Function decShowNum

extern/decNumber/decCommon.c:1788–1838

---------------------------------------------------------------- */ decShowNum -- display bcd8 number in debug form */ / num is the bcdnum to display */ tag is a string to label the display */ ---------------------------------------------------------------- */

  /*   tag is a string to label the display                           */
  /* ---------------------------------------------------------------- */
  void decShowNum(const bcdnum *num, const char *tag) {
    const char *csign="+";              // sign character
    uByte *ub;                          // work
    uInt  uiwork;                       // for macros
    if (num->sign==DECFLOAT_Sign) csign="-";

    printf(">%s> ", tag);
    if (num->exponent==DECFLOAT_Inf) printf("%sInfinity", csign);
    else if (num->exponent==DECFLOAT_qNaN) printf("%sqNaN", csign);
    else if (num->exponent==DECFLOAT_sNaN) printf("%ssNaN", csign);
    else {                              // finite
     char qbuf[10];                     // for right-aligned q
     char *c;                           // work
     const uByte *u;                    // ..
     Int e=num->exponent;               // .. exponent
     strcpy(qbuf, "q=");
     c=&qbuf[2];                        // where exponent will go
     // lay out the exponent
     if (e<0) {
       *c++='-';                        // add '-'
       e=-e;                            // uInt, please
       }
     #if DECEMAXD>4
       #error Exponent form is too long for ShowNum to lay out
     #endif
     if (e==0) *c++='0';                // 0-length case
      else if (e<1000) {                // 3 (or fewer) digits case
       u=&BIN2BCD8[e*4];                // -> 3 digits + length byte
       UBFROMUI(c, UBTOUI(u+3-*(u+3))|CHARMASK); // [as above]
       c+=*(u+3);                       // bump pointer appropriately
       }
      else {                            // 4-digits
       Int thou=((e>>3)*1049)>>17;      // e/1000
       Int rem=e-(1000*thou);           // e%1000
       *c++=(char)('0'+(char)thou);     // the thousands digit
       u=&BIN2BCD8[rem*4];              // -> 3 digits + length byte
       UBFROMUI(c, UBTOUI(u)|CHARMASK); // copy fixed 3+1 characters [is safe]
       c+=3;                            // bump pointer, always 3 digits
       }
     *c='\0';                           // add terminator
     printf("%7s c=%s", qbuf, csign);
     }

    if (!EXPISSPECIAL(num->exponent) || num->msd!=num->lsd || *num->lsd!=0) {
      for (ub=num->msd; ub<=num->lsd; ub++) { // coefficient...
        printf("%1x", *ub);
        if ((num->lsd-ub)%3==0 && ub!=num->lsd) printf(" "); // 4-space
        }
      }
    printf("\n");
    } // decShowNum
#endif