path: root/binutils/nlmconv.c

/* nlmconv.c -- NLM conversion program
   Copyright (C) 1993 Free Software Foundation, Inc.

This file is part of GNU Binutils.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

/* Written by Ian Lance Taylor <ian@cygnus.com>.

   This program can be used to convert any appropriate object file
   into a NetWare Loadable Module (an NLM).  It will accept a linker
   specification file which is identical to that accepted by the
   NetWare linker, NLMLINK, except that the INPUT command, normally
   used to give a list of object files to link together, is not used.
   This program will convert only a single object file.  */

#include <ansidecl.h>
#include <stdio.h>
#include <time.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <assert.h>
#include <getopt.h>
#include <bfd.h>
#include "sysdep.h"
#include "bucomm.h"
/* Internal BFD NLM header.  */
#include "libnlm.h"
#include "nlmconv.h"

/* Needed for Alpha support.  */
#include "coff/sym.h"
#include "coff/ecoff.h"

/* If strerror is just a macro, we want to use the one from libiberty
   since it will handle undefined values.  */
#undef strerror
extern char *strerror ();

#ifndef localtime
extern struct tm *localtime ();
#endif

#ifndef getenv
extern char *getenv ();
#endif

#ifndef SEEK_SET
#define SEEK_SET 0
#endif

#ifndef R_OK
#define R_OK 4
#define W_OK 2
#define X_OK 1
#endif

/* Global variables.  */

/* The name used to invoke the program.  */
char *program_name;

/* The version number.  */
extern char *program_version;

/* Local variables.  */

/* Whether to print out debugging information (currently just controls
   whether it prints the linker command if there is one).  */
static int debug;

/* The symbol table.  */
static asymbol **symbols;

/* A temporary file name to be unlinked on exit.  Actually, for most
   errors, we leave it around.  It's not clear whether that is helpful
   or not.  */
static char *unlink_on_exit;

/* The list of long options.  */
static struct option long_options[] =
{
  { "debug", no_argument, 0, 'd' },
  { "header-file", required_argument, 0, 'T' },
  { "help", no_argument, 0, 'h' },
  { "input-format", required_argument, 0, 'I' },
  { "linker", required_argument, 0, 'l' },
  { "output-format", required_argument, 0, 'O' },
  { "version", no_argument, 0, 'V' },
  { NULL, no_argument, 0, 0 }
};

/* Local routines.  */

static void show_help PARAMS ((void));
static void show_usage PARAMS ((FILE *, int));
static const char *select_output_format PARAMS ((enum bfd_architecture,
						 unsigned long, boolean));
static void setup_sections PARAMS ((bfd *, asection *, PTR));
static void copy_sections PARAMS ((bfd *, asection *, PTR));
static void mangle_relocs PARAMS ((bfd *, asection *, arelent ***,
				   bfd_size_type *, char *,
				   bfd_size_type));
static void i386_mangle_relocs PARAMS ((bfd *, asection *, arelent ***,
					bfd_size_type *, char *,
					bfd_size_type));
static void alpha_mangle_relocs PARAMS ((bfd *, asection *, arelent ***,
					 bfd_size_type *, char *,
					 bfd_size_type));
static void default_mangle_relocs PARAMS ((bfd *, asection *, arelent ***,
					   bfd_size_type *, char *,
					   bfd_size_type));
static char *link_inputs PARAMS ((struct string_list *, char *));
static const char *choose_temp_base_try PARAMS ((const char *,
						 const char *));
static void choose_temp_base PARAMS ((void));
static int pexecute PARAMS ((char *, char *[]));

/* The main routine.  */

int
main (argc, argv)
     int argc;
     char **argv;
{
  int opt;
  char *input_file = NULL;
  const char *input_format = NULL;
  const char *output_format = NULL;
  const char *header_file = NULL;
  char *ld_arg = NULL;
  Nlm_Internal_Fixed_Header fixed_hdr_struct;
  Nlm_Internal_Variable_Header var_hdr_struct;
  Nlm_Internal_Version_Header version_hdr_struct;
  Nlm_Internal_Copyright_Header copyright_hdr_struct;
  Nlm_Internal_Extended_Header extended_hdr_struct;
  bfd *inbfd;
  bfd *outbfd;
  asymbol **newsyms, **outsyms;
  unsigned int symcount, newsymalloc, newsymcount;
  asection *bss_sec, *data_sec;
  bfd_vma vma;
  bfd_size_type align;
  asymbol *endsym;
  unsigned int i;
  char inlead, outlead;
  boolean gotstart, gotexit, gotcheck;
  struct stat st;
  FILE *custom_data, *help_data, *message_data, *rpc_data, *shared_data;
  size_t custom_size, help_size, message_size, module_size, rpc_size;
  asection *custom_section, *help_section, *message_section, *module_section;
  asection *rpc_section, *shared_section;
  bfd *sharedbfd;
  size_t shared_offset, shared_size;
  Nlm_Internal_Fixed_Header sharedhdr;
  int len;
  char *modname;

  program_name = argv[0];

  bfd_init ();

  while ((opt = getopt_long (argc, argv, "dhI:l:O:T:V", long_options,
			     (int *) NULL))
	 != EOF)
    {
      switch (opt)
	{
	case 'd':
	  debug = 1;
	  break;
	case 'h':
	  show_help ();
	  /*NOTREACHED*/
	case 'I':
	  input_format = optarg;
	  break;
	case 'l':
	  ld_arg = optarg;
	  break;
	case 'O':
	  output_format = optarg;
	  break;
	case 'T':
	  header_file = optarg;
	  break;
	case 'V':
	  printf ("GNU %s version %s\n", program_name, program_version);
	  exit (0);
	  /*NOTREACHED*/
	case 0:
	  break;
	default:
	  show_usage (stderr, 1);
	  /*NOTREACHED*/
	}
    }

  /* The input and output files may be named on the command line.  */
  output_file = NULL;
  if (optind < argc)
    {
      input_file = argv[optind];
      ++optind;
      if (optind < argc)
	{
	  output_file = argv[optind];
	  ++optind;
	  if (optind < argc)
	    show_usage (stderr, 1);
	  if (strcmp (input_file, output_file) == 0)
	    {
	      fprintf (stderr,
		       "%s: input and output files must be different\n",
		       program_name);
	      exit (1);
	    }
	}
    }

  /* Initialize the header information to default values.  */
  fixed_hdr = &fixed_hdr_struct;
  memset ((PTR) &fixed_hdr_struct, 0, sizeof fixed_hdr_struct);
  var_hdr = &var_hdr_struct;
  memset ((PTR) &var_hdr_struct, 0, sizeof var_hdr_struct);
  version_hdr = &version_hdr_struct;
  memset ((PTR) &version_hdr_struct, 0, sizeof version_hdr_struct);
  copyright_hdr = &copyright_hdr_struct;
  memset ((PTR) &copyright_hdr_struct, 0, sizeof copyright_hdr_struct);
  extended_hdr = &extended_hdr_struct;
  memset ((PTR) &extended_hdr_struct, 0, sizeof extended_hdr_struct);
  check_procedure = NULL;
  custom_file = NULL;
  debug_info = false;
  exit_procedure = "_Stop";
  export_symbols = NULL;
  map_file = NULL;
  full_map = false;
  help_file = NULL;
  import_symbols = NULL;
  message_file = NULL;
  modules = NULL;
  sharelib_file = NULL;
  start_procedure = "_Prelude";
  verbose = false;
  rpc_file = NULL;

  parse_errors = 0;

