compilers/linux86-0.16.17/libc/msdos/msdos.c

   1 /* Copyright (C) 1995,1996 Robert de Bath <rdebath@cix.compulink.co.uk>
   2  * This file is part of the Linux-8086 C library and is distributed
   3  * under the GNU Library General Public License.
   4  */
   5
   6 #if !__FIRST_ARG_IN_AX__
   7 #ifdef __AS386_16__
   8 #ifdef __MSDOS__
   9
  10 #include <dos.h>
  11 #include <fcntl.h>
  12 #include <errno.h>
  13 int errno;
  14 unsigned _doserrno;
  15
  16 #ifdef L_dos_start
  17
  18 static char * defarg[2] = { "C" };
  19 static char ** def_environ =defarg+1;
  20 void (*__cleanup)() = 0;
  21
  22 #asm
  23   .data
  24 export ___envseg
  25 ___envseg:
  26   .word 0
  27
  28 export ___psp
  29 ___psp:
  30   .word 0
  31
  32   .text
  33
  34 export _exit
  35 export __exit
  36 _exit:                  ! exit(rv) function
  37   mov   bx,sp
  38   push  [bx+2]          ! Copy the `rv` for the exit fuctions.
  39   mov   bx,[___cleanup] ! Call exit, normally this is `__do_exit`
  40   test  bx,bx
  41   je    no_clean        ! But it`s default is null
  42   call  bx
  43 no_clean:
  44   inc   sp
  45   inc   sp
  46 __exit:                 ! _exit(rv)
  47   mov   bx,sp
  48   mov   ax,[bx+2]
  49   mov   ah,#$4c
  50   int   #$21
  51 dos_1_exit:
  52   int   #$20
  53
  54   .text
  55 export ___cstartup      ! Crt0 startup
  56 ___cstartup:
  57   mov   ax,#$3000       ! Get DOS version
  58   int   $21
  59   cmp   al,#2           ! DOS 2+ is Ok
  60   jb    dos_1_exit
  61
  62   mov   dx,cs           ! Current CS
  63   add   dx,#__segoff    ! This var generated by the linker
  64   mov   ds,dx           ! Correct DS
  65
  66   mov   [___psp],es     ! PSP segment
  67   seg   es
  68   mov   ax,[$2c]
  69   mov   [___envseg],ax  ! Enviroment Segment
  70
  71                         ! Now need to free some RAM
  72   seg   es
  73   mov   bx,[2]          ! Top of Ram
  74   mov   ax,ds
  75   add   ax,#4096        ! Top of 64k data seg
  76   jc    use_tor         ! Oops, wrapped
  77   cmp   ax,bx
  78   jnc   use_tor         ! Bigger than tor
  79   mov   bx,ax
  80 use_tor:
  81   mov   ax,cs           ! Work out how big the memseg is needed
  82   sub   bx,ax
  83   mov   ah,#$4A         ! Set it
  84   int   $21
  85   jnc   set_stack       ! Good.
  86   ! Ooops, problem..
  87   ! BX is now how big it can be so set that.
  88   ! FIXME should check for BSS v Stack overlap
  89   mov   ah,#$4A
  90   int   $21
  91
  92 set_stack:              ! Now set SS to the same as DS
  93   sub   bx,#__segoff    ! And SP to the top of available memory.
  94   mov   cl,#4
  95   shl   bx,cl
  96   sub   bx,#2
  97   mov   ss,dx
  98   mov   sp,bx
  99
 100 zap_bss:                ! Clear the BSS
 101   mov   es,dx           ! ES now data seg
 102   mov   di,#__edata
 103   mov   cx,#__end
 104   sub   cx,di
 105   xor   ax,ax
 106   cld
 107   rep
 108    stosb
 109
 110   push  [_def_environ]  ! Defaults for when nothing is used.
