, IsoTpSendHandle* handle, - const uint16_t arbitration_id, const uint8_t data[], - const uint8_t size); - -#ifdef __cplusplus -} -#endif - -#endif // __ISOTP_SEND_H__ -- cgit 1.2.3-korg