1/*
2 * Copyright 2011 Google Inc. All Rights Reserved.
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 SFNTLY_CPP_SRC_SFNTLY_DATA_FONT_DATA_H_
18#define SFNTLY_CPP_SRC_SFNTLY_DATA_FONT_DATA_H_
19
20#include <limits.h>
21
22#include <vector>
23
24#include "sfntly/port/type.h"
25#include "sfntly/data/byte_array.h"
26#include "sfntly/port/refcount.h"
27
28namespace sfntly {
29
30struct DataSize {
31  enum {
32    kBYTE = 1,
33    kCHAR = 1,
34    kUSHORT = 2,
35    kSHORT = 2,
36    kUINT24 = 3,
37    kULONG = 4,
38    kLONG = 4,
39    kFixed = 4,
40    kFUNIT = 4,
41    kFWORD = 2,
42    kUFWORD = 2,
43    kF2DOT14 = 2,
44    kLONGDATETIME = 8,
45    kTag = 4,
46    kGlyphID = 2,
47    kOffset = 2
48  };
49};
50
51class FontData : virtual public RefCount {
52 public:
53  // Gets the maximum size of the FontData. This is the maximum number of bytes
54  // that the font data can hold and all of it may not be filled with data or
55  // even fully allocated yet.
56  // @return the maximum size of this font data
57  virtual int32_t Size() const;
58
59  // Sets limits on the size of the FontData. The FontData is then only
60  // visible within the bounds set.
61  // @param offset the start of the new bounds
62  // @param length the number of bytes in the bounded array
63  // @return true if the bounding range was successful; false otherwise
64  virtual bool Bound(int32_t offset, int32_t length);
65
66  // Sets limits on the size of the FontData. This is a offset bound only so if
67  // the FontData is writable and growable then there is no limit to that growth
68  // from the bounding operation.
69  // @param offset the start of the new bounds which must be within the current
70  //        size of the FontData
71  // @return true if the bounding range was successful; false otherwise
72  virtual bool Bound(int32_t offset);
73
74  // Makes a slice of this FontData. The returned slice will share the data with
75  // the original <code>FontData</code>.
76  // @param offset the start of the slice
77  // @param length the number of bytes in the slice
78  // @return a slice of the original FontData
79  virtual CALLER_ATTACH FontData* Slice(int32_t offset, int32_t length) = 0;
80
81  // Makes a bottom bound only slice of this array. The returned slice will
82  // share the data with the original <code>FontData</code>.
83  // @param offset the start of the slice
84  // @return a slice of the original FontData
85  virtual CALLER_ATTACH FontData* Slice(int32_t offset) = 0;
86
87  // Gets the length of the data.
88  virtual int32_t Length() const;
89
90 protected:
91  // Constructor.
92  // @param ba the byte array to use for the backing data
93  explicit FontData(ByteArray* ba);
94
95  // Constructor.
96  // @param data the data to wrap
97  // @param offset the offset to start the wrap from
98  // @param length the length of the data wrapped
99  FontData(FontData* data, int32_t offset, int32_t length);
100
101  // Constructor.
102  // @param data the data to wrap
103  // @param offset the offset to start the wrap from
104  FontData(FontData* data, int32_t offset);
105  virtual ~FontData();
106
107  void Init(ByteArray* ba);
108
109  // Gets the offset in the underlying data taking into account any bounds on
110  // the data.
111  // @param offset the offset to get the bound compensated offset for
112  // @return the bound compensated offset
113  int32_t BoundOffset(int32_t offset);
114
115  // Gets the length in the underlying data taking into account any bounds on
116  // the data.
117  // @param offset the offset that the length is being used at
118  // @param length the length to get the bound compensated length for
119  // @return the bound compensated length
120  int32_t BoundLength(int32_t offset, int32_t length);
121
122  static const int32_t GROWABLE_SIZE = INT_MAX;
123
124  // TODO(arthurhsu): style guide violation: refactor this protected member
125  ByteArrayPtr array_;
126
127 private:
128  int32_t bound_offset_;
129  int32_t bound_length_;
130};
131typedef Ptr<FontData> FontDataPtr;
132
133}  // namespace sfntly
134
135#endif  // SFNTLY_CPP_SRC_SFNTLY_DATA_FONT_DATA_H_
136