xref: /aosp_15_r20/external/pdfium/core/fpdfapi/parser/cpdf_object_stream.h (revision 3ac0a46f773bac49fa9476ec2b1cf3f8da5ec3a4)
1 // Copyright 2018 The PDFium Authors
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 <memory>
9 #include <vector>
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 CPDF_StreamAcc;
17 class IFX_SeekableReadStream;
18 
19 // Implementation of logic of PDF "Object Streams".
20 // See ISO 32000-1:2008 spec, section 7.5.7.
21 class CPDF_ObjectStream {
22  public:
23   struct ObjectInfo {
ObjectInfoObjectInfo24     ObjectInfo(uint32_t obj_num, uint32_t obj_offset)
25         : obj_num(obj_num), obj_offset(obj_offset) {}
26 
27     bool operator==(const ObjectInfo& that) const {
28       return obj_num == that.obj_num && obj_offset == that.obj_offset;
29     }
30 
31     uint32_t obj_num;
32     uint32_t obj_offset;
33   };
34 
35   static std::unique_ptr<CPDF_ObjectStream> Create(
36       RetainPtr<const CPDF_Stream> stream);
37 
38   ~CPDF_ObjectStream();
39 
40   RetainPtr<CPDF_Object> ParseObject(CPDF_IndirectObjectHolder* pObjList,
41                                      uint32_t obj_number,
42                                      uint32_t archive_obj_index) const;
object_info()43   const std::vector<ObjectInfo>& object_info() const { return object_info_; }
44 
45  private:
46   explicit CPDF_ObjectStream(RetainPtr<const CPDF_Stream> stream);
47 
48   void Init(const CPDF_Stream* stream);
49   RetainPtr<CPDF_Object> ParseObjectAtOffset(
50       CPDF_IndirectObjectHolder* pObjList,
51       uint32_t object_offset) const;
52 
53   // Must outlive `data_stream_`.
54   RetainPtr<CPDF_StreamAcc> const stream_acc_;
55   RetainPtr<IFX_SeekableReadStream> data_stream_;
56   int first_object_offset_ = 0;
57   std::vector<ObjectInfo> object_info_;
58 };
59 
60 #endif  // CORE_FPDFAPI_PARSER_CPDF_OBJECT_STREAM_H_
61