/*
   * sortextable.h
   *

   * Copyright 2011 - 2012 Cavium, Inc.

   *
   * Some of this code was taken out of recordmcount.h written by:
   *
   * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>.  All rights reserved.
   * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
   *
   *
   * Licensed under the GNU General Public License, version 2 (GPLv2).
   */
  
  #undef extable_ent_size
  #undef compare_extable
  #undef do_func
  #undef Elf_Addr
  #undef Elf_Ehdr
  #undef Elf_Shdr
  #undef Elf_Rel
  #undef Elf_Rela
  #undef Elf_Sym
  #undef ELF_R_SYM
  #undef Elf_r_sym
  #undef ELF_R_INFO
  #undef Elf_r_info
  #undef ELF_ST_BIND
  #undef ELF_ST_TYPE
  #undef fn_ELF_R_SYM
  #undef fn_ELF_R_INFO
  #undef uint_t

  #undef _r

  #undef _w
  
  #ifdef SORTEXTABLE_64
  # define extable_ent_size	16
  # define compare_extable	compare_extable_64
  # define do_func		do64
  # define Elf_Addr		Elf64_Addr
  # define Elf_Ehdr		Elf64_Ehdr
  # define Elf_Shdr		Elf64_Shdr
  # define Elf_Rel		Elf64_Rel
  # define Elf_Rela		Elf64_Rela
  # define Elf_Sym		Elf64_Sym
  # define ELF_R_SYM		ELF64_R_SYM
  # define Elf_r_sym		Elf64_r_sym
  # define ELF_R_INFO		ELF64_R_INFO
  # define Elf_r_info		Elf64_r_info
  # define ELF_ST_BIND		ELF64_ST_BIND
  # define ELF_ST_TYPE		ELF64_ST_TYPE
  # define fn_ELF_R_SYM		fn_ELF64_R_SYM
  # define fn_ELF_R_INFO		fn_ELF64_R_INFO
  # define uint_t			uint64_t

  # define _r			r8

  # define _w			w8
  #else
  # define extable_ent_size	8
  # define compare_extable	compare_extable_32
  # define do_func		do32
  # define Elf_Addr		Elf32_Addr
  # define Elf_Ehdr		Elf32_Ehdr
  # define Elf_Shdr		Elf32_Shdr
  # define Elf_Rel		Elf32_Rel
  # define Elf_Rela		Elf32_Rela
  # define Elf_Sym		Elf32_Sym
  # define ELF_R_SYM		ELF32_R_SYM
  # define Elf_r_sym		Elf32_r_sym
  # define ELF_R_INFO		ELF32_R_INFO
  # define Elf_r_info		Elf32_r_info
  # define ELF_ST_BIND		ELF32_ST_BIND
  # define ELF_ST_TYPE		ELF32_ST_TYPE
  # define fn_ELF_R_SYM		fn_ELF32_R_SYM
  # define fn_ELF_R_INFO		fn_ELF32_R_INFO
  # define uint_t			uint32_t

  # define _r			r

  # define _w			w
  #endif
  
  static int compare_extable(const void *a, const void *b)
  {

  	Elf_Addr av = _r(a);
  	Elf_Addr bv = _r(b);

  	if (av < bv)

  		return -1;

  	if (av > bv)

  		return 1;
  	return 0;
  }
  
  static void

  do_func(Elf_Ehdr *ehdr, char const *const fname, table_sort_t custom_sort)

  {
  	Elf_Shdr *shdr;
  	Elf_Shdr *shstrtab_sec;
  	Elf_Shdr *strtab_sec = NULL;
  	Elf_Shdr *symtab_sec = NULL;
  	Elf_Shdr *extab_sec = NULL;
  	Elf_Sym *sym;

  	const Elf_Sym *symtab;
  	Elf32_Word *symtab_shndx_start = NULL;

  	Elf_Sym *sort_needed_sym;
  	Elf_Shdr *sort_needed_sec;

