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/* -*- Mode: C++; tab-width: 2; 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 "IEnumFE.h"
#include "nsAlgorithm.h"
#include <algorithm>
CEnumFormatEtc::CEnumFormatEtc() : mRefCnt(0), mCurrentIdx(0) {}
// Constructor used by Clone()
CEnumFormatEtc::CEnumFormatEtc(nsTArray<FormatEtc>& aArray)
: mRefCnt(0), mCurrentIdx(0) {
// a deep copy, calls FormatEtc's copy constructor on each
mFormatList.AppendElements(aArray);
}
CEnumFormatEtc::~CEnumFormatEtc() {}
/* IUnknown impl. */
STDMETHODIMP
CEnumFormatEtc::QueryInterface(REFIID riid, LPVOID* ppv) {
*ppv = nullptr;
if (IsEqualIID(riid, IID_IUnknown) || IsEqualIID(riid, IID_IEnumFORMATETC))
*ppv = (LPVOID)this;
if (*ppv == nullptr) return E_NOINTERFACE;
// AddRef any interface we'll return.
((LPUNKNOWN)*ppv)->AddRef();
return S_OK;
}
STDMETHODIMP_(ULONG)
CEnumFormatEtc::AddRef() {
++mRefCnt;
NS_LOG_ADDREF(this, mRefCnt, "CEnumFormatEtc", sizeof(*this));
return mRefCnt;
}
STDMETHODIMP_(ULONG)
CEnumFormatEtc::Release() {
uint32_t refReturn;
refReturn = --mRefCnt;
NS_LOG_RELEASE(this, mRefCnt, "CEnumFormatEtc");
if (mRefCnt == 0) delete this;
return refReturn;
}
/* IEnumFORMATETC impl. */
STDMETHODIMP
CEnumFormatEtc::Next(ULONG aMaxToFetch, FORMATETC* aResult,
ULONG* aNumFetched) {
// If the method retrieves the number of items requested, the return
// value is S_OK. Otherwise, it is S_FALSE.
if (aNumFetched) *aNumFetched = 0;
// aNumFetched can be null if aMaxToFetch is 1
if (!aNumFetched && aMaxToFetch > 1) return S_FALSE;
if (!aResult) return S_FALSE;
// We're done walking the list
if (mCurrentIdx >= mFormatList.Length()) return S_FALSE;
uint32_t left = mFormatList.Length() - mCurrentIdx;
if (!aMaxToFetch) return S_FALSE;
uint32_t count = std::min(static_cast<uint32_t>(aMaxToFetch), left);
uint32_t idx = 0;
while (count > 0) {
// Copy out to aResult
mFormatList[mCurrentIdx++].CopyOut(&aResult[idx++]);
count--;
}
if (aNumFetched) *aNumFetched = idx;
return S_OK;
}
STDMETHODIMP
CEnumFormatEtc::Skip(ULONG aSkipNum) {
// If the method skips the number of items requested, the return value is
// S_OK. Otherwise, it is S_FALSE.
if ((mCurrentIdx + aSkipNum) >= mFormatList.Length()) return S_FALSE;
mCurrentIdx += aSkipNum;
return S_OK;
}
STDMETHODIMP
CEnumFormatEtc::Reset(void) {
mCurrentIdx = 0;
return S_OK;
}
STDMETHODIMP
CEnumFormatEtc::Clone(LPENUMFORMATETC* aResult) {
// Must return a new IEnumFORMATETC interface with the same iterative state.
if (!aResult) return E_INVALIDARG;
CEnumFormatEtc* pEnumObj = new CEnumFormatEtc(mFormatList);
if (!pEnumObj) return E_OUTOFMEMORY;
pEnumObj->AddRef();
pEnumObj->SetIndex(mCurrentIdx);
*aResult = pEnumObj;
return S_OK;
}
/* utils */
void CEnumFormatEtc::AddFormatEtc(LPFORMATETC aFormat) {
if (!aFormat) return;
FormatEtc* etc = mFormatList.AppendElement();
// Make a copy of aFormat
if (etc) etc->CopyIn(aFormat);
}
/* private */
void CEnumFormatEtc::SetIndex(uint32_t aIdx) { mCurrentIdx = aIdx; }