fastfetch/src/util/windows/wmi.hpp

#pragma once

#ifndef FF_INCLUDED_util_windows_wmi
#define FF_INCLUDED_util_windows_wmi

#ifdef __cplusplus

extern "C" {
    #include "fastfetch.h"
}

#include <initguid.h>
#include <Wbemidl.h>
#include <utility>
#include <string_view>
#include <cassert>
#include <type_traits>

enum class FFWmiNamespace {
    CIMV2,
    WMI,
    LAST,
};

struct FFWmiVariant: VARIANT {
    explicit FFWmiVariant() { VariantInit(this); }
    ~FFWmiVariant() { VariantClear(this); }

    FFWmiVariant(const FFWmiVariant&) = delete;
    FFWmiVariant(FFWmiVariant&&); // don't define it to enforce NRVO optimization

    bool hasValue() {
        return this->vt != VT_EMPTY;
    }

    explicit operator bool() {
        return this->hasValue();
    }

    template <typename T> T get()
    {
        // boolean
        if constexpr (std::is_same_v<T, bool>) {
            assert(this->vt == VT_BOOL);
            return this->boolVal != VARIANT_FALSE;
        }

        // signed
        else if constexpr (std::is_same_v<T, int8_t>) {
            assert(this->vt == VT_I1);
            return this->cVal;
        }
        else if constexpr (std::is_same_v<T, int16_t>) {
            assert(vt == VT_I2);
            return this->iVal;
        }
        else if constexpr (std::is_same_v<T, int32_t>) {
            assert(this->vt == VT_I4 || vt == VT_INT);
            return this->intVal;
        }
        else if constexpr (std::is_same_v<T, int64_t>) {
            assert(this->vt == VT_I8);
            return this->llVal;
        }

        // unsigned
        else if constexpr (std::is_same_v<T, uint8_t>) {
            assert(this->vt == VT_UI1);
            return this->bVal;
        }
        else if constexpr (std::is_same_v<T, uint16_t>) {
            assert(this->vt == VT_UI2);
            return this->uiVal;
        }
        else if constexpr (std::is_same_v<T, uint32_t>) {
            assert(this->vt == VT_UI4 || vt == VT_UINT);
            return this->uintVal;
        }
        else if constexpr (std::is_same_v<T, uint64_t>) {
            assert(this->vt == VT_UI8);
            return this->ullVal;
        }

        // decimal
        else if constexpr (std::is_same_v<T, float>) {
            assert(this->vt == VT_R4);
            return this->fltVal;
        }
        else if constexpr (std::is_same_v<T, double>) {
            assert(this->vt == VT_R8);
            return this->dblVal;
        }

        // string
        else if constexpr (std::is_same_v<T, std::string_view>) {
            assert(this->vt == VT_LPSTR);
            return this->pcVal;
        }
        else if constexpr (std::is_same_v<T, std::wstring_view>) {
            assert(this->vt == VT_BSTR || this->vt == VT_LPWSTR);
            if (this->vt == VT_LPWSTR)
                return this->bstrVal;
            else
                return { this->bstrVal, SysStringLen(this->bstrVal) };
        }

        // array signed
        else if constexpr (std::is_same_v<T, std::pair<const int8_t*, uint32_t>>) {
            assert(this->vt & VT_ARRAY);
            assert((this->vt & ~VT_ARRAY) == VT_I1);
            return std::make_pair((int8_t*)this->parray->pvData, this->parray->cDims);
        }
        else if constexpr (std::is_same_v<T, std::pair<const int16_t*, uint32_t>>) {
            assert(this->vt & VT_ARRAY);
            assert((this->vt & ~VT_ARRAY) == VT_I2);
            return std::make_pair((int16_t*)this->parray->pvData, this->parray->cDims);
        }
        else if constexpr (std::is_same_v<T, std::pair<const int32_t*, uint32_t>>) {
            assert(this->vt & VT_ARRAY);
            assert((this->vt & ~VT_ARRAY) == VT_I4);
            return std::make_pair((int32_t*)this->parray->pvData, this->parray->cDims);
        }
        else if constexpr (std::is_same_v<T, std::pair<const int64_t*, uint32_t>>) {
            assert(this->vt & VT_ARRAY);
            assert((this->vt & ~VT_ARRAY) == VT_I8);
            return std::make_pair((int64_t*)this->parray->pvData, this->parray->cDims);
        }

