The truncf() function can be implemented just like trunc().
2007-10-04 Bruno Haible <[EMAIL PROTECTED]>
* modules/truncf: New file.
* lib/trunc.c: Make paramerizable through USE_* macros.
* lib/truncf.c: New file.
* m4/truncf.m4: New file.
* lib/math.in.h (truncf): New declaration.
* m4/math_h.m4 (gl_MATH_H_DEFAULTS): Initialize GNULIB_TRUNCF and
HAVE_DECL_TRUNCF.
* modules/math (Makefile.am): Substitute also GNULIB_TRUNCF and
HAVE_DECL_TRUNCF.
* doc/functions/truncf.texi: Mention the 'truncf' module.
*** doc/functions/truncf.texi.orig 2007-10-05 01:05:03.000000000 +0200
--- doc/functions/truncf.texi 2007-10-04 12:38:09.000000000 +0200
***************
*** 4,18 ****
POSIX specification: @url{http://www.opengroup.org/susv3xsh/truncf.html}
! Gnulib module: ---
Portability problems fixed by Gnulib:
@itemize
@end itemize
Portability problems not fixed by Gnulib:
@itemize
- @item
- This function is missing on some platforms:
- FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, AIX 5.1, HP-UX 11, Solaris 9, Interix
3.5.
@end itemize
--- 4,18 ----
POSIX specification: @url{http://www.opengroup.org/susv3xsh/truncf.html}
! Gnulib module: truncf
Portability problems fixed by Gnulib:
@itemize
+ @item
+ This function is missing on some platforms:
+ FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, AIX 5.1, HP-UX 11, Solaris 9, Interix
3.5.
@end itemize
Portability problems not fixed by Gnulib:
@itemize
@end itemize
*** lib/math.in.h.orig 2007-10-05 01:05:03.000000000 +0200
--- lib/math.in.h 2007-10-05 00:22:13.000000000 +0200
***************
*** 65,70 ****
--- 65,71 ----
acosl (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double asinl (long double x);
#endif
***************
*** 76,81 ****
--- 77,83 ----
asinl (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double atanl (long double x);
#endif
***************
*** 87,92 ****
--- 89,95 ----
atanl (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double ceill (long double x);
#endif
***************
*** 98,103 ****
--- 101,107 ----
ceill (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double cosl (long double x);
#endif
***************
*** 109,114 ****
--- 113,119 ----
cosl (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double expl (long double x);
#endif
***************
*** 120,125 ****
--- 125,131 ----
expl (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double floorl (long double x);
#endif
***************
*** 131,136 ****
--- 137,143 ----
floorl (x))
#endif
+
/* Write x as
x = mantissa * 2^exp
where
***************
*** 152,157 ****
--- 159,165 ----
frexpl (x, e))
#endif
+
/* Return x * 2^exp. */
#if @GNULIB_LDEXPL@ && @REPLACE_LDEXPL@
# define ldexpl rpl_ldexpl
***************
*** 167,172 ****
--- 175,181 ----
ldexpl (x, e))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double logl (long double x);
#endif
***************
*** 178,183 ****
--- 187,193 ----
logl (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double sinl (long double x);
#endif
***************
*** 189,194 ****
--- 199,205 ----
sinl (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double sqrtl (long double x);
#endif
***************
*** 200,205 ****
--- 211,217 ----
sqrtl (x))
#endif
+
#if @GNULIB_MATHL@ || [EMAIL PROTECTED]@
extern long double tanl (long double x);
#endif
***************
*** 211,216 ****
--- 223,242 ----
tanl (x))
#endif
+
+ #if @GNULIB_TRUNCF@
+ # if [EMAIL PROTECTED]@
+ # define truncf rpl_truncf
+ extern float truncf (float x);
+ # endif
+ #elif defined GNULIB_POSIXCHECK
+ # undef truncf
+ # define truncf(x) \
+ (GL_LINK_WARNING ("truncf is unportable - " \
+ "use gnulib module truncf for portability"), \
+ truncf (x))
+ #endif
+
#if @GNULIB_TRUNC@
# if [EMAIL PROTECTED]@
# define trunc rpl_trunc
*** lib/trunc.c.orig 2007-10-05 01:05:03.000000000 +0200
--- lib/trunc.c 2007-10-05 00:57:25.000000000 +0200
***************
*** 24,41 ****
#include <float.h>
! /* 2^(DBL_MANT_DIG-1). */
static const double TWO_MANT_DIG =
! /* Assume DBL_MANT_DIG <= 4 * 31.
