add expected_runtime_seconds and shutdown processes w/ grace period that run too long.

ra_aid/proc/interactive.py

@@ -19,6 +19,8 @@ import subprocess
 import select
 import termios
 import tty
+import time
+import signal
 from typing import List, Tuple
 
 import pyte
@@ -28,7 +30,7 @@ def render_line(line, columns: int) -> str:
     """Render a single screen line from the pyte buffer (a mapping of column to Char)."""
     return "".join(line[x].data for x in range(columns))
 
-def run_interactive_command(cmd: List[str]) -> Tuple[bytes, int]:
+def run_interactive_command(cmd: List[str], expected_runtime_seconds: int = 30) -> Tuple[bytes, int]:
     """
     Runs an interactive command with a pseudo-tty, capturing final scrollback history.
     
@@ -37,6 +39,12 @@ def run_interactive_command(cmd: List[str]) -> Tuple[bytes, int]:
       - `cmd` is a non-empty list where cmd[0] is the executable.
       - The executable is on PATH.
       
+    Args:
+      cmd: A list containing the command and its arguments.
+      expected_runtime_seconds: Expected runtime in seconds, defaults to 30.
+        If process exceeds 2x this value, it will be terminated gracefully.
+        If process exceeds 3x this value, it will be killed forcefully.
+      
     Returns:
       A tuple of (captured_output, return_code), where captured_output is a UTF-8 encoded
       bytes object containing the trimmed non-empty history lines from the terminal session.
@@ -93,11 +101,26 @@ def run_interactive_command(cmd: List[str]) -> Tuple[bytes, int]:
         stderr=slave_fd,
         bufsize=0,
         close_fds=True,
-        env=env
+        env=env,
+        preexec_fn=os.setsid  # Create new process group for proper signal handling
     )
     os.close(slave_fd)  # Close slave end in the parent process.
 
     captured_data = []
+    start_time = time.time()
+    was_terminated = False
+
+    def check_timeout():
+        elapsed = time.time() - start_time
+        if elapsed > 3 * expected_runtime_seconds:
+            # Force kill after 3x expected runtime
+            os.killpg(os.getpgid(proc.pid), signal.SIGKILL)
+            return True
+        elif elapsed > 2 * expected_runtime_seconds:
+            # Graceful termination after 2x expected runtime
+            os.killpg(os.getpgid(proc.pid), signal.SIGTERM)
+            return True
+        return False
 
     # If we're in an interactive TTY, set raw mode and forward input.
     if stdin_fd is not None and sys.stdin.isatty():
@@ -105,7 +128,10 @@ def run_interactive_command(cmd: List[str]) -> Tuple[bytes, int]:
         tty.setraw(stdin_fd)
         try:
             while True:
-                rlist, _, _ = select.select([master_fd, stdin_fd], [], [])
+                if check_timeout():
+                    was_terminated = True
+                    break
+                rlist, _, _ = select.select([master_fd, stdin_fd], [], [], 1.0)  # 1 second timeout for select
                 if master_fd in rlist:
                     try:
                         data = os.read(master_fd, 1024)
@@ -137,7 +163,13 @@ def run_interactive_command(cmd: List[str]) -> Tuple[bytes, int]:
         # Non-interactive mode (e.g., during unit tests).
         try:
             while True:
+                if check_timeout():
+                    was_terminated = True
+                    break
                 try:
+                    rlist, _, _ = select.select([master_fd], [], [], 1.0)  # 1 second timeout for select
+                    if not rlist:
+                        continue
                     data = os.read(master_fd, 1024)
                 except OSError as e:
                     if e.errno == errno.EIO:
@@ -165,6 +197,11 @@ def run_interactive_command(cmd: List[str]) -> Tuple[bytes, int]:
     trimmed_lines = [line for line in all_lines if line.strip()]
     final_output = "\n".join(trimmed_lines)
     
+    # Add timeout message if process was terminated
+    if was_terminated:
+        timeout_msg = f"\n[Process exceeded timeout ({expected_runtime_seconds} seconds expected)]"
+        final_output += timeout_msg
+    
     # Limit output to last 8000 bytes
     final_output = final_output[-8000:]