1 /*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "SkMatrixPriv.h"
9 #include "SkReader32.h"
10 #include "SkString.h"
11 #include "SkTo.h"
12
13 #include "SkWriter32.h"
14
writeMatrix(const SkMatrix & matrix)15 void SkWriter32::writeMatrix(const SkMatrix& matrix) {
16 size_t size = SkMatrixPriv::WriteToMemory(matrix, nullptr);
17 SkASSERT(SkAlign4(size) == size);
18 SkMatrixPriv::WriteToMemory(matrix, this->reserve(size));
19 }
20
21 /*
22 * Strings are stored as: length[4-bytes] + string_data + '\0' + pad_to_mul_4
23 */
24
readString(size_t * outLen)25 const char* SkReader32::readString(size_t* outLen) {
26 size_t len = this->readU32();
27 const void* ptr = this->peek();
28
29 // skip over the string + '\0' and then pad to a multiple of 4
30 size_t alignedSize = SkAlign4(len + 1);
31 this->skip(alignedSize);
32
33 if (outLen) {
34 *outLen = len;
35 }
36 return (const char*)ptr;
37 }
38
readIntoString(SkString * copy)39 size_t SkReader32::readIntoString(SkString* copy) {
40 size_t len;
41 const char* ptr = this->readString(&len);
42 if (copy) {
43 copy->set(ptr, len);
44 }
45 return len;
46 }
47
writeString(const char str[],size_t len)48 void SkWriter32::writeString(const char str[], size_t len) {
49 if (nullptr == str) {
50 str = "";
51 len = 0;
52 }
53 if ((long)len < 0) {
54 len = strlen(str);
55 }
56
57 // [ 4 byte len ] [ str ... ] [1 - 4 \0s]
58 uint32_t* ptr = this->reservePad(sizeof(uint32_t) + len + 1);
59 *ptr = SkToU32(len);
60 char* chars = (char*)(ptr + 1);
61 memcpy(chars, str, len);
62 chars[len] = '\0';
63 }
64
WriteStringSize(const char * str,size_t len)65 size_t SkWriter32::WriteStringSize(const char* str, size_t len) {
66 if ((long)len < 0) {
67 SkASSERT(str);
68 len = strlen(str);
69 }
70 const size_t lenBytes = 4; // we use 4 bytes to record the length
71 // add 1 since we also write a terminating 0
72 return SkAlign4(lenBytes + len + 1);
73 }
74
growToAtLeast(size_t size)75 void SkWriter32::growToAtLeast(size_t size) {
76 const bool wasExternal = (fExternal != nullptr) && (fData == fExternal);
77
78 fCapacity = 4096 + SkTMax(size, fCapacity + (fCapacity / 2));
79 fInternal.realloc(fCapacity);
80 fData = fInternal.get();
81
82 if (wasExternal) {
83 // we were external, so copy in the data
84 memcpy(fData, fExternal, fUsed);
85 }
86 }
87
snapshotAsData() const88 sk_sp<SkData> SkWriter32::snapshotAsData() const {
89 return SkData::MakeWithCopy(fData, fUsed);
90 }
91