/* C code startup routine.
   Copyright (C) 1985, 1986 Free Software Foundation, Inc.

		       NO WARRANTY

  BECAUSE THIS PROGRAM IS LICENSED FREE OF CHARGE, WE PROVIDE ABSOLUTELY
NO WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW.  EXCEPT
WHEN OTHERWISE STATED IN WRITING, FREE SOFTWARE FOUNDATION, INC,
RICHARD M. STALLMAN AND/OR OTHER PARTIES PROVIDE THIS PROGRAM "AS IS"
WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY
AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE PROGRAM PROVE
DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR
CORRECTION.

 IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL RICHARD M.
STALLMAN, THE FREE SOFTWARE FOUNDATION, INC., AND/OR ANY OTHER PARTY
WHO MAY MODIFY AND REDISTRIBUTE THIS PROGRAM AS PERMITTED BELOW, BE
LIABLE TO YOU FOR DAMAGES, INCLUDING ANY LOST PROFITS, LOST MONIES, OR
OTHER SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
USE OR INABILITY TO USE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR
DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY THIRD PARTIES OR
A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS) THIS
PROGRAM, EVEN IF YOU HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH
DAMAGES, OR FOR ANY CLAIM BY ANY OTHER PARTY.

		GENERAL PUBLIC LICENSE TO COPY

  1. You may copy and distribute verbatim copies of this source file
as you receive it, in any medium, provided that you conspicuously
and appropriately publish on each copy a valid copyright notice
"Copyright (C) 1986 Richard M. Stallman"; and include following the
copyright notice a verbatim copy of the above disclaimer of warranty
and of this License.

  2. You may modify your copy or copies of this source file or
any portion of it, and copy and distribute such modifications under
the terms of Paragraph 1 above, provided that you also do the following:

    a) cause the modified files to carry prominent notices stating
    that you changed the files and the date of any change; and

    b) cause the whole of any work that you distribute or publish,
    that in whole or in part contains or is a derivative of this
    program or any part thereof, to be freely distributed
    and licensed to all third parties on terms identical to those
    contained in this License Agreement (except that you may choose
    to grant more extensive warranty protection to third parties,
    at your option).

  3. You may copy and distribute this program or any portion of it in
compiled, executable or object code form under the terms of Paragraphs
1 and 2 above provided that you do the following:

    a) cause each such copy to be accompanied by the
    corresponding machine-readable source code, which must
    be distributed under the terms of Paragraphs 1 and 2 above; or,

    b) cause each such copy to be accompanied by a
    written offer, with no time limit, to give any third party
    free (except for a nominal shipping charge) a machine readable
    copy of the corresponding source code, to be distributed
    under the terms of Paragraphs 1 and 2 above; or,

    c) in the case of a recipient of this program in compiled, executable
    or object code form (without the corresponding source code) you
    shall cause copies you distribute to be accompanied by a copy
    of the written offer of source code which you received along
    with the copy you received.

  4. You may not copy, sublicense, distribute or transfer this program
except as expressly provided under this License Agreement.  Any attempt
otherwise to copy, sublicense, distribute or transfer this program is void and
your rights to use the program under this License agreement shall be
automatically terminated.  However, parties who have received computer
software programs from you with this License Agreement will not have
their licenses terminated so long as such parties remain in full compliance.

In other words, you are welcome to use, share and improve this program.
You are forbidden to forbid anyone else to use, share and improve
what you give them.   Help stamp out software-hoarding!  */


/* The standard Vax 4.2 Unix crt0.c cannot be used for Emacs
   because it makes `envron' an initialized variable.
   It is easiest to have a special crt0.c on all machines
   though I don't know whether other machines actually need it.  */

/* On the vax and 68000, in BSD4.2 and USG5.2,
   this is the data format on startup:
  (vax) ap and fp are unpredictable as far as I know; don't use them.
  sp ->  word containing argc
         word pointing to first arg string
	 [word pointing to next arg string]... 0 or more times
	 0
Optionally:
	 [word pointing to environment variable]... 1 or more times
	 ...
	 0
And always:
	 first arg string
	 [next arg string]... 0 or more times
*/

/* On the 16000, at least in the one 4.2 system I know about,
  the initial data format is
  sp ->  word containing argc
         word containing argp
         word pointing to first arg string, and so on as above
*/

#include "config.h"

