ClickHouse/src/Functions/filesystem.cpp
2020-04-03 18:14:31 +03:00

69 lines
2.1 KiB
C++

#include <Functions/IFunctionImpl.h>
#include <Functions/FunctionFactory.h>
#include <DataTypes/DataTypesNumber.h>
#include <Interpreters/Context.h>
#include <filesystem>
#include <Poco/Util/AbstractConfiguration.h>
namespace DB
{
struct FilesystemAvailable
{
static constexpr auto name = "filesystemAvailable";
static std::uintmax_t get(std::filesystem::space_info & spaceinfo) { return spaceinfo.available; }
};
struct FilesystemFree
{
static constexpr auto name = "filesystemFree";
static std::uintmax_t get(std::filesystem::space_info & spaceinfo) { return spaceinfo.free; }
};
struct FilesystemCapacity
{
static constexpr auto name = "filesystemCapacity";
static std::uintmax_t get(std::filesystem::space_info & spaceinfo) { return spaceinfo.capacity; }
};
template <typename Impl>
class FilesystemImpl : public IFunction
{
public:
static constexpr auto name = Impl::name;
static FunctionPtr create(const Context & context)
{
return std::make_shared<FilesystemImpl<Impl>>(std::filesystem::space(context.getConfigRef().getString("path")));
}
explicit FilesystemImpl(std::filesystem::space_info spaceinfo_) : spaceinfo(spaceinfo_) { }
String getName() const override { return name; }
size_t getNumberOfArguments() const override { return 0; }
bool isDeterministic() const override { return false; }
DataTypePtr getReturnTypeImpl(const DataTypes & /*arguments*/) const override
{
return std::make_shared<DataTypeUInt64>();
}
void executeImpl(Block & block, const ColumnNumbers &, size_t result, size_t input_rows_count) override
{
block.getByPosition(result).column = DataTypeUInt64().createColumnConst(input_rows_count, static_cast<UInt64>(Impl::get(spaceinfo)));
}
private:
std::filesystem::space_info spaceinfo;
};
void registerFunctionFilesystem(FunctionFactory & factory)
{
factory.registerFunction<FilesystemImpl<FilesystemAvailable>>();
factory.registerFunction<FilesystemImpl<FilesystemCapacity>>();
factory.registerFunction<FilesystemImpl<FilesystemFree>>();
}
}