/*
 * Copyright (C) 2006 Sergey Bondari
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
 */

#ifndef __ELF_H__
#define __ELF_H__

#include <arch/elf.h>
#include <arch/types.h>
#include <mm/as.h>

/**
 * current ELF version
 */
#define	EV_CURRENT	1

/** 
 * ELF types 
 */
#define ET_NONE		0	/* No type */
#define ET_REL		1	/* Relocatable file */
#define ET_EXEC		2	/* Executable */
#define ET_DYN		3	/* Shared object */
#define ET_CORE		4	/* Core */
#define ET_LOPROC	0xff00	/* Processor specific */
#define ET_HIPROC	0xffff	/* Processor specific */

/** 
 * ELF machine types
 */
#define EM_NO		0	/* No machine */
#define EM_SPARC	2	/* SPARC */
#define EM_386		3	/* i386 */
#define EM_MIPS		8	/* MIPS RS3000 */
#define EM_MIPS_RS3_LE	10	/* MIPS RS3000 LE */
#define EM_PPC		20	/* PPC32 */
#define EM_PPC64	21	/* PPC64 */
#define EM_SPARCV9	43	/* SPARC64 */
#define EM_IA_64	50	/* IA-64 */
#define EM_X86_64	62	/* AMD64/EMT64 */

/**
 * ELF identification indexes
 */
#define EI_MAG0		0
#define EI_MAG1		1
#define EI_MAG2		2
#define EI_MAG3		3
#define EI_CLASS	4		/* File class */
#define EI_DATA		5		/* Data encoding */
#define EI_VERSION	6		/* File version */
#define EI_OSABI	7
#define EI_ABIVERSION	8
#define EI_PAD		9		/* Start of padding bytes */
#define EI_NIDENT	16		/* ELF identification table size */

/**
 * ELF magic number
 */
#define ELFMAG0		0x7f
#define ELFMAG1		'E'
#define ELFMAG2		'L'
#define ELFMAG3		'F'

/**
 * ELF file classes
 */
#define ELFCLASSNONE	0
#define ELFCLASS32	1
#define ELFCLASS64	2

/**
 * ELF data encoding types
 */
#define ELFDATANONE	0
#define ELFDATA2LSB	1		/* Least significant byte first (little endian) */
#define ELFDATA2MSB	2		/* Most signigicant byte first (big endian) */

/**
 * ELF error return codes
 */
#define EE_OK			0	/* No error */
#define EE_INVALID		1	/* Invalid ELF image */
#define	EE_MEMORY		2	/* Cannot allocate address space */
#define EE_INCOMPATIBLE		3	/* ELF image is not compatible with current architecture */
#define EE_UNSUPPORTED		4	/* Non-supported ELF (e.g. dynamic ELFs) */
#define EE_IRRECOVERABLE	5

/**
 * ELF section types
 */
#define SHT_NULL		0
#define SHT_PROGBITS		1
#define SHT_SYMTAB		2
#define SHT_STRTAB		3
#define SHT_RELA		4
#define SHT_HASH		5
#define SHT_DYNAMIC		6
#define SHT_NOTE		7
#define SHT_NOBITS		8
#define SHT_REL			9
#define SHT_SHLIB		10
#define SHT_DYNSYM		11
#define SHT_LOOS		0x60000000
#define SHT_HIOS		0x6fffffff
#define SHT_LOPROC		0x70000000
#define SHT_HIPROC		0x7fffffff
#define SHT_LOUSER		0x80000000
#define SHT_HIUSER		0xffffffff

/**
 * ELF section flags
 */
#define SHF_WRITE		0x1 
#define SHF_ALLOC		0x2
#define SHF_EXECINSTR		0x4
#define SHF_MASKPROC		0xf0000000

/**
 * Symbol binding
 */
#define STB_LOCAL		0
#define STB_GLOBAL		1
#define STB_WEAK		2
#define STB_LOPROC		13
#define STB_HIPROC		15

/**
 * Symbol types
 */
#define STT_NOTYPE		0
#define STT_OBJECT		1
#define STT_FUNC		2
#define STT_SECTION		3
#define STT_FILE		4
#define STT_LOPROC		13
#define STT_HIPROC		15

