Connection enters bad state

[floitsch]

With alpha.75, and http v2.1.
At some point my connection seems to have had an issue:

******************************************************************************
EXCEPTION error. 
DEADLINE_EXCEEDED
  0: __Monitor__.await         <sdk>/core/monitor_impl_.toit:28:20
  1: ResourceState_.wait_for_state_ <sdk>/core/events_.toit:55:5
  2: ResourceState_.wait_for_state.<block> <sdk>/core/events_.toit:19:12
  3: __Monitor__.locked_.<block> <sdk>/core/monitor_impl_.toit:123:12
  4: __Monitor__.locked_       <sdk>/core/monitor_impl_.toit:95:3
  5: ResourceState_.wait_for_state <sdk>/core/events_.toit:18:3
  6: TcpSocket_.ensure_state_  <sdk>/net/modules/tcp.toit:67:26
  7: TcpSocket.read            <sdk>/net/modules/tcp.toit:156:16
  8: BufferedReader.more_      <sdk>/reader.toit:82:22
  9: BufferedReader.ensure_    <sdk>/reader.toit:69:14
 10: BufferedReader.ensure     <sdk>/reader.toit:102:5
 11: BufferedReader.byte       <sdk>/reader.toit:179:5
 12: Session.extract_first_message_ <sdk>/tls/session.toit:456:17
...
 27: RequestOutgoing.send      <pkg:pkg-http>/request.toit:48:32
 28: Client.post_.<block>.<block> <pkg:pkg-http>/client.toit:463:28
 29: Client.try_to_reuse_.<block> <pkg:pkg-http>/client.toit:642:7
 30: catch.<block>             <sdk>/core/exceptions.toit:124:10
 31: catch                     <sdk>/core/exceptions.toit:122:1
 32: catch                     <sdk>/core/exceptions.toit:85:10
 33: Client.try_to_reuse_      <pkg:pkg-http>/client.toit:641:5
 34: Client.post_.<block>      <pkg:pkg-http>/client.toit:460:7
 35: SmallInteger_.repeat      <sdk>/core/numbers.toit:1194:3
 36: Client.post_              <pkg:pkg-http>/client.toit:458:19
 37: Client.post_json          <pkg:pkg-http>/client.toit:523:12

After that the program never recovered. From then on, a request always yielded the following error:

******************************************************************************
EXCEPTION error. 
Mbedtls high level error 0x7700 - see https://gist.github.com/erikcorry/b25bdcacf3e0086f8a2afb688420678e
  0: tls_error_                <sdk>/tls/session.toit:741:3
  1: Session.handshake_        <sdk>/tls/session.toit:267:9
  2: Session.handshake.<block> <sdk>/tls/session.toit:211:7
  3: Session.handshake         <sdk>/tls/session.toit:172:3
  4: Session.ensure_handshaken_ <sdk>/tls/session.toit:362:5
  5: Session.write             <sdk>/tls/session.toit:298:5
  6: Socket.write              <sdk>/tls/socket.toit:97:21
  7: Writer.write              <sdk>/writer.toit:39:23
  8: Connection.send_headers   <pkg:pkg-http>/connection.toit:119:13
  9: RequestOutgoing.send      <pkg:pkg-http>/request.toit:48:32
 10: Client.post_.<block>.<block> <pkg:pkg-http>/client.toit:463:28
 11: Client.try_to_reuse_.<block> <pkg:pkg-http>/client.toit:642:7
 12: catch.<block>             <sdk>/core/exceptions.toit:124:10
 13: catch                     <sdk>/core/exceptions.toit:122:1
 14: catch                     <sdk>/core/exceptions.toit:85:10
 15: Client.try_to_reuse_      <pkg:pkg-http>/client.toit:641:5
 16: Client.post_.<block>      <pkg:pkg-http>/client.toit:460:7
 17: SmallInteger_.repeat      <sdk>/core/numbers.toit:1194:3
 18: Client.post_              <pkg:pkg-http>/client.toit:458:19
 19: Client.post_json          <pkg:pkg-http>/client.toit:523:12
...
******************************************************************************

[kasperl]

This smells like we forget to close the client on the DEADLINE_EXCEEDED error, @erikcorry.

[kasperl]

It looks like we get the timeout as part of a TLS handshake that is part of sending the first headers. Then we do not close the connection and try to redo the handshake on next request.