1 files changed, 135 insertions, 0 deletions
diff --git a/lib/c-strtod.c b/lib/c-strtod.c
new file mode 100644
index 0000000..80739ee
--- /dev/null
+++ b/lib/c-strtod.c
@@ -0,0 +1,135 @@
+/* Convert string to double, using the C locale.
+
+   Copyright (C) 2003-2004, 2006, 2009-2022 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
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert.  */
+
+#include <config.h>
+
+#include "c-strtod.h"
+
+#include <errno.h>
+#include <locale.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if LONG
+# define C_STRTOD c_strtold
+# define DOUBLE long double
+# define STRTOD_L strtold_l
+# define HAVE_GOOD_STRTOD_L (HAVE_STRTOLD_L && !GNULIB_defined_strtold_function)
+# define STRTOD strtold
+#else
+# define C_STRTOD c_strtod
+# define DOUBLE double
+# define STRTOD_L strtod_l
+# define HAVE_GOOD_STRTOD_L (HAVE_STRTOD_L && !GNULIB_defined_strtod_function)
+# define STRTOD strtod
+#endif
+
+#if defined LC_ALL_MASK \
+    && ((LONG ? HAVE_GOOD_STRTOLD_L : HAVE_GOOD_STRTOD_L) \
+        || HAVE_WORKING_USELOCALE)
+
+/* Cache for the C locale object.
+   Marked volatile so that different threads see the same value
+   (avoids locking).  */
+static volatile locale_t c_locale_cache;
+
+/* Return the C locale object, or (locale_t) 0 with errno set
+   if it cannot be created.  */
+static locale_t
+c_locale (void)
+{
+  if (!c_locale_cache)
+    c_locale_cache = newlocale (LC_ALL_MASK, "C", (locale_t) 0);
+  return c_locale_cache;
+}
+
+#endif
+
+DOUBLE
+C_STRTOD (char const *nptr, char **endptr)
+{
+  DOUBLE r;
+
+#if defined LC_ALL_MASK \
+    && ((LONG ? HAVE_GOOD_STRTOLD_L : HAVE_GOOD_STRTOD_L) \
+        || HAVE_WORKING_USELOCALE)
+
+  locale_t locale = c_locale ();
+  if (!locale)
+    {
+      if (endptr)
+        *endptr = (char *) nptr;
+      return 0; /* errno is set here */
+    }
+
+# if (LONG ? HAVE_GOOD_STRTOLD_L : HAVE_GOOD_STRTOD_L)
+
+  r = STRTOD_L (nptr, endptr, locale);
+
+# else /* HAVE_WORKING_USELOCALE */
+
+  locale_t old_locale = uselocale (locale);
+  if (old_locale == (locale_t)0)
+    {
+      if (endptr)
+        *endptr = (char *) nptr;
+      return 0; /* errno is set here */
+    }
+
+  r = STRTOD (nptr, endptr);
+
+  int saved_errno = errno;
+  if (uselocale (old_locale) == (locale_t)0)
+    /* We can't switch back to the old locale.  The thread is hosed.  */
+    abort ();
+  errno = saved_errno;
+
+# endif
+
+#else
+
+  char *saved_locale = setlocale (LC_NUMERIC, NULL);
+
+  if (saved_locale)
+    {
+      saved_locale = strdup (saved_locale);
+      if (saved_locale == NULL)
+        {
+          if (endptr)
+            *endptr = (char *) nptr;
+          return 0; /* errno is set here */
+        }
+      setlocale (LC_NUMERIC, "C");
+    }
+
+  r = STRTOD (nptr, endptr);
+
+  if (saved_locale)
+    {
+      int saved_errno = errno;
+
+      setlocale (LC_NUMERIC, saved_locale);
+      free (saved_locale);
+      errno = saved_errno;
+    }
+
+#endif
+
+  return r;
+}