dwarfinterpret/include/DwarfInterpret.hpp

#pragma once

#include <string>
#include <memory>
#include <cstdint>

#include <dwarfpp/lib.hpp>
#include <dwarfpp/regs.hpp>
#include <dwarfpp/frame.hpp>
#include <dwarfpp/attr.hpp>
#include <dwarfpp/frame.hpp>
#include <dwarfpp/root.hpp>

#define OF_WHAT_EXCEPTION(cl_name) \
    cl_name: public WhatException { \
        public:\
            cl_name(const std::string& what): WhatException(what) {} \
            cl_name() = default; \
    }

class DwarfInterpret {
    /** Singleton class holding a Dwarf interpret.
     * Must be first instanciated with the path to the binary being run, with a
     * call to `instanciate`, and can afterwards be accessed with calls to
     * `acquire`.
     */

    public:
        class WhatException: public std::exception {
            /** Base exception for other exceptions, not supposed to be thrown
             * by itself */

            std::string what_str;

            public:
                WhatException(const std::string& what): what_str(what) {}
                WhatException(): what_str("") {}

                const char* what() const noexcept {
                    return what_str.c_str();
                }
        };


        class OF_WHAT_EXCEPTION(NotInstanciated);
        class OF_WHAT_EXCEPTION(AlreadyInstanciated);
        class OF_WHAT_EXCEPTION(ValuelessRegister);
        class OF_WHAT_EXCEPTION(NotImplemented);
        class OF_WHAT_EXCEPTION(FailedGetContext);
        class OF_WHAT_EXCEPTION(NotFound);

        typedef dwarf::core::FrameSection::register_def DwarfRegister;
        typedef std::set<std::pair<int, DwarfRegister> > DwarfRow; // FIXME

        typedef uintptr_t reg_content_t;

    private:
        //typedef std::set<std::pair<int, DwarfRegister> > DwarfRow;


    public:
        DwarfInterpret(DwarfInterpret const&) = delete;
        void operator=(DwarfInterpret const&) = delete;

        static DwarfInterpret& acquire();
        static DwarfInterpret& instanciate(const std::string& elf_path);

        int get_elf_machine() const { return elf_machine; }

        reg_content_t interpret_dw_register(
                const DwarfRow& row,
                const DwarfRegister& reg
                ) const;
        reg_content_t interpret_dw_register(
                const DwarfRow& row,
                int reg_id
                ) const;

        uintptr_t get_return_address(uintptr_t cur_pc) const;
        uintptr_t get_self_return_address() const;

        static uintptr_t get_current_pc();

    private:
        DwarfInterpret(const std::string& elf_path);

        DwarfRegister get_column(const DwarfRow& row, int column) const;
        reg_content_t get_cpu_register(int reg_id) const;

        const dwarf::core::FrameSection::fde_iterator fde_at(
                uintptr_t pc) const;
        const dwarf::core::FrameSection::cie_iterator cie_at(
                uintptr_t pc) const;
        const DwarfRow& dwarf_row_at(uintptr_t pc) const;

        uintptr_t get_caller_pc() const;


    private: // members
        static std::unique_ptr<DwarfInterpret> instance;

        dwarf::core::root_die root_die;
        int elf_machine;

        friend class std::unique_ptr<DwarfInterpret>;
};