-/* Copyright (C) 1991, 1992, 1997, 1999, 2003, 2006 Free Software Foundation, Inc.
+/* Copyright (C) 1991-1992, 1997, 1999, 2003, 2006, 2008-2010 Free Software
+ Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include <config.h>
-#include <errno.h>
-
-#include <ctype.h>
+/* Don't use __attribute__ __nonnull__ in this compilation unit. Otherwise gcc
+ optimizes away the nptr == NULL test below. */
+#define _GL_ARG_NONNULL(params)
-#include <math.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <errno.h>
#include <float.h>
-#include <stdlib.h>
+#include <math.h>
+#include <stdbool.h>
#include <string.h>
+#include "c-ctype.h"
+
/* Convert NPTR to a double. If ENDPTR is not NULL, a pointer to the
character after the last one used in the number is put in *ENDPTR. */
double
strtod (const char *nptr, char **endptr)
{
- register const char *s;
- short int sign;
+ const unsigned char *s;
+ bool negative = false;
/* The number so far. */
double num;
- int got_dot; /* Found a decimal point. */
- int got_digit; /* Seen any digits. */
+ bool got_dot; /* Found a decimal point. */
+ bool got_digit; /* Seen any digits. */
+ bool hex = false; /* Look for hex float exponent. */
/* The exponent of the number. */
long int exponent;
goto noconv;
}
- s = nptr;
+ /* Use unsigned char for the ctype routines. */
+ s = (unsigned char *) nptr;
/* Eat whitespace. */
- while (isspace ((unsigned char) *s))
+ while (isspace (*s))
++s;
/* Get the sign. */
- sign = *s == '-' ? -1 : 1;
+ negative = *s == '-';
if (*s == '-' || *s == '+')
++s;
num = 0.0;
- got_dot = 0;
- got_digit = 0;
+ got_dot = false;
+ got_digit = false;
exponent = 0;
- for (;; ++s)
+
+ /* Check for hex float. */
+ if (*s == '0' && c_tolower (s[1]) == 'x'
+ && (c_isxdigit (s[2]) || ('.' == s[2] && c_isxdigit (s[3]))))
{
- if ('0' <= *s && *s <= '9')
- {
- got_digit = 1;
-
- /* Make sure that multiplication by 10 will not overflow. */
- if (num > DBL_MAX * 0.1)
- /* The value of the digit doesn't matter, since we have already
- gotten as many digits as can be represented in a `double'.
- This doesn't necessarily mean the result will overflow.
- The exponent may reduce it to within range.
-
- We just need to record that there was another
- digit so that we can multiply by 10 later. */
- ++exponent;
- else
- num = (num * 10.0) + (*s - '0');
-
- /* Keep track of the number of digits after the decimal point.
- If we just divided by 10 here, we would lose precision. */
- if (got_dot)
- --exponent;
- }
- else if (!got_dot && *s == '.')
- /* Record that we have found the decimal point. */
- got_dot = 1;
- else
- /* Any other character terminates the number. */
- break;
+ hex = true;
+ s += 2;
+ for (;; ++s)
+ {
+ if (c_isxdigit (*s))
+ {
+ got_digit = true;
+
+ /* Make sure that multiplication by 16 will not overflow. */
+ if (num > DBL_MAX / 16)
+ /* The value of the digit doesn't matter, since we have already
+ gotten as many digits as can be represented in a `double'.
+ This doesn't necessarily mean the result will overflow.
+ The exponent may reduce it to within range.
+
+ We just need to record that there was another
+ digit so that we can multiply by 16 later. */
+ ++exponent;
+ else
+ num = ((num * 16.0)
+ + (c_tolower (*s) - (c_isdigit (*s) ? '0' : 'a' - 10)));
+
+ /* Keep track of the number of digits after the decimal point.
+ If we just divided by 16 here, we would lose precision. */
+ if (got_dot)
+ --exponent;
+ }
+ else if (!got_dot && *s == '.')
+ /* Record that we have found the decimal point. */
+ got_dot = true;
+ else
+ /* Any other character terminates the number. */
+ break;
+ }
+ }
+
+ /* Not a hex float. */
+ else
+ {
+ for (;; ++s)
+ {
+ if (c_isdigit (*s))
+ {
+ got_digit = true;
+
+ /* Make sure that multiplication by 10 will not overflow. */
+ if (num > DBL_MAX * 0.1)
+ /* The value of the digit doesn't matter, since we have already
+ gotten as many digits as can be represented in a `double'.
+ This doesn't necessarily mean the result will overflow.
+ The exponent may reduce it to within range.
+
+ We just need to record that there was another
+ digit so that we can multiply by 10 later. */
+ ++exponent;
+ else
+ num = (num * 10.0) + (*s - '0');
+
+ /* Keep track of the number of digits after the decimal point.
