collect2.c

/* Collect static initialization info into data structures
   that can be traversed by C++ initialization and finalization
   routines.

   Copyright (C) 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
   Contributed by Chris Smith (csmith@convex.com).
   Heavily modified by Michael Meissner (meissner@cygnus.com),
   Per Bothner (bothner@cygnus.com), and John Gilmore (gnu@cygnus.com).

This file is part of GNU CC.

GNU CC 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, or (at your option)
any later version.

GNU CC 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 GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */


/* Build tables of static constructors and destructors and run ld. */

#include "config.h"
#include <sys/types.h>
#include <stdio.h>
#include <ctype.h>
#include <errno.h>
#include <signal.h>
#include <sys/file.h>
#include <sys/stat.h>
#ifdef NO_WAIT_H
#include <sys/wait.h>
#endif

#define COLLECT

#include "demangle.h"
#include "obstack.h"

#ifndef errno
extern int errno;
#endif

#ifndef HAVE_STRERROR
#if defined(bsd4_4) 
extern const char *const sys_errlist[];
#else
extern char *sys_errlist[];
#endif
extern int sys_nerr;
#else
char *strerror();
#endif

/* Obstack allocation and deallocation routines.  */
#define obstack_chunk_alloc xmalloc
#define obstack_chunk_free free

#if !defined (__STDC__) && !defined (const)
#define const
#endif

#ifdef USG
#define vfork fork
#endif

/* Add prototype support.  */
#ifndef PROTO
#if defined (USE_PROTOTYPES) ? USE_PROTOTYPES : defined (__STDC__)
#define PROTO(ARGS) ARGS
#else
#define PROTO(ARGS) ()
#endif
#endif

#ifndef R_OK
#define R_OK 4
#define W_OK 2
#define X_OK 1
#endif

#ifndef WIFSIGNALED
#define WIFSIGNALED(S) (((S) & 0xff) != 0 && ((S) & 0xff) != 0x7f)
#endif
#ifndef WTERMSIG
#define WTERMSIG(S) ((S) & 0x7f)
#endif
#ifndef WIFEXITED
#define WIFEXITED(S) (((S) & 0xff) == 0)
#endif
#ifndef WEXITSTATUS
#define WEXITSTATUS(S) (((S) & 0xff00) >> 8)
#endif

/* On MSDOS, write temp files in current dir
   because there's no place else we can expect to use.  */
#ifdef __MSDOS__
#ifndef P_tmpdir
#define P_tmpdir "./"
#endif
#endif

/* On certain systems, we have code that works by scanning the object file
   directly.  But this code uses system-specific header files and library
   functions, so turn it off in a cross-compiler.  Likewise, the names of
   the utilities aren't correct for a cross-compiler; we have to hope that
   cross-versions are in the proper directories.  */

#ifdef CROSS_COMPILE
#undef SUNOS4_SHARED_LIBRARIES
#undef OBJECT_FORMAT_COFF
#undef OBJECT_FORMAT_ROSE
#undef MD_EXEC_PREFIX
#undef REAL_LD_FILE_NAME
#undef REAL_NM_FILE_NAME
#undef REAL_STRIP_FILE_NAME
#endif

/* If we can't use a special method, use the ordinary one:
   run nm to find what symbols are present.
   In a cross-compiler, this means you need a cross nm,
   but that isn't quite as unpleasant as special headers.  */

#if !defined (OBJECT_FORMAT_COFF) && !defined (OBJECT_FORMAT_ROSE)
#define OBJECT_FORMAT_NONE
#endif

#ifdef OBJECT_FORMAT_COFF

#include <a.out.h>
#include <ar.h>

#ifdef UMAX
#include <sgs.h>
#endif

/* Many versions of ldfcn.h define these.  */
#ifdef FREAD
#undef FREAD
#undef FWRITE
#endif

#include <ldfcn.h>

/* Some systems have an ISCOFF macro, but others do not.  In some cases
   the macro may be wrong.  MY_ISCOFF is defined in tm.h files for machines
   that either do not have an ISCOFF macro in /usr/include or for those 
   where it is wrong.  */

#ifndef MY_ISCOFF
#define MY_ISCOFF(X) ISCOFF (X)
#endif

#ifdef XCOFF_DEBUGGING_INFO
#define XCOFF_SCAN_LIBS
#endif

#endif /* OBJECT_FORMAT_COFF */

#ifdef OBJECT_FORMAT_ROSE

#ifdef _OSF_SOURCE
#define USE_MMAP
#endif

#ifdef USE_MMAP
#include <sys/mman.h>
#endif

#include <unistd.h>
#include <mach_o_format.h>
#include <mach_o_header.h>
#include <mach_o_vals.h>
#include <mach_o_types.h>

#endif /* OBJECT_FORMAT_ROSE */

#ifdef OBJECT_FORMAT_NONE

/* Default flags to pass to nm.  */
#ifndef NM_FLAGS
#define NM_FLAGS "-p"
#endif

#endif /* OBJECT_FORMAT_NONE */

/* Some systems use __main in a way incompatible with its use in gcc, in these
   cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
   give the same symbol without quotes for an alternative entry point.  You
   must define both, or neither.  */
#ifndef NAME__MAIN
#define NAME__MAIN "__main"
#define SYMBOL__MAIN __main
#endif

#if defined (LDD_SUFFIX) || SUNOS4_SHARED_LIBRARIES || defined(XCOFF_SCAN_LIBS)
#define SCAN_LIBRARIES
#endif

#ifdef USE_COLLECT2
int do_collecting = 1;
#else
int do_collecting = 0;
#endif

/* Linked lists of constructor and destructor names. */

struct id 
{
  struct id *next;
  int sequence;
  char name[1];
};

struct head
{
  struct id *first;
  struct id *last;
  int number;
};

/* Enumeration giving which pass this is for scanning the program file.  */

enum pass {
  PASS_FIRST,				/* without constructors */
  PASS_OBJ,				/* individual objects */
  PASS_LIB,			        /* looking for shared libraries */
  PASS_SECOND				/* with constructors linked in */
};

#ifndef NO_SYS_SIGLIST
#ifndef DONT_DECLARE_SYS_SIGLIST
extern char *sys_siglist[];
#endif
#endif
extern char *version_string;

int vflag;				/* true if -v */
static int rflag;			/* true if -r */
static int strip_flag;			/* true if -s */

int debug;				/* true if -debug */

static int shared_obj;		        /* true if -shared */

static int   temp_filename_length;	/* Length of temp_filename */
static char *temp_filename;		/* Base of temp filenames */
static char *c_file;			/* <xxx>.c for constructor/destructor list. */
static char *o_file;			/* <xxx>.o for constructor/destructor list. */
static char *export_file;	        /* <xxx>.x for AIX export list. */
static int  auto_export = 1;	        /* true if exporting everything. */
char *ldout;				/* File for ld errors.  */
static char *output_file;		/* Output file for ld.  */
static char *nm_file_name;		/* pathname of nm */
static char *ldd_file_name;		/* pathname of ldd (or equivalent) */
static char *strip_file_name;		/* pathname of strip */
char *c_file_name;		        /* pathname of gcc */
static char *initname, *fininame;	/* names of init and fini funcs */

static struct head constructors;	/* list of constructors found */
static struct head destructors;		/* list of destructors found */
static struct head exports;		/* list of exported symbols */

struct obstack temporary_obstack;
struct obstack permanent_obstack;
char * temporary_firstobj;

/* Defined in the automatically-generated underscore.c.  */
extern int prepends_underscore;

extern char *getenv ();
extern char *mktemp ();
extern FILE *fdopen ();

/* Structure to hold all the directories in which to search for files to
   execute.  */

struct prefix_list
{
  char *prefix;               /* String to prepend to the path. */
  struct prefix_list *next;   /* Next in linked list. */
};

struct path_prefix
{
  struct prefix_list *plist;  /* List of prefixes to try */
  int max_len;                /* Max length of a prefix in PLIST */
  char *name;                 /* Name of this list (used in config stuff) */
};

void collect_exit		PROTO((int));
void collect_execute		PROTO((char *, char **, char *));
void dump_file			PROTO((char *));
static void handler		PROTO((int));
static int is_ctor_dtor		PROTO((char *));
static void choose_temp_base	PROTO((void));
static int is_in_prefix_list	PROTO((struct path_prefix *, char *, int));
static char *find_a_file	PROTO((struct path_prefix *, char *));
static void add_prefix		PROTO((struct path_prefix *, char *));
static void prefix_from_env	PROTO((char *, struct path_prefix *));
static void prefix_from_string	PROTO((char *, struct path_prefix *));
static void do_wait		PROTO((char *));
static void fork_execute	PROTO((char *, char **));
static void maybe_unlink	PROTO((char *));
static void add_to_list		PROTO((struct head *, char *));
static void write_list		PROTO((FILE *, char *, struct id *));
static void write_list_with_asm PROTO((FILE *, char *, struct id *));
static void write_c_file	PROTO((FILE *, char *));
static void write_export_file	PROTO((FILE *));
static void scan_prog_file	PROTO((char *, enum pass));
static void scan_libraries	PROTO((char *));

char *xcalloc ();
char *xmalloc ();

extern char *index ();
extern char *rindex ();
extern void free ();

#ifdef NO_DUP2
int
dup2 (oldfd, newfd)
     int oldfd;
     int newfd;
{
  int fdtmp[256];
  int fdx = 0;
  int fd;
 
  if (oldfd == newfd)
    return oldfd;
  close (newfd);
  while ((fd = dup (oldfd)) != newfd && fd >= 0) /* good enough for low fd's */
    fdtmp[fdx++] = fd;
  while (fdx > 0)
    close (fdtmp[--fdx]);

  return fd;
}
#endif

char *
my_strerror (e)
     int e;
{

#ifdef HAVE_STRERROR
  return strerror (e);

#else

  static char buffer[30];
  if (!e)
    return "";

  if (e > 0 && e < sys_nerr)
    return sys_errlist[e];

  sprintf (buffer, "Unknown error %d", e);
  return buffer;
#endif
}

/* Delete tempfiles and exit function.  */

void
collect_exit (status)
     int status;
{
  if (c_file != 0 && c_file[0])
    maybe_unlink (c_file);

  if (o_file != 0 && o_file[0])
    maybe_unlink (o_file);

  if (export_file != 0 && export_file[0])
    maybe_unlink (export_file);

  if (ldout != 0 && ldout[0])
    {
      dump_file (ldout);
      maybe_unlink (ldout);
    }

  if (status != 0 && output_file != 0 && output_file[0])
    maybe_unlink (output_file);

  exit (status);
}


/* Die when sys call fails. */

void
fatal_perror (string, arg1, arg2, arg3)
     char *string, *arg1, *arg2, *arg3;
{
  int e = errno;

  fprintf (stderr, "collect2: ");
  fprintf (stderr, string, arg1, arg2, arg3);
  fprintf (stderr, ": %s\n", my_strerror (e));
  collect_exit (1);
}

/* Just die. */

void
fatal (string, arg1, arg2, arg3)
     char *string, *arg1, *arg2, *arg3;
{
  fprintf (stderr, "collect2: ");
  fprintf (stderr, string, arg1, arg2, arg3);
  fprintf (stderr, "\n");
  collect_exit (1);
}

/* Write error message.  */

void
error (string, arg1, arg2, arg3, arg4)
     char *string, *arg1, *arg2, *arg3, *arg4;
{
  fprintf (stderr, "collect2: ");
  fprintf (stderr, string, arg1, arg2, arg3, arg4);
  fprintf (stderr, "\n");
}

