DEVELOPMENT.md

Debugging test

MacOS

You could debug tests with Delve debugger. Run:

make test-mac-debug

This command will run build gvisor binary with debugger enabled.

Note: By default it would use --continue dlv option to not pause gvisor execution on start, if debugger is not connected. To pause gvisor execution until debugger is connected just remove "--continue" parameter from this line

And debug server with 2345 port, you could use any delve client to interact with debugger

GoLand Example

Create new Go Remote debug configuration:

1. Click Edit | Run Configurations. Alternatively, click the list of run/debug configurations on the toolbar and select Edit Configurations.
2. In the Run/Debug Configurations dialog, click the Add button (the Add button) and select Go Remote.
3. Set meaningful name
4. In the Host field, keep localhost
5. In the Port field, keep 2345 port number
6. Click OK button

Run gvisor tests with debug with:

make test-mac-debug

wait until Listening for remote connections (connections are not authenticated nor encrypted) message it appears. Click on debug button on Golang, ensure that your Go Remote profile is selected.

Have fun with debugging.

VSCode

Create/edit launch.json by adding this configuration:

   {
      "name": "Connect to Gvisor",
      "type": "go",
      "request": "attach",
      "mode": "remote",
      "remotePath": "${workspaceFolder}",
      "port": 2345,
      "host": "localhost"
    }

Run gvisor tests with debug with:

make test-mac-debug

wait until Listening for remote connections (connections are not authenticated nor encrypted) message it appears. Execute the launch attach request(Connect to Gvisor).

Have fun with debugging.

CLI Example

Connect to debugger server with:

dlv connect :2345

Example of usage:

Type 'help' for list of commands.
(dlv) break main.main
Breakpoint 1 set at 0xe735776 for main.main() ./work/redhat/gvisor-tap-vsock/cmd/gvproxy/main.go:59
(dlv) continue
> [Breakpoint 1] main.main() ./work/redhat/gvisor-tap-vsock/cmd/gvproxy/main.go:59 (hits goroutine(1):1 total:1) (PC: 0xe735776)
    54:         hostIP      = "192.168.127.254"
    55:         host        = "host"
    56:         gateway     = "gateway"
    57: )
    58:
=>  59: func main() {
    60:         version := types.NewVersion("gvproxy")
    61:         version.AddFlag()
    62:         flag.Var(&endpoints, "listen", "control endpoint")
    63:         flag.BoolVar(&debug, "debug", false, "Print debug info")
    64:         flag.IntVar(&mtu, "mtu", 1500, "Set the MTU")

More info about CLI client here

Editor integration

For available editor integration look there