/*
 * elf.hpp
 *
 * Copyright (C) 2005 Bastian Blank <waldi@debian.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#ifndef ELF_HPP
#define ELF_HPP

#include "elf_defs.hpp"

#include <stdexcept>
#include <string>
#include <vector>

#include <stdint.h>

namespace Elf
{
  class section;
  template <typename _type> class section_type;
  class segment;
  template <typename _type> class segment_type;

  class file
  {
    public:
      virtual ~file () throw ();

      virtual const uint8_t get_class() const throw () = 0;
      virtual const uint8_t get_data() const throw () = 0;
      const uint16_t get_type() const throw () { return type; }
      const uint16_t get_machine() const throw () { return machine; }
      const uint32_t get_flags() const throw () { return flags; }
      const uint16_t get_shstrndx() const throw () { return shstrndx; }

      const std::vector<section *> get_sections() const throw () { return sections; };
      const section &get_section(unsigned int i) const throw () { return *sections.at(i); };
      const section_type<section_type_DYNAMIC> *get_section_DYNAMIC() const throw () { return section_DYNAMIC; };
      const section_type<section_type_DYNSYM> *get_section_DYNSYM() const throw () { return section_DYNSYM; };
      const section_type<section_type_GNU_VERDEF> *get_section_GNU_VERDEF() const throw () { return section_GNU_VERDEF; };
      const section_type<section_type_GNU_VERNEED> *get_section_GNU_VERNEED() const throw () { return section_GNU_VERNEED; };
      const section_type<section_type_GNU_VERSYM> *get_section_GNU_VERSYM() const throw () { return section_GNU_VERSYM; };

      const std::vector<segment *> get_segments() const throw () { return segments; };
      const segment_type<segment_type_INTERP> *get_segment_INTERP() const throw () { return segment_INTERP; };

      static file *open(const char *filename) throw ();

    protected:
      file(uint8_t *mem, size_t len) throw () : mem(mem), len(len) { }

      template<typename _class>
        static file *open_class(uint8_t *, size_t) throw ();

      uint16_t type;
      uint16_t machine;
      uint64_t phoff;
      uint64_t shoff;
      uint32_t flags;
      uint16_t phentsize;
      uint16_t phnum;
      uint16_t shentsize;
      uint16_t shnum;
      uint16_t shstrndx;

      std::vector<section *> sections;
      section_type<section_type_DYNAMIC> *section_DYNAMIC;
      section_type<section_type_DYNSYM> *section_DYNSYM;
      section_type<section_type_GNU_VERDEF> *section_GNU_VERDEF;
      section_type<section_type_GNU_VERNEED> *section_GNU_VERNEED;
      section_type<section_type_GNU_VERSYM> *section_GNU_VERSYM;

      std::vector<segment *> segments;
      segment_type<segment_type_INTERP> *segment_INTERP;

      uint8_t *const mem;
      const size_t len;
  };

  class section
  {
    public:
      virtual ~section() throw () {}

      uint32_t get_type() const throw () { return type; }
      uint64_t get_size() const throw () { return size; }
      const std::string &get_name_string() const throw () { return name_string; }

    protected:
      uint32_t name;
      uint32_t type;
      uint64_t offset;
      uint64_t size;
      uint32_t link;

      std::string name_string;

      uint8_t *mem;
  };

  template <typename _type>
    class section_type : public virtual section
    {
    };

  class dynamic;
  class symbol;
  class version_definition;
  class version_requirement;
  class version_requirement_entry;

  template <>
    class section_type<section_type_STRTAB> : public virtual section
    {
      public:
        std::string get_string(uint32_t offset) const throw ()
        {
          return std::string(reinterpret_cast<const char *> (mem + offset));
        }
    };

  template <>
    class section_type<section_type_DYNAMIC> : public virtual section
    {
      public:
        ~section_type() throw ();

        const std::vector<dynamic *> &get_dynamics() const throw () { return dynamics; }

      protected:
        std::vector<dynamic *> dynamics;
    };

  template <>
    class section_type<section_type_DYNSYM> : public virtual section
    {
      public:
        ~section_type() throw ();

        const std::vector<symbol *> &get_symbols() const throw () { return symbols; }

      protected:
        std::vector<symbol *> symbols;
    };