  /* Parse the header file (if there is one).  */
  if (header_file != NULL)
    {
      if (! nlmlex_file (header_file)
	  || yyparse () != 0
	  || parse_errors != 0)
	exit (1);
    }

  if (input_files != NULL)
    {
      if (input_file != NULL)
	{
	  fprintf (stderr,
		   "%s: input file named both on command line and with INPUT\n",
		   program_name);
	  exit (1);
	}
      if (input_files->next == NULL)
	input_file = input_files->string;
      else
	input_file = link_inputs (input_files, ld_arg);
    }
  else if (input_file == NULL)
    {
      fprintf (stderr, "%s: no input file\n", program_name);
      show_usage (stderr, 1);
    }

  inbfd = bfd_openr (input_file, input_format);
  if (inbfd == NULL)
    bfd_fatal (input_file);

  if (! bfd_check_format (inbfd, bfd_object))
    bfd_fatal (input_file);

  if (output_format == NULL)
    output_format = select_output_format (bfd_get_arch (inbfd),
					  bfd_get_mach (inbfd),
					  inbfd->xvec->byteorder_big_p);

  assert (output_format != NULL);

  /* Use the output file named on the command line if it exists.
     Otherwise use the file named in the OUTPUT statement.  */
  if (output_file == NULL)
    {
      fprintf (stderr, "%s: no name for output file\n",
	       program_name);
      show_usage (stderr, 1);
    }

  outbfd = bfd_openw (output_file, output_format);
  if (outbfd == NULL)
    bfd_fatal (output_file);
  if (! bfd_set_format (outbfd, bfd_object))
    bfd_fatal (output_file);

  assert (outbfd->xvec->flavour == bfd_target_nlm_flavour);

  if (bfd_arch_get_compatible (inbfd, outbfd) == NULL)
    fprintf (stderr,
	     "%s: warning:input and output formats are not compatible\n",
	     program_name);

  /* Move the values read from the command file into outbfd.  */
  *nlm_fixed_header (outbfd) = fixed_hdr_struct;
  *nlm_variable_header (outbfd) = var_hdr_struct;
  *nlm_version_header (outbfd) = version_hdr_struct;
  *nlm_copyright_header (outbfd) = copyright_hdr_struct;
  *nlm_extended_header (outbfd) = extended_hdr_struct;

  /* Start copying the input BFD to the output BFD.  */
  if (! bfd_set_file_flags (outbfd, bfd_get_file_flags (inbfd)))
    bfd_fatal (bfd_get_filename (outbfd));

  symbols = (asymbol **) xmalloc (get_symtab_upper_bound (inbfd));
  symcount = bfd_canonicalize_symtab (inbfd, symbols);

  /* Make sure we have a .bss section.  */
  bss_sec = bfd_get_section_by_name (outbfd, NLM_UNINITIALIZED_DATA_NAME);
  if (bss_sec == NULL)
    {
      bss_sec = bfd_make_section (outbfd, NLM_UNINITIALIZED_DATA_NAME);
      if (bss_sec == NULL
	  || ! bfd_set_section_flags (outbfd, bss_sec, SEC_ALLOC)
	  || ! bfd_set_section_alignment (outbfd, bss_sec, 1))
	bfd_fatal ("make .bss section");
    }

  /* Set up the sections.  */
  bfd_map_over_sections (inbfd, setup_sections, (PTR) outbfd);

  /* The .bss section immediately follows the .data section.  */
  data_sec = bfd_get_section_by_name (outbfd, NLM_INITIALIZED_DATA_NAME);
  if (data_sec != NULL)
    {
      bfd_size_type add;

      vma = bfd_get_section_size_before_reloc (data_sec);
      align = 1 << bss_sec->alignment_power;
      add = ((vma + align - 1) &~ (align - 1)) - vma;
      vma += add;
      if (! bfd_set_section_vma (outbfd, bss_sec, vma))
	bfd_fatal ("set .bss vma");
      if (add != 0)
	{
	  bfd_size_type data_size;

	  data_size = bfd_get_section_size_before_reloc (data_sec);
	  if (! bfd_set_section_size (outbfd, data_sec, data_size + add))
	    bfd_fatal ("set .data size");
	}
    }

  /* Adjust symbol information.  */
  inlead = bfd_get_symbol_leading_char (inbfd);
  outlead = bfd_get_symbol_leading_char (outbfd);
  gotstart = false;
  gotexit = false;
  gotcheck = false;
  newsymalloc = 10;
  newsyms = (asymbol **) xmalloc (newsymalloc * sizeof (asymbol *));
  newsymcount = 0;
  endsym = NULL;
  for (i = 0; i < symcount; i++)
    {
      register asymbol *sym;

      sym = symbols[i];

      /* Add or remove a leading underscore.  */
      if (inlead != outlead)
	{
	  if (inlead != '\0')
	    {
	      if (bfd_asymbol_name (sym)[0] == inlead)
		{
		  if (outlead == '\0')
		    ++sym->name;
		  else
		    {
		      char *new;

		      new = xmalloc (strlen (bfd_asymbol_name (sym)) + 1);
		      new[0] = outlead;
		      strcpy (new + 1, bfd_asymbol_name (sym) + 1);
		      sym->name = new;
		    }
		}
	    }
	  else
	    {
	      char *new;

	      new = xmalloc (strlen (bfd_asymbol_name (sym)) + 2);
	      new[0] = outlead;
	      strcpy (new + 1, bfd_asymbol_name (sym));
	      sym->name = new;
	    }
	}

      /* NLM's have an uninitialized data section, but they do not
	 have a common section in the Unix sense.  Move all common
	 symbols into the .bss section, and mark them as exported.  */
      if (bfd_is_com_section (bfd_get_section (sym)))
	{
	  bfd_vma size;

	  sym->section = bss_sec;
	  size = sym->value;
	  sym->value = bss_sec->_raw_size;
	  bss_sec->_raw_size += size;
	  align = 1 << bss_sec->alignment_power;
	  bss_sec->_raw_size = (bss_sec->_raw_size + align - 1) &~ (align - 1);
	  sym->flags |= BSF_EXPORT | BSF_GLOBAL;
	}
      else if (bfd_get_section (sym)->output_section != NULL)
	{
	  /* Move the symbol into the output section.  */
	  sym->value += bfd_get_section (sym)->output_offset;
	  sym->section = bfd_get_section (sym)->output_section;
	  /* This is no longer a section symbol.  */
	  sym->flags &=~ BSF_SECTION_SYM;
	}

      /* Force _edata and _end to be defined.  This would normally be
	 done by the linker, but the manipulation of the common
	 symbols will confuse it.  */
      if (bfd_asymbol_name (sym)[0] == '_'
	  && bfd_get_section (sym) == &bfd_und_section)
	{
	  if (strcmp (bfd_asymbol_name (sym), "_edata") == 0)
	    {
	      sym->section = bss_sec;
	      sym->value = 0;
	    }
	  if (strcmp (bfd_asymbol_name (sym), "_end") == 0)
	    {
	      sym->section = bss_sec;
	      endsym = sym;
	    }
	}

