AuroraMiddleware/skia2
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

add safemath version of readbuffer->skip

Browse Source 
Bug: skia:
Change-Id: I6a5d24569cc1bd93bd190d81e3375993da9c56f0
Reviewed-on: https://skia-review.googlesource.com/88581
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Herb Derby <herb@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
This commit is contained in:
Mike Reed 2017-12-21 21:54:32 -05:00 committed by Skia Commit-Bot
parent bdc453db78
commit 5c68dce775
5 changed files with 45 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
src/core/SkMath.cpp
View File

@ -9,6 +9,7 @@
#include "SkFixed.h"
#include "SkFloatBits.h"
#include "SkFloatingPoint.h"
#include "SkSafeMath.h"
#include "SkScalar.h"
#define sub_shift(zeros, x, n) \
@ -67,8 +68,6 @@ int32_t SkSqrtBits(int32_t x, int count) {
return root;
}
///////////////////////////////////////////////////////////////////////////////
float SkScalarSinCos(float radians, float* cosValue) {
float sinValue = sk_float_sin(radians);
@ -84,3 +83,17 @@ float SkScalarSinCos(float radians, float* cosValue) {
}
return sinValue;
}
///////////////////////////////////////////////////////////////////////////////////////////////////
size_t SkSafeMath::Add(size_t x, size_t y) {
SkSafeMath tmp;
size_t sum = tmp.add(x, y);
return tmp.ok() ? sum : SK_MaxSizeT;
}
size_t SkSafeMath::Mul(size_t x, size_t y) {
SkSafeMath tmp;
size_t prod = tmp.mul(x, y);
return tmp.ok() ? prod : SK_MaxSizeT;
}

