src/ecrt0.c

   1 /* C code startup routine.
   2    Copyright (C) 1985, 1986, 1992 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 /* The standard Vax 4.2 Unix crt0.c cannot be used for Emacs
  23    because it makes `environ' an initialized variable.
  24    It is easiest to have a special crt0.c on all machines
  25    though I don't know whether other machines actually need it.  */
  26
  27 /* On the vax and 68000, in BSD4.2 and USG5.2,
  28    this is the data format on startup:
  29   (vax) ap and fp are unpredictable as far as I know; don't use them.
  30   sp ->  word containing argc
  31          word pointing to first arg string
  32          [word pointing to next arg string]... 0 or more times
  33          0
  34 Optionally:
  35          [word pointing to environment variable]... 1 or more times
  36          ...
  37          0
  38 And always:
  39          first arg string
  40          [next arg string]... 0 or more times
  41 */
  42
  43 /* On the 16000, at least in the one 4.2 system I know about,
  44   the initial data format is
  45   sp ->  word containing argc
  46          word containing argp
  47          word pointing to first arg string, and so on as above
  48 */
  49
  50 #ifdef emacs
  51 #include <config.h>
  52 #endif
  53
  54 /*              ********  WARNING ********
  55     Do not insert any data definitions before data_start!
  56     Since this is the first file linked, the address of the following
  57     variable should correspond to the start of initialized data space.
  58     On some systems this is a constant that is independent of the text
  59     size for shared executables.  On others, it is a function of the
  60     text size. In short, this seems to be the most portable way to
  61     discover the start of initialized data space dynamically at runtime,
  62     for either shared or unshared executables, on either swapping or
  63     virtual systems.  It only requires that the linker allocate objects
  64     in the order encountered, a reasonable model for most Unix systems.
  65     Similarly, note that the address of _start() should be the start
  66     of text space.   Fred Fish, UniSoft Systems Inc.  */
  67
  68 int data_start = 0;
  69
  70 #ifdef NEED_ERRNO
  71 int errno;
  72 #endif
  73
  74 #ifndef DONT_NEED_ENVIRON
  75 char **environ;
  76 #endif
  77
  78 #ifndef static
  79 /* On systems where the static storage class is usable, this function
  80    should be declared as static.  Otherwise, the static keyword has
  81    been defined to be something else, and code for those systems must
  82    take care of this declaration appropriately.  */
  83 static start1 ();
  84 #endif
  85
  86 #ifdef APOLLO
  87 extern  char   *malloc(), *realloc(), *(*_libc_malloc) (), *(*_libc_realloc)();
  88 extern  void    free(), (*_libc_free) (); extern int main();
  89 std_$call void  unix_$main();
  90
  91 _start()
  92 {
  93         _libc_malloc = malloc;
  94         _libc_realloc = realloc;
  95         _libc_free = free;
  96         unix_$main(main);       /* no return */
  97 }
  98 #endif /* APOLLO */
  99
 100 #if defined(orion) || defined(pyramid) || defined(celerity) || defined(ALLIANT) || defined(clipper) || defined(sps7)
 101
 102 #if defined(sps7) && defined(V3x)
 103         asm("   section 10");
 104         asm("   ds.b    0xb0");
 105 #endif
 106
 107 #ifdef ALLIANT
 108 /* _start must initialize _curbrk and _minbrk on the first startup;
 109    when starting up after dumping, it must initialize them to what they were
 110    before the dumping, since they are in the shared library and
 111    are not dumped.  See ADJUST_EXEC_HEADER in m-alliant.h.  */
 112 extern unsigned char *_curbrk, *_minbrk;
 113 extern unsigned char end;
 114 unsigned char *_setbrk = &end;
 115 #ifdef ALLIANT_2800
 116 unsigned char *_end = &end;
 117 #endif
 118 #endif
 119
 120 #ifndef DUMMIES
 121 #define DUMMIES
 122 #endif
 123
 124 _start (DUMMIES argc, argv, envp)
 125      int argc;
 126      char **argv, **envp;
 127 {
 128 #ifdef ALLIANT
 129 #ifdef ALLIANT_2800
 130   _curbrk = _end;
 131   _minbrk = _end;
 132 #else
 133   _curbrk = _setbrk;
 134   _minbrk = _setbrk;
 135 #endif
 136 #endif
 137
 138   environ = envp;
 139
 140   exit (main (argc, argv, envp));
 141 }
 142
 143 #endif /* orion or pyramid or celerity or alliant or clipper */
 144
 145 #if defined (ns16000) && !defined (sequent) && !defined (UMAX) && !defined (CRT0_DUMMIES)
 146
 147 _start ()
 148 {