Use the identity
! n = floor(n/4) + floor((n+1)/4) + floor((n+2)/4) + floor((n+3)/4). */
! (double) (1U << ((DBL_MANT_DIG - 1) / 4))
! * (double) (1U << ((DBL_MANT_DIG - 1 + 1) / 4))
! * (double) (1U << ((DBL_MANT_DIG - 1 + 2) / 4))
! * (double) (1U << ((DBL_MANT_DIG - 1 + 3) / 4));
! double
! trunc (double x)
{
/* The use of 'volatile' guarantees that excess precision bits are dropped
at each addition step and before the following comparison at the caller's
--- 24,59 ----
#include <float.h>
! #ifdef USE_LONG_DOUBLE
! # define FUNC truncl
! # define DOUBLE long double
! # define MANT_DIG LDBL_MANT_DIG
! # define L_(literal) literal##L
! #elif ! defined USE_FLOAT
! # define FUNC trunc
! # define DOUBLE double
! # define MANT_DIG DBL_MANT_DIG
! # define L_(literal) literal
! #else /* defined USE_FLOAT */
! # define FUNC truncf
! # define DOUBLE float
! # define MANT_DIG FLT_MANT_DIG
! # define L_(literal) literal##f
! #endif
!
! /* 2^(MANT_DIG-1). */
static const double TWO_MANT_DIG =
! /* Assume MANT_DIG <= 5 * 31.
Use the identity
! n = floor(n/5) + floor((n+1)/5) + ... + floor((n+4)/5). */
! (DOUBLE) (1U << ((MANT_DIG - 1) / 5))
! * (DOUBLE) (1U << ((MANT_DIG - 1 + 1) / 5))
! * (DOUBLE) (1U << ((MANT_DIG - 1 + 2) / 5))
! * (DOUBLE) (1U << ((MANT_DIG - 1 + 3) / 5))
! * (DOUBLE) (1U << ((MANT_DIG - 1 + 4) / 5));
! DOUBLE
! FUNC (DOUBLE x)
{
/* The use of 'volatile' guarantees that excess precision bits are dropped
at each addition step and before the following comparison at the caller's
***************
*** 43,68 ****
compliant by default, to avoid that the results become platform and
compiler
option dependent. 'volatile' is a portable alternative to gcc's
-ffloat-store option. */
! volatile double y = x;
! volatile double z = y;
! if (z > 0)
{
/* Round to the next integer (nearest or up or down, doesn't matter).
*/
z += TWO_MANT_DIG;
z -= TWO_MANT_DIG;
/* Enforce rounding down. */
if (z > y)
! z -= 1.0;
}
! else if (z < 0)
{
/* Round to the next integer (nearest or up or down, doesn't matter).
*/
z -= TWO_MANT_DIG;
z += TWO_MANT_DIG;
/* Enforce rounding up. */
if (z < y)
! z += 1.0;
}
return z;
}
--- 61,86 ----
compliant by default, to avoid that the results become platform and
compiler
option dependent. 'volatile' is a portable alternative to gcc's
-ffloat-store option. */
! volatile DOUBLE y = x;
! volatile DOUBLE z = y;
! if (z > L_(0.0))
{
/* Round to the next integer (nearest or up or down, doesn't matter).
*/
z += TWO_MANT_DIG;
z -= TWO_MANT_DIG;
/* Enforce rounding down. */
if (z > y)
! z -= L_(1.0);
}
! else if (z < L_(0.0))
{
/* Round to the next integer (nearest or up or down, doesn't matter).
*/
z -= TWO_MANT_DIG;
z += TWO_MANT_DIG;
/* Enforce rounding up. */
if (z < y)
! z += L_(1.0);
}
return z;
}
Changing permissions from . to 100644
*** lib/truncf.c.orig 2003-09-23 19:59:22.000000000 +0200
--- lib/truncf.c 2007-10-04 12:27:09.000000000 +0200
***************
*** 0 ****
--- 1,21 ----
+ /* Round towards zero.
+ Copyright (C) 2007 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 2, 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, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+ /* Written by Bruno Haible <[EMAIL PROTECTED]>, 2007. */
+
+ #define USE_FLOAT
+ #include "trunc.c"
*** m4/math_h.m4.orig 2007-10-05 01:05:03.000000000 +0200
--- m4/math_h.m4 2007-10-04 12:46:10.000000000 +0200
***************
*** 25,30 ****
--- 25,31 ----
GNULIB_MATHL=0; AC_SUBST([GNULIB_MATHL])
GNULIB_SIGNBIT=0; AC_SUBST([GNULIB_SIGNBIT])
GNULIB_TRUNC=0; AC_SUBST([GNULIB_TRUNC])
+ GNULIB_TRUNCF=0; AC_SUBST([GNULIB_TRUNCF])
dnl Assume proper GNU behavior unless another module says otherwise.
HAVE_DECL_ACOSL=1; AC_SUBST([HAVE_DECL_ACOSL])
HAVE_DECL_ASINL=1; AC_SUBST([HAVE_DECL_ASINL])
***************
*** 40,45 ****
--- 41,47 ----
HAVE_DECL_SQRTL=1; AC_SUBST([HAVE_DECL_SQRTL])
HAVE_DECL_TANL=1; AC_SUBST([HAVE_DECL_TANL])
HAVE_DECL_TRUNC=1; AC_SUBST([HAVE_DECL_TRUNC])
+ HAVE_DECL_TRUNCF=1; AC_SUBST([HAVE_DECL_TRUNCF])
REPLACE_FREXP=0; AC_SUBST([REPLACE_FREXP])
REPLACE_FREXPL=0; AC_SUBST([REPLACE_FREXPL])
REPLACE_LDEXPL=0; AC_SUBST([REPLACE_LDEXPL])
Changing permissions from . to 100644
*** m4/truncf.m4.orig 2003-09-23 19:59:22.000000000 +0200
--- m4/truncf.m4 2007-10-05 01:01:19.000000000 +0200
***************
*** 0 ****
--- 1,48 ----
+ # truncf.m4 serial 1
+ dnl Copyright (C) 2007 Free Software Foundation, Inc.
