Source code of Windows XP (NT5)
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//
// comutil.h - Native C++ compiler COM support - BSTR, VARIANT wrappers header
//
#pragma once
//////////////////////////////////////////////////////////////////////////////
class _bstr_t;
class auto_var;
//////////////////////////////////////////////////////////////////////////////
//
// Wrapper class for VARIANT
//
//////////////////////////////////////////////////////////////////////////////
/*
* VARENUM usage key,
*
* * [V] - may appear in a VARIANT
* * [T] - may appear in a TYPEDESC
* * [P] - may appear in an OLE property set
* * [S] - may appear in a Safe Array
* * [C] - supported by class auto_var
*
*
* VT_EMPTY [V] [P] nothing
* VT_NULL [V] [P] SQL style Null
* VT_I2 [V][T][P][S][C] 2 byte signed int
* VT_I4 [V][T][P][S][C] 4 byte signed int
* VT_R4 [V][T][P][S][C] 4 byte real
* VT_R8 [V][T][P][S][C] 8 byte real
* VT_CY [V][T][P][S][C] currency
* VT_DATE [V][T][P][S][C] date
* VT_BSTR [V][T][P][S][C] OLE Automation string
* VT_DISPATCH [V][T][P][S][C] IDispatch *
* VT_ERROR [V][T] [S][C] SCODE
* VT_BOOL [V][T][P][S][C] True=-1, False=0
* VT_VARIANT [V][T][P][S] VARIANT *
* VT_UNKNOWN [V][T] [S][C] IUnknown *
* VT_DECIMAL [V][T] [S][C] 16 byte fixed point
* VT_I1 [T] signed char
* VT_UI1 [V][T][P][S][C] unsigned char
* VT_UI2 [T][P] unsigned short
* VT_UI4 [T][P] unsigned short
* VT_I8 [T][P] signed 64-bit int
* VT_UI8 [T][P] unsigned 64-bit int
* VT_INT [T] signed machine int
* VT_UINT [T] unsigned machine int
* VT_VOID [T] C style void
* VT_HRESULT [T] Standard return type
* VT_PTR [T] pointer type
* VT_SAFEARRAY [T] (use VT_ARRAY in VARIANT)
* VT_CARRAY [T] C style array
* VT_USERDEFINED [T] user defined type
* VT_LPSTR [T][P] null terminated string
* VT_LPWSTR [T][P] wide null terminated string
* VT_FILETIME [P] FILETIME
* VT_BLOB [P] Length prefixed bytes
* VT_STREAM [P] Name of the stream follows
* VT_STORAGE [P] Name of the storage follows
* VT_STREAMED_OBJECT [P] Stream contains an object
* VT_STORED_OBJECT [P] Storage contains an object
* VT_BLOB_OBJECT [P] Blob contains an object
* VT_CF [P] Clipboard format
* VT_CLSID [P] A Class ID
* VT_VECTOR [P] simple counted array
* VT_ARRAY [V] SAFEARRAY*
* VT_BYREF [V] void* for local use
*/
class auto_var : public ::tagVARIANT {
public:
// Constructors
//
auto_var() throw();
auto_var(const VARIANT& varSrc) throw(_com_error);
auto_var(const VARIANT* pSrc) throw(_com_error);
auto_var(const auto_var& varSrc) throw(_com_error);
auto_var(VARIANT& varSrc, bool fCopy) throw(_com_error); // Attach VARIANT if !fCopy
auto_var(short sSrc, VARTYPE vtSrc = VT_I2) throw(_com_error); // Creates a VT_I2, or a VT_BOOL
auto_var(long lSrc, VARTYPE vtSrc = VT_I4) throw(_com_error); // Creates a VT_I4, a VT_ERROR, or a VT_BOOL
auto_var(float fltSrc) throw(); // Creates a VT_R4
auto_var(double dblSrc, VARTYPE vtSrc = VT_R8) throw(_com_error); // Creates a VT_R8, or a VT_DATE
