Files

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1.8 KiB
Python

"""Private launch barrier for sdk.run_process; stdlib-only under Python -I."""
import json
import os
from pathlib import Path
import signal
import subprocess
import sys
import threading
import time
def watch_parent(expected: int):
while True:
if os.getppid() != expected:
os.killpg(os.getpid(), signal.SIGKILL)
time.sleep(0.1)
def main():
status = Path(sys.argv[1])
if os.name != "nt":
threading.Thread(target=watch_parent, args=(int(sys.argv[2]),), daemon=True).start()
# Until the parent owns our job/session and sends this line, no business
# process can start. Buffering is local; tool stdin uses a separate pipe.
control = sys.stdin.buffer.readline(1024 * 1024 + 1)
if not control.endswith(b"\n") or len(control) > 1024 * 1024:
return
request = json.loads(control)
size = request["input_size"]
if type(size) is not int or not 0 <= size <= 64 * 1024 * 1024:
return
content = sys.stdin.buffer.read(size) if request["has_input"] else None
if content is not None and len(content) != size:
return
try:
result = subprocess.run(
request["argv"],
shell=False,
stdin=None if request["has_input"] else subprocess.DEVNULL,
input=content,
creationflags=subprocess.CREATE_NO_WINDOW if os.name == "nt" else 0,
check=False,
)
response = {"returncode": result.returncode}
except OSError:
response = {"launch_failed": True}
pending = status.with_suffix(".tmp")
pending.write_text(json.dumps(response), encoding="utf-8")
pending.replace(status)
# Remain the session/group leader until the owner reclaims the whole tree.
while True:
time.sleep(60)
if __name__ == "__main__":
main()