1
2/*
3 * Copyright 2011 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8#include "SkEndian.h"
9#include "SkSfntUtils.h"
10
11static uint16_t parse_be16(const uint8_t*& p) {
12    uint16_t value = (p[0] << 8) | p[1];
13    p += 2;
14    return value;
15}
16
17static uint32_t parse_be32(const uint8_t*& p) {
18    uint32_t value = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
19    p += 4;
20    return value;
21}
22
23static Sk64 parse_be64(const uint8_t*& p) {
24    Sk64 value;
25    value.fHi = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
26    value.fLo = (p[4] << 24) | (p[5] << 16) | (p[6] << 8) | p[7];
27    p += 8;
28    return value;
29}
30
31///////////////////////////////////////////////////////////////////////////////
32
33bool SkSfntUtils::ReadTable_head(SkFontID fontID, SkSfntTable_head* head) {
34    static const uint32_t gTag = SkSetFourByteTag('h', 'e', 'a', 'd');
35    static const size_t gSize = 54;
36
37    uint8_t storage[gSize];
38    size_t size = SkFontHost::GetTableData(fontID, gTag, 0, gSize, storage);
39    if (size != gSize) {
40        return false;
41    }
42
43    const uint8_t* p = storage;
44    head->fVersion = parse_be32(p);
45    head->fRevision = parse_be32(p);
46    head->fCheckSumAdjustment = parse_be32(p);
47    head->fMagicNumber = parse_be32(p);
48    head->fFlags = parse_be16(p);
49    head->fUnitsPerEm = parse_be16(p);
50    head->fDateCreated = parse_be64(p);
51    head->fDateModified = parse_be64(p);
52    head->fXMin = parse_be16(p);
53    head->fXMin = parse_be16(p);
54    head->fXMin = parse_be16(p);
55    head->fXMin = parse_be16(p);
56    head->fMacStyle = parse_be16(p);
57    head->fLowestPPEM = parse_be16(p);
58    head->fFontDirectionHint = parse_be16(p);
59    head->fIndexToLocFormat = parse_be16(p);
60    head->fGlyphDataFormat = parse_be16(p);
61    SkASSERT(p - storage == (long)size);
62    return true;
63}
64
65bool SkSfntUtils::ReadTable_maxp(SkFontID fontID, SkSfntTable_maxp* maxp) {
66    static const uint32_t gTag = SkSetFourByteTag('m', 'a', 'x', 'p');
67    static const size_t gSize = 32;
68
69    uint8_t storage[gSize];
70    size_t size = SkFontHost::GetTableData(fontID, gTag, 0, gSize, storage);
71    if (size != gSize) {
72        return false;
73    }
74
75    const uint8_t* p = storage;
76    maxp->fVersion = parse_be32(p);
77    maxp->fNumGlyphs = parse_be16(p);
78    maxp->fMaxPoints = parse_be16(p);
79    maxp->fMaxContours = parse_be16(p);
80    maxp->fMaxComponentPoints = parse_be16(p);
81    maxp->fMaxComponentContours = parse_be16(p);
82    maxp->fMaxZones = parse_be16(p);
83    maxp->fMaxTwilightPoints = parse_be16(p);
84    maxp->fMaxStorage = parse_be16(p);
85    maxp->fMaxFunctionDefs = parse_be16(p);
86    maxp->fMaxInstructionDefs = parse_be16(p);
87    maxp->fMaxStackElements = parse_be16(p);
88    maxp->fMaxSizeOfInstructions = parse_be16(p);
89    maxp->fMaxComponentElements = parse_be16(p);
90    maxp->fMaxComponentDepth = parse_be16(p);
91    SkASSERT(p - storage == (long)size);
92    return true;
93}
94
95