From cd6197caa33e9356e97518eaf54a5cfa592670da Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Matt=C3=A9o=20Delabre?= <spam@delab.re>
Date: Wed, 27 Jan 2021 12:42:01 +0100
Subject: [PATCH] Fight against zombies

---
 runall.py | 37 +++++++++++++++++++++----------------
 1 file changed, 21 insertions(+), 16 deletions(-)

diff --git a/runall.py b/runall.py
index 533cb7d..3348c54 100644
--- a/runall.py
+++ b/runall.py
@@ -1,26 +1,31 @@
 from itertools import product
-import subprocess
+import signal
+from subprocess import DEVNULL, PIPE, Popen, TimeoutExpired
 
 chars = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~ '
 
+# Prevent zombie processes
+signal.signal(signal.SIGCHLD, signal.SIG_IGN)
+
 
 def check_pair(script, instr, outstr):
+    process = Popen(
+        ["/usr/bin/env", "bash", "-c", "--", script],
+        stdin=PIPE,
+        stdout=PIPE,
+        stderr=DEVNULL,
+    )
+
     try:
-        result = subprocess.run(
-            [
-                "/usr/bin/env", "bash", "-c",
-                ";\n".join((
-                    # Cleanup child processes on exit
-                    "trap 'kill -9 $(jobs -p)' SIGINT SIGTERM EXIT",
-                    script,
-                ))
-            ],
-            timeout=5,
-            input=instr.encode(),
-            capture_output=True,
-        )
-        return result.returncode == 0 and result.stdout == outstr.encode()
-    except subprocess.TimeoutExpired:
+        stdout, stderr = process.communicate(instr.encode(), timeout=5)
+        return process.returncode == 0 and stdout == outstr.encode()
+    except TimeoutExpired:
+        try:
+            process.kill()
+            stdout, stderr = process.communicate()
+        except ProcessLookupError:
+            pass
+
         return False