Make mkosi the foreground process again when child process finishes

We currently get "Job mkosi has stopped" when fetching running the
summary verb. Let's fix this by making sure we make mkosi the foreground
process again when we finish running a child process.

diff --git a/mkosi/run.py b/mkosi/run.py
index c6db1515e0ea260167f27a637a071148e21dc354..e3f46b46498a8f0eee4442ffeb8d9beb5e4e65c2 100644 (file)
--- a/mkosi/run.py
+++ b/mkosi/run.py
@@ -124,14 +124,15 @@ def become_root() -> tuple[int, int]:
     return SUBRANGE - 100, SUBRANGE - 100
 
 
-def foreground() -> None:
+def foreground(*, new_process_group: bool = True) -> None:
     """
     If we're connected to a terminal, put the process in a new process group and make that the foreground
     process group so that only this process receives SIGINT.
     """
     STDERR_FILENO = 2
     if os.isatty(STDERR_FILENO):
-        os.setpgrp()
+        if new_process_group:
+            os.setpgrp()
         old = signal.signal(signal.SIGTTOU, signal.SIG_IGN)
         os.tcsetpgrp(STDERR_FILENO, os.getpgrp())
         signal.signal(signal.SIGTTOU, old)
@@ -184,7 +185,11 @@ def fork_and_wait(target: Callable[[], T]) -> T:
 
         os._exit(0)
 
-    os.waitpid(pid, 0)
+    try:
+        os.waitpid(pid, 0)
+    finally:
+        foreground(new_process_group=False)
+
     result = pout.recv()
     if isinstance(result, RemoteException):
         # Reraise the original exception and attach the remote exception with full traceback as the cause.
@@ -242,6 +247,8 @@ def run(
         if log:
             logging.error(f'"{shlex.join(str(s) for s in cmdline)}" returned non-zero exit code {e.returncode}.')
         raise e
+    finally:
+        foreground(new_process_group=False)
 
 
 def spawn(