 111   mov   ax,#_defarg
 112   push  ax
 113   mov   ax,#1
 114   push  ax
 115
 116   mov   si,#auto_start  ! Pointer to first autostart function
 117 auto_run:
 118   mov   bx,[si]
 119   test  bx,bx
 120   jz    no_entry
 121   call  bx              ! Call the function
 122 no_entry:
 123   inc   si              ! SI at next
 124   inc   si
 125   jmp   auto_run        ! And round for the next.
 126
 127 call_exit:              ! Last item called by above.
 128   pop   bx              ! Be tidy.
 129   push  ax              ! At the end the last called was main() push it`s
 130   call  _exit           ! return val and call exit();
 131 bad_exit:
 132   jmp   bad_exit        ! Exit returned !!
 133
 134   loc   2
 135   .word _main           ! Segment 2 is the trailing pointers, main and the
 136   .word call_exit       ! routine to call exit.
 137 data_start:
 138
 139   .text
 140
 141 #endasm
 142
 143 __E_nosys()
 144 {
 145 #asm
 146    .text
 147
 148 export sys_call5
 149 export sys_call4
 150 export sys_call3
 151 export sys_call2
 152 export sys_call1
 153 export sys_call0
 154 sys_call5:              ! Trap the unemulated Linux86 syscalls
 155 sys_call4:
 156 sys_call3:
 157 sys_call2:
 158 sys_call1:
 159 sys_call0:
 160
 161 #endasm
 162    errno = ENOSYS;
 163    return -1;
 164 }
 165 #endif
 166
 167 #ifdef L___mkargv
 168
 169 #ifdef __AS386_16__
 170 #asm
 171   loc   1               ! Make sure the pointer is in the correct segment
 172 auto_func:              ! Label for bcc -M to work.
 173   .word ___mkargv       ! Pointer to the autorun function
 174   .text                 ! So the function after is also in the correct seg.
 175 #endasm
 176 #endif
 177
 178 __mkargv(__argc, __argv)
 179 int __argc;
 180 char ** __argv;
 181 {
 182    int length, i, argc=1, s=0;
 183    unsigned char *ptr, *p;
 184    __set_es(__psp);                     /* Pointer to the args */
 185    length = __peek_es(0x80);            /* Length of cmd line */
 186    if( length > 0 )
 187    {
 188       ptr = (char*) sbrk(length+1);     /* Allocate some space */
 189
 190       for(i=0; i<length; i++)           /* Copy it in. */
 191       {
 192         ptr[i] = __peek_es(0x81+i);
 193         if( ptr[i] >  ' ' && s == 0 ) { argc++; s=1; }
 194         if( ptr[i] <= ' ' && s == 1 ) s=0;
 195       }
 196       ptr[length]=0;
 197
 198       p= __argv[0];
 199       __argv = (char**) sbrk((argc+1)*sizeof(char*));
 200       __argv[0] = p;            /* TODO: The real command can be found */
 201       __argc=argc;
 202
 203       /*
 204        * TODO: This needs to understand quoting and wildcards
 205        */
 206
 207       argc=1; s=0;
 208       for(i=0; i<length; i++)
 209       {
 210         if( ptr[i] >  ' ' && s == 0 ) { __argv[argc++] = ptr+i; s=1; }
 211         if( ptr[i] <= ' ' && s == 1 ) { ptr[i] = '\0'; s=0; }
 212       }
 213       __argv[argc] = 0;
 214    }
 215 }
 216 #endif
 217
 218 #ifdef L___mkenvp
 219
 220 #ifdef __AS386_16__
 221 #asm
 222   loc   1               ! Make sure the pointer is in the correct segment
 223 auto_func:              ! Label for bcc -M to work.
 224   .word ___mkenvp       ! Pointer to the autorun function
 225   .text                 ! So the function after is also in the correct seg.
 226 #endasm
 227 #endif
 228
 229 char ** environ = 0;
 230
 231 __mkenvp(__argc, __argv, __envp)
 232 int __argc;
 233 char ** __argv;
 234 char ** __envp;
 235 {
 236     /* FIXME !!!
