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 #include <stdlib.h>
18 #include <stdint.h>
19 
20 #include <minikin/AnalyzeStyle.h>
21 
22 namespace android {
23 
24 // should  we have a single FontAnalyzer class this stuff lives in, to avoid dup?
readU16(const uint8_t * data,size_t offset)25 static int32_t readU16(const uint8_t* data, size_t offset) {
26     return data[offset] << 8 | data[offset + 1];
27 }
28 
analyzeStyle(const uint8_t * os2_data,size_t os2_size,int * weight,bool * italic)29 bool analyzeStyle(const uint8_t* os2_data, size_t os2_size, int* weight, bool* italic) {
30     const size_t kUsWeightClassOffset = 4;
31     const size_t kFsSelectionOffset = 62;
32     const uint16_t kItalicFlag = (1 << 0);
33     if (os2_size < kFsSelectionOffset + 2) {
34         return false;
35     }
36     uint16_t weightClass = readU16(os2_data, kUsWeightClassOffset);
37     *weight = weightClass / 100;
38     uint16_t fsSelection = readU16(os2_data, kFsSelectionOffset);
39     *italic = (fsSelection & kItalicFlag) != 0;
40     return true;
41 }
42 
43 }  // namespace android
44