auto_var(const CY& cySrc) throw(); // Creates a VT_CY
auto_var(const _bstr_t& bstrSrc) throw(_com_error); // Creates a VT_BSTR
auto_var(const wchar_t *pSrc) throw(_com_error); // Creates a VT_BSTR
auto_var(const char* pSrc) throw(_com_error); // Creates a VT_BSTR
auto_var(IDispatch* pSrc, bool fAddRef = true) throw(); // Creates a VT_DISPATCH
auto_var(bool bSrc) throw(); // Creates a VT_BOOL
auto_var(IUnknown* pSrc, bool fAddRef = true) throw(); // Creates a VT_UNKNOWN
auto_var(const DECIMAL& decSrc) throw(); // Creates a VT_DECIMAL
auto_var(BYTE bSrc) throw(); // Creates a VT_UI1
// Destructor
//
~auto_var() throw(_com_error);
// Extractors
//
operator short() const throw(_com_error); // Extracts a short from a VT_I2
operator long() const throw(_com_error); // Extracts a long from a VT_I4
operator float() const throw(_com_error); // Extracts a float from a VT_R4
operator double() const throw(_com_error); // Extracts a double from a VT_R8
operator CY() const throw(_com_error); // Extracts a CY from a VT_CY
operator _bstr_t() const throw(_com_error); // Extracts a _bstr_t from a VT_BSTR
operator IDispatch*() const throw(_com_error); // Extracts a IDispatch* from a VT_DISPATCH
operator bool() const throw(_com_error); // Extracts a bool from a VT_BOOL
operator IUnknown*() const throw(_com_error); // Extracts a IUnknown* from a VT_UNKNOWN
operator DECIMAL() const throw(_com_error); // Extracts a DECIMAL from a VT_DECIMAL
operator BYTE() const throw(_com_error); // Extracts a BTYE (unsigned char) from a VT_UI1
// Assignment operations
//
auto_var& operator=(const VARIANT& varSrc) throw(_com_error);
auto_var& operator=(const VARIANT* pSrc) throw(_com_error);
auto_var& operator=(const auto_var& varSrc) throw(_com_error);
auto_var& operator=(short sSrc) throw(_com_error); // Assign a VT_I2, or a VT_BOOL
auto_var& operator=(long lSrc) throw(_com_error); // Assign a VT_I4, a VT_ERROR or a VT_BOOL
auto_var& operator=(float fltSrc) throw(_com_error); // Assign a VT_R4
auto_var& operator=(double dblSrc) throw(_com_error); // Assign a VT_R8, or a VT_DATE
auto_var& operator=(const CY& cySrc) throw(_com_error); // Assign a VT_CY
auto_var& operator=(const _bstr_t& bstrSrc) throw(_com_error); // Assign a VT_BSTR
auto_var& operator=(const wchar_t* pSrc) throw(_com_error); // Assign a VT_BSTR
auto_var& operator=(const char* pSrc) throw(_com_error); // Assign a VT_BSTR
auto_var& operator=(IDispatch* pSrc) throw(_com_error); // Assign a VT_DISPATCH
auto_var& operator=(bool bSrc) throw(_com_error); // Assign a VT_BOOL
auto_var& operator=(IUnknown* pSrc) throw(_com_error); // Assign a VT_UNKNOWN
auto_var& operator=(const DECIMAL& decSrc) throw(_com_error); // Assign a VT_DECIMAL
auto_var& operator=(BYTE bSrc) throw(_com_error); // Assign a VT_UI1
// Comparison operations
//
bool operator==(const VARIANT& varSrc) const throw(_com_error);
bool operator==(const VARIANT* pSrc) const throw(_com_error);
