path: root/lib/puppet/util.rb

# A module to collect utility functions.

require 'puppet/util/monkey_patches'
require 'sync'
require 'puppet/external/lock'
require 'monitor'
require 'puppet/util/execution_stub'

module Puppet
  # A command failed to execute.
  require 'puppet/error'
  class ExecutionFailure < Puppet::Error
  end
module Util
  require 'benchmark'

  # These are all for backward compatibility -- these are methods that used
  # to be in Puppet::Util but have been moved into external modules.
  require 'puppet/util/posix'
  extend Puppet::Util::POSIX

  @@sync_objects = {}.extend MonitorMixin

  def self.activerecord_version
    if (defined?(::ActiveRecord) and defined?(::ActiveRecord::VERSION) and defined?(::ActiveRecord::VERSION::MAJOR) and defined?(::ActiveRecord::VERSION::MINOR))
      ([::ActiveRecord::VERSION::MAJOR, ::ActiveRecord::VERSION::MINOR].join('.').to_f)
    else
      0
    end
  end

  
  def self.synchronize_on(x,type)
    sync_object,users = 0,1
    begin
      @@sync_objects.synchronize { 
        (@@sync_objects[x] ||= [Sync.new,0])[users] += 1
      }
      @@sync_objects[x][sync_object].synchronize(type) { yield }
    ensure
      @@sync_objects.synchronize { 
        @@sync_objects.delete(x) unless (@@sync_objects[x][users] -= 1) > 0
      }
    end
  end

  # Change the process to a different user
  def self.chuser
    if group = Puppet[:group]
      group = self.gid(group)
      raise Puppet::Error, "No such group #{Puppet[:group]}" unless group
      unless Puppet::Util::SUIDManager.gid == group
        begin
          Puppet::Util::SUIDManager.egid = group
          Puppet::Util::SUIDManager.gid = group
        rescue => detail
          Puppet.warning "could not change to group #{group.inspect}: #{detail}"
          $stderr.puts "could not change to group #{group.inspect}"

          # Don't exit on failed group changes, since it's
          # not fatal
          #exit(74)
        end
      end
    end

    if user = Puppet[:user]
      user = self.uid(user)
      raise Puppet::Error, "No such user #{Puppet[:user]}" unless user
      unless Puppet::Util::SUIDManager.uid == user
        begin
          Puppet::Util::SUIDManager.initgroups(user)
          Puppet::Util::SUIDManager.uid = user
          Puppet::Util::SUIDManager.euid = user
        rescue => detail
          $stderr.puts "Could not change to user #{user}: #{detail}"
          exit(74)
        end
      end
    end
  end

  # Create instance methods for each of the log levels.  This allows
  # the messages to be a little richer.  Most classes will be calling this
  # method.
  def self.logmethods(klass, useself = true)
    Puppet::Util::Log.eachlevel { |level|
      klass.send(:define_method, level, proc { |args|
        args = args.join(" ") if args.is_a?(Array)
        if useself

          Puppet::Util::Log.create(

            :level => level,
            :source => self,

            :message => args
          )
        else

          Puppet::Util::Log.create(

            :level => level,

            :message => args
          )
        end
      })
    }
  end

  # Proxy a bunch of methods to another object.
  def self.classproxy(klass, objmethod, *methods)
    classobj = class << klass; self; end
    methods.each do |method|
      classobj.send(:define_method, method) do |*args|
        obj = self.send(objmethod)

        obj.send(method, *args)
      end
    end
  end

  # Proxy a bunch of methods to another object.
  def self.proxy(klass, objmethod, *methods)
    methods.each do |method|
      klass.send(:define_method, method) do |*args|
        obj = self.send(objmethod)

        obj.send(method, *args)
      end
    end
  end

  # XXX this should all be done using puppet objects, not using
  # normal mkdir
  def self.recmkdir(dir,mode = 0755)
    if FileTest.exist?(dir)
      return false
    else
      tmp = dir.sub(/^\//,'')
      path = [File::SEPARATOR]
      tmp.split(File::SEPARATOR).each { |dir|
        path.push dir
        if ! FileTest.exist?(File.join(path))
          Dir.mkdir(File.join(path), mode)
        elsif FileTest.directory?(File.join(path))
          next
        else FileTest.exist?(File.join(path))
          raise "Cannot create #{dir}: basedir #{File.join(path)} is a file"
        end
      }
      return true
    end
  end

