/*-
 * Copyright (c) 2006,2008-2010 Joseph Koshy
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $Id: libelf.h,v 1.1 2019/02/01 05:27:38 jsg Exp $
 */

#ifndef _LIBELF_H_
#define _LIBELF_H_

#include <sys/types.h>

#include <sys/exec_elf.h>

/* Non-standard public data structures */

/* Capability */
typedef struct {
        Elf32_Word      c_tag;
        union {
                Elf32_Word      c_val;
                Elf32_Addr      c_ptr;
        } c_un;
} Elf32_Cap;

typedef struct {
        Elf64_Xword     c_tag;
        union {
                Elf64_Xword     c_val;
                Elf64_Addr      c_ptr;
        } c_un;
} Elf64_Cap;

/* Move */
typedef struct {
        Elf32_Lword     m_value;
        Elf32_Word      m_info;
        Elf32_Word      m_poffset;
        Elf32_Half      m_repeat;
        Elf32_Half      m_stride;
} Elf32_Move;

typedef struct {
        Elf64_Lword     m_value;
        Elf64_Xword     m_info;
        Elf64_Xword     m_poffset;
        Elf64_Half      m_repeat;
        Elf64_Half      m_stride;
} Elf64_Move;

/* Syminfo Table */
typedef struct {
        Elf32_Half      si_boundto;
        Elf32_Half      si_flags;
} Elf32_Syminfo;

typedef struct {
        Elf64_Half      si_boundto;
        Elf64_Half      si_flags;
} Elf64_Syminfo;

/* Version Definition */
typedef struct {
        Elf32_Half      vd_version;
        Elf32_Half      vd_flags;
        Elf32_Half      vd_ndx;
        Elf32_Half      vd_cnt;
        Elf32_Word      vd_hash;
        Elf32_Word      vd_aux;
        Elf32_Word      vd_next;
} Elf32_Verdef;

typedef struct {
        Elf32_Word      vda_name;
        Elf32_Word      vda_next;
} Elf32_Verdaux;

typedef struct {
        Elf64_Half      vd_version;
        Elf64_Half      vd_flags;
        Elf64_Half      vd_ndx;
        Elf64_Half      vd_cnt;
        Elf64_Word      vd_hash;
        Elf64_Word      vd_aux;
        Elf64_Word      vd_next;
} Elf64_Verdef;

typedef struct {
        Elf64_Word      vda_name;
        Elf64_Word      vda_next;
} Elf64_Verdaux;

/* Version Dependency */

typedef struct {
        Elf32_Half      vn_version;
        Elf32_Half      vn_cnt;
        Elf32_Word      vn_file;
        Elf32_Word      vn_aux;
        Elf32_Word      vn_next;
} Elf32_Verneed;

typedef struct {
        Elf32_Word      vna_hash;
        Elf32_Half      vna_flags;
        Elf32_Half      vna_other;
        Elf32_Word      vna_name;
        Elf32_Word      vna_next;
} Elf32_Vernaux;

typedef struct {
        Elf64_Half      vn_version;
        Elf64_Half      vn_cnt;
        Elf64_Word      vn_file;
        Elf64_Word      vn_aux;
        Elf64_Word      vn_next;
} Elf64_Verneed;

typedef struct {
        Elf64_Word      vna_hash;
        Elf64_Half      vna_flags;
        Elf64_Half      vna_other;
        Elf64_Word      vna_name;
        Elf64_Word      vna_next;
} Elf64_Vernaux;

/* GNU-style hash sections */
typedef struct {
        uint32_t        gh_nbuckets;    /* Number of hash buckets. */
        uint32_t        gh_symndx;      /* First visible symbol in .dynsym. */
        uint32_t        gh_maskwords;   /* #maskwords used in bloom filter. */
        uint32_t        gh_shift2;      /* Bloom filter shift count. */
} Elf_GNU_Hash_Header;

/* Library private data structures */
typedef struct _Elf Elf;
typedef struct _Elf_Scn Elf_Scn;

/* File types */
typedef enum {
        ELF_K_NONE = 0,
        ELF_K_AR,       /* `ar' archives */
        ELF_K_COFF,     /* COFF files (unsupported) */
        ELF_K_ELF,      /* ELF files */
        ELF_K_NUM
} Elf_Kind;