 149 /* On 16000, _start pushes fp onto stack */
 150   start1 ();
 151 }
 152
 153 /* ignore takes care of skipping the fp value pushed in start.  */
 154 static
 155 start1 (ignore, argc, argv)
 156      int ignore;
 157      int argc;
 158      register char **argv;
 159 {
 160   environ = argv + argc + 1;
 161
 162   if (environ == *argv)
 163     environ--;
 164   exit (main (argc, argv, environ));
 165 }
 166 #endif /* ns16000, not sequent and not UMAX, and not the CRT0_DUMMIES method */
 167
 168 #ifdef UMAX
 169 _start()
 170 {
 171         asm("   exit []                 # undo enter");
 172         asm("   .set    exitsc,1");
 173         asm("   .set    sigcatchall,0x400");
 174
 175         asm("   .globl  _exit");
 176         asm("   .globl  start");
 177         asm("   .globl  __start");
 178         asm("   .globl  _main");
 179         asm("   .globl  _environ");
 180         asm("   .globl  _sigvec");
 181         asm("   .globl  sigentry");
 182
 183         asm("start:");
 184         asm("   br      .xstart");
 185         asm("   .org    0x20");
 186         asm("   .double p_glbl,0,0xf00000,0");
 187         asm("   .org    0x30");
 188         asm(".xstart:");
 189         asm("   adjspb  $8");
 190         asm("   movd    8(sp),0(sp)     # argc");
 191         asm("   addr    12(sp),r0");
 192         asm("   movd    r0,4(sp)        # argv");
 193         asm("L1:");
 194         asm("   movd    r0,r1");
 195         asm("   addqd   $4,r0");
 196         asm("   cmpqd   $0,0(r1)        # null args term ?");
 197         asm("   bne     L1");
 198         asm("   cmpd    r0,0(4(sp))     # end of 'env' or 'argv' ?");
 199         asm("   blt     L2");
 200         asm("   addqd   $-4,r0          # envp's are in list");
 201         asm("L2:");
 202         asm("   movd    r0,8(sp)        # env");
 203         asm("   movd    r0,@_environ    # indir is 0 if no env ; not 0 if env");
 204         asm("   movqd   $0,tos          # setup intermediate signal handler");
 205         asm("   addr    @sv,tos");
 206         asm("   movzwd  $sigcatchall,tos");
 207         asm("   jsr     @_sigvec");
 208         asm("   adjspb  $-12");
 209         asm("   jsr     @_main");
 210         asm("   adjspb  $-12");
 211         asm("   movd    r0,tos");
 212         asm("   jsr     @_exit");
 213         asm("   adjspb  $-4");
 214         asm("   addr    @exitsc,r0");
 215         asm("   svc");
 216         asm("   .align  4               # sigvec arg");
 217         asm("sv:");
 218         asm("   .double sigentry");
 219         asm("   .double 0");
 220         asm("   .double 0");
 221
 222         asm("   .comm   p_glbl,1");
 223 }
 224 #endif /* UMAX */
 225
 226 #ifdef CRT0_DUMMIES
 227
 228 /* Define symbol "start": here; some systems want that symbol.  */
 229 #ifdef DOT_GLOBAL_START
 230 asm("   .text           ");
 231 asm("   .globl start    ");
 232 asm("   start:          ");
 233 #endif /* DOT_GLOBAL_START */
 234
 235 #ifdef NODOT_GLOBAL_START
 236 asm("   text            ");
 237 asm("   global start    ");
 238 asm("   start:          ");
 239 #endif /* NODOT_GLOBAL_START */
 240
 241 #ifdef m68000
 242
 243 /* GCC 2.1, when optimization is turned off, seems to want to push a
 244    word of garbage on the stack, which screws up the CRT0_DUMMIES
 245    hack.  So we hand-code _start in assembly language.  */
 246 asm(".text                      ");
 247 asm("   .even                   ");
 248 asm(".globl __start             ");
 249 asm("__start:                   ");
 250 asm("   link a6,#0              ");
 251 asm("   jbsr _start1            ");
 252 asm("   unlk a6                 ");
 253 asm("   rts                     ");
 254
 255 #else /* not m68000 */
 256
 257 _start ()
 258 {
 259 /* On vax, nothing is pushed here  */
 260 /* On sequent, bogus fp is pushed here  */
 261   start1 ();
 262 }
 263
 264 #endif /* possibly m68000 */
 265
 266 static
 267 start1 (CRT0_DUMMIES argc, xargv)
 268      int argc;
 269      char *xargv;
 270 {
 271   register char **argv = &xargv;
 272   environ = argv + argc + 1;
 273
 274   if ((char *)environ == xargv)
 275     environ--;
 276   exit (main (argc, argv, environ));
 277
 278   /* Refer to `start1' so GCC will not think it is never called
 279      and optimize it out.  */
 280   (void) &start1;
 281 }
 282 #else /* not CRT0_DUMMIES */
 283
 284 /* "m68k" and "m68000" both stand for m68000 processors,
 285    but with different program-entry conventions.
