mmaped_file.rb in prometheus-client-mmap-0.7.0.beta20

- old
+ new

@@ -5,30 +5,10 @@
 module Prometheus
   module Client
     module Helper
       class MmapedFile < Mmap
         include EntryParser
-
-        class << self
-          def open(filepath)
-            MmapedFile.new(filepath, 'rw', Mmap::MAP_SHARED)
-          end
-
-          def ensure_exclusive_file(file_prefix = 'mmaped_file')
-            (0..Float::INFINITY).lazy
-              .map { |f_num| "#{file_prefix}_#{Prometheus::Client.pid}-#{f_num}.db" }
-              .map { |filename| File.join(Prometheus::Client.configuration.multiprocess_files_dir, filename) }
-              .find { |path| Helper::FileLocker.lock_to_process(path) }
-          end
-
-          def open_exclusive_file(file_prefix = 'mmaped_file')
-            filename = Helper::MmapedFile.ensure_exclusive_file(file_prefix)
-            open(filename)
-          end
-        end
-
-        MINIMUM_SIZE = 8
         attr_reader :filepath, :size
 
         def initialize(filepath, mode = 'r', protection = Mmap::MAP_SHARED, options = {})
           @filepath = filepath
 
@@ -39,15 +19,15 @@
 
           super(filepath, mode, protection, options)
         end
 
         def used=(value)
-          self[4..7] = [value].pack('l')
+          self[0..3] = [value].pack('l')
         end
 
         def add_entry(data, value)
-          self.used = 12 if used.zero?
+          self.used = START_POSITION if used.zero?
 
           # Pad to be 8-byte aligned.
           padded = data + (' ' * (8 - (data.length + 4) % 8))
           entry = [data.length, padded, value].pack("lA#{padded.length}d")
           used_ = used
@@ -68,9 +48,29 @@
 
         private
 
         def initial_mmap_file_size
           Prometheus::Client.configuration.initial_mmap_file_size
+        end
+
+        public
+
+        class << self
+          def open(filepath)
+            MmapedFile.new(filepath, 'rw', Mmap::MAP_SHARED)
+          end
+
+          def ensure_exclusive_file(file_prefix = 'mmaped_file')
+            (0..Float::INFINITY).lazy
+              .map { |f_num| "#{file_prefix}_#{Prometheus::Client.pid}-#{f_num}.db" }
+              .map { |filename| File.join(Prometheus::Client.configuration.multiprocess_files_dir, filename) }
+              .find { |path| Helper::FileLocker.lock_to_process(path) }
+          end
+
+          def open_exclusive_file(file_prefix = 'mmaped_file')
+            filename = Helper::MmapedFile.ensure_exclusive_file(file_prefix)
+            open(filename)
+          end
         end
       end
     end
   end
 end