# getcwd.m4 - check for working getcwd that is compatible with glibc
-# Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007, 2009, 2010 Free Software
-# Foundation, Inc.
+# Copyright (C) 2001, 2003-2007, 2009-2011 Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
# Written by Paul Eggert.
-# serial 2
+# serial 6
AC_DEFUN([gl_FUNC_GETCWD_NULL],
[
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
AC_CACHE_CHECK([whether getcwd (NULL, 0) allocates memory for result],
[gl_cv_func_getcwd_null],
[AC_RUN_IFELSE([AC_LANG_PROGRAM([[
# endif
]], [[
#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-/* mingw cwd does not start with '/', but getcwd does allocate. */
+/* mingw cwd does not start with '/', but getcwd does allocate.
+ However, mingw fails to honor non-zero size. */
#else
if (chdir ("/") != 0)
return 1;
else
{
char *f = getcwd (NULL, 0);
- return ! (f && f[0] == '/' && !f[1]);
+ if (! f)
+ return 2;
+ if (f[0] != '/')
+ return 3;
+ if (f[1] != '\0')
+ return 4;
+ return 0;
}
#endif
+ /* If size is non-zero, allocation must fail if size is too small */
+ if (getcwd (NULL, 1))
+ return 5;
]])],
[gl_cv_func_getcwd_null=yes],
[gl_cv_func_getcwd_null=no],
*-gnu*) gl_cv_func_getcwd_null="guessing yes";;
# Guess yes on Cygwin.
cygwin*) gl_cv_func_getcwd_null="guessing yes";;
- # Guess yes on mingw.
- mingw*) gl_cv_func_getcwd_null="guessing yes";;
# If we don't know, assume the worst.
*) gl_cv_func_getcwd_null="guessing no";;
esac
]])])
])
+
+dnl Guarantee that getcwd will malloc with a NULL first argument. Assumes
+dnl that either the system getcwd is robust, or that calling code is okay
+dnl with spurious failures when run from a directory with an absolute name
+dnl larger than 4k bytes.
+dnl
+dnl Assumes that getcwd exists; if you are worried about obsolete
+dnl platforms that lacked getcwd(), then you need to use the GPL module.
+AC_DEFUN([gl_FUNC_GETCWD_LGPL],
+[
+ AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+ AC_REQUIRE([gl_FUNC_GETCWD_NULL])
+
+ case $gl_cv_func_getcwd_null in
+ *yes) ;;
+ *)
+ dnl Minimal replacement
+ REPLACE_GETCWD=1
+ AC_LIBOBJ([getcwd-lgpl])
+ ;;
+ esac
+])
+
+dnl Check for all known getcwd bugs; useful for a program likely to be
+dnl executed from an arbitrary location.
AC_DEFUN([gl_FUNC_GETCWD],
[
AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
case $gl_cv_func_getcwd_null,$gl_cv_func_getcwd_path_max,$gl_abort_bug in
*yes,yes,no) ;;
*)
+ dnl Full replacement, overrides LGPL replacement.
REPLACE_GETCWD=1
AC_LIBOBJ([getcwd])
gl_PREREQ_GETCWD;;
esac
])
-# Prerequisites of lib/getcwd.c.
+# Prerequisites of lib/getcwd.c, when full replacement is in effect.
AC_DEFUN([gl_PREREQ_GETCWD],
[
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])