ClickHouse/dbms/src/Functions/addressToLine.cpp

#if defined(__ELF__) && !defined(__FreeBSD__)

#include <Common/Elf.h>
#include <Common/Dwarf.h>
#include <Common/SymbolIndex.h>
#include <Common/HashTable/HashMap.h>
#include <Common/Arena.h>
#include <Columns/ColumnString.h>
#include <Columns/ColumnsNumber.h>
#include <DataTypes/DataTypeString.h>
#include <Functions/IFunction.h>
#include <Functions/FunctionHelpers.h>
#include <Functions/FunctionFactory.h>
#include <IO/WriteBufferFromArena.h>
#include <IO/WriteHelpers.h>
#include <Interpreters/Context.h>

#include <mutex>
#include <filesystem>
#include <unordered_map>


namespace DB
{

namespace ErrorCodes
{
    extern const int ILLEGAL_COLUMN;
    extern const int ILLEGAL_TYPE_OF_ARGUMENT;
    extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
    extern const int FUNCTION_NOT_ALLOWED;
}

class FunctionAddressToLine : public IFunction
{
public:
    static constexpr auto name = "addressToLine";
    static FunctionPtr create(const Context & context)
    {
        if (!context.getSettingsRef().allow_introspection_functions)
            throw Exception("Introspection functions are disabled, because setting 'allow_introspection_functions' is set to 0", ErrorCodes::FUNCTION_NOT_ALLOWED);

        return std::make_shared<FunctionAddressToLine>();
    }

    String getName() const override
    {
        return name;
    }

    size_t getNumberOfArguments() const override
    {
        return 1;
    }

    DataTypePtr getReturnTypeImpl(const ColumnsWithTypeAndName & arguments) const override
    {
        if (arguments.size() != 1)
            throw Exception("Function " + getName() + " needs exactly one argument; passed "
                + toString(arguments.size()) + ".", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);

        const auto & type = arguments[0].type;

        if (!WhichDataType(type.get()).isUInt64())
            throw Exception("The only argument for function " + getName() + " must be UInt64. Found "
                + type->getName() + " instead.", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

        return std::make_shared<DataTypeString>();
    }

    bool useDefaultImplementationForConstants() const override
    {
        return true;
    }

    void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result, size_t input_rows_count) override
    {
        const ColumnPtr & column = block.getByPosition(arguments[0]).column;
        const ColumnUInt64 * column_concrete = checkAndGetColumn<ColumnUInt64>(column.get());

        if (!column_concrete)
            throw Exception("Illegal column " + column->getName() + " of argument of function " + getName(), ErrorCodes::ILLEGAL_COLUMN);

        const typename ColumnVector<UInt64>::Container & data = column_concrete->getData();
        auto result_column = ColumnString::create();

        for (size_t i = 0; i < input_rows_count; ++i)
        {
            StringRef res_str = implCached(data[i]);
            result_column->insertData(res_str.data, res_str.size);
        }

        block.getByPosition(result).column = std::move(result_column);
    }

private:
    std::mutex mutex;
    Arena arena;
    using Map = HashMap<uintptr_t, StringRef>;
    Map map;
    std::unordered_map<std::string, Dwarf> dwarfs;

    StringRef impl(uintptr_t addr)
    {
        const SymbolIndex & symbol_index = SymbolIndex::instance();

        if (auto object = symbol_index.findObject(reinterpret_cast<const void *>(addr)))
        {
            auto dwarf_it = dwarfs.try_emplace(object->name, *object->elf).first;
            if (!std::filesystem::exists(object->name))
                return {};

            Dwarf::LocationInfo location;
            if (dwarf_it->second.findAddress(addr - uintptr_t(object->address_begin), location, Dwarf::LocationInfoMode::FAST))
            {
                const char * arena_begin = nullptr;
                WriteBufferFromArena out(arena, arena_begin);

                writeString(location.file.toString(), out);
                writeChar(':', out);
                writeIntText(location.line, out);

                StringRef out_str = out.finish();
                out_str.data = arena.insert(out_str.data, out_str.size);
                return out_str;
            }
            else
            {
                return object->name;
            }
        }
        else
            return {};
    }

    StringRef implCached(uintptr_t addr)
    {
        Map::LookupResult it;
        bool inserted;
        std::lock_guard lock(mutex);
        map.emplace(addr, it, inserted);
        if (inserted)
            *lookupResultGetMapped(it) = impl(addr);
        return *lookupResultGetMapped(it);
    }
};

void registerFunctionAddressToLine(FunctionFactory & factory)
{
    factory.registerFunction<FunctionAddressToLine>();
}

}

#endif