  template <>
    class section_type<section_type_GNU_VERDEF> : public virtual section
    {
      public:
        ~section_type() throw () { }

        const version_definition *get_version_definition(uint16_t index) const throw ();
        const std::vector<version_definition *> &get_version_definitions() throw () { return verdefs; }

      protected:
        std::vector<version_definition *> verdefs;
    };

  template <>
    class section_type<section_type_GNU_VERNEED> : public virtual section
    {
      public:
        ~section_type() throw () { }

        const version_requirement_entry *get_version_requirement_entry(uint16_t index) const throw ();
        const std::vector<version_requirement *> &get_version_requirements() throw () { return verneeds; }

      protected:
        std::vector<version_requirement *> verneeds;
    };

  template <>
    class section_type<section_type_GNU_VERSYM> : public virtual section
    {
      public:
        ~section_type () throw () { }

        const std::vector<uint16_t> &get_versyms () const throw () { return versyms; }

      protected:
        std::vector<uint16_t> versyms;
    };

  class segment
  {
    public:
      virtual ~segment() throw () {}

      uint32_t get_type() const throw () { return type; }
      uint32_t get_flags() const throw () { return flags; }
      uint64_t get_filesz() const throw () { return filesz; }

    protected:
      uint32_t type;
      uint32_t flags;
      uint64_t offset;
      uint64_t filesz;

      uint8_t *mem;
  };

  template <typename _type>
    class segment_type : public virtual segment
    {
    };

  template <>
    class segment_type<segment_type_INTERP> : public virtual segment
    {
      public:
        ~segment_type() throw () { }

        const std::string &get_interp() const throw () { return interp; }

      protected:
        std::string interp;
    };

  class dynamic
  {
    public:
      virtual ~dynamic() throw () {}

      int64_t get_tag() const throw () { return tag; }
      uint64_t get_val() const throw () { return val; }
      uint64_t get_ptr() const throw () { return ptr; }
      const std::string &get_val_string() const throw () { return val_string; }

    protected:
      int64_t tag;
      uint64_t val;
      uint64_t ptr;
      bool is_string;

      std::string val_string;
  };

  class symbol
  {
    public:
      symbol() throw () : verdef(NULL), verneed(NULL) {}
      virtual ~symbol() throw () {}

      uint8_t get_info() const throw () { return info; }
      uint16_t get_shndx() const throw () { return shndx; }
      uint64_t get_value() const throw () { return value; }
      uint64_t get_size() const throw () { return size; }
      uint8_t get_bind () const throw () { return bind; }
      uint8_t get_type () const throw () { return type; }
      const std::string &get_name_string() const throw () { return name_string; }
      std::string get_version() const throw ();
      std::string get_version_file() const throw ();
      uint16_t get_version_data() const throw () { return versym; }
      std::string get_name_version() const throw ();

    protected:
      uint32_t name;
      uint8_t info;
      uint16_t shndx;
      uint64_t value;
      uint64_t size;
      uint8_t bind;
      uint8_t type;

      std::string name_string;

      const version_definition *verdef;
      const version_requirement_entry *verneed;
      uint16_t versym;
  };

  class version_definition
  {
    public:
      virtual ~version_definition() throw () { }

      uint16_t get_ndx() const throw () { return ndx; }
      const std::vector<std::string> &get_names() const throw () { return names_string; }

    protected:
      uint16_t ndx;

      std::vector<uint32_t> names;

      std::vector<std::string> names_string;
  };

  class version_requirement_entry;

  class version_requirement
  {
    public:
      version_requirement() throw ();
      virtual ~version_requirement () throw () { }

      const std::string &get_file() const throw () { return file_string; }
      const std::vector<version_requirement_entry *> &get_entries() const throw () { return entries; }

    protected:
      uint32_t file;

      std::string file_string;

      std::vector<version_requirement_entry *> entries;
  };

  class version_requirement_entry
  {
    public:
      version_requirement_entry(const version_requirement &) throw ();
      virtual ~version_requirement_entry() throw () { }

      uint16_t get_other() const throw () { return other; }
      const std::string &get_name() const throw () { return name_string; }

      const std::string &get_file() const throw ();

    protected:
      uint16_t flags;
      uint16_t other;
      uint32_t name;

      std::string name_string;

      const version_requirement &verneed;
  };
}

#endif