new module 'printf-posix'

[Bruno Haible]

This module adds a POSIX compliant printf() function. This is the last module
in this series.

Redefining 'printf' is less easy than redefining 'vprintf' etc., because
gcc allows to use the symbol 'printf' in __attribute__s of function
declarations. Working around this requires some tricks. You can also call
it monstrous hacks. Have fun :-)

2007-03-09  Bruno Haible  <address@hidden>

        * modules/printf-posix: New file.
        * lib/printf.c: New file.
        * m4/printf-posix-rpl.m4: New file.
        * m4/stdio_h.m4 (gl_STDIO_H_DEFAULTS): Set also GNULIB_PRINTF_POSIX,
        REPLACE_PRINTF.
        * lib/stdio_.h (printf): New declaration.
        (format, __format__, ____printf____, ____scanf____): New macros.
        * modules/stdio (Makefile.am): Substitute also GNULIB_PRINTF_POSIX,
        REPLACE_PRINTF.

========================= modules/printf-posix ================================
Description:
POSIX compatible printf() function: print formatted output to standard output

Files:
lib/printf.c
m4/printf-posix-rpl.m4
m4/printf.m4

Depends-on:
stdio
vfprintf-posix

configure.ac:
gl_FUNC_PRINTF_POSIX
gl_STDIO_MODULE_INDICATOR([printf-posix])

Makefile.am:

Include:
<stdio.h>

License:
LGPL

Maintainer:
Bruno Haible

========================== lib/printf.c =======================================
/* Formatted output to a stream.
   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.  */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

/* Specification.  */
#include <stdio.h>

#include <stdarg.h>

/* Print formatted output to standard output.
   Return string length of formatted string.  On error, return a negative
   value.  */
int
printf (const char *format, ...)
{
  int retval;
  va_list args;

  va_start (args, format);
  retval = vfprintf (stdout, format, args);
  va_end (args);

  return retval;
}
======================= m4/printf-posix-rpl.m4 ================================
# printf-posix-rpl.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_PRINTF_POSIX],
[
  AC_REQUIRE([gl_FUNC_VFPRINTF_POSIX])
  if test $gl_cv_func_vfprintf_posix = no; then
    gl_REPLACE_PRINTF
  fi
])

AC_DEFUN([gl_REPLACE_PRINTF],
[
  AC_REQUIRE([gl_STDIO_H_DEFAULTS])
  AC_LIBOBJ([printf])
  REPLACE_PRINTF=1
  gl_PREREQ_PRINTF
])

AC_DEFUN([gl_PREREQ_PRINTF], [:])
===============================================================================
*** m4/stdio_h.m4       9 Mar 2007 03:42:25 -0000       1.8
--- m4/stdio_h.m4       10 Mar 2007 01:09:47 -0000
***************
*** 22,27 ****
--- 22,28 ----
  AC_DEFUN([gl_STDIO_H_DEFAULTS],
  [
    GNULIB_FPRINTF_POSIX=0;  AC_SUBST([GNULIB_FPRINTF_POSIX])
+   GNULIB_PRINTF_POSIX=0;   AC_SUBST([GNULIB_PRINTF_POSIX])
    GNULIB_SNPRINTF=0;       AC_SUBST([GNULIB_SNPRINTF])
    GNULIB_SPRINTF_POSIX=0;  AC_SUBST([GNULIB_SPRINTF_POSIX])
    GNULIB_VFPRINTF_POSIX=0; AC_SUBST([GNULIB_VFPRINTF_POSIX])
***************
*** 31,36 ****
--- 32,38 ----
    dnl Assume proper GNU behavior unless another module says otherwise.
    REPLACE_FPRINTF=0;       AC_SUBST([REPLACE_FPRINTF])
    REPLACE_VFPRINTF=0;      AC_SUBST([REPLACE_VFPRINTF])
+   REPLACE_PRINTF=0;        AC_SUBST([REPLACE_PRINTF])
    REPLACE_VPRINTF=0;       AC_SUBST([REPLACE_VPRINTF])
    REPLACE_SNPRINTF=0;      AC_SUBST([REPLACE_SNPRINTF])
    HAVE_DECL_SNPRINTF=1;    AC_SUBST([HAVE_DECL_SNPRINTF])
*** lib/stdio_.h        9 Mar 2007 03:42:25 -0000       1.10
--- lib/stdio_.h        10 Mar 2007 01:09:47 -0000
***************
*** 68,73 ****
--- 68,93 ----
       vfprintf (s, f, a))
  #endif
  
+ #if @GNULIB_PRINTF_POSIX@
+ # if @REPLACE_PRINTF@
+ /* Don't break __attribute__((format(printf,M,N))).  */
+ #  define printf __printf__
+ extern int printf (const char *format, ...);
+ # endif
+ #elif defined GNULIB_POSIXCHECK
+ # undef printf
+ # define printf \
+     (GL_LINK_WARNING ("printf is not always POSIX compliant - " \
+                       "use gnulib module printf-posix for portable " \
+                       "POSIX compliance"), \
+      printf)
+ /* Don't break __attribute__((format(printf,M,N))).  */
+ # define format(kind,m,n) format (__##kind##__, m, n)
+ # define __format__(kind,m,n) __format__ (__##kind##__, m, n)
+ # define ____printf____ __printf__
+ # define ____scanf____ __scanf__
+ #endif
+ 
  #if @GNULIB_VPRINTF_POSIX@
  # if @REPLACE_VPRINTF@
  #  define vprintf rpl_vprintf
*** modules/stdio       9 Mar 2007 03:42:25 -0000       1.8
--- modules/stdio       10 Mar 2007 01:09:47 -0000
***************
*** 22,27 ****
--- 22,28 ----
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */' && \
          sed -e 's|@''ABSOLUTE_STDIO_H''@|$(ABSOLUTE_STDIO_H)|g' \
              -e 's|@''GNULIB_FPRINTF_POSIX''@|$(GNULIB_FPRINTF_POSIX)|g' \
+             -e 's|@''GNULIB_PRINTF_POSIX''@|$(GNULIB_PRINTF_POSIX)|g' \
              -e 's|@''GNULIB_SNPRINTF''@|$(GNULIB_SNPRINTF)|g' \
              -e 's|@''GNULIB_SPRINTF_POSIX''@|$(GNULIB_SPRINTF_POSIX)|g' \
              -e 's|@''GNULIB_VFPRINTF_POSIX''@|$(GNULIB_VFPRINTF_POSIX)|g' \
***************
*** 30,35 ****
--- 31,37 ----
              -e 's|@''GNULIB_VSPRINTF_POSIX''@|$(GNULIB_VSPRINTF_POSIX)|g' \
              -e 's|@''REPLACE_FPRINTF''@|$(REPLACE_FPRINTF)|g' \
              -e 's|@''REPLACE_VFPRINTF''@|$(REPLACE_VFPRINTF)|g' \
+             -e 's|@''REPLACE_PRINTF''@|$(REPLACE_PRINTF)|g' \
              -e 's|@''REPLACE_VPRINTF''@|$(REPLACE_VPRINTF)|g' \
              -e 's|@''REPLACE_SNPRINTF''@|$(REPLACE_SNPRINTF)|g' \
              -e 's|@''HAVE_DECL_SNPRINTF''@|$(HAVE_DECL_SNPRINTF)|g' \