yum: check whether the lock file disappeared

lib/ansible/module_utils/yumdnf.py

@@ -126,8 +126,9 @@ def __init__(self, module):
         # default isn't a bad idea
         self.lockfile = '/var/run/yum.pid'
 
+    @abstractmethod
     def is_lockfile_pid_valid(self):
-        raise NotImplementedError
+        return
 
     def _is_lockfile_present(self):
         return (os.path.isfile(self.lockfile) or glob.glob(self.lockfile)) and self.is_lockfile_pid_valid()

lib/ansible/modules/packaging/os/yum.py

@@ -413,38 +413,42 @@ def _enablerepos_with_error_checking(self, yumbase):
 
     def is_lockfile_pid_valid(self):
         try:
-            with open(self.lockfile, 'r') as f:
-                oldpid = int(f.readline())
-        except ValueError:
-            # invalid data
-            os.unlink(self.lockfile)
-            return False
-        except (IOError, OSError) as e:
-            self.module.fail_json(msg="Failure opening %s: %s" % (self.lockfile, to_native(e)))
-
-        if oldpid == os.getpid():
-            # that's us?
-            os.unlink(self.lockfile)
-            return False
-
-        try:
-            with open("/proc/%d/stat" % oldpid, 'r') as f:
-                stat = f.readline()
+            try:
+                with open(self.lockfile, 'r') as f:
+                    oldpid = int(f.readline())
+            except ValueError:
+                # invalid data
+                os.unlink(self.lockfile)
+                return False
 
-            if stat.split()[2] == 'Z':
-                # Zombie
+            if oldpid == os.getpid():
+                # that's us?
                 os.unlink(self.lockfile)
                 return False
-        except IOError:
+
             try:
-                os.kill(oldpid, 0)
-            except OSError as e:
-                if e.errno == errno.ESRCH:
-                    # No such process
+                with open("/proc/%d/stat" % oldpid, 'r') as f:
+                    stat = f.readline()
+
+                if stat.split()[2] == 'Z':
+                    # Zombie
                     os.unlink(self.lockfile)
                     return False
-
-                self.module.fail_json(msg="Unable to check PID %s in  %s: %s" % (oldpid, self.lockfile, to_native(e)))
+            except IOError:
+                # either /proc is not mounted or the process is already dead
+                try:
+                    # check the state of the process
+                    os.kill(oldpid, 0)
+                except OSError as e:
+                    if e.errno == errno.ESRCH:
+                        # No such process
+                        os.unlink(self.lockfile)
+                        return False
+
+                    self.module.fail_json(msg="Unable to check PID %s in  %s: %s" % (oldpid, self.lockfile, to_native(e)))
+        except (IOError, OSError) as e:
+            # lockfile disappeared?
+            return False
 
         # another copy seems to be running
         return True