sync/api/attachments/attachment_id.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef SYNC_API_ATTACHMENTS_ATTACHMENT_ID_H_
   6 #define SYNC_API_ATTACHMENTS_ATTACHMENT_ID_H_
   7
   8 #include <set>
   9 #include <string>
  10 #include <vector>
  11
  12 #include "sync/base/sync_export.h"
  13 #include "sync/internal_api/public/util/immutable.h"
  14
  15 namespace sync_pb {
  16 class AttachmentIdProto;
  17 }  // namespace sync_pb
  18
  19 namespace syncer {
  20
  21 // Uniquely identifies an attachment.
  22 //
  23 // Two attachments with equal (operator==) AttachmentIds are considered
  24 // equivalent.
  25 class SYNC_EXPORT AttachmentId {
  26  public:
  27   ~AttachmentId();
  28
  29   // Default copy and assignment are welcome.
  30
  31   bool operator==(const AttachmentId& other) const;
  32
  33   bool operator!=(const AttachmentId& other) const;
  34
  35   // Needed for using AttachmentId as key in std::map.
  36   bool operator<(const AttachmentId& other) const;
  37
  38   // Creates a unique id for an attachment.
  39   //
  40   // |size| is the attachment's size in bytes.
  41   //
  42   // |crc32c| is the attachment's crc32c.
  43   static AttachmentId Create(size_t size, uint32_t crc32c);
  44
  45   // Creates an attachment id from an initialized proto.
  46   static AttachmentId CreateFromProto(const sync_pb::AttachmentIdProto& proto);
  47
  48   const sync_pb::AttachmentIdProto& GetProto() const;
  49
  50   // Returns the size (in bytes) the attachment.
  51   size_t GetSize() const;
  52
  53   // Returns the crc32c the attachment.
  54   uint32_t GetCrc32c() const;
  55
  56  private:
  57   // Necessary since we forward-declare sync_pb::AttachmentIdProto; see comments
  58   // in immutable.h.
  59   struct SYNC_EXPORT ImmutableAttachmentIdProtoTraits {
  60     typedef sync_pb::AttachmentIdProto* Wrapper;
  61     static void InitializeWrapper(Wrapper* wrapper);
  62     static void DestroyWrapper(Wrapper* wrapper);
  63     static const sync_pb::AttachmentIdProto& Unwrap(const Wrapper& wrapper);
  64     static sync_pb::AttachmentIdProto* UnwrapMutable(Wrapper* wrapper);
  65     static void Swap(sync_pb::AttachmentIdProto* t1,
  66                      sync_pb::AttachmentIdProto* t2);
  67   };
  68
  69   typedef Immutable<sync_pb::AttachmentIdProto,
  70                     ImmutableAttachmentIdProtoTraits>
  71       ImmutableAttachmentIdProto;
  72
  73   ImmutableAttachmentIdProto proto_;
  74
  75   AttachmentId(sync_pb::AttachmentIdProto* proto);
  76 };
  77
  78 // All public interfaces use AttachmentIdList. AttachmentIdSet is used in
  79 // implementations of algorithms where set properties are needed.
  80 typedef std::vector<AttachmentId> AttachmentIdList;
  81 typedef std::set<AttachmentId> AttachmentIdSet;
  82
  83 }  // namespace syncer
  84
  85 #endif  // SYNC_API_ATTACHMENTS_ATTACHMENT_ID_H_