VisionIpc: fix exception if server is killed while client is getting …

…streams (commaai#638)

* Update visionipc_client.cc

* and here in some cases

* lines

msgq/visionipc/visionipc_client.cc

@@ -54,6 +54,12 @@ bool VisionIpcClient::connect(bool blocking){
   int fds[VISIONIPC_MAX_FDS];
   VisionBuf bufs[VISIONIPC_MAX_FDS];
   r = ipc_sendrecv_with_fds(false, socket_fd, &bufs, sizeof(bufs), fds, VISIONIPC_MAX_FDS, &num_buffers);
+  if (r < 0) {
+    // only expected error is server shutting down
+    assert(errno == ECONNRESET);
+    close(socket_fd);
+    return false;
+  }
 
   assert(num_buffers >= 0);
   assert(r == sizeof(VisionBuf) * num_buffers);
@@ -122,7 +128,14 @@ std::set<VisionStreamType> VisionIpcClient::getAvailableStreams(const std::strin
 
   VisionStreamType available_streams[VISION_STREAM_MAX] = {};
   r = ipc_sendrecv_with_fds(false, socket_fd, &available_streams, sizeof(available_streams), nullptr, 0, nullptr);
-  assert((r >= 0) && (r % sizeof(VisionStreamType) == 0));
+  if (r < 0) {
+    // only expected error is server shutting down
+    assert(errno == ECONNRESET);
+    close(socket_fd);
+    return {};
+  }
+
+  assert(r % sizeof(VisionStreamType) == 0);
   close(socket_fd);
   return std::set<VisionStreamType>(available_streams, available_streams + r / sizeof(VisionStreamType));
 }