 237      *
 238      * Note must write to __envp argument but not touch __argv or __argc
 239      */
 240 }
 241 #endif
 242
 243 #ifdef L_dos__fconv
 244 /* This function converts filenames from unix like to DOS. */
 245 char *
 246 __fconv(fname)
 247 char * fname;
 248 {
 249 static char buf1[66], buf2[66], *str = 0;
 250    register char *p, ch;
 251    int dot = 0;
 252
 253    if( strcmp("/dev/tty", fname) == 0 ) return "CON:";
 254
 255    if( str == buf1 ) str = buf2; else str = buf1;
 256
 257    p = str;
 258    if( strncmp("/mnt/", fname, 5) == 0 )
 259    {
 260       strcpy(p, "A:"); p+=2; fname+=4;
 261    }
 262    /*
 263     * POSS:
 264     * open("/name/*", ...); looks for an environ var PATH_name=c:\x\y\z
 265     */
 266
 267    while((ch = *fname++) && p < str+65)
 268    {
 269       if( ( ch >= 'a' && ch <= 'z' )
 270        || ( ch >= '0' && ch <= '9' )
 271        || ch == ':' || ch == '%' || ch == '-' || ch == '$' )
 272          ;
 273       else if( ch >= 'A' && ch <= 'Z' )
 274          ch = ch-'A'+'a';
 275       else if( ch == '.' && dot == 0 )
 276          dot = 1;
 277       else if( ch == '/' || ch == '\\' )
 278       {
 279          dot = 0; ch = '\\';
 280       }
 281       else ch = '_';
 282
 283       *p++ = ch;
 284    }
 285    *p++ = '\0';
 286    return str;
 287 }
 288 #endif
 289
 290 #ifdef L___exterror
 291
 292 static char errno_xlate[] = {
 293    0, EINVAL, ENOENT, ENOENT, EMFILE, EACCES, EBADF, EFAULT, ENOMEM,
 294    EFAULT, ENOMEM, EINVAL, EINVAL, EINVAL, EINVAL, ENODEV, EPERM, EXDEV,
 295    ENFILE, EROFS, ENODEV, ENXIO, EINVAL, EIO, EINVAL, ESPIPE, EIO, EIO,
 296    EAGAIN, EIO, EIO, EIO, EBUSY, EBUSY, ENODEV, EFAULT, ENOLCK, EFAULT,
 297    EFAULT, ENOSPC
 298 };
 299
 300 __exterror()
 301 {
 302 #asm
 303 export exterror
 304 exterror:
 305   push  ds
 306   push  es
 307   push  di
 308   push  si
 309   push  bp
 310   xor   bx,bx
 311   mov   ah,#$59
 312   int   $21
 313   pop   bp
 314   pop   si
 315   pop   di
 316   pop   es
 317   pop   ds
 318   mov   __doserrno,ax
 319 #endasm
 320   {
 321      int nerrno;
 322      extern unsigned _doserrno;
 323
 324      if( _doserrno == 0 )
 325         /* No error? No change. */;
 326      else if( _doserrno >= sizeof(errno_xlate)
 327            || errno_xlate[_doserrno] == EFAULT )
 328         errno = 16384+_doserrno;
 329      else
 330         errno = errno_xlate[_doserrno];
 331   }
 332   return -1;
 333 }
 334 #endif
 335
 336 #ifdef L_dos_read
 337 int
 338 read(fd, ptr, len)
 339 int fd;
 340 char *ptr;
 341 unsigned len;
 342 {
 343 #asm
 344   mov   bx,sp
 345   mov   cx,[bx+6]
 346   mov   dx,[bx+4]
 347   mov   bx,[bx+2]
 348   mov   ah,#$3f
 349   int   #$21
 350   jnc   readok
 351   br    exterror
 352 readok:
 353 #endasm
 354 }
 355 #endif
 356
