35ae8ea9be
git-svn-id: http://skia.googlecode.com/svn/trunk@1588 2bbb7eff-a529-9590-31e7-b0007b416f81
98 lines
3.0 KiB
C++
98 lines
3.0 KiB
C++
/*
|
|
Copyright 2011 Google Inc.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
|
|
#ifndef SkDataRef_DEFINED
|
|
#define SkDataRef_DEFINED
|
|
|
|
#include "SkRefCnt.h"
|
|
|
|
/**
|
|
* SkDataRef holds an immutable data buffer. Not only is the data immutable,
|
|
* but the actual ptr that is returned (by data() or bytes()) is guaranteed
|
|
* to always be the same for the life of this instance.
|
|
*/
|
|
class SkDataRef : public SkRefCnt {
|
|
public:
|
|
/**
|
|
* Returns the number of bytes stored.
|
|
*/
|
|
size_t size() const { return fSize; }
|
|
|
|
/**
|
|
* Returns the ptr to the data.
|
|
*/
|
|
const void* data() const { return fPtr; }
|
|
|
|
/**
|
|
* Like data(), returns a read-only ptr into the data, but in this case
|
|
* it is cast to uint8_t*, to make it easy to add an offset to it.
|
|
*/
|
|
const uint8_t* bytes() const {
|
|
return reinterpret_cast<const uint8_t*>(fPtr);
|
|
}
|
|
|
|
/**
|
|
* Helper to copy a range of the data into a caller-provided buffer.
|
|
* Returns the actual number of bytes copied, after clamping offset and
|
|
* length to the size of the data. If buffer is NULL, it is ignored, and
|
|
* only the computed number of bytes is returned.
|
|
*/
|
|
size_t copyRange(size_t offset, size_t length, void* buffer) const;
|
|
|
|
/**
|
|
* Function that, if provided, will be called when the SkDataRef goes out
|
|
* of scope, allowing for custom allocation/freeing of the data.
|
|
*/
|
|
typedef void (*ReleaseProc)(const void* ptr, size_t length, void* context);
|
|
|
|
/**
|
|
* Create a new dataref by copying the specified data
|
|
*/
|
|
static SkDataRef* NewWithCopy(const void* data, size_t length);
|
|
|
|
/**
|
|
* Create a new dataref, taking the data ptr as is, and using the
|
|
* releaseproc to free it. The proc may be NULL.
|
|
*/
|
|
static SkDataRef* NewWithProc(const void* data, size_t length,
|
|
ReleaseProc proc, void* context);
|
|
|
|
/**
|
|
* Create a new dataref using a subset of the data in the specified
|
|
* src dataref.
|
|
*/
|
|
static SkDataRef* NewSubset(const SkDataRef* src, size_t offset, size_t length);
|
|
|
|
/**
|
|
* Returns a new empty dataref (or a reference to a shared empty dataref).
|
|
* New or shared, the caller must see that unref() is eventually called.
|
|
*/
|
|
static SkDataRef* NewEmpty();
|
|
|
|
private:
|
|
ReleaseProc fReleaseProc;
|
|
void* fReleaseProcContext;
|
|
|
|
const void* fPtr;
|
|
size_t fSize;
|
|
|
|
SkDataRef(const void* ptr, size_t size, ReleaseProc, void* context);
|
|
~SkDataRef();
|
|
};
|
|
|
|
#endif
|