      /* If this is a global symbol, check the export list.  */
      if ((sym->flags & (BSF_EXPORT | BSF_GLOBAL)) != 0)
	{
	  register struct string_list *l;
	  int found_simple;

	  /* Unfortunately, a symbol can appear multiple times on the
	     export list, with and without prefixes.  */
	  found_simple = 0;
	  for (l = export_symbols; l != NULL; l = l->next)
	    {
	      if (strcmp (l->string, bfd_asymbol_name (sym)) == 0)
		found_simple = 1;
	      else
		{
		  char *zbase;

		  zbase = strchr (l->string, '@');
		  if (zbase != NULL
		      && strcmp (zbase + 1, bfd_asymbol_name (sym)) == 0)
		    {
		      /* We must add a symbol with this prefix.  */
		      if (newsymcount >= newsymalloc)
			{
			  newsymalloc += 10;
			  newsyms = ((asymbol **)
				     xrealloc (newsyms,
					       (newsymalloc
						* sizeof (asymbol *))));
			}
		      newsyms[newsymcount] =
			(asymbol *) xmalloc (sizeof (asymbol));
		      *newsyms[newsymcount] = *sym;
		      newsyms[newsymcount]->name = l->string;
		      ++newsymcount;
		    }
		}
	    }
	  if (! found_simple)
	    {
	      /* The unmodified symbol is actually not exported at
		 all.  */
	      sym->flags &=~ (BSF_GLOBAL | BSF_EXPORT);
	      sym->flags |= BSF_LOCAL;
	    }
	}

      /* If it's an undefined symbol, see if it's on the import list.
	 Change the prefix if necessary.  */
      if (bfd_get_section (sym) == &bfd_und_section)
	{
	  register struct string_list *l;

	  for (l = import_symbols; l != NULL; l = l->next)
	    {
	      if (strcmp (l->string, bfd_asymbol_name (sym)) == 0)
		break;
	      else
		{
		  char *zbase;

		  zbase = strchr (l->string, '@');
		  if (zbase != NULL
		      && strcmp (zbase + 1, bfd_asymbol_name (sym)) == 0)
		    {
		      sym->name = l->string;
		      break;
		    }
		}
	    }
	  if (l == NULL)
	    fprintf (stderr,
		     "%s: warning: symbol %s imported but not in import list\n",
		     program_name, bfd_asymbol_name (sym));
	}
	
      /* See if it's one of the special named symbols.  */
      if (strcmp (bfd_asymbol_name (sym), start_procedure) == 0)
	{
	  if (! bfd_set_start_address (outbfd, bfd_asymbol_value (sym)))
	    bfd_fatal ("set start address");
	  gotstart = true;
	}
      if (strcmp (bfd_asymbol_name (sym), exit_procedure) == 0)
	{
	  nlm_fixed_header (outbfd)->exitProcedureOffset =
	    bfd_asymbol_value (sym);
	  gotexit = true;
	}
      if (check_procedure != NULL
	  && strcmp (bfd_asymbol_name (sym), check_procedure) == 0)
	{
	  nlm_fixed_header (outbfd)->checkUnloadProcedureOffset =
	    bfd_asymbol_value (sym);
	  gotcheck = true;
	}
    }

  if (endsym != NULL)
    endsym->value = bfd_get_section_size_before_reloc (bss_sec);

  if (newsymcount == 0)
    outsyms = symbols;
  else
    {
      outsyms = (asymbol **) xmalloc ((symcount + newsymcount + 1)
				      * sizeof (asymbol *));
      memcpy (outsyms, symbols, symcount * sizeof (asymbol *));
      memcpy (outsyms + symcount, newsyms, newsymcount * sizeof (asymbol *));
      outsyms[symcount + newsymcount] = NULL;
    }

  bfd_set_symtab (outbfd, outsyms, symcount + newsymcount);
    
  if (! gotstart)
    fprintf (stderr, "%s: warning: START procedure %s not defined\n",
	     program_name, start_procedure);
  if (! gotexit)
    fprintf (stderr, "%s: warning: EXIT procedure %s not defined\n",
	     program_name, exit_procedure);
  if (check_procedure != NULL
      && ! gotcheck)
    fprintf (stderr, "%s: warning: CHECK procedure %s not defined\n",
	     program_name, check_procedure);

  /* Add additional sections required for the header information.  */
  if (custom_file != NULL)
    {
      custom_data = fopen (custom_file, "r");
      if (custom_data == NULL
	  || fstat (fileno (custom_data), &st) < 0)
	{
	  fprintf (stderr, "%s:%s: %s\n", program_name, custom_file,
		   strerror (errno));
	  custom_file = NULL;
	}
      else
	{
	  custom_size = st.st_size;
	  custom_section = bfd_make_section (outbfd, ".nlmcustom");
	  if (custom_section == NULL
	      || ! bfd_set_section_size (outbfd, custom_section, custom_size)
	      || ! bfd_set_section_flags (outbfd, custom_section,
					  SEC_HAS_CONTENTS))
	    bfd_fatal ("custom section");
	}
    }
  if (help_file != NULL)
    {
      help_data = fopen (help_file, "r");
      if (help_data == NULL
	  || fstat (fileno (help_data), &st) < 0)
	{
	  fprintf (stderr, "%s:%s: %s\n", program_name, help_file,
		   strerror (errno));
	  help_file = NULL;
	}
      else
	{
	  help_size = st.st_size;
	  help_section = bfd_make_section (outbfd, ".nlmhelp");
	  if (help_section == NULL
	      || ! bfd_set_section_size (outbfd, help_section, help_size)
	      || ! bfd_set_section_flags (outbfd, help_section,
					  SEC_HAS_CONTENTS))
	    bfd_fatal ("help section");
	  strncpy (nlm_extended_header (outbfd)->stamp, "MeSsAgEs", 8);
	}
    }
  if (message_file != NULL)
    {
      message_data = fopen (message_file, "r");
      if (message_data == NULL
	  || fstat (fileno (message_data), &st) < 0)
	{
	  fprintf (stderr, "%s:%s: %s\n", program_name, message_file,
		   strerror (errno));
	  message_file = NULL;
	}
      else
	{
	  message_size = st.st_size;
	  message_section = bfd_make_section (outbfd, ".nlmmessages");
	  if (message_section == NULL
	      || ! bfd_set_section_size (outbfd, message_section, message_size)
	      || ! bfd_set_section_flags (outbfd, message_section,
					  SEC_HAS_CONTENTS))
	    bfd_fatal ("message section");
	  strncpy (nlm_extended_header (outbfd)->stamp, "MeSsAgEs", 8);
	}
    }
  if (modules != NULL)
    {
      struct string_list *l;