 357 #ifdef L_dos_write
 358 int
 359 write(fd, ptr, len)
 360 int fd;
 361 char *ptr;
 362 unsigned len;
 363 {
 364 #asm
 365   mov   bx,sp
 366   mov   cx,[bx+6]
 367   mov   dx,[bx+4]
 368   mov   bx,[bx+2]
 369   mov   ah,#$40
 370   int   #$21
 371   jnc   writeok
 372   br    exterror
 373 writeok:
 374 #endasm
 375 }
 376 #endif
 377
 378 #ifdef L_dos_open
 379 int
 380 open(fname, type, cmode)
 381 char * fname;
 382 int type;
 383 int cmode;
 384 {
 385    register char * nname = __fconv(fname);
 386    int creat_mode = 0;
 387    int rv;
 388
 389 static int xlate_mode[] = {
 390 #ifdef OPEN_LIKE_UNIX
 391    O_RDONLY|O_DENYNONE,
 392    O_WRONLY|O_DENYNONE,
 393    O_RDWR|O_DENYNONE,
 394 #else
 395    O_RDONLY|O_DENYNONE,
 396    O_WRONLY|O_DENYWRITE,
 397    O_RDWR|O_DENYALL,
 398 #endif
 399    3
 400 };
 401
 402    if( (cmode & 0222) == 0 ) creat_mode = 1;
 403
 404    /* BzzzT. Assume these flags both mean the merge of them */
 405    /* BzzzT. Also ignore O_EXCL */
 406    if( type & (O_TRUNC|O_CREAT) )
 407       rv = __dos_creat(nname, creat_mode);
 408
 409    else
 410    {
 411       /* If we would open in compatibility mode make it a little more unixy */
 412       if( type & O_DENYMODE )
 413          rv = __dos_open(nname, type&(O_ACCMODE|O_DENYMODE|O_SETFD));
 414       else
 415          rv = __dos_open(nname, xlate_mode[type&O_ACCMODE]);
 416    }
 417    return rv;
 418 }
 419
 420 __dos_open(fname, mode)
 421 {
 422 #asm
 423   mov   bx,sp
 424   mov   dx,[bx+2]               ;ds:dx points to source string
 425   mov   al,[bx+4]               ;access code
 426   mov   ah,#$3d                 ;ask for a open
 427   int   #$21
 428   jnc   openok                  ;return handle if no error
 429   br    exterror
 430 openok:
 431 #endasm
 432 }
 433
 434 __dos_creat(fname)
 435 char * fname;
 436 {
 437 #asm
 438   mov     bx,sp
 439   mov     dx,[bx+2]               ;ds:dx points to source string
 440   xor     cx,cx                   ;normal attributes
 441   mov     ah,#$3c                 ;ask for a create
 442   int     #$21
 443   jnc     creok                   ;return handle if no error
 444   br    exterror
 445 creok:
 446 #endasm
 447 }
 448 #endif
 449
 450 #ifdef L_dos_close
 451 close(fd)
 452 {
 453 #asm
 454   mov     bx,sp
 455   mov     bx,[bx+2]           ;file handle
 456   mov     ah,#$3e             ;ask for a close
 457   int     #$21
 458   mov     ax,0                ;return 0 if no error
 459   jnc     closeok
 460   br    exterror
 461 closeok:
 462 #endasm
 463 }
 464 #endif
 465
 466 #ifdef L_dos_unlink
 467 unlink(fname)
 468 char * fname;
 469 {
 470 #asm
 471   mov   bx,sp
 472   push  [bx+2]
 473   call  ___fconv
 474   inc   sp
 475   inc   sp
 476   mov   dx,ax                   ;ds:dx points to source string
