1 /*
2  * Copyright (C) 2013, The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef LATINIME_HEADER_READ_WRITE_UTILS_H
18 #define LATINIME_HEADER_READ_WRITE_UTILS_H
19 
20 #include <cstdint>
21 
22 #include "defines.h"
23 #include "dictionary/interface/dictionary_header_structure_policy.h"
24 #include "dictionary/utils/format_utils.h"
25 
26 namespace latinime {
27 
28 class BufferWithExtendableBuffer;
29 
30 class HeaderReadWriteUtils {
31  public:
32     typedef uint16_t DictionaryFlags;
33 
34     static int getHeaderSize(const uint8_t *const dictBuf);
35 
36     static DictionaryFlags getFlags(const uint8_t *const dictBuf);
37 
getHeaderOptionsPosition()38     static AK_FORCE_INLINE int getHeaderOptionsPosition() {
39         return HEADER_MAGIC_NUMBER_SIZE + HEADER_DICTIONARY_VERSION_SIZE + HEADER_FLAG_SIZE
40                 + HEADER_SIZE_FIELD_SIZE;
41     }
42 
43     static DictionaryFlags createAndGetDictionaryFlagsUsingAttributeMap(
44             const DictionaryHeaderStructurePolicy::AttributeMap *const attributeMap);
45 
46     static void fetchAllHeaderAttributes(const uint8_t *const dictBuf,
47             DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes);
48 
49     static const int *readCodePointTable(
50             DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes);
51 
52     static bool writeDictionaryVersion(BufferWithExtendableBuffer *const buffer,
53             const FormatUtils::FORMAT_VERSION version, int *const writingPos);
54 
55     static bool writeDictionaryFlags(BufferWithExtendableBuffer *const buffer,
56             const DictionaryFlags flags, int *const writingPos);
57 
58     static bool writeDictionaryHeaderSize(BufferWithExtendableBuffer *const buffer,
59             const int size, int *const writingPos);
60 
61     static bool writeHeaderAttributes(BufferWithExtendableBuffer *const buffer,
62             const DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
63             int *const writingPos);
64 
65     /**
66      * Methods for header attributes.
67      */
68     static void setCodePointVectorAttribute(
69             DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
70             const char *const key, const std::vector<int> &value);
71 
72     static void setBoolAttribute(
73             DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
74             const char *const key, const bool value);
75 
76     static void setIntAttribute(
77             DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
78             const char *const key, const int value);
79 
80     static const std::vector<int> readCodePointVectorAttributeValue(
81             const DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
82             const char *const key);
83 
84     static bool readBoolAttributeValue(
85             const DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
86             const char *const key, const bool defaultValue);
87 
88     static int readIntAttributeValue(
89             const DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
90             const char *const key, const int defaultValue);
91 
92     static void insertCharactersIntoVector(const char *const characters,
93             DictionaryHeaderStructurePolicy::AttributeMap::key_type *const key);
94 
95  private:
96     DISALLOW_IMPLICIT_CONSTRUCTORS(HeaderReadWriteUtils);
97 
98     static const int LARGEST_INT_DIGIT_COUNT;
99     static const int MAX_ATTRIBUTE_KEY_LENGTH;
100     static const int MAX_ATTRIBUTE_VALUE_LENGTH;
101 
102     static const int HEADER_MAGIC_NUMBER_SIZE;
103     static const int HEADER_DICTIONARY_VERSION_SIZE;
104     static const int HEADER_FLAG_SIZE;
105     static const int HEADER_SIZE_FIELD_SIZE;
106 
107     static const char *const CODE_POINT_TABLE_KEY;
108 
109     // Value for the "flags" field. It's unused at the moment.
110     static const DictionaryFlags NO_FLAGS;
111 
112     static void setIntAttributeInner(
113             DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
114             const DictionaryHeaderStructurePolicy::AttributeMap::key_type *const key,
115             const int value);
116 
117     static int readIntAttributeValueInner(
118             const DictionaryHeaderStructurePolicy::AttributeMap *const headerAttributes,
119             const DictionaryHeaderStructurePolicy::AttributeMap::key_type *const key,
120             const int defaultValue);
121 };
122 }
123 #endif /* LATINIME_HEADER_READ_WRITE_UTILS_H */
124