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diff --git a/gnulib b/gnulib
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-Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1
diff --git a/gnulib/lib/ftoastr.c b/gnulib/lib/ftoastr.c
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+/* floating point to accurate string
+
+ Copyright (C) 2010-2011 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 <http://www.gnu.org/licenses/>. */
+
+/* Written by Paul Eggert. */
+
+/* This code can misbehave on some buggy or older platforms, when
+ operating on arguments on floating types other than 'double', or
+ when given unusual combinations of options. Gnulib's
+ snprintf-posix module works around many of these problems.
+
+ This code relies on sprintf, strtod, etc. operating accurately;
+ otherwise, the resulting strings could be inaccurate or too long. */
+
+#include <config.h>
+
+#include "ftoastr.h"
+
+#include "intprops.h"
+#include <float.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#if LENGTH == 3
+# define FLOAT long double
+# define FLOAT_DIG LDBL_DIG
+# define FLOAT_MIN LDBL_MIN
+# define FLOAT_PREC_BOUND _GL_LDBL_PREC_BOUND
+# define FTOASTR ldtoastr
+# if HAVE_C99_STRTOLD
+# define STRTOF strtold
+# endif
+#elif LENGTH == 2
+# define FLOAT double
+# define FLOAT_DIG DBL_DIG
+# define FLOAT_MIN DBL_MIN
+# define FLOAT_PREC_BOUND _GL_DBL_PREC_BOUND
+# define FTOASTR dtoastr
+#else
+# define LENGTH 1
+# define FLOAT float
+# define FLOAT_DIG FLT_DIG
+# define FLOAT_MIN FLT_MIN
+# define FLOAT_PREC_BOUND _GL_FLT_PREC_BOUND
+# define FTOASTR ftoastr
+# if HAVE_STRTOF
+# define STRTOF strtof
+# endif
+#endif
+
+/* On pre-C99 hosts, approximate strtof and strtold with strtod. This
+ may generate one or two extra digits, but that's better than not
+ working at all. */
+#ifndef STRTOF
+# define STRTOF strtod
+#endif
+
+/* On hosts where it's not known that snprintf works, use sprintf to
+ implement the subset needed here. Typically BUFSIZE is big enough
+ and there's little or no performance hit. */
+#if ! GNULIB_SNPRINTF
+# undef snprintf
+# define snprintf ftoastr_snprintf
+static int
+ftoastr_snprintf (char *buf, size_t bufsize, char const *format,
+ int width, int prec, FLOAT x)
+{
+ char width_0_buffer[LENGTH == 1 ? FLT_BUFSIZE_BOUND
+ : LENGTH == 2 ? DBL_BUFSIZE_BOUND
+ : LDBL_BUFSIZE_BOUND];
+ int n = width;
+ if (bufsize < sizeof width_0_buffer)
+ {
+ n = sprintf (width_0_buffer, format, 0, prec, x);
+ if (n < 0)
+ return n;
+ if (n < width)
+ n = width;
+ }
+ if (n < bufsize)
+ n = sprintf (buf, format, width, prec, x);
+ return n;
+}
+#endif
+
+int
+FTOASTR (char *buf, size_t bufsize, int flags, int width, FLOAT x)
+{
+ /* The following method is simple but slow.
+ For ideas about speeding things up, please see:
+
+ Florian Loitsch, Printing floating-point numbers quickly and accurately
+ with integers. ACM SIGPLAN notices 46, 6 (June 2010), 233-243
+ <http://dx.doi.org/10.1145/1809028.1806623>; also see the
+ 2010-03-21 draft <http://florian.loitsch.com/tmp/article.pdf>. */
+
+ char format[sizeof "%-+ 0*.*Lg"];
+ FLOAT abs_x = x < 0 ? -x : x;
+ int prec;
+
+ char *p = format;
+ *p++ = '%';
+
+ /* Support flags that generate output parsable by strtof. */
+ *p = '-'; p += (flags & FTOASTR_LEFT_JUSTIFY ) != 0;
+ *p = '+'; p += (flags & FTOASTR_ALWAYS_SIGNED ) != 0;
+ *p = ' '; p += (flags & FTOASTR_SPACE_POSITIVE) != 0;
+ *p = '0'; p += (flags & FTOASTR_ZERO_PAD ) != 0;
+
+ *p++ = '*';
+ *p++ = '.';
+ *p++ = '*';
+ *p = 'L'; p += 2 < LENGTH;
+ *p++ = flags & FTOASTR_UPPER_E ? 'G' : 'g';
+ *p = '\0';
+
+ for (prec = abs_x < FLOAT_MIN ? 1 : FLOAT_DIG; ; prec++)
+ {
+ int n = snprintf (buf, bufsize, format, width, prec, x);
+ if (n < 0
+ || FLOAT_PREC_BOUND <= prec
+ || (n < bufsize && STRTOF (buf, NULL) == x))
+ return n;
+ }
+}