/*		********  WARNING ********
    Do not insert any data definitions before data_start!
    Since this is the first file linked, the address of the following
    variable should correspond to the start of initialized data space.
    On some systems this is a constant that is independent of the text
    size for shared executables.  On others, it is a function of the
    text size. In short, this seems to be the most portable way to
    discover the start of initialized data space dynamically at runtime,
    for either shared or unshared executables, on either swapping or
    virtual systems.  It only requires that the linker allocate objects
    in the order encountered, a reasonable model for most Unix systems.
    Similarly, note that the address of _start() should be the start
    of text space.   Fred Fish, UniSoft Systems Inc.  */
 
int data_start = 0;
   
#ifdef NEED_ERRNO
int errno = 0;
#endif

#ifndef DONT_NEED_ENVIRON 
char **environ;
#endif

#if defined(orion) || defined(pyramid) || defined(celerity) || defined(ALLIANT)

#ifdef ALLIANT
/* _start must initialize _curbrk and _minbrk on the first startup;
   when starting up after dumping, it must initialize them to what they were
   before the dumping, since they are in the shared library and
   are not dumped.  See ADJUST_EXEC_HEADER in m-alliant.h.  */
extern unsigned char *_curbrk, *_minbrk;
extern unsigned char end;
unsigned char *_setbrk = &end;
#endif

_start (argc, argv, envp)
     int argc;
     char **argv, **envp;
{
#ifdef ALLIANT
  _curbrk = _setbrk;
  _minbrk = _setbrk;
#endif

  environ = envp;

  exit (main (argc, argv, envp));
}

#endif /* orion or pyramid or celerity or alliant */

#if defined (ns16000) && !defined (sequent) && !defined (UMAX)

_start ()
{
/* On 16000, _start pushes fp onto stack */
  start1 ();
}

/* ignore takes care of skipping the fp value pushed in start.  */
static
start1 (ignore, argc, argv)
     int ignore;
     int argc;
     register char **argv;
{
  environ = argv + argc + 1;

  if (environ == *argv)
    environ--;
  exit (main (argc, argv, environ));
}
#endif /* ns16000, not sequent and not UMAX */

#ifdef UMAX
_start()
{
	asm("	exit []			# undo enter");
	asm("	.set	exitsc,1");
	asm("	.set	sigcatchall,0x400");

	asm("	.globl	_exit");
	asm("	.globl	start");
	asm("	.globl	__start");
	asm("	.globl	_main");
	asm("	.globl	_environ");
	asm("	.globl	_sigvec");
	asm("	.globl	sigentry");

	asm("start:");
	asm("	br	.xstart");
	asm("	.org	0x20");
	asm("	.double	p_glbl,0,0xf00000,0");
	asm("	.org	0x30");
	asm(".xstart:");
	asm("	adjspb	$8");
	asm("	movd	8(sp),0(sp)	# argc");
	asm("	addr	12(sp),r0");
	asm("	movd	r0,4(sp)	# argv");
	asm("L1:");
	asm("	movd	r0,r1");
	asm("	addqd	$4,r0");
	asm("	cmpqd	$0,0(r1)	# null args term ?");
	asm("	bne	L1");
	asm("	cmpd	r0,0(4(sp))	# end of 'env' or 'argv' ?");
	asm("	blt	L2");
	asm("	addqd	$-4,r0		# envp's are in list");
	asm("L2:");
	asm("	movd	r0,8(sp)	# env");
	asm("	movd	r0,@_environ	# indir is 0 if no env ; not 0 if env");
	asm("	movqd	$0,tos		# setup intermediate signal handler");
	asm("	addr	@sv,tos");
	asm("	movzwd	$sigcatchall,tos");
	asm("	jsr	@_sigvec");
	asm("	adjspb	$-12");
	asm("	jsr	@_main");
	asm("	adjspb	$-12");
	asm("	movd	r0,tos");
	asm("	jsr	@_exit");
	asm("	adjspb	$-4");
	asm("	addr	@exitsc,r0");
	asm("	svc");
	asm("	.align	4		# sigvec arg");
	asm("sv:");
	asm("	.double	sigentry");
	asm("	.double	0");
	asm("	.double	0");

	asm("	.comm	p_glbl,1");
}
#endif /* UMAX */

#ifdef CRT0_DUMMIES

/* Define symbol "start": here; some systems want that symbol.  */
#ifdef DOT_GLOBAL_START
asm("	.text		");
asm("	.globl start	");
asm("	start:		");
#endif /* DOT_GLOBAL_START */

