rolled custom daemon code to better match the way daemons are supposed to work under debian.

8 files changed, 282 insertions, 55 deletions

diff --git a/README.md b/README.md
index bc3a408..1546d57 100644
--- a/README.md
+++ b/README.md
@@ -27,8 +27,8 @@ For more details, see https://leap.se/nicknym
 Requirements
 ==================================
 
-Ruby 1.9
-CouchDB
+* Ruby 1.9
+* CouchDB
 
 Installation
 ==================================
@@ -59,23 +59,14 @@ The default HKP host is set to https://hkps.pool.sks-keyservers.net. The CA for
 Usage
 ==================================
 
-    Usage: nickserver <command> <options> -- <application options>
+    Usage: nickserver [OPTION] COMMAND
 
-    * where <command> is one of:
+    where COMMAND is one of:
       start         start an instance of the application
       stop          stop all instances of the application
       restart       stop all instances and restart them afterwards
-      reload        send a SIGHUP to all instances of the application
-      run           start the application and stay on top
-      zap           set the application to a stopped state
       status        show status (PID) of application instances
+      version       print version and exit
 
-    * and where <options> may contain several of the following:
-
-        -t, --ontop                      Stay on top (does not daemonize)
-        -f, --force                      Force operation
-        -n, --no_wait                    Do not wait for processes to stop
-
-    Common options:
-        -h, --help                       Show this message
-            --version                    Show version
+    where OPTION is one of:
+      --verbose     log more
\ No newline at end of file
diff --git a/bin/nickserver b/bin/nickserver
index b0cabac..de4a818 100755
--- a/bin/nickserver
+++ b/bin/nickserver
@@ -1,4 +1,5 @@
 #!/usr/bin/ruby
+
 #
 # Nickserver key discovery daemon
 #
@@ -19,40 +20,8 @@ rescue LoadError
   end
 end
 
-#
-# Handle craceful Ctrl-C
-#
-Signal.trap("SIGINT") do
-  puts "\nQuit"
-  exit
-end
-
-#
-# Handle '--version' ourselves
-#
-if ARGV.grep(/--version/).any?
-  puts "nickserver #{Nickserver::VERSION}, ruby #{RUBY_VERSION}"
-  exit(0)
-end
-
-#
-# Start the daemon
-#
-require 'daemons'
-
-options = {:app_name => 'nickserver', :multiple => false, :backtrace => true}
-
-# pick where the pid file should go (must be readable/writable by current user)
-if File.writable?('/var/run/nickserver')
-  options.merge!(:dir_mode => :normal, :dir => '/var/run/nickserver')
-elsif ENV["USER"] == "root"
-  options.merge!(:dir_mode => :system)
-else
-  options.merge!(:dir_mode => :normal, :dir => '/tmp')
-end
-
-Daemons.run_proc('nickserver', options) do
+Nickserver::Daemon.run do
   EventMachine.run do
     Nickserver::Server.start
   end
-end
+end
\ No newline at end of file
diff --git a/config/default.yml b/config/default.yml
index 83bfa48..4328cbd 100644
--- a/config/default.yml
+++ b/config/default.yml
@@ -5,3 +5,6 @@ couch_database: 'users'
 #couch_password: 'blahblah'
 hkp_url: 'https://hkps.pool.sks-keyservers.net:/pks/lookup'
 port: 6425
+pid_file: '/var/run/nickserver'
+user: 'nobody'
+log_file: '/var/log/nickserver.log'
diff --git a/lib/nickserver.rb b/lib/nickserver.rb
index f97a95f..9e6464e 100644
--- a/lib/nickserver.rb
+++ b/lib/nickserver.rb
@@ -9,4 +9,4 @@ require "nickserver/hkp/fetch_key_info"
 require "nickserver/hkp/fetch_key"
 
 require "nickserver/server"
-
+require "nickserver/daemon"
diff --git a/lib/nickserver/config.rb b/lib/nickserver/config.rb
index 3f92186..b283d8b 100644
--- a/lib/nickserver/config.rb
+++ b/lib/nickserver/config.rb
@@ -15,7 +15,12 @@ module Nickserver
       attr_accessor :couch_user
       attr_accessor :couch_password
       attr_accessor :port
+      attr_accessor :pid_file
+      attr_accessor :user
+      attr_accessor :log_file
+
       attr_accessor :loaded
+      attr_accessor :verbose
     end
 
