Put updated copyright statements in all source files.

[cumulus.git] / ref.h

diff --git a/ref.h b/ref.h
index cc21a5a..deae39c 100644 (file)
--- a/ref.h
+++ b/ref.h
@@ -1,7 +1,24 @@
-/* LBS: An LFS-inspired filesystem backup system
- * Copyright (C) 2007  Michael Vrable
+/* Cumulus: Smart Filesystem Backup to Dumb Servers
  *
- * Backups are structured as a collection of objects, which may refer to other
+ * Copyright (C) 2007-2008  The Regents of the University of California
+ * Written by Michael Vrable <mvrable@cs.ucsd.edu>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/* Backups are structured as a collection of objects, which may refer to other
  * objects.  Object references are used to name other objects or parts of them.
  * This file defines the class for representing object references and the
  * textual representation of these references. */
@@ -39,7 +56,8 @@
  * range specifier is given, then by default the entire object is used.
  *    <range> ::= <start> "+" <length>
  * Both <start> and <length> are decimal values.  If included, the range is
- * enclosed in brackets.
+ * enclosed in brackets.  As an abbreviation, if <start> is 0 then the range
+ * can be given as just <length> (no "+" needed).
  *
  * When both a checksum and a range are included, note that the checksum is
  * taken over the entire original object, before the range is taken into
@@ -64,12 +82,17 @@ std::string generate_uuid();
  * and converted to and from the text representation. */
 class ObjectReference {
 public:
+    enum RefType { REF_NULL, REF_ZERO, REF_NORMAL };
+
     ObjectReference();
+    ObjectReference(RefType t);
     ObjectReference(const std::string& segment, int sequence);
     ObjectReference(const std::string& segment, const std::string& sequence);
 
+    bool is_null() const { return type == REF_NULL; }
+    bool is_normal() const { return type == REF_NORMAL; }
     std::string to_string() const;
-    static ObjectReference *parse(const std::string& s);
+    static ObjectReference parse(const std::string& s);
 
     std::string get_segment() const { return segment; }
     std::string get_sequence() const { return object; }
@@ -88,7 +111,10 @@ public:
     void set_range(size_t start, size_t length)
         { range_start = start; range_length = length; range_valid = true; }
 
+    bool merge(ObjectReference ref);
+
 private:
+    RefType type;
     std::string segment, object, checksum;
     size_t range_start, range_length;
     bool checksum_valid, range_valid;