/* In case obstack is linked in, and abort is defined to fancy_abort,
   provide a default entry.  */

void
fancy_abort ()
{
  fatal ("internal error");
}


static void
handler (signo)
     int signo;
{
  if (c_file != 0 && c_file[0])
    maybe_unlink (c_file);

  if (o_file != 0 && o_file[0])
    maybe_unlink (o_file);

  if (ldout != 0 && ldout[0])
    maybe_unlink (ldout);

  signal (signo, SIG_DFL);
  kill (getpid (), signo);
}


char *
xcalloc (size1, size2)
     int size1, size2;
{
  char *ptr = (char *) calloc (size1, size2);
  if (ptr)
    return ptr;

  fatal ("out of memory");
  return (char *)0;
}

char *
xmalloc (size)
     unsigned size;
{
  char *ptr = (char *) malloc (size);
  if (ptr)
    return ptr;

  fatal ("out of memory");
  return (char *)0;
}

char *
xrealloc (ptr, size)
     char *ptr;
     unsigned size;
{
  register char *value = (char *) realloc (ptr, size);
  if (value == 0)
    fatal ("virtual memory exhausted");
  return value;
}

int
file_exists (name)
     char *name;
{
  return access (name, R_OK) == 0;
}

/* Make a copy of a string INPUT with size SIZE.  */

char *
savestring (input, size)
     char *input;
     int size;
{
  char *output = (char *) xmalloc (size + 1);
  bcopy (input, output, size);
  output[size] = 0;
  return output;
}

void
dump_file (name)
     char *name;
{
  FILE *stream = fopen (name, "r");
  int no_demangle = !! getenv ("COLLECT_NO_DEMANGLE");

  if (stream == 0)
    return;
  while (1)
    {
      int c;
      while (c = getc (stream),
	     c != EOF && (isalnum (c) || c == '_' || c == '$' || c == '.'))
	obstack_1grow (&temporary_obstack, c);
      if (obstack_object_size (&temporary_obstack) > 0)
	{
	  char *word, *p, *result;
	  obstack_1grow (&temporary_obstack, '\0');
	  word = obstack_finish (&temporary_obstack);

	  if (*word == '.')
	    ++word, putc ('.', stderr);
	  p = word;
	  if (*p == '_' && prepends_underscore)
	    ++p;

	  if (no_demangle)
	    result = 0;
	  else
	    result = cplus_demangle (p, DMGL_PARAMS | DMGL_ANSI);

	  if (result)
	    {
	      int diff;
	      fputs (result, stderr);

	      diff = strlen (word) - strlen (result);
	      while (diff > 0)
		--diff, putc (' ', stderr);
	      while (diff < 0 && c == ' ')
		++diff, c = getc (stream);

	      free (result);
	    }
	  else
	    fputs (word, stderr);

	  fflush (stderr);
	  obstack_free (&temporary_obstack, temporary_firstobj);
	}
      if (c == EOF)
	break;
      putc (c, stderr);
    }
}

/* Decide whether the given symbol is:
   a constructor (1), a destructor (2), or neither (0).  */

static int
is_ctor_dtor (s)
     char *s;
{
  struct names { char *name; int len; int ret; int two_underscores; };

  register struct names *p;
  register int ch;
  register char *orig_s = s;

  static struct names special[] = {
#ifdef NO_DOLLAR_IN_LABEL
#ifdef NO_DOT_IN_LABEL
    { "GLOBAL__I_", sizeof ("GLOBAL__I_")-1, 1, 0 },
    { "GLOBAL__D_", sizeof ("GLOBAL__D_")-1, 2, 0 },
#else
    { "GLOBAL_.I.", sizeof ("GLOBAL_.I.")-1, 1, 0 },
    { "GLOBAL_.D.", sizeof ("GLOBAL_.D.")-1, 2, 0 },
#endif
#else
    { "GLOBAL_$I$", sizeof ("GLOBAL_$I$")-1, 1, 0 },
    { "GLOBAL_$D$", sizeof ("GLOBAL_$D$")-1, 2, 0 },
#endif
    { "GLOBAL__FI_", sizeof ("GLOBAL__FI_")-1, 3, 0 },
    { "GLOBAL__FD_", sizeof ("GLOBAL__FD_")-1, 4, 0 },
#ifdef CFRONT_LOSSAGE /* Don't collect cfront initialization functions.
			 cfront has its own linker procedure to collect them;
			 if collect2 gets them too, they get collected twice
			 when the cfront procedure is run and the compiler used
			 for linking happens to be GCC.  */
    { "sti__", sizeof ("sti__")-1, 1, 1 },
    { "std__", sizeof ("std__")-1, 2, 1 },
#endif /* CFRONT_LOSSAGE */
    { NULL, 0, 0, 0 }
  };

  while ((ch = *s) == '_')
    ++s;

  if (s == orig_s)
    return 0;

  for (p = &special[0]; p->len > 0; p++)
    {
      if (ch == p->name[0]
	  && (!p->two_underscores || ((s - orig_s) >= 2))
	  && strncmp(s, p->name, p->len) == 0)
	{
	  return p->ret;
	}
    }
  return 0;
}


/* Compute a string to use as the base of all temporary file names.
   It is substituted for %g.  */

static void
choose_temp_base ()
{
  char *base = getenv ("TMPDIR");
  int len;

  if (base == (char *)0)
    {
#ifdef P_tmpdir
      if (access (P_tmpdir, R_OK | W_OK) == 0)
	base = P_tmpdir;
#endif
      if (base == (char *)0)
	{
	  if (access ("/usr/tmp", R_OK | W_OK) == 0)
	    base = "/usr/tmp/";
	  else
	    base = "/tmp/";
	}
    }

  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);
  temp_filename_length = strlen (temp_filename);
}

/* Routine to add variables to the environment.  */

#ifndef HAVE_PUTENV

int
putenv (str)
     char *str;
{
#ifndef VMS			/* nor about VMS */

  extern char **environ;
  char **old_environ = environ;
  char **envp;
  int num_envs = 0;
  int name_len = 1;
  char *p = str;
  int ch;

  while ((ch = *p++) != '\0' && ch != '=')
    name_len++;

  if (!ch)
    abort ();

  /* Search for replacing an existing environment variable, and
     count the number of total environment variables.  */
  for (envp = old_environ; *envp; envp++)
    {
      num_envs++;
      if (!strncmp (str, *envp, name_len))
	{
	  *envp = str;
	  return 0;
	}
    }

  /* Add a new environment variable */
  environ = (char **) xmalloc (sizeof (char *) * (num_envs+2));
  *environ = str;
  bcopy ((char *) old_environ, (char *) (environ + 1),
	 sizeof (char *) * (num_envs+1));

  return 0;
#endif	/* VMS */
}

#endif	/* HAVE_PUTENV */

/* By default, colon separates directories in a path.  */
#ifndef PATH_SEPARATOR
#define PATH_SEPARATOR ':'
#endif

/* We maintain two prefix lists: one from COMPILER_PATH environment variable
   and one from the PATH variable.  */

static struct path_prefix cpath, path;

#ifdef CROSS_COMPILE
/* This is the name of the target machine.  We use it to form the name
   of the files to execute.  */

static char *target_machine = TARGET_MACHINE;
#endif

/* Names under which we were executed.  Never return one of those files in our
   searches.  */

static struct path_prefix our_file_names;

/* Determine if STRING is in PPREFIX.

   This utility is currently only used to look up file names.  Prefix lists
   record directory names.  This matters to us because the latter has a 
   trailing slash, so I've added a flag to handle both.  */

static int
is_in_prefix_list (pprefix, string, filep)
     struct path_prefix *pprefix;
     char *string;
     int filep;
{
  struct prefix_list *pl;

  if (filep)
    {
      int len = strlen (string);

      for (pl = pprefix->plist; pl; pl = pl->next)
	{
	  if (strncmp (pl->prefix, string, len) == 0
	      && strcmp (pl->prefix + len, "/") == 0)
	    return 1;
	}
    }
  else
    {
      for (pl = pprefix->plist; pl; pl = pl->next)
	{
	  if (strcmp (pl->prefix, string) == 0)
	    return 1;
	}
    }

  return 0;
}

/* Search for NAME using prefix list PPREFIX.  We only look for executable
   files. 

   Return 0 if not found, otherwise return its name, allocated with malloc. */

static char *
find_a_file (pprefix, name)
     struct path_prefix *pprefix;
     char *name;
{
  char *temp;
  struct prefix_list *pl;
  int len = pprefix->max_len + strlen (name) + 1;

#ifdef EXECUTABLE_SUFFIX
  len += strlen (EXECUTABLE_SUFFIX);
#endif

  temp = xmalloc (len);

  /* Determine the filename to execute (special case for absolute paths).  */

  if (*name == '/')
    {
      if (access (name, X_OK) == 0)
	{
	  strcpy (temp, name);
	  return temp;
	}
    }
  else
    for (pl = pprefix->plist; pl; pl = pl->next)
      {
	strcpy (temp, pl->prefix);
	strcat (temp, name);
	if (! is_in_prefix_list (&our_file_names, temp, 1)
	    /* This is a kludge, but there seems no way around it.  */
	    && strcmp (temp, "./ld") != 0
	    && access (temp, X_OK) == 0)
	  return temp;

#ifdef EXECUTABLE_SUFFIX
	/* Some systems have a suffix for executable files.
	   So try appending that.  */
	strcat (temp, EXECUTABLE_SUFFIX);
	if (! is_in_prefix_list (&our_file_names, temp, 1)
	    && access (temp, X_OK) == 0)
	  return temp;
#endif
      }

  free (temp);
  return 0;
}

/* Add an entry for PREFIX to prefix list PPREFIX.  */

static void
add_prefix (pprefix, prefix)
     struct path_prefix *pprefix;
     char *prefix;
{
  struct prefix_list *pl, **prev;
  int len;

  if (pprefix->plist)
    {
      for (pl = pprefix->plist; pl->next; pl = pl->next)
	;
      prev = &pl->next;
    }
  else
    prev = &pprefix->plist;

  /* Keep track of the longest prefix */

  len = strlen (prefix);
  if (len > pprefix->max_len)
    pprefix->max_len = len;

  pl = (struct prefix_list *) xmalloc (sizeof (struct prefix_list));
  pl->prefix = savestring (prefix, len);

  if (*prev)
    pl->next = *prev;
  else
    pl->next = (struct prefix_list *) 0;
  *prev = pl;
}

/* Take the value of the environment variable ENV, break it into a path, and
   add of the entries to PPREFIX.  */

static void
prefix_from_env (env, pprefix)
     char *env;
     struct path_prefix *pprefix;
{
  char *p = getenv (env);

  if (p)
    prefix_from_string (p, pprefix);
}

static void
prefix_from_string (p, pprefix)
     char *p;
     struct path_prefix *pprefix;
{
  char *startp, *endp;
  char *nstore = (char *) xmalloc (strlen (p) + 3);

  startp = endp = p;
  while (1)
    {
      if (*endp == PATH_SEPARATOR || *endp == 0)
	{
	  strncpy (nstore, startp, endp-startp);
	  if (endp == startp)
	    {
	      strcpy (nstore, "./");
	    }
	  else if (endp[-1] != '/')
	    {
	      nstore[endp-startp] = '/';
	      nstore[endp-startp+1] = 0;
	    }
	  else
	    nstore[endp-startp] = 0;

	  add_prefix (pprefix, nstore);
	  if (*endp == 0)
	    break;
	  endp = startp = endp + 1;
	}
      else
	endp++;
    }
}

/* Main program. */

int
main (argc, argv)
     int argc;
     char *argv[];
{
  char *ld_suffix	= "ld";
  char *full_ld_suffix	= ld_suffix;
  char *real_ld_suffix	= "real-ld";
  char *full_real_ld_suffix = real_ld_suffix;
  char *collect_ld_suffix = "collect-ld";
  char *nm_suffix	= "nm";
  char *full_nm_suffix	= nm_suffix;
  char *gnm_suffix	= "gnm";
  char *full_gnm_suffix	= gnm_suffix;
#ifdef LDD_SUFFIX
  char *ldd_suffix	= LDD_SUFFIX;
  char *full_ldd_suffix	= ldd_suffix;
#endif
  char *strip_suffix	= "strip";
  char *full_strip_suffix = strip_suffix;
  char *gstrip_suffix	= "gstrip";
  char *full_gstrip_suffix = gstrip_suffix;
  char *arg;
  FILE *outf, *exportf;
  char *ld_file_name;
  char *collect_name;
  char *collect_names;
  char *p;
  char **c_argv;
  char **c_ptr;
  char **ld1_argv	= (char **) xcalloc (sizeof (char *), argc+3);
  char **ld1		= ld1_argv;
  char **ld2_argv	= (char **) xcalloc (sizeof (char *), argc+6);
  char **ld2		= ld2_argv;
  char **object_lst	= (char **) xcalloc (sizeof (char *), argc);
  char **object		= object_lst;
  int first_file;
  int num_c_args	= argc+7;

#ifdef DEBUG
  debug = 1;
  vflag = 1;
#endif

  output_file = "a.out";

  obstack_begin (&temporary_obstack, 0);
  obstack_begin (&permanent_obstack, 0);
  temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
  current_demangling_style = gnu_demangling;

  /* We must check that we do not call ourselves in an infinite
     recursion loop. We append the name used for us to the COLLECT_NAMES
     environment variable.

