From 85537511dd188f54331abfaeeef7d7b950bf33bd Mon Sep 17 00:00:00 2001
From: Nick Phillips <nick.phillips@otago.ac.nz>
Date: Thu, 26 May 2016 17:25:54 +1200
Subject: [PATCH] Add debugging, stop hang in ProcessInThread.

---
 mdk/commands/behat.py |  4 ++++
 mdk/tools.py          | 24 +++++++++++++++---------
 2 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/mdk/commands/behat.py b/mdk/commands/behat.py
index f8a87a83..65258623 100644
--- a/mdk/commands/behat.py
+++ b/mdk/commands/behat.py
@@ -322,9 +322,13 @@ def run(self, args):
 
                 # Kill the remaining processes
                 if phpServer and phpServer.is_alive():
+                    logging.debug('Killing phpServer...')
                     phpServer.kill()
+                    logging.debug('phpServer killed.')
                 if seleniumServer and seleniumServer.is_alive():
+                    logging.debug('Killing seleniumServer...')
                     seleniumServer.kill()
+                    logging.debug('seleniumServer killed.')
 
                 # Disable Behat
                 if args.disable:
diff --git a/mdk/tools.py b/mdk/tools.py
index 6e75ce55..dad3e1bd 100644
--- a/mdk/tools.py
+++ b/mdk/tools.py
@@ -33,6 +33,7 @@
 import logging
 import hashlib
 import tempfile
+import errno
 from .config import Conf
 
 C = Conf()
@@ -177,11 +178,14 @@ def process(cmd, cwd=None, stdout=subprocess.PIPE, stderr=subprocess.PIPE):
     logging.debug(' '.join(cmd))
     try:
         proc = subprocess.Popen(cmd, cwd=cwd, stdout=stdout, stderr=stderr, encoding='utf-8')
+        logging.debug("subprocess started")
         (out, err) = proc.communicate()
+        logging.debug("communicate done")
     except KeyboardInterrupt as e:
         proc.kill()
         raise e
-    return (proc.returncode, out.decode('utf-8') if type(out) == bytes else out, err)
+    logging.debug("process returning")
+    return (proc.returncode, out.decode('utf-8') if type(out) -- bytes else out, err)
 
 
 def resolveEditor():
@@ -244,16 +248,18 @@ def __init__(self, cmd, cwd=None, stdout=subprocess.PIPE, stderr=subprocess.PIPE
         self.stderr = stderr
 
     def kill(self):
-        os.kill(self._pid, signal.SIGKILL)
+        try:
+            os.kill(self._pid, signal.SIGKILL)
+        except OSError as e:
+            if e.errno == errno.ESRCH:
+                logging.debug("ProcessInThread subprocess died before we could kill it")
 
     def run(self):
         logging.debug(' '.join(self.cmd))
         proc = subprocess.Popen(self.cmd, cwd=self.cwd, stdout=self.stdout, stderr=self.stderr)
         self._pid = proc.pid
-        while True:
-            if proc.poll():
-                break
-
-            # Reading the output seems to prevent the process to hang.
-            if self.stdout == subprocess.PIPE:
-                proc.stdout.read(1)
+        logging.debug("ProcessInThread subprocess started, pid %s", self._pid)
+        (out, err) = proc.communicate()
+        if err:
+            logging.debug(err)
+        logging.debug("ProcessInThread subprocess terminated with returncode %s", proc.returncode)