      module_size = 0;
      for (l = modules; l != NULL; l = l->next)
	module_size += strlen (l->string) + 1;
      module_section = bfd_make_section (outbfd, ".nlmmodules");
      if (module_section == NULL
	  || ! bfd_set_section_size (outbfd, module_section, module_size)
	  || ! bfd_set_section_flags (outbfd, module_section,
				      SEC_HAS_CONTENTS))
	bfd_fatal ("module section");
    }
  if (rpc_file != NULL)
    {
      rpc_data = fopen (rpc_file, "r");
      if (rpc_data == NULL
	  || fstat (fileno (rpc_data), &st) < 0)
	{
	  fprintf (stderr, "%s:%s: %s\n", program_name, rpc_file,
		   strerror (errno));
	  rpc_file = NULL;
	}
      else
	{
	  rpc_size = st.st_size;
	  rpc_section = bfd_make_section (outbfd, ".nlmrpc");
	  if (rpc_section == NULL
	      || ! bfd_set_section_size (outbfd, rpc_section, rpc_size)
	      || ! bfd_set_section_flags (outbfd, rpc_section,
					  SEC_HAS_CONTENTS))
	    bfd_fatal ("rpc section");
	  strncpy (nlm_extended_header (outbfd)->stamp, "MeSsAgEs", 8);
	}
    }
  if (sharelib_file != NULL)
    {
      sharedbfd = bfd_openr (sharelib_file, output_format);
      if (sharedbfd == NULL
	  || ! bfd_check_format (sharedbfd, bfd_object))
	{
	  fprintf (stderr, "%s:%s: %s\n", program_name, sharelib_file,
		   bfd_errmsg (bfd_error));
	  sharelib_file = NULL;
	}
      else
	{
	  sharedhdr = *nlm_fixed_header (sharedbfd);
	  bfd_close (sharedbfd);
	  shared_data = fopen (sharelib_file, "r");
	  if (shared_data == NULL
	      || (fstat (fileno (shared_data), &st) < 0))
	    {
	      fprintf (stderr, "%s:%s: %s\n", program_name, sharelib_file,
		       strerror (errno));
	      sharelib_file = NULL;
	    }
	  else
	    {
	      /* If we were clever, we could just copy out the
		 sections of the shared library which we actually
		 need.  However, we would have to figure out the sizes
		 of the external and public information, and that can
		 not be done without reading through them.  */
	      shared_offset = st.st_size;
	      if (shared_offset > sharedhdr.codeImageOffset)
		shared_offset = sharedhdr.codeImageOffset;
	      if (shared_offset > sharedhdr.dataImageOffset)
		shared_offset = sharedhdr.dataImageOffset;
	      if (shared_offset > sharedhdr.relocationFixupOffset)
		shared_offset = sharedhdr.relocationFixupOffset;
	      if (shared_offset > sharedhdr.externalReferencesOffset)
		shared_offset = sharedhdr.externalReferencesOffset;
	      if (shared_offset > sharedhdr.publicsOffset)
		shared_offset = sharedhdr.publicsOffset;
	      shared_size = st.st_size - shared_offset;
	      shared_section = bfd_make_section (outbfd, ".nlmshared");
	      if (shared_section == NULL
		  || ! bfd_set_section_size (outbfd, shared_section,
					     shared_size)
		  || ! bfd_set_section_flags (outbfd, shared_section,
					      SEC_HAS_CONTENTS))
		bfd_fatal ("shared section");
	      strncpy (nlm_extended_header (outbfd)->stamp, "MeSsAgEs", 8);
	    }
	}
    }

  /* Check whether a version was given.  */
  if (strncmp (version_hdr->stamp, "VeRsIoN#", 8) != 0)
    fprintf (stderr, "%s: warning: No version number given\n",
	     program_name);

  /* At least for now, always create an extended header, because that
     is what NLMLINK does.  */
  strncpy (nlm_extended_header (outbfd)->stamp, "MeSsAgEs", 8);

  /* If the date was not given, force it in.  */
  if (nlm_version_header (outbfd)->month == 0
      && nlm_version_header (outbfd)->day == 0
      && nlm_version_header (outbfd)->year == 0)
    {
      time_t now;
      struct tm *ptm;

      time (&now);
      ptm = localtime (&now);
      nlm_version_header (outbfd)->month = ptm->tm_mon + 1;
      nlm_version_header (outbfd)->day = ptm->tm_mday;
      nlm_version_header (outbfd)->year = ptm->tm_year + 1900;
      strncpy (version_hdr->stamp, "VeRsIoN#", 8);
    }

  /* Copy over the sections.  */
  bfd_map_over_sections (inbfd, copy_sections, (PTR) outbfd);

  /* Finish up the header information.  */
  if (custom_file != NULL)
    {
      PTR data;

      data = xmalloc (custom_size);
      if (fread (data, 1, custom_size, custom_data) != custom_size)
	fprintf (stderr, "%s:%s: read: %s\n", program_name, custom_file,
		 strerror (errno));
      else
	{
	  if (! bfd_set_section_contents (outbfd, custom_section, data,
					  (file_ptr) 0, custom_size))
	    bfd_fatal ("custom section");
	  nlm_fixed_header (outbfd)->customDataOffset =
	    custom_section->filepos;
	  nlm_fixed_header (outbfd)->customDataSize = custom_size;
	}
      free (data);
    }
  if (! debug_info)
    {
      /* As a special hack, the backend recognizes a debugInfoOffset
	 of -1 to mean that it should not output any debugging
	 information.  This can not be handling by fiddling with the
	 symbol table because exported symbols appear in both the
	 export information and the debugging information.  */
      nlm_fixed_header (outbfd)->debugInfoOffset = (file_ptr) -1;
    }
  if (map_file != NULL)
    fprintf (stderr,
	     "%s: MAP and FULLMAP are not supported; try ld -M\n",
	     program_name);
  if (help_file != NULL)
    {
      PTR data;

      data = xmalloc (help_size);
      if (fread (data, 1, help_size, help_data) != help_size)
	fprintf (stderr, "%s:%s: read: %s\n", program_name, help_file,
		 strerror (errno));
      else
	{
	  if (! bfd_set_section_contents (outbfd, help_section, data,
					  (file_ptr) 0, help_size))
	    bfd_fatal ("help section");
	  nlm_extended_header (outbfd)->helpFileOffset =
	    help_section->filepos;
	  nlm_extended_header (outbfd)->helpFileLength = help_size;
	}
      free (data);
    }
  if (message_file != NULL)
    {
      PTR data;

      data = xmalloc (message_size);
      if (fread (data, 1, message_size, message_data) != message_size)
	fprintf (stderr, "%s:%s: read: %s\n", program_name, message_file,
		 strerror (errno));
      else
	{
	  if (! bfd_set_section_contents (outbfd, message_section, data,
					  (file_ptr) 0, message_size))
	    bfd_fatal ("message section");
	  nlm_extended_header (outbfd)->messageFileOffset =
	    message_section->filepos;
	  nlm_extended_header (outbfd)->messageFileLength = message_size;

