#include "nextstep-nat-inferior.h"
#include "nextstep-nat-mutils.h"

#include "defs.h"
#include "inferior.h"
#include "symfile.h"
#include "symtab.h"
#include "gdbcmd.h"
#include "objfiles.h"

#include <string.h>

#include <mach-o/nlist.h>
#include <mach-o/loader.h>
#include <mach-o/dyld_debug.h>

#include "mach-o.h"

struct inferior_info {
  bfd_vma addr;
  bfd_vma offset;
  bfd_vma len;
};

static bfd_size_type
inferior_read
(PTR iodata, PTR data, bfd_size_type size, bfd_size_type nitems, bfd *abfd, bfd_vma where)
{
  struct inferior_info *iptr = (struct inferior_info *) iodata;
  int ret;

  CHECK_FATAL (iptr != NULL);
  
  if (strcmp (current_target.to_shortname, "macos-child") != 0) {
    bfd_set_error (bfd_error_no_contents);
    return 0;
  }

  if (where > iptr->len) {
    bfd_set_error (bfd_error_no_contents);
    return 0;
  }

  ret = current_target.to_xfer_memory (iptr->addr + where, data, (size * nitems), 0, &current_target);
  if (ret <= 0) {
    bfd_set_error (bfd_error_system_call);
    return 0;
  }
  return ret;
}

static bfd_size_type
mach_o_inferior_read
(PTR iodata, PTR data, bfd_size_type size, bfd_size_type nitems, bfd *abfd, bfd_vma where)
{
  struct inferior_info *iptr = (struct inferior_info *) iodata;
  unsigned int i;
  int ret;

  CHECK_FATAL (iptr != NULL);
  
  if (strcmp (current_target.to_shortname, "macos-child") != 0) {
    bfd_set_error (bfd_error_no_contents);
    return 0;
  }

  if ((strcmp (bfd_get_target (abfd), "mach-o-be") != 0)
      && (strcmp (bfd_get_target (abfd), "mach-o-le") != 0)
      && (strcmp (bfd_get_target (abfd), "mach-o") != 0)) {
    bfd_set_error (bfd_error_invalid_target);
    return 0;
  }
  
  {
    struct mach_o_data_struct *mdata = NULL;
    CHECK_FATAL (bfd_mach_o_valid (abfd));
    mdata = abfd->tdata.mach_o_data;
    for (i = 0; i < mdata->header.ncmds; i++) {
      struct bfd_mach_o_load_command *cmd = &mdata->commands[i];
      if (cmd->type == BFD_MACH_O_LC_SEGMENT) {
	struct bfd_mach_o_segment_command *segment = &cmd->command.segment;
	if ((where >= segment->fileoff)
	    && (where < (segment->fileoff + segment->filesize))) {
	  bfd_vma infaddr = (segment->vmaddr + iptr->offset + (where - segment->fileoff));
	  ret = current_target.to_xfer_memory
	    (infaddr, data, (size * nitems), 0, &current_target);
	  if (ret <= 0) {
	    bfd_set_error (bfd_error_system_call);
	    return 0;
	  }
	  return ret;
	}
      }
    }
  }

  
  bfd_set_error (bfd_error_no_contents);
  return 0;
}

static bfd_size_type
inferior_write
(PTR iodata, const PTR data, bfd_size_type size, bfd_size_type nitems, bfd *abfd, bfd_vma where)
{
  error ("unable to write to in-memory images");
}

static int
inferior_flush (PTR iodata, bfd *abfd)
{
  return 0;
}

static boolean
inferior_close (PTR iodata, bfd *abfd)
{
  xfree (iodata);
  return 1;
}

static bfd_vma
extend_vma (unsigned long n)
{
  return (- ((bfd_vma) (- ((long) n))));
}

static bfd *
inferior_bfd_generic
(const char *name, CORE_ADDR addr, CORE_ADDR offset, CORE_ADDR len)
{
  struct inferior_info *iptr = NULL;
  struct bfd_io_functions fdata;
  char *filename = NULL;
  bfd *ret = NULL;
  int iret = 0;

  iptr = (struct inferior_info *) xmalloc (sizeof (struct inferior_info));
  iptr->addr = addr;
  iptr->offset = extend_vma (offset);
  iptr->len = len;

  fdata.iodata = iptr;
  fdata.read_func = &inferior_read;
  fdata.write_func = &inferior_write;
  fdata.flush_func = &inferior_flush;
  fdata.close_func = &inferior_close;

  iret = asprintf (&filename, "[memory object \"%s\" at 0x%lx for 0x%lx]",
		   name, (unsigned long) addr, (unsigned long) len);
  if (iret == 0) {
    warning ("unable to allocate memory for filename for \"%s\"", name);
    return NULL;
  }

  ret = bfd_funopenr (filename, NULL, &fdata);
  if (ret == NULL) { 
    warning ("Unable to open memory image for \"%s\"; skipping", name);
    return NULL;
  }
  
  if (bfd_check_format (ret, bfd_archive))
    {
      bfd *abfd = NULL;
#if defined (__ppc__)
      const bfd_arch_info_type *thisarch = bfd_lookup_arch (bfd_arch_powerpc, 0);
#elif defined (__i386__)
      const bfd_arch_info_type *thisarch = bfd_lookup_arch (bfd_arch_i386, 0);
#else
      const bfd_arch_info_type *thisarch = bfd_lookup_arch (bfd_arch_powerpc, 0);
#endif
      for (;;) {
	abfd = bfd_openr_next_archived_file (ret, abfd);
	if (abfd == NULL) { break; }
	if (! bfd_check_format (abfd, bfd_object)) { abfd = NULL; break; }
	if (thisarch == NULL) { abfd = NULL; break; }

	if (bfd_default_compatible (bfd_get_arch_info (abfd), thisarch)) { break; } 
      }
      if (abfd != NULL) { 
	ret = abfd;
      }
    }

  /* FIXME: should check for errors from bfd_close (for one thing, on
     error it does not free all the storage associated with the bfd).  */

  if (! bfd_check_format (ret, bfd_object)) {
    warning ("Unable to read symbols from %s: %s.", bfd_get_filename (ret), bfd_errmsg (bfd_get_error ()));
    bfd_close (ret);
    return NULL;
  }

  return ret;
}

bfd *
inferior_bfd
(const char *name, CORE_ADDR addr, CORE_ADDR offset, CORE_ADDR len)
{
  bfd *ret = inferior_bfd_generic (name, addr, offset, len);
  if (ret == NULL)
    return ret;

  if ((strcmp (bfd_get_target (ret), "mach-o-be") == 0)
      || (strcmp (bfd_get_target (ret), "mach-o-le") == 0)
      || (strcmp (bfd_get_target (ret), "mach-o") == 0)) 
    {
      struct bfd_io_functions *fun = (struct bfd_io_functions *) ret->iostream;
      CHECK_FATAL (fun != NULL);

      fun->read_func = mach_o_inferior_read;
    }

  if ((strcmp (bfd_get_target (ret), "pef") == 0)
      || (strcmp (bfd_get_target (ret), "pef-xlib") == 0))
    {
      struct bfd_io_functions *fun = (struct bfd_io_functions *) ret->iostream;
      CHECK_FATAL (fun != NULL);

      /* no changes necessary */
    }
  
  return ret;
}