1 // Copyright 2018 PDFium 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 CORE_FPDFAPI_PARSER_CPDF_OBJECT_STREAM_H_
6 #define CORE_FPDFAPI_PARSER_CPDF_OBJECT_STREAM_H_
7 
8 #include <map>
9 #include <memory>
10 
11 #include "core/fpdfapi/parser/cpdf_object.h"
12 #include "core/fxcrt/retain_ptr.h"
13 
14 class CPDF_IndirectObjectHolder;
15 class CPDF_Stream;
16 class IFX_SeekableReadStream;
17 
18 // Implementation of logic of PDF "Object Streams".
19 // See "PDF 32000-1:2008" Spec. section 7.5.7.
20 class CPDF_ObjectStream {
21  public:
22   static bool IsObjectsStreamObject(const CPDF_Object* object);
23 
24   static std::unique_ptr<CPDF_ObjectStream> Create(const CPDF_Stream* stream);
25 
26   ~CPDF_ObjectStream();
27 
obj_num()28   uint32_t obj_num() const { return obj_num_; }
extends_obj_num()29   uint32_t extends_obj_num() const { return extends_obj_num_; }
30 
31   bool HasObject(uint32_t obj_number) const;
32   RetainPtr<CPDF_Object> ParseObject(CPDF_IndirectObjectHolder* pObjList,
33                                      uint32_t obj_number) const;
objects_offsets()34   const std::map<uint32_t, uint32_t>& objects_offsets() const {
35     return objects_offsets_;
36   }
37 
38  protected:
39   explicit CPDF_ObjectStream(const CPDF_Stream* stream);
40 
41   void Init(const CPDF_Stream* stream);
42   RetainPtr<CPDF_Object> ParseObjectAtOffset(
43       CPDF_IndirectObjectHolder* pObjList,
44       uint32_t object_offset) const;
45 
46   uint32_t obj_num_ = CPDF_Object::kInvalidObjNum;
47   uint32_t extends_obj_num_ = CPDF_Object::kInvalidObjNum;
48 
49   RetainPtr<IFX_SeekableReadStream> data_stream_;
50   int first_object_offset_ = 0;
51   std::map<uint32_t, uint32_t> objects_offsets_;
52 };
53 
54 #endif  // CORE_FPDFAPI_PARSER_CPDF_OBJECT_STREAM_H_
55