1 // Copyright 2016 PDFium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6
7 #include "core/fpdfdoc/cpdf_occontext.h"
8
9 #include "core/fpdfapi/page/cpdf_pageobject.h"
10 #include "core/fpdfapi/parser/cpdf_array.h"
11 #include "core/fpdfapi/parser/cpdf_document.h"
12
13 namespace {
14
FindGroup(const CPDF_Array * pArray,const CPDF_Dictionary * pGroupDict)15 int32_t FindGroup(const CPDF_Array* pArray, const CPDF_Dictionary* pGroupDict) {
16 if (!pArray || !pGroupDict)
17 return -1;
18
19 for (size_t i = 0; i < pArray->GetCount(); i++) {
20 if (pArray->GetDictAt(i) == pGroupDict)
21 return i;
22 }
23 return -1;
24 }
25
HasIntent(const CPDF_Dictionary * pDict,const ByteStringView & csElement,const ByteStringView & csDef)26 bool HasIntent(const CPDF_Dictionary* pDict,
27 const ByteStringView& csElement,
28 const ByteStringView& csDef) {
29 CPDF_Object* pIntent = pDict->GetDirectObjectFor("Intent");
30 if (!pIntent)
31 return csElement == csDef;
32
33 ByteString bsIntent;
34 if (CPDF_Array* pArray = pIntent->AsArray()) {
35 for (size_t i = 0; i < pArray->GetCount(); i++) {
36 bsIntent = pArray->GetStringAt(i);
37 if (bsIntent == "All" || bsIntent == csElement)
38 return true;
39 }
40 return false;
41 }
42 bsIntent = pIntent->GetString();
43 return bsIntent == "All" || bsIntent == csElement;
44 }
45
GetConfig(CPDF_Document * pDoc,const CPDF_Dictionary * pOCGDict)46 CPDF_Dictionary* GetConfig(CPDF_Document* pDoc,
47 const CPDF_Dictionary* pOCGDict) {
48 ASSERT(pOCGDict);
49 CPDF_Dictionary* pOCProperties = pDoc->GetRoot()->GetDictFor("OCProperties");
50 if (!pOCProperties)
51 return nullptr;
52
53 CPDF_Array* pOCGs = pOCProperties->GetArrayFor("OCGs");
54 if (!pOCGs)
55 return nullptr;
56
57 if (FindGroup(pOCGs, pOCGDict) < 0)
58 return nullptr;
59
60 CPDF_Dictionary* pConfig = pOCProperties->GetDictFor("D");
61 CPDF_Array* pConfigs = pOCProperties->GetArrayFor("Configs");
62 if (!pConfigs)
63 return pConfig;
64
65 for (size_t i = 0; i < pConfigs->GetCount(); i++) {
66 CPDF_Dictionary* pFind = pConfigs->GetDictAt(i);
67 if (pFind && HasIntent(pFind, "View", "View"))
68 return pFind;
69 }
70 return pConfig;
71 }
72
GetUsageTypeString(CPDF_OCContext::UsageType eType)73 ByteString GetUsageTypeString(CPDF_OCContext::UsageType eType) {
74 ByteString csState;
75 switch (eType) {
76 case CPDF_OCContext::Design:
77 csState = "Design";
78 break;
79 case CPDF_OCContext::Print:
80 csState = "Print";
81 break;
82 case CPDF_OCContext::Export:
83 csState = "Export";
84 break;
85 default:
86 csState = "View";
87 break;
88 }
89 return csState;
90 }
91
92 } // namespace
93
CPDF_OCContext(CPDF_Document * pDoc,UsageType eUsageType)94 CPDF_OCContext::CPDF_OCContext(CPDF_Document* pDoc, UsageType eUsageType)
95 : m_pDocument(pDoc), m_eUsageType(eUsageType) {
96 ASSERT(pDoc);
97 }
98
~CPDF_OCContext()99 CPDF_OCContext::~CPDF_OCContext() {}
100
