| // Copyright 2018 The PDFium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef CORE_FPDFAPI_PARSER_CPDF_CROSS_REF_TABLE_H_ |
| #define CORE_FPDFAPI_PARSER_CPDF_CROSS_REF_TABLE_H_ |
| |
| #include <stdint.h> |
| |
| #include <map> |
| #include <memory> |
| |
| #include "core/fxcrt/fx_types.h" |
| #include "core/fxcrt/retain_ptr.h" |
| |
| class CPDF_Dictionary; |
| |
| class CPDF_CrossRefTable { |
| public: |
| enum class ObjectType : uint8_t { |
| kFree = 0x00, |
| kNormal = 0x01, |
| kCompressed = 0x02, |
| kObjStream = 0xFF, |
| kNull = kObjStream, |
| }; |
| |
| struct ObjectInfo { |
| ObjectInfo() = default; |
| |
| // If `type` is `ObjectType::kCompressed`, `archive` should be used. |
| // If `type` is `ObjectType::kNormal`, `pos` should be used. |
| // In other cases, it is unused. |
| union { |
| FX_FILESIZE pos = 0; |
| struct { |
| uint32_t obj_num; |
| uint32_t obj_index; |
| } archive; |
| }; |
| ObjectType type = ObjectType::kFree; |
| uint16_t gennum = 0; |
| }; |
| |
| // Merge cross reference tables. Apply top on current. |
| static std::unique_ptr<CPDF_CrossRefTable> MergeUp( |
| std::unique_ptr<CPDF_CrossRefTable> current, |
| std::unique_ptr<CPDF_CrossRefTable> top); |
| |
| CPDF_CrossRefTable(); |
| CPDF_CrossRefTable(RetainPtr<CPDF_Dictionary> trailer, |
| uint32_t trailer_object_number); |
| ~CPDF_CrossRefTable(); |
| |
| void AddCompressed(uint32_t obj_num, |
| uint32_t archive_obj_num, |
| uint32_t archive_obj_index); |
| void AddNormal(uint32_t obj_num, uint16_t gen_num, FX_FILESIZE pos); |
| void SetFree(uint32_t obj_num); |
| |
| void SetTrailer(RetainPtr<CPDF_Dictionary> trailer, |
| uint32_t trailer_object_number); |
| uint32_t trailer_object_number() const { return trailer_object_number_; } |
| const CPDF_Dictionary* trailer() const { return trailer_.Get(); } |
| CPDF_Dictionary* GetMutableTrailerForTesting() { return trailer_.Get(); } |
| |
| const ObjectInfo* GetObjectInfo(uint32_t obj_num) const; |
| |
| const std::map<uint32_t, ObjectInfo>& objects_info() const { |
| return objects_info_; |
| } |
| |
| void Update(std::unique_ptr<CPDF_CrossRefTable> new_cross_ref); |
| |
| // Objects with object number >= `size` will be removed. |
| void SetObjectMapSize(uint32_t size); |
| |
| private: |
| void UpdateInfo(std::map<uint32_t, ObjectInfo> new_objects_info); |
| void UpdateTrailer(RetainPtr<CPDF_Dictionary> new_trailer); |
| |
| RetainPtr<CPDF_Dictionary> trailer_; |
| // `trailer_` can be the dictionary part of a XRef stream object. Since it is |
| // inline, it has no object number. Store the stream's object number, or 0 if |
| // there is none. |
| uint32_t trailer_object_number_ = 0; |
| std::map<uint32_t, ObjectInfo> objects_info_; |
| }; |
| |
| #endif // CORE_FPDFAPI_PARSER_CPDF_CROSS_REF_TABLE_H_ |