  # Execute a given chunk of code with a new umask.
  def self.withumask(mask)
    cur = File.umask(mask)

    begin
      yield
    ensure
      File.umask(cur)
    end
  end

  def benchmark(*args)
    msg = args.pop
    level = args.pop
    object = nil

    if args.empty?
      if respond_to?(level)
        object = self
      else
        object = Puppet
      end
    else
      object = args.pop
    end

    raise Puppet::DevError, "Failed to provide level to :benchmark" unless level

    unless level == :none or object.respond_to? level
      raise Puppet::DevError, "Benchmarked object does not respond to #{level}"
    end

    # Only benchmark if our log level is high enough
    if level != :none and Puppet::Util::Log.sendlevel?(level)
      result = nil
      seconds = Benchmark.realtime {
        yield
      }
      object.send(level, msg + (" in %0.2f seconds" % seconds))
      return seconds
    else
      yield
    end
  end

  def which(bin)
    if bin =~ /^\//
      return bin if FileTest.file? bin and FileTest.executable? bin
    else
      ENV['PATH'].split(File::PATH_SEPARATOR).each do |dir|
        dest=File.join(dir, bin)
        return dest if FileTest.file? dest and FileTest.executable? dest
      end
    end
    nil
  end
  module_function :which

  # Execute the provided command in a pipe, yielding the pipe object.
  def execpipe(command, failonfail = true)
    if respond_to? :debug
      debug "Executing '#{command}'"
    else
      Puppet.debug "Executing '#{command}'"
    end

    output = open("| #{command} 2>&1") do |pipe|
      yield pipe
    end

    if failonfail
      unless $CHILD_STATUS == 0
        raise ExecutionFailure, output
      end
    end

    output
  end

  def execfail(command, exception)
      output = execute(command)
      return output
  rescue ExecutionFailure
      raise exception, output
  end

  # Execute the desired command, and return the status and output.
  # def execute(command, failonfail = true, uid = nil, gid = nil)
  # :combine sets whether or not to combine stdout/stderr in the output
  # :stdinfile sets a file that can be used for stdin. Passing a string
  # for stdin is not currently supported.
  def execute(command, arguments = {:failonfail => true, :combine => true})
    if command.is_a?(Array)
      command = command.flatten.collect { |i| i.to_s }
      str = command.join(" ")
    else
      # We require an array here so we know where we're incorrectly
      # using a string instead of an array.  Once everything is
      # switched to an array, we might relax this requirement.
      raise ArgumentError, "Must pass an array to execute()"
    end

    if respond_to? :debug
      debug "Executing '#{str}'"
    else
      Puppet.debug "Executing '#{str}'"
    end

    arguments[:uid] = Puppet::Util::SUIDManager.convert_xid(:uid, arguments[:uid]) if arguments[:uid]
    arguments[:gid] = Puppet::Util::SUIDManager.convert_xid(:gid, arguments[:gid]) if arguments[:gid]

    if execution_stub = Puppet::Util::ExecutionStub.current_value
      return execution_stub.call(command, arguments)
    end

    @@os ||= Facter.value(:operatingsystem)
    output = nil
    child_pid, child_status = nil
    # There are problems with read blocking with badly behaved children
    # read.partialread doesn't seem to capture either stdout or stderr
    # We hack around this using a temporary file

    # The idea here is to avoid IO#read whenever possible.
    output_file="/dev/null"
    error_file="/dev/null"
    if ! arguments[:squelch]
      require "tempfile"
      output_file = Tempfile.new("puppet")
      error_file=output_file if arguments[:combine]
    end

    if Puppet.features.posix?
      oldverb = $VERBOSE
      $VERBOSE = nil
      child_pid = Kernel.fork
      $VERBOSE = oldverb
      if child_pid
        # Parent process executes this
        child_status = (Process.waitpid2(child_pid)[1]).to_i >> 8
      else
        # Child process executes this
        Process.setsid
        begin
          if arguments[:stdinfile]
            $stdin.reopen(arguments[:stdinfile])
          else
            $stdin.reopen("/dev/null")
          end
          $stdout.reopen(output_file)
          $stderr.reopen(error_file)