/**
 * Program segment types
 */
#define PT_NULL			0
#define PT_LOAD			1
#define PT_DYNAMIC		2
#define PT_INTERP		3
#define PT_NOTE			4
#define PT_SHLIB		5
#define PT_PHDR			6
#define PT_LOPROC		0x70000000
#define PT_HIPROC		0x7fffffff

/**
 * Program segment attributes.
 */
#define PF_X	1
#define PF_W	2
#define PF_R	4

/**
 * ELF data types
 *
 * These types are found to be identical in both 32-bit and 64-bit
 * ELF object file specifications. They are the only types used
 * in ELF header.
 */
typedef __u64 elf_xword;
typedef __s64 elf_sxword;
typedef __u32 elf_word;
typedef __s32 elf_sword;
typedef __u16 elf_half;

/**
 * 32-bit ELF data types.
 *
 * These types are specific for 32-bit format.
 */
typedef __u32 elf32_addr;
typedef __u32 elf32_off;

/**
 * 64-bit ELF data types.
 *
 * These types are specific for 64-bit format.
 */
typedef __u64 elf64_addr;
typedef __u64 elf64_off;

/** ELF header */
struct elf32_header {
	__u8 e_ident[EI_NIDENT];
	elf_half e_type;
	elf_half e_machine;
	elf_word e_version;
	elf32_addr e_entry;
	elf32_off e_phoff;
	elf32_off e_shoff;
	elf_word e_flags;
	elf_half e_ehsize;
	elf_half e_phentsize;
	elf_half e_phnum;
	elf_half e_shentsize;
	elf_half e_shnum;
	elf_half e_shstrndx;
};
struct elf64_header {
	__u8 e_ident[EI_NIDENT];
	elf_half e_type;
	elf_half e_machine;
	elf_word e_version;
	elf64_addr e_entry;
	elf64_off e_phoff;
	elf64_off e_shoff;
	elf_word e_flags;
	elf_half e_ehsize;
	elf_half e_phentsize;
	elf_half e_phnum;
	elf_half e_shentsize;
	elf_half e_shnum;
	elf_half e_shstrndx;
};

/*
 * ELF segment header.
 * Segments headers are also known as program headers.
 */
struct elf32_segment_header {
	elf_word p_type;
	elf32_off p_offset;
	elf32_addr p_vaddr;
	elf32_addr p_paddr;
	elf_word p_filesz;
	elf_word p_memsz;
	elf_word p_flags;
	elf_word p_align;
};
struct elf64_segment_header {
	elf_word p_type;
	elf_word p_flags;
	elf64_off p_offset;
	elf64_addr p_vaddr;
	elf64_addr p_paddr;
	elf_xword p_filesz;
	elf_xword p_memsz;
	elf_xword p_align;
};

/*
 * ELF section header
 */
struct elf32_section_header {
	elf_word sh_name;
	elf_word sh_type;
	elf_word sh_flags;
	elf32_addr sh_addr;
	elf32_off sh_offset;
	elf_word sh_size;
	elf_word sh_link;
	elf_word sh_info;
	elf_word sh_addralign;
	elf_word sh_entsize;
};
struct elf64_section_header {
	elf_word sh_name;
	elf_word sh_type;
	elf_xword sh_flags;
	elf64_addr sh_addr;
	elf64_off sh_offset;
	elf_xword sh_size;
	elf_word sh_link;
	elf_word sh_info;
	elf_xword sh_addralign;
	elf_xword sh_entsize;
};

/*
 * ELF symbol table entry
 */
struct elf32_symbol {
	elf_word st_name;
	elf32_addr st_value;
	elf_word st_size;
	__u8 st_info;
	__u8 st_other;
	elf_half st_shndx;
};
struct elf64_symbol {
	elf_word st_name;
	__u8 st_info;
	__u8 st_other;
	elf_half st_shndx;
	elf64_addr st_value;
	elf_xword st_size;
};

#ifdef __32_BITS__ 
typedef struct elf32_header elf_header_t;
typedef struct elf32_segment_header elf_segment_header_t;
typedef struct elf32_section_header elf_section_header_t;
typedef struct elf32_symbol elf_symbol_t;
#endif
#ifdef __64_BITS__
typedef struct elf64_header elf_header_t;
typedef struct elf64_segment_header elf_segment_header_t;
typedef struct elf64_section_header elf_section_header_t;
typedef struct elf64_symbol elf_symbol_t;
#endif

extern int elf_load(elf_header_t *header, as_t * as);
extern char *elf_error(int rc);

#endif