  	Elf_Rel *relocs = NULL;
  	int relocs_size;

  	uint32_t *sort_done_location;
  	const char *secstrtab;
  	const char *strtab;

  	char *extab_image;
  	int extab_index = 0;

  	int i;
  	int idx;

  	unsigned int num_sections;
  	unsigned int secindex_strings;

  	shdr = (Elf_Shdr *)((char *)ehdr + _r(&ehdr->e_shoff));

  
  	num_sections = r2(&ehdr->e_shnum);
  	if (num_sections == SHN_UNDEF)
  		num_sections = _r(&shdr[0].sh_size);
  
  	secindex_strings = r2(&ehdr->e_shstrndx);
  	if (secindex_strings == SHN_XINDEX)
  		secindex_strings = r(&shdr[0].sh_link);
  
  	shstrtab_sec = shdr + secindex_strings;

  	secstrtab = (const char *)ehdr + _r(&shstrtab_sec->sh_offset);

  	for (i = 0; i < num_sections; i++) {

  		idx = r(&shdr[i].sh_name);
  		if (strcmp(secstrtab + idx, "__ex_table") == 0) {

  			extab_sec = shdr + i;

  			extab_index = i;
  		}
  		if ((r(&shdr[i].sh_type) == SHT_REL ||
  		     r(&shdr[i].sh_type) == SHT_RELA) &&
  		    r(&shdr[i].sh_info) == extab_index) {
  			relocs = (void *)ehdr + _r(&shdr[i].sh_offset);
  			relocs_size = _r(&shdr[i].sh_size);
  		}

  		if (strcmp(secstrtab + idx, ".symtab") == 0)
  			symtab_sec = shdr + i;
  		if (strcmp(secstrtab + idx, ".strtab") == 0)
  			strtab_sec = shdr + i;

  		if (r(&shdr[i].sh_type) == SHT_SYMTAB_SHNDX)
  			symtab_shndx_start = (Elf32_Word *)(
  				(const char *)ehdr + _r(&shdr[i].sh_offset));

  	}
  	if (strtab_sec == NULL) {
  		fprintf(stderr,	"no .strtab in  file: %s
  ", fname);
  		fail_file();
  	}
  	if (symtab_sec == NULL) {
  		fprintf(stderr,	"no .symtab in  file: %s
  ", fname);
  		fail_file();
  	}

  	symtab = (const Elf_Sym *)((const char *)ehdr +
  				   _r(&symtab_sec->sh_offset));

  	if (extab_sec == NULL) {
  		fprintf(stderr,	"no __ex_table in  file: %s
  ", fname);
  		fail_file();
  	}

  	strtab = (const char *)ehdr + _r(&strtab_sec->sh_offset);

  	extab_image = (void *)ehdr + _r(&extab_sec->sh_offset);
  
  	if (custom_sort) {
  		custom_sort(extab_image, _r(&extab_sec->sh_size));
  	} else {
  		int num_entries = _r(&extab_sec->sh_size) / extable_ent_size;
  		qsort(extab_image, num_entries,
  		      extable_ent_size, compare_extable);
  	}
  	/* If there were relocations, we no longer need them. */
  	if (relocs)
  		memset(relocs, 0, relocs_size);

  
  	/* find main_extable_sort_needed */
  	sort_needed_sym = NULL;

  	for (i = 0; i < _r(&symtab_sec->sh_size) / sizeof(Elf_Sym); i++) {
  		sym = (void *)ehdr + _r(&symtab_sec->sh_offset);

  		sym += i;
  		if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT)
  			continue;

  		idx = r(&sym->st_name);

  		if (strcmp(strtab + idx, "main_extable_sort_needed") == 0) {
  			sort_needed_sym = sym;
  			break;
  		}
  	}
  	if (sort_needed_sym == NULL) {
  		fprintf(stderr,
  			"no main_extable_sort_needed symbol in  file: %s
  ",
  			fname);
  		fail_file();
  	}

  	sort_needed_sec = &shdr[get_secindex(r2(&sym->st_shndx),
  					     sort_needed_sym - symtab,
  					     symtab_shndx_start)];

  	sort_done_location = (void *)ehdr +

  		_r(&sort_needed_sec->sh_offset) +
  		_r(&sort_needed_sym->st_value) -
  		_r(&sort_needed_sec->sh_addr);

  #if 0

  	printf("sort done marker at %lx
  ",

  	       (unsigned long)((char *)sort_done_location - (char *)ehdr));
  #endif

  	/* We sorted it, clear the flag. */

  	w(0, sort_done_location);

  }