 286    This is a kludge.  Now that the CRT0_DUMMIES mechanism above exists,
 287    most of these machines could use the vax code above
 288    with some suitable definition of CRT0_DUMMIES.
 289    Then the symbol m68k could be flushed.
 290    But I don't want to risk breaking these machines
 291    in a version 17 patch release, so that change is being put off.  */
 292
 293 #ifdef m68k                     /* Can't do it all from C */
 294         asm ("  global  _start");
 295         asm ("  text");
 296         asm ("_start:");
 297 #ifndef NU
 298 #ifdef STRIDE
 299         asm ("  comm    havefpu%,2");
 300 #else /* m68k, not STRIDE */
 301         asm ("  comm    splimit%,4");
 302 #endif /* STRIDE */
 303         asm ("  global  exit");
 304         asm ("  text");
 305 #ifdef STRIDE
 306         asm ("  trap    &3");
 307         asm ("  mov.w   %d0,havefpu%");
 308 #else /* m68k, not STRIDE */
 309         asm ("  mov.l   %d0,splimit%");
 310 #endif /* STRIDE */
 311 #endif /* not NU */
 312         asm ("  jsr     start1");
 313         asm ("  mov.l   %d0,(%sp)");
 314         asm ("  jsr     exit");
 315         asm ("  mov.l   &1,%d0");       /* d0 = 1 => exit */
 316         asm ("  trap    &0");
 317 #else /* m68000, not m68k */
 318
 319 #ifdef m68000
 320
 321 #ifdef ISI68K
 322 /* Added by ESM Sun May 24 12:44:02 1987 to get new ISI library to work */
 323 /* Edited by Ray Mon May 15 15:59:56 EST 1989 so we can compile with gcc */
 324 #if defined(BSD4_3) && !defined(__GNUC__)
 325 static foo () {
 326 #endif
 327         asm ("  .globl  is68020");
 328         asm ("is68020:");
 329 #ifndef BSD4_3
 330         asm ("  .long   0x00000000");
 331         asm ("  .long   0xffffffff");
 332 /* End of stuff added by ESM */
 333 #endif
 334         asm ("  .text");
 335         asm ("  .globl  __start");
 336         asm ("__start:");
 337         asm ("  .word 0");
 338         asm ("  link    a6,#0");
 339         asm ("  jbsr    _start1");
 340         asm ("  unlk    a6");
 341         asm ("  rts");
 342 #if defined(BSD4_3) && !defined(__GNUC__)
 343       }
 344 #endif
 345 #else /* not ISI68K */
 346
 347 _start ()
 348 {
 349 #ifdef sun
 350   finitfp_();
 351 #endif
 352 /* On 68000, _start pushes a6 onto stack  */
 353   start1 ();
 354 }
 355 #endif /* not ISI68k */
 356 #endif /* m68000 */
 357 #endif /* m68k */
 358
 359 #if defined(m68k) || defined(m68000)
 360 /* ignore takes care of skipping the a6 value pushed in start.  */
 361 static
 362 #if defined(m68k)
 363 start1 (argc, xargv)
 364 #else
 365 start1 (ignore, argc, xargv)
 366 #endif
 367      int argc;
 368      char *xargv;
 369 {
 370   register char **argv = &xargv;
 371   environ = argv + argc + 1;
 372
 373   if ((char *)environ == xargv)
 374     environ--;
 375 #ifdef sun_68881
 376   asm("    jsr     f68881_used");
 377 #endif
 378 #ifdef sun_fpa
 379   asm("    jsr     ffpa_used");
 380 #endif
 381 #ifdef sun_soft
 382   asm("    jsr     start_float");
 383 #endif
 384   exit (main (argc, argv, environ));
 385 }
 386
 387 #endif /* m68k or m68000 */
 388
 389 #endif /* not CRT0_DUMMIES */
 390
 391 #ifdef hp9000s300
 392 int argc_value;
 393 char **argv_value;
 394 #ifdef OLD_HP_ASSEMBLER
 395         asm("   text");
 396         asm("   globl __start");
 397         asm("   globl _exit");
 398         asm("   globl _main");
 399         asm("__start");
 400         asm("   dc.l    0");
 401         asm("   subq.w  #0x1,d0");
 402         asm("   move.w  d0,float_soft");
 403         asm("   move.l  0x4(a7),d0");
 404         asm("   beq.s   skip_1");