     In practice, collect will rarely invoke itself.  This can happen now
     that we are no longer called gld.  A perfect example is when running
     gcc in a build directory that has been installed.  When looking for 
     ld's, we'll find our installed version and believe that's the real ld.  */

  /* We must also append COLLECT_NAME to COLLECT_NAMES to watch for the
     previous version of collect (the one that used COLLECT_NAME and only
     handled two levels of recursion).  If we don't we may mutually recurse
     forever.  This can happen (I think) when bootstrapping the old version
     and a new one is installed (rare, but we should handle it).
     ??? Hopefully references to COLLECT_NAME can be removed at some point.  */

  collect_name = (char *) getenv ("COLLECT_NAME");
  collect_names = (char *) getenv ("COLLECT_NAMES");

  p = (char *) xmalloc (strlen ("COLLECT_NAMES=")
			+ (collect_name ? strlen (collect_name) + 1 : 0)
			+ (collect_names ? strlen (collect_names) + 1 : 0)
			+ strlen (argv[0]) + 1);
  strcpy (p, "COLLECT_NAMES=");
  if (collect_name != 0)
    sprintf (p + strlen (p), "%s%c", collect_name, PATH_SEPARATOR);
  if (collect_names != 0)
    sprintf (p + strlen (p), "%s%c", collect_names, PATH_SEPARATOR);
  strcat (p, argv[0]);
  putenv (p);

  prefix_from_env ("COLLECT_NAMES", &our_file_names);

  /* Set environment variable COLLECT_NAME to our name so the previous version
     of collect won't find us.  If it does we'll mutually recurse forever.
     This can happen when bootstrapping the new version and an old version is
     installed.
     ??? Hopefully this bit of code can be removed at some point.  */

  p = xmalloc (strlen ("COLLECT_NAME=") + strlen (argv[0]) + 1);
  sprintf (p, "COLLECT_NAME=%s", argv[0]);
  putenv (p);

  p = (char *) getenv ("COLLECT_GCC_OPTIONS");
  if (p)
    while (*p)
      {
	char *q = p;
	while (*q && *q != ' ') q++;
	if (*p == '-' && p[1] == 'm')
	  num_c_args++;

	if (*q) q++;
	p = q;
      }

  c_ptr = c_argv = (char **) xcalloc (sizeof (char *), num_c_args);

  if (argc < 2)
    fatal ("no arguments");

#ifdef SIGQUIT
  if (signal (SIGQUIT, SIG_IGN) != SIG_IGN)
    signal (SIGQUIT, handler);
#endif
  if (signal (SIGINT, SIG_IGN) != SIG_IGN)
    signal (SIGINT, handler);
#ifdef SIGALRM
  if (signal (SIGALRM, SIG_IGN) != SIG_IGN)
    signal (SIGALRM, handler);
#endif
#ifdef SIGHUP
  if (signal (SIGHUP, SIG_IGN) != SIG_IGN)
    signal (SIGHUP, handler);
#endif
  if (signal (SIGSEGV, SIG_IGN) != SIG_IGN)
    signal (SIGSEGV, handler);
#ifdef SIGBUS
  if (signal (SIGBUS, SIG_IGN) != SIG_IGN)
    signal (SIGBUS, handler);
#endif

  /* Extract COMPILER_PATH and PATH into our prefix list.  */
  prefix_from_env ("COMPILER_PATH", &cpath);
  prefix_from_env ("PATH", &path);

#ifdef CROSS_COMPILE
  /* If we look for a program in the compiler directories, we just use
     the short name, since these directories are already system-specific.
     But it we look for a took in the system directories, we need to
     qualify the program name with the target machine.  */

  full_ld_suffix
    = xcalloc (strlen (ld_suffix) + strlen (target_machine) + 2, 1);
  strcpy (full_ld_suffix, target_machine);
  strcat (full_ld_suffix, "-");
  strcat (full_ld_suffix, ld_suffix);

  full_real_ld_suffix
    = xcalloc (strlen (real_ld_suffix) + strlen (target_machine) + 2, 1);
  strcpy (full_real_ld_suffix, target_machine);
  strcat (full_real_ld_suffix, "-");
  strcat (full_real_ld_suffix, real_ld_suffix);

#if 0
  full_gld_suffix
    = xcalloc (strlen (gld_suffix) + strlen (target_machine) + 2, 1);
  strcpy (full_gld_suffix, target_machine);
  strcat (full_gld_suffix, "-");
  strcat (full_gld_suffix, gld_suffix);
#endif

  full_nm_suffix
    = xcalloc (strlen (nm_suffix) + strlen (target_machine) + 2, 1);
  strcpy (full_nm_suffix, target_machine);
  strcat (full_nm_suffix, "-");
  strcat (full_nm_suffix, nm_suffix);

  full_gnm_suffix
    = xcalloc (strlen (gnm_suffix) + strlen (target_machine) + 2, 1);
  strcpy (full_gnm_suffix, target_machine);
  strcat (full_gnm_suffix, "-");
  strcat (full_gnm_suffix, gnm_suffix);

#ifdef LDD_SUFFIX
  full_ldd_suffix
    = xcalloc (strlen (ldd_suffix) + strlen (target_machine) + 2, 1);
  strcpy (full_ldd_suffix, target_machine);
  strcat (full_ldd_suffix, "-");
  strcat (full_ldd_suffix, ldd_suffix);
#endif

  full_strip_suffix
    = xcalloc (strlen (strip_suffix) + strlen (target_machine) + 2, 1);
  strcpy (full_strip_suffix, target_machine);
  strcat (full_strip_suffix, "-");
  strcat (full_strip_suffix, strip_suffix);
  
  full_gstrip_suffix
    = xcalloc (strlen (gstrip_suffix) + strlen (target_machine) + 2, 1);
  strcpy (full_gstrip_suffix, target_machine);
  strcat (full_gstrip_suffix, "-");
  strcat (full_gstrip_suffix, gstrip_suffix);
#endif /* CROSS_COMPILE */

  /* Try to discover a valid linker/nm/strip to use.  */

  /* Maybe we know the right file to use (if not cross).  */
#ifdef REAL_LD_FILE_NAME
  ld_file_name = find_a_file (&path, REAL_LD_FILE_NAME);
  if (ld_file_name == 0)
#endif
  /* Search the (target-specific) compiler dirs for ld'.  */
  ld_file_name = find_a_file (&cpath, real_ld_suffix);
  /* Likewise for `collect-ld'.  */
  if (ld_file_name == 0)
    ld_file_name = find_a_file (&cpath, collect_ld_suffix);
  /* Search the compiler directories for `ld'.  We have protection against
     recursive calls in find_a_file.  */
  if (ld_file_name == 0)
    ld_file_name = find_a_file (&cpath, ld_suffix);
  /* Search the ordinary system bin directories
     for `ld' (if native linking) or `TARGET-ld' (if cross).  */
  if (ld_file_name == 0)
    ld_file_name = find_a_file (&path, full_ld_suffix);

  /* If we've invoked ourselves, try again with LD_FILE_NAME.  */

  if (collect_names != 0)
    {
      if (ld_file_name != 0)
	{
	  argv[0] = ld_file_name;
	  execvp (argv[0], argv);
	}
      fatal ("cannot find `ld'");
    }

#ifdef REAL_NM_FILE_NAME
  nm_file_name = find_a_file (&path, REAL_NM_FILE_NAME);
  if (nm_file_name == 0)
#endif
  nm_file_name = find_a_file (&cpath, gnm_suffix);
  if (nm_file_name == 0)
    nm_file_name = find_a_file (&path, full_gnm_suffix);
  if (nm_file_name == 0)
    nm_file_name = find_a_file (&cpath, nm_suffix);
  if (nm_file_name == 0)
    nm_file_name = find_a_file (&path, full_nm_suffix);

#ifdef LDD_SUFFIX
  ldd_file_name = find_a_file (&cpath, ldd_suffix);
  if (ldd_file_name == 0)
    ldd_file_name = find_a_file (&path, full_ldd_suffix);
#endif

#ifdef REAL_STRIP_FILE_NAME
  strip_file_name = find_a_file (&path, REAL_STRIP_FILE_NAME);
  if (strip_file_name == 0)
#endif
  strip_file_name = find_a_file (&cpath, gstrip_suffix);
  if (strip_file_name == 0)
    strip_file_name = find_a_file (&path, full_gstrip_suffix);
  if (strip_file_name == 0)
    strip_file_name = find_a_file (&cpath, strip_suffix);
  if (strip_file_name == 0)
    strip_file_name = find_a_file (&path, full_strip_suffix);

  /* Determine the full path name of the C compiler to use.  */
  c_file_name = getenv ("COLLECT_GCC");
  if (c_file_name == 0)
    {
#ifdef CROSS_COMPILE
      c_file_name = xcalloc (sizeof ("gcc-") + strlen (target_machine) + 1, 1);
      strcpy (c_file_name, target_machine);
      strcat (c_file_name, "-gcc");
#else
      c_file_name = "gcc";
#endif
    }

  p = find_a_file (&cpath, c_file_name);

  /* Here it should be safe to use the system search path since we should have
     already qualified the name of the compiler when it is needed.  */
  if (p == 0)
    p = find_a_file (&path, c_file_name);

  if (p)
    c_file_name = p;

  *ld1++ = *ld2++ = ld_file_name;

  /* Make temp file names. */
  choose_temp_base ();
  c_file = xcalloc (temp_filename_length + sizeof (".c"), 1);
  o_file = xcalloc (temp_filename_length + sizeof (".o"), 1);
  export_file = xmalloc (temp_filename_length + sizeof (".x"));
  ldout = xmalloc (temp_filename_length + sizeof (".ld"));
  sprintf (ldout, "%s.ld", temp_filename);
  sprintf (c_file, "%s.c", temp_filename);
  sprintf (o_file, "%s.o", temp_filename);
  sprintf (export_file, "%s.x", temp_filename);
  *c_ptr++ = c_file_name;
  *c_ptr++ = "-c";
  *c_ptr++ = "-o";
  *c_ptr++ = o_file;

  /* !!! When GCC calls collect2,
     it does not know whether it is calling collect2 or ld.
     So collect2 cannot meaningfully understand any options
     except those ld understands.
     If you propose to make GCC pass some other option,
     just imagine what will happen if ld is really ld!!!  */

  /* Parse arguments.  Remember output file spec, pass the rest to ld. */
  /* After the first file, put in the c++ rt0.  */

  first_file = 1;
  while ((arg = *++argv) != (char *)0)
    {
      *ld1++ = *ld2++ = arg;

      if (arg[0] == '-')
	{
	  switch (arg[1])
	    {
	    case 'd':
	      if (!strcmp (arg, "-debug"))
		{
		  debug = 1;
		  vflag = 1;
		  ld1--;
		  ld2--;
		}
	      break;

#ifdef COLLECT_EXPORT_LIST
	    case 'b':
	      if ((!strncmp (arg, "-bE:", 4)
		   || !strncmp (arg, "-bexport:", 9))
		  && strcmp (arg, "-bexport:/usr/lib/libg.exp"))
		auto_export = 0;
	      break;
#endif

	    case 'l':
	      if (first_file)
		{
		  /* place o_file BEFORE this argument! */
		  first_file = 0;
		  ld2--;
		  *ld2++ = o_file;
		  *ld2++ = arg;
		}
	      break;

	    case 'o':
	      if (arg[2] == '\0')
		output_file = *ld1++ = *ld2++ = *++argv;
	      else
		output_file = &arg[2];
	      break;

	    case 'r':
	      if (arg[2] == '\0')
		rflag = 1;
	      break;

	    case 's':
	      if (arg[2] == '\0' && do_collecting)
		{
		  /* We must strip after the nm run, otherwise C++ linking
		     won't work.  Thus we strip in the second ld run, or
		     else with strip if there is no second ld run.  */
		  strip_flag = 1;
		  ld1--;
		}
	      break;

	    case 'v':
	      if (arg[2] == '\0')
		vflag = 1;
	      break;
	    }
	}
      else if ((p = rindex (arg, '.')) != (char *)0
	       && (strcmp (p, ".o") == 0 || strcmp (p, ".a") == 0))
	{
	  if (first_file)
	    {
	      first_file = 0;
	      if (p[1] == 'o')
		*ld2++ = o_file;
	      else
		{
		  /* place o_file BEFORE this argument! */
		  ld2--;
		  *ld2++ = o_file;
		  *ld2++ = arg;
		}
	    }
	  if (p[1] == 'o')
	    *object++ = arg;
	}
    }

  /* Get any options that the upper GCC wants to pass to the sub-GCC.  */
  p = (char *) getenv ("COLLECT_GCC_OPTIONS");
  if (p)
    while (*p)
      {
	char *q = p;
	while (*q && *q != ' ') q++;
	if (*p == '-' && (p[1] == 'm' || p[1] == 'f'))
	  *c_ptr++ = savestring (p, q - p);
	if (strncmp (p, "-shared", sizeof ("shared") - 1) == 0)
	  shared_obj = 1;

	if (*q) q++;
	p = q;
      }

#ifdef COLLECT_EXPORT_LIST
  /* The AIX linker will discard static constructors in object files if
     nothing else in the file is referenced, so look at them first.  */
  while (object_lst < object)
    scan_prog_file (*object_lst++, PASS_OBJ);

  {
    char *buf = alloca (strlen (export_file) + 5);
    sprintf (buf, "-bE:%s", export_file);
    *ld1++ = buf;
    *ld2++ = buf;
    exportf = fopen (export_file, "w");
    if (exportf == (FILE *)0)
      fatal_perror ("%s", export_file);
    write_export_file (exportf);
    if (fclose (exportf))
      fatal_perror ("closing %s", export_file);
  }
#endif

