Move default lockfile location (#103)

Summary:
`/var/lock/subsys` was meant for SysV startup serialization, and was
never the right location for our lockfile.

Moreover, recent systemd releases no longer keep the `legacy.conf`
configuration that creates `/var/lock/subsys`, so this means chefctl
no longer works out of the box.

Move the default to something more modern

*NOTE*: If Meta doesn't explicitly set a `lock_file` setting in their
`chefctl-config.rb`, they should before merging this.

Signed-off-by: Phil Dibowitz <phil@ipom.com>

Pull Request resolved: #103

Reviewed By: AadityaNair

Differential Revision: D113597252

Pulled By: dafyddcrosby

fbshipit-source-id: c9cf6759254ab95c911942391f06b4a89528d57b

Author: jaymzh

chefctl/sample_configs/chefctl-config.rb

@@ -40,7 +40,7 @@
 # immediate false
 
 # The lock file to use for chefctl.
-# lock_file '/var/lock/subsys/chefctl'
+# lock_file '/var/lock/chefctl.lock'
 
 # How long to wait for the lock to become available.
 # lock_time 1800

chefctl/src/chefctl.rb

@@ -150,7 +150,7 @@ module Config
     immediate false
 
     # The lock file to use for chefctl.
-    lock_file '/var/lock/subsys/chefctl'
+    lock_file '/var/lock/chefctl.lock'
 
     # How long to wait for the lock to become available.
     lock_time 1800

chefctl/src/spec/chefctl_spec.rb

@@ -92,7 +92,7 @@ def lib
     lockfile = double('lockfile')
 
     # open 'a+' done in wait_for_lock
-    allow(File).to receive(:open).with('/var/lock/subsys/chefctl', 'a+') { lockfile }
+    allow(File).to receive(:open).with('/var/lock/chefctl.lock', 'a+') { lockfile }
     allow(lockfile).to receive(:flock).and_return(true)
 
     allow(lockfile).to receive(:close)
@@ -106,29 +106,29 @@ def lib
   it 'can still acquire lock if first attempt fails' do
     # First failed attempt
     allow(Chefctl).
-      to receive_message_chain(:logger, :debug).with('Trying lock /var/lock/subsys/chefctl')
+      to receive_message_chain(:logger, :debug).with('Trying lock /var/lock/chefctl.lock')
     allow(main).to receive(:wait_for_lock).with(-1).and_return(false)
 
     # Second attempt
     expect(main).to receive(:wait_for_lock).with(1800).and_call_original # second attempt
 
     # Get pid of other lock file
     other_lockfile = double('other_lockfile')
-    expect(File).to receive(:open).with('/var/lock/subsys/chefctl', 'r').and_yield(other_lockfile)
+    expect(File).to receive(:open).with('/var/lock/chefctl.lock', 'r').and_yield(other_lockfile)
     expect(other_lockfile).to receive(:read).and_return('888888')
 
     expect(Chefctl).
       to receive_message_chain(:logger, :info).
-      with('/var/lock/subsys/chefctl is locked by 888888, waiting up to 1800 seconds.')
+      with('/var/lock/chefctl.lock is locked by 888888, waiting up to 1800 seconds.')
 
     # open 'a+' done in wait_for_lock
     lockfile = double('lockfile')
-    allow(File).to receive(:open).with('/var/lock/subsys/chefctl', 'a+') { lockfile }
+    allow(File).to receive(:open).with('/var/lock/chefctl.lock', 'a+') { lockfile }
     allow(lockfile).to receive(:flock).and_return(true)
 
     # taking over the lock
     expect(Chefctl).
-      to receive_message_chain(:logger, :debug).with('Lock acquired: /var/lock/subsys/chefctl')
+      to receive_message_chain(:logger, :debug).with('Lock acquired: /var/lock/chefctl.lock')
     expect(lockfile).to receive(:truncate)
     expect(Process).to receive(:pid).and_return('123123')
     expect(lockfile).to receive(:write).with('123123')
@@ -140,29 +140,29 @@ def lib
   it 'can still acquire lock if first attempt fails' do
     # First failed attempt
     allow(Chefctl).
-      to receive_message_chain(:logger, :debug).with('Trying lock /var/lock/subsys/chefctl')
+      to receive_message_chain(:logger, :debug).with('Trying lock /var/lock/chefctl.lock')
     allow(main).to receive(:wait_for_lock).with(-1).and_return(false)
 
