Add strtold()

include/stdlib.h

@@ -80,13 +80,6 @@
 #  define environ get_environ_ptr()
 #endif
 
-/* The function strtold() is not currently implemented in NuttX.  Ideally, a
- * custom implementation should be provided because, of course, there is a
- * loss of 32-bits of accuracy in this conversion.
- */
-
-#define strtold(a,b) (long double)strtod(a,b)
-
 /****************************************************************************
  * Public Type Definitions
  ****************************************************************************/
@@ -197,8 +190,13 @@ long long strtoll(FAR const char *nptr, FAR char **endptr, int base);
 unsigned long long strtoull(FAR const char *nptr, FAR char **endptr,
                             int base);
 #endif
-double_t  strtod(FAR const char *str, FAR char **endptr);
 float     strtof(FAR const char *str, FAR char **endptr);
+#ifdef CONFIG_HAVE_DOUBLE
+double    strtod(FAR const char *str, FAR char **endptr);
+#endif
+#ifdef CONFIG_HAVE_LONG_DOUBLE
+long double strtold(FAR const char *str, FAR char **endptr);
+#endif
 
 #define atoi(nptr)  ((int)strtol((nptr), NULL, 10))
 #define atol(nptr)  strtol((nptr), NULL, 10)

libc/stdlib/Make.defs

@@ -39,7 +39,7 @@ CSRCS += lib_abs.c lib_abort.c lib_div.c lib_ldiv.c lib_lldiv.c
 CSRCS += lib_imaxabs.c lib_itoa.c lib_labs.c lib_llabs.c
 CSRCS += lib_bsearch.c lib_rand.c lib_qsort.c lib_srand.c
 CSRCS += lib_strtol.c lib_strtoll.c lib_strtoul.c lib_strtoull.c
-CSRCS += lib_strtod.c lib_strtof.c lib_checkbase.c
+CSRCS += lib_strtod.c lib_strtof.c lib_strtold.c lib_checkbase.c
 
 ifeq ($(CONFIG_FS_WRITABLE),y)
 CSRCS += lib_mktemp.c lib_mkstemp.c

libc/stdlib/lib_strtod.c

@@ -71,7 +71,7 @@
 
 static inline int is_real(double x)
 {
-  const double_t infinite = 1.0/0.0;
+  const double infinite = 1.0/0.0;
   return (x < infinite) && (x >= -infinite);
 }
 
@@ -87,9 +87,9 @@ static inline int is_real(double x)
  *
  ****************************************************************************/
 
-double_t strtod(FAR const char *str, FAR char **endptr)
+double strtod(FAR const char *str, FAR char **endptr)
 {
-  double_t number;
+  double number;
   int exponent;
   int negative;
   FAR char *p = (FAR char *) str;
@@ -97,7 +97,7 @@ double_t strtod(FAR const char *str, FAR char **endptr)
   int n;
   int num_digits;
   int num_decimals;
-  const double_t infinite = 1.0/0.0;
+  const double infinite = 1.0/0.0;
 
   /* Skip leading whitespace */
 

libc/stdlib/lib_strtof.c

@@ -48,8 +48,6 @@
 #include <ctype.h>
 #include <errno.h>
 
-#ifdef CONFIG_HAVE_DOUBLE
-
 /****************************************************************************
  * Pre-processor definitions
  ****************************************************************************/
@@ -248,5 +246,3 @@ errout:
 
   return number;
 }
-
-#endif /* CONFIG_HAVE_DOUBLE */

libc/stdlib/lib_strtold.c

@@ -0,0 +1,248 @@
+/****************************************************************************
+ * libc/stdlib/lib_strtod.c
+ * Convert string to long 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 <nuttx/config.h>
+#include <nuttx/compiler.h>
+
+#include <stdlib.h>
+#include <ctype.h>
+#include <errno.h>
+
+#ifdef CONFIG_HAVE_LONG_DOUBLE
+
+/****************************************************************************
+ * 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(__LDBL_MIN_EXP__) || !defined(__LDBL_MAX_EXP__)
+#  ifdef CONFIG_CPP_HAVE_WARNING
+#    warning "Size of exponent is unknown"
+#  endif
+#  undef  __LDBL_MIN_EXP__
+#  define __LDBL_MIN_EXP__ (-1021)
+#  undef  __LDBL_MAX_EXP__
+#  define __LDBL_MAX_EXP__ (1024)
+#endif
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+static inline int is_real(long double x)
+{
+  const long double infinite = 1.0L/0.0L;
+  return (x < infinite) && (x >= -infinite);
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/***************************************************(************************
+ * Name: strtold
+ *
+ * Description:
+ *   Convert a string to a long double value
+ *
+ ****************************************************************************/
+
+long double strtold(FAR const char *str, FAR char **endptr)
+{
+  long double number;
+  int exponent;
+  int negative;
+  FAR char *p = (FAR char *) str;
+  long double p10;
+  int n;
+  int num_digits;
+  int num_decimals;
+  const long double infinite = 1.0L/0.0L;
+
+  /* Skip leading whitespace */
+
+  while (isspace(*p))
+    {
+      p++;
+    }
+
+  /* Handle optional sign */
+
+  negative = 0;
+  switch (*p)
+    {
+    case '-':
+      negative = 1; /* Fall through to increment position */
+    case '+':
+      p++;
+    default:
+      break;
+    }
+
+  number       = 0.0L;
+  exponent     = 0;
+  num_digits   = 0;
+  num_decimals = 0;
+
+  /* Process string of digits */
+
+  while (isdigit(*p))
+    {
+      number = number * 10.0L + (long double)(*p - '0');
+      p++;
+      num_digits++;
+    }
+
+  /* Process decimal part */
+
+  if (*p == '.')
+    {
+      p++;
+
+      while (isdigit(*p))
+      {
+        number = number * 10.0L + (long double)(*p - '0');
+        p++;
+        num_digits++;
+        num_decimals++;
+      }
+
+      exponent -= num_decimals;
+    }
+
+  if (num_digits == 0)
+    {
+      set_errno(ERANGE);
+      number = 0.0L;
+      goto errout;
+    }
+
+  /* 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++;
+        default:
+          break;
+        }
+
+      /* Process string of digits */
+
+      n = 0;
+      while (isdigit(*p))
+        {
+          n = n * 10 + (*p - '0');
+          p++;
+        }
+
+      if (negative)
+        {
+          exponent -= n;
+        }
+      else
+        {
+          exponent += n;
+        }
+    }
+
+  if (exponent < __LDBL_MIN_EXP__ ||
+      exponent > __LDBL_MAX_EXP__)
+    {
+      set_errno(ERANGE);
+      number = infinite;
+      goto errout;
+    }
+
+  /* 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))
+    {
+      set_errno(ERANGE);
+    }
+
+errout:
+  if (endptr)
+    {
+      *endptr = p;
+    }
+
+  return number;
+}
+
+#endif /* CONFIG_HAVE_LONG_DOUBLE */