4.3BSD - /usr/src/new/icon/rt/cvstr.c

   1: #include "../h/rt.h"
   2: 
   3: /*
   4:  * cvstr(d,s) - convert d (in place) into a string, using s as buffer
   5:  *  if necessary.  cvstr returns 0 if the conversion fails, 1 if d
   6:  *  wasn't a string but was converted into one, and 2 if d was already
   7:  *  a string.  When a string conversion takes place, sbuf gets the
   8:  *  resulting string.
   9:  */
  10: 
  11: cvstr(d, sbuf)
  12: register struct descrip *d;
  13: char *sbuf;
  14:    {
  15: 
  16:    /*
  17:     * Dereference d if necessary.
  18:     */
  19:       DeRef(*d)
  20: 
  21:    if (QUAL(*d)) {
  22:       /*
  23:        * d is already a string.
  24:        */
  25:       if (NULLDESC(*d))
  26:          return (NULL);
  27:       return (2);
  28:       }
  29: 
  30:    switch (TYPE(*d)) {
  31:       /*
  32:        * For types that can be converted into strings, call the appropriate
  33:        *  conversion routine and return their result.  Note that the
  34:        *  conversion routines write over d.
  35:        */
  36:       case T_INTEGER:
  37:          return (itos((long)INTVAL(*d), d, sbuf));
  38: 
  39: #ifdef LONGS
  40:       case T_LONGINT:
  41:          return (itos(BLKLOC(*d)->longint.intval, d, sbuf));
  42: #endif LONGS
  43:       case T_REAL:
  44:          return (rtos(BLKLOC(*d)->realblk.realval, d, sbuf));
  45: 
  46:       case T_CSET:
  47:          return (cstos(BLKLOC(*d)->cset.bits, d, sbuf));
  48: 
  49:       default:
  50:          /*
  51:           * d can't be converted to a string.
  52:           */
  53:          return (NULL);
  54:       }
  55:    }
  56: 
  57: /*
  58:  * itos - convert the integer num into a string using s as a buffer and
  59:  *  making q a descriptor for the resulting string.
  60:  */
  61: static itos(num, q, s)
  62: long num;
  63: struct descrip *q;
  64: char *s;
  65:    {
  66:    register char *p;
  67:    long ival;
  68: 
  69:    p = s + MAXSTRING - 1;
  70:    ival = num;
  71: 
  72:    *p = '\0';
  73:    if (num >= 0L)
  74:       do {
  75:          *--p = ival % 10L + '0';
  76:          ival /= 10L;
  77:          } while (ival != 0L);
  78:    else {
  79:       do {
  80:          *--p = '0' - (ival % 10L);
  81:          ival /= 10L;
  82:          } while (ival != 0L);
  83:       *--p = '-';
  84:       }
  85: 
  86:    STRLEN(*q) = s + MAXSTRING - 1 - p;
  87:    STRLOC(*q) = p;
  88:    return (1);
  89:    }
  90: 
  91: /*
  92:  * rtos - convert the real number n into a string using s as a buffer and
  93:  *  making q a descriptor for the resulting string.
  94:  */
  95: rtos(n, q, s)
  96: double n;
  97: struct descrip *q;
  98: char *s;
  99:    {
 100:    /*
 101:     * gcvt does all the work.
 102:     */
 103:    gcvt(n, 8, s);
 104:    STRLEN(*q) = strlen(s);
 105:    STRLOC(*q) = s;
 106:    return (1);
 107:    }
 108: 
 109: /*
 110:  * cstos - convert the cset bit array pointed at by cs into a string using
 111:  *  s as a buffer and making q a descriptor for the resulting string.
 112:  */
 113: static cstos(cs, q, s)
 114: int *cs;
 115: struct descrip *q;
 116: char *s;
 117:    {
 118:    register char *p;
 119:    register int i;
 120: 
 121:    p = s;
 122:    for (i = 0; i < CSETSIZE*INTSIZE; i++) {
 123:       if (tstb(i, cs))
 124:          *p++ = (char)i;
 125:       }
 126:    *p = '\0';
 127: 
 128:    STRLEN(*q) = p - s;
 129:    STRLOC(*q) = s;
 130:    return (1);
 131:    }

Defined functions