#define ELF_K_FIRST     ELF_K_NONE
#define ELF_K_LAST      ELF_K_NUM

/* Data types */
typedef enum {
        ELF_T_ADDR,
        ELF_T_BYTE,
        ELF_T_CAP,
        ELF_T_DYN,
        ELF_T_EHDR,
        ELF_T_HALF,
        ELF_T_LWORD,
        ELF_T_MOVE,
        ELF_T_MOVEP,
        ELF_T_NOTE,
        ELF_T_OFF,
        ELF_T_PHDR,
        ELF_T_REL,
        ELF_T_RELA,
        ELF_T_SHDR,
        ELF_T_SWORD,
        ELF_T_SXWORD,
        ELF_T_SYMINFO,
        ELF_T_SYM,
        ELF_T_VDEF,
        ELF_T_VNEED,
        ELF_T_WORD,
        ELF_T_XWORD,
        ELF_T_GNUHASH,  /* GNU style hash tables. */
        ELF_T_NUM
} Elf_Type;

#define ELF_T_FIRST     ELF_T_ADDR
#define ELF_T_LAST      ELF_T_GNUHASH

/* Commands */
typedef enum {
        ELF_C_NULL = 0,
        ELF_C_CLR,
        ELF_C_FDDONE,
        ELF_C_FDREAD,
        ELF_C_RDWR,
        ELF_C_READ,
        ELF_C_SET,
        ELF_C_WRITE,
        ELF_C_NUM
} Elf_Cmd;

#define ELF_C_FIRST     ELF_C_NULL
#define ELF_C_LAST      ELF_C_NUM

/*
 * An `Elf_Data' structure describes data in an
 * ELF section.
 */
typedef struct _Elf_Data {
        /*
         * `Public' members that are part of the ELF(3) API.
         */
        uint64_t        d_align;
        void            *d_buf;
        uint64_t        d_off;
        uint64_t        d_size;
        Elf_Type        d_type;
        unsigned int    d_version;
} Elf_Data;

/*
 * An `Elf_Arhdr' structure describes an archive
 * header.
 */
typedef struct {
        time_t          ar_date;
        char            *ar_name;       /* archive member name */
        gid_t           ar_gid;
        mode_t          ar_mode;
        char            *ar_rawname;    /* 'raw' member name */
        size_t          ar_size;
        uid_t           ar_uid;

        /*
         * Members that are not part of the public API.
         */
        unsigned int    ar_flags;
} Elf_Arhdr;

/*
 * An `Elf_Arsym' describes an entry in the archive
 * symbol table.
 */
typedef struct {
        off_t           as_off;         /* byte offset to member's header */
        unsigned long   as_hash;        /* elf_hash() value for name */
        char            *as_name;       /* null terminated symbol name */
} Elf_Arsym;

/*
 * Error numbers.
 */

enum Elf_Error {
        ELF_E_NONE,     /* No error */
        ELF_E_ARCHIVE,  /* Malformed ar(1) archive */
        ELF_E_ARGUMENT, /* Invalid argument */
        ELF_E_CLASS,    /* Mismatched ELF class */
        ELF_E_DATA,     /* Invalid data descriptor */
        ELF_E_HEADER,   /* Missing or malformed ELF header */
        ELF_E_IO,       /* I/O error */
        ELF_E_LAYOUT,   /* Layout constraint violation */
        ELF_E_MODE,     /* Wrong mode for ELF descriptor */
        ELF_E_RANGE,    /* Value out of range */
        ELF_E_RESOURCE, /* Resource exhaustion */
        ELF_E_SECTION,  /* Invalid section descriptor */
        ELF_E_SEQUENCE, /* API calls out of sequence */
        ELF_E_UNIMPL,   /* Feature is unimplemented */
        ELF_E_VERSION,  /* Unknown API version */
        ELF_E_NUM       /* Max error number */
};

/*
 * Flags defined by the API.
 */

#define ELF_F_LAYOUT    0x001U  /* application will layout the file */
#define ELF_F_DIRTY     0x002U  /* a section or ELF file is dirty */

/* ELF(3) API extensions. */
#define ELF_F_ARCHIVE      0x100U /* archive creation */
#define ELF_F_ARCHIVE_SYSV 0x200U /* SYSV style archive */

