fseek: avoid compilation failure when fflush is replaced

./gnulib-tool --import fseek fwritable failed on Debian, due
to broken fflush() pulling in rpl_fseeko that mistakenly
overwrote fseek() as function-like macro.

* m4/fseek.m4 (gl_REPLACE_FSEEK): New macro.
* m4/fseeko.m4 (gl_REPLACE_FSEEKO): Also replace fseek, if fseek
module is in use.
* lib/stdio.in.h (GNULIB_FSEEKO): Only poison fseek if fseek
module is not in use; since REPLACE_FSEEK worked otherwise.
(GNULIB_FTELLO): Likewise for ftell.
Reported by Ian Beckwith and others.

Signed-off-by: Eric Blake <ebb9@byu.net>

diff --git a/ChangeLog b/ChangeLog
index e1143f61a74b908afe6713ebc161b443f9c615d6..793ae5062efea68547ad70b435c799aea7805259 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,10 +1,21 @@
+2009-10-27  Eric Blake  <ebb9@byu.net>
+
+       fseek: avoid compilation failure when fflush is replaced
+       * m4/fseek.m4 (gl_REPLACE_FSEEK): New macro.
+       * m4/fseeko.m4 (gl_REPLACE_FSEEKO): Also replace fseek, if fseek
+       module is in use.
+       * lib/stdio.in.h (GNULIB_FSEEKO): Only poison fseek if fseek
+       module is not in use; since REPLACE_FSEEK worked otherwise.
+       (GNULIB_FTELLO): Likewise for ftell.
+       Reported by Ian Beckwith and others.
+
 2009-10-27  Bruno Haible  <bruno@clisp.org>
 
        * lib/isnan.c (rpl_isnan[fdl]): Repeat the specification declaration.
        Reported by Jim Meyering.
 
 2009-10-27  Jim Meyering  <jim@meyering.net>
-            Bruno Haible  <bruno@clisp.org>
+           Bruno Haible  <bruno@clisp.org>
 
        Avoid warning despite dropping the return value of fwrite.
        * lib/unicodeio.c: Include ignore-value.h.

diff --git a/lib/stdio.in.h b/lib/stdio.in.h
index 7a0bc12d39321780d4223093678d9207400b12b8..d0ffa59863492649cb12d6000845a4d3cfcb411f 100644 (file)
--- a/lib/stdio.in.h
+++ b/lib/stdio.in.h
@@ -227,7 +227,14 @@ extern int rpl_fseek (FILE *fp, long offset, int whence);
    fflush(), and which detect pipes.  */
 #  define fseeko rpl_fseeko
 extern int fseeko (FILE *fp, off_t offset, int whence);
-#  define fseek(fp, offset, whence) fseeko (fp, (off_t)(offset), whence)
+#  if !@GNULIB_FSEEK@
+#   undef fseek
+#   define fseek(f,o,w) \
+     (GL_LINK_WARNING ("fseek cannot handle files larger than 4 GB " \
+                       "on 32-bit platforms - " \
+                       "use fseeko function for handling of large files"), \
+      fseeko (f, o, w))
+#  endif
 # endif
 #elif defined GNULIB_POSIXCHECK
 # undef fseeko
@@ -263,7 +270,14 @@ extern long rpl_ftell (FILE *fp);
 # if @REPLACE_FTELLO@
 #  define ftello rpl_ftello
 extern off_t ftello (FILE *fp);
-#  define ftell(fp) ftello (fp)
+#  if !@GNULIB_FTELL@
+#   undef ftell
+#   define ftell(f) \
+     (GL_LINK_WARNING ("ftell cannot handle files larger than 4 GB " \
+                       "on 32-bit platforms - " \
+                       "use ftello function for handling of large files"), \
+      ftello (f))
+#  endif
 # endif
 #elif defined GNULIB_POSIXCHECK
 # undef ftello

diff --git a/m4/fseek.m4 b/m4/fseek.m4
index 80e4501083100cb9190718d964539df025c22ea3..c33297dc5b581101505a4eb26221c15ef88f02bd 100644 (file)
--- a/m4/fseek.m4
+++ b/m4/fseek.m4
@@ -1,5 +1,5 @@
-# fseek.m4 serial 1
-dnl Copyright (C) 2007 Free Software Foundation, Inc.
+# fseek.m4 serial 2
+dnl Copyright (C) 2007, 2009 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.
@@ -9,8 +9,12 @@ AC_DEFUN([gl_FUNC_FSEEK],
   AC_REQUIRE([gl_STDIO_H_DEFAULTS])
   AC_REQUIRE([gl_FUNC_FSEEKO])
   dnl When fseeko needs fixes, fseek needs them too.
-  if test $REPLACE_FSEEKO != 0; then
-    AC_LIBOBJ([fseek])
-    REPLACE_FSEEK=1
-  fi
+  dnl gl_FUNC_FSEEKO takes care of calling gl_REPLACE_FSEEK
+])
+
+AC_DEFUN([gl_REPLACE_FSEEK],
+[
+  AC_LIBOBJ([fseek])
+  AC_REQUIRE([gl_STDIO_H_DEFAULTS])
+  REPLACE_FSEEK=1
 ])

diff --git a/m4/fseeko.m4 b/m4/fseeko.m4
index 3d773656886d4f9811ee80be0fe07a37f347a9c9..c9fbfb7fcd19fbbbc297b9b30a0e572bcbb8f881 100644 (file)
--- a/m4/fseeko.m4
+++ b/m4/fseeko.m4
@@ -1,5 +1,5 @@
-# fseeko.m4 serial 4
-dnl Copyright (C) 2007-2008 Free Software Foundation, Inc.
+# fseeko.m4 serial 5
+dnl Copyright (C) 2007-2009 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.
@@ -15,7 +15,7 @@ AC_DEFUN([gl_FUNC_FSEEKO],
 
   AC_CACHE_CHECK([for fseeko], [gl_cv_func_fseeko],
     [
-      AC_TRY_LINK([#include <stdio.h>], [fseeko (stdin, 0, 0);],
+      AC_TRY_LINK([[#include <stdio.h>]], [fseeko (stdin, 0, 0);],
        [gl_cv_func_fseeko=yes], [gl_cv_func_fseeko=no])
     ])
   if test $gl_cv_func_fseeko = no; then
@@ -31,4 +31,6 @@ AC_DEFUN([gl_REPLACE_FSEEKO],
   AC_LIBOBJ([fseeko])
   AC_REQUIRE([gl_STDIO_H_DEFAULTS])
   REPLACE_FSEEKO=1
+  dnl If we are also using the fseek module, then fseek needs replacing, too.
+  m4_ifdef([gl_REPLACE_FSEEK], [gl_REPLACE_FSEEK])
 ])