Wrap SkStreams in IStreams instead of copying data around.
http://codereview.appspot.com/4630062/
git-svn-id: http://skia.googlecode.com/svn/trunk@1694 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/utils/win/SkIStream.cpp b/src/utils/win/SkIStream.cpp
new file mode 100644
index 0000000..29e1c87
--- /dev/null
+++ b/src/utils/win/SkIStream.cpp
@@ -0,0 +1,263 @@
+/*
+ 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.
+ */
+
+#define WIN32_LEAN_AND_MEAN
+#include <Windows.h>
+#include <ole2.h>
+#include "SkIStream.h"
+#include "SkStream.h"
+
+/**
+ * SkBaseIStream
+ */
+SkBaseIStream::SkBaseIStream() : _refcount(1) { }
+SkBaseIStream::~SkBaseIStream() { }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::QueryInterface(REFIID iid
+ , void ** ppvObject)
+{
+ if (NULL == ppvObject) {
+ return E_INVALIDARG;
+ }
+ if (iid == __uuidof(IUnknown)
+ || iid == __uuidof(IStream)
+ || iid == __uuidof(ISequentialStream))
+ {
+ *ppvObject = static_cast<IStream*>(this);
+ AddRef();
+ return S_OK;
+ } else {
+ *ppvObject = NULL;
+ return E_NOINTERFACE;
+ }
+}
+
+ULONG STDMETHODCALLTYPE SkBaseIStream::AddRef(void) {
+ return (ULONG)InterlockedIncrement(&_refcount);
+}
+
+ULONG STDMETHODCALLTYPE SkBaseIStream::Release(void) {
+ ULONG res = (ULONG) InterlockedDecrement(&_refcount);
+ if (0 == res) {
+ delete this;
+ }
+ return res;
+}
+
+// ISequentialStream Interface
+HRESULT STDMETHODCALLTYPE SkBaseIStream::Read(void* pv
+ , ULONG cb
+ , ULONG* pcbRead)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::Write(void const* pv
+ , ULONG cb
+ , ULONG* pcbWritten)
+{ return E_NOTIMPL; }
+
+// IStream Interface
+HRESULT STDMETHODCALLTYPE SkBaseIStream::SetSize(ULARGE_INTEGER)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::CopyTo(IStream*
+ , ULARGE_INTEGER
+ , ULARGE_INTEGER*
+ , ULARGE_INTEGER*)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::Commit(DWORD)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::Revert(void)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::LockRegion(ULARGE_INTEGER
+ , ULARGE_INTEGER
+ , DWORD)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::UnlockRegion(ULARGE_INTEGER
+ , ULARGE_INTEGER
+ , DWORD)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::Clone(IStream **)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::Seek(LARGE_INTEGER liDistanceToMove
+ , DWORD dwOrigin
+ , ULARGE_INTEGER* lpNewFilePointer)
+{ return E_NOTIMPL; }
+
+HRESULT STDMETHODCALLTYPE SkBaseIStream::Stat(STATSTG* pStatstg
+ , DWORD grfStatFlag)
+{ return E_NOTIMPL; }
+
+
+/**
+ * SkIStream
+ */
+SkIStream::SkIStream(SkStream* stream, bool unrefOnRelease)
+ : SkBaseIStream()
+ , fSkStream(stream)
+ , fUnrefOnRelease(unrefOnRelease)
+{ }
+
+SkIStream::~SkIStream() {
+ if (NULL != this->fSkStream && fUnrefOnRelease) {
+ this->fSkStream->unref();
+ }
+}
+
+HRESULT SkIStream::CreateFromSkStream(SkStream* stream