	  /* FIXME: Are these offsets correct on all platforms?  Are
	     they 32 bits on all platforms?  What endianness?  */
	  nlm_extended_header (outbfd)->languageID =
	    bfd_h_get_32 (outbfd, (bfd_byte *) data + 106);
	  nlm_extended_header (outbfd)->messageCount =
	    bfd_h_get_32 (outbfd, (bfd_byte *) data + 110);
	}
      free (data);
    }
  if (modules != NULL)
    {
      PTR data;
      unsigned char *set;
      struct string_list *l;
      bfd_size_type c;

      data = xmalloc (module_size);
      c = 0;
      set = (unsigned char *) data;
      for (l = modules; l != NULL; l = l->next)
	{
	  *set = strlen (l->string);
	  strncpy (set + 1, l->string, *set);
	  set += *set + 1;
	  ++c;
	}
      if (! bfd_set_section_contents (outbfd, module_section, data,
				      (file_ptr) 0, module_size))
	bfd_fatal ("module section");
      nlm_fixed_header (outbfd)->moduleDependencyOffset =
	module_section->filepos;
      nlm_fixed_header (outbfd)->numberOfModuleDependencies = c;
    }
  if (rpc_file != NULL)
    {
      PTR data;

      data = xmalloc (rpc_size);
      if (fread (data, 1, rpc_size, rpc_data) != rpc_size)
	fprintf (stderr, "%s:%s: read: %s\n", program_name, rpc_file,
		 strerror (errno));
      else
	{
	  if (! bfd_set_section_contents (outbfd, rpc_section, data,
					  (file_ptr) 0, rpc_size))
	    bfd_fatal ("rpc section");
	  nlm_extended_header (outbfd)->RPCDataOffset =
	    rpc_section->filepos;
	  nlm_extended_header (outbfd)->RPCDataLength = rpc_size;
	}
      free (data);
    }
  if (sharelib_file != NULL)
    {
      PTR data;

      data = xmalloc (shared_size);
      if (fseek (shared_data, shared_offset, SEEK_SET) != 0
	  || fread (data, 1, shared_size, shared_data) != shared_size)
	fprintf (stderr, "%s:%s: read: %s\n", program_name, sharelib_file,
		 strerror (errno));
      else
	{
	  if (! bfd_set_section_contents (outbfd, shared_section, data,
					  (file_ptr) 0, shared_size))
	    bfd_fatal ("shared section");
	}
      nlm_extended_header (outbfd)->sharedCodeOffset =
	sharedhdr.codeImageOffset - shared_offset + shared_section->filepos;
      nlm_extended_header (outbfd)->sharedCodeLength =
	sharedhdr.codeImageSize;
      nlm_extended_header (outbfd)->sharedDataOffset =
	sharedhdr.dataImageOffset - shared_offset + shared_section->filepos;
      nlm_extended_header (outbfd)->sharedDataLength =
	sharedhdr.dataImageSize;
      nlm_extended_header (outbfd)->sharedRelocationFixupOffset =
	(sharedhdr.relocationFixupOffset
	 - shared_offset
	 + shared_section->filepos);
      nlm_extended_header (outbfd)->sharedRelocationFixupCount =
	sharedhdr.numberOfRelocationFixups;
      nlm_extended_header (outbfd)->sharedExternalReferenceOffset =
	(sharedhdr.externalReferencesOffset
	 - shared_offset
	 + shared_section->filepos);
      nlm_extended_header (outbfd)->sharedExternalReferenceCount =
	sharedhdr.numberOfExternalReferences;
      nlm_extended_header (outbfd)->sharedPublicsOffset =
	sharedhdr.publicsOffset - shared_offset + shared_section->filepos;
      nlm_extended_header (outbfd)->sharedPublicsCount =
	sharedhdr.numberOfPublics;
      nlm_extended_header (outbfd)->sharedDebugRecordOffset =
	sharedhdr.debugInfoOffset - shared_offset + shared_section->filepos;
      nlm_extended_header (outbfd)->sharedDebugRecordCount =
	sharedhdr.numberOfDebugRecords;
      nlm_extended_header (outbfd)->SharedInitializationOffset =
	sharedhdr.codeStartOffset;
      nlm_extended_header (outbfd)->SharedExitProcedureOffset =
	sharedhdr.exitProcedureOffset;
      free (data);
    }
  len = strlen (output_file);
  if (len > NLM_MODULE_NAME_SIZE - 2)
    len = NLM_MODULE_NAME_SIZE - 2;
  nlm_fixed_header (outbfd)->moduleName[0] = len;

  strncpy (nlm_fixed_header (outbfd)->moduleName + 1, output_file,
	   NLM_MODULE_NAME_SIZE - 2);
  nlm_fixed_header (outbfd)->moduleName[NLM_MODULE_NAME_SIZE - 1] = '\0';
  for (modname = nlm_fixed_header (outbfd)->moduleName;
       *modname != '\0';
       modname++)
    if (islower (*modname))
      *modname = toupper (*modname);

  strncpy (nlm_variable_header (outbfd)->oldThreadName, " LONG",
	   NLM_OLD_THREAD_NAME_LENGTH);

  if (! bfd_close (outbfd))
    bfd_fatal (output_file);
  if (! bfd_close (inbfd))
    bfd_fatal (input_file);

  if (unlink_on_exit != NULL)
    unlink (unlink_on_exit);

  return 0;
}

/* Display a help message and exit.  */

static void
show_help ()
{
  printf ("%s: Convert an object file into a NetWare Loadable Module\n",
	  program_name);
  show_usage (stdout, 0);
}

/* Show a usage message and exit.  */

static void
show_usage (file, status)
     FILE *file;
     int status;
{
  fprintf (file, "\
Usage: %s [-dhV] [-I format] [-O format] [-T header-file] [-l linker]\n\
       [--input-format=format] [--output-format=format]\n\
       [--header-file=file] [--linker=linker] [--debug]\n\
       [--help] [--version]\n\
       [in-file [out-file]]\n",
	   program_name);
  exit (status);
}

/* Select the output format based on the input architecture, machine,
   and endianness.  This chooses the appropriate NLM target.  */

static const char *
select_output_format (arch, mach, bigendian)
     enum bfd_architecture arch;
     unsigned long mach;
     boolean bigendian;
{
  switch (arch)
    {
    case bfd_arch_i386:
      return "nlm32-i386";
    case bfd_arch_sparc:
      return "nlm32-sparc";
    case bfd_arch_alpha:
      return "nlm32-alpha";
    default:
      fprintf (stderr, "%s: no default NLM format for %s\n",
	       program_name, bfd_printable_arch_mach (arch, mach));
      exit (1);
      /* Avoid warning.  */
      return NULL;
    }
  /*NOTREACHED*/
}

/* The BFD sections are copied in two passes.  This function selects
   the output section for each input section, and sets up the section
   name, size, etc.  */

static void
setup_sections (inbfd, insec, data_ptr)
     bfd *inbfd;
     asection *insec;
     PTR data_ptr;
{
  bfd *outbfd = (bfd *) data_ptr;
  flagword f;
  const char *outname;
  asection *outsec;