     # Second attempt
     expect(main).to receive(:wait_for_lock).with(1800).and_call_original # second attempt
 
     # Get pid of other lock file
     other_lockfile = double('other_lockfile')
-    expect(File).to receive(:open).with('/var/lock/subsys/chefctl', 'r').and_yield(other_lockfile)
+    expect(File).to receive(:open).with('/var/lock/chefctl.lock', 'r').and_yield(other_lockfile)
     expect(other_lockfile).to receive(:read).and_return('888888')
 
     expect(Chefctl).
       to receive_message_chain(:logger, :info).
-      with('/var/lock/subsys/chefctl is locked by 888888, waiting up to 1800 seconds.')
+      with('/var/lock/chefctl.lock is locked by 888888, waiting up to 1800 seconds.')
 
     # open 'a+' done in wait_for_lock
     lockfile = double('lockfile')
-    allow(File).to receive(:open).with('/var/lock/subsys/chefctl', 'a+') { lockfile }
+    allow(File).to receive(:open).with('/var/lock/chefctl.lock', 'a+') { lockfile }
     allow(lockfile).to receive(:flock).and_return(true)
 
     # taking over the lock
     expect(Chefctl).
-      to receive_message_chain(:logger, :debug).with('Lock acquired: /var/lock/subsys/chefctl')
+      to receive_message_chain(:logger, :debug).with('Lock acquired: /var/lock/chefctl.lock')
     expect(lockfile).to receive(:truncate)
     expect(Process).to receive(:pid).and_return('123123')
     expect(lockfile).to receive(:write).with('123123')
@@ -174,30 +174,30 @@ def lib
   it 'does not crash on race between wait_for_lock and read on missing lockfile' do
     # First failed attempt
     allow(Chefctl).
-      to receive_message_chain(:logger, :debug).with('Trying lock /var/lock/subsys/chefctl')
+      to receive_message_chain(:logger, :debug).with('Trying lock /var/lock/chefctl.lock')
     allow(main).to receive(:wait_for_lock).with(-1).and_return(false)
 
     # Second attempt
     expect(main).to receive(:wait_for_lock).with(1800).and_call_original # second attempt
 
     # Attempt to get pid of other lock file
-    expect(File).to receive(:open).with('/var/lock/subsys/chefctl', 'r').and_raise(Errno::ENOENT)
+    expect(File).to receive(:open).with('/var/lock/chefctl.lock', 'r').and_raise(Errno::ENOENT)
     expect(Chefctl).
       to receive_message_chain(:logger, :info).
       with('Possible lockfile race, re-running wait_for_lock')
 
     expect(Chefctl).
       to receive_message_chain(:logger, :info).
-      with('/var/lock/subsys/chefctl is locked by another process, waiting up to 1800 seconds.')
+      with('/var/lock/chefctl.lock is locked by another process, waiting up to 1800 seconds.')
 
     # open 'a+' done in wait_for_lock
     lockfile = double('lockfile')
-    allow(File).to receive(:open).with('/var/lock/subsys/chefctl', 'a+') { lockfile }
+    allow(File).to receive(:open).with('/var/lock/chefctl.lock', 'a+') { lockfile }
     allow(lockfile).to receive(:flock).and_return(true)
 
     # taking over the lock
     expect(Chefctl).
-      to receive_message_chain(:logger, :debug).with('Lock acquired: /var/lock/subsys/chefctl')
+      to receive_message_chain(:logger, :debug).with('Lock acquired: /var/lock/chefctl.lock')
     expect(lockfile).to receive(:truncate)
     expect(Process).to receive(:pid).and_return('123123')
     expect(lockfile).to receive(:write).with('123123')
@@ -235,7 +235,7 @@ def lib
 
   it 'lock still yields the block when locking is disabled' do
     # Stub to prevent filesystem access if disable_locking guard fails
-    allow(File).to receive(:open).with('/var/lock/subsys/chefctl', anything).
+    allow(File).to receive(:open).with('/var/lock/chefctl.lock', anything).
       and_raise('locking should be disabled')
     yielded = false
     main.lock { yielded = true }