+ dnl This file is free software; the Free Software Foundation
+ dnl gives unlimited permission to copy and/or distribute it,
+ dnl with or without modifications, as long as this notice is preserved.
+
+ AC_DEFUN([gl_FUNC_TRUNCF],
+ [
+ AC_REQUIRE([gl_MATH_H_DEFAULTS])
+ dnl Persuade glibc <math.h> to declare truncf().
+ AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+ dnl Test whether truncf() is declared.
+ AC_CHECK_DECLS([truncf], , , [#include <math.h>])
+ if test "$ac_cv_have_decl_truncf" = yes; then
+ dnl Test whether truncf() can be used without libm.
+ TRUNCF_LIBM=?
+ AC_TRY_LINK([
+ #ifndef __NO_MATH_INLINES
+ # define __NO_MATH_INLINES 1 /* for glibc */
+ #endif
+ #include <math.h>
+ float x;],
+ [x = truncf(x);],
+ [TRUNCF_LIBM=])
+ if test "$TRUNCF_LIBM" = "?"; then
+ save_LIBS="$LIBS"
+ LIBS="$LIBS -lm"
+ AC_TRY_LINK([
+ #ifndef __NO_MATH_INLINES
+ # define __NO_MATH_INLINES 1 /* for glibc */
+ #endif
+ #include <math.h>
+ float x;],
+ [x = truncf(x);],
+ [TRUNCF_LIBM="-lm"])
+ LIBS="$save_LIBS"
+ fi
+ if test "$TRUNCF_LIBM" = "?"; then
+ TRUNCF_LIBM=
+ fi
+ else
+ HAVE_DECL_TRUNCF=0
+ AC_LIBOBJ([truncf])
+ TRUNCF_LIBM=
+ fi
+ AC_SUBST([HAVE_DECL_TRUNCF])
+ AC_SUBST([TRUNCF_LIBM])
+ ])
*** modules/math.orig 2007-10-05 01:05:03.000000000 +0200
--- modules/math 2007-10-04 12:45:48.000000000 +0200
***************
*** 28,33 ****
--- 28,34 ----
-e 's|@''GNULIB_MATHL''@|$(GNULIB_MATHL)|g' \
-e 's|@''GNULIB_SIGNBIT''@|$(GNULIB_SIGNBIT)|g' \
-e 's|@''GNULIB_TRUNC''@|$(GNULIB_TRUNC)|g' \
+ -e 's|@''GNULIB_TRUNCF''@|$(GNULIB_TRUNCF)|g' \
-e 's|@''HAVE_DECL_ACOSL''@|$(HAVE_DECL_ACOSL)|g' \
-e 's|@''HAVE_DECL_ASINL''@|$(HAVE_DECL_ASINL)|g' \
-e 's|@''HAVE_DECL_ATANL''@|$(HAVE_DECL_ATANL)|g' \
***************
*** 42,47 ****
--- 43,49 ----
-e 's|@''HAVE_DECL_SQRTL''@|$(HAVE_DECL_SQRTL)|g' \
-e 's|@''HAVE_DECL_TANL''@|$(HAVE_DECL_TANL)|g' \
-e 's|@''HAVE_DECL_TRUNC''@|$(HAVE_DECL_TRUNC)|g' \
+ -e 's|@''HAVE_DECL_TRUNCF''@|$(HAVE_DECL_TRUNCF)|g' \
-e 's|@''REPLACE_FREXP''@|$(REPLACE_FREXP)|g' \
-e 's|@''REPLACE_FREXPL''@|$(REPLACE_FREXPL)|g' \
-e 's|@''REPLACE_LDEXPL''@|$(REPLACE_LDEXPL)|g' \
Changing permissions from . to 100644
*** modules/truncf.orig 2003-09-23 19:59:22.000000000 +0200
--- modules/truncf 2007-10-05 00:54:39.000000000 +0200
***************
*** 0 ****
--- 1,31 ----
+ Description:
+ truncf() function: round towards zero.
+
+ Files:
+ lib/truncf.c
+ lib/trunc.c
+ m4/truncf.m4
+
+ Depends-on:
+ math
+ extensions
+ float
+
+ configure.ac:
+ gl_FUNC_TRUNCF
+ gl_MATH_MODULE_INDICATOR([truncf])
+
+ Makefile.am:
+
+ Include:
+ <math.h>
+
+ Link:
+ $(TRUNCF_LIBM)
+
+ License:
+ LGPL
+
+ Maintainer:
+ Bruno Haible
+
