/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ /* vim:set ts=4 sts=4 sw=4 cin et: */ /* 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/. */ /** * Based on original code from nsIStringStream.cpp */ #include "IPC/IPCMessageUtils.h" #include "nsStringStream.h" #include "nsStreamUtils.h" #include "nsReadableUtils.h" #include "nsISeekableStream.h" #include "nsISupportsPrimitives.h" #include "nsCRT.h" #include "prerror.h" #include "plstr.h" #include "nsIClassInfoImpl.h" #include "nsIIPCSerializable.h" #include "mozilla/Attributes.h" //----------------------------------------------------------------------------- // nsIStringInputStream implementation //----------------------------------------------------------------------------- class nsStringInputStream MOZ_FINAL : public nsIStringInputStream , public nsISeekableStream , public nsISupportsCString , public nsIIPCSerializable { public: NS_DECL_ISUPPORTS NS_DECL_NSIINPUTSTREAM NS_DECL_NSISTRINGINPUTSTREAM NS_DECL_NSISEEKABLESTREAM NS_DECL_NSISUPPORTSPRIMITIVE NS_DECL_NSISUPPORTSCSTRING NS_DECL_NSIIPCSERIALIZABLE nsStringInputStream() { Clear(); } private: ~nsStringInputStream() {} PRUint32 Length() const { return mData.Length(); } PRUint32 LengthRemaining() const { return Length() - mOffset; } void Clear() { mData.SetIsVoid(true); } bool Closed() { return mData.IsVoid(); } nsDependentCSubstring mData; PRUint32 mOffset; }; // This class needs to support threadsafe refcounting since people often // allocate a string stream, and then read it from a background thread. NS_IMPL_THREADSAFE_ADDREF(nsStringInputStream) NS_IMPL_THREADSAFE_RELEASE(nsStringInputStream) NS_IMPL_CLASSINFO(nsStringInputStream, NULL, nsIClassInfo::THREADSAFE, NS_STRINGINPUTSTREAM_CID) NS_IMPL_QUERY_INTERFACE5_CI(nsStringInputStream, nsIStringInputStream, nsIInputStream, nsISupportsCString, nsISeekableStream, nsIIPCSerializable) NS_IMPL_CI_INTERFACE_GETTER5(nsStringInputStream, nsIStringInputStream, nsIInputStream, nsISupportsCString, nsISeekableStream, nsIIPCSerializable) ///////// // nsISupportsCString implementation ///////// NS_IMETHODIMP nsStringInputStream::GetType(PRUint16 *type) { *type = TYPE_CSTRING; return NS_OK; } NS_IMETHODIMP nsStringInputStream::GetData(nsACString &data) { // The stream doesn't have any data when it is closed. We could fake it // and return an empty string here, but it seems better to keep this return // value consistent with the behavior of the other 'getter' methods. NS_ENSURE_TRUE(!Closed(), NS_BASE_STREAM_CLOSED); data.Assign(mData); return NS_OK; } NS_IMETHODIMP nsStringInputStream::SetData(const nsACString &data) { mData.Assign(data); mOffset = 0; return NS_OK; } NS_IMETHODIMP nsStringInputStream::ToString(char **result) { // NOTE: This method may result in data loss, so we do not implement it. return NS_ERROR_NOT_IMPLEMENTED; } ///////// // nsIStringInputStream implementation ///////// NS_IMETHODIMP nsStringInputStream::SetData(const char *data, PRInt32 dataLen) { NS_ENSURE_ARG_POINTER(data); mData.Assign(data, dataLen); mOffset = 0; return NS_OK; } NS_IMETHODIMP nsStringInputStream::AdoptData(char *data, PRInt32 dataLen) { NS_ENSURE_ARG_POINTER(data); mData.Adopt(data, dataLen); mOffset = 0; return NS_OK; } NS_IMETHODIMP nsStringInputStream::ShareData(const char *data, PRInt32 dataLen) { NS_ENSURE_ARG_POINTER(data); if (dataLen < 0) dataLen = strlen(data); mData.Rebind(data, dataLen); mOffset = 0; return NS_OK; } ///////// // nsIInputStream implementation ///////// NS_IMETHODIMP nsStringInputStream::Close() { Clear(); return NS_OK; } NS_IMETHODIMP nsStringInputStream::Available(PRUint32 *aLength) { NS_ASSERTION(aLength, "null ptr"); if (Closed()) return NS_BASE_STREAM_CLOSED; *aLength = LengthRemaining(); return NS_OK; } NS_IMETHODIMP nsStringInputStream::Read(char* aBuf, PRUint32 aCount, PRUint32 *aReadCount) { NS_ASSERTION(aBuf, "null