Noescape workaround

gap_nrf51.go

@@ -4,6 +4,11 @@ package bluetooth
 
 /*
 #include "ble_gap.h"
+
+// Workaround wrapper function to avoid pointer arguments escaping to heap
+static inline uint32_t sd_ble_gap_adv_start_noescape(ble_gap_adv_params_t const p_adv_params) {
+ return sd_ble_gap_adv_start(&p_adv_params);
+}
 */
 import "C"
 
@@ -75,5 +80,5 @@ func (a *Advertisement) start() uint32 {
  interval: uint16(a.interval),
  timeout: 0, // no timeout
  }
- return C.sd_ble_gap_adv_start(&params)
+ return C.sd_ble_gap_adv_start_noescape(params)
 }

gatts_sd.go

@@ -5,6 +5,16 @@ package bluetooth
 /*
 #include "ble_gap.h"
 #include "ble_gatts.h"
+
+// Workaround wrapper functions which prevent pointer arguments escaping to heap
+static inline uint32_t sd_ble_gatts_hvx_noescape(uint16_t conn_handle, uint16_t handle, uint8_t type, uint16_t offset, uint16_t len, uint8_t *p_data) {
+ ble_gatts_hvx_params_t p_hvx_params = {handle, type, offset, &len, p_data};
+ return sd_ble_gatts_hvx(conn_handle, &p_hvx_params);
+}
+
+static inline uint32_t sd_ble_gatts_value_set_noescape(uint16_t conn_handle, uint16_t handle, ble_gatts_value_t p_value) {
+ return sd_ble_gatts_value_set(conn_handle, handle, &p_value);
+}
 */
 import "C"
 
@@ -110,12 +120,13 @@ func (c *Characteristic) Write(p []byte) (n int, err error) {
  if connHandle != C.BLE_CONN_HANDLE_INVALID {
  // There is a connected central.
  p_len := uint16(len(p))
- errCode := C.sd_ble_gatts_hvx(connHandle, &C.ble_gatts_hvx_params_t{
- handle: c.handle,
- _type: C.BLE_GATT_HVX_NOTIFICATION,
- p_len: &p_len,
- p_data: &p[0],
- })
+ errCode := C.sd_ble_gatts_hvx_noescape(connHandle,
+ c.handle,
+ C.BLE_GATT_HVX_NOTIFICATION,
+ 0,
+ p_len,
+ &p[0],
+ )
 
  // Check for some expected errors. Don't report them as errors, but
  // instead fall through and do a normal characteristic value update.
@@ -133,7 +144,7 @@ func (c *Characteristic) Write(p []byte) (n int, err error) {
  }
  }
 
- errCode := C.sd_ble_gatts_value_set(C.BLE_CONN_HANDLE_INVALID, c.handle, &C.ble_gatts_value_t{
+ errCode := C.sd_ble_gatts_value_set_noescape(C.BLE_CONN_HANDLE_INVALID, c.handle, C.ble_gatts_value_t{
  len: uint16(len(p)),
  p_value: &p[0],
  })