/**
 *  Copyright (C) NAKAMURA Minoru <nminoru@nminoru.jp>
 *
 *  gcc disassembler.c -lopcodes -lbfd -liberty
 */

#include <stdio.h>
#include <stdlib.h>
#include <bfd.h>
#include <dis-asm.h>

static int read_memory_func(bfd_vma memaddr, bfd_byte *myaddr, unsigned int length, struct disassemble_info *info);

/**
 *  start_memaddr から length バイト分の命令を逆アセンブラした結果を
 *  stream に出力する。
 */
extern int 
disassemble_instructions(const char* start_memaddr, int length, FILE* stream)
{
  disassemble_info  dinfo;

  int ret = 0;

  bfd_vma start, end, eip;

  bfd_init();

  INIT_DISASSEMBLE_INFO(dinfo, stdout, (fprintf_ftype) fprintf);
  dinfo.read_memory_func = read_memory_func;

  start = (bfd_vma) start_memaddr;
  end   = (bfd_vma) start + length;

#if defined(__i386__)
  dinfo.mach = bfd_mach_i386_i386;
#elif defined(__x86_64__)
  dinfo.mach = bfd_mach_x86_64;
#endif

  for (eip = start; eip < end ;) {
    int ret;
    unsigned char* p = (unsigned char*) eip;

#if defined(__ia64__)			
    fprintf(stream, "%p %02x %02x %02x %02x %02x %02x : ",
	    p, p[0], p[1], p[2], p[3], p[4], p[5]);
    fflush(stream);
    ret = print_insn_ia64(eip, &dinfo);
    fflush(stream);
    fprintf(stream, " \n");
    fflush(stream);

#elif defined(__i386__) || defined(__x86_64__) 
    fprintf(stream, "%p : ", p);
    fflush(stream);
    ret = print_insn_i386(eip, &dinfo);
    fflush(stream);
    fprintf(stream, " \n");
    fflush(stream);
#else
#error "Not supported for this platform."
#endif

    if (ret <= 0) {
      break;
    } else {
      eip += ret;
    }
  }

  return 0;
}


static int read_memory_func(bfd_vma memaddr, bfd_byte *myaddr,
			    unsigned int length,
                            struct disassemble_info *info)
{
  int i;

  for (i=0 ; i<length; i++) {
    myaddr[i] = ((char*)memaddr)[i];
  }

  return 0;
}


int main(int argc, char** argv)
{
  disassemble_instructions(main, 64, stdout);
}