1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
// Copyright 2017 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
#include "core/fpdfdoc/cpdf_structtree.h"
#include "core/fpdfapi/parser/cpdf_array.h"
#include "core/fpdfapi/parser/cpdf_document.h"
#include "core/fpdfapi/parser/cpdf_number.h"
#include "core/fpdfapi/parser/cpdf_reference.h"
#include "core/fpdfdoc/cpdf_numbertree.h"
#include "core/fpdfdoc/cpdf_structelement.h"
namespace {
bool IsTagged(const CPDF_Document* pDoc) {
const CPDF_Dictionary* pCatalog = pDoc->GetRoot();
const CPDF_Dictionary* pMarkInfo = pCatalog->GetDictFor("MarkInfo");
return pMarkInfo && pMarkInfo->GetIntegerFor("Marked");
}
} // namespace
// static
std::unique_ptr<CPDF_StructTree> CPDF_StructTree::LoadPage(
const CPDF_Document* pDoc,
const CPDF_Dictionary* pPageDict) {
if (!IsTagged(pDoc))
return nullptr;
auto pTree = pdfium::MakeUnique<CPDF_StructTree>(pDoc);
pTree->LoadPageTree(pPageDict);
return pTree;
}
CPDF_StructTree::CPDF_StructTree(const CPDF_Document* pDoc)
: m_pTreeRoot(pDoc->GetRoot()->GetDictFor("StructTreeRoot")),
m_pRoleMap(m_pTreeRoot ? m_pTreeRoot->GetDictFor("RoleMap") : nullptr),
m_pPage(nullptr) {}
CPDF_StructTree::~CPDF_StructTree() {}
void CPDF_StructTree::LoadPageTree(const CPDF_Dictionary* pPageDict) {
m_pPage = pPageDict;
if (!m_pTreeRoot)
return;
CPDF_Object* pKids = m_pTreeRoot->GetDirectObjectFor("K");
if (!pKids)
return;
uint32_t dwKids = 0;
if (pKids->IsDictionary())
dwKids = 1;
else if (CPDF_Array* pArray = pKids->AsArray())
dwKids = pArray->GetCount();
else
return;
m_Kids.clear();
m_Kids.resize(dwKids);
const CPDF_Dictionary* pParentTree = m_pTreeRoot->GetDictFor("ParentTree");
if (!pParentTree)
return;
CPDF_NumberTree parent_tree(pParentTree);
int parents_id = pPageDict->GetIntegerFor("StructParents", -1);
if (parents_id < 0)
return;
const CPDF_Array* pParentArray = ToArray(parent_tree.LookupValue(parents_id));
if (!pParentArray)
return;
StructElementMap element_map;
for (size_t i = 0; i < pParentArray->GetCount(); i++) {
if (const CPDF_Dictionary* pParent = pParentArray->GetDictAt(i))
AddPageNode(pParent, &element_map, 0);
}
}
RetainPtr<CPDF_StructElement> CPDF_StructTree::AddPageNode(
const CPDF_Dictionary* pDict,
StructElementMap* map,
int nLevel) {
static constexpr int kStructTreeMaxRecursion = 32;
if (nLevel > kStructTreeMaxRecursion)
return nullptr;
auto it = map->find(pDict);
if (it != map->end())
return it->second;
auto pElement = pdfium::MakeRetain<CPDF_StructElement>(this, nullptr, pDict);
(*map)[pDict] = pElement;
const CPDF_Dictionary* pParent = pDict->GetDictFor("P");
if (!pParent || pParent->GetStringFor("Type") == "StructTreeRoot") {
if (!AddTopLevelNode(pDict, pElement))
map->erase(pDict);
return pElement;
}
RetainPtr<CPDF_StructElement> pParentElement =
AddPageNode(pParent, map, nLevel + 1);
bool bSave = false;
for (CPDF_StructKid& kid : *pParentElement->GetKids()) {
if (kid.m_Type == CPDF_StructKid::Element && kid.m_pDict == pDict) {
kid.m_pElement = pElement;
bSave = true;
}
}
if (!bSave)
map->erase(pDict);
return pElement;
}
bool CPDF_StructTree::AddTopLevelNode(
const CPDF_Dictionary* pDict,
const RetainPtr<CPDF_StructElement>& pElement) {
CPDF_Object* pObj = m_pTreeRoot->GetDirectObjectFor("K");
if (!pObj)
return false;
if (pObj->IsDictionary()) {
if (pObj->GetObjNum() != pDict->GetObjNum())
return false;
m_Kids[0] = pElement;
}
CPDF_Array* pTopKids = pObj->AsArray();
if (!pTopKids)
return true;
bool bSave = false;
for (size_t i = 0; i < pTopKids->GetCount(); i++) {
CPDF_Reference* pKidRef = ToReference(pTopKids->GetObjectAt(i));
if (pKidRef && pKidRef->GetRefObjNum() == pDict->GetObjNum()) {
m_Kids[i] = pElement;
bSave = true;
}
}
return bSave;
}
|