  *c_ptr++ = c_file;
  *object = *c_ptr = *ld1 = (char *)0;

  if (vflag)
    {
      fprintf (stderr, "collect2 version %s", version_string);
#ifdef TARGET_VERSION
      TARGET_VERSION;
#endif
      fprintf (stderr, "\n");
    }

  if (debug)
    {
      char *ptr;
      fprintf (stderr, "ld_file_name        = %s\n",
	       (ld_file_name ? ld_file_name : "not found"));
      fprintf (stderr, "c_file_name         = %s\n",
	       (c_file_name ? c_file_name : "not found"));
      fprintf (stderr, "nm_file_name        = %s\n",
	       (nm_file_name ? nm_file_name : "not found"));
#ifdef LDD_SUFFIX
      fprintf (stderr, "ldd_file_name       = %s\n",
	       (ldd_file_name ? ldd_file_name : "not found"));
#endif
      fprintf (stderr, "strip_file_name     = %s\n",
	       (strip_file_name ? strip_file_name : "not found"));
      fprintf (stderr, "c_file              = %s\n",
	       (c_file ? c_file : "not found"));
      fprintf (stderr, "o_file              = %s\n",
	       (o_file ? o_file : "not found"));

      ptr = getenv ("COLLECT_NAMES");
      if (ptr)
	fprintf (stderr, "COLLECT_NAMES       = %s\n", ptr);

      ptr = getenv ("COLLECT_GCC_OPTIONS");
      if (ptr)
	fprintf (stderr, "COLLECT_GCC_OPTIONS = %s\n", ptr);

      ptr = getenv ("COLLECT_GCC");
      if (ptr)
	fprintf (stderr, "COLLECT_GCC         = %s\n", ptr);

      ptr = getenv ("COMPILER_PATH");
      if (ptr)
	fprintf (stderr, "COMPILER_PATH       = %s\n", ptr);

      ptr = getenv ("LIBRARY_PATH");
      if (ptr)
	fprintf (stderr, "LIBRARY_PATH        = %s\n", ptr);

      fprintf (stderr, "\n");
    }

  /* Load the program, searching all libraries.  */

  collect_execute ("ld", ld1_argv, ldout);
  do_wait ("ld");
  dump_file (ldout);
  unlink (ldout);

  /* If -r or they'll be run via some other method, don't build the
     constructor or destructor list, just return now. */
  if (rflag || ! do_collecting)
    return 0;

  /* Examine the namelist with nm and search it for static constructors
     and destructors to call.
     Write the constructor and destructor tables to a .s file and reload. */

  scan_prog_file (output_file, PASS_FIRST);

#ifdef SCAN_LIBRARIES
  scan_libraries (output_file);
#endif

  if (debug)
    {
      fprintf (stderr, "%d constructor(s) found\n", constructors.number);
      fprintf (stderr, "%d destructor(s)  found\n", destructors.number);
    }

  if (constructors.number == 0 && destructors.number == 0
#ifdef LDD_SUFFIX
      /* If we will be running these functions ourselves, we want to emit
	 stubs into the shared library so that we don't have to relink
	 dependent programs when we add static objects.  */
      && ! shared_obj
#endif
      )
    {
      /* Strip now if it was requested on the command line.  */
      if (strip_flag)
	{
	  char **strip_argv = (char **) xcalloc (sizeof (char *), 3);
	  strip_argv[0] = strip_file_name;
	  strip_argv[1] = output_file;
	  strip_argv[2] = (char *) 0;
	  fork_execute ("strip", strip_argv);
	}

#ifdef COLLECT_EXPORT_LIST
      maybe_unlink (export_file);
#endif
      return 0;
    }

  maybe_unlink(output_file);
  outf = fopen (c_file, "w");
  if (outf == (FILE *)0)
    fatal_perror ("%s", c_file);

  write_c_file (outf, c_file);

  if (fclose (outf))
    fatal_perror ("closing %s", c_file);

  /* Tell the linker that we have initializer and finalizer functions.  */
#ifdef LD_INIT_SWITCH
  *ld2++ = LD_INIT_SWITCH;
  *ld2++ = initname;
  *ld2++ = LD_FINI_SWITCH;
  *ld2++ = fininame;
#endif
  *ld2 = (char*)0;

#ifdef COLLECT_EXPORT_LIST
  if (shared_obj)
    {
      add_to_list (&exports, initname);
      add_to_list (&exports, fininame);
      add_to_list (&exports, "_GLOBAL__DI");
      add_to_list (&exports, "_GLOBAL__DD");
      exportf = fopen (export_file, "w");
      if (exportf == (FILE *)0)
	fatal_perror ("%s", export_file);
      write_export_file (exportf);
      if (fclose (exportf))
	fatal_perror ("closing %s", export_file);
    }
#endif

  if (debug)
    {
      fprintf (stderr, "\n========== output_file = %s, c_file = %s\n",
	       output_file, c_file);
      write_c_file (stderr, "stderr");
      fprintf (stderr, "========== end of c_file\n\n");
#ifdef COLLECT_EXPORT_LIST
      fprintf (stderr, "\n========== export_file = %s\n", export_file);
      write_export_file (stderr);
      fprintf (stderr, "========== end of export_file\n\n");
#endif
    }

  /* Assemble the constructor and destructor tables.
     Link the tables in with the rest of the program. */

  fork_execute ("gcc",  c_argv);
  fork_execute ("ld", ld2_argv);

  /* Let scan_prog_file do any final mods (OSF/rose needs this for
     constructors/destructors in shared libraries.  */
  scan_prog_file (output_file, PASS_SECOND);

  maybe_unlink (c_file);
  maybe_unlink (o_file);
  maybe_unlink (export_file);
  return 0;
}


/* Wait for a process to finish, and exit if a non-zero status is found. */

int
collect_wait (prog)
     char *prog;
{
  int status;

  wait (&status);
  if (status)
    {
      if (WIFSIGNALED (status))
	{
	  int sig = WTERMSIG (status);
#ifdef NO_SYS_SIGLIST
	  error ("%s terminated with signal %d %s",
		 prog,
		 sig,
		 (status & 0200) ? ", core dumped" : "");
#else
	  error ("%s terminated with signal %d [%s]%s",
		 prog,
		 sig,
		 sys_siglist[sig],
		 (status & 0200) ? ", core dumped" : "");
#endif

	  collect_exit (127);
	}

      if (WIFEXITED (status))
	return WEXITSTATUS (status);
    }
  return 0;
}

static void
do_wait (prog)
     char *prog;
{
  int ret = collect_wait (prog);
  if (ret != 0)
    {
      error ("%s returned %d exit status", prog, ret);
      collect_exit (ret);
    }
}


/* Fork and execute a program, and wait for the reply.  */

void
collect_execute (prog, argv, redir)
     char *prog;
     char **argv;
     char *redir;
{
  int pid;

  if (vflag || debug)
    {
      char **p_argv;
      char *str;

      if (argv[0])
	fprintf (stderr, "%s", argv[0]);
      else
	fprintf (stderr, "[cannot find %s]", prog);

      for (p_argv = &argv[1]; (str = *p_argv) != (char *)0; p_argv++)
	fprintf (stderr, " %s", str);

      fprintf (stderr, "\n");
    }

  fflush (stdout);
  fflush (stderr);

  /* If we can't find a program we need, complain error.  Do this here
     since we might not end up needing something that we couldn't find.  */

  if (argv[0] == 0)
    fatal ("cannot find `%s'", prog);

  pid = vfork ();
  if (pid == -1)
    {
#ifdef vfork
      fatal_perror ("fork");
#else
      fatal_perror ("vfork");
#endif
    }

  if (pid == 0)			/* child context */
    {
      if (redir)
	{
	  unlink (redir);
	  if (freopen (redir, "a", stdout) == NULL)
	    fatal_perror ("redirecting stdout");
	  if (freopen (redir, "a", stderr) == NULL)
	    fatal_perror ("redirecting stderr");
	}

      execvp (argv[0], argv);
      fatal_perror ("executing %s", prog);
    }
}

static void
fork_execute (prog, argv)
     char *prog;
     char **argv;
{
  collect_execute (prog, argv, NULL);
  do_wait (prog);
}

/* Unlink a file unless we are debugging.  */

static void
maybe_unlink (file)
     char *file;
{
  if (!debug)
    unlink (file);
  else
    fprintf (stderr, "[Leaving %s]\n", file);
}


/* Add a name to a linked list.  */

static void
add_to_list (head_ptr, name)
     struct head *head_ptr;
     char *name;
{
  struct id *newid
    = (struct id *) xcalloc (sizeof (struct id) + strlen (name), 1);
  struct id *p;
  static long sequence_number = 0;
  strcpy (newid->name, name);

  if (head_ptr->first)
    head_ptr->last->next = newid;
  else
    head_ptr->first = newid;

  /* Check for duplicate symbols.  */
  for (p = head_ptr->first;
       strcmp (name, p->name) != 0;
       p = p->next)
    ;
  if (p != newid)
    {
      head_ptr->last->next = 0;
      free (newid);
      return;
    }

  newid->sequence = ++sequence_number;
  head_ptr->last = newid;
  head_ptr->number++;
}

/* Write: `prefix', the names on list LIST, `suffix'.  */

static void
write_list (stream, prefix, list)
     FILE *stream;
     char *prefix;
     struct id *list;
{
  while (list)
    {
      fprintf (stream, "%sx%d,\n", prefix, list->sequence);
      list = list->next;
    }
}

static void
write_list_with_asm (stream, prefix, list)
     FILE *stream;
     char *prefix;
     struct id *list;
{
  while (list)
    {
      fprintf (stream, "%sx%d __asm__ (\"%s\");\n",
	       prefix, list->sequence, list->name);
      list = list->next;
    }
}

/* Write out the constructor and destructor tables statically (for a shared
   object), along with the functions to execute them.  */

static void
write_c_file_stat (stream, name)
     FILE *stream;
     char *name;
{
  char *prefix, *p, *q;

  /* Figure out name of output_file, stripping off .so version.  */
  p = rindex (output_file, '/');
  if (p == 0)
    p = (char *) output_file;
  else
    p++;
  q = p;
  while (q)
    {
      q = index (q,'.');
      if (q == 0)
	{
	  q = p + strlen (p);
	  break;
	}
      else
	{
	  if (strncmp (q, ".so", 3) == 0)
	    {
	      q += 3;
	      break;
	    }
	  else
	    q++;
	}
    }
  /* q points to null at end of the string (or . of the .so version) */
  prefix = xmalloc (q - p + 1);
  strncpy (prefix, p, q - p);
  prefix[q - p] = 0;
  for (q = prefix; *q; q++)
    if (!isalnum (*q))
      *q = '_';
  if (debug)
    fprintf (stderr, "\nwrite_c_file - output name is %s, prefix is %s\n",
	     output_file, prefix);

#define INIT_NAME_FORMAT "_GLOBAL__FI_%s"
  initname = xmalloc (strlen (prefix) + sizeof (INIT_NAME_FORMAT) - 2);
  sprintf (initname, INIT_NAME_FORMAT, prefix);

#define FINI_NAME_FORMAT "_GLOBAL__FD_%s"
  fininame = xmalloc (strlen (prefix) + sizeof (FINI_NAME_FORMAT) - 2);
  sprintf (fininame, FINI_NAME_FORMAT, prefix);

  free (prefix);

  /* Write the tables as C code  */

  fprintf (stream, "static int count;\n");
  fprintf (stream, "typedef void entry_pt();\n");
  write_list_with_asm (stream, "extern entry_pt ", constructors.first);
  fprintf (stream, "void %s() {\n", initname);
  if (constructors.number > 0)
    {
      fprintf (stream, "\tstatic entry_pt *ctors[] = {\n");
      write_list (stream, "\t\t", constructors.first);
      fprintf (stream, "\t};\n");
      fprintf (stream, "\tentry_pt **p;\n");
      fprintf (stream, "\tif (count++ != 0) return;\n");
      fprintf (stream, "\tp = ctors + %d;\n", constructors.number);
      fprintf (stream, "\twhile (p > ctors) (*--p)();\n");
    }
  else
    fprintf (stream, "\t++count;\n");
  fprintf (stream, "}\n");
  write_list_with_asm (stream, "extern entry_pt ", destructors.first);
  fprintf (stream, "void %s() {\n", fininame);
  if (destructors.number > 0)
    {
      fprintf (stream, "\tstatic entry_pt *dtors[] = {\n");
      write_list (stream, "\t\t", destructors.first);
      fprintf (stream, "\t};\n");
      fprintf (stream, "\tentry_pt **p;\n");
      fprintf (stream, "\tif (--count != 0) return;\n");
      fprintf (stream, "\tp = dtors;\n");
      fprintf (stream, "\twhile (p < dtors + %d) (*p++)();\n",
	       destructors.number);
    }
  fprintf (stream, "}\n");

  if (shared_obj)
    {
      fprintf (stream, "void _GLOBAL__DI() {\n\t%s();\n}\n", initname);
      fprintf (stream, "void _GLOBAL__DD() {\n\t%s();\n}\n", fininame);
    }
}

/* Write the constructor/destructor tables. */

static void
write_c_file_glob (stream, name)
     FILE *stream;
     char *name;
{
  /* Write the tables as C code  */

  fprintf (stream, "typedef void entry_pt();\n\n");
    
  write_list_with_asm (stream, "extern entry_pt ", constructors.first);
    
  fprintf (stream, "\nentry_pt * __CTOR_LIST__[] = {\n");
  fprintf (stream, "\t(entry_pt *) %d,\n", constructors.number);
  write_list (stream, "\t", constructors.first);
  fprintf (stream, "\t0\n};\n\n");

  write_list_with_asm (stream, "extern entry_pt ", destructors.first);

  fprintf (stream, "\nentry_pt * __DTOR_LIST__[] = {\n");
  fprintf (stream, "\t(entry_pt *) %d,\n", destructors.number);
  write_list (stream, "\t", destructors.first);
  fprintf (stream, "\t0\n};\n\n");

  fprintf (stream, "extern entry_pt %s;\n", NAME__MAIN);
  fprintf (stream, "entry_pt *__main_reference = %s;\n\n", NAME__MAIN);
}

static void
write_c_file (stream, name)
     FILE *stream;
     char *name;
{
#ifndef LD_INIT_SWITCH
  if (! shared_obj)
    write_c_file_glob (stream, name);
  else
#endif
    write_c_file_stat (stream, name);
}

static void
write_export_file (stream)
     FILE *stream;
{
  struct id *list = exports.first;
  for (; list; list = list->next)
    fprintf (stream, "%s\n", list->name);
}

#ifdef OBJECT_FORMAT_NONE

/* Generic version to scan the name list of the loaded program for
   the symbols g++ uses for static constructors and destructors.