 405         asm("   move.l  d0,a0");
 406         asm("   clr.l   -0x4(a0)");
 407         asm("skip_1");
 408         asm("   move.l  a7,a0");
 409         asm("   subq.l  #0x8,a7");
 410         asm("   move.l  (a0),(a7)");
 411         asm("   move.l  (a0),_argc_value");
 412         asm("   addq.l  #0x4,a0");
 413         asm("   move.l  a0,0x4(a7)");
 414         asm("   move.l  a0,_argv_value");
 415         asm("incr_loop");
 416         asm("   tst.l   (a0)+");
 417         asm("   bne.s   incr_loop");
 418         asm("   move.l  0x4(a7),a1");
 419         asm("   cmp.l   (a1),a0");
 420         asm("   blt.s   skip_2");
 421         asm("   subq.l  #0x4,a0");
 422         asm("skip_2");
 423         asm("   move.l  a0,0x8(a7)");
 424         asm("   move.l  a0,_environ");
 425         asm("   jsr     _main");
 426         asm("   addq.l  #0x8,a7");
 427         asm("   move.l  d0,-(a7)");
 428         asm("   jsr     _exit");
 429         asm("   move.w  #0x1,d0");
 430         asm("   trap    #0x0");
 431         asm("   comm    float_soft,4");
 432 /* float_soft is allocated in this way because C would
 433    put an underscore character in its name otherwise. */
 434
 435 #else /* new hp assembler */
 436
 437         asm("   text");
 438         asm("   global  float_loc");
 439         asm("   set     float_loc,0xFFFFB000");
 440         asm("   global  fpa_loc");
 441         asm("   set     fpa_loc,0xfff08000");
 442         asm("   global  __start");
 443         asm("   global  _exit");
 444         asm("   global  _main");
 445         asm("__start:");
 446         asm("   byte    0,0,0,0");
 447         asm("   subq.w  &1,%d0");
 448         asm("   mov.w   %d0,float_soft");
 449         asm("   mov.w   %d1,flag_68881");
 450 #ifndef HPUX_68010
 451         asm("   beq.b   skip_float");
 452         asm("   fmov.l  &0x7400,%fpcr");
 453 /*      asm("   fmov.l  &0x7480,%fpcr"); */
 454 #endif /* HPUX_68010 */
 455         asm("skip_float:");
 456         asm("   mov.l   %a0,%d0");
 457         asm("   add.l   %d0,%d0");
 458         asm("   subx.w  %d1,%d1");
 459         asm("   mov.w   %d1,flag_68010");
 460         asm("   add.l   %d0,%d0");
 461         asm("   subx.w  %d1,%d1");
 462         asm("   mov.w   %d1,flag_fpa");
 463         asm("   tst.l   %d2");
 464         asm("   ble.b   skip_3");
 465         asm("   lsl     flag_68881");
 466         asm("   lsl     flag_fpa");
 467         asm("skip_3:");
 468         asm("   mov.l   4(%a7),%d0");
 469         asm("   beq.b   skip_1");
 470         asm("   mov.l   %d0,%a0");
 471         asm("   clr.l   -4(%a0)");
 472         asm("skip_1:");
 473         asm("   mov.l   %a7,%a0");
 474         asm("   subq.l  &8,%a7");
 475         asm("   mov.l   (%a0),(%a7)");
 476         asm("   mov.l   (%a0),_argc_value");
 477         asm("   addq.l  &4,%a0");
 478         asm("   mov.l   %a0,4(%a7)");
 479         asm("   mov.l   %a0,_argv_value");
 480         asm("incr_loop:");
 481         asm("   tst.l   (%a0)+");
 482         asm("   bne.b   incr_loop");
 483         asm("   mov.l   4(%a7),%a1");
 484         asm("   cmp.l   %a0,(%a1)");
 485         asm("   blt.b   skip_2");
 486         asm("   subq.l  &4,%a0");
 487         asm("skip_2:");
 488         asm("   mov.l   %a0,8(%a7)");
 489         asm("   mov.l   %a0,_environ");
 490         asm("   jsr     _main");
 491         asm("   addq.l  &8,%a7");
 492         asm("   mov.l   %d0,-(%a7)");
 493         asm("   jsr     _exit");
 494         asm("   mov.w   &1,%d0");
 495         asm("   trap    &0");
