Re: [PATCH] ftoastr: new module, for lossless conversion of floats to short strings

[Paul Eggert]

On 11/18/10 13:59, Paul Eggert wrote:

> Something
> like the following patch should address that issue, I expect.

I installed this slightly-different patch:

>From a632f45b2e5ce87e0aad94a39c658dac1a29fcd2 Mon Sep 17 00:00:00 2001
From: Paul Eggert <address@hidden>
Date: Thu, 18 Nov 2010 16:49:05 -0800
Subject: [PATCH] ftoastr: port to hosts lacking strtof and strtold

Problem reported by Bruno Haible in
<http://lists.gnu.org/archive/html/bug-gnulib/2010-11/msg00242.html>.
* lib/ftoastr.c (STRTOF): Define to strtod if in a pre-C99
environment and strtold (and presumably strtof) are not available.
* modules/ftoastr (Files): Add m4/c-strtod.m4.
(configure.ac): Require gl_C99_STRTOLD.
---
 ChangeLog       |   10 ++++++++++
 lib/ftoastr.c   |    8 ++++++++
 modules/ftoastr |    2 ++
 3 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 0ab0af3..c923b68 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2010-11-18  Paul Eggert  <address@hidden>
+
+       ftoastr: port to hosts lacking strtof and strtold
+       Problem reported by Bruno Haible in
+       <http://lists.gnu.org/archive/html/bug-gnulib/2010-11/msg00242.html>.
+       * lib/ftoastr.c (STRTOF): Define to strtod if in a pre-C99
+       environment and strtold (and presumably strtof) are not available.
+       * modules/ftoastr (Files): Add m4/c-strtod.m4.
+       (configure.ac): Require gl_C99_STRTOLD.
+
 2010-11-17  Paul Eggert  <address@hidden>
 
        intprops: new macro INT_BITS_STRLEN_BOUND
diff --git a/lib/ftoastr.c b/lib/ftoastr.c
index 25e0705..ddc5251 100644
--- a/lib/ftoastr.c
+++ b/lib/ftoastr.c
@@ -48,6 +48,14 @@
 # define STRTOF strtof
 #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.  Assume that strtof works if strtold does.  */
+#if LENGTH != 2 && ! HAVE_C99_STRTOLD
+# undef STRTOF
+# define STRTOF strtod
+#endif
+
 int
 FTOASTR (char *buf, size_t bufsize, int flags, int width, FLOAT x)
 {
diff --git a/modules/ftoastr b/modules/ftoastr
index fbc0cba..64d0a77 100644
--- a/modules/ftoastr
+++ b/modules/ftoastr
@@ -6,11 +6,13 @@ lib/ftoastr.h
 lib/ftoastr.c
 lib/dtoastr.c
 lib/ldtoastr.c
+m4/c-strtod.m4
 
 Depends-on:
 intprops
 
 configure.ac:
+AC_REQUIRE([gl_C99_STRTOLD])
 
 Makefile.am:
 lib_SOURCES += ftoastr.h ftoastr.c dtoastr.c ldtoastr.c
-- 
1.7.2