     def self.load
@@ -39,9 +44,9 @@ module Nickserver
             exit(1)
           end
         end
-        puts "Loaded #{file_path}"
+        puts "Loaded #{file_path}" if Config.verbose
       rescue Errno::ENOENT => exc
-        puts "Skipping #{file_path}"
+        puts "Skipping #{file_path}" if Config.verbose
       rescue Exception => exc
         STDERR.puts exc.inspect
         exit(1)
diff --git a/lib/nickserver/daemon.rb b/lib/nickserver/daemon.rb
new file mode 100644
index 0000000..9eb2ff5
--- /dev/null
+++ b/lib/nickserver/daemon.rb
@@ -0,0 +1,260 @@
+require 'etc'
+require 'fileutils'
+
+#
+# A simple daemon, in a Debian style. Adapted from gem Dante.
+#
+
+module Nickserver
+  class Daemon
+
+    def self.run(&block)
+      self.new.run(&block)
+    end
+
+    def run(&block)
+      parse_options
+      Config.load
+      send("command_#{@command}", &block)
+    end
+
+    private
+
+    MAX_WAIT = 2
+
+    #
+    # PERMISSIONS
+    #
+
+    #
+    # see http://timetobleed.com/5-things-you-dont-know-about-user-ids-that-will-destroy-you/
+    # (hint: it is easy to get it wrong)
+    #
+    def drop_permissions_to(username)
+      if username != 'root'
+        if Process::Sys.getuid == 0
+          Process::Sys.setuid(Etc.getpwnam(username).uid)
+          if root?
+            bail "failed to drop permissions"
+          end
+        else
+          bail "cannot change process uid to #{username}"
+        end
+      end
+    end
+
+    def root?
+      begin
+        Process::Sys.setuid(0)
+      rescue Errno::EPERM
+        false
+      else
+        true
+      end
+    end
+
+    #
+    # PROCESS STUFF
+    #
+
+    def daemonize
+      return bail("Process is already started") if daemon_running?
+      pid = fork do
+        exit if fork
+        Process.setsid
+        exit if fork
+        create_pid_file(Config.pid_file, Config.user)
+        catch_interrupt
+        redirect_output
+        drop_permissions_to(Config.user)
+        File.umask 0000
+        yield
+      end
+
+      if until_true { daemon_running? }
+        puts "Daemon has started successfully"
+        exit(0)
+      else # Failed to start
+        puts "Daemon couldn't be started"
+        exit(1)
+      end
+    end
+
+    def create_pid_file(file, user)
+      File.open file, 'w' do |f|
+        f.write("#{Process.pid}\n")
+      end
+      FileUtils.chown(user, nil, file)
+    rescue Errno::EACCES
+      bail "insufficient permission to create to pid file `#{file}`"
+    rescue Errno::ENOENT
+      bail "bad path for pid file `#{file}`"
+    rescue Errno::EROFS
+      bail "can't create pid file `#{file}` on read-only filesystem"
+    end
+
+    def daemon_running?
+      return false unless File.exist?(Config.pid_file)
+      Process.kill 0, File.read(Config.pid_file).to_i
+      true
+    rescue Errno::ESRCH
+      false
+    end
+
+    def pid_from_file(file)
+      pid = IO.read(file).chomp
+      if pid != ""
+        pid.to_i
+      else
+        nil
+      end
+    end
+
+    def kill_pid
+      file = Config.pid_file
+      if File.exists?(file)
+        pid = pid_from_file(file)
+        if pid
+          Process.kill('TERM', pid)
+          puts "Stopped #{pid}"
+        else
+          bail "Error reading pid file #{file}"
+        end
+        begin
+          FileUtils.rm Config.pid_file
+        rescue Errno::EACCES
+          bail 'insufficient permission to remove pid file'
+        end
+      else
+        bail "could not find pid file #{file}"
+      end
+    rescue => e
+      puts "Failed to stop: #{e}"
+    end
+
+    #
+    # Gracefully handle Ctrl-C
+    #
