windows-nt/Source/XPSP1/NT/base/crts/fpw32/conv/cfin.c
2020-09-26 16:20:57 +08:00

75 lines
1.9 KiB
C

/***
*cfin.c - Encode interface for C
*
* Copyright (c) 1991-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
*
*Revision History:
* 07-20-91 GDP Ported to C from assembly
* 04-30-92 GDP use __strgtold12 and _ld12tod
* 06-22-92 GDP use new __strgtold12 interface
* 04-06-93 SKS Replace _CALLTYPE* with __cdecl
* 09-06-94 CFW Replace MTHREAD with _MT.
* 10-06-99 PML Copy a DOUBLE, not double, to avoid exceptions
*
*******************************************************************************/
#include <string.h>
#include <cv.h>
#ifndef _MT
static struct _flt ret;
static FLT flt = &ret;
#endif
/* The only three conditions that this routine detects */
#define CFIN_NODIGITS 512
#define CFIN_OVERFLOW 128
#define CFIN_UNDERFLOW 256
/* This version ignores the last two arguments (radix and scale)
* Input string should be null terminated
* len is also ignored
*/
#ifdef _MT
FLT __cdecl _fltin2(FLT flt, const char *str, int len_ignore, int scale_ignore, int radix_ignore)
#else
FLT __cdecl _fltin(const char *str, int len_ignore, int scale_ignore, int radix_ignore)
#endif
{
_LDBL12 ld12;
DOUBLE x;
const char *EndPtr;
unsigned flags;
int retflags = 0;
flags = __strgtold12(&ld12, &EndPtr, str, 0, 0, 0, 0);
if (flags & SLD_NODIGITS) {
retflags |= CFIN_NODIGITS;
*(u_long *)&x = 0;
*((u_long *)&x+1) = 0;
}
else {
INTRNCVT_STATUS intrncvt;
intrncvt = _ld12tod(&ld12, &x);
if (flags & SLD_OVERFLOW ||
intrncvt == INTRNCVT_OVERFLOW) {
retflags |= CFIN_OVERFLOW;
}
if (flags & SLD_UNDERFLOW ||
intrncvt == INTRNCVT_UNDERFLOW) {
retflags |= CFIN_UNDERFLOW;
}
}
flt->flags = retflags;
flt->nbytes = (int)(EndPtr - str);
*(DOUBLE *)&flt->dval = *(DOUBLE *)&x;
return flt;
}