  /* FIXME: We don't want to copy the .reginfo section of an ECOFF
     file.  However, I don't have a good way to describe this section.
     We do want to copy the section when using objcopy.  */
  if (bfd_get_flavour (inbfd) == bfd_target_ecoff_flavour
      && strcmp (bfd_section_name (inbfd, insec), ".reginfo") == 0)
    return;

  f = bfd_get_section_flags (inbfd, insec);
  if (f & SEC_CODE)
    outname = NLM_CODE_NAME;
  else if ((f & SEC_LOAD) && (f & SEC_HAS_CONTENTS))
    outname = NLM_INITIALIZED_DATA_NAME;
  else if (f & SEC_ALLOC)
    outname = NLM_UNINITIALIZED_DATA_NAME;
  else
    outname = bfd_section_name (inbfd, insec);

  outsec = bfd_get_section_by_name (outbfd, outname);
  if (outsec == NULL)
    {
      outsec = bfd_make_section (outbfd, outname);
      if (outsec == NULL)
	bfd_fatal ("make section");
    }

  insec->output_section = outsec;
  insec->output_offset = bfd_section_size (outbfd, outsec);

  if (! bfd_set_section_size (outbfd, outsec,
			      (bfd_section_size (outbfd, outsec)
			       + bfd_section_size (inbfd, insec))))
    bfd_fatal ("set section size");

  if ((bfd_section_alignment (inbfd, insec)
       > bfd_section_alignment (outbfd, outsec))
      && ! bfd_set_section_alignment (outbfd, outsec,
				      bfd_section_alignment (inbfd, insec)))
    bfd_fatal ("set section alignment");

  if (! bfd_set_section_flags (outbfd, outsec, f))
    bfd_fatal ("set section flags");

  bfd_set_reloc (outbfd, outsec, (arelent **) NULL, 0);
}

/* Copy the section contents.  */

static void
copy_sections (inbfd, insec, data_ptr)
     bfd *inbfd;
     asection *insec;
     PTR data_ptr;
{
  bfd *outbfd = (bfd *) data_ptr;
  asection *outsec;
  bfd_size_type size;
  PTR contents;
  bfd_size_type reloc_size;

  /* FIXME: We don't want to copy the .reginfo section of an ECOFF
     file.  However, I don't have a good way to describe this section.
     We do want to copy the section when using objcopy.  */
  if (bfd_get_flavour (inbfd) == bfd_target_ecoff_flavour
      && strcmp (bfd_section_name (inbfd, insec), ".reginfo") == 0)
    return;

  outsec = insec->output_section;
  assert (outsec != NULL);

  size = bfd_get_section_size_before_reloc (insec);
  if (size == 0)
    return;

  /* FIXME: Why are these necessary?  */
  insec->_cooked_size = insec->_raw_size;
  insec->reloc_done = true;

  if ((bfd_get_section_flags (inbfd, insec) & SEC_HAS_CONTENTS) == 0)
    contents = NULL;
  else
    {
      contents = xmalloc (size);
      if (! bfd_get_section_contents (inbfd, insec, contents,
				      (file_ptr) 0, size))
	bfd_fatal (bfd_get_filename (inbfd));
    }

  reloc_size = bfd_get_reloc_upper_bound (inbfd, insec);
  if (reloc_size != 0)
    {
      arelent **relocs;
      bfd_size_type reloc_count;

      relocs = (arelent **) xmalloc (reloc_size);
      reloc_count = bfd_canonicalize_reloc (inbfd, insec, relocs, symbols);
      mangle_relocs (outbfd, insec, &relocs, &reloc_count, (char *) contents,
		     size);

      /* FIXME: refers to internal BFD fields.  */
      if (outsec->orelocation != (arelent **) NULL)
	{
	  bfd_size_type total_count;
	  arelent **combined;

	  total_count = reloc_count + outsec->reloc_count;
	  combined = (arelent **) xmalloc (total_count * sizeof (arelent));
	  memcpy (combined, outsec->orelocation,
		  outsec->reloc_count * sizeof (arelent));
	  memcpy (combined + outsec->reloc_count, relocs,
		  (size_t) (reloc_count * sizeof (arelent)));
	  free (outsec->orelocation);
	  reloc_count = total_count;
	  relocs = combined;
	}

      bfd_set_reloc (outbfd, outsec, relocs, reloc_count);
    }

  if (contents != NULL)
    {
      if (! bfd_set_section_contents (outbfd, outsec, contents,
				      insec->output_offset, size))
	bfd_fatal (bfd_get_filename (outbfd));
      free (contents);
    }
}

/* Some, perhaps all, NetWare targets require changing the relocs used
   by the input formats.  */

static void
mangle_relocs (outbfd, insec, relocs_ptr, reloc_count_ptr, contents,
	       contents_size)
     bfd *outbfd;
     asection *insec;
     arelent ***relocs_ptr;
     bfd_size_type *reloc_count_ptr;
     char *contents;
     bfd_size_type contents_size;
{
  switch (bfd_get_arch (outbfd))
    {
    case bfd_arch_i386:
      i386_mangle_relocs (outbfd, insec, relocs_ptr, reloc_count_ptr,
			  contents, contents_size);
      break;
    case bfd_arch_alpha:
      alpha_mangle_relocs (outbfd, insec, relocs_ptr, reloc_count_ptr,
			   contents, contents_size);
      break;
    default:
      default_mangle_relocs (outbfd, insec, relocs_ptr, reloc_count_ptr,
			     contents, contents_size);
      break;
    }
}

/* By default all we need to do for relocs is change the address by
   the output_offset.  */

/*ARGSUSED*/
static void
default_mangle_relocs (outbfd, insec, relocs_ptr, reloc_count_ptr, contents,
		       contents_size)
     bfd *outbfd;
     asection *insec;
     arelent ***relocs_ptr;
     bfd_size_type *reloc_count_ptr;
     char *contents;
     bfd_size_type contents_size;
{
  if (insec->output_offset != 0)
    {
      bfd_size_type reloc_count;
      register arelent **relocs;
      register bfd_size_type i;

      reloc_count = *reloc_count_ptr;
      relocs = *relocs_ptr;
      for (i = 0; i < reloc_count; i++, relocs++)
	(*relocs)->address += insec->output_offset;
    }
}

/* NetWare on the i386 supports a restricted set of relocs, which are
   different from those used on other i386 targets.  This routine
   converts the relocs.  It is, obviously, very target dependent.  At
   the moment, the nlm32-i386 backend performs similar translations;
   however, it is more reliable and efficient to do them here.  */

static reloc_howto_type nlm_i386_pcrel_howto =
  HOWTO (1,			/* type */
	 0,			/* rightshift */
	 2,			/* size (0 = byte, 1 = short, 2 = long) */
	 32,			/* bitsize */
	 true,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_signed, /* complain_on_overflow */
	 0,			/* special_function */
	 "DISP32",		/* name */
	 true,			/* partial_inplace */
	 0xffffffff,		/* src_mask */
	 0xffffffff,		/* dst_mask */
	 true);			/* pcrel_offset */

static void
i386_mangle_relocs (outbfd, insec, relocs_ptr, reloc_count_ptr, contents,
		    contents_size)
     bfd *outbfd;
     asection *insec;
     arelent ***relocs_ptr;
     bfd_size_type *reloc_count_ptr;
     char *contents;
     bfd_size_type contents_size;
{
  bfd_size_type reloc_count, i;
  arelent **relocs;

  reloc_count = *reloc_count_ptr;
  relocs = *relocs_ptr;
  for (i = 0; i < reloc_count; i++)
    {
      arelent *rel;
      asymbol *sym;
      bfd_size_type address;
      bfd_vma addend;

      rel = *relocs++;
      sym = *rel->sym_ptr_ptr;