+ If we just divided by 10 here, we would lose precision. */
+ if (got_dot)
+ --exponent;
+ }
+ else if (!got_dot && *s == '.')
+ /* Record that we have found the decimal point. */
+ got_dot = true;
+ else
+ /* Any other character terminates the number. */
+ break;
+ }
}
if (!got_digit)
- goto noconv;
+ {
+ /* Check for infinities and NaNs. */
+ if (c_tolower (*s) == 'i'
+ && c_tolower (s[1]) == 'n'
+ && c_tolower (s[2]) == 'f')
+ {
+ s += 3;
+ num = HUGE_VAL;
+ if (c_tolower (*s) == 'i'
+ && c_tolower (s[1]) == 'n'
+ && c_tolower (s[2]) == 'i'
+ && c_tolower (s[3]) == 't'
+ && c_tolower (s[4]) == 'y')
+ s += 5;
+ goto valid;
+ }
+#ifdef NAN
+ else if (c_tolower (*s) == 'n'
+ && c_tolower (s[1]) == 'a'
+ && c_tolower (s[2]) == 'n')
+ {
+ s += 3;
+ num = NAN;
+ /* Since nan(<n-char-sequence>) is implementation-defined,
+ we define it by ignoring <n-char-sequence>. A nicer
+ implementation would populate the bits of the NaN
+ according to interpreting n-char-sequence as a
+ hexadecimal number, but the result is still a NaN. */
+ if (*s == '(')
+ {
+ const unsigned char *p = s + 1;
+ while (c_isalnum (*p))
+ p++;
+ if (*p == ')')
+ s = p + 1;
+ }
+ goto valid;
+ }
+#endif
+ goto noconv;
+ }
- if (tolower ((unsigned char) *s) == 'e')
+ if (c_tolower (*s) == (hex ? 'p' : 'e') && !isspace (s[1]))
{
/* Get the exponent specified after the `e' or `E'. */
int save = errno;
char *end;
- long int exp;
+ long int value;
errno = 0;
++s;
- exp = strtol (s, &end, 10);
- if (errno == ERANGE)
- {
- /* The exponent overflowed a `long int'. It is probably a safe
- assumption that an exponent that cannot be represented by
- a `long int' exceeds the limits of a `double'. */
- if (endptr != NULL)
- *endptr = end;
- if (exp < 0)
- goto underflow;
- else
- goto overflow;
- }
- else if (end == s)
- /* There was no exponent. Reset END to point to
- the 'e' or 'E', so *ENDPTR will be set there. */
- end = (char *) s - 1;
+ value = strtol ((char *) s, &end, 10);
+ if (errno == ERANGE && num)
+ {
+ /* The exponent overflowed a `long int'. It is probably a safe
+ assumption that an exponent that cannot be represented by
+ a `long int' exceeds the limits of a `double'. */
+ if (endptr != NULL)
+ *endptr = end;
+ if (value < 0)
+ goto underflow;
+ else
+ goto overflow;
+ }
+ else if (end == (char *) s)
+ /* There was no exponent. Reset END to point to
+ the 'e' or 'E', so *ENDPTR will be set there. */
+ end = (char *) s - 1;
errno = save;
- s = end;
- exponent += exp;
+ s = (unsigned char *) end;
+ exponent += value;
}
- if (endptr != NULL)
- *endptr = (char *) s;
-
if (num == 0.0)
- return 0.0;
+ goto valid;
+
+ if (hex)
+ {
+ /* ldexp takes care of range errors. */
+ num = ldexp (num, exponent);
+ goto valid;
+ }
/* Multiply NUM by 10 to the EXPONENT power,
checking for overflow and underflow. */
if (exponent < 0)
{
if (num < DBL_MIN * pow (10.0, (double) -exponent))
- goto underflow;
+ goto underflow;
}
else if (exponent > 0)
{
if (num > DBL_MAX * pow (10.0, (double) -exponent))
- goto overflow;
+ goto overflow;
}
num *= pow (10.0, (double) exponent);
- return num * sign;
+ valid:
+ if (endptr != NULL)
+ *endptr = (char *) s;
+ return negative ? -num : num;
-overflow:
+ overflow:
/* Return an overflow error. */
+ if (endptr != NULL)
+ *endptr = (char *) s;
errno = ERANGE;
- return HUGE_VAL * sign;
+ return negative ? -HUGE_VAL : HUGE_VAL;
-underflow:
+ underflow:
/* Return an underflow error. */
if (endptr != NULL)
- *endptr = (char *) nptr;
+ *endptr = (char *) s;
errno = ERANGE;
- return 0.0;
+ return negative ? -0.0 : 0.0;
-noconv:
+ noconv:
/* There was no number. */
if (endptr != NULL)
*endptr = (char *) nptr;
+ errno = EINVAL;
return 0.0;
}
projects / gnulib.git / blobdiff