Fix various problems in 'obstack-printf' module.

ChangeLog

@@ -1,3 +1,16 @@
+2008-06-14  Bruno Haible  <bruno@clisp.org>
+
+	* lib/obstack_printf.c (obstack_vprintf): Define the stack-allocated
+	array size as a constant, not as a const variable.
+	* m4/obstack-printf.m4 (gl_FUNC_OBSTACK_PRINTF): Require
+	AC_USE_SYSTEM_EXTENSIONS.
+	* m4/obstack-printf-posix.m4 (gl_FUNC_OBSTACK_PRINTF_POSIX): Likewise.
+	Test whether the obstack_printf function actually exists.
+	* modules/obstack-printf (Depends-on): Add extensions.
+	(Include): Remove obstack.h.
+	* modules/obstack-printf-posix (Depends-on): Add extensions.
+	(Include): Remove obstack.h.
+
 2008-06-13  Eric Blake  <ebb9@byu.net>
 
 	Add obstack-printf and obstack-printf-posix modules.

lib/obstack_printf.c

@@ -58,16 +58,16 @@ obstack_vprintf (struct obstack *obs, const char *format, va_list args)
      stack-allocated buffer and copy, to reduce the likelihood of a
      small-size malloc.  Otherwise, print directly into the
      obstack.  */
-  const size_t cutoff = 1024;
+  enum { CUTOFF = 1024 };
-  char buf[cutoff];
+  char buf[CUTOFF];
   char *base = obstack_next_free (obs);
   size_t len = obstack_room (obs);
   char *str;
 
-  if (len < cutoff)
+  if (len < CUTOFF)
     {
       base = buf;
-      len = cutoff;
+      len = CUTOFF;
     }
   str = vasnprintf (base, &len, format, args);
   if (!str)

m4/obstack-printf-posix.m4

@@ -1,4 +1,4 @@
-# obstack-printf-posix.m4 serial 1
+# obstack-printf-posix.m4 serial 2
 dnl Copyright (C) 2008 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -6,6 +6,9 @@ dnl with or without modifications, as long as this notice is preserved.
 
 AC_DEFUN([gl_FUNC_OBSTACK_PRINTF_POSIX],
 [
+  dnl Persuade glibc <stdio.h> to declare obstack_printf(), obstack_vprintf().
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
   AC_REQUIRE([gl_PRINTF_SIZES_C99])
   AC_REQUIRE([gl_PRINTF_LONG_DOUBLE])
   AC_REQUIRE([gl_PRINTF_INFINITE])
@@ -20,6 +23,8 @@ AC_DEFUN([gl_FUNC_OBSTACK_PRINTF_POSIX],
   AC_REQUIRE([gl_PRINTF_PRECISION])
   AC_REQUIRE([gl_PRINTF_ENOMEM])
   gl_cv_func_obstack_printf_posix=no
+  AC_CHECK_FUNCS_ONCE([obstack_printf])
+  if test $ac_cv_func_obstack_printf = yes ; then
     case "$gl_cv_func_printf_sizes_c99" in
       *yes)
         case "$gl_cv_func_printf_long_double" in
@@ -75,6 +80,7 @@ AC_DEFUN([gl_FUNC_OBSTACK_PRINTF_POSIX],
         esac
         ;;
     esac
+  fi
   if test $gl_cv_func_obstack_printf_posix = no; then
     gl_PREREQ_VASNPRINTF_LONG_DOUBLE
     gl_PREREQ_VASNPRINTF_INFINITE_DOUBLE

m4/obstack-printf.m4

@@ -1,4 +1,4 @@
-# obstack-printf.m4 serial 1
+# obstack-printf.m4 serial 2
 dnl Copyright (C) 2008 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -10,6 +10,9 @@ dnl obstack_vprintf behaves identically, so we only test for one.
 
 AC_DEFUN([gl_FUNC_OBSTACK_PRINTF],
 [
+  dnl Persuade glibc <stdio.h> to declare obstack_printf(), obstack_vprintf().
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
   AC_REQUIRE([gl_STDIO_H_DEFAULTS])
   AC_CHECK_FUNCS_ONCE([obstack_printf])
   if test $ac_cv_func_obstack_printf = no ; then

modules/obstack-printf

@@ -9,6 +9,7 @@ Depends-on:
 obstack
 stdio
 vasnprintf
+extensions
 
 configure.ac:
 gl_FUNC_OBSTACK_PRINTF
@@ -17,7 +18,6 @@ gl_STDIO_MODULE_INDICATOR([obstack-printf])
 Makefile.am:
 
 Include:
-"obstack.h"
 <stdio.h>
 
 License:

modules/obstack-printf-posix

@@ -10,6 +10,7 @@ Depends-on:
 obstack
 stdio
 vasnprintf-posix
+extensions
 
 configure.ac:
 gl_FUNC_OBSTACK_PRINTF_POSIX
@@ -18,7 +19,6 @@ gl_STDIO_MODULE_INDICATOR([obstack-printf-posix])
 Makefile.am:
 
 Include:
-"obstack.h"
 <stdio.h>
 
 License: