Class: Chef::Daemon

Inherits:
Object show all
Defined in:
lib/chef/daemon.rb

Class Attribute Summary collapse

Class Method Summary collapse

Class Attribute Details

.name ⇒ Object

Returns the value of attribute name.



26
27
28
 
# File 'lib/chef/daemon.rb', line 26

def name
  @name
end

Class Method Details

._change_privilege(user, group = user) ⇒ Object

Change privileges of the process to be the specified user and group

Parameters

user<String>

The user to change the process to.

group<String>

The group to change the process to.

Alternatives

If group is left out, the user will be used (changing to user:user)



159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
 
# File 'lib/chef/daemon.rb', line 159

def _change_privilege(user, group=user)
  uid, gid = Process.euid, Process.egid

  begin
    target_uid = Etc.getpwnam(user).uid
  rescue ArgumentError => e
    Chef::Application.fatal!("Failed to get UID for user #{user}, does it exist? #{e.message}")
    return false
  end
   
  begin
    target_gid = Etc.getgrnam(group).gid
  rescue ArgumentError => e
    Chef::Application.fatal!("Failed to get GID for group #{group}, does it exist? #{e.message}")
    return false
  end

  if (uid != target_uid) or (gid != target_gid)
    Process.initgroups(user, target_gid)
    Process::GID.change_privilege(target_gid)
    Process::UID.change_privilege(target_uid)
  end
  true
rescue Errno::EPERM => e
  Chef::Application.fatal!("Permission denied when trying to change #{uid}:#{gid} to #{target_uid}:#{target_gid}. #{e.message}")
end

.change_privilege ⇒ Object

Change process user/group to those specified in Chef::Config



138
139
140
141
142
143
144
145
146
147
148
 
# File 'lib/chef/daemon.rb', line 138

def change_privilege
  Dir.chdir("/")

  if Chef::Config[:user] and Chef::Config[:group]
    Chef::Log.info("About to change privilege to #{Chef::Config[:user]}:#{Chef::Config[:group]}")
    _change_privilege(Chef::Config[:user], Chef::Config[:group])
  elsif Chef::Config[:user]
    Chef::Log.info("About to change privilege to #{Chef::Config[:user]}")
    _change_privilege(Chef::Config[:user])
  end
end

.daemonize(name) ⇒ Object

Daemonize the current process, managing pidfiles and process uid/gid

Parameters

name<String>

The name to be used for the pid file



33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
 
# File 'lib/chef/daemon.rb', line 33

def daemonize(name)
  @name = name
  pid = pid_from_file
  unless running?
    remove_pid_file()
    Chef::Log.info("Daemonizing..")
    begin
      exit if fork
      Process.setsid
      exit if fork
      Chef::Log.info("Forked, in #{Process.pid}. Privileges: #{Process.euid} #{Process.egid}")
      File.umask Chef::Config[:umask]
      $stdin.reopen("/dev/null")
      $stdout.reopen("/dev/null", "a")
      $stderr.reopen($stdout)
      save_pid_file
      at_exit {
        Chef::Log.debug("daemon pid #{Process.pid} in at_exit handler")
        remove_pid_file
      }
    rescue NotImplementedError => e
      Chef::Application.fatal!("There is no fork: #{e.message}")
    end
  else
    Chef::Application.fatal!("Chef is already running pid #{pid}")
  end
end

.pid_file ⇒ Object

Gets the pid file for @name

Returns

String

Location of the pid file for @name



84
85
86
 
# File 'lib/chef/daemon.rb', line 84

def pid_file
   Chef::Config[:pid_file] or "/tmp/#{@name}.pid"
end

.pid_from_file ⇒ Object

Suck the pid out of pid_file

Returns

Integer

The PID from pid_file

nil

Returned if the pid_file does not exist.



95
96
97
98
99
 
# File 'lib/chef/daemon.rb', line 95

def pid_from_file
  File.read(pid_file).chomp.to_i
rescue Errno::ENOENT, Errno::EACCES
  nil
end

.remove_pid_file ⇒ Object

Delete the PID from the filesystem



122
123
124
125
126
127
128
129
130
131
132
133
134
 
# File 'lib/chef/daemon.rb', line 122

def remove_pid_file
  return unless File.exists?(pid_file)

  daemon_pid = pid_from_file
  my_pid = Process.pid
  if daemon_pid != my_pid
    Chef::Log.debug("My pid is #{my_pid}; not removing #{pid_file} which contains #{daemon_pid}")
    return
  end

  FileUtils.rm(pid_file)
  Chef::Log.debug("Removed #{pid_file}")
end

.running? ⇒ Boolean

Check if Chef is running based on the pid_file

Returns

Boolean

True if Chef is running False if Chef is not running

Returns:

  • (Boolean) 


67
68
69
70
71
72
73
74
75
76
77
78
 
# File 'lib/chef/daemon.rb', line 67

def running?
  if pid_from_file.nil?
    false
  else
    Process.kill(0, pid_from_file)
    true
  end
rescue Errno::ESRCH, Errno::ENOENT
  false
rescue Errno::EACCES => e
  Chef::Application.fatal!("You don't have access to the PID file at #{pid_file}: #{e.message}")
end

.save_pid_file ⇒ Object

Store the PID on the filesystem This uses the Chef::Config option, or “/tmp/name.pid” otherwise



104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
 
# File 'lib/chef/daemon.rb', line 104

def save_pid_file
  file = pid_file
  begin
    FileUtils.mkdir_p(File.dirname(file))
  rescue Errno::EACCES => e
    Chef::Application.fatal!("Failed store pid in #{File.dirname(file)}, permission denied: #{e.message}")
  end

  begin
    pid = Process.pid.to_s
    File.open(file, "w") { |f| f.write(pid) }
    Chef::Log.debug("Wrote #{pid} to #{file}")
  rescue Errno::EACCES => e
    Chef::Application.fatal!("Couldn't write to pidfile #{file}, permission denied: #{e.message}")
  end
end