      /* We're moving the relocs from the input section to the output
	 section, so we must adjust the address accordingly.  */
      address = rel->address;
      rel->address += insec->output_offset;

      /* Note that no serious harm will ensue if we fail to change a
	 reloc.  The backend will fail when writing out the reloc.  */

      /* Make sure this reloc is within the data we have.  We use only
	 4 byte relocs here, so we insist on having 4 bytes.  */
      if (address + 4 > contents_size)
	continue;

      /* A PC relative reloc entirely within a single section is
	 completely unnecessary.  This can be generated by ld -r.  */
      if (sym == insec->symbol
	  && rel->howto != NULL
	  && rel->howto->pc_relative
	  && ! rel->howto->pcrel_offset)
	{
	  --*reloc_count_ptr;
	  --relocs;
	  memmove (relocs, relocs + 1,
		   (size_t) ((reloc_count - i) * sizeof (arelent *)));
	  continue;
	}

      /* Get the amount the relocation will add in.  */
      addend = rel->addend + sym->value;

      /* NetWare doesn't support PC relative relocs against defined
	 symbols, so we have to eliminate them by doing the relocation
	 now.  We can only do this if the reloc is within a single
	 section.  */
      if (rel->howto != NULL
	  && rel->howto->pc_relative
	  && bfd_get_section (sym) == insec->output_section)
	{
	  bfd_vma val;

	  if (rel->howto->pcrel_offset)
	    addend -= address;

	  val = bfd_get_32 (outbfd, (bfd_byte *) contents + address);
	  val += addend;
	  bfd_put_32 (outbfd, val, (bfd_byte *) contents + address);

	  --*reloc_count_ptr;
	  --relocs;
	  memmove (relocs, relocs + 1,
		   (size_t) ((reloc_count - i) * sizeof (arelent *)));
	  continue;
	}

      /* NetWare doesn't support reloc addends, so we get rid of them
	 here by simply adding them into the object data.  We handle
	 the symbol value, if any, the same way.  */
      if (addend != 0
	  && rel->howto != NULL
	  && rel->howto->rightshift == 0
	  && rel->howto->size == 2
	  && rel->howto->bitsize == 32
	  && rel->howto->bitpos == 0
	  && rel->howto->src_mask == 0xffffffff
	  && rel->howto->dst_mask == 0xffffffff)
	{
	  bfd_vma val;

	  val = bfd_get_32 (outbfd, (bfd_byte *) contents + address);
	  val += addend;
	  bfd_put_32 (outbfd, val, (bfd_byte *) contents + address);

	  /* Adjust the reloc for the changes we just made.  */
	  rel->addend = 0;
	  if (bfd_get_section (sym) != &bfd_und_section)
	    rel->sym_ptr_ptr = bfd_get_section (sym)->symbol_ptr_ptr;
	}

      /* NetWare uses a reloc with pcrel_offset set.  We adjust
	 pc_relative relocs accordingly.  We are going to change the
	 howto field, so we can only do this if the current one is
	 compatible.  We should check that special_function is NULL
	 here, but at the moment coff-i386 uses a special_function
	 which does not affect what we are doing here.  */
      if (rel->howto != NULL
	  && rel->howto->pc_relative
	  && ! rel->howto->pcrel_offset
	  && rel->howto->rightshift == 0
	  && rel->howto->size == 2
	  && rel->howto->bitsize == 32
	  && rel->howto->bitpos == 0
	  && rel->howto->src_mask == 0xffffffff
	  && rel->howto->dst_mask == 0xffffffff)
	{
	  bfd_vma val;

	  /* When pcrel_offset is not set, it means that the negative
	     of the address of the memory location is stored in the
	     memory location.  We must add it back in.  */
	  val = bfd_get_32 (outbfd, (bfd_byte *) contents + address);
	  val += address;
	  bfd_put_32 (outbfd, val, (bfd_byte *) contents + address);

	  /* We must change to a new howto.  */
	  rel->howto = &nlm_i386_pcrel_howto;
	}
    }
}

/* On the Alpha the first reloc for every section must be a special
   relocs which hold the GP address.  Also, the first reloc in the
   file must be a special reloc which holds the address of the .lita
   section.  */

static reloc_howto_type nlm32_alpha_nw_howto =
  HOWTO (ALPHA_R_NW_RELOC,	/* type */
	 0,			/* rightshift */
	 0,			/* size (0 = byte, 1 = short, 2 = long) */
	 0,			/* bitsize */
	 false,			/* pc_relative */
	 0,			/* bitpos */
	 complain_overflow_dont, /* complain_on_overflow */
	 0,			/* special_function */
	 "NW_RELOC",		/* name */
	 false,			/* partial_inplace */
	 0,			/* src_mask */
	 0,			/* dst_mask */
	 false);		/* pcrel_offset */

/*ARGSUSED*/
static void
alpha_mangle_relocs (outbfd, insec, relocs_ptr, reloc_count_ptr, contents,
		     contents_size)
     bfd *outbfd;
     asection *insec;
     register arelent ***relocs_ptr;
     bfd_size_type *reloc_count_ptr;
     char *contents;
     bfd_size_type contents_size;
{
  bfd_size_type old_reloc_count;
  arelent **old_relocs;
  register arelent **relocs;

  old_reloc_count = *reloc_count_ptr;
  old_relocs = *relocs_ptr;
  relocs = (arelent **) xmalloc ((old_reloc_count + 3) * sizeof (arelent *));
  *relocs_ptr = relocs;

  if (nlm_alpha_backend_data (outbfd)->lita_address == 0)
    {
      bfd *inbfd;
      asection *lita_section;

      inbfd = insec->owner;
      lita_section = bfd_get_section_by_name (inbfd, _LITA);
      if (lita_section != (asection *) NULL)
	{
	  nlm_alpha_backend_data (outbfd)->lita_address =
	    bfd_get_section_vma (inbfd, lita_section);
	  nlm_alpha_backend_data (outbfd)->lita_size =
	    bfd_section_size (inbfd, lita_section);
	}
      else
	{
	  /* Avoid outputting this reloc again.  */
	  nlm_alpha_backend_data (outbfd)->lita_address = 4;
	}

      *relocs = (arelent *) xmalloc (sizeof (arelent));
      (*relocs)->sym_ptr_ptr = bfd_abs_section.symbol_ptr_ptr;
      (*relocs)->address = nlm_alpha_backend_data (outbfd)->lita_address;
      (*relocs)->addend = nlm_alpha_backend_data (outbfd)->lita_size + 1;
      (*relocs)->howto = &nlm32_alpha_nw_howto;
      ++relocs;
      ++(*reloc_count_ptr);
    }