+    def catch_interrupt
+      Signal.trap("SIGINT") do
+        command_stop
+        $stdout.puts "\nQuit"
+        $stdout.flush
+        exit
+      end
+    end
+
+
+    #
+    # OUTPUT
+    #
+
+    def usage(msg)
+      puts msg
+      puts
+      puts "Usage: nickserver [OPTION] COMMAND"
+      puts "COMMAND is one of: start, stop, restart, status, version"
+      puts "OPTION is one of: --verbose"
+      puts
+      exit 1
+    end
+
+    def bail(msg)
+      puts "Nickserver ERROR: #{msg}."
+      puts "Bailing out."
+      exit(1)
+    end
+
+    #
+    # Redirect output based on log settings (reopens stdout/stderr to specified logfile)
+    # If log_path is nil, redirect to /dev/null to quiet output
+    #
+    def redirect_output
+      if log_path = Config.log_file
+        FileUtils.mkdir_p File.dirname(log_path), :mode => 0755
+        FileUtils.touch log_path
+        File.chmod(0644, log_path)
+        $stdout.reopen(log_path, 'a')
+        $stderr.reopen $stdout
+        $stdout.sync = true
+      else
+        # redirect to /dev/null
+        $stdin.reopen '/dev/null'
+        $stdout.reopen '/dev/null', 'a'
+        $stderr.reopen $stdout
+      end
+    rescue Errno::EACCES
+      bail "no permission to create log file #{log_path}"
+    end
+
+    #
+    # UTILITY
+    #
+
+    #
+    # Runs until the block condition is met or the timeout_seconds is exceeded
+    # until_true(10) { ...return_condition... }
+    #
+    def until_true(timeout_seconds=MAX_WAIT, &block)
+      elapsed_seconds = 0
+      interval = 0.5
+      while elapsed_seconds < timeout_seconds && block.call != true
+        elapsed_seconds += interval
+        sleep(interval)
+      end
+      elapsed_seconds < timeout_seconds
+    end
+
+    def parse_options
+      loop do
+        case ARGV[0]
+          when 'start'     then ARGV.shift; @command = :start
+          when 'stop'      then ARGV.shift; @command = :stop
+          when 'restart'   then ARGV.shift; @command = :restart
+          when 'status'    then ARGV.shift; @command = :status
+          when 'version'   then ARGV.shift; @command = :version
+          when '--verbose' then ARGV.shift; Config.versbose = true
+          when /^-/        then usage("Unknown option: #{ARGV[0].inspect}")
+          else break
+        end
+      end
+      usage("Missing command") unless @command
+    end
+
+    #
+    # COMMANDS
+    #
+
+    def command_version
+      puts "nickserver #{Nickserver::VERSION}, ruby #{RUBY_VERSION}"
+      exit(0)
+    end
+
+    def command_start(&block)
+      daemonize(&block)
+    end
+
+    def command_stop
+      if daemon_running?
+        kill_pid
+        until_true { !daemon_running? }
+      else
+        puts "No processes are running"
+      end
+    end
+
+    def command_restart(&block)
+      command_stop
+      command_start(&block)
+    end
+
+    def command_status
+      if daemon_running?
+        puts "Process id #{pid_from_file(Config.pid_file)}"
+      else
+        puts 'Not running'
+      end
+    end
+
+  end
+end
diff --git a/lib/nickserver/version.rb b/lib/nickserver/version.rb
index 799ca6c..6e86d39 100644
--- a/lib/nickserver/version.rb
+++ b/lib/nickserver/version.rb
@@ -1,3 +1,3 @@
 module Nickserver
-  VERSION = "0.0.1"
+  VERSION = "0.2.0"
 end
diff --git a/nickserver.gemspec b/nickserver.gemspec
index 2c87585..5d0d807 100644
--- a/nickserver.gemspec
+++ b/nickserver.gemspec
@@ -24,5 +24,4 @@ Gem::Specification.new do |gem|
   gem.add_dependency 'eventmachine'
   gem.add_dependency 'em-http-request'
   gem.add_dependency 'eventmachine_httpserver'
-  gem.add_dependency 'daemons'
 end