[Lldb-commits] [lldb] [lldb-dap] Refactoring lldb-dap port listening mode to allow multiple connections. (PR #116392)

[Pavel Labath via lldb-commits]

================
@@ -1167,21 +1168,61 @@ def __init__(
 
             if log_file:
                 adaptor_env["LLDBDAP_LOG"] = log_file
+            args = [executable]
+
+            if connection is not None:
+                args.append("--connection")
+                args.append(connection)
+
             self.process = subprocess.Popen(
-                [executable],
+                args,
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 stderr=subprocess.PIPE,
                 env=adaptor_env,
             )
+
+        if connection is not None:
+            # If the process was also launched, parse the connection from the
+            # resolved connection. For example, if the connection
+            # `connection://localhost:0` was specified then the OS would pick a
+            # random port for listening and lldb-dap would print the listening
+            # port to stdout.
+            if self.process is not None:
+                # lldb-dap will print the listening address once the listener is
+                # made to stdout. The listener is formatted like
+                # `connection://host:port` or `unix-connection:///path`.
+                expected_prefix = "Listening for: "
+                out = self.process.stdout.readline().decode()
+                if not out.startswith(expected_prefix):
+                    self.process.kill()
+                    raise ValueError(
+                        "lldb-dap failed to print listening address, expected '{}', got '{}'".format(
+                            expected_prefix, out
+                        )
+                    )
+
+                # If the listener expanded into multiple addresses, use the first.
+                connection = (
+                    out.removeprefix(expected_prefix).rstrip("\r\n").split(",", 1)[0]
+                )
+
+            if connection.startswith("unix-connect://"):  # unix-connect:///path
----------------
labath wrote:

How about something like:
```suggestion
            scheme, address = connection.split("://")
            if connection == "unix-connect":  # unix-connect:///path
              # etc.
```

https://github.com/llvm/llvm-project/pull/116392