Pre-C99 versions of snprintf often had an interface different from the C99 interface: they would return -1 when the buffer was too small, and the "size" argument was not necessarily interpreted the same way. However, the current Gnulib snprintf module doesn't check whether snprintf is C99-compliant, it just checks for its presence. This is a problem with, e.g. Windows, which has such a noncompliant snprintf.
The following patch attempts to remedy the situation. It works fine for me with mingw32/Wine. I suspect that the patch to vasnprintf.c is not the right way to go about things, but I don't know what the preferred method is. vsnprintf probably wants something similar. Comments? Index: lib/vasnprintf.c =================================================================== RCS file: /sources/gnulib/gnulib/lib/vasnprintf.c,v retrieving revision 1.22 diff -u -p -r1.22 vasnprintf.c --- lib/vasnprintf.c 30 Jan 2007 01:07:22 -0000 1.22 +++ lib/vasnprintf.c 16 Feb 2007 05:01:05 -0000 @@ -27,6 +27,9 @@ # include <alloca.h> #endif +/* If we're replacing snprintf with rpl_snprintf, avoid a loop. */ +#undef snprintf + /* Specification. */ #if WIDE_CHAR_VERSION # include "vasnwprintf.h" Index: m4/snprintf.m4 =================================================================== RCS file: /sources/gnulib/gnulib/m4/snprintf.m4,v retrieving revision 1.3 diff -u -p -r1.3 snprintf.m4 --- m4/snprintf.m4 23 Jan 2005 08:06:57 -0000 1.3 +++ m4/snprintf.m4 16 Feb 2007 05:01:06 -0000 @@ -1,12 +1,27 @@ -# snprintf.m4 serial 2 -dnl Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc. +# snprintf.m4 serial 3 +dnl Copyright (C) 2002, 2003, 2004, 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_SNPRINTF], [ - AC_REPLACE_FUNCS(snprintf) + AC_CACHE_CHECK([for C99-compliant snprintf], + [gl_cv_func_snprintf], + [AC_RUN_IFELSE( + [AC_LANG_PROGRAM( + [[#include <stdio.h>]], + [[char s[2]; +return !(snprintf (s, 2, "foo") == 3 && s[0] == 'f' && s[1] == '\0');]])], + [gl_cv_func_snprintf=yes], + [gl_cv_func_snprintf=no], + [gl_cv_func_snprintf=no])]) + + if test $gl_cv_func_snprintf = no; then + AC_LIBOBJ(snprintf) + AC_DEFINE(snprintf, rpl_snprintf, + [Define to rpl_snprintf if the replacement function should be used.]) + fi AC_CHECK_DECLS_ONCE(snprintf) gl_PREREQ_SNPRINTF ]) -- "In the PARTIES partition there is a small section called the BEER. Prior to turning control over to the PARTIES partition, the BIOS must measure the BEER area into PCR[5]." --TCPA PC Specific Implementation Specification