   The constructor table begins at __CTOR_LIST__ and contains a count
   of the number of pointers (or -1 if the constructors are built in a
   separate section by the linker), followed by the pointers to the
   constructor functions, terminated with a null pointer.  The
   destructor table has the same format, and begins at __DTOR_LIST__.  */

static void
scan_prog_file (prog_name, which_pass)
     char *prog_name;
     enum pass which_pass;
{
  void (*int_handler) ();
  void (*quit_handler) ();
  char *nm_argv[4];
  int pid;
  int argc = 0;
  int pipe_fd[2];
  char *p, buf[1024];
  FILE *inf;

  if (which_pass == PASS_SECOND)
    return;

  /* If we don't have an `nm', complain.  */
  if (nm_file_name == 0)
    fatal ("cannot find `nm'");

  nm_argv[argc++] = nm_file_name;
  if (NM_FLAGS[0] != '\0')
    nm_argv[argc++] = NM_FLAGS;

  nm_argv[argc++] = prog_name;
  nm_argv[argc++] = (char *)0;

  if (pipe (pipe_fd) < 0)
    fatal_perror ("pipe");

  inf = fdopen (pipe_fd[0], "r");
  if (inf == (FILE *)0)
    fatal_perror ("fdopen");

  /* Trace if needed.  */
  if (vflag)
    {
      char **p_argv;
      char *str;

      for (p_argv = &nm_argv[0]; (str = *p_argv) != (char *)0; p_argv++)
	fprintf (stderr, " %s", str);

      fprintf (stderr, "\n");
    }

  fflush (stdout);
  fflush (stderr);

  /* Spawn child nm on pipe */
  pid = vfork ();
  if (pid == -1)
    {
#ifdef vfork
      fatal_perror ("fork");
#else
      fatal_perror ("vfork");
#endif
    }

  if (pid == 0)			/* child context */
    {
      /* setup stdout */
      if (dup2 (pipe_fd[1], 1) < 0)
	fatal_perror ("dup2 (%d, 1)", pipe_fd[1]);

      if (close (pipe_fd[0]) < 0)
	fatal_perror ("close (%d)", pipe_fd[0]);

      if (close (pipe_fd[1]) < 0)
	fatal_perror ("close (%d)", pipe_fd[1]);

      execv (nm_file_name, nm_argv);
      fatal_perror ("executing %s", nm_file_name);
    }

  /* Parent context from here on.  */
  int_handler  = (void (*) ())signal (SIGINT,  SIG_IGN);
#ifdef SIGQUIT
  quit_handler = (void (*) ())signal (SIGQUIT, SIG_IGN);
#endif

  if (close (pipe_fd[1]) < 0)
    fatal_perror ("close (%d)", pipe_fd[1]);

  if (debug)
    fprintf (stderr, "\nnm output with constructors/destructors.\n");

  /* Read each line of nm output.  */
  while (fgets (buf, sizeof buf, inf) != (char *)0)
    {
      int ch, ch2;
      char *name, *end;

      /* If it contains a constructor or destructor name, add the name
	 to the appropriate list. */

      for (p = buf; (ch = *p) != '\0' && ch != '\n' && ch != '_'; p++)
	if (ch == ' ' && p[1] == 'U' && p[2] == ' ')
	  break;

      if (ch != '_')
	continue;
  
      name = p;
      /* Find the end of the symbol name.
	 Don't include `|', because Encore nm can tack that on the end.  */
      for (end = p; (ch2 = *end) != '\0' && !isspace (ch2) && ch2 != '|';
	   end++)
	continue;


      *end = '\0';
      switch (is_ctor_dtor (name))
	{
	case 1:
	  if (which_pass != PASS_LIB)
	    add_to_list (&constructors, name);
	  break;

	case 2:
	  if (which_pass != PASS_LIB)
	    add_to_list (&destructors, name);
	  break;

	case 3:
	  if (which_pass != PASS_LIB)
	    fatal ("init function found in object %s", prog_name);
#ifndef LD_INIT_SWITCH
	  add_to_list (&constructors, name);
#endif
	  break;

	case 4:
	  if (which_pass != PASS_LIB)
	    fatal ("fini function found in object %s", prog_name);
#ifndef LD_FINI_SWITCH
	  add_to_list (&destructors, name);
#endif
	  break;

	default:		/* not a constructor or destructor */
	  continue;
	}

      if (debug)
	fprintf (stderr, "\t%s\n", buf);
    }

  if (debug)
    fprintf (stderr, "\n");

  if (fclose (inf) != 0)
    fatal_perror ("fclose of pipe");

  do_wait (nm_file_name);

  signal (SIGINT,  int_handler);
#ifdef SIGQUIT
  signal (SIGQUIT, quit_handler);
#endif
}

#if SUNOS4_SHARED_LIBRARIES

/* Routines to scan the SunOS 4 _DYNAMIC structure to find shared libraries
   that the output file depends upon and their initialization/finalization
   routines, if any.  */

#include <a.out.h>
#include <fcntl.h>
#include <link.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <sys/unistd.h>
#include <sys/dir.h>

/* pointers to the object file */
unsigned object;    	/* address of memory mapped file */
unsigned objsize;    	/* size of memory mapped to file */
char * code;		/* pointer to code segment */
char * data;		/* pointer to data segment */
struct nlist *symtab;	/* pointer to symbol table */
struct link_dynamic *ld;
struct link_dynamic_2 *ld_2;
struct head libraries;

/* Map the file indicated by NAME into memory and store its address.  */

static void
mapfile (name)
     char *name;
{
  int fp;
  struct stat s;
  if ((fp = open (name, O_RDONLY)) == -1)
    fatal ("unable to open file '%s'", name);
  if (fstat (fp, &s) == -1)
    fatal ("unable to stat file '%s'", name);

  objsize = s.st_size;
  object = (unsigned) mmap (0, objsize, PROT_READ|PROT_WRITE, MAP_PRIVATE,
			    fp, 0);
  if (object == -1)
    fatal ("unable to mmap file '%s'", name);

  close (fp);
}

/* Helpers for locatelib.  */

static char *libname;

static int
libselect (d)
     struct direct *d;
{
  return (strncmp (libname, d->d_name, strlen (libname)) == 0);
}

/* If one file has an additional numeric extension past LIBNAME, then put
   that one first in the sort.  If both files have additional numeric
   extensions, then put the one with the higher number first in the sort.

   We must verify that the extension is numeric, because Sun saves the
   original versions of patched libraries with a .FCS extension.  Files with
   invalid extensions must go last in the sort, so that they won't be used.  */

static int
libcompare (d1, d2)
     struct direct **d1, **d2;
{
  int i1, i2 = strlen (libname);
  char *e1 = (*d1)->d_name + i2;
  char *e2 = (*d2)->d_name + i2;

  while (*e1 && *e2 && *e1 == '.' && *e2 == '.'
	 && e1[1] && isdigit (e1[1]) && e2[1] && isdigit (e2[1]))
    {
      ++e1;
      ++e2;
      i1 = strtol (e1, &e1, 10);
      i2 = strtol (e2, &e2, 10);
      if (i1 != i2)
	return i1 - i2;
    }

  if (*e1)
    {
      /* It has a valid numeric extension, prefer this one.  */
      if (*e1 == '.' && e1[1] && isdigit (e1[1]))
	return 1;
      /* It has a invalid numeric extension, must prefer the other one.  */
      else
	return -1;
    }
  else if (*e2)
    {
      /* It has a valid numeric extension, prefer this one.  */
      if (*e2 == '.' && e2[1] && isdigit (e2[1]))
	return -1;
      /* It has a invalid numeric extension, must prefer the other one.  */
      else
	return 1;
    }
  else
    return 0;
}

/* Given the name NAME of a dynamic dependency, find its pathname and add
   it to the list of libraries.  */

static void
locatelib (name)
     char *name;
{
  static char **l;
  static int cnt;
  char buf[MAXPATHLEN];
  char *p, *q;
  char **pp;

  if (l == 0)
    {
      char *ld_rules;
      char *ldr = 0;
      /* counting elements in array, need 1 extra for null */
      cnt = 1;  
      ld_rules = (char *) (ld_2->ld_rules + code);
      if (ld_rules)
	{
	  cnt++;
	  for (; *ld_rules != 0; ld_rules++)
	    if (*ld_rules == ':')
	      cnt++;
	  ld_rules = (char *) (ld_2->ld_rules + code);
	  ldr = (char *) malloc (strlen (ld_rules) + 1);
	  strcpy (ldr, ld_rules);
	}
      p = getenv ("LD_LIBRARY_PATH");
      q = 0;
      if (p)
	{
	  cnt++;
	  for (q = p ; *q != 0; q++)
	    if (*q == ':')
	      cnt++;
	  q = (char *) malloc (strlen (p) + 1);
	  strcpy (q, p);
	}
      l = (char **) malloc ((cnt + 3) * sizeof (char *));
      pp = l;
      if (ldr)
	{
	  *pp++ = ldr;
	  for (; *ldr != 0; ldr++) 
	    if (*ldr == ':')
	      {
		*ldr++ = 0;
		*pp++ = ldr;
	      }
	}
      if (q)
	{
	  *pp++ = q;
	  for (; *q != 0; q++) 
	    if (*q == ':')
	      {
		*q++ = 0;
		*pp++ = q;
	      }
	}
      /* built in directories are /lib, /usr/lib, and /usr/local/lib */
      *pp++ = "/lib";
      *pp++ = "/usr/lib";
      *pp++ = "/usr/local/lib";
      *pp = 0;
    }
  libname = name;
  for (pp = l; *pp != 0 ; pp++)
    {
      struct direct **namelist;
      int entries;
      if ((entries = scandir (*pp, &namelist, libselect, libcompare)) > 0)
	{
	  sprintf (buf, "%s/%s", *pp, namelist[entries - 1]->d_name);
	  add_to_list (&libraries, buf);
	  if (debug)
	    fprintf (stderr, "%s\n", buf);
	  break;
	}
    }
  if (*pp == 0)
    {
      if (debug)
	fprintf (stderr, "not found\n");
      else
	fatal ("dynamic dependency %s not found", name);
    }
}

/* Scan the _DYNAMIC structure of the output file to find shared libraries
   that it depends upon and any constructors or destructors they contain.  */

static void 
scan_libraries (prog_name)
     char *prog_name;
{
  struct exec *header;
  char *base;
  struct link_object *lo;
  char buff[MAXPATHLEN];
  struct id *list;

  mapfile (prog_name);
  header = (struct exec *)object;
  if (N_BADMAG (*header))
    fatal ("bad magic number in file '%s'", prog_name);
  if (header->a_dynamic == 0)
    return;

  code = (char *) (N_TXTOFF (*header) + (long) header);
  data = (char *) (N_DATOFF (*header) + (long) header);
  symtab = (struct nlist *) (N_SYMOFF (*header) + (long) header);

  if (header->a_magic == ZMAGIC && header->a_entry == 0x20)
    {
      /* shared object */
      ld = (struct link_dynamic *) (symtab->n_value + code);
      base = code;
    }
  else
    {
      /* executable */
      ld = (struct link_dynamic *) data;
      base = code-PAGSIZ;
    }

  if (debug)
    fprintf (stderr, "dynamic dependencies.\n");

  ld_2 = (struct link_dynamic_2 *) ((long) ld->ld_un.ld_2 + (long)base);
  for (lo = (struct link_object *) ld_2->ld_need; lo;
       lo = (struct link_object *) lo->lo_next)
    {
      char *name;
      lo = (struct link_object *) ((long) lo + code);
      name = (char *) (code + lo->lo_name);
      if (lo->lo_library)
	{
	  if (debug)
	    fprintf (stderr, "\t-l%s.%d => ", name, lo->lo_major);
	  sprintf (buff, "lib%s.so.%d.%d", name, lo->lo_major, lo->lo_minor);
	  locatelib (buff);
	}
      else
	{
	  if (debug)
	    fprintf (stderr, "\t%s\n", name);
	  add_to_list (&libraries, name);
	}
    }

  if (debug)
    fprintf (stderr, "\n");

