Replace our ancient dtoa/strtod implementation with the gdtoa

package, a more recent, generalized set of routines.  Among the
changes:
- Declare strtof() and strtold() in stdlib.h.
- Add glue to libc to support these routines for all kinds
  of ``long double''.
- Update printf() to reflect the fact that dtoa works slightly
  differently now.

As soon as I see that nothing has blown up, I will kill
src/lib/libc/stdlib/strtod.c.  Soon printf() will be able
to use the new routines to output long doubles without loss
of precision, but numerous bugs in the existing code must
be addressed first.

Reviewed by:	bde (briefly), mike (mentor), obrien

1 files changed, 45 insertions, 0 deletions

diff --git a/lib/libc/gdtoa/machdep_ldisx.c b/lib/libc/gdtoa/machdep_ldisx.c
new file mode 100644
index 0000000..1920c39
--- /dev/null
+++ b/lib/libc/gdtoa/machdep_ldisx.c
@@ -0,0 +1,45 @@
+/*-
+ * Copyright (c) 2003 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+/*
+ * Machine-dependent glue to integrate David Gay's gdtoa
+ * package into libc for architectures where a long double
+ * is an IEEE extended precision number.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "gdtoaimp.h"
+
+long double
+strtold(const char * __restrict s, char ** __restrict sp)
+{
+	long double result;
+
+	strtopx(s, sp, result);
+	return result;
+}