/* SPDX-License-Identifier: GPL-2.0 */

  #include <stdio.h>
  #include <stdlib.h>
  #include <stdarg.h>
  #include <string.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <sys/mman.h>
  #include <fcntl.h>
  #include <unistd.h>
  #include <elf.h>
  
  #include "elfconfig.h"

  /* On BSD-alike OSes elf.h defines these according to host's word size */
  #undef ELF_ST_BIND
  #undef ELF_ST_TYPE
  #undef ELF_R_SYM
  #undef ELF_R_TYPE

  #if KERNEL_ELFCLASS == ELFCLASS32

  #define Elf_Ehdr    Elf32_Ehdr
  #define Elf_Shdr    Elf32_Shdr

  #define Elf_Sym     Elf32_Sym

  #define Elf_Addr    Elf32_Addr

  #define Elf_Sword   Elf64_Sword

  #define Elf_Section Elf32_Half

  #define ELF_ST_BIND ELF32_ST_BIND
  #define ELF_ST_TYPE ELF32_ST_TYPE

  #define Elf_Rel     Elf32_Rel

  #define Elf_Rela    Elf32_Rela
  #define ELF_R_SYM   ELF32_R_SYM
  #define ELF_R_TYPE  ELF32_R_TYPE

  #else

  #define Elf_Ehdr    Elf64_Ehdr
  #define Elf_Shdr    Elf64_Shdr

  #define Elf_Sym     Elf64_Sym

  #define Elf_Addr    Elf64_Addr

  #define Elf_Sword   Elf64_Sxword

  #define Elf_Section Elf64_Half

  #define ELF_ST_BIND ELF64_ST_BIND
  #define ELF_ST_TYPE ELF64_ST_TYPE

  #define Elf_Rel     Elf64_Rel

  #define Elf_Rela    Elf64_Rela
  #define ELF_R_SYM   ELF64_R_SYM
  #define ELF_R_TYPE  ELF64_R_TYPE

  #endif

  /* The 64-bit MIPS ELF ABI uses an unusual reloc format. */
  typedef struct
  {
  	Elf32_Word    r_sym;	/* Symbol index */
  	unsigned char r_ssym;	/* Special symbol for 2nd relocation */
  	unsigned char r_type3;	/* 3rd relocation type */
  	unsigned char r_type2;	/* 2nd relocation type */
  	unsigned char r_type1;	/* 1st relocation type */
  } _Elf64_Mips_R_Info;
  
  typedef union
  {
  	Elf64_Xword		r_info_number;
  	_Elf64_Mips_R_Info	r_info_fields;
  } _Elf64_Mips_R_Info_union;
  
  #define ELF64_MIPS_R_SYM(i) \
    ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym)

  #define ELF64_MIPS_R_TYPE(i) \
    ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1)

  #if KERNEL_ELFDATA != HOST_ELFDATA
  
  static inline void __endian(const void *src, void *dest, unsigned int size)
  {
  	unsigned int i;
  	for (i = 0; i < size; i++)
  		((unsigned char*)dest)[i] = ((unsigned char*)src)[size - i-1];
  }

  #define TO_NATIVE(x)						\
  ({								\
  	typeof(x) __x;						\
  	__endian(&(x), &(__x), sizeof(__x));			\
  	__x;							\
  })
  
  #else /* endianness matches */
  
  #define TO_NATIVE(x) (x)
  
  #endif
  
  #define NOFAIL(ptr)   do_nofail((ptr), #ptr)
  void *do_nofail(void *ptr, const char *expr);
  
  struct buffer {
  	char *p;
  	int pos;
  	int size;
  };
  
  void __attribute__((format(printf, 2, 3)))
  buf_printf(struct buffer *buf, const char *fmt, ...);
  
  void
  buf_write(struct buffer *buf, const char *s, int len);
  
  struct module {
  	struct module *next;
  	const char *name;

  	int gpl_compatible;

  	struct symbol *unres;
  	int seen;
  	int skip;
  	int has_init;
  	int has_cleanup;
  	struct buffer dev_table_buf;
  	char	     srcversion[25];

  	int is_dot_o;

  };
  
  struct elf_info {
  	unsigned long size;
  	Elf_Ehdr     *hdr;
  	Elf_Shdr     *sechdrs;
  	Elf_Sym      *symtab_start;
  	Elf_Sym      *symtab_stop;

  	Elf_Section  export_sec;

  	Elf_Section  export_unused_sec;

  	Elf_Section  export_gpl_sec;

  	Elf_Section  export_unused_gpl_sec;

  	Elf_Section  export_gpl_future_sec;

  	char         *strtab;

  	char	     *modinfo;
  	unsigned int modinfo_len;

  
  	/* support for 32bit section numbers */
  
  	unsigned int num_sections; /* max_secindex + 1 */
  	unsigned int secindex_strings;
  	/* if Nth symbol table entry has .st_shndx = SHN_XINDEX,
  	 * take shndx from symtab_shndx_start[N] instead */
  	Elf32_Word   *symtab_shndx_start;
  	Elf32_Word   *symtab_shndx_stop;

  };

  static inline int is_shndx_special(unsigned int i)
  {
  	return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
  }

  /*
   * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
   * the way to -256..-1, to avoid conflicting with real section
   * indices.

   */

  #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))

  
  /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
  static inline unsigned int get_secindex(const struct elf_info *info,
  					const Elf_Sym *sym)
  {

  	if (is_shndx_special(sym->st_shndx))
  		return SPECIAL(sym->st_shndx);

  	if (sym->st_shndx != SHN_XINDEX)
  		return sym->st_shndx;

  	return info->symtab_shndx_start[sym - info->symtab_start];

  }

  /* file2alias.c */

  extern unsigned int cross_build;

  void handle_moddevtable(struct module *mod, struct elf_info *info,
  			Elf_Sym *sym, const char *symname);

  void add_moddevtable(struct buffer *buf, struct module *mod);

  /* sumversion.c */

  void maybe_frob_rcs_version(const char *modfilename,
  			    char *version,
  			    void *modinfo,
  			    unsigned long modinfo_offset);
  void get_src_version(const char *modname, char sum[], unsigned sumlen);

  /* from modpost.c */

  void *grab_file(const char *filename, unsigned long *size);
  char* get_next_line(unsigned long *pos, void *file, unsigned long size);
  void release_file(void *file, unsigned long size);

  
  void fatal(const char *fmt, ...);
  void warn(const char *fmt, ...);

  void merror(const char *fmt, ...);