  /* now iterate through the library list adding their symbols to
     the list.  */
  for (list = libraries.first; list; list = list->next)
    scan_prog_file (list->name, PASS_LIB);
}

#else  /* SUNOS4_SHARED_LIBRARIES */
#ifdef LDD_SUFFIX

/* Use the List Dynamic Dependencies program to find shared libraries that
   the output file depends upon and their initialization/finalization
   routines, if any.  */

static void 
scan_libraries (prog_name)
     char *prog_name;
{
  static struct head libraries;		/* list of shared libraries found */
  struct id *list;
  void (*int_handler) ();
  void (*quit_handler) ();
  char *ldd_argv[4];
  int pid;
  int argc = 0;
  int pipe_fd[2];
  char buf[1024];
  FILE *inf;

  /* If we don't have an `ldd', complain.  */
  if (ldd_file_name == 0)
    {
      error ("cannot find `ldd'");
      return;
    }

  ldd_argv[argc++] = ldd_file_name;
  ldd_argv[argc++] = prog_name;
  ldd_argv[argc++] = (char *) 0;

  if (pipe (pipe_fd) < 0)
    fatal_perror ("pipe");

  inf = fdopen (pipe_fd[0], "r");
  if (inf == (FILE *) 0)
    fatal_perror ("fdopen");

  /* Trace if needed.  */
  if (vflag)
    {
      char **p_argv;
      char *str;

      for (p_argv = &ldd_argv[0]; (str = *p_argv) != (char *) 0; p_argv++)
	fprintf (stderr, " %s", str);

      fprintf (stderr, "\n");
    }

  fflush (stdout);
  fflush (stderr);

  /* Spawn child ldd on pipe */
  pid = vfork ();
  if (pid == -1)
    {
#ifdef vfork
      fatal_perror ("fork");
#else
      fatal_perror ("vfork");
#endif
    }

  if (pid == 0)			/* child context */
    {
      /* setup stdout */
      if (dup2 (pipe_fd[1], 1) < 0)
	fatal_perror ("dup2 (%d, 1)", pipe_fd[1]);

      if (close (pipe_fd[0]) < 0)
	fatal_perror ("close (%d)", pipe_fd[0]);

      if (close (pipe_fd[1]) < 0)
	fatal_perror ("close (%d)", pipe_fd[1]);

      execv (ldd_file_name, ldd_argv);
      fatal_perror ("executing %s", ldd_file_name);
    }

  /* Parent context from here on.  */
  int_handler  = (void (*) ()) signal (SIGINT,  SIG_IGN);
#ifdef SIGQUIT
  quit_handler = (void (*) ()) signal (SIGQUIT, SIG_IGN);
#endif

  if (close (pipe_fd[1]) < 0)
    fatal_perror ("close (%d)", pipe_fd[1]);

  if (debug)
    fprintf (stderr, "\nldd output with constructors/destructors.\n");

  /* Read each line of ldd output.  */
  while (fgets (buf, sizeof buf, inf) != (char *) 0)
    {
      int ch, ch2;
      char *name, *end, *p = buf;

      /* Extract names of libraries and add to list. */
      PARSE_LDD_OUTPUT (p);
      if (p == 0)
	continue;

      name = p;
      if (strncmp (name, "not found", sizeof ("not found") - 1) == 0)
	fatal ("dynamic dependency %s not found", buf);

      /* Find the end of the symbol name. */
      for (end = p; 
	   (ch2 = *end) != '\0' && ch2 != '\n' && !isspace (ch2) && ch2 != '|';
	   end++)
	continue;
      *end = '\0';

      if (access (name, R_OK) == 0)
        add_to_list (&libraries, name);
      else
	fatal ("unable to open dynamic dependency '%s'", buf);

      if (debug)
	fprintf (stderr, "\t%s\n", buf);
    }
  if (debug)
    fprintf (stderr, "\n");

  if (fclose (inf) != 0)
    fatal_perror ("fclose of pipe");

  do_wait (ldd_file_name);

  signal (SIGINT,  int_handler);
#ifdef SIGQUIT
  signal (SIGQUIT, quit_handler);
#endif

  /* now iterate through the library list adding their symbols to
     the list.  */
  for (list = libraries.first; list; list = list->next)
    scan_prog_file (list->name, PASS_LIB);
}

#endif /* LDD_SUFFIX */
#endif /* SUNOS4_SHARED_LIBRARIES */

#endif /* OBJECT_FORMAT_NONE */


/*
 * COFF specific stuff.
 */

#ifdef OBJECT_FORMAT_COFF

#if defined(EXTENDED_COFF)
#   define GCC_SYMBOLS(X)	(SYMHEADER(X).isymMax + SYMHEADER(X).iextMax)
#   define GCC_SYMENT		SYMR
#   define GCC_OK_SYMBOL(X)	((X).st == stProc && (X).sc == scText)
#   define GCC_SYMINC(X)	(1)
#   define GCC_SYMZERO(X)	(SYMHEADER(X).isymMax)
#   define GCC_CHECK_HDR(X)	(PSYMTAB(X) != 0)
#else
#   define GCC_SYMBOLS(X)	(HEADER(ldptr).f_nsyms)
#   define GCC_SYMENT		SYMENT
#   define GCC_OK_SYMBOL(X) \
     (((X).n_sclass == C_EXT) && \
        (((X).n_type & N_TMASK) == (DT_NON << N_BTSHFT) || \
         ((X).n_type & N_TMASK) == (DT_FCN << N_BTSHFT)))
#   define GCC_SYMINC(X)	((X).n_numaux+1)
#   define GCC_SYMZERO(X)	0
#   define GCC_CHECK_HDR(X)	(1)
#endif

extern char *ldgetname ();

/* COFF version to scan the name list of the loaded program for
   the symbols g++ uses for static constructors and destructors.

   The constructor table begins at __CTOR_LIST__ and contains a count
   of the number of pointers (or -1 if the constructors are built in a
   separate section by the linker), followed by the pointers to the
   constructor functions, terminated with a null pointer.  The
   destructor table has the same format, and begins at __DTOR_LIST__.  */

static void
scan_prog_file (prog_name, which_pass)
     char *prog_name;
     enum pass which_pass;
{
  LDFILE *ldptr = NULL;
  int sym_index, sym_count;

  if (which_pass != PASS_FIRST && which_pass != PASS_OBJ)
    return;

  if ((ldptr = ldopen (prog_name, ldptr)) == NULL)
    fatal ("%s: can't open as COFF file", prog_name);
      
  if (!MY_ISCOFF (HEADER (ldptr).f_magic))
    fatal ("%s: not a COFF file", prog_name);

  if (GCC_CHECK_HDR (ldptr))
    {
      sym_count = GCC_SYMBOLS (ldptr);
      sym_index = GCC_SYMZERO (ldptr);
      while (sym_index < sym_count)
	{
	  GCC_SYMENT symbol;

	  if (ldtbread (ldptr, sym_index, &symbol) <= 0)
	    break;
	  sym_index += GCC_SYMINC (symbol);

	  if (GCC_OK_SYMBOL (symbol))
	    {
	      char *name;

	      if ((name = ldgetname (ldptr, &symbol)) == NULL)
		continue;		/* should never happen */

#ifdef XCOFF_DEBUGGING_INFO
	      /* All AIX function names have a duplicate entry beginning
		 with a dot. */
	      if (*name == '.')
		++name;
#endif

	      switch (is_ctor_dtor (name))
		{
		case 1:
		  add_to_list (&constructors, name);
		  if (which_pass == PASS_OBJ)
		    add_to_list (&exports, name);
		  break;

		case 2:
		  add_to_list (&destructors, name);
		  if (which_pass == PASS_OBJ)
		    add_to_list (&exports, name);
		  break;

		default:		/* not a constructor or destructor */
		  if (which_pass == PASS_OBJ && auto_export)
		    add_to_list (&exports, name);
		  continue;
		}

#if !defined(EXTENDED_COFF)
	      if (debug)
		fprintf (stderr, "\tsec=%d class=%d type=%s%o %s\n",
			 symbol.n_scnum, symbol.n_sclass,
			 (symbol.n_type ? "0" : ""), symbol.n_type,
			 name);
#else
	      if (debug)
		fprintf (stderr, "\tiss = %5d, value = %5d, index = %5d, name = %s\n",
			 symbol.iss, symbol.value, symbol.index, name);
#endif
	    }
	}
    }

  (void) ldclose(ldptr);
}

#ifdef XCOFF_SCAN_LIBS
/* Scan imported AIX libraries for GCC static ctors and dtors.
   FIXME: it is possible to link an executable without the actual import
	  library by using an "import file" - a text file listing symbols
	  exported by a library.  To support this, we would have to scan
	  import files as well as actual shared binaries to find GCC ctors.
   TODO: use memory mapping instead of 'ld' routines, files are already
	 memory mapped, but we could eliminate the extra in-memory copies.
	 Is it worth the effort?  */

static void
scan_libraries (prog_name)
     char *prog_name;
{
  LDFILE *ldptr;
  SCNHDR ldsh;
  static struct path_prefix libpath; /* we should only do this once */

  if ((ldptr = ldopen (prog_name, ldptr)) == NULL)
    fatal ("%s: can't open as COFF file", prog_name);
      
  if (!MY_ISCOFF (HEADER (ldptr).f_magic))
    fatal ("%s: not a COFF file", prog_name);

  /* find and read loader section */
  if (ldnshread (ldptr, _LOADER, &ldsh))
    {
      LDHDR ldh;
      char *impbuf;
      int idx;
      FSEEK (ldptr, ldsh.s_scnptr, BEGINNING);
      FREAD (&ldh, sizeof ldh, 1, ldptr);
      /* read import library list */
      impbuf = alloca (ldh.l_istlen);
      FSEEK (ldptr, ldh.l_impoff + ldsh.s_scnptr, BEGINNING);
      FREAD (impbuf, ldh.l_istlen, 1, ldptr);
      idx = strlen (impbuf) + 1;
      idx += strlen (impbuf+idx) + 1;
      if (debug)
	fprintf (stderr, "LIBPATH=%s\n", impbuf);
      prefix_from_string (impbuf, &libpath);
      while (idx < ldh.l_istlen)
	{
	  char *implib = impbuf + idx;
	  char *impmem = implib + strlen (implib) + 1;
	  char *soname = 0;
	  LDFILE *libptr = NULL;
	  struct prefix_list *pl;
	  ARCHDR ah;
	  idx += strlen (implib) + 1;
	  if (!implib[0])
	    continue;
	  idx += strlen (impmem) + 1;
	  if (*implib == '/')
	    {
	      if (access (soname, R_OK) == 0)
		soname = implib;
	    }
	  else
	    {
	      char *temp = alloca (libpath.max_len + strlen (implib) + 1);
	      for (pl = libpath.plist; pl; pl = pl->next)
		{
		  strcpy (temp, pl->prefix);
		  strcat (temp, implib);
		  if (access (temp, R_OK) == 0)
		    {
		      soname = temp;
		      break;
		    }
		}
	    }
	  if (!soname)
	    {
	      fatal ("%s: library not found", implib);
	      continue;
	    }
	  if (debug)
	    {
	      if (impmem[0])
		fprintf (stderr, "%s (%s)\n", soname, impmem);
	      else
		fprintf (stderr, "%s\n", soname);
	    }
	  ah.ar_name[0] = 0;
	  do
	    {
	      /* scan imported shared objects for GCC GLOBAL ctors */
	      short type;
	      if ((libptr = ldopen (soname, libptr)) == NULL)
		fatal ("%s: can't open import library", soname);
	      if (TYPE (libptr) == ARTYPE)
		{
		  LDFILE *memptr;
		  if (!impmem[0])
		    fatal ("%s: no archive member specified", soname);
		  ldahread (libptr, &ah);
		  if (strcmp (ah.ar_name, impmem))
		    continue;
		}
	      type = HEADER (libptr).f_magic;
	      if (HEADER (libptr).f_flags & F_SHROBJ)
		{
		  SCNHDR soldsh;
		  LDHDR soldh;
		  long symcnt, i;
		  char *ldstrings;
		  LDSYM *lsyms;
		  if (!ldnshread (libptr, _LOADER, &soldsh))
		    fatal ("%s: not an import library", soname);
		  FSEEK (libptr, soldsh.s_scnptr, BEGINNING);
		  if (FREAD (&soldh, sizeof soldh, 1, libptr) != 1)
		    fatal ("%s: can't read loader section", soname);
		  /*fprintf (stderr, "\tscanning %s\n", soname);*/
		  symcnt = soldh.l_nsyms;
		  lsyms = (LDSYM*) alloca (symcnt * sizeof *lsyms);
		  symcnt = FREAD (lsyms, sizeof *lsyms, symcnt, libptr);
		  ldstrings = alloca (soldh.l_stlen);
		  FSEEK (libptr, soldsh.s_scnptr+soldh.l_stoff, BEGINNING);
		  FREAD (ldstrings, soldh.l_stlen, 1, libptr);
		  for (i = 0; i < symcnt; ++i)
		    {
		      LDSYM *l = lsyms + i;
		      if (LDR_EXPORT (*l))
			{
			  char *expname = 0;
			  if (l->l_zeroes)
			    expname = l->l_name;
			  else if (l->l_offset < soldh.l_stlen)
			    expname = ldstrings + l->l_offset;
			  switch (is_ctor_dtor (expname))
			    {
			    case 3:
			      if (debug)
				fprintf (stderr, "\t%s\n", expname);
			      add_to_list (&constructors, expname);
			      break;

			    case 4:
			      add_to_list (&destructors, expname);
			      break;

			    default: /* not a constructor or destructor */
			      continue;
			    }
			}
		    }
		}
	      else
		fprintf (stderr, "%s: type = %04X flags = %04X\n", 
			 ah.ar_name, type, HEADER (libptr).f_flags);
	    }
	  while (ldclose (libptr) == FAILURE);
	  /* printf (stderr, "closed %s\n", soname); */
	}
    }
}
#endif /* XCOFF_SCAN_LIBS */

