97 lines
2.6 KiB
C++
97 lines
2.6 KiB
C++
// © 2018 and later: Unicode, Inc. and others.
|
|
// License & terms of use: http://www.unicode.org/copyright.html
|
|
|
|
#ifndef __CAPI_HELPER_H__
|
|
#define __CAPI_HELPER_H__
|
|
|
|
#include "unicode/utypes.h"
|
|
|
|
U_NAMESPACE_BEGIN
|
|
|
|
/**
|
|
* An internal helper class to help convert between C and C++ APIs.
|
|
*/
|
|
template<typename CType, typename CPPType, int32_t kMagic>
|
|
class IcuCApiHelper {
|
|
public:
|
|
/**
|
|
* Convert from the C type to the C++ type (const version).
|
|
*/
|
|
static const CPPType* validate(const CType* input, UErrorCode& status);
|
|
|
|
/**
|
|
* Convert from the C type to the C++ type (non-const version).
|
|
*/
|
|
static CPPType* validate(CType* input, UErrorCode& status);
|
|
|
|
/**
|
|
* Convert from the C++ type to the C type (const version).
|
|
*/
|
|
const CType* exportConstForC() const;
|
|
|
|
/**
|
|
* Convert from the C++ type to the C type (non-const version).
|
|
*/
|
|
CType* exportForC();
|
|
|
|
/**
|
|
* Invalidates the object.
|
|
*/
|
|
~IcuCApiHelper();
|
|
|
|
private:
|
|
/**
|
|
* While the object is valid, fMagic equals kMagic.
|
|
*/
|
|
int32_t fMagic = kMagic;
|
|
};
|
|
|
|
|
|
template<typename CType, typename CPPType, int32_t kMagic>
|
|
const CPPType*
|
|
IcuCApiHelper<CType, CPPType, kMagic>::validate(const CType* input, UErrorCode& status) {
|
|
if (U_FAILURE(status)) {
|
|
return nullptr;
|
|
}
|
|
if (input == nullptr) {
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return nullptr;
|
|
}
|
|
auto* impl = reinterpret_cast<const CPPType*>(input);
|
|
if (static_cast<const IcuCApiHelper<CType, CPPType, kMagic>*>(impl)->fMagic != kMagic) {
|
|
status = U_INVALID_FORMAT_ERROR;
|
|
return nullptr;
|
|
}
|
|
return impl;
|
|
}
|
|
|
|
template<typename CType, typename CPPType, int32_t kMagic>
|
|
CPPType*
|
|
IcuCApiHelper<CType, CPPType, kMagic>::validate(CType* input, UErrorCode& status) {
|
|
auto* constInput = static_cast<const CType*>(input);
|
|
auto* validated = validate(constInput, status);
|
|
return const_cast<CPPType*>(validated);
|
|
}
|
|
|
|
template<typename CType, typename CPPType, int32_t kMagic>
|
|
const CType*
|
|
IcuCApiHelper<CType, CPPType, kMagic>::exportConstForC() const {
|
|
return reinterpret_cast<const CType*>(static_cast<const CPPType*>(this));
|
|
}
|
|
|
|
template<typename CType, typename CPPType, int32_t kMagic>
|
|
CType*
|
|
IcuCApiHelper<CType, CPPType, kMagic>::exportForC() {
|
|
return reinterpret_cast<CType*>(static_cast<CPPType*>(this));
|
|
}
|
|
|
|
template<typename CType, typename CPPType, int32_t kMagic>
|
|
IcuCApiHelper<CType, CPPType, kMagic>::~IcuCApiHelper() {
|
|
// head off application errors by preventing use of of deleted objects.
|
|
fMagic = 0;
|
|
}
|
|
|
|
|
|
U_NAMESPACE_END
|
|
|
|
#endif // __CAPI_HELPER_H__
|