ptr"); return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, aReadCount); } NS_IMETHODIMP nsStringInputStream::ReadSegments(nsWriteSegmentFun writer, void *closure, PRUint32 aCount, PRUint32 *result) { NS_ASSERTION(result, "null ptr"); NS_ASSERTION(Length() >= mOffset, "bad stream state"); if (Closed()) return NS_BASE_STREAM_CLOSED; // We may be at end-of-file PRUint32 maxCount = LengthRemaining(); if (maxCount == 0) { *result = 0; return NS_OK; } if (aCount > maxCount) aCount = maxCount; nsresult rv = writer(this, closure, mData.BeginReading() + mOffset, 0, aCount, result); if (NS_SUCCEEDED(rv)) { NS_ASSERTION(*result <= aCount, "writer should not write more than we asked it to write"); mOffset += *result; } // errors returned from the writer end here! return NS_OK; } NS_IMETHODIMP nsStringInputStream::IsNonBlocking(bool *aNonBlocking) { *aNonBlocking = true; return NS_OK; } ///////// // nsISeekableStream implementation ///////// NS_IMETHODIMP nsStringInputStream::Seek(PRInt32 whence, PRInt64 offset) { if (Closed()) return NS_BASE_STREAM_CLOSED; // Compute new stream position. The given offset may be a negative value. PRInt64 newPos = offset; switch (whence) { case NS_SEEK_SET: break; case NS_SEEK_CUR: newPos += mOffset; break; case NS_SEEK_END: newPos += Length(); break; default: NS_ERROR("invalid whence"); return NS_ERROR_INVALID_ARG; } NS_ENSURE_ARG(newPos >= 0); NS_ENSURE_ARG(newPos <= Length()); mOffset = (PRUint32)newPos; return NS_OK; } NS_IMETHODIMP nsStringInputStream::Tell(PRInt64* outWhere) { if (Closed()) return NS_BASE_STREAM_CLOSED; *outWhere = mOffset; return NS_OK; } NS_IMETHODIMP nsStringInputStream::SetEOF() { if (Closed()) return NS_BASE_STREAM_CLOSED; mOffset = Length(); return NS_OK; } ///////// // nsIIPCSerializable implementation ///////// bool nsStringInputStream::Read(const IPC::Message *aMsg, void **aIter) { using IPC::ReadParam; nsCString value; if (!ReadParam(aMsg, aIter, &value)) return false; nsresult rv = SetData(value); if (NS_FAILED(rv)) return false; return true; } void nsStringInputStream::Write(IPC::Message *aMsg) { using IPC::WriteParam; WriteParam(aMsg, static_cast(PromiseFlatCString(mData))); } nsresult NS_NewByteInputStream(nsIInputStream** aStreamResult, const char* aStringToRead, PRInt32 aLength, nsAssignmentType aAssignment) { NS_PRECONDITION(aStreamResult, "null out ptr"); nsStringInputStream* stream = new nsStringInputStream(); if (! stream) return NS_ERROR_OUT_OF_MEMORY; NS_ADDREF(stream); nsresult rv; switch (aAssignment) { case NS_ASSIGNMENT_COPY: rv = stream->SetData(aStringToRead, aLength); break; case NS_ASSIGNMENT_DEPEND: rv = stream->ShareData(aStringToRead, aLength); break; case NS_ASSIGNMENT_ADOPT: rv = stream->AdoptData(const_cast(aStringToRead), aLength); break; default: NS_ERROR("invalid assignment type"); rv = NS_ERROR_INVALID_ARG; } if (NS_FAILED(rv)) { NS_RELEASE(stream); return rv; } *aStreamResult = stream; return NS_OK; } nsresult NS_NewStringInputStream(nsIInputStream** aStreamResult, const nsAString& aStringToRead) { NS_LossyConvertUTF16toASCII data(aStringToRead); // truncates high-order bytes return NS_NewCStringInputStream(aStreamResult, data); } nsresult NS_NewCStringInputStream(nsIInputStream** aStreamResult, const nsACString& aStringToRead) { NS_PRECONDITION(aStreamResult, "null out ptr"); nsStringInputStream* stream = new nsStringInputStream(); if (! stream) return NS_ERROR_OUT_OF_MEMORY; NS_ADDREF(stream); stream->SetData(aStringToRead); *aStreamResult = stream; return NS_OK; } // factory method for constructing a nsStringInputStream object nsresult nsStringInputStreamConstructor(nsISupports *outer, REFNSIID iid, void **result) { *result = nsnull; NS_ENSURE_TRUE(!outer, NS_ERROR_NO_AGGREGATION); nsStringInputStream *inst = new nsStringInputStream(); if (!inst) return NS_ERROR_OUT_OF_MEMORY; NS_ADDREF(inst); nsresult rv = inst->QueryInterface(iid, result); NS_RELEASE(inst); return rv; }