#endif /* OBJECT_FORMAT_COFF */


/*
 * OSF/rose specific stuff.
 */

#ifdef OBJECT_FORMAT_ROSE

/* Union of the various load commands */

typedef union load_union
{
  ldc_header_t			hdr;	/* common header */
  load_cmd_map_command_t	map;	/* map indexing other load cmds */
  interpreter_command_t		iprtr;	/* interpreter pathname */
  strings_command_t		str;	/* load commands strings section */
  region_command_t		region;	/* region load command */
  reloc_command_t		reloc;	/* relocation section */
  package_command_t		pkg;	/* package load command */
  symbols_command_t		sym;	/* symbol sections */
  entry_command_t		ent;	/* program start section */
  gen_info_command_t		info;	/* object information */
  func_table_command_t		func;	/* function constructors/destructors */
} load_union_t;

/* Structure to point to load command and data section in memory.  */

typedef struct load_all
{
  load_union_t *load;			/* load command */
  char *section;			/* pointer to section */
} load_all_t;

/* Structure to contain information about a file mapped into memory.  */

struct file_info
{
  char *start;				/* start of map */
  char *name;				/* filename */
  long	size;				/* size of the file */
  long  rounded_size;			/* size rounded to page boundary */
  int	fd;				/* file descriptor */
  int	rw;				/* != 0 if opened read/write */
  int	use_mmap;			/* != 0 if mmap'ed */
};

extern int decode_mach_o_hdr ();
extern int encode_mach_o_hdr ();

static void add_func_table	PROTO((mo_header_t *, load_all_t *,
				       symbol_info_t *, int));
static void print_header	PROTO((mo_header_t *));
static void print_load_command	PROTO((load_union_t*, size_t, int));
static void bad_header		PROTO((int));
static struct file_info	*read_file  PROTO((char *, int, int));
static void end_file		PROTO((struct file_info *));

/* OSF/rose specific version to scan the name list of the loaded
   program for the symbols g++ uses for static constructors and
   destructors.

   The constructor table begins at __CTOR_LIST__ and contains a count
   of the number of pointers (or -1 if the constructors are built in a
   separate section by the linker), followed by the pointers to the
   constructor functions, terminated with a null pointer.  The
   destructor table has the same format, and begins at __DTOR_LIST__.  */

static void
scan_prog_file (prog_name, which_pass)
     char *prog_name;
     enum pass which_pass;
{
  char *obj;
  mo_header_t hdr;
  load_all_t *load_array;
  load_all_t *load_end;
  load_all_t *load_cmd;
  int symbol_load_cmds;
  off_t offset;
  int i;
  int num_syms;
  int status;
  char *str_sect;
  struct file_info *obj_file;
  int prog_fd;
  mo_lcid_t cmd_strings	  = -1;
  symbol_info_t *main_sym = 0;
  int rw		  = (which_pass != PASS_FIRST);

  prog_fd = open (prog_name, (rw) ? O_RDWR : O_RDONLY);
  if (prog_fd < 0)
    fatal_perror ("can't read %s", prog_name);

  obj_file = read_file (prog_name, prog_fd, rw);
  obj = obj_file->start;

  status = decode_mach_o_hdr (obj, MO_SIZEOF_RAW_HDR, MOH_HEADER_VERSION, &hdr);
  if (status != MO_HDR_CONV_SUCCESS)
    bad_header (status);


  /* Do some basic sanity checks.  Note we explicitly use the big endian magic number,
     since the hardware will automatically swap bytes for us on loading little endian
     integers.  */

#ifndef CROSS_COMPILE
  if (hdr.moh_magic != MOH_MAGIC_MSB
      || hdr.moh_header_version != MOH_HEADER_VERSION
      || hdr.moh_byte_order != OUR_BYTE_ORDER
      || hdr.moh_data_rep_id != OUR_DATA_REP_ID
      || hdr.moh_cpu_type != OUR_CPU_TYPE
      || hdr.moh_cpu_subtype != OUR_CPU_SUBTYPE
      || hdr.moh_vendor_type != OUR_VENDOR_TYPE)
    {
      fatal ("incompatibilities between object file & expected values");
    }
#endif

  if (debug)
    print_header (&hdr);

  offset = hdr.moh_first_cmd_off;
  load_end = load_array
    = (load_all_t *) xcalloc (sizeof (load_all_t), hdr.moh_n_load_cmds + 2);

  /* Build array of load commands, calculating the offsets */
  for (i = 0; i < hdr.moh_n_load_cmds; i++)
    {
      load_union_t *load_hdr;		/* load command header */

      load_cmd = load_end++;
      load_hdr = (load_union_t *) (obj + offset);

      /* If modifying the program file, copy the header.  */
      if (rw)
	{
	  load_union_t *ptr = (load_union_t *) xmalloc (load_hdr->hdr.ldci_cmd_size);
	  bcopy ((char *)load_hdr, (char *)ptr, load_hdr->hdr.ldci_cmd_size);
	  load_hdr = ptr;

	  /* null out old command map, because we will rewrite at the end.  */
	  if (ptr->hdr.ldci_cmd_type == LDC_CMD_MAP)
	    {
	      cmd_strings = ptr->map.lcm_ld_cmd_strings;
	      ptr->hdr.ldci_cmd_type = LDC_UNDEFINED;
	    }
	}

      load_cmd->load = load_hdr;
      if (load_hdr->hdr.ldci_section_off > 0)
	load_cmd->section = obj + load_hdr->hdr.ldci_section_off;

      if (debug)
	print_load_command (load_hdr, offset, i);

      offset += load_hdr->hdr.ldci_cmd_size;
    }

  /* If the last command is the load command map and is not undefined,
     decrement the count of load commands.  */
  if (rw && load_end[-1].load->hdr.ldci_cmd_type == LDC_UNDEFINED)
    {
      load_end--;
      hdr.moh_n_load_cmds--;
    }

  /* Go through and process each symbol table section.  */
  symbol_load_cmds = 0;
  for (load_cmd = load_array; load_cmd < load_end; load_cmd++)
    {
      load_union_t *load_hdr = load_cmd->load;

      if (load_hdr->hdr.ldci_cmd_type == LDC_SYMBOLS)
	{
	  symbol_load_cmds++;

	  if (debug)
	    {
	      char *kind = "unknown";

	      switch (load_hdr->sym.symc_kind)
		{
		case SYMC_IMPORTS:	   kind = "imports"; break;
		case SYMC_DEFINED_SYMBOLS: kind = "defined"; break;
		case SYMC_STABS:	   kind = "stabs";   break;
		}

	      fprintf (stderr, "\nProcessing symbol table #%d, offset = 0x%.8lx, kind = %s\n",
		       symbol_load_cmds, load_hdr->hdr.ldci_section_off, kind);
	    }

	  if (load_hdr->sym.symc_kind != SYMC_DEFINED_SYMBOLS)
	    continue;

	  str_sect = load_array[load_hdr->sym.symc_strings_section].section;
	  if (str_sect == (char *)0)
	    fatal ("string section missing");

	  if (load_cmd->section == (char *)0)
	    fatal ("section pointer missing");

	  num_syms = load_hdr->sym.symc_nentries;
	  for (i = 0; i < num_syms; i++)
	    {
	      symbol_info_t *sym = ((symbol_info_t *) load_cmd->section) + i;
	      char *name = sym->si_name.symbol_name + str_sect;

	      if (name[0] != '_')
		continue;

	      if (rw)
		{
		  char *n = name + strlen (name) - strlen (NAME__MAIN);

		  if ((n - name) < 0 || strcmp (n, NAME__MAIN))
		    continue;
		  while (n != name)
		    if (*--n != '_')
		      continue;

		  main_sym = sym;
		}
	      else
		{
		  switch (is_ctor_dtor (name))
		    {
		    case 1:
		      add_to_list (&constructors, name);
		      break;

		    case 2:
		      add_to_list (&destructors, name);
		      break;

		    default:	/* not a constructor or destructor */
		      continue;
		    }
		}

	      if (debug)
		fprintf (stderr, "\ttype = 0x%.4x, sc = 0x%.2x, flags = 0x%.8x, name = %.30s\n",
			 sym->si_type, sym->si_sc_type, sym->si_flags, name);
	    }
	}
    }

  if (symbol_load_cmds == 0)
    fatal ("no symbol table found");

  /* Update the program file now, rewrite header and load commands.  At present,
     we assume that there is enough space after the last load command to insert
     one more.  Since the first section written out is page aligned, and the
     number of load commands is small, this is ok for the present.  */

  if (rw)
    {
      load_union_t *load_map;
      size_t size;

      if (cmd_strings == -1)
	fatal ("no cmd_strings found");

      /* Add __main to initializer list.
	 If we are building a program instead of a shared library, don't
	 do anything, since in the current version, you cannot do mallocs
	 and such in the constructors.  */

      if (main_sym != (symbol_info_t *)0
	  && ((hdr.moh_flags & MOH_EXECABLE_F) == 0))
	add_func_table (&hdr, load_array, main_sym, FNTC_INITIALIZATION);

      if (debug)
	fprintf (stderr, "\nUpdating header and load commands.\n\n");

      hdr.moh_n_load_cmds++;
      size = sizeof (load_cmd_map_command_t) + (sizeof (mo_offset_t) * (hdr.moh_n_load_cmds - 1));

      /* Create new load command map.  */
      if (debug)
	fprintf (stderr, "load command map, %d cmds, new size %ld.\n",
		 (int)hdr.moh_n_load_cmds, (long)size);

      load_map = (load_union_t *) xcalloc (1, size);
      load_map->map.ldc_header.ldci_cmd_type = LDC_CMD_MAP;
      load_map->map.ldc_header.ldci_cmd_size = size;
      load_map->map.lcm_ld_cmd_strings = cmd_strings;
      load_map->map.lcm_nentries = hdr.moh_n_load_cmds;
      load_array[hdr.moh_n_load_cmds-1].load = load_map;

      offset = hdr.moh_first_cmd_off;
      for (i = 0; i < hdr.moh_n_load_cmds; i++)
	{
	  load_map->map.lcm_map[i] = offset;
	  if (load_array[i].load->hdr.ldci_cmd_type == LDC_CMD_MAP)
	    hdr.moh_load_map_cmd_off = offset;

	  offset += load_array[i].load->hdr.ldci_cmd_size;
	}

      hdr.moh_sizeofcmds = offset - MO_SIZEOF_RAW_HDR;

      if (debug)
	print_header (&hdr);

      /* Write header */
      status = encode_mach_o_hdr (&hdr, obj, MO_SIZEOF_RAW_HDR);
      if (status != MO_HDR_CONV_SUCCESS)
	bad_header (status);

      if (debug)
	fprintf (stderr, "writing load commands.\n\n");

