mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-30 08:12:05 +00:00
75 lines
2.7 KiB
Plaintext
75 lines
2.7 KiB
Plaintext
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
|
|
* 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/. */
|
|
|
|
#include "nsISupports.idl"
|
|
#include "nsrootidl.idl"
|
|
|
|
interface nsIMemory;
|
|
interface nsIInputStream;
|
|
interface nsIOutputStream;
|
|
|
|
/**
|
|
* The nsIStorageStream interface maintains an internal data buffer that can be
|
|
* filled using a single output stream. One or more independent input streams
|
|
* can be created to read the data from the buffer non-destructively.
|
|
*/
|
|
|
|
[scriptable, uuid(604ad9d0-753e-11d3-90ca-34278643278f)]
|
|
interface nsIStorageStream : nsISupports
|
|
{
|
|
/**
|
|
*
|
|
* Initialize the stream, setting up the amount of space that will be
|
|
* allocated for the stream's backing-store.
|
|
*
|
|
* @param segmentSize
|
|
* Size of each segment. Must be a power of two.
|
|
* @param maxSize
|
|
* Maximum total size of this stream. length will always be less
|
|
* than or equal to this value. Passing UINT32_MAX is safe.
|
|
* @param segmentAllocator
|
|
* Which allocator to use for the segments. May be null, in which
|
|
* case a default allocator will be used.
|
|
*/
|
|
void init(in uint32_t segmentSize, in uint32_t maxSize, in nsIMemory segmentAllocator);
|
|
|
|
/**
|
|
* Get a reference to the one and only output stream for this instance.
|
|
* The zero-based startPosition argument is used is used to set the initial
|
|
* write cursor position. The startPosition cannot be set larger than the
|
|
* current buffer length. Calling this method has the side-effect of
|
|
* truncating the internal buffer to startPosition bytes.
|
|
*/
|
|
nsIOutputStream getOutputStream(in int32_t startPosition);
|
|
|
|
/**
|
|
* Create a new input stream to read data (written by the singleton output
|
|
* stream) from the internal buffer. Multiple, independent input streams
|
|
* can be created.
|
|
*/
|
|
nsIInputStream newInputStream(in int32_t startPosition);
|
|
|
|
/**
|
|
* The length attribute indicates the total number of bytes stored in the
|
|
* nsIStorageStream internal buffer, regardless of any consumption by input
|
|
* streams. Assigning to the length field can be used to truncate the
|
|
* buffer data, but can not be used when either the instance's output
|
|
* stream is in use.
|
|
*
|
|
* @See #writeInProgress */
|
|
attribute uint32_t length;
|
|
|
|
/**
|
|
* True, when output stream has not yet been Close'ed
|
|
*/
|
|
readonly attribute boolean writeInProgress;
|
|
};
|
|
|
|
%{C++
|
|
// Factory method
|
|
nsresult
|
|
NS_NewStorageStream(uint32_t segmentSize, uint32_t maxSize, nsIStorageStream **result);
|
|
%}
|