v4.0/src/CMD/FDISK/DOS.H

   1 /* dos.h
   2  *
   3  * Defines the structs and unions used to handle the input and output
   4  * registers for the DOS interface routines defined in the V2.0 to V3.0
   5  * compatability package.  It also includes macros to access the segment
   6  * and offset values of MS C "far" pointers, so that they may be used by
   7  * these routines.
   8  *
   9  */
  10
  11 /* word registers */
  12
  13 struct WORDREGS {
  14         unsigned ax;
  15         unsigned bx;
  16         unsigned cx;
  17         unsigned dx;
  18         unsigned si;
  19         unsigned di;
  20         unsigned cflag;
  21         };
  22
  23 /* byte registers */
  24
  25 struct BYTEREGS {
  26         unsigned char al, ah;
  27         unsigned char bl, bh;
  28         unsigned char cl, ch;
  29         unsigned char dl, dh;
  30         };
  31
  32 /* general purpose registers union - overlays the corresponding word and
  33  * byte registers.
  34  */
  35
  36 union REGS {
  37         struct WORDREGS x;
  38         struct BYTEREGS h;
  39         };
  40
  41 /* segment registers */
  42
  43 struct SREGS {
  44         unsigned es;
  45         unsigned cs;
  46         unsigned ss;
  47         unsigned ds;
  48         };
  49
  50 /* dosexterror struct */
  51
  52 struct DOSERROR {
  53         int exterror;
  54         char class;
  55         char action;
  56         char locus;
  57         };
  58
  59 /* macros to break MS C "far" pointers into their segment and offset
  60  * components
  61  */
  62
  63 #define FP_SEG(fp) (*((unsigned *)&(fp) + 1))
  64 #define FP_OFF(fp) (*((unsigned *)&(fp)))
  65
  66 /* function declarations for those who want strong type checking
  67  * on arguments to library function calls
  68  */
  69
  70 #ifdef LINT_ARGS                /* arg. checking enabled */
  71
  72 int bdos(int, unsigned int, unsigned int);
  73 int dosexterr(struct DOSERROR *);
  74 int intdos(union REGS *, union REGS *);
  75 int intdosx(union REGS *, union REGS *, struct SREGS *);
  76 int int86(int, union REGS *, union REGS *);
  77 int int86x(int, union REGS *, union REGS *, struct SREGS *);
  78 void segread(struct SREGS *);
  79
  80 #endif  /* LINT_ARGS */
  81 \1a