summaryrefslogtreecommitdiff
path: root/core/fpdfapi/page/cpdf_contentparser.cpp
blob: 3427fe52300c85c11f7acf20681618ff7d6920e0 (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
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
// Copyright 2016 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/fpdfapi/page/cpdf_contentparser.h"

#include "constants/page_object.h"
#include "core/fpdfapi/font/cpdf_type3char.h"
#include "core/fpdfapi/page/cpdf_allstates.h"
#include "core/fpdfapi/page/cpdf_form.h"
#include "core/fpdfapi/page/cpdf_page.h"
#include "core/fpdfapi/page/cpdf_pageobject.h"
#include "core/fpdfapi/page/cpdf_path.h"
#include "core/fpdfapi/parser/cpdf_array.h"
#include "core/fpdfapi/parser/cpdf_dictionary.h"
#include "core/fpdfapi/parser/cpdf_stream.h"
#include "core/fpdfapi/parser/cpdf_stream_acc.h"
#include "core/fxcrt/fx_safe_types.h"
#include "core/fxcrt/pauseindicator_iface.h"
#include "third_party/base/ptr_util.h"

#define PARSE_STEP_LIMIT 100

CPDF_ContentParser::CPDF_ContentParser(CPDF_Page* pPage)
    : m_CurrentStage(Stage::kGetContent), m_pObjectHolder(pPage) {
  ASSERT(pPage);
  if (!pPage->GetDocument() || !pPage->GetDict()) {
    m_CurrentStage = Stage::kComplete;
    return;
  }

  CPDF_Object* pContent =
      pPage->GetDict()->GetDirectObjectFor(pdfium::page_object::kContents);
  if (!pContent) {
    m_CurrentStage = Stage::kComplete;
    return;
  }

  CPDF_Stream* pStream = pContent->AsStream();
  if (pStream) {
    m_pSingleStream = pdfium::MakeRetain<CPDF_StreamAcc>(pStream);
    m_pSingleStream->LoadAllDataFiltered();
    m_CurrentStage = Stage::kPrepareContent;
    return;
  }

  CPDF_Array* pArray = pContent->AsArray();
  if (!pArray) {
    m_CurrentStage = Stage::kComplete;
    return;
  }

  m_nStreams = pArray->GetCount();
  if (m_nStreams == 0) {
    m_CurrentStage = Stage::kComplete;
    return;
  }
  m_StreamArray.resize(m_nStreams);
}

CPDF_ContentParser::CPDF_ContentParser(CPDF_Form* pForm,
                                       CPDF_AllStates* pGraphicStates,
                                       const CFX_Matrix* pParentMatrix,
                                       CPDF_Type3Char* pType3Char,
                                       std::set<const uint8_t*>* parsedSet)
    : m_CurrentStage(Stage::kParse),
      m_pObjectHolder(pForm),
      m_pType3Char(pType3Char) {
  ASSERT(pForm);
  CFX_Matrix form_matrix = pForm->GetDict()->GetMatrixFor("Matrix");
  if (pGraphicStates)
    form_matrix.Concat(pGraphicStates->m_CTM);

  CPDF_Array* pBBox = pForm->GetDict()->GetArrayFor("BBox");
  CFX_FloatRect form_bbox;
  CPDF_Path ClipPath;
  if (pBBox) {
    form_bbox = pBBox->GetRect();
    ClipPath.Emplace();
    ClipPath.AppendRect(form_bbox.left, form_bbox.bottom, form_bbox.right,
                        form_bbox.top);
    ClipPath.Transform(&form_matrix);
    if (pParentMatrix)
      ClipPath.Transform(pParentMatrix);

    form_bbox = form_matrix.TransformRect(form_bbox);
    if (pParentMatrix)
      form_bbox = pParentMatrix->TransformRect(form_bbox);
  }

  CPDF_Dictionary* pResources = pForm->GetDict()->GetDictFor("Resources");
  m_pParser = pdfium::MakeUnique<CPDF_StreamContentParser>(
      pForm->GetDocument(), pForm->m_pPageResources.Get(),
      pForm->m_pResources.Get(), pParentMatrix, pForm, pResources, form_bbox,
      pGraphicStates, parsedSet);
  m_pParser->GetCurStates()->m_CTM = form_matrix;
  m_pParser->GetCurStates()->m_ParentMatrix = form_matrix;
  if (ClipPath.HasRef()) {
    m_pParser->GetCurStates()->m_ClipPath.AppendPath(ClipPath, FXFILL_WINDING,
                                                     true);
  }
  if (pForm->GetTransparency().IsGroup()) {
    CPDF_GeneralState* pState = &m_pParser->GetCurStates()->m_GeneralState;
    pState->SetBlendType(FXDIB_BLEND_NORMAL);
    pState->SetStrokeAlpha(1.0f);
    pState->SetFillAlpha(1.0f);
    pState->SetSoftMask(nullptr);
  }
  m_pSingleStream = pdfium::MakeRetain<CPDF_StreamAcc>(pForm->GetStream());
  m_pSingleStream->LoadAllDataFiltered();
  m_pData.Reset(m_pSingleStream->GetData());
  m_Size = m_pSingleStream->GetSize();
}