LoadOCGStateFromConfig(const ByteString & csConfig,const CPDF_Dictionary * pOCGDict) const101 bool CPDF_OCContext::LoadOCGStateFromConfig(
102 const ByteString& csConfig,
103 const CPDF_Dictionary* pOCGDict) const {
104 CPDF_Dictionary* pConfig = GetConfig(m_pDocument.Get(), pOCGDict);
105 if (!pConfig)
106 return true;
107
108 bool bState = pConfig->GetStringFor("BaseState", "ON") != "OFF";
109 CPDF_Array* pArray = pConfig->GetArrayFor("ON");
110 if (pArray) {
111 if (FindGroup(pArray, pOCGDict) >= 0)
112 bState = true;
113 }
114 pArray = pConfig->GetArrayFor("OFF");
115 if (pArray) {
116 if (FindGroup(pArray, pOCGDict) >= 0)
117 bState = false;
118 }
119 pArray = pConfig->GetArrayFor("AS");
120 if (!pArray)
121 return bState;
122
123 ByteString csFind = csConfig + "State";
124 for (size_t i = 0; i < pArray->GetCount(); i++) {
125 CPDF_Dictionary* pUsage = pArray->GetDictAt(i);
126 if (!pUsage)
127 continue;
128
129 if (pUsage->GetStringFor("Event", "View") != csConfig)
130 continue;
131
132 CPDF_Array* pOCGs = pUsage->GetArrayFor("OCGs");
133 if (!pOCGs)
134 continue;
135
136 if (FindGroup(pOCGs, pOCGDict) < 0)
137 continue;
138
139 CPDF_Dictionary* pState = pUsage->GetDictFor(csConfig);
140 if (!pState)
141 continue;
142
143 bState = pState->GetStringFor(csFind) != "OFF";
144 }
145 return bState;
146 }
147
LoadOCGState(const CPDF_Dictionary * pOCGDict) const148 bool CPDF_OCContext::LoadOCGState(const CPDF_Dictionary* pOCGDict) const {
149 if (!HasIntent(pOCGDict, "View", "View"))
150 return true;
151
152 ByteString csState = GetUsageTypeString(m_eUsageType);
153 CPDF_Dictionary* pUsage = pOCGDict->GetDictFor("Usage");
154 if (pUsage) {
155 CPDF_Dictionary* pState = pUsage->GetDictFor(csState);
156 if (pState) {
157 ByteString csFind = csState + "State";
158 if (pState->KeyExist(csFind))
159 return pState->GetStringFor(csFind) != "OFF";
160 }
161 if (csState != "View") {
162 pState = pUsage->GetDictFor("View");
163 if (pState && pState->KeyExist("ViewState"))
164 return pState->GetStringFor("ViewState") != "OFF";
165 }
166 }
167 return LoadOCGStateFromConfig(csState, pOCGDict);
168 }
169
GetOCGVisible(const CPDF_Dictionary * pOCGDict)170 bool CPDF_OCContext::GetOCGVisible(const CPDF_Dictionary* pOCGDict) {
171 if (!pOCGDict)
172 return false;
173
174 const auto it = m_OCGStates.find(pOCGDict);
175 if (it != m_OCGStates.end())
176 return it->second;
177
178 bool bState = LoadOCGState(pOCGDict);
179 m_OCGStates[pOCGDict] = bState;
180 return bState;
181 }
182
CheckObjectVisible(const CPDF_PageObject * pObj)183 bool CPDF_OCContext::CheckObjectVisible(const CPDF_PageObject* pObj) {
184 for (size_t i = 0; i < pObj->m_ContentMark.CountItems(); ++i) {
185 const CPDF_ContentMarkItem& item = pObj->m_ContentMark.GetItem(i);
186 if (item.GetName() == "OC" &&
187 item.GetParamType() == CPDF_ContentMarkItem::PropertiesDict &&
188 !CheckOCGVisible(item.GetParam())) {
189 return false;