#ifdef NODOT_GLOBAL_START
asm("	text		");
asm("	global start	");
asm("	start:		");
#endif /* NODOT_GLOBAL_START */

_start ()
{
/* On vax, nothing is pushed here  */
/* On sequent, bogus fp is pushed here  */
  start1 ();
}

static
start1 (CRT0_DUMMIES argc, xargv)
     int argc;
     char *xargv;
{
  register char **argv = &xargv;
  environ = argv + argc + 1;

  if ((char *)environ == xargv)
    environ--;
  exit (main (argc, argv, environ));
}
#else /* not CRT0_DUMMIES */

/* "m68k" and "m68000" both stand for m68000 processors,
   but with different program-entry conventions.
   This is a kludge.  Now that the CRT0_DUMMIES mechanism above exists,
   most of these machines could use the vax code above
   with some suitable definition of CRT0_DUMMIES.
   Then the symbol m68k could be flushed.
   But I don't want to risk breaking these machines
   in a version 17 patch release, so that change is being put off.  */

#ifdef m68k			/* Can't do it all from C */
	asm ("	global	_start");
	asm ("	text");
	asm ("_start:");
#ifndef NU
#ifdef STRIDE
	asm ("	comm	havefpu%,2");
#else /* m68k, not STRIDE */
	asm ("	data");
	asm ("	even");
	asm ("	global	splimit%");
	asm ("splimit%:");
	asm ("	space 4");
#endif /* STRIDE */
	asm ("	global	exit");
	asm ("	text");
#ifdef STRIDE
	asm ("	trap	&3");
	asm ("	mov.w	%d0,havefpu%");
#else /* m68k, not STRIDE */
  	asm ("	mov.l	%d0,splimit%");
#endif /* STRIDE */
#endif /* not NU */
	asm ("	jsr	start1");
	asm ("	mov.l	%d0,(%sp)");
	asm ("	jsr	exit");
	asm ("	mov.l	&1,%d0");	/* d0 = 1 => exit */
	asm ("	trap	&0");
#else /* m68000, not m68k */

#ifdef m68000
  
#ifdef ISI68K
	asm ("	.text");
	asm ("	.globl	__start");
	asm ("__start:");
	asm ("	.word 0");
	asm ("	link	fp,#0");
	asm ("	jbsr	_start1");
	asm ("	unlk	fp");
	asm ("	rts");
#else /* not ISI68K */

_start ()
{
/* On 68000, _start pushes a6 onto stack  */
  start1 ();
}
#endif /* not ISI68k */
#endif /* m68000 */
#endif /* m68k */

#if defined(m68k) || defined(m68000)
/* ignore takes care of skipping the a6 value pushed in start.  */
static
#if defined(m68k)
start1 (argc, xargv)
#else
start1 (ignore, argc, xargv)
#endif
     int argc;
     char *xargv;
{
  register char **argv = &xargv;
  environ = argv + argc + 1;

  if ((char *)environ == xargv)
    environ--;
  exit (main (argc, argv, environ));
}

#endif /* m68k or m68000 */

#endif /* not CRT0_DUMMIES */

#ifdef hp9000
int argc_value;
char **argv_value;
#ifdef OLD_HP_ASSEMBLER
	asm("   text");
	asm("	globl __start");
	asm("	globl _exit");
	asm("	globl _main");
	asm("__start");
	asm("	dc.l	0");
	asm("	subq.w	#0x1,d0");
	asm("	move.w	d0,float_soft");
	asm("	move.l	0x4(a7),d0");
	asm("	beq.s	skip_1");
	asm("	move.l	d0,a0");
	asm("	clr.l	-0x4(a0)");
	asm("skip_1");
	asm("	move.l	a7,a0");
	asm("	subq.l	#0x8,a7");
	asm("	move.l	(a0),(a7)");
	asm("	move.l	(a0),_argc_value");
	asm("	addq.l	#0x4,a0");
	asm("	move.l	a0,0x4(a7)");
	asm("	move.l	a0,_argv_value");
	asm("incr_loop");
	asm("	tst.l	(a0)+");
	asm("	bne.s	incr_loop");
	asm("	move.l	0x4(a7),a1");
	asm("	cmp.l	(a1),a0");
	asm("	blt.s	skip_2");
	asm("	subq.l	#0x4,a0");
	asm("skip_2");
	asm("	move.l	a0,0x8(a7)");
	asm("	move.l	a0,_environ");
	asm("	jsr	_main");
	asm("	addq.l	#0x8,a7");
	asm("	move.l	d0,-(a7)");
	asm("	jsr	_exit");
	asm("	move.w	#0x1,d0");
	asm("	trap	#0x0");
	asm("	comm	float_soft,4");
/* float_soft is allocated in this way because C would
   put an underscore character in its name otherwise. */ 