 477   mov   ah,#$41                 ;ask for a unlink
 478   int   #$21
 479   mov   ax,0                    ;assume no errors
 480   jnc   unlok
 481   br    exterror
 482 unlok:
 483 #endasm
 484 }
 485 #endif
 486
 487 #ifdef L_dos_lseek
 488 long
 489 lseek(fd, offset, mode)
 490 int fd, mode;
 491 long offset;
 492 {
 493 #asm
 494   mov     bx,sp
 495   mov     al,[bx+8]         ;mode of seek (0 to 2)
 496   mov     dx,[bx+4]         ;cx:dx is long offset
 497   mov     cx,[bx+6]
 498   mov     bx,[bx+2]         ;file handle
 499   mov     ah,#$42
 500   int     #$21              ;do the lseek
 501   jnc     seekok
 502   call    exterror
 503   mov     dx,ax
 504 seekok:
 505 #endasm
 506 }
 507 #endif
 508
 509 #ifdef L_dos_segalloc
 510 unsigned int
 511 __segalloc(paracount)
 512 unsigned int paracount;
 513 {
 514 #asm
 515   mov   bx,sp
 516   mov   bx,[bx+2]
 517   mov   ah,#$48
 518   int   $21
 519   jnc   ok
 520   mov   ax,#0
 521 ok:
 522 #endasm
 523 }
 524 #endif
 525
 526 #ifdef L_dos_segfree
 527 unsigned int
 528 __segfree(segno)
 529 unsigned int segno;
 530 {
 531 #asm
 532   push  es
 533   mov   bx,sp
 534   mov   es,[bx+4]
 535   mov   ah,#$49
 536   int   $21
 537   jc    err
 538   mov   ax,#0
 539 err:
 540   pop   es
 541 #endasm
 542 }
 543 #endif
 544
 545 #ifdef L_dos_setvect
 546 void
 547 __setvect(i,j)
 548 int i;
 549 long j;
 550 {
 551 #asm
 552   mov   bx,sp
 553   mov   ax,[bx+2]
 554   mov   dx,[bx+4]
 555   mov   bx,[bx+6]
 556   push  ds
 557   test  bx,bx
 558   jnz   got_seg
 559   mov   bx,cs
 560 got_seg:
 561   mov   ds,bx
 562   mov   ah,#$25
 563   int   $21
 564   pop   ds
 565 #endasm
 566 }
 567 #endif
 568
 569 #ifdef L_dos_getvect
 570 long
 571 __getvect(vecno)
 572 int vecno;
 573 {
 574 #asm
 575   mov   bx,sp
 576   mov   ax,[bx+2]
 577   mov   ah,#$35
 578   push  es
 579   int   #$21
 580   mov   dx,es
 581   mov   ax,bx
 582   pop   es
 583 #endasm
 584 }
 585 #endif
 586
 587 #ifdef L_dos_getmod
 588 int
 589 __dos_getmod(fname)
 590 {
 591 #asm
 592 #if __FIRST_ARG_IN_AX__
 593   mov   dx,ax
 594 #else
 595   mov   bx,sp
 596   mov   dx,[bx+2]
 597 #endif
 598   mov   ax,#$4300
 599   int   #$21
 600   jnc   statok
 601   br    exterror
 602 statok:
 603   mov   ax,cx
 604 #endasm
 605 }
 606 #endif
 607
 608 #ifdef L_dos_stat
 609 int
 610 __dos_stat(fname, dtaptr)
 611 {
 612 #asm
 613   mov   bx,sp
 614 #if __FIRST_ARG_IN_AX__
 615   mov   cx,ax
 616   mov   dx,[bx+2]
 617 #else
 618   mov   dx,[bx+4]
 619 #endif
 620   mov   ah,#$1A         ; Set DTA to requested
 621   int   #$21
 622 #if __FIRST_ARG_IN_AX__
 623   mov   ax,cx
 624 #else
 625   mov   dx,[bx+2]
 626 #endif
 627   mov   ax,#$4300       ; Locate the file
 628   int   #$21
 629   jc    nonesuch
 630   mov   ax,#$4e00       ; Get all the available information.
