1 // Copyright 2017 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 #include "core/fpdfapi/parser/cpdf_object_walker.h"
6
7 #include <sstream>
8 #include <string>
9 #include <utility>
10
11 #include "core/fpdfapi/parser/cpdf_array.h"
12 #include "core/fpdfapi/parser/cpdf_boolean.h"
13 #include "core/fpdfapi/parser/cpdf_dictionary.h"
14 #include "core/fpdfapi/parser/cpdf_name.h"
15 #include "core/fpdfapi/parser/cpdf_null.h"
16 #include "core/fpdfapi/parser/cpdf_number.h"
17 #include "core/fpdfapi/parser/cpdf_reference.h"
18 #include "core/fpdfapi/parser/cpdf_stream.h"
19 #include "core/fpdfapi/parser/cpdf_string.h"
20 #include "testing/gtest/include/gtest/gtest.h"
21 #include "third_party/base/ptr_util.h"
22
23 namespace {
24
Walk(CPDF_Object * object)25 std::string Walk(CPDF_Object* object) {
26 std::ostringstream result;
27 CPDF_ObjectWalker walker(object);
28 while (const CPDF_Object* obj = walker.GetNext()) {
29 if (obj->IsDictionary())
30 result << " Dict";
31 else if (obj->IsArray())
32 result << " Arr";
33 else if (obj->IsString())
34 result << " Str";
35 else if (obj->IsBoolean())
36 result << " Bool";
37 else if (obj->IsStream())
38 result << " Stream";
39 else if (obj->IsReference())
40 result << " Ref";
41 else if (obj->IsNumber())
42 result << " Num";
43 else if (obj->IsNull())
44 result << " Null";
45 else
46 result << " Unknown";
47 }
48 std::string result_str = result.str();
49 if (!result_str.empty()) {
50 result_str.erase(result_str.begin()); // remove start space
51 }
52 return result_str;
53 }
54
55 } // namespace
56
TEST(CPDF_ObjectWalkerTest,Simple)57 TEST(CPDF_ObjectWalkerTest, Simple) {
58 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Null>().Get()), "Null");
59 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Dictionary>().Get()), "Dict");
60 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Array>().Get()), "Arr");
61 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_String>().Get()), "Str");
62 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Boolean>().Get()), "Bool");
63 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Stream>().Get()), "Stream");
64 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Reference>(nullptr, 0).Get()), "Ref");
65 }
66
TEST(CPDF_ObjectWalkerTest,CombinedObject)67 TEST(CPDF_ObjectWalkerTest, CombinedObject) {
68 auto dict = pdfium::MakeRetain<CPDF_Dictionary>();
69 dict->SetFor("1", pdfium::MakeRetain<CPDF_String>());
70 dict->SetFor("2", pdfium::MakeRetain<CPDF_Boolean>());
71 auto array = pdfium::MakeRetain<CPDF_Array>();
72 array->Add(pdfium::MakeRetain<CPDF_Reference>(nullptr, 0));
73 array->Add(pdfium::MakeRetain<CPDF_Null>());
74 array->Add(pdfium::MakeRetain<CPDF_Stream>(
75 nullptr, 0, pdfium::MakeRetain<CPDF_Dictionary>()));
76 dict->SetFor("3", std::move(array));
77 // The last number for stream length.
78 EXPECT_EQ(Walk(dict.Get()), "Dict Str Bool Arr Ref Null Stream Dict Num");
79 }
80
TEST(CPDF_ObjectWalkerTest,GetParent)81 TEST(CPDF_ObjectWalkerTest, GetParent) {
82 auto level_4 = pdfium::MakeRetain<CPDF_Number>(0);
83 auto level_3 = pdfium::MakeRetain<CPDF_Dictionary>();
84 level_3->SetFor("Length", std::move(level_4));
85 auto level_2 =
86 pdfium::MakeRetain<CPDF_Stream>(nullptr, 0, std::move(level_3));
87 auto level_1 = pdfium::MakeRetain<CPDF_Array>();
88 level_1->Add(std::move(level_2));
89 auto level_0 = pdfium::MakeRetain<CPDF_Dictionary>();
90 level_0->SetFor("Array", std::move(level_1));
91
92 // We have <</Array [ stream( << /Length 0 >>) ]>>
93 // In this case each step will increase depth.
94 // And on each step the prev object should be parent for current.
95 const CPDF_Object* cur_parent = nullptr;
96 CPDF_ObjectWalker walker(level_0.Get());
97 while (const CPDF_Object* obj = walker.GetNext()) {
98 EXPECT_EQ(cur_parent, walker.GetParent());
99 cur_parent = obj;
100 }
101 }
102
TEST(CPDF_ObjectWalkerTest,SkipWalkIntoCurrentObject)103 TEST(CPDF_ObjectWalkerTest, SkipWalkIntoCurrentObject) {
104 auto root_array = pdfium::MakeRetain<CPDF_Array>();
105 // Add 2 null objects into |root_array|. [ null1, null2 ]
106 root_array->AddNew<CPDF_Null>();
107 root_array->AddNew<CPDF_Null>();
108 // |root_array| will contain 4 null objects after this.
109 // [ null1, null2, [ null3, null4 ] ]
110 root_array->Add(root_array->Clone());
111
112 int non_array_objects = 0;
113 CPDF_ObjectWalker walker(root_array.Get());
114 while (const CPDF_Object* obj = walker.GetNext()) {
115 if (obj != root_array && obj->IsArray()) {
116 // skip other array except root.
117 walker.SkipWalkIntoCurrentObject();
118 }
119 if (!obj->IsArray())
120 ++non_array_objects;
121 }
122 // 2 objects from child array should be skipped.
123 EXPECT_EQ(2, non_array_objects);
124 }
125
TEST(CPDF_ObjectWalkerTest,DictionaryKey)126 TEST(CPDF_ObjectWalkerTest, DictionaryKey) {
127 auto dict = pdfium::MakeRetain<CPDF_Dictionary>();
128 dict->SetFor("1", pdfium::MakeRetain<CPDF_Null>());
129 dict->SetFor("2", pdfium::MakeRetain<CPDF_Null>());
130 dict->SetFor("3", pdfium::MakeRetain<CPDF_Null>());
131 dict->SetFor("4", pdfium::MakeRetain<CPDF_Null>());
132 dict->SetFor("5", pdfium::MakeRetain<CPDF_Null>());
133
134 CPDF_ObjectWalker walker(dict.Get());
135 while (const CPDF_Object* obj = walker.GetNext()) {
136 if (dict == obj) {
137 // Ignore root dictinary object
138 continue;
139 }
140 // Test that, dictionary key is correct.
141 EXPECT_EQ(walker.GetParent()->AsDictionary()->GetObjectFor(
142 walker.dictionary_key()),
143 obj);
144 }
145 }
146