  /* Get the GP value from bfd.  It is in the .reginfo section.  */
  if (nlm_alpha_backend_data (outbfd)->gp == 0)
    {
      bfd *inbfd;
      asection *reginfo_sec;
      struct ecoff_reginfo sreginfo;

      inbfd = insec->owner;
      assert (bfd_get_flavour (inbfd) == bfd_target_ecoff_flavour);
      reginfo_sec = bfd_get_section_by_name (inbfd, REGINFO);
      if (reginfo_sec != (asection *) NULL
	  && bfd_get_section_contents (inbfd, reginfo_sec,
				       (PTR) &sreginfo, (file_ptr) 0,
				       sizeof sreginfo) != false)
	nlm_alpha_backend_data (outbfd)->gp = sreginfo.gp_value;
    }

  *relocs = (arelent *) xmalloc (sizeof (arelent));
  (*relocs)->sym_ptr_ptr = bfd_abs_section.symbol_ptr_ptr;
  (*relocs)->address = nlm_alpha_backend_data (outbfd)->gp;
  (*relocs)->addend = 0;
  (*relocs)->howto = &nlm32_alpha_nw_howto;
  ++relocs;
  ++(*reloc_count_ptr);

  memcpy ((PTR) relocs, (PTR) old_relocs,
	  (size_t) old_reloc_count * sizeof (arelent *));
  relocs[old_reloc_count] = (arelent *) NULL;

  free (old_relocs);

  if (insec->output_offset != 0)
    {
      register bfd_size_type i;

      for (i = 0; i < old_reloc_count; i++, relocs++)
	(*relocs)->address += insec->output_offset;
    }
}

/* Name of linker.  */
#ifndef LD_NAME
#define LD_NAME "ld"
#endif

/* Temporary file name base.  */
static char *temp_filename;

/* The user has specified several input files.  Invoke the linker to
   link them all together, and convert and delete the resulting output
   file.  */

static char *
link_inputs (inputs, ld)
     struct string_list *inputs;
     char *ld;
{
  size_t c;
  struct string_list *q;
  char **argv;
  size_t i;
  int pid;
  int status;

  c = 0;
  for (q = inputs; q != NULL; q = q->next)
    ++c;

  argv = (char **) alloca (c + 5);

#ifndef __MSDOS__
  if (ld == NULL)
    {
      char *p;

      /* Find the linker to invoke based on how nlmconv was run.  */
      p = program_name + strlen (program_name);
      while (p != program_name)
	{
	  if (p[-1] == '/')
	    {
	      ld = (char *) xmalloc (p - program_name + strlen (LD_NAME) + 1);
	      memcpy (ld, program_name, p - program_name);
	      strcpy (ld + (p - program_name), LD_NAME);
	      break;
	    }
	  --p;
	}
    }
#endif

  if (ld == NULL)
    ld = (char *) LD_NAME;

  choose_temp_base ();

  unlink_on_exit = xmalloc (strlen (temp_filename) + 3);
  sprintf (unlink_on_exit, "%s.O", temp_filename);

  argv[0] = ld;
  argv[1] = (char *) "-r";
  argv[2] = (char *) "-o";
  argv[3] = unlink_on_exit;
  i = 4;
  for (q = inputs; q != NULL; q = q->next, i++)
    argv[i] = q->string;
  argv[i] = NULL;

  if (debug)
    {
      for (i = 0; argv[i] != NULL; i++)
	fprintf (stderr, " %s", argv[i]);
      fprintf (stderr, "\n");
    }

  pid = pexecute (ld, argv);

  if (waitpid (pid, &status, 0) < 0)
    {
      perror ("waitpid");
      unlink (unlink_on_exit);
      exit (1);
    }

  if (status != 0)
    {
      fprintf (stderr, "%s: Execution of %s failed\n", program_name, ld);
      unlink (unlink_on_exit);
      exit (1);
    }

  return unlink_on_exit;
}

/* Choose a temporary file name.  Stolen from gcc.c.  */

static const char *
choose_temp_base_try (try, base)
     const char *try;
     const char *base;
{
  const char *rv;

  if (base)
    rv = base;
  else if (try == NULL)
    rv = NULL;
  else if (access (try, R_OK | W_OK) != 0)
    rv = NULL;
  else
    rv = try;
  return rv;
}

static void
choose_temp_base ()
{
  const char *base = NULL;
  int len;

  base = choose_temp_base_try (getenv ("TMPDIR"), base);
  base = choose_temp_base_try (getenv ("TMP"), base);
  base = choose_temp_base_try (getenv ("TEMP"), base);

#ifdef P_tmpdir
  base = choose_temp_base_try (P_tmpdir, base);
#endif

  base = choose_temp_base_try ("/usr/tmp", base);
  base = choose_temp_base_try ("/tmp", base);

  /* If all else fails, use the current directory! */  
  if (base == NULL)
    base = "./";

  len = strlen (base);
  temp_filename = xmalloc (len + sizeof("/ccXXXXXX") + 1);
  strcpy (temp_filename, base);
  if (len > 0 && temp_filename[len-1] != '/')
    temp_filename[len++] = '/';
  strcpy (temp_filename + len, "ccXXXXXX");

  mktemp (temp_filename);
  if (*temp_filename == '\0')
    abort ();
}

/* Execute a job.  Stolen from gcc.c.  */

#ifndef OS2
#ifdef __MSDOS__

static int
pexecute (program, argv)
     char *program;
     char *argv[];
{
  char *scmd, *rf;
  FILE *argfile;
  int i;

  scmd = (char *)malloc (strlen (program) + strlen (temp_filename) + 10);
  rf = scmd + strlen(program) + 2 + el;
  sprintf (scmd, "%s.exe @%s.gp", program, temp_filename);
  argfile = fopen (rf, "w");
  if (argfile == 0)
    pfatal_with_name (rf);

  for (i=1; argv[i]; i++)
    {
      char *cp;
      for (cp = argv[i]; *cp; cp++)
	{
	  if (*cp == '"' || *cp == '\'' || *cp == '\\' || isspace (*cp))
	    fputc ('\\', argfile);
	  fputc (*cp, argfile);
	}
      fputc ('\n', argfile);
    }
  fclose (argfile);

  i = system (scmd);

  remove (rf);
  
  if (i == -1)
    {
      perror (program);
      return MIN_FATAL_STATUS << 8;
    }

  return i << 8;
}

#else /* not __MSDOS__ */

static int
pexecute (program, argv)
     char *program;
     char *argv[];
{
  int pid;
  int retries, sleep_interval;

  /* Fork a subprocess; wait and retry if it fails.  */
  sleep_interval = 1;
  for (retries = 0; retries < 4; retries++)
    {
      pid = vfork ();
      if (pid >= 0)
	break;
      sleep (sleep_interval);
      sleep_interval *= 2;
    }

  switch (pid)
    {
    case -1:
#ifdef vfork
      perror ("fork");
#else
      perror ("vfork");
#endif
      exit (1);
      /* NOTREACHED */
      return 0;

    case 0: /* child */
      /* Exec the program.  */
      execvp (program, argv);
      perror (program);
      exit (1);
      /* NOTREACHED */
      return 0;

    default:
      /* Return child's process number.  */
      return pid;
    }
}

#endif /* not __MSDOS__ */
#else /* not OS2 */

static int
pexecute (program, argv)
     char *program;
     char *argv[];
{
  return spawnvp (1, program, argv);
}
#endif /* not OS2 */