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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 <algorithm>
#include "ArrayBufferInputStream.h"
#include "nsStreamUtils.h"
#include "js/ArrayBuffer.h" // JS::{GetArrayBuffer{ByteLength,Data},IsArrayBufferObject}
#include "js/RootingAPI.h" // JS::{Handle,Rooted}
#include "js/Value.h" // JS::Value
#include "mozilla/UniquePtrExtensions.h"
#include "mozilla/dom/ScriptSettings.h"
using mozilla::dom::RootingCx;
NS_IMPL_ISUPPORTS(ArrayBufferInputStream, nsIArrayBufferInputStream,
nsIInputStream);
ArrayBufferInputStream::ArrayBufferInputStream()
: mBufferLength(0), mPos(0), mClosed(false) {}
NS_IMETHODIMP
ArrayBufferInputStream::SetData(JS::Handle<JS::Value> aBuffer,
uint32_t aByteOffset, uint32_t aLength) {
NS_ASSERT_OWNINGTHREAD(ArrayBufferInputStream);
if (!aBuffer.isObject()) {
return NS_ERROR_FAILURE;
}
JS::Rooted<JSObject*> arrayBuffer(RootingCx(), &aBuffer.toObject());
if (!JS::IsArrayBufferObject(arrayBuffer)) {
return NS_ERROR_FAILURE;
}
uint32_t buflen = JS::GetArrayBufferByteLength(arrayBuffer);
uint32_t offset = std::min(buflen, aByteOffset);
uint32_t bufferLength = std::min(buflen - offset, aLength);
mArrayBuffer = mozilla::MakeUniqueFallible<char[]>(bufferLength);
if (!mArrayBuffer) {
return NS_ERROR_OUT_OF_MEMORY;
}
mBufferLength = bufferLength;
JS::AutoCheckCannotGC nogc;
bool isShared;
char* src =
(char*)JS::GetArrayBufferData(arrayBuffer, &isShared, nogc) + offset;
memcpy(&mArrayBuffer[0], src, mBufferLength);
return NS_OK;
}
NS_IMETHODIMP
ArrayBufferInputStream::Close() {
mClosed = true;
return NS_OK;
}
NS_IMETHODIMP
ArrayBufferInputStream::Available(uint64_t* aCount) {
if (mClosed) {
return NS_BASE_STREAM_CLOSED;
}
if (mArrayBuffer) {
*aCount = mBufferLength ? mBufferLength - mPos : 0;
} else {
*aCount = 0;
}
return NS_OK;
}
NS_IMETHODIMP
ArrayBufferInputStream::Read(char* aBuf, uint32_t aCount,
uint32_t* aReadCount) {
return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, aReadCount);
}
NS_IMETHODIMP
ArrayBufferInputStream::ReadSegments(nsWriteSegmentFun writer, void* closure,
uint32_t aCount, uint32_t* result) {
NS_ASSERTION(result, "null ptr");
NS_ASSERTION(mBufferLength >= mPos, "bad stream state");
if (mClosed) {
return NS_BASE_STREAM_CLOSED;
}
MOZ_ASSERT(mArrayBuffer || (mPos == mBufferLength),
"stream inited incorrectly");
*result = 0;
while (mPos < mBufferLength) {
uint32_t remaining = mBufferLength - mPos;
MOZ_ASSERT(mArrayBuffer);
uint32_t count = std::min(aCount, remaining);
if (count == 0) {
break;
}
uint32_t written;
nsresult rv = writer(this, closure, &mArrayBuffer[0] + mPos, *result, count,
&written);
if (NS_FAILED(rv)) {
// InputStreams do not propagate errors to caller.
return NS_OK;
}
NS_ASSERTION(written <= count,
"writer should not write more than we asked it to write");
mPos += written;
*result += written;
aCount -= written;
}
return NS_OK;
}
NS_IMETHODIMP
ArrayBufferInputStream::IsNonBlocking(bool* aNonBlocking) {
*aNonBlocking = true;
return NS_OK;
}