#else /* new hp assembler */

	asm("	text");
	asm("	global	__start");
	asm("	global	_exit");
	asm("	global	_main");
	asm("__start:");
	asm("	byte	0,0,0,0");
	asm("	subq.w	&1,%d0");
	asm("	mov.w	%d0,float_soft");
	asm("	mov.w	%d1,flag_68881");
	asm("	beq.b	skip_float"); 
	asm("	fmov.l	&0x7480,%fpcr");
	asm("skip_float:");
	asm("	mov.l	4(%a7),%d0");
	asm("	beq.b	skip_1");
	asm("	mov.l	%d0,%a0");
	asm("	clr.l	-4(%a0)");
	asm("skip_1:");
	asm("	mov.l	%a7,%a0");
	asm("	subq.l	&8,%a7");
	asm("	mov.l	(%a0),(%a7)");
	asm("	mov.l	(%a0),_argc_value");
	asm("	addq.l	&4,%a0");
	asm("	mov.l	%a0,4(%a7)");
	asm("	mov.l	%a0,_argv_value");
	asm("incr_loop:");
	asm("	tst.l	(%a0)+");
	asm("	bne.b	incr_loop");
	asm("	mov.l	4(%a7),%a1");
	asm("	cmp.l	%a0,(%a1)");
	asm("	blt.b	skip_2");
	asm("	subq.l	&4,%a0");
	asm("skip_2:");
	asm("	mov.l	%a0,8(%a7)");
	asm("	mov.l	%a0,_environ");
	asm("	jsr	_main");
	asm("	addq.l	&8,%a7");
	asm("	mov.l	%d0,-(%a7)");
	asm("	jsr	_exit");
	asm("	mov.w	&1,%d0");
	asm("	trap	&0");
	asm("	comm	float_soft, 4");
	asm("	comm	flag_68881, 4");
	
#endif /* new hp assembler */
#endif /* hp9000 */

#ifdef GOULD

/* startup code has to be in near text rather
   than fartext as allocated by the C compiler. */
	asm("	.text");
	asm("	.align	2");
	asm("	.globl	__start");
	asm("	.text");
	asm("__start:");
/* setup base register b1 (function base). */
	asm("	.using	b1,.");
	asm("	tpcbr	b1");
/* setup base registers b3 through b7 (data references). */
	asm("	file	basevals,b3");
/* setup base register b2 (stack pointer); it should be
   aligned on a 8-word boundary; but because it is pointing
   to argc, its value should be remembered (in r5). */
	asm("	movw	b2,r4");
	asm("	movw	b2,r5");
	asm("	andw	#~0x1f,r4");
	asm("	movw	r4,b2");
/* allocate stack frame to do some work. */
	asm("	subea	16w,b2");
/* initialize signal catching for UTX/32 1.2; this is 
   necessary to make restart from saved image work. */
	asm("	movea	sigcatch,r1");
	asm("	movw	r1,8w[b2]");
	asm("	svc	#1,#150");
/* setup address of argc for start1. */
	asm("	movw	r5,8w[b2]");
	asm("   func	#1,_start1");
	asm("	halt");
/* space for ld to store base register initial values. */
	asm("	.align	5");
	asm("basevals:");
	asm("	.word	__base3,__base4,__base5,__base6,__base7");

static
start1 (xargc)
     int *xargc;
{
  register int	argc;
  register char **argv;

  argc = *xargc;
  argv = (char **)(xargc) + 1;
  environ = argv + argc + 1;

  if (environ == argv)
    environ--;
  exit (main (argc, argv, environ));

}

#endif /* GOULD */

#ifdef elxsi
extern int errno;
extern char **environ;

_start()
{
  register int r;
  
  errno = 0;
  environ = *(&environ + 8);
  _stdinit();
  r = main(*(&environ + 6), *(&environ + 7), environ);
  exit(r);
  _exit(r);
}
#endif /* elxsi */

  
