gecko-dev/dom/file/Blob.h

162 строки
5.8 KiB
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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_dom_Blob_h
#define mozilla_dom_Blob_h
#include "mozilla/dom/BodyConsumer.h"
#include "nsCycleCollectionParticipant.h"
#include "nsCOMPtr.h"
#include "nsWrapperCache.h"
#include "nsWeakReference.h"
class nsIGlobalObject;
class nsIInputStream;
namespace mozilla {
class ErrorResult;
namespace dom {
struct BlobPropertyBag;
class BlobImpl;
class File;
class GlobalObject;
class OwningArrayBufferViewOrArrayBufferOrBlobOrUTF8String;
class Promise;
class ReadableStream;
#define NS_DOM_BLOB_IID \
{ \
0x648c2a83, 0xbdb1, 0x4a7d, { \
0xb5, 0x0a, 0xca, 0xcd, 0x92, 0x87, 0x45, 0xc2 \
} \
}
class Blob : public nsSupportsWeakReference, public nsWrapperCache {
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS_FINAL
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(Blob)
NS_DECLARE_STATIC_IID_ACCESSOR(NS_DOM_BLOB_IID)
using BlobPart = OwningArrayBufferViewOrArrayBufferOrBlobOrUTF8String;
// This creates a Blob or a File based on the type of BlobImpl.
static Blob* Create(nsIGlobalObject* aGlobal, BlobImpl* aImpl);
static already_AddRefed<Blob> CreateStringBlob(nsIGlobalObject* aGlobal,
const nsACString& aData,
const nsAString& aContentType);
// The returned Blob takes ownership of aMemoryBuffer. aMemoryBuffer will be
// freed by free so it must be allocated by malloc or something
// compatible with it.
static already_AddRefed<Blob> CreateMemoryBlob(nsIGlobalObject* aGlobal,
void* aMemoryBuffer,
uint64_t aLength,
const nsAString& aContentType);
BlobImpl* Impl() const { return mImpl; }
bool IsFile() const;
const nsTArray<RefPtr<BlobImpl>>* GetSubBlobImpls() const;
// This method returns null if this Blob is not a File; it returns
// the same object in case this Blob already implements the File interface;
// otherwise it returns a new File object with the same BlobImpl.
already_AddRefed<File> ToFile();
// This method creates a new File object with the given name and the same
// BlobImpl.
already_AddRefed<File> ToFile(const nsAString& aName, ErrorResult& aRv) const;
already_AddRefed<Blob> CreateSlice(uint64_t aStart, uint64_t aLength,
const nsAString& aContentType,
ErrorResult& aRv) const;
void CreateInputStream(nsIInputStream** aStream, ErrorResult& aRv) const;
int64_t GetFileId() const;
// A utility function that enforces the spec constraints on the type of a
// blob: no codepoints outside the ASCII range (otherwise type becomes empty)
// and lowercase ASCII only. We can't just use our existing nsContentUtils
// ASCII-related helpers because we need the "outside ASCII range" check, and
// we can't use NS_IsAscii because its definition of "ASCII" (chars all <=
// 0x7E) differs from the file API definition (which excludes control chars).
static void MakeValidBlobType(nsAString& aType);
// WebIDL methods
nsIGlobalObject* GetParentObject() const { return mGlobal; }
bool IsMemoryFile() const;
// Blob constructor
static already_AddRefed<Blob> Constructor(
const GlobalObject& aGlobal, const Optional<Sequence<BlobPart>>& aData,
const BlobPropertyBag& aBag, ErrorResult& aRv);
JSObject* WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) override;
uint64_t GetSize(ErrorResult& aRv);
void GetType(nsAString& aType);
void GetBlobImplType(nsAString& aBlobImplType);
already_AddRefed<Blob> Slice(const Optional<int64_t>& aStart,
const Optional<int64_t>& aEnd,
const Optional<nsAString>& aContentType,
ErrorResult& aRv);
size_t GetAllocationSize() const;
nsresult GetSendInfo(nsIInputStream** aBody, uint64_t* aContentLength,
nsACString& aContentType, nsACString& aCharset) const;
already_AddRefed<ReadableStream> Stream(JSContext* aCx,
ErrorResult& aRv) const;
already_AddRefed<Promise> Text(ErrorResult& aRv) const;
already_AddRefed<Promise> ArrayBuffer(ErrorResult& aRv) const;
protected:
// File constructor should never be used directly. Use Blob::Create instead.
Blob(nsIGlobalObject* aGlobal, BlobImpl* aImpl);
virtual ~Blob();
virtual bool HasFileInterface() const { return false; }
already_AddRefed<Promise> ConsumeBody(BodyConsumer::ConsumeType aConsumeType,
ErrorResult& aRv) const;
// The member is the real backend implementation of this File/Blob.
// It's thread-safe and not CC-able and it's the only element that is moved
// between threads.
// Note: we should not store any other state in this class!
RefPtr<BlobImpl> mImpl;
private:
nsCOMPtr<nsIGlobalObject> mGlobal;
};
NS_DEFINE_STATIC_IID_ACCESSOR(Blob, NS_DOM_BLOB_IID)
// Override BindingJSObjectMallocBytes for blobs to tell the JS GC how much
// memory is held live by the binding object.
size_t BindingJSObjectMallocBytes(Blob* aBlob);
} // namespace dom
} // namespace mozilla
inline nsISupports* ToSupports(mozilla::dom::Blob* aBlob) {
return static_cast<nsISupportsWeakReference*>(aBlob);
}
#endif // mozilla_dom_Blob_h