+++ /dev/null
-/* atof.c: converts an ASCII string to float
-
- Copyright (C) 2003 Jesus Calvino-Fraga, jesusc@ieee.org
-
- This library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- This library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with this library; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
-
-#include <stdlib.h>
-#include <ctype.h>
-
-float atof(const char * s)
-{
- float value, fraction;
- char iexp;
- char sign;
-
- //Skip leading blanks
- while (isspace(*s)) s++;
-
- //Get the sign
- if (*s == '-')
- {
- sign=1;
- s++;
- }
- else
- {
- sign=0;
- if (*s == '+') s++;
- }
-
- //Get the integer part
- for (value=0.0f; isdigit(*s); s++)
- {
- value=10.0f*value+(*s-'0');
- }
-
- //Get the fraction
- if (*s == '.')
- {
- s++;
- for (fraction=0.1f; isdigit(*s); s++)
- {
- value+=(*s-'0')*fraction;
- fraction*=0.1f;
- }
- }
-
- //Finally, the exponent (not very efficient, but enough for now)
- if (toupper(*s)=='E')
- {
- s++;
- iexp=(char)atoi(s);
- {
- while(iexp!=0)
- {
- if(iexp<0)
- {
- value*=0.1f;
- iexp++;
- }
- else
- {
- value*=10.0f;
- iexp--;
- }
- }
- }
- }
-
- if(sign) value*=-1.0f;
- return (value);
-}
--- /dev/null
+/****************************************************************************
+ * lib/string/lib_strtod.c
+ * Convert string to double
+ *
+ * Copyright (C) 2002 Michael Ringgaard. All rights reserved.
+ * Copyright (C) 2006-2007 H. Peter Anvin.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <stdlib.h>
+#include <ctype.h>
+#include <errno.h>
+
+/****************************************************************************
+ * Pre-processor definitions
+ ****************************************************************************/
+
+/* These are predefined with GCC, but could be issues for other compilers. If
+ * not defined, an arbitrary big number is put in for now. These should be
+ * added to nuttx/compiler for your compiler.
+ */
+
+#if !defined(__DBL_MIN_EXP__) || !defined(__DBL_MAX_EXP__)
+# ifdef CONFIG_CPP_HAVE_WARNING
+# warning "Size of exponent is unknown"
+# endif
+# undef __DBL_MIN_EXP__
+# define __DBL_MIN_EXP__ (-1021)
+# undef __DBL_MAX_EXP__
+# define __DBL_MAX_EXP__ (1024)
+#endif
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+static inline int is_real(double x)
+{
+ const double infinite = 1.0/0.0;
+ return (x < infinite) && (x >= -infinite);
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/***************************************************(************************
+ * Name: strtod
+ *
+ * Description:
+ * Convert a string to a double value
+ *
+ ****************************************************************************/
+
+double strtod(const char *str, char **endptr)
+{
+ double number;
+ int exponent;
+ int negative;
+ char *p = (char *) str;
+ double p10;
+ int n;
+ int num_digits;
+ int num_decimals;
+ const double infinite = 1.0/0.0;
+
+ /* Skip leading whitespace */
+
+ while (isspace(*p))
+ {
+ p++;
+ }
+
+ /* Handle optional sign */
+
+ negative = 0;
+ switch (*p)
+ {
+ case '-':
+ negative = 1; /* Fall through to increment position */
+ case '+':
+ p++;
+ }
+
+ number = 0.;
+ exponent = 0;
+ num_digits = 0;
+ num_decimals = 0;
+
+ /* Process string of digits */
+
+ while (isdigit(*p))
+ {
+ number = number * 10. + (*p - '0');
+ p++;
+ num_digits++;
+ }
+
+ /* Process decimal part */
+
+ if (*p == '.')
+ {
+ p++;
+
+ while (isdigit(*p))
+ {
+ number = number * 10. + (*p - '0');
+ p++;
+ num_digits++;
+ num_decimals++;
+ }
+
+ exponent -= num_decimals;
+ }
+
+ if (num_digits == 0)
+ {
+ errno = ERANGE;
+ return 0.0;
+ }
+
+ /* Correct for sign */
+
+ if (negative)
+ {
+ number = -number;
+ }
+
+ /* Process an exponent string */
+
+ if (*p == 'e' || *p == 'E')
+ {
+ /* Handle optional sign */
+
+ negative = 0;
+ switch(*++p)
+ {
+ case '-':
+ negative = 1; /* Fall through to increment pos */
+ case '+':
+ p++;
+ }
+
+ /* Process string of digits */
+
+ n = 0;
+ while (isdigit(*p))
+ {
+ n = n * 10 + (*p - '0');
+ p++;
+ }
+
+ if (negative)
+ {
+ exponent -= n;
+ }
+ else
+ {
+ exponent += n;
+ }
+ }
+
+ if (exponent < __DBL_MIN_EXP__ ||
+ exponent > __DBL_MAX_EXP__)
+ {
+ errno = ERANGE;
+ return infinite;
+ }
+
+ /* Scale the result */
+
+ p10 = 10.;
+ n = exponent;
+ if (n < 0) n = -n;
+ while (n)
+ {
+ if (n & 1)
+ {
+ if (exponent < 0)
+ {
+ number /= p10;
+ }
+ else
+ {
+ number *= p10;
+ }
+ }
+ n >>= 1;
+ p10 *= p10;
+ }
+
+ if (!is_real(number))
+ {
+ errno = ERANGE;
+ }
+
+ if (endptr)
+ {
+ *endptr = p;
+ }
+
+ return number;
+}
+
projects / litex.git / commitdiff