 631   int   #$21
 632   jc    nonesuch
 633   xor   ax,ax
 634   ret
 635 nonesuch:
 636   mov   ax,#2
 637   mov   _errno,ax
 638   mov   ax,#-1
 639 #endasm
 640 }
 641 #endif
 642
 643 #ifdef L_dos_isatty
 644 isatty(fd)
 645 int fd;
 646 {
 647 #asm
 648   mov   bx,sp
 649   mov   bx,[bx+2]
 650   mov   ah,#$44
 651   mov   al,#0
 652   int   #$21
 653   xor   ax,ax
 654   test  dx,#$80
 655   jz    not_tty
 656   inc   ax
 657 not_tty:
 658 #endasm
 659 }
 660 #endif
 661
 662 #ifdef L_dos_abort
 663 abort()
 664 {
 665    write(2, "Abnormal program termination\r\n", 30);
 666    _exit(3);
 667 }
 668 #endif
 669
 670 #ifdef L_bdos
 671 bdos(dosfn, dosdx, dosal)
 672 int dosfn;
 673 unsigned dosdx, dosal;
 674 {
 675 #asm
 676 _bdosptr = _bdos
 677   mov   bx,sp
 678   push  si
 679   push  di
 680
 681   mov   dx,_bdos.dosdx[bx]
 682   mov   cx,_bdos.dosfn[bx]
 683   mov   ax,_bdos.dosal[bx]
 684   mov   ah,cl
 685
 686   int   $21
 687
 688   pop   di
 689   pop   si
 690 #endasm
 691 }
 692 #endif
 693
 694 #endif /* __MSDOS__ */
 695 #endif /* __AS386_16__ */
 696 #endif /* !__FIRST_ARG_IN_AX__ */
 697
 698 /*
 699 # Name          No      Args    Flag, comment
 700 CHDIR           12      1
 701 TIME            13      1       * No long return val, arg _must_ exist.
 702 MKNOD           14      3
 703 CHMOD           15      2
 704 CHOWN           16      3
 705 BRK             17      1       * This is only to tell the system
 706 STAT            18      2
 707 GETPID          20      1       * This gets both pid & ppid
 708 MOUNT           21      3       * Need more args & no ELKS
 709 UMOUNT          22      1       . No ELKS
 710 SETUID          23      1
 711 GETUID          24      1       * This gets both uid and euid
 712 STIME           25      2       . No ELKS should be 1 LONG arg
 713 PTRACE          26      X       +
 714 ALARM           27      2       ?       No unused return.
 715 FSTAT           28      2
 716 PAUSE           29      0
 717 UTIME           30      2
 718 STTY            31      2       . ELKS ain't got this and it'll probably change
 719 GTTY            32      2       . ELKS ain't got this and it'll probably change
 720 ACCESS          33      2
 721 NICE            34      1
 722 FTIME           35      1       . ELKS ain't got this.
 723 SYNC            36      0
 724 KILL            37      2
 725 RENAME          38      2
 726 MKDIR           39      2
 727 RMDIR           40      1
 728 DUP             41      X       - Using nasty fcntl function
 729 PIPE            42      1
 730 TIMES           43      1
 731 PROF            44      X       +
 732 SETGID          46      1
 733 GETGID          47      1       * This gets both gid and egid
 734 SIGNAL          48      2       +
 735 ACCT            51      X       +
 736 PLOCK           53      X       +
 737 IOCTL           54      3
 738 FCNTL           55      3
 739 EXEC            59      2       ?
 740 UMASK           60      1
 741 CHROOT          61      1
 742 SIGACTION       71      X
 743 SIGSUSPEND      72      X
 744 SIGPENDING      73      X
 745 SIGPROCMASK     74      X
 746 SIGRETURN       75      X
 747 REBOOT          76      3       . No ELKS and the magic number will be diff.
 748 */
 749