bugfix: lock file now actually periodically touched; also some minor text and code...

[sup] / lib / sup / util.rb

diff --git a/lib/sup/util.rb b/lib/sup/util.rb
index c9ac70c2473fd706158db21704f3fc7bd594cde5..8f6680e6eeaa58a065f38d6b7b7e6c6a439defef 100644 (file)
--- a/lib/sup/util.rb
+++ b/lib/sup/util.rb
@@ -1,3 +1,39 @@
+require 'lockfile'
+
+## time for some monkeypatching!
+class Lockfile
+  def gen_lock_id
+    Hash[
+         'host' => "#{ Socket.gethostname }",
+         'pid' => "#{ Process.pid }",
+         'ppid' => "#{ Process.ppid }",
+         'time' => timestamp,
+         'pname' => $0,
+         'user' => ENV["USER"]
+        ]
+  end
+
+  def dump_lock_id lock_id = @lock_id
+      "host: %s\npid: %s\nppid: %s\ntime: %s\nuser: %s\npname: %s\n" %
+        lock_id.values_at('host','pid','ppid','time','user', 'pname')
+    end
+
+  def lockinfo_on_disk
+    h = load_lock_id IO.read(path)
+    h['mtime'] = File.mtime path
+    h
+  end
+
+  def touch_yourself; touch path end
+end
+
+class Range
+  ## only valid for integer ranges (unless I guess it's exclusive)
+  def size 
+    last - first + (exclude_end? ? 0 : 1)
+  end
+end
+
 class Module
   def bool_reader *args
     args.each { |sym| class_eval %{ def #{sym}?; @#{sym}; end } }
@@ -9,7 +45,10 @@ class Module
   end
 
   def defer_all_other_method_calls_to obj
-    class_eval %{ def method_missing meth, *a, &b; @#{obj}.send meth, *a, &b; end }
+    class_eval %{
+      def method_missing meth, *a, &b; @#{obj}.send meth, *a, &b; end
+      def respond_to? meth; @#{obj}.respond_to?(meth); end
+    }
   end
 end
 
@@ -263,11 +302,12 @@ end
 ## allows for constructors that take arguments.
 ##
 ## You must have #initialize call "self.class.i_am_the_instance self"
-## at some point or everything will fail horribly
+## at some point or everything will fail horribly.
 module Singleton
   module ClassMethods
     def instance; @instance; end
     def instantiated?; defined?(@instance) && !@instance.nil?; end
+    def deinstantiate!; @instance = nil; end
     def method_missing meth, *a, &b
       raise "no instance defined!" unless defined? @instance
       @instance.send meth, *a, &b
@@ -282,3 +322,70 @@ module Singleton
     klass.extend ClassMethods
   end
 end
+
+## wraps an object. if it throws an exception, keeps a copy, and
+## rethrows it for any further method calls.
+class Recoverable
+  def initialize o
+    @o = o
+    @e = nil
+  end
+
+  def clear_error!; @e = nil; end
+  def has_errors?; !@e.nil?; end
+  def error; @e; end
+
+  def method_missing m, *a, &b; __pass m, *a, &b; end
+  
+  def id; __pass :id; end
+  def to_s; __pass :to_s; end
+  def to_yaml x; __pass :to_yaml, x; end
+  def is_a? c; @o.is_a? c; end
+
+  def respond_to? m; @o.respond_to? m end
+
+  def __pass m, *a, &b
+    begin
+      @o.send(m, *a, &b)
+    rescue Exception => e
+      @e = e
+      raise e
+    end
+  end
+end
+
+## acts like a hash with an initialization block, but saves any
+## newly-created value even upon lookup.
+##
+## for example:
+##
+## class C
+##   attr_accessor :val
+##   def initialize; @val = 0 end
+## end
+## 
+## h = Hash.new { C.new }
+## h[:a].val # => 0
+## h[:a].val = 1
+## h[:a].val # => 0
+##
+## h2 = SavingHash.new { C.new }
+## h2[:a].val # => 0
+## h2[:a].val = 1
+## h2[:a].val # => 1
+##
+## important note: you REALLY want to use #member? to test existence,
+## because just checking h[anything] will always evaluate to true
+## (except for degenerate constructor blocks that return nil or false)
+class SavingHash
+  def initialize &b
+    @constructor = b
+    @hash = Hash.new
+  end
+
+  def [] k
+    @hash[k] ||= @constructor.call(k)
+  end
+
+  defer_all_other_method_calls_to :hash
+end