Function decFloatNextPlus

extern/decNumber/decBasic.c:2735–2766

------------------------------------------------------------------ */ decFloatNextPlus -- next towards +Infinity */ / result gets the next larger decFloat */ dfl is the decFloat to start with */ set is the context */ returns result

/* an sNaN).                                                          */
/* ------------------------------------------------------------------ */
decFloat * decFloatNextPlus(decFloat *result, const decFloat *dfl,
                            decContext *set) {
  uInt savestat;                        // saves status
  enum rounding saveround;              // .. and mode
  decFloat delta;                       // tiny increment

  // -Infinity is the special case
  if (DFISINF(dfl) && DFISSIGNED(dfl)) {
    DFSETNMAX(result);
    DFWORD(result, 0)|=DECFLOAT_Sign;   // make negative
    return result;                      // [no status to set]
    }
  // other cases are effected by sutracting a tiny delta -- this
  // should be done in a wider format as the delta is unrepresentable
  // here (but can be done with normal add if the sign of zero is
  // treated carefully, because no Inexactitude is interesting);
  // rounding to +Infinity then pushes the result to next above
  decFloatZero(&delta);                 // set up tiny delta
  DFWORD(&delta, DECWORDS-1)=1;         // coefficient=1
  DFWORD(&delta, 0)=0;                  // Sign=0 + biased exponent=0
  // set up for the directional round
  saveround=set->round;                 // save mode
  set->round=DEC_ROUND_CEILING;         // .. round towards +Infinity
  savestat=set->status;                 // save status
  decFloatAdd(result, dfl, &delta, set);
  // Add rules mess up the sign when going from -Ntiny to -0
  if (DFISZERO(result)) DFWORD(result, 0)^=DECFLOAT_Sign; // correct
  set->status&=DEC_Invalid_operation;   // preserve only sNaN status
  set->status|=savestat;                // restore pending flags
  set->round=saveround;                 // .. and mode
  return result;
  } // decFloatNextPlus

/* ------------------------------------------------------------------ */
/* decFloatNextToward -- next towards a decFloat                      */