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 "include/core/SkMallocPixelRef.h"
9
10 #include "include/core/SkData.h"
11 #include "include/core/SkImageInfo.h"
12 #include "include/private/base/SkMalloc.h"
13
is_valid(const SkImageInfo & info)14 static bool is_valid(const SkImageInfo& info) {
15 if (info.width() < 0 || info.height() < 0 ||
16 (unsigned)info.colorType() > (unsigned)kLastEnum_SkColorType ||
17 (unsigned)info.alphaType() > (unsigned)kLastEnum_SkAlphaType)
18 {
19 return false;
20 }
21 return true;
22 }
23
MakeAllocate(const SkImageInfo & info,size_t rowBytes)24 sk_sp<SkPixelRef> SkMallocPixelRef::MakeAllocate(const SkImageInfo& info, size_t rowBytes) {
25 if (rowBytes == 0) {
26 rowBytes = info.minRowBytes();
27 // rowBytes can still be zero, if it overflowed (width * bytesPerPixel > size_t)
28 // or if colortype is unknown
29 }
30 if (!is_valid(info) || !info.validRowBytes(rowBytes)) {
31 return nullptr;
32 }
33 size_t size = info.computeByteSize(rowBytes);
34 if (SkImageInfo::ByteSizeOverflowed(size)) {
35 return nullptr;
36 }
37 #if defined(SK_BUILD_FOR_FUZZER)
38 if (size > 10000000) {
39 return nullptr;
40 }
41 #endif
42 void* addr = sk_calloc_canfail(size);
43 if (nullptr == addr) {
44 return nullptr;
45 }
46
47 struct PixelRef final : public SkPixelRef {
48 PixelRef(int w, int h, void* s, size_t r) : SkPixelRef(w, h, s, r) {}
49 ~PixelRef() override { sk_free(this->pixels()); }
50 };
51 return sk_sp<SkPixelRef>(new PixelRef(info.width(), info.height(), addr, rowBytes));
52 }
53
MakeWithData(const SkImageInfo & info,size_t rowBytes,sk_sp<SkData> data)54 sk_sp<SkPixelRef> SkMallocPixelRef::MakeWithData(const SkImageInfo& info,
55 size_t rowBytes,
56 sk_sp<SkData> data) {
57 SkASSERT(data != nullptr);
58 if (!is_valid(info)) {
59 return nullptr;
60 }
61 // TODO: what should we return if computeByteSize returns 0?
62 // - the info was empty?
63 // - we overflowed computing the size?
64 if ((rowBytes < info.minRowBytes()) || (data->size() < info.computeByteSize(rowBytes))) {
65 return nullptr;
66 }
67 struct PixelRef final : public SkPixelRef {
68 sk_sp<SkData> fData;
69 PixelRef(int w, int h, void* s, size_t r, sk_sp<SkData> d)
70 : SkPixelRef(w, h, s, r), fData(std::move(d)) {}
71 };
72 void* pixels = const_cast<void*>(data->data());
73 sk_sp<SkPixelRef> pr(new PixelRef(info.width(), info.height(), pixels, rowBytes,
74 std::move(data)));
75 pr->setImmutable(); // since we were created with (immutable) data
76 return pr;
77 }
78