Fix Peak ISO-TP instability during large UDS transfers (#425)

src/main/docan/peak/helpers.ts

@@ -0,0 +1,119 @@
+export const PEAK_WRITE_RETRY_MAX = 100
+export const PEAK_WRITE_RETRY_DELAY_MS = 1
+
+export function delayMs(ms: number) {
+  const end = process.hrtime.bigint() + BigInt(ms * 1_000_000)
+  while (process.hrtime.bigint() < end) {
+    // busy wait for short native write retries
+  }
+}
+
+export type PeakStatusConstants = {
+  PCANTP_STATUS_QUEUE_TX_FULL: number
+  PCANTP_STATUS_LOCK_TIMEOUT: number
+  PCANTP_STATUS_NO_MESSAGE: number
+}
+
+export type PeakMsgFlagConstants = {
+  PCANTP_MSGFLAG_LOOPBACK: number
+}
+
+export type PeakNetStatusConstants = {
+  PCANTP_NETSTATUS_OK: number
+  PCANTP_NETSTATUS_TIMEOUT_A: number
+  PCANTP_NETSTATUS_TIMEOUT_Bs: number
+  PCANTP_NETSTATUS_TIMEOUT_Cr: number
+  PCANTP_NETSTATUS_WRONG_SN: number
+  PCANTP_NETSTATUS_INVALID_FS: number
+  PCANTP_NETSTATUS_BUFFER_OVFLW: number
+}
+
+export function isTransientPeakWriteStatus(status: number, peak: PeakStatusConstants): boolean {
+  return status == peak.PCANTP_STATUS_QUEUE_TX_FULL || status == peak.PCANTP_STATUS_LOCK_TIMEOUT
+}
+
+export function isPeakReadEmpty(status: number, peak: PeakStatusConstants): boolean {
+  return status == peak.PCANTP_STATUS_NO_MESSAGE
+}
+
+/** Peak may OR LOOPBACK with ISOTP_FRAME / QOVERRUN bits — never compare with ==. */
+export function isPeakLoopback(flags: number, peak: PeakMsgFlagConstants): boolean {
+  return (flags & peak.PCANTP_MSGFLAG_LOOPBACK) != 0
+}
+
+/**
+ * Multi-frame TX: Peak delivers an INDICATION_TX first, then a final confirmation without the
+ * indication flag (see PCANTP_PARAMETER_MSG_PENDING). Only resolve when there is no TX indication,
+ * or GetMsgProgress reports COMPLETED on the indication.
+ */
+export function shouldResolveTpWriteOnLoopback(
+  hasIndicationTx: boolean,
+  progressCompleted: boolean
+): boolean {
+  if (hasIndicationTx) {
+    return progressCompleted
+  }
+  return true
+}
+
+/**
+ * Per Peak docs, the complete ISO-TP RX payload is the message WITHOUT INDICATION_RX.
+ * Pending indication messages must not be emitted as finished reads.
+ */
+export function shouldEmitTpRead(hasIndicationRx: boolean): boolean {
+  return !hasIndicationRx
+}
+
+export type PeakTpNetError =
+  | 'TP_TIMEOUT_A'
+  | 'TP_TIMEOUT_BS'
+  | 'TP_TIMEOUT_CR'
+  | 'TP_WRONG_SN'
+  | 'TP_INVALID_FS'
+  | 'TP_BUFFER_OVERFLOW'
+  | 'TP_BUS_ERROR'
+  | null
+
+export function mapPeakNetStatusToTpError(
+  netstatus: number,
+  peak: PeakNetStatusConstants
+): PeakTpNetError {
+  if (netstatus == peak.PCANTP_NETSTATUS_OK) {
+    return null
+  }
+  if (netstatus == peak.PCANTP_NETSTATUS_TIMEOUT_A) {
+    return 'TP_TIMEOUT_A'
+  }
+  if (netstatus == peak.PCANTP_NETSTATUS_TIMEOUT_Bs) {
+    return 'TP_TIMEOUT_BS'
+  }
+  if (netstatus == peak.PCANTP_NETSTATUS_TIMEOUT_Cr) {
+    return 'TP_TIMEOUT_CR'
+  }
+  if (netstatus == peak.PCANTP_NETSTATUS_WRONG_SN) {
+    return 'TP_WRONG_SN'
+  }
+  if (netstatus == peak.PCANTP_NETSTATUS_INVALID_FS) {
+    return 'TP_INVALID_FS'
+  }
+  if (netstatus == peak.PCANTP_NETSTATUS_BUFFER_OVFLW) {
+    return 'TP_BUFFER_OVERFLOW'
+  }
+  return 'TP_BUS_ERROR'
+}
+
+export function writePeakMessageWithRetry(
+  write: () => number,
+  peak: PeakStatusConstants,
+  maxRetries = PEAK_WRITE_RETRY_MAX,
+  delay = PEAK_WRITE_RETRY_DELAY_MS
+): number {
+  let res = write()
+  let attempt = 0
+  while (isTransientPeakWriteStatus(res, peak) && attempt < maxRetries) {
+    delayMs(delay)
+    res = write()
+    attempt++
+  }
+  return res
+}