Avoid deadlock when calling subprocess.Popen(), ignore terminated bor…

…g processes when finding mount points. Fixes borgbase#187

src/vorta/borg/borg_thread.py

@@ -143,7 +143,7 @@ def run(self):
         logger.info('Running command %s', ' '.join(self.cmd))
 
         p = Popen(self.cmd, stdout=PIPE, stderr=PIPE, bufsize=1, universal_newlines=True,
-                  env=self.env, cwd=self.cwd, preexec_fn=os.setsid)
+                  env=self.env, cwd=self.cwd, start_new_session=True)
         self.process = p
 
         # Prevent blocking of stdout/err. Via https://stackoverflow.com/a/7730201/3983708

src/vorta/utils.py

@@ -268,22 +268,23 @@ def get_mount_points(repo_url):
     for proc in psutil.process_iter():
         try:
             name = proc.name()
-        except Exception:
-            # Getting the process name may fail (e.g. zombie process on macOS)
-            continue
-        if name == 'borg' or name.startswith('python'):
-            if 'mount' not in proc.cmdline():
-                continue
-
-            for idx, parameter in enumerate(proc.cmdline()):
-                if parameter.startswith(repo_url + '::'):
-                    archive_name = parameter[len(repo_url) + 2:]
+            if name == 'borg' or name.startswith('python'):
+                if 'mount' not in proc.cmdline():
+                    continue
 
-                    # The borg mount command specifies that the mount_point
-                    # parameter comes after the archive name
-                    if len(proc.cmdline()) > idx + 1:
-                        mount_point = proc.cmdline()[idx + 1]
-                        mount_points[archive_name] = mount_point
-                    break
+                for idx, parameter in enumerate(proc.cmdline()):
+                    if parameter.startswith(repo_url + '::'):
+                        archive_name = parameter[len(repo_url) + 2:]
+
+                        # The borg mount command specifies that the mount_point
+                        # parameter comes after the archive name
+                        if len(proc.cmdline()) > idx + 1:
+                            mount_point = proc.cmdline()[idx + 1]
+                            mount_points[archive_name] = mount_point
+                        break
+        except psutil._exceptions.ZombieProcess:
+            # Getting process details may fail (e.g. zombie process on macOS)
+            # Also see https://github.com/giampaolo/psutil/issues/783
+            continue
 
     return mount_points