bool operator!=(const VARIANT& varSrc) const throw(_com_error);
bool operator!=(const VARIANT* pSrc) const throw(_com_error);
// Low-level operations
//
void Clear() throw(_com_error);
void Attach(VARIANT& varSrc) throw(_com_error);
VARIANT Detach() throw(_com_error);
void ChangeType(VARTYPE vartype, const auto_var* pSrc = NULL) throw(_com_error);
void SetString(const char* pSrc) throw(_com_error); // used to set ANSI string
};
//////////////////////////////////////////////////////////////////////////////////////////
//
// Constructors
//
//////////////////////////////////////////////////////////////////////////////////////////
// Default constructor
//
inline auto_var::auto_var() throw()
{
::VariantInit(this);
}
// Construct a auto_var from a const VARIANT&
//
inline auto_var::auto_var(const VARIANT& varSrc) throw(_com_error)
{
::VariantInit(this);
_com_util::CheckError(::VariantCopy(this, const_cast<VARIANT*>(&varSrc)));
}
// Construct a auto_var from a const VARIANT*
//
inline auto_var::auto_var(const VARIANT* pSrc) throw(_com_error)
{
::VariantInit(this);
_com_util::CheckError(::VariantCopy(this, const_cast<VARIANT*>(pSrc)));
}
// Construct a auto_var from a const auto_var&
//
inline auto_var::auto_var(const auto_var& varSrc) throw(_com_error)
{
::VariantInit(this);
_com_util::CheckError(::VariantCopy(this, const_cast<VARIANT*>(static_cast<const VARIANT*>(&varSrc))));
}
// Construct a auto_var from a VARIANT&. If fCopy is FALSE, give control of
// data to the auto_var without doing a VariantCopy.
//
inline auto_var::auto_var(VARIANT& varSrc, bool fCopy) throw(_com_error)
{
if (fCopy) {
::VariantInit(this);
_com_util::CheckError(::VariantCopy(this, &varSrc));
} else {
memcpy(this, &varSrc, sizeof(varSrc));
V_VT(&varSrc) = VT_EMPTY;
}
}
// Construct either a VT_I2 VARIANT or a VT_BOOL VARIANT from
// a short (the default is VT_I2)
//
inline auto_var::auto_var(short sSrc, VARTYPE vtSrc) throw(_com_error)
{
if ((vtSrc != VT_I2) && (vtSrc != VT_BOOL)) {
_com_issue_error(E_INVALIDARG);
}
if (vtSrc == VT_BOOL) {
V_VT(this) = VT_BOOL;
V_BOOL(this) = (sSrc ? VARIANT_TRUE : VARIANT_FALSE);
}
else {
V_VT(this) = VT_I2;
V_I2(this) = sSrc;
}
}
// Construct either a VT_I4 VARIANT, a VT_BOOL VARIANT, or a
// VT_ERROR VARIANT from a long (the default is VT_I4)
//
inline auto_var::auto_var(long lSrc, VARTYPE vtSrc) throw(_com_error)
{
if ((vtSrc != VT_I4) && (vtSrc != VT_ERROR) && (vtSrc != VT_BOOL)) {
_com_issue_error(E_INVALIDARG);
}
if (vtSrc == VT_ERROR) {
V_VT(this) = VT_ERROR;
V_ERROR(this) = lSrc;
}
else if (vtSrc == VT_BOOL) {
V_VT(this) = VT_BOOL;
V_BOOL(this) = (lSrc ? VARIANT_TRUE : VARIANT_FALSE);
}
else {
V_VT(this) = VT_I4;
V_I4(this) = lSrc;
}
}
// Construct a VT_R4 VARIANT from a float
//
inline auto_var::auto_var(float fltSrc) throw()
{
V_VT(this) = VT_R4;
V_R4(this) = fltSrc;
}
// Construct either a VT_R8 VARIANT, or a VT_DATE VARIANT from
// a double (the default is VT_R8)
//
inline auto_var::auto_var(double dblSrc, VARTYPE vtSrc) throw(_com_error)