          3.upto(256){|fd| IO::new(fd).close rescue nil}
          if arguments[:gid]
            Process.egid = arguments[:gid]
            Process.gid = arguments[:gid] unless @@os == "Darwin"
          end
          if arguments[:uid]
            Process.euid = arguments[:uid]
            Process.uid = arguments[:uid] unless @@os == "Darwin"
          end
          ENV['LANG'] = ENV['LC_ALL'] = ENV['LC_MESSAGES'] = ENV['LANGUAGE'] = 'C'
          if command.is_a?(Array)
            Kernel.exec(*command)
          else
            Kernel.exec(command)
          end
        rescue => detail
          puts detail.to_s
          exit!(1)
        end
      end
    elsif Puppet.features.microsoft_windows?
      command = command.collect {|part| '"' + part.gsub(/"/, '\\"') + '"'}.join(" ") if command.is_a?(Array)
      Puppet.debug "Creating process '#{command}'"
      processinfo = Process.create( :command_line => command )
      child_status = (Process.waitpid2(child_pid)[1]).to_i >> 8
    end

    # read output in if required
    if ! arguments[:squelch]

      # Make sure the file's actually there.  This is
      # basically a race condition, and is probably a horrible
      # way to handle it, but, well, oh well.
      unless FileTest.exists?(output_file.path)
        Puppet.warning "sleeping"
        sleep 0.5
        unless FileTest.exists?(output_file.path)
          Puppet.warning "sleeping 2"
          sleep 1
          unless FileTest.exists?(output_file.path)
            Puppet.warning "Could not get output"
            output = ""
          end
        end
      end
      unless output
        # We have to explicitly open here, so that it reopens
        # after the child writes.
        output = output_file.open.read

        # The 'true' causes the file to get unlinked right away.
        output_file.close(true)
      end
    end

    if arguments[:failonfail]
      unless child_status == 0
        raise ExecutionFailure, "Execution of '#{str}' returned #{child_status}: #{output}"
      end
    end

    output
  end

  module_function :execute

  # Create an exclusive lock.
  def threadlock(resource, type = Sync::EX)
    Puppet::Util.synchronize_on(resource,type) { yield }
  end

  # Because some modules provide their own version of this method.
  alias util_execute execute

  module_function :benchmark

  def memory
    unless defined?(@pmap)
      @pmap = which('pmap')
    end
    if @pmap
      %x{#{@pmap} #{Process.pid}| grep total}.chomp.sub(/^\s*total\s+/, '').sub(/K$/, '').to_i
    else
      0
    end
  end

  def symbolize(value)
    if value.respond_to? :intern
      value.intern
    else
      value
    end
  end

  def symbolizehash(hash)
    newhash = {}
    hash.each do |name, val|
      if name.is_a? String
        newhash[name.intern] = val
      else
        newhash[name] = val
      end
    end
  end

  def symbolizehash!(hash)
    hash.each do |name, val|
      if name.is_a? String
        hash[name.intern] = val
        hash.delete(name)
      end
    end

    hash
  end
  module_function :symbolize, :symbolizehash, :symbolizehash!

  # Just benchmark, with no logging.
  def thinmark
    seconds = Benchmark.realtime {
      yield
    }

    seconds
  end

  module_function :memory, :thinmark

  def secure_open(file,must_be_w,&block)
    raise Puppet::DevError,"secure_open only works with mode 'w'" unless must_be_w == 'w'
    raise Puppet::DevError,"secure_open only requires a block"    unless block_given?
    Puppet.warning "#{file} was a symlink to #{File.readlink(file)}" if File.symlink?(file)
    if File.exists?(file) or File.symlink?(file)
      wait = File.symlink?(file) ? 5.0 : 0.1
      File.delete(file)
      sleep wait # give it a chance to reappear, just in case someone is actively trying something.
    end
    begin
      File.open(file,File::CREAT|File::EXCL|File::TRUNC|File::WRONLY,&block)
    rescue Errno::EEXIST
      desc = File.symlink?(file) ? "symlink to #{File.readlink(file)}" : File.stat(file).ftype
      puts "Warning: #{file} was apparently created by another process (as"
      puts "a #{desc}) as soon as it was deleted by this process.  Someone may be trying"
      puts "to do something objectionable (such as tricking you into overwriting system"
      puts "files if you are running as root)."
      raise
    end
  end
  module_function :secure_open
end
end

require 'puppet/util/errors'
require 'puppet/util/methodhelper'
require 'puppet/util/metaid'
require 'puppet/util/classgen'
require 'puppet/util/docs'
require 'puppet/util/execution'
require 'puppet/util/logging'
require 'puppet/util/package'
require 'puppet/util/warnings'