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Diffstat (limited to 'misc/efgcvt_r.c')
-rw-r--r--misc/efgcvt_r.c94
1 files changed, 71 insertions, 23 deletions
diff --git a/misc/efgcvt_r.c b/misc/efgcvt_r.c
index e6030c8543..69caef01d7 100644
--- a/misc/efgcvt_r.c
+++ b/misc/efgcvt_r.c
@@ -37,6 +37,7 @@
#define FLOOR APPEND(floor, FLOAT_NAME_EXT)
#define FABS APPEND(fabs, FLOAT_NAME_EXT)
#define LOG10 APPEND(log10, FLOAT_NAME_EXT)
+#define EXP APPEND(exp, FLOAT_NAME_EXT)
int
@@ -54,9 +55,12 @@ APPEND (FUNC_PREFIX, fcvt_r) (value, ndigit, decpt, sign, buf, len)
return -1;
}
- *sign = value < 0.0;
- if (*sign)
- value = - value;
+ if (isfinite (value))
+ {
+ *sign = signbit (value) != 0;
+ if (*sign)
+ value = -value;
+ }
n = snprintf (buf, len, "%.*" FLOAT_FMT_FLAG "f", ndigit, value);
if (n < 0)
@@ -66,16 +70,29 @@ APPEND (FUNC_PREFIX, fcvt_r) (value, ndigit, decpt, sign, buf, len)
while (i < n && isdigit (buf[i]))
++i;
*decpt = i;
- do
- ++i;
- while (! isdigit (buf[i]));
- memmove (&buf[i - *decpt], buf, n - (i - *decpt));
+
+ if (i == 0)
+ {
+ /* Value is Inf or NaN. */
+ *sign = 0;
+ return 0;
+ }
+
+ if (i < n)
+ {
+ do
+ ++i;
+ while (i < n && !isdigit (buf[i]));
+ memmove (&buf[*decpt], &buf[i], n - i);
+ buf[n - (i - *decpt)] = 0;
+ }
return 0;
}
#define weak_extern2(name) weak_extern (name)
weak_extern2 (FLOOR) weak_extern2 (LOG10) weak_extern2 (FABS)
+weak_extern2 (EXP)
int
APPEND (FUNC_PREFIX, ecvt_r) (value, ndigit, decpt, sign, buf, len)
@@ -84,24 +101,55 @@ APPEND (FUNC_PREFIX, ecvt_r) (value, ndigit, decpt, sign, buf, len)
char *buf;
size_t len;
{
- FLOAT_TYPE (*log10_function) (FLOAT_TYPE) = &LOG10;
+ int exponent = 0;
- if (log10_function)
- {
- /* Use the reasonable code if -lm is included. */
- ndigit -= (int) FLOOR (LOG10 (FABS (value)));
- if (ndigit < 0)
- ndigit = 0;
- }
- else
+ if (isfinite (value) && value != 0.0)
{
- /* Slow code that doesn't require -lm functions. */
- FLOAT_TYPE d;
- for (d = value < 0.0 ? - value : value;
- ndigit > 0 && d >= 10.0;
- d *= 0.1)
- --ndigit;
+ FLOAT_TYPE (*log10_function) (FLOAT_TYPE) = &LOG10;
+
+ if (log10_function)
+ {
+ /* Use the reasonable code if -lm is included. */
+ FLOAT_TYPE dexponent;
+ dexponent = FLOOR (LOG10 (FABS (value)));
+ value *= EXP (dexponent * -M_LN10);
+ exponent = (int) dexponent;
+ }
+ else
+ {
+ /* Slow code that doesn't require -lm functions. */
+ FLOAT_TYPE d;
+ if (value < 0.0)
+ d = -value;
+ else
+ d = value;
+ if (d < 1.0)
+ {
+ do
+ {
+ d *= 10.0;
+ exponent--;
+ }
+ while (d < 1.0);
+ }
+ else if (d >= 10.0)
+ {
+ do
+ {
+ d *= 0.1;
+ exponent++;
+ }
+ while (d >= 10.0);
+ }
+ if (value < 0.0)
+ value = -d;
+ else
+ value = d;
+ }
}
- return APPEND (FUNC_PREFIX, fcvt_r) (value, ndigit, decpt, sign, buf, len);
+ if (APPEND (FUNC_PREFIX, fcvt_r) (value, ndigit - 1, decpt, sign, buf, len))
+ return -1;
+ *decpt += exponent;
+ return 0;
}