CPDF_ContentParser::~CPDF_ContentParser() {}

// Returning |true| means that there is more content to be processed and
// Continue() should be called again. Returning |false| means that we've
// completed the parse and Continue() is complete.
bool CPDF_ContentParser::Continue(PauseIndicatorIface* pPause) {
  while (m_CurrentStage == Stage::kGetContent) {
    m_CurrentStage = GetContent();
    if (pPause && pPause->NeedToPauseNow())
      return true;
  }

  if (m_CurrentStage == Stage::kPrepareContent)
    m_CurrentStage = PrepareContent();

  while (m_CurrentStage == Stage::kParse) {
    m_CurrentStage = Parse();
    if (pPause && pPause->NeedToPauseNow())
      return true;
  }

  if (m_CurrentStage == Stage::kCheckClip)
    m_CurrentStage = CheckClip();

  ASSERT(m_CurrentStage == Stage::kComplete);
  return false;
}

CPDF_ContentParser::Stage CPDF_ContentParser::GetContent() {
  ASSERT(m_CurrentStage == Stage::kGetContent);
  ASSERT(m_pObjectHolder->IsPage());
  CPDF_Array* pContent =
      m_pObjectHolder->GetDict()->GetArrayFor(pdfium::page_object::kContents);
  CPDF_Stream* pStreamObj = ToStream(
      pContent ? pContent->GetDirectObjectAt(m_CurrentOffset) : nullptr);
  m_StreamArray[m_CurrentOffset] =
      pdfium::MakeRetain<CPDF_StreamAcc>(pStreamObj);
  m_StreamArray[m_CurrentOffset]->LoadAllDataFiltered();
  m_CurrentOffset++;

  return m_CurrentOffset == m_nStreams ? Stage::kPrepareContent
                                       : Stage::kGetContent;
}

CPDF_ContentParser::Stage CPDF_ContentParser::PrepareContent() {
  m_CurrentOffset = 0;

  if (m_StreamArray.empty()) {
    m_pData.Reset(m_pSingleStream->GetData());
    m_Size = m_pSingleStream->GetSize();
    return Stage::kParse;
  }

  FX_SAFE_UINT32 safeSize = 0;
  for (const auto& stream : m_StreamArray) {
    m_StreamSegmentOffsets.push_back(safeSize.ValueOrDie());

    safeSize += stream->GetSize();
    safeSize += 1;
    if (!safeSize.IsValid())
      return Stage::kComplete;
  }

  m_Size = safeSize.ValueOrDie();
  m_pData.Reset(
      std::unique_ptr<uint8_t, FxFreeDeleter>(FX_Alloc(uint8_t, m_Size)));

  uint32_t pos = 0;
  for (const auto& stream : m_StreamArray) {
    memcpy(m_pData.Get() + pos, stream->GetData(), stream->GetSize());
    pos += stream->GetSize();
    m_pData.Get()[pos++] = ' ';
  }
  m_StreamArray.clear();

  return Stage::kParse;
}

CPDF_ContentParser::Stage CPDF_ContentParser::Parse() {
  if (!m_pParser) {
    m_parsedSet = pdfium::MakeUnique<std::set<const uint8_t*>>();
    m_pParser = pdfium::MakeUnique<CPDF_StreamContentParser>(
        m_pObjectHolder->GetDocument(), m_pObjectHolder->m_pPageResources.Get(),
        nullptr, nullptr, m_pObjectHolder.Get(),
        m_pObjectHolder->m_pResources.Get(), m_pObjectHolder->GetBBox(),
        nullptr, m_parsedSet.get());
    m_pParser->GetCurStates()->m_ColorState.SetDefault();
  }
  if (m_CurrentOffset >= m_Size)
    return Stage::kCheckClip;

  if (m_StreamSegmentOffsets.empty())
    m_StreamSegmentOffsets.push_back(0);

  m_CurrentOffset += m_pParser->Parse(m_pData.Get(), m_Size, m_CurrentOffset,
                                      PARSE_STEP_LIMIT, m_StreamSegmentOffsets);
  return Stage::kParse;
}

CPDF_ContentParser::Stage CPDF_ContentParser::CheckClip() {
  if (m_pType3Char) {
    m_pType3Char->InitializeFromStreamData(m_pParser->IsColored(),
                                           m_pParser->GetType3Data());
  }

  for (auto& pObj : *m_pObjectHolder->GetPageObjectList()) {
    if (!pObj->m_ClipPath.HasRef())
      continue;
    if (pObj->m_ClipPath.GetPathCount() != 1)
      continue;
    if (pObj->m_ClipPath.GetTextCount() > 0)
      continue;

    CPDF_Path ClipPath = pObj->m_ClipPath.GetPath(0);
    if (!ClipPath.IsRect() || pObj->IsShading())
      continue;

    CFX_PointF point0 = ClipPath.GetPoint(0);
    CFX_PointF point2 = ClipPath.GetPoint(2);
    CFX_FloatRect old_rect(point0.x, point0.y, point2.x, point2.y);
    if (old_rect.Contains(pObj->GetRect()))
      pObj->m_ClipPath.SetNull();
  }
  return Stage::kComplete;
}