{
if ((vtSrc != VT_R8) && (vtSrc != VT_DATE)) {
_com_issue_error(E_INVALIDARG);
}
if (vtSrc == VT_DATE) {
V_VT(this) = VT_DATE;
V_DATE(this) = dblSrc;
}
else {
V_VT(this) = VT_R8;
V_R8(this) = dblSrc;
}
}
// Construct a VT_CY from a CY
//
inline auto_var::auto_var(const CY& cySrc) throw()
{
V_VT(this) = VT_CY;
V_CY(this) = cySrc;
}
// Construct a VT_BSTR VARIANT from a const _bstr_t&
//
inline auto_var::auto_var(const _bstr_t& bstrSrc) throw(_com_error)
{
V_VT(this) = VT_BSTR;
BSTR bstr = static_cast<wchar_t*>(bstrSrc);
V_BSTR(this) = ::SysAllocStringByteLen(reinterpret_cast<char*>(bstr),
::SysStringByteLen(bstr));
if (V_BSTR(this) == NULL) {
_com_issue_error(E_OUTOFMEMORY);
}
}
// Construct a VT_BSTR VARIANT from a const wchar_t*
//
inline auto_var::auto_var(const wchar_t* pSrc) throw(_com_error)
{
V_VT(this) = VT_BSTR;
V_BSTR(this) = ::SysAllocString(pSrc);
if (V_BSTR(this) == NULL && pSrc != NULL) {
_com_issue_error(E_OUTOFMEMORY);
}
}
// Construct a VT_BSTR VARIANT from a const char*
//
inline auto_var::auto_var(const char* pSrc) throw(_com_error)
{
V_VT(this) = VT_BSTR;
V_BSTR(this) = _com_util::ConvertStringToBSTR(pSrc);
if (V_BSTR(this) == NULL && pSrc != NULL) {
_com_issue_error(E_OUTOFMEMORY);
}
}
// Construct a VT_DISPATCH VARIANT from an IDispatch*
//
inline auto_var::auto_var(IDispatch* pSrc, bool fAddRef) throw()
{
V_VT(this) = VT_DISPATCH;
V_DISPATCH(this) = pSrc;
// Need the AddRef() as VariantClear() calls Release(), unless fAddRef
// false indicates we're taking ownership
//
if (fAddRef) {
V_DISPATCH(this)->AddRef();
}
}
// Construct a VT_BOOL VARIANT from a bool
//
inline auto_var::auto_var(bool bSrc) throw()
{
V_VT(this) = VT_BOOL;
V_BOOL(this) = (bSrc ? VARIANT_TRUE : VARIANT_FALSE);
}
// Construct a VT_UNKNOWN VARIANT from an IUnknown*
//
inline auto_var::auto_var(IUnknown* pSrc, bool fAddRef) throw()
{
V_VT(this) = VT_UNKNOWN;
V_UNKNOWN(this) = pSrc;
// Need the AddRef() as VariantClear() calls Release(), unless fAddRef
// false indicates we're taking ownership
//
if (fAddRef) {
V_UNKNOWN(this)->AddRef();
}
}
// Construct a VT_DECIMAL VARIANT from a DECIMAL
//
inline auto_var::auto_var(const DECIMAL& decSrc) throw()
{
// Order is important here! Setting V_DECIMAL wipes out the entire VARIANT
//
V_DECIMAL(this) = decSrc;
V_VT(this) = VT_DECIMAL;
}
// Construct a VT_UI1 VARIANT from a BYTE (unsigned char)
//
inline auto_var::auto_var(BYTE bSrc) throw()
{
V_VT(this) = VT_UI1;
V_UI1(this) = bSrc;
}
//////////////////////////////////////////////////////////////////////////////////////////
//
// Extractors
//
//////////////////////////////////////////////////////////////////////////////////////////
// Extracts a VT_I2 into a short
//
inline auto_var::operator short() const throw(_com_error)
{
if (V_VT(this) == VT_I2) {
return V_I2(this);
}
auto_var varDest;
varDest.ChangeType(VT_I2, this);
return V_I2(&varDest);
}
// Extracts a VT_I4 into a long
//
