FlatFile.rb in perobs-3.0.2

- old
+ new

@@ -114,10 +114,11 @@
         @f.flush
       rescue IOError => e
         PEROBS.log.fatal "Cannot sync flat file database: #{e.message}"
       end
       @index.sync
+      @space_list.sync
     end
 
     # Delete the blob for the specified ID.
     # @param id [Integer] ID of the object to be deleted
     # @return [Boolean] True if object was deleted, false otherwise
@@ -193,22 +194,29 @@
         if length != -1
           # Just a safeguard so we don't overwrite current data.
           header = FlatFileBlobHeader.read_at(@f, addr)
           if header.length != length
             PEROBS.log.fatal "Length in free list (#{length}) and header " +
-              "(#{header.length}) don't match."
+              "(#{header.length}) for address #{addr} don't match."
           end
           if raw_obj.length > header.length
             PEROBS.log.fatal "Object (#{raw_obj.length}) is longer than " +
               "blob space (#{header.length})."
           end
           if header.is_valid?
-            PEROBS.log.fatal "Entry (flags: #{header.flags}) is already used."
+            PEROBS.log.fatal "Entry at address #{addr} with flags: " +
+              "#{header.flags} is already used for ID #{header.id}."
           end
         end
         flags = 1 << FlatFileBlobHeader::VALID_FLAG_BIT
         flags |= (1 << FlatFileBlobHeader::COMPRESSED_FLAG_BIT) if compressed
+        if old_addr && old_header.is_marked?
+          # This method might be called in the middle of an operation that
+          # uses the mark flag. We must ensure that the flag is carried over
+          # to the new header.
+          flags |= (1 << FlatFileBlobHeader::MARK_FLAG_BIT)
+        end
         FlatFileBlobHeader.new(@f, addr, flags, raw_obj.length, id, crc).write
         @f.write(raw_obj)
         if length != -1 && raw_obj.length < length
           # The new object was not appended and it did not completely fill the
           # free space. So we have to write a new header to mark the remaining
@@ -223,19 +231,23 @@
           FlatFileBlobHeader.new(@f, space_address, 0, space_length,
                                  0, 0).write
           # Register the new space with the space list.
           @space_list.add_space(space_address, space_length) if space_length > 0
         end
+
+        # Once the blob has been written we can update the index as well.
+        @index.insert(id, addr)
+
         if old_addr
           # If we had an existing object stored for the ID we have to mark
           # this entry as deleted now.
           old_header.clear_flags
+          # And register the newly freed space with the space list.
+          @space_list.add_space(old_addr, old_header.length)
         else
           @f.flush
         end
-        # Once the blob has been written we can update the index as well.
-        @index.insert(id, addr)
       rescue IOError => e
         PEROBS.log.fatal "Cannot write blob for ID #{id} to FlatFileDB: " +
           e.message
       end
 
@@ -547,24 +559,34 @@
       @index.clear
       @space_list.clear
 
       each_blob_header do |pos, header|
         if header.is_valid?
-          @index.insert(header.id, pos)
+          if (duplicate_pos = @index.get(header.id))
+            PEROBS.log.error "FlatFile contains multiple blobs for ID " +
+              "#{header.id}. First blob is at address #{duplicate_pos}. " +
+              "Other blob found at address #{pos}."
+            @space_list.add_space(pos, header.length) if header.length > 0
+            discard_damaged_blob(header)
+          else
+            @index.insert(header.id, pos)
+          end
         else
           @space_list.add_space(pos, header.length) if header.length > 0
         end
       end
+
+      sync
     end
 
     def has_space?(address, size)
       header = FlatFileBlobHeader.read_at(@f, address)
-      header.length == size
+      !header.is_valid? && header.length == size
     end
 
     def has_id_at?(id, address)
       header = FlatFileBlobHeader.read_at(@f, address)
-      header.id == id
+      header.is_valid? && header.id == id
     end
 
     def inspect
       s = '['
       each_blob_header do |pos, header|