38
src/core/SkPicturePlayback.cpp
View File

@ -14,6 +14,7 @@
#include "SkPictureRecord.h"
#include "SkReadBuffer.h"
#include "SkRSXform.h"
#include "SkSafeMath.h"
#include "SkTextBlob.h"
#include "SkTDArray.h"
#include "SkTypes.h"
@ -246,12 +247,12 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
const SkImage* atlas = fPictureData->getImage(reader);
const uint32_t flags = reader->readUInt();
const int count = reader->readUInt();
const SkRSXform* xform = (const SkRSXform*)reader->skip(count * sizeof(SkRSXform));
const SkRect* tex = (const SkRect*)reader->skip(count * sizeof(SkRect));
const SkRSXform* xform = (const SkRSXform*)reader->skip(count, sizeof(SkRSXform));
const SkRect* tex = (const SkRect*)reader->skip(count, sizeof(SkRect));
const SkColor* colors = nullptr;
SkBlendMode mode = SkBlendMode::kDst;
if (flags & DRAW_ATLAS_HAS_COLORS) {
colors = (const SkColor*)reader->skip(count * sizeof(SkColor));
colors = (const SkColor*)reader->skip(count, sizeof(SkColor));
mode = (SkBlendMode)reader->readUInt();
}
const SkRect* cull = nullptr;
@ -360,9 +361,9 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
const SkImage* image = fPictureData->getImage(reader);
SkCanvas::Lattice lattice;
lattice.fXCount = reader->readInt();
lattice.fXDivs = (const int*) reader->skip(lattice.fXCount * sizeof(int32_t));
lattice.fXDivs = (const int*) reader->skip(lattice.fXCount, sizeof(int32_t));
lattice.fYCount = reader->readInt();
lattice.fYDivs = (const int*) reader->skip(lattice.fYCount * sizeof(int32_t));
lattice.fYDivs = (const int*) reader->skip(lattice.fYCount, sizeof(int32_t));
int flagCount = reader->readInt();
lattice.fRectTypes = (0 == flagCount) ? nullptr :
(const SkCanvas::Lattice::RectType*)
@ -427,16 +428,16 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
case DRAW_PATCH: {
const SkPaint* paint = fPictureData->getPaint(reader);
const SkPoint* cubics = (const SkPoint*)reader->skip(SkPatchUtils::kNumCtrlPts *
const SkPoint* cubics = (const SkPoint*)reader->skip(SkPatchUtils::kNumCtrlPts,
sizeof(SkPoint));
uint32_t flag = reader->readInt();
const SkColor* colors = nullptr;
if (flag & DRAW_VERTICES_HAS_COLORS) {
colors = (const SkColor*)reader->skip(SkPatchUtils::kNumCorners * sizeof(SkColor));
colors = (const SkColor*)reader->skip(SkPatchUtils::kNumCorners, sizeof(SkColor));
}
const SkPoint* texCoords = nullptr;
if (flag & DRAW_VERTICES_HAS_TEXS) {
texCoords = (const SkPoint*)reader->skip(SkPatchUtils::kNumCorners *
texCoords = (const SkPoint*)reader->skip(SkPatchUtils::kNumCorners,
sizeof(SkPoint));
}
SkBlendMode bmode = SkBlendMode::kModulate;
@ -480,7 +481,7 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
const SkPaint* paint = fPictureData->getPaint(reader);
SkCanvas::PointMode mode = (SkCanvas::PointMode)reader->readInt();
size_t count = reader->readInt();
const SkPoint* pts = (const SkPoint*)reader->skip(sizeof(SkPoint)* count);
const SkPoint* pts = (const SkPoint*)reader->skip(count, sizeof(SkPoint));
BREAK_ON_READ_ERROR(reader);
if (paint) {
@ -492,7 +493,7 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
TextContainer text(reader, paint);
size_t points = reader->readInt();
reader->validate(points == text.count());
const SkPoint* pos = (const SkPoint*)reader->skip(points * sizeof(SkPoint));
const SkPoint* pos = (const SkPoint*)reader->skip(points, sizeof(SkPoint));
BREAK_ON_READ_ERROR(reader);
if (paint && text.text()) {
@ -504,7 +505,7 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
TextContainer text(reader, paint);
size_t points = reader->readInt();
reader->validate(points == text.count());
const SkPoint* pos = (const SkPoint*)reader->skip(points * sizeof(SkPoint));
const SkPoint* pos = (const SkPoint*)reader->skip(points, sizeof(SkPoint));
const SkScalar top = reader->readScalar();
const SkScalar bottom = reader->readScalar();
SkDebugf("postexth count %zu pos %p\n", points, pos);
@ -521,7 +522,7 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
size_t xCount = reader->readInt();
reader->validate(xCount == text.count());
const SkScalar constY = reader->readScalar();
const SkScalar* xpos = (const SkScalar*)reader->skip(xCount * sizeof(SkScalar));
const SkScalar* xpos = (const SkScalar*)reader->skip(xCount, sizeof(SkScalar));
BREAK_ON_READ_ERROR(reader);
if (paint && text.text()) {
@ -533,7 +534,8 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
TextContainer text(reader, paint);
size_t xCount = reader->readInt();
reader->validate(xCount == text.count());
const SkScalar* xpos = (const SkScalar*)reader->skip((3 + xCount) * sizeof(SkScalar));
const SkScalar* xpos = (const SkScalar*)reader->skip(SkSafeMath::Add(3, xCount),
sizeof(SkScalar));
BREAK_ON_READ_ERROR(reader);
const SkScalar top = *xpos++;
@ -651,7 +653,7 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
int count = reader->readInt();
uint32_t flags = reader->read32();
TextContainer text(reader, paint);
const SkRSXform* xform = (const SkRSXform*)reader->skip(count * sizeof(SkRSXform));
const SkRSXform* xform = (const SkRSXform*)reader->skip(count, sizeof(SkRSXform));
const SkRect* cull = nullptr;
if (flags & DRAW_TEXT_RSXFORM_HAS_CULL) {
cull = (const SkRect*)reader->skip(sizeof(SkRect));
@ -667,20 +669,20 @@ void SkPicturePlayback::handleOp(SkReadBuffer* reader,
DrawVertexFlags flags = (DrawVertexFlags)reader->readInt();
SkVertices::VertexMode vmode = (SkVertices::VertexMode)reader->readInt();
int vCount = reader->readInt();
const SkPoint* verts = (const SkPoint*)reader->skip(vCount * sizeof(SkPoint));
const SkPoint* verts = (const SkPoint*)reader->skip(vCount, sizeof(SkPoint));
const SkPoint* texs = nullptr;
const SkColor* colors = nullptr;
const uint16_t* indices = nullptr;
int iCount = 0;
if (flags & DRAW_VERTICES_HAS_TEXS) {
texs = (const SkPoint*)reader->skip(vCount * sizeof(SkPoint));
texs = (const SkPoint*)reader->skip(vCount, sizeof(SkPoint));
}
if (flags & DRAW_VERTICES_HAS_COLORS) {
colors = (const SkColor*)reader->skip(vCount * sizeof(SkColor));
colors = (const SkColor*)reader->skip(vCount, sizeof(SkColor));
}
if (flags & DRAW_VERTICES_HAS_INDICES) {
iCount = reader->readInt();
indices = (const uint16_t*)reader->skip(iCount * sizeof(uint16_t));
indices = (const uint16_t*)reader->skip(iCount, sizeof(uint16_t));
}
SkBlendMode bmode = SkBlendMode::kModulate;
if (flags & DRAW_VERTICES_HAS_XFER) {

5
src/core/SkReadBuffer.cpp
View File

@ -13,6 +13,7 @@
#include "SkMathPriv.h"
#include "SkMatrixPriv.h"
#include "SkReadBuffer.h"
#include "SkSafeMath.h"
#include "SkStream.h"
#include "SkTypeface.h"
@ -106,6 +107,10 @@ const void* SkReadBuffer::skip(size_t size) {
return addr;
}
const void* SkReadBuffer::skip(size_t count, size_t size) {
return this->skip(SkSafeMath::Mul(count, size));
}
void SkReadBuffer::setDeserialProcs(const SkDeserialProcs& procs) {
fProcs = procs;
}

1
src/core/SkReadBuffer.h
View File

@ -115,6 +115,7 @@ public:
size_t offset() { return fReader.offset(); }
bool eof() { return fReader.eof(); }
const void* skip(size_t size);
const void* skip(size_t count, size_t size); // does safe multiply
// primitives
bool readBool();

4
src/core/SkSafeMath.h
View File

@ -48,6 +48,10 @@ public:
return add(x, alignment - 1) & ~(alignment - 1);
}
// These saturate to their results
static size_t Add(size_t x, size_t y);
static size_t Mul(size_t x, size_t y);
private:
uint32_t mul32(uint32_t x, uint32_t y) {
uint64_t bx = x;