Hi,
The documented open() bug on Solaris [7-9] and HP-UX 11.00 exists also as a
bug in fopen(). I'm applying this to fix it:
2008-08-30 Bruno Haible <[EMAIL PROTECTED]>
* m4/fopen.m4 (gl_FUNC_FOPEN): Test against bug with trailing slash.
Code copied from m4/open.m4.
* lib/fopen.c (rpl_fopen): Return NULL if the mode specifies write
access and the filename ends in a slash. Code copied from lib/open.c.
* doc/posix-functions/fopen.texi: Document bug with trailing slash.
* tests/test-fopen.c (main): Check against bug with trailing slash.
*** doc/posix-functions/fopen.texi.orig 2008-08-30 14:37:20.000000000 +0200
--- doc/posix-functions/fopen.texi 2008-08-30 14:18:12.000000000 +0200
***************
*** 9,14 ****
--- 9,18 ----
Portability problems fixed by Gnulib:
@itemize
@item
+ This function does not fail when the file name argument ends in a slash
+ and (without the slash) names a nonexistent file, on some platforms:
+ HP-UX 11.00, Solaris 9.
+ @item
On Windows platforms (excluding Cygwin), this function does usually not
recognize the @file{/dev/null} filename.
@end itemize
*** lib/fopen.c.orig 2008-08-30 14:37:20.000000000 +0200
--- lib/fopen.c 2008-08-30 14:25:06.000000000 +0200
***************
*** 1,5 ****
/* Open a stream to a file.
! 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
--- 1,5 ----
/* Open a stream to a file.
! Copyright (C) 2007-2008 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
***************
*** 21,32 ****
--- 21,61 ----
/* Specification. */
#include <stdio.h>
+ #include <errno.h>
#include <string.h>
FILE *
rpl_fopen (const char *filename, const char *mode)
#undef fopen
{
+ #if FOPEN_TRAILING_SLASH_BUG
+ /* If the filename ends in a slash and a mode that requires write access is
+ specified, then fail.
+ Rationale: POSIX
<http://www.opengroup.org/susv3/basedefs/xbd_chap04.html>
+ says that
+ "A pathname that contains at least one non-slash character and that
+ ends with one or more trailing slashes shall be resolved as if a
+ single dot character ( '.' ) were appended to the pathname."
+ and
+ "The special filename dot shall refer to the directory specified by
+ its predecessor."
+ If the named file already exists as a directory, then if a mode that
+ requires write access is specified, fopen() must fail because POSIX
+ <http://www.opengroup.org/susv3/functions/fopen.html> says that it
+ fails with errno = EISDIR in this case.
+ If the named file does not exist or does not name a directory, then
+ fopen() must fail since the file does not contain a '.' directory. */
+ if (mode[0] == 'w' || mode[0] == 'a')
+ {
+ size_t len = strlen (filename);
+ if (len > 0 && filename[len - 1] == '/')
+ {
+ errno = EISDIR;
+ return NULL;
+ }
+ }
+ #endif
+
#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
if (strcmp (filename, "/dev/null") == 0)
filename = "NUL";
*** m4/fopen.m4.orig 2008-08-30 14:37:20.000000000 +0200
--- m4/fopen.m4 2008-08-30 14:17:43.000000000 +0200
***************
*** 1,5 ****
! # fopen.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.
--- 1,5 ----
! # fopen.m4 serial 2
! dnl Copyright (C) 2007-2008 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
***************
*** 13,17 ****
--- 13,50 ----
REPLACE_FOPEN=1
AC_LIBOBJ([fopen])
;;
+ *)
+ dnl fopen("foo/", "w") should not create a file when the file name has a
+ dnl trailing slash.
+ AC_CACHE_CHECK([whether fopen recognizes a trailing slash],
+ [gl_cv_func_fopen_slash],
+ [
+ AC_TRY_RUN([
+ #include <stddef.h>
+ #include <stdio.h>
+ int main ()
+ {
+ return fopen ("conftest.sl/", "w") != NULL;
+ }], [gl_cv_func_fopen_slash=yes], [gl_cv_func_fopen_slash=no],
+ [
+ changequote(,)dnl
+ case "$host_os" in
+ solaris2.[0-9]*) gl_cv_func_fopen_slash="guessing no" ;;
+ hpux*) gl_cv_func_fopen_slash="guessing no" ;;
+ *) gl_cv_func_fopen_slash="guessing yes" ;;
+ esac
+ changequote([,])dnl
+ ])
+ rm -f conftest.sl
+ ])
+ case "$gl_cv_func_fopen_slash" in
+ *no)
+ AC_DEFINE([FOPEN_TRAILING_SLASH_BUG], 1,
+ [Define to 1 if fopen() fails to recognize a trailing slash.])
+ REPLACE_FOPEN=1
+ AC_LIBOBJ([fopen])
+ ;;
+ esac
+ ;;
esac
])
*** tests/test-fopen.c.orig 2008-08-30 14:37:20.000000000 +0200
--- tests/test-fopen.c 2008-08-30 14:33:10.000000000 +0200
***************
*** 36,41 ****
--- 36,43 ----
int
main ()
{
+ ASSERT (fopen ("nonexist.ent/", "w") == NULL);
+
ASSERT (fopen ("/dev/null", "r") != NULL);
return 0;
