pike.git/ src/ operators.c

2009-08-05

2009-08-05 09:43:19 by Martin Stjernholm <mast@lysator.liu.se>

• 9c040927e9750eddac027642ff9161cad971b55a (14 lines) (+7/-7) ^{[ Show | Annotate ]}
  Branch: 7.9

Use a decimal mantissa size that doesn't show rounding errors when
floats are cast to strings.

Rev: src/operators.c:1.251

2:   || This file is part of Pike. For copyright information see COPYRIGHT.   || Pike is distributed under GPL, LGPL and MPL. See the file COPYING   || for more information. - || $Id: operators.c,v 1.250 2009/07/12 19:43:05 grubba Exp $ + || $Id: operators.c,v 1.251 2009/08/05 09:43:19 mast Exp $   */      #include "global.h"
53:       /* One extra char for the sign. */   #define MAX_INT_SPRINTF_LEN (1 + (SIZEOF_INT_TYPE * 5 + 1) / 2) -  /* Three quarters of the float is the mantissa. */ - #define MAX_FLOAT_PREC_LEN ((SIZEOF_FLOAT_TYPE * 15 + 4) / 8) +     /* One quarter of the float is the exponent. */   #define MAX_FLOAT_EXP_LEN ((SIZEOF_FLOAT_TYPE * 5 + 4) / 8)    /* Six extra chars: Mantissa sign, decimal point, zero before the -  * decimal point, the 'e', exponent sign, and an extra digit due +  * decimal point, the 'e' exponent sign, and an extra digit due    * to the mantissa/exponent split. */ - #define MAX_FLOAT_SPRINTF_LEN (6 + MAX_FLOAT_PREC_LEN + MAX_FLOAT_EXP_LEN) + #define MAX_FLOAT_SPRINTF_LEN (6 + PIKEFLOAT_DIG + MAX_FLOAT_EXP_LEN)       /* Enough to hold a Pike float or int in textform including a trailing \0    */
486:       case T_FLOAT:    sprintf(buf,"%.*"PRINTPIKEFLOAT"g", -  MAX_FLOAT_PREC_LEN, sp[-1].u.float_number); +  PIKEFLOAT_DIG, sp[-1].u.float_number);    /* Ensure that either an exponent or a decimal point gets printed,    * since %g can remove both which would make it look like an integer. */    if (!strchr (buf, '.') && !strchr (buf, 'e'))
1628:       case T_FLOAT:    sprintf(buffer,"%.*"PRINTPIKEFLOAT"g", -  MAX_FLOAT_PREC_LEN, sp[e].u.float_number); +  PIKEFLOAT_DIG, sp[e].u.float_number);    /* See comment for T_FLOAT in o_cast_to_string. */    if (!strchr (buffer, '.') && !strchr (buffer, 'e'))    strcat (buffer, ".0");