summaryrefslogtreecommitdiff
path: root/poppler/StructTreeRoot.cc
blob: 59f017ee9103691129b7dd1ddb329ada18de85e2 (plain)
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
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
//========================================================================
//
// StructTreeRoot.cc
//
// This file is licensed under the GPLv2 or later
//
// Copyright 2013 Igalia S.L.
//
//========================================================================

#ifdef USE_GCC_PRAGMAS
#pragma interface
#endif

#include "goo/GooString.h"
#include "StructTreeRoot.h"
#include "StructElement.h"
#include "PDFDoc.h"
#include "Object.h"
#include "Dict.h"
#include <set>
#include <assert.h>


StructTreeRoot::StructTreeRoot(PDFDoc *docA, Dict *structTreeRootDict):
  doc(docA)
{
  assert(doc);
  assert(structTreeRootDict);
  parse(structTreeRootDict);
}

StructTreeRoot::~StructTreeRoot()
{
  for (ElemPtrArray::iterator i = elements.begin(); i != elements.end(); ++i)
    delete *i;
  classMap.free();
  roleMap.free();
}

void StructTreeRoot::parse(Dict *root)
{
  // The RoleMap/ClassMap dictionaries are needed by all the parsing
  // functions, which will resolve the custom names to canonical
  // standard names.
  root->lookup("RoleMap", &roleMap);
  root->lookup("ClassMap", &classMap);

  // ParentTree (optional). If present, it must be a number tree,
  // otherwise it is not possible to map stream objects to their
  // corresponsing structure element. Here only the references are
  // loaded into the array, the pointers to the StructElements will
  // be filled-in later when parsing them.
  Object obj;
  if (root->lookup("ParentTree", &obj)->isDict()) {
    Object nums;
    if (obj.dictLookup("Nums", &nums)->isArray()) {
      if (nums.arrayGetLength() % 2 == 0) {
        parentTree.resize(nums.arrayGetLength() / 2);
        // Index numbers in even positions, references in odd ones
        for (int i = 0; i < nums.arrayGetLength(); i += 2) {
          Object index, value;

          if (!nums.arrayGet(i, &index)->isInt()) {
            error(errSyntaxError, -1, "Nums item at position {0:d} is wrong type ({1:s})", i, index.getTypeName());
            index.free();
            continue;
          }
          if (index.getInt() < 0) {
            error(errSyntaxError, -1, "Nums item at position {0:d} is invalid value ({1:d})", i, index.getInt());
            index.free();
            continue;
          }

          const unsigned idx = index.getInt();
          if (nums.arrayGetNF(i + 1, &value)->isRef()) {
            parentTree[idx].resize(1);
            parentTree[idx][0].ref = value.getRef();
          } else if (nums.arrayGet(i + 1, &value)->isArray()) {
            parentTree[idx].resize(value.arrayGetLength());
            for (int j = 0; j < value.arrayGetLength(); j++) {
              Object itemvalue;
              if (value.arrayGetNF(j, &itemvalue)->isRef())
                parentTree[idx][j].ref = itemvalue.getRef();
              else
                error(errSyntaxError, -1, "Nums array item at position {0:d}/{1:d} is invalid type ({2:s})", i, j, itemvalue.getTypeName());
              itemvalue.free();
            }
          } else {
            error(errSyntaxError, -1, "Nums item at position {0:d} is wrong type ({1:s})", i + 1, value.getTypeName());
          }

          value.free();
          index.free();
        }
      } else {
        error(errSyntaxError, -1, "Nums array length is not a even ({0:i})", nums.arrayGetLength());
      }
    } else {
      error(errSyntaxError, -1, "Nums object is wrong type ({0:s})", nums.getTypeName());
    }
    nums.free();
  }
  obj.free();

  std::set<int> seenElements;

  // Parse the children StructElements
  const GBool marked = doc->getCatalog()->getMarkInfo() & Catalog::markInfoMarked;
  Object kids;
  if (root->lookup("K", &kids)->isArray()) {
    if (marked && kids.arrayGetLength() > 1) {
      error(errSyntaxWarning, -1, "K in StructTreeRoot has more than one children in a tagged PDF");
    }
    for (int i = 0; i < kids.arrayGetLength(); i++) {
      Object obj, ref;
      kids.arrayGetNF(i, &ref);
      if (ref.isRef()) {
        seenElements.insert(ref.getRefNum());
      }
      if (kids.arrayGet(i, &obj)->isDict()) {
        StructElement *child = new StructElement(obj.getDict(), this, NULL, seenElements);
        if (child->isOk()) {
          if (marked && !(child->getType() == StructElement::Document ||
                          child->getType() == StructElement::Part ||
                          child->getType() == StructElement::Art ||
                          child->getType() == StructElement::Div)) {
            error(errSyntaxWarning, -1, "StructTreeRoot element of tagged PDF is wrong type ({0:s})", child->getTypeName());
          }
          appendElement(child);
          if (ref.isRef()) {
            parentTreeAdd(ref.getRef(), child);
          }
        } else {
          error(errSyntaxWarning, -1, "StructTreeRoot element could not be parsed");
          delete child;
        }
      } else {
        error(errSyntaxWarning, -1, "K has a child of wrong type ({0:s})", obj.getTypeName());
      }
      obj.free();
      ref.free();
    }
  } else if (kids.isDict()) {
    if (marked) {
      error(errSyntaxWarning, -1, "K has a child of wrong type for a tagged PDF ({0:s})", kids.getTypeName());
    }
    StructElement *child = new StructElement(kids.getDict(), this, NULL, seenElements);
    if (child->isOk()) {
      appendElement(child);
      Object ref;
      if (root->lookupNF("K", &ref)->isRef())
        parentTreeAdd(ref.getRef(), child);
      ref.free();
    } else {
      error(errSyntaxWarning, -1, "StructTreeRoot element could not be parsed");
      delete child;
    }
  } else if (!kids.isNull()) {
    error(errSyntaxWarning, -1, "K in StructTreeRoot is wrong type ({0:s})", kids.getTypeName());
  }

  kids.free();
}

void StructTreeRoot::parentTreeAdd(const Ref &objectRef, StructElement *element)
{
  for (std::vector< std::vector<Parent> >::iterator i = parentTree.begin(); i != parentTree.end(); ++i) {
    for (std::vector<Parent>::iterator j = i->begin(); j != i->end(); ++j) {
      if (j->ref.num == objectRef.num && j->ref.gen == objectRef.gen)
        j->element = element;
    }
  }
}