1 files changed, 63 insertions, 0 deletions
diff --git a/stdlib/strtod_nan_main.c b/stdlib/strtod_nan_main.c
new file mode 100644
index 0000000000..10b1be090e
--- /dev/null
+++ b/stdlib/strtod_nan_main.c
@@ -0,0 +1,63 @@
+/* Convert string for NaN payload to corresponding NaN.
+   Copyright (C) 1997-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C 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.
+
+   The GNU C 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 the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <ieee754.h>
+#include <locale.h>
+#include <math.h>
+#include <stdlib.h>
+#include <wchar.h>
+
+
+/* If STR starts with an optional n-char-sequence as defined by ISO C
+   (a sequence of ASCII letters, digits and underscores), followed by
+   ENDC, return a NaN whose payload is set based on STR.  Otherwise,
+   return a default NAN.  If ENDPTR is not NULL, set *ENDPTR to point
+   to the character after the initial n-char-sequence.  */
+
+internal_function
+FLOAT
+STRTOD_NAN (const STRING_TYPE *str, STRING_TYPE **endptr, STRING_TYPE endc)
+{
+  const STRING_TYPE *cp = str;
+
+  while ((*cp >= L_('0') && *cp <= L_('9'))
+	 || (*cp >= L_('A') && *cp <= L_('Z'))
+	 || (*cp >= L_('a') && *cp <= L_('z'))
+	 || *cp == L_('_'))
+    ++cp;
+
+  FLOAT retval = NAN;
+  if (*cp != endc)
+    goto out;
+
+  /* This is a system-dependent way to specify the bitmask used for
+     the NaN.  We expect it to be a number which is put in the
+     mantissa of the number.  */
+  STRING_TYPE *endp;
+  unsigned long long int mant;
+
+  mant = STRTOULL (str, &endp, 0);
+  if (endp == cp)
+    SET_MANTISSA (retval, mant);
+
+ out:
+  if (endptr != NULL)
+    *endptr = (STRING_TYPE *) cp;
+  return retval;
+}
+libc_hidden_def (STRTOD_NAN)