        // array unsigned
        else if constexpr (std::is_same_v<T, std::pair<const uint8_t*, uint32_t>>) {
            assert(this->vt & VT_ARRAY);
            assert((this->vt & ~VT_ARRAY) == VT_UI1);
            return std::make_pair((uint8_t*)this->parray->pvData, this->parray->cDims);
        }
        else if constexpr (std::is_same_v<T, std::pair<const uint16_t*, uint32_t>>) {
            assert(this->vt & VT_ARRAY);
            assert((this->vt & ~VT_ARRAY) == VT_UI2);
            return std::make_pair((uint16_t*)this->parray->pvData, this->parray->cDims);
        }
        else if constexpr (std::is_same_v<T, std::pair<const uint32_t*, uint32_t>>) {
            assert(this->vt & VT_ARRAY);
            assert((this->vt & ~VT_ARRAY) == VT_UI4);
            return std::make_pair((uint32_t*)this->parray->pvData, this->parray->cDims);
        }
        else if constexpr (std::is_same_v<T, std::pair<const uint64_t*, uint32_t>>) {
            assert(this->vt & VT_ARRAY);
            assert((this->vt & ~VT_ARRAY) == VT_UI8);
            return std::make_pair((uint64_t*)this->parray->pvData, this->parray->cDims);
        }
        else {
            assert(false && "unsupported type");
            __builtin_unreachable();
        }
    }
};

struct FFWmiRecord
{
    IWbemClassObject* obj;

    explicit FFWmiRecord(IEnumWbemClassObject* pEnumerator): obj(nullptr) {
        if(!pEnumerator) return;

        ULONG ret;
        bool ok = SUCCEEDED(pEnumerator->Next(instance.config.wmiTimeout, 1, &obj, &ret)) && ret;
        if(!ok) obj = nullptr;
    }
    FFWmiRecord(const FFWmiRecord&) = delete;
    FFWmiRecord(FFWmiRecord&& other) { *this = (FFWmiRecord&&)other; }
    ~FFWmiRecord() { if(obj) obj->Release(); }
    explicit operator bool() { return !!obj; }
    FFWmiRecord& operator =(FFWmiRecord&& other) {
        if(obj) obj->Release();
        obj = other.obj;
        other.obj = nullptr;
        return *this;
    }

    bool getString(const wchar_t* key, FFstrbuf* strbuf);
    bool getSigned(const wchar_t* key, int64_t* integer);
    bool getUnsigned(const wchar_t* key, uint64_t* integer);
    bool getReal(const wchar_t* key, double* real);
    FFWmiVariant get(const wchar_t* key) {
        FFWmiVariant result;
        obj->Get(key, 0, &result, nullptr, nullptr);
        return result;
    }
};

struct FFWmiQuery
{
    IEnumWbemClassObject* pEnumerator = nullptr;

    FFWmiQuery(const wchar_t* queryStr, FFstrbuf* error = nullptr, FFWmiNamespace wmiNs = FFWmiNamespace::CIMV2);
    explicit FFWmiQuery(IEnumWbemClassObject* pEnumerator): pEnumerator(pEnumerator) {}
    FFWmiQuery(const FFWmiQuery& other) = delete;
    FFWmiQuery(FFWmiQuery&& other) { *this = (FFWmiQuery&&)other; }
    ~FFWmiQuery() { if(pEnumerator) pEnumerator->Release(); }

    explicit operator bool() { return !!pEnumerator; }
    FFWmiQuery& operator =(FFWmiQuery&& other) {
        if(pEnumerator) pEnumerator->Release();
        pEnumerator = other.pEnumerator;
        other.pEnumerator = nullptr;
        return *this;
    }

    FFWmiRecord next() {
        FFWmiRecord result(pEnumerator);
        return result;
    }
};

#else
    // Win32 COM headers requires C++ compiler
    #error Must be included in C++ source file
#endif //__cplusplus

#endif //FF_INCLUDED_util_windows_wmi