190 }
191 }
192 return true;
193 }
194
GetOCGVE(CPDF_Array * pExpression,int nLevel)195 bool CPDF_OCContext::GetOCGVE(CPDF_Array* pExpression, int nLevel) {
196 if (nLevel > 32 || !pExpression)
197 return false;
198
199 ByteString csOperator = pExpression->GetStringAt(0);
200 if (csOperator == "Not") {
201 CPDF_Object* pOCGObj = pExpression->GetDirectObjectAt(1);
202 if (!pOCGObj)
203 return false;
204 if (CPDF_Dictionary* pDict = pOCGObj->AsDictionary())
205 return !GetOCGVisible(pDict);
206 if (CPDF_Array* pArray = pOCGObj->AsArray())
207 return !GetOCGVE(pArray, nLevel + 1);
208 return false;
209 }
210
211 if (csOperator != "Or" && csOperator != "And")
212 return false;
213
214 bool bValue = false;
215 for (size_t i = 1; i < pExpression->GetCount(); i++) {
216 CPDF_Object* pOCGObj = pExpression->GetDirectObjectAt(1);
217 if (!pOCGObj)
218 continue;
219
220 bool bItem = false;
221 if (CPDF_Dictionary* pDict = pOCGObj->AsDictionary())
222 bItem = GetOCGVisible(pDict);
223 else if (CPDF_Array* pArray = pOCGObj->AsArray())
224 bItem = GetOCGVE(pArray, nLevel + 1);
225
226 if (i == 1) {
227 bValue = bItem;
228 } else {
229 if (csOperator == "Or") {
230 bValue = bValue || bItem;
231 } else {
232 bValue = bValue && bItem;
233 }
234 }
235 }
236 return bValue;
237 }
238
LoadOCMDState(const CPDF_Dictionary * pOCMDDict)239 bool CPDF_OCContext::LoadOCMDState(const CPDF_Dictionary* pOCMDDict) {
240 CPDF_Array* pVE = pOCMDDict->GetArrayFor("VE");
241 if (pVE)
242 return GetOCGVE(pVE, 0);
243
244 ByteString csP = pOCMDDict->GetStringFor("P", "AnyOn");
245 CPDF_Object* pOCGObj = pOCMDDict->GetDirectObjectFor("OCGs");
246 if (!pOCGObj)
247 return true;
248
249 if (const CPDF_Dictionary* pDict = pOCGObj->AsDictionary())
250 return GetOCGVisible(pDict);
251
252 CPDF_Array* pArray = pOCGObj->AsArray();
253 if (!pArray)
254 return true;
255
256 bool bState = (csP == "AllOn" || csP == "AllOff");
257 // At least one entry of OCGs needs to be a valid dictionary for it to be
258 // considered present. See "OCGs" in table 4.49 in the PDF 1.7 spec.
259 bool bValidEntrySeen = false;
260 for (size_t i = 0; i < pArray->GetCount(); i++) {
261 bool bItem = true;
262 CPDF_Dictionary* pItemDict = pArray->GetDictAt(i);
263 if (!pItemDict)
264 continue;
265
266 bValidEntrySeen = true;
267 bItem = GetOCGVisible(pItemDict);
268
269 if ((csP == "AnyOn" && bItem) || (csP == "AnyOff" && !bItem))
270 return true;
271 if ((csP == "AllOn" && !bItem) || (csP == "AllOff" && bItem))
272 return false;
273 }
274
275 return !bValidEntrySeen || bState;
276 }
277
CheckOCGVisible(const CPDF_Dictionary * pOCGDict)278 bool CPDF_OCContext::CheckOCGVisible(const CPDF_Dictionary* pOCGDict) {
279 if (!pOCGDict)
280 return true;
281
282 ByteString csType = pOCGDict->GetStringFor("Type", "OCG");
283 if (csType == "OCG")
284 return GetOCGVisible(pOCGDict);
285 return LoadOCMDState(pOCGDict);
286 }
287