inline auto_var::operator long() const throw(_com_error)
{
if (V_VT(this) == VT_I4) {
return V_I4(this);
}
auto_var varDest;
varDest.ChangeType(VT_I4, this);
return V_I4(&varDest);
}
// Extracts a VT_R4 into a float
//
inline auto_var::operator float() const throw(_com_error)
{
if (V_VT(this) == VT_R4) {
return V_R4(this);
}
auto_var varDest;
varDest.ChangeType(VT_R4, this);
return V_R4(&varDest);
}
// Extracts a VT_R8 into a double
//
inline auto_var::operator double() const throw(_com_error)
{
if (V_VT(this) == VT_R8) {
return V_R8(this);
}
auto_var varDest;
varDest.ChangeType(VT_R8, this);
return V_R8(&varDest);
}
// Extracts a VT_CY into a CY
//
inline auto_var::operator CY() const throw(_com_error)
{
if (V_VT(this) == VT_CY) {
return V_CY(this);
}
auto_var varDest;
varDest.ChangeType(VT_CY, this);
return V_CY(&varDest);
}
// Extracts a VT_BSTR into a _bstr_t
//
inline auto_var::operator _bstr_t() const throw(_com_error)
{
if (V_VT(this) == VT_BSTR) {
return V_BSTR(this);
}
auto_var varDest;
varDest.ChangeType(VT_BSTR, this);
return V_BSTR(&varDest);
}
// Extracts a VT_DISPATCH into an IDispatch*
//
inline auto_var::operator IDispatch*() const throw(_com_error)
{
if (V_VT(this) == VT_DISPATCH) {
V_DISPATCH(this)->AddRef();
return V_DISPATCH(this);
}
auto_var varDest;
varDest.ChangeType(VT_DISPATCH, this);
V_DISPATCH(&varDest)->AddRef();
return V_DISPATCH(&varDest);
}
// Extract a VT_BOOL into a bool
//
inline auto_var::operator bool() const throw(_com_error)
{
if (V_VT(this) == VT_BOOL) {
return V_BOOL(this) ? true : false;
}
auto_var varDest;
varDest.ChangeType(VT_BOOL, this);
return V_BOOL(&varDest) ? true : false;
}
// Extracts a VT_UNKNOWN into an IUnknown*
//
inline auto_var::operator IUnknown*() const throw(_com_error)
{
if (V_VT(this) == VT_UNKNOWN) {
return V_UNKNOWN(this);
}
auto_var varDest;
varDest.ChangeType(VT_UNKNOWN, this);
return V_UNKNOWN(&varDest);
}
// Extracts a VT_DECIMAL into a DECIMAL
//
inline auto_var::operator DECIMAL() const throw(_com_error)
{
if (V_VT(this) == VT_DECIMAL) {
return V_DECIMAL(this);
}
auto_var varDest;
varDest.ChangeType(VT_DECIMAL, this);
return V_DECIMAL(&varDest);
}
// Extracts a VT_UI1 into a BYTE (unsigned char)
//
inline auto_var::operator BYTE() const throw(_com_error)
{
if (V_VT(this) == VT_UI1) {
return V_UI1(this);
}
auto_var varDest;
varDest.ChangeType(VT_UI1, this);
return V_UI1(&varDest);
}
//////////////////////////////////////////////////////////////////////////////////////////
//
// Assignment operations
//
//////////////////////////////////////////////////////////////////////////////////////////
// Assign a const VARIANT& (::VariantCopy handles everything)
//
inline auto_var& auto_var::operator=(const VARIANT& varSrc) throw(_com_error)
{
Clear();
_com_util::CheckError(::VariantCopy(this, const_cast<VARIANT*>(&varSrc)));
return *this;
}
// Assign a const VARIANT* (::VariantCopy handles everything)
//
inline auto_var& auto_var::operator=(const VARIANT* pSrc) throw(_com_error)