+ , bool unrefOnRelease
+ , IStream ** ppStream)
+{
+ *ppStream = new SkIStream(stream, unrefOnRelease);
+ return S_OK;
+}
+
+// ISequentialStream Interface
+HRESULT STDMETHODCALLTYPE SkIStream::Read(void* pv, ULONG cb, ULONG* pcbRead) {
+ *pcbRead = this->fSkStream->read(pv, cb);
+ return (*pcbRead == cb) ? S_OK : S_FALSE;
+}
+
+HRESULT STDMETHODCALLTYPE SkIStream::Write(void const* pv
+ , ULONG cb
+ , ULONG* pcbWritten)
+{
+ return STG_E_CANTSAVE;
+}
+
+// IStream Interface
+HRESULT STDMETHODCALLTYPE SkIStream::Seek(LARGE_INTEGER liDistanceToMove
+ , DWORD dwOrigin
+ , ULARGE_INTEGER* lpNewFilePointer)
+{
+ if (lpNewFilePointer != NULL) {
+ (*lpNewFilePointer).QuadPart = NULL;
+ }
+
+ HRESULT hr = S_OK;
+ switch(dwOrigin) {
+ case STREAM_SEEK_SET: {
+ if (!this->fSkStream->rewind()) {
+ hr = E_FAIL;
+ } else {
+ size_t skipped = this->fSkStream->skip(
+ liDistanceToMove.QuadPart
+ );
+ if (skipped != liDistanceToMove.QuadPart) {
+ hr = E_FAIL;
+ }
+ }
+ break;
+ }
+ case STREAM_SEEK_CUR: {
+ size_t skipped = this->fSkStream->skip(liDistanceToMove.QuadPart);
+ if (skipped != liDistanceToMove.QuadPart) {
+ hr = E_FAIL;
+ }
+ break;
+ }
+ case STREAM_SEEK_END: {
+ if (!this->fSkStream->rewind()) {
+ hr = E_FAIL;
+ } else {
+ size_t skipped = this->fSkStream->skip(
+ this->fSkStream->getLength() + liDistanceToMove.QuadPart
+ );
+ if (skipped != liDistanceToMove.QuadPart) {
+ hr = E_FAIL;
+ }
+ }
+ break;
+ }
+ default:
+ hr = STG_E_INVALIDFUNCTION;
+ break;
+ }
+
+ return hr;
+}
+
+HRESULT STDMETHODCALLTYPE SkIStream::Stat(STATSTG* pStatstg
+ , DWORD grfStatFlag)
+{
+ if (0 == grfStatFlag & STATFLAG_NONAME) {
+ return STG_E_INVALIDFLAG;
+ }
+ pStatstg->pwcsName = NULL;
+ pStatstg->cbSize.QuadPart = this->fSkStream->getLength();
+ pStatstg->clsid = CLSID_NULL;
+ pStatstg->type = STGTY_STREAM;
+ pStatstg->grfMode = STGM_READ;
+ return S_OK;
+}
+
+
+/**
+ * SkIWStream
+ */
+SkWIStream::SkWIStream(SkWStream* stream)
+ : SkBaseIStream()
+ , fSkWStream(stream)
+{ }
+
+SkWIStream::~SkWIStream() {
+ if (NULL != this->fSkWStream) {
+ this->fSkWStream->flush();
+ }
+}
+
+HRESULT SkWIStream::CreateFromSkWStream(SkWStream* stream
+ , IStream ** ppStream)
+{
+ *ppStream = new SkWIStream(stream);
+ return S_OK;
+}
+
+// ISequentialStream Interface
+HRESULT STDMETHODCALLTYPE SkWIStream::Write(void const* pv
+ , ULONG cb
+ , ULONG* pcbWritten)
+{
+ HRESULT hr = S_OK;
+ bool wrote = this->fSkWStream->write(pv, cb);
+ if (wrote) {
+ *pcbWritten = cb;
+ } else {
+ *pcbWritten = 0;
+ hr = S_FALSE;
+ }
+ return hr;
+}
+
+// IStream Interface
+HRESULT STDMETHODCALLTYPE SkWIStream::Stat(STATSTG* pStatstg
+ , DWORD grfStatFlag)
+{
+ if (0 == grfStatFlag & STATFLAG_NONAME) {
+ return STG_E_INVALIDFLAG;
+ }
+ pStatstg->pwcsName = NULL;
+ pStatstg->cbSize.QuadPart = 0;
+ pStatstg->clsid = CLSID_NULL;
+ pStatstg->type = STGTY_STREAM;
+ pStatstg->grfMode = STGM_WRITE;
+ return S_OK;
+}