 496         asm("   comm    float_soft, 4");
 497         asm("   comm    flag_68881, 4");
 498         asm("   comm    flag_68010, 4");
 499         asm("   comm    flag_68040, 4");
 500         asm("   comm    flag_fpa, 4");
 501
 502 #endif /* new hp assembler */
 503 #endif /* hp9000s300 */
 504
 505 #ifdef GOULD
 506
 507 /* startup code has to be in near text rather
 508    than fartext as allocated by the C compiler. */
 509         asm("   .text");
 510         asm("   .align  2");
 511         asm("   .globl  __start");
 512         asm("   .text");
 513         asm("__start:");
 514 /* setup base register b1 (function base). */
 515         asm("   .using  b1,.");
 516         asm("   tpcbr   b1");
 517 /* setup base registers b3 through b7 (data references). */
 518         asm("   file    basevals,b3");
 519 /* setup base register b2 (stack pointer); it should be
 520    aligned on a 8-word boundary; but because it is pointing
 521    to argc, its value should be remembered (in r5). */
 522         asm("   movw    b2,r4");
 523         asm("   movw    b2,r5");
 524         asm("   andw    #~0x1f,r4");
 525         asm("   movw    r4,b2");
 526 /* allocate stack frame to do some work. */
 527         asm("   subea   16w,b2");
 528 /* initialize signal catching for UTX/32 1.2; this is
 529    necessary to make restart from saved image work. */
 530         asm("   movea   sigcatch,r1");
 531         asm("   movw    r1,8w[b2]");
 532         asm("   svc     #1,#150");
 533 /* setup address of argc for start1. */
 534         asm("   movw    r5,8w[b2]");
 535         asm("   func    #1,_start1");
 536         asm("   halt");
 537 /* space for ld to store base register initial values. */
 538         asm("   .align  5");
 539         asm("basevals:");
 540         asm("   .word   __base3,__base4,__base5,__base6,__base7");
 541
 542 static
 543 start1 (xargc)
 544      int *xargc;
 545 {
 546   register int  argc;
 547   register char **argv;
 548
 549   argc = *xargc;
 550   argv = (char **)(xargc) + 1;
 551   environ = argv + argc + 1;
 552
 553   if (environ == argv)
 554     environ--;
 555   exit (main (argc, argv, environ));
 556
 557 }
 558
 559 #endif /* GOULD */
 560
 561 #ifdef elxsi
 562 #include <elxsi/argvcache.h>
 563
 564 extern char **environ;
 565 extern int      errno;
 566 extern void     _init_doscan(), _init_iob();
 567 extern char     end[];
 568 char            *_init_brk = end;
 569
 570 _start()
 571 {
 572   environ = exec_cache.ac_envp;
 573   brk (_init_brk);
 574   errno = 0;
 575   _init_doscan ();
 576   _init_iob ();
 577   _exit (exit (main (exec_cache.ac_argc,
 578                      exec_cache.ac_argv,
 579                      exec_cache.ac_envp)));
 580 }
 581 #endif /* elxsi */
 582
 583
 584 #ifdef sparc
 585 asm (".global __start");
 586 asm (".text");
 587 asm ("__start:");
 588 asm ("  mov     0, %fp");
 589 asm ("  ld      [%sp + 64], %o0");
 590 asm ("  add     %sp, 68, %o1");
 591 asm ("  sll     %o0, 2, %o2");
 592 asm ("  add     %o2, 4, %o2");
 593 asm ("  add     %o1, %o2, %o2");
 594 asm ("  sethi   %hi(_environ), %o3");
 595 asm ("  st      %o2, [%o3+%lo(_environ)]");
 596 asm ("  andn    %sp, 7, %sp");
 597 asm ("  call    _main");
 598 asm ("  sub     %sp, 24, %sp");
 599 asm ("  call    __exit");
 600 asm ("  nop");
 601
 602 #endif /* sparc */
 603
 604 #if __FreeBSD__ == 2
 605 char *__progname;
 606 #endif
 607 #ifdef __bsdi__
 608 #include <sys/param.h> /* for version number */
 609 #if defined(_BSDI_VERSION) && (_BSDI_VERSION >= 199501)
 610 char *__progname;
 611 #endif
 612 #endif /* __bsdi__ */