{
Clear();
_com_util::CheckError(::VariantCopy(this, const_cast<VARIANT*>(pSrc)));
return *this;
}
// Assign a const auto_var& (::VariantCopy handles everything)
//
inline auto_var& auto_var::operator=(const auto_var& varSrc) throw(_com_error)
{
Clear();
_com_util::CheckError(::VariantCopy(this, const_cast<VARIANT*>(static_cast<const VARIANT*>(&varSrc))));
return *this;
}
// Assign a short creating either VT_I2 VARIANT or a
// VT_BOOL VARIANT (VT_I2 is the default)
//
inline auto_var& auto_var::operator=(short sSrc) throw(_com_error)
{
if (V_VT(this) == VT_I2) {
V_I2(this) = sSrc;
}
else if (V_VT(this) == VT_BOOL) {
V_BOOL(this) = (sSrc ? VARIANT_TRUE : VARIANT_FALSE);
}
else {
// Clear the VARIANT and create a VT_I2
//
Clear();
V_VT(this) = VT_I2;
V_I2(this) = sSrc;
}
return *this;
}
// Assign a long creating either VT_I4 VARIANT, a VT_ERROR VARIANT
// or a VT_BOOL VARIANT (VT_I4 is the default)
//
inline auto_var& auto_var::operator=(long lSrc) throw(_com_error)
{
if (V_VT(this) == VT_I4) {
V_I4(this) = lSrc;
}
else if (V_VT(this) == VT_ERROR) {
V_ERROR(this) = lSrc;
}
else if (V_VT(this) == VT_BOOL) {
V_BOOL(this) = (lSrc ? VARIANT_TRUE : VARIANT_FALSE);
}
else {
// Clear the VARIANT and create a VT_I4
//
Clear();
V_VT(this) = VT_I4;
V_I4(this) = lSrc;
}
return *this;
}
// Assign a float creating a VT_R4 VARIANT
//
inline auto_var& auto_var::operator=(float fltSrc) throw(_com_error)
{
if (V_VT(this) != VT_R4) {
// Clear the VARIANT and create a VT_R4
//
Clear();
V_VT(this) = VT_R4;
}
V_R4(this) = fltSrc;
return *this;
}
// Assign a double creating either a VT_R8 VARIANT, or a VT_DATE
// VARIANT (VT_R8 is the default)
//
inline auto_var& auto_var::operator=(double dblSrc) throw(_com_error)
{
if (V_VT(this) == VT_R8) {
V_R8(this) = dblSrc;
}
else if(V_VT(this) == VT_DATE) {
V_DATE(this) == dblSrc;
}
else {
// Clear the VARIANT and create a VT_R8
//
Clear();
V_VT(this) = VT_R8;
V_R8(this) = dblSrc;
}
return *this;
}
// Assign a CY creating a VT_CY VARIANT
//
inline auto_var& auto_var::operator=(const CY& cySrc) throw(_com_error)
{
if (V_VT(this) != VT_CY) {
// Clear the VARIANT and create a VT_CY
//
Clear();
V_VT(this) = VT_CY;
}
V_CY(this) = cySrc;
return *this;
}
// Assign a const _bstr_t& creating a VT_BSTR VARIANT
//
inline auto_var& auto_var::operator=(const _bstr_t& bstrSrc) throw(_com_error)
{
// Clear the VARIANT (This will SysFreeString() any previous occupant)
//
Clear();
V_VT(this) = VT_BSTR;
if (!bstrSrc) {
V_BSTR(this) = NULL;
}
else {
BSTR bstr = static_cast<wchar_t*>(bstrSrc);
V_BSTR(this) = ::SysAllocStringByteLen(reinterpret_cast<char*>(bstr),
::SysStringByteLen(bstr));
if (V_BSTR(this) == NULL) {
_com_issue_error(E_OUTOFMEMORY);
}
}
return *this;
}
// Assign a const wchar_t* creating a VT_BSTR VARIANT
//
inline auto_var& auto_var::operator=(const wchar_t* pSrc) throw(_com_error)
{
// Clear the VARIANT (This will SysFreeString() any previous occupant)