      /* Write load commands */
      offset = hdr.moh_first_cmd_off;
      for (i = 0; i < hdr.moh_n_load_cmds; i++)
	{
	  load_union_t *load_hdr = load_array[i].load;
	  size_t size = load_hdr->hdr.ldci_cmd_size;

	  if (debug)
	    print_load_command (load_hdr, offset, i);

	  bcopy ((char *)load_hdr, (char *)(obj + offset), size);
	  offset += size;
	}
    }

  end_file (obj_file);

  if (close (prog_fd))
    fatal_perror ("closing %s", prog_name);

  if (debug)
    fprintf (stderr, "\n");
}


/* Add a function table to the load commands to call a function
   on initiation or termination of the process.  */

static void
add_func_table (hdr_p, load_array, sym, type)
     mo_header_t *hdr_p;		/* pointer to global header */
     load_all_t *load_array;		/* array of ptrs to load cmds */
     symbol_info_t *sym;		/* pointer to symbol entry */
     int type;				/* fntc_type value */
{
  /* Add a new load command.  */
  int num_cmds = ++hdr_p->moh_n_load_cmds;
  int load_index = num_cmds - 1;
  size_t size = sizeof (func_table_command_t) + sizeof (mo_addr_t);
  load_union_t *ptr = xcalloc (1, size);
  load_all_t *load_cmd;
  int i;

  /* Set the unresolved address bit in the header to force the loader to be
     used, since kernel exec does not call the initialization functions.  */
  hdr_p->moh_flags |= MOH_UNRESOLVED_F;

  load_cmd = &load_array[load_index];
  load_cmd->load = ptr;
  load_cmd->section = (char *)0;

  /* Fill in func table load command.  */
  ptr->func.ldc_header.ldci_cmd_type = LDC_FUNC_TABLE;
  ptr->func.ldc_header.ldci_cmd_size = size;
  ptr->func.ldc_header.ldci_section_off = 0;
  ptr->func.ldc_header.ldci_section_len = 0;
  ptr->func.fntc_type = type;
  ptr->func.fntc_nentries = 1;

  /* copy address, turn it from abs. address to (region,offset) if necessary.  */
  /* Is the symbol already expressed as (region, offset)?  */
  if ((sym->si_flags & SI_ABSOLUTE_VALUE_F) == 0)
    {
      ptr->func.fntc_entry_loc[i].adr_lcid = sym->si_value.def_val.adr_lcid;
      ptr->func.fntc_entry_loc[i].adr_sctoff = sym->si_value.def_val.adr_sctoff;
    }

  /* If not, figure out which region it's in.  */
  else
    {
      mo_vm_addr_t addr = sym->si_value.abs_val;
      int found = 0;

      for (i = 0; i < load_index; i++)
	{
	  if (load_array[i].load->hdr.ldci_cmd_type == LDC_REGION)
	    {
	      region_command_t *region_ptr = &load_array[i].load->region;

	      if ((region_ptr->regc_flags & REG_ABS_ADDR_F) != 0
		  && addr >= region_ptr->regc_addr.vm_addr
		  && addr <= region_ptr->regc_addr.vm_addr + region_ptr->regc_vm_size)
		{
		  ptr->func.fntc_entry_loc[0].adr_lcid = i;
		  ptr->func.fntc_entry_loc[0].adr_sctoff = addr - region_ptr->regc_addr.vm_addr;
		  found++;
		  break;
		}
	    }
	}

      if (!found)
	fatal ("could not convert 0x%l.8x into a region", addr);
    }

  if (debug)
    fprintf (stderr,
	     "%s function, region %d, offset = %ld (0x%.8lx)\n",
	     (type == FNTC_INITIALIZATION) ? "init" : "term",
	     (int)ptr->func.fntc_entry_loc[i].adr_lcid,
	     (long)ptr->func.fntc_entry_loc[i].adr_sctoff,
	     (long)ptr->func.fntc_entry_loc[i].adr_sctoff);

}


/* Print the global header for an OSF/rose object.  */

static void
print_header (hdr_ptr)
     mo_header_t *hdr_ptr;
{
  fprintf (stderr, "\nglobal header:\n");
  fprintf (stderr, "\tmoh_magic            = 0x%.8lx\n", hdr_ptr->moh_magic);
  fprintf (stderr, "\tmoh_major_version    = %d\n", (int)hdr_ptr->moh_major_version);
  fprintf (stderr, "\tmoh_minor_version    = %d\n", (int)hdr_ptr->moh_minor_version);
  fprintf (stderr, "\tmoh_header_version   = %d\n", (int)hdr_ptr->moh_header_version);
  fprintf (stderr, "\tmoh_max_page_size    = %d\n", (int)hdr_ptr->moh_max_page_size);
  fprintf (stderr, "\tmoh_byte_order       = %d\n", (int)hdr_ptr->moh_byte_order);
  fprintf (stderr, "\tmoh_data_rep_id      = %d\n", (int)hdr_ptr->moh_data_rep_id);
  fprintf (stderr, "\tmoh_cpu_type         = %d\n", (int)hdr_ptr->moh_cpu_type);
  fprintf (stderr, "\tmoh_cpu_subtype      = %d\n", (int)hdr_ptr->moh_cpu_subtype);
  fprintf (stderr, "\tmoh_vendor_type      = %d\n", (int)hdr_ptr->moh_vendor_type);
  fprintf (stderr, "\tmoh_load_map_cmd_off = %d\n", (int)hdr_ptr->moh_load_map_cmd_off);
  fprintf (stderr, "\tmoh_first_cmd_off    = %d\n", (int)hdr_ptr->moh_first_cmd_off);
  fprintf (stderr, "\tmoh_sizeofcmds       = %d\n", (int)hdr_ptr->moh_sizeofcmds);
  fprintf (stderr, "\tmon_n_load_cmds      = %d\n", (int)hdr_ptr->moh_n_load_cmds);
  fprintf (stderr, "\tmoh_flags            = 0x%.8lx", (long)hdr_ptr->moh_flags);

  if (hdr_ptr->moh_flags & MOH_RELOCATABLE_F)
    fprintf (stderr, ", relocatable");

  if (hdr_ptr->moh_flags & MOH_LINKABLE_F)
    fprintf (stderr, ", linkable");

  if (hdr_ptr->moh_flags & MOH_EXECABLE_F)
    fprintf (stderr, ", execable");

  if (hdr_ptr->moh_flags & MOH_EXECUTABLE_F)
    fprintf (stderr, ", executable");

  if (hdr_ptr->moh_flags & MOH_UNRESOLVED_F)
    fprintf (stderr, ", unresolved");

  fprintf (stderr, "\n\n");
  return;
}


/* Print a short summary of a load command.  */

static void
print_load_command (load_hdr, offset, number)
     load_union_t *load_hdr;
     size_t offset;
     int number;
{
  mo_long_t type = load_hdr->hdr.ldci_cmd_type;
  char *type_str = (char *)0;

  switch (type)
    {
    case LDC_UNDEFINED:   type_str = "UNDEFINED";	break;
    case LDC_CMD_MAP:	  type_str = "CMD_MAP";		break;
    case LDC_INTERPRETER: type_str = "INTERPRETER";	break;
    case LDC_STRINGS:	  type_str = "STRINGS";		break;
    case LDC_REGION:	  type_str = "REGION";		break;
    case LDC_RELOC:	  type_str = "RELOC";		break;
    case LDC_PACKAGE:	  type_str = "PACKAGE";		break;
    case LDC_SYMBOLS:	  type_str = "SYMBOLS";		break;
    case LDC_ENTRY:	  type_str = "ENTRY";		break;
    case LDC_FUNC_TABLE:  type_str = "FUNC_TABLE";	break;
    case LDC_GEN_INFO:	  type_str = "GEN_INFO";	break;
    }

  fprintf (stderr,
	   "cmd %2d, sz: 0x%.2lx, coff: 0x%.3lx, doff: 0x%.6lx, dlen: 0x%.6lx",
	   number,
	   (long) load_hdr->hdr.ldci_cmd_size,
	   (long) offset,
	   (long) load_hdr->hdr.ldci_section_off,
	   (long) load_hdr->hdr.ldci_section_len);

  if (type_str == (char *)0)
    fprintf (stderr, ", ty: unknown (%ld)\n", (long) type);

  else if (type != LDC_REGION)
    fprintf (stderr, ", ty: %s\n", type_str);

  else
    {
      char *region = "";
      switch (load_hdr->region.regc_usage_type)
	{
	case REG_TEXT_T:	region = ", .text";	break;
	case REG_DATA_T:	region = ", .data";	break;
	case REG_BSS_T:		region = ", .bss";	break;
	case REG_GLUE_T:	region = ", .glue";	break;
#if defined (REG_RDATA_T) && defined (REG_SDATA_T) && defined (REG_SBSS_T) /*mips*/
	case REG_RDATA_T:	region = ", .rdata";	break;
	case REG_SDATA_T:	region = ", .sdata";	break;
	case REG_SBSS_T:	region = ", .sbss";	break;
#endif
	}

      fprintf (stderr, ", ty: %s, vaddr: 0x%.8lx, vlen: 0x%.6lx%s\n",
	       type_str,
	       (long) load_hdr->region.regc_vm_addr,
	       (long) load_hdr->region.regc_vm_size,
	       region);
    }

  return;
}


/* Fatal error when {en,de}code_mach_o_header fails.  */

static void
bad_header (status)
     int status;
{
  char *msg = (char *)0;

  switch (status)
    {
    case MO_ERROR_BAD_MAGIC:		msg = "bad magic number";		break;
    case MO_ERROR_BAD_HDR_VERS:		msg = "bad header version";		break;
    case MO_ERROR_BAD_RAW_HDR_VERS:	msg = "bad raw header version";		break;
    case MO_ERROR_BUF2SML:		msg = "raw header buffer too small";	break;
    case MO_ERROR_OLD_RAW_HDR_FILE:	msg = "old raw header file";		break;
    case MO_ERROR_UNSUPPORTED_VERS:	msg = "unsupported version";		break;
    }

  if (msg == (char *)0)
    fatal ("unknown {de,en}code_mach_o_hdr return value %d", status);
  else
    fatal ("%s", msg);
}


/* Read a file into a memory buffer.  */

static struct file_info *
read_file (name, fd, rw)
     char *name;		/* filename */
     int fd;			/* file descriptor */
     int rw;			/* read/write */
{
  struct stat stat_pkt;
  struct file_info *p = (struct file_info *) xcalloc (sizeof (struct file_info), 1);
#ifdef USE_MMAP
  static int page_size;
#endif

  if (fstat (fd, &stat_pkt) < 0)
    fatal_perror ("fstat %s", name);

  p->name	  = name;
  p->size	  = stat_pkt.st_size;
  p->rounded_size = stat_pkt.st_size;
  p->fd		  = fd;
  p->rw		  = rw;

#ifdef USE_MMAP
  if (debug)
    fprintf (stderr, "mmap %s, %s\n", name, (rw) ? "read/write" : "read-only");

  if (page_size == 0)
    page_size = sysconf (_SC_PAGE_SIZE);

  p->rounded_size = ((p->size + page_size - 1) / page_size) * page_size;
  p->start = mmap ((caddr_t)0,
		   (rw) ? p->rounded_size : p->size,
		   (rw) ? (PROT_READ | PROT_WRITE) : PROT_READ,
		   MAP_FILE | MAP_VARIABLE | MAP_SHARED,
		   fd,
		   0L);

  if (p->start != (char *)0 && p->start != (char *)-1)
    p->use_mmap = 1;

  else
#endif /* USE_MMAP */
    {
      long len;

      if (debug)
	fprintf (stderr, "read %s\n", name);

      p->use_mmap = 0;
      p->start = xmalloc (p->size);
      if (lseek (fd, 0L, SEEK_SET) < 0)
	fatal_perror ("lseek to 0 on %s", name);

      len = read (fd, p->start, p->size);
      if (len < 0)
	fatal_perror ("read %s", name);

      if (len != p->size)
	fatal ("read %ld bytes, expected %ld, from %s", len, p->size, name);
    }

  return p;
}

/* Do anything necessary to write a file back from memory.  */

static void
end_file (ptr)
     struct file_info *ptr;	/* file information block */
{
#ifdef USE_MMAP
  if (ptr->use_mmap)
    {
      if (ptr->rw)
	{
	  if (debug)
	    fprintf (stderr, "msync %s\n", ptr->name);

	  if (msync (ptr->start, ptr->rounded_size, MS_ASYNC))
	    fatal_perror ("msync %s", ptr->name);
	}

      if (debug)
	fprintf (stderr, "munmap %s\n", ptr->name);

      if (munmap (ptr->start, ptr->size))
	fatal_perror ("munmap %s", ptr->name);
    }
  else
#endif /* USE_MMAP */
    {
      if (ptr->rw)
	{
	  long len;

	  if (debug)
	    fprintf (stderr, "write %s\n", ptr->name);

	  if (lseek (ptr->fd, 0L, SEEK_SET) < 0)
	    fatal_perror ("lseek to 0 on %s", ptr->name);

	  len = write (ptr->fd, ptr->start, ptr->size);
	  if (len < 0)
	    fatal_perror ("write %s", ptr->name);

	  if (len != ptr->size)
	    fatal ("wrote %ld bytes, expected %ld, to %s", len, ptr->size, ptr->name);
	}

      free (ptr->start);
    }

  free (ptr);
}

#endif /* OBJECT_FORMAT_ROSE */