Error while running examples/server.go

[wujiang]

• Platform

  Darwin Neptune 14.1.0 Darwin Kernel Version 14.1.0: Mon Dec 22 23:10:38 PST 2014

• Repro
  • run server.go: go run examples/server.go
  • select the peripheral on LightBlue

• stack trace

  ~GOPATH/src/github.com/paypal/gatt $ go run examples/server.go
  State: PoweredOn
  panic: runtime error: invalid memory address or nil pointer dereference
  [signal 0xb code=0x1 addr=0x30 pc=0x405828f]
  
  goroutine 17 [running, locked to thread]:
  github.com/paypal/gatt.(*central).stopNotify(0x0, 0xc208030180)
    /Users/wjiang/workspace/go/src/github.com/paypal/gatt/central_darwin.go:64 +0x1f
  github.com/paypal/gatt.(*device).respondToRequest(0xc20805a000, 0x16, 0xc20803a9c0)
    /Users/wjiang/workspace/go/src/github.com/paypal/gatt/device_darwin.go:312 +0x23a6
  github.com/paypal/gatt.(*device).HandleXpcEvent(0xc20805a000, 0xc20803a990, 0x0, 0x0)
    /Users/wjiang/workspace/go/src/github.com/paypal/gatt/device_darwin.go:348 +0x489
  github.com/paypal/gatt/xpc.handleXpcEvent(0x7200140, 0x4304e10)
    /Users/wjiang/workspace/go/src/github.com/paypal/gatt/xpc/xpc_darwin.go:199 +0x28b
  
  goroutine 1 [select (no cases)]:
  main.main()
    /Users/wjiang/workspace/go/src/github.com/paypal/gatt/examples/server.go:51 +0x24e
  
  goroutine 5 [chan receive]:
  github.com/paypal/gatt.(*device).loop(0xc20805a000)
    /Users/wjiang/workspace/go/src/github.com/paypal/gatt/device_darwin.go:448 +0x83
  created by github.com/paypal/gatt.(*device).Init
    /Users/wjiang/workspace/go/src/github.com/paypal/gatt/device_darwin.go:54 +0x58
  
  goroutine 18 [syscall, locked to thread]:
  runtime.goexit()
    /usr/local/Cellar/go/1.4/libexec/src/runtime/asm_amd64.s:2232 +0x1
  exit status 2

Please let me know if you need more information. Thank you.

[roylee17]

@wujiang Thanks for reporting, could you help to confirm the fix works for you as well?

[wujiang]

@roylee17, thank you for responding so fast.

The original problem is gone. But when I used LightBlue to interrogate it, I got this error:

It looks like the d.subscribers in line https://github.com/paypal/gatt/blob/a1218a6773043bc92bb2581a9686e03ac373017f/device_darwin.go#L311 is an empty map. Not sure if this is an issue.

[roylee17]

haven't seen it for a long time. I'm closing this issue now, but feel free to reopen it if any one see this again.