//
Clear();
V_VT(this) = VT_BSTR;
if (pSrc == NULL) {
V_BSTR(this) = NULL;
}
else {
V_BSTR(this) = ::SysAllocString(pSrc);
if (V_BSTR(this) == NULL) {
_com_issue_error(E_OUTOFMEMORY);
}
}
return *this;
}
// Assign a const char* creating a VT_BSTR VARIANT
//
inline auto_var& auto_var::operator=(const char* pSrc) throw(_com_error)
{
// Clear the VARIANT (This will SysFreeString() any previous occupant)
//
Clear();
V_VT(this) = VT_BSTR;
V_BSTR(this) = _com_util::ConvertStringToBSTR(pSrc);
if (V_BSTR(this) == NULL && pSrc != NULL) {
_com_issue_error(E_OUTOFMEMORY);
}
return *this;
}
// Assign an IDispatch* creating a VT_DISPATCH VARIANT
//
inline auto_var& auto_var::operator=(IDispatch* pSrc) throw(_com_error)
{
// Clear the VARIANT (This will Release() any previous occupant)
//
Clear();
V_VT(this) = VT_DISPATCH;
V_DISPATCH(this) = pSrc;
// Need the AddRef() as VariantClear() calls Release()
//
V_DISPATCH(this)->AddRef();
return *this;
}
// Assign a bool creating a VT_BOOL VARIANT
//
inline auto_var& auto_var::operator=(bool bSrc) throw(_com_error)
{
if (V_VT(this) != VT_BOOL) {
// Clear the VARIANT and create a VT_BOOL
//
Clear();
V_VT(this) = VT_BOOL;
}
V_BOOL(this) = (bSrc ? VARIANT_TRUE : VARIANT_FALSE);
return *this;
}
// Assign an IUnknown* creating a VT_UNKNOWN VARIANT
//
inline auto_var& auto_var::operator=(IUnknown* pSrc) throw(_com_error)
{
// Clear VARIANT (This will Release() any previous occupant)
//
Clear();
V_VT(this) = VT_UNKNOWN;
V_UNKNOWN(this) = pSrc;
// Need the AddRef() as VariantClear() calls Release()
//
V_UNKNOWN(this)->AddRef();
return *this;
}
// Assign a DECIMAL creating a VT_DECIMAL VARIANT
//
inline auto_var& auto_var::operator=(const DECIMAL& decSrc) throw(_com_error)
{
if (V_VT(this) != VT_DECIMAL) {
// Clear the VARIANT
//
Clear();
}
// Order is important here! Setting V_DECIMAL wipes out the entire VARIANT
V_DECIMAL(this) = decSrc;
V_VT(this) = VT_DECIMAL;
return *this;
}
// Assign a BTYE (unsigned char) creating a VT_UI1 VARIANT
//
inline auto_var& auto_var::operator=(BYTE bSrc) throw(_com_error)
{
if (V_VT(this) != VT_UI1) {
// Clear the VARIANT and create a VT_UI1
//
Clear();
V_VT(this) = VT_UI1;
}
V_UI1(this) = bSrc;
return *this;
}
//////////////////////////////////////////////////////////////////////////////////////////
//
// Comparison operations
//
//////////////////////////////////////////////////////////////////////////////////////////
// Compare a auto_var against a const VARIANT& for equality
//
inline bool auto_var::operator==(const VARIANT& varSrc) const throw()
{
return *this == &varSrc;
}
// Compare a auto_var against a const VARIANT* for equality
//
inline bool auto_var::operator==(const VARIANT* pSrc) const throw()
{
if (this == pSrc) {
return true;
}
//
// Variants not equal if types don't match
//
if (V_VT(this) != V_VT(pSrc)) {
return false;
}
//
// Check type specific values
//
switch (V_VT(this)) {
case VT_EMPTY:
case VT_NULL:
return true;
case VT_I2:
return V_I2(this) == V_I2(pSrc);
case VT_I4:
return V_I4(this) == V_I4(pSrc);
case VT_R4:
return V_R4(this) == V_R4(pSrc);
case VT_R8:
return V_R8(this) == V_R8(pSrc);
case VT_CY:
return memcmp(&(V_CY(this)), &(V_CY(pSrc)), sizeof(CY)) == 0;
case VT_DATE:
return V_DATE(this) == V_DATE(pSrc);
case VT_BSTR:
return (::SysStringByteLen(V_BSTR(this)) == ::SysStringByteLen(V_BSTR(pSrc))) &&
(memcmp(V_BSTR(this), V_BSTR(pSrc), ::SysStringByteLen(V_BSTR(this))) == 0);
case VT_DISPATCH:
return V_DISPATCH(this) == V_DISPATCH(pSrc);
case VT_ERROR:
return V_ERROR(this) == V_ERROR(pSrc);
case VT_BOOL:
return V_BOOL(this) == V_BOOL(pSrc);
case VT_UNKNOWN:
return V_UNKNOWN(this) == V_UNKNOWN(pSrc);
case VT_DECIMAL:
return memcmp(&(V_DECIMAL(this)), &(V_DECIMAL(pSrc)), sizeof(DECIMAL)) == 0;
case VT_UI1:
return V_UI1(this) == V_UI1(pSrc);
default:
_com_issue_error(E_INVALIDARG);
// fall through
}
return false;
}
// Compare a auto_var against a const VARIANT& for in-equality
//
inline bool auto_var::operator!=(const VARIANT& varSrc) const throw()
{
return !(*this == &varSrc);
}
// Compare a auto_var against a const VARIANT* for in-equality
//
inline bool auto_var::operator!=(const VARIANT* pSrc) const throw()
{
return !(*this == pSrc);
}
//////////////////////////////////////////////////////////////////////////////////////////
//
// Low-level operations
//
//////////////////////////////////////////////////////////////////////////////////////////
// Clear the auto_var
//
inline void auto_var::Clear() throw(_com_error)
{
_com_util::CheckError(::VariantClear(this));
}
inline void auto_var::Attach(VARIANT& varSrc) throw(_com_error)
{
//
// Free up previous VARIANT
//
Clear();
//
// Give control of data to auto_var
//
memcpy(this, &varSrc, sizeof(varSrc));
V_VT(&varSrc) = VT_EMPTY;
}
inline VARIANT auto_var::Detach() throw(_com_error)
{
VARIANT varResult = *this;
V_VT(this) = VT_EMPTY;
return varResult;
}
// Change the type and contents of this auto_var to the type vartype and
// contents of pSrc
//
inline void auto_var::ChangeType(VARTYPE vartype, const auto_var* pSrc) throw(_com_error)
{
//
// If pDest is NULL, convert type in place
//
if (pSrc == NULL) {
pSrc = this;
}
if ((this != pSrc) || (vartype != V_VT(this))) {
_com_util::CheckError(::VariantChangeType(static_cast<VARIANT*>(this),
const_cast<VARIANT*>(static_cast<const VARIANT*>(pSrc)),
0, vartype));
}
}
inline void auto_var::SetString(const char* pSrc) throw(_com_error)
{
//
// Free up previous VARIANT
//
Clear();
V_VT(this) = VT_BSTR;
V_BSTR(this) = _com_util::ConvertStringToBSTR(pSrc);
if (V_BSTR(this) == NULL && pSrc != NULL) {
_com_issue_error(E_OUTOFMEMORY);
}
}
//////////////////////////////////////////////////////////////////////////////////////////
//
// Destructor
//
//////////////////////////////////////////////////////////////////////////////////////////
inline auto_var::~auto_var() throw(_com_error)
{
_com_util::CheckError(::VariantClear(this));
}