#ifdef __cplusplus
extern "C" {
#endif
Elf             *elf_begin(int _fd, Elf_Cmd _cmd, Elf *_elf);
int             elf_cntl(Elf *_elf, Elf_Cmd _cmd);
int             elf_end(Elf *_elf);
const char      *elf_errmsg(int _error);
int             elf_errno(void);
void            elf_fill(int _fill);
unsigned int    elf_flagarhdr(Elf_Arhdr *_arh, Elf_Cmd _cmd,
                        unsigned int _flags);
unsigned int    elf_flagdata(Elf_Data *_data, Elf_Cmd _cmd,
                        unsigned int _flags);
unsigned int    elf_flagehdr(Elf *_elf, Elf_Cmd _cmd, unsigned int _flags);
unsigned int    elf_flagelf(Elf *_elf, Elf_Cmd _cmd, unsigned int _flags);
unsigned int    elf_flagphdr(Elf *_elf, Elf_Cmd _cmd, unsigned int _flags);
unsigned int    elf_flagscn(Elf_Scn *_scn, Elf_Cmd _cmd, unsigned int _flags);
unsigned int    elf_flagshdr(Elf_Scn *_scn, Elf_Cmd _cmd, unsigned int _flags);
Elf_Arhdr       *elf_getarhdr(Elf *_elf);
Elf_Arsym       *elf_getarsym(Elf *_elf, size_t *_ptr);
off_t           elf_getbase(Elf *_elf);
Elf_Data        *elf_getdata(Elf_Scn *, Elf_Data *);
char            *elf_getident(Elf *_elf, size_t *_ptr);
int             elf_getphdrnum(Elf *_elf, size_t *_dst);
int             elf_getphnum(Elf *_elf, size_t *_dst);  /* Deprecated */
Elf_Scn         *elf_getscn(Elf *_elf, size_t _index);
int             elf_getshdrnum(Elf *_elf, size_t *_dst);
int             elf_getshnum(Elf *_elf, size_t *_dst);  /* Deprecated */
int             elf_getshdrstrndx(Elf *_elf, size_t *_dst);
int             elf_getshstrndx(Elf *_elf, size_t *_dst); /* Deprecated */
unsigned long   elf_hash(const char *_name);
Elf_Kind        elf_kind(Elf *_elf);
Elf             *elf_memory(char *_image, size_t _size);
size_t          elf_ndxscn(Elf_Scn *_scn);
Elf_Data        *elf_newdata(Elf_Scn *_scn);
Elf_Scn         *elf_newscn(Elf *_elf);
Elf_Scn         *elf_nextscn(Elf *_elf, Elf_Scn *_scn);
Elf_Cmd         elf_next(Elf *_elf);
Elf             *elf_open(int _fd);
Elf             *elf_openmemory(char *_image, size_t _size);
off_t           elf_rand(Elf *_elf, off_t _off);
Elf_Data        *elf_rawdata(Elf_Scn *_scn, Elf_Data *_data);
char            *elf_rawfile(Elf *_elf, size_t *_size);
int             elf_setshstrndx(Elf *_elf, size_t _shnum);
char            *elf_strptr(Elf *_elf, size_t _section, size_t _offset);
off_t           elf_update(Elf *_elf, Elf_Cmd _cmd);
unsigned int    elf_version(unsigned int _version);

long            elf32_checksum(Elf *_elf);
size_t          elf32_fsize(Elf_Type _type, size_t _count,
                        unsigned int _version);
Elf32_Ehdr      *elf32_getehdr(Elf *_elf);
Elf32_Phdr      *elf32_getphdr(Elf *_elf);
Elf32_Shdr      *elf32_getshdr(Elf_Scn *_scn);
Elf32_Ehdr      *elf32_newehdr(Elf *_elf);
Elf32_Phdr      *elf32_newphdr(Elf *_elf, size_t _count);
Elf_Data        *elf32_xlatetof(Elf_Data *_dst, const Elf_Data *_src,
                        unsigned int _enc);
Elf_Data        *elf32_xlatetom(Elf_Data *_dst, const Elf_Data *_src,
                        unsigned int _enc);

long            elf64_checksum(Elf *_elf);
size_t          elf64_fsize(Elf_Type _type, size_t _count,
                        unsigned int _version);
Elf64_Ehdr      *elf64_getehdr(Elf *_elf);
Elf64_Phdr      *elf64_getphdr(Elf *_elf);
Elf64_Shdr      *elf64_getshdr(Elf_Scn *_scn);
Elf64_Ehdr      *elf64_newehdr(Elf *_elf);
Elf64_Phdr      *elf64_newphdr(Elf *_elf, size_t _count);
Elf_Data        *elf64_xlatetof(Elf_Data *_dst, const Elf_Data *_src,
                        unsigned int _enc);
Elf_Data        *elf64_xlatetom(Elf_Data *_dst, const Elf_Data *_src,
                        unsigned int _enc);
#ifdef __cplusplus
}
#endif

#endif  /* _LIBELF_H_ */