rawmemchr: relax license

[gnulib.git] / lib / getcwd.c

diff --git a/lib/getcwd.c b/lib/getcwd.c
index f8567bd..6658ed5 100644 (file)
--- a/lib/getcwd.c
+++ b/lib/getcwd.c
@@ -1,25 +1,22 @@
-/* Copyright (C) 1991,92,93,94,95,96,97,98,99,2004,2005,2006,2007 Free Software
-   Foundation, Inc.
+/* Copyright (C) 1991-1999, 2004-2009 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
-   This program is free software; you can redistribute it and/or modify
+   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
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
 
-   You should have received a copy of the GNU General Public License along
-   with this program; if not, write to the Free Software Foundation,
-   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #if !_LIBC
 # include <config.h>
 # include <unistd.h>
-# include "dirfd.h"
 #endif
 
 #include <errno.h>
@@ -30,6 +27,14 @@
 
 #include <fcntl.h> /* For AT_FDCWD on Solaris 9.  */
 
+/* If this host provides the openat function, then enable
+   code below to make getcwd more efficient and robust.  */
+#ifdef HAVE_OPENAT
+# define HAVE_OPENAT_SUPPORT 1
+#else
+# define HAVE_OPENAT_SUPPORT 0
+#endif
+
 #ifndef __set_errno
 # define __set_errno(val) (errno = (val))
 #endif
@@ -54,20 +59,6 @@
 
 #include <limits.h>
 
-/* Work around a bug in Solaris 9 and 10: AT_FDCWD is positive.  Its
-   value exceeds INT_MAX, so its use as an int doesn't conform to the
-   C standard, and GCC and Sun C complain in some cases.  */
-#if 0 < AT_FDCWD && AT_FDCWD == 0xffd19553
-# undef AT_FDCWD
-# define AT_FDCWD (-3041965)
-#endif
-
-#ifdef ENAMETOOLONG
-# define is_ENAMETOOLONG(x) ((x) == ENAMETOOLONG)
-#else
-# define is_ENAMETOOLONG(x) 0
-#endif
-
 #ifndef MAX
 # define MAX(a, b) ((a) < (b) ? (b) : (a))
 #endif
@@ -90,7 +81,7 @@
 #endif
 
 #if !_LIBC
-# define __getcwd getcwd
+# define __getcwd rpl_getcwd
 # define __lstat lstat
 # define __closedir closedir
 # define __opendir opendir
@@ -98,7 +89,11 @@
 #endif
 
 /* The results of opendir() in this file are not used with dirfd and fchdir,
-   therefore save some unnecessary recursion in fchdir.c.  */
+   and we do not leak fds to any single-threaded code that could use stdio,
+   therefore save some unnecessary recursion in fchdir.c.
+   FIXME - if the kernel ever adds support for multi-thread safety for
+   avoiding standard fds, then we should use opendir_safer and
+   openat_safer.  */
 #undef opendir
 #undef closedir
 \f
@@ -123,7 +118,7 @@ __getcwd (char *buf, size_t size)
       DEEP_NESTING = 100
     };
 
-#ifdef AT_FDCWD
+#if HAVE_OPENAT_SUPPORT
   int fd = AT_FDCWD;
   bool fd_needs_closing = false;
 #else
@@ -155,7 +150,7 @@ __getcwd (char *buf, size_t size)
 
 # undef getcwd
   dir = getcwd (buf, size);
-  if (dir || (errno != ERANGE && !is_ENAMETOOLONG (errno) && errno != ENOENT))
+  if (dir || (errno != ERANGE && errno != ENAMETOOLONG && errno != ENOENT))
     return dir;
 #endif
 
@@ -204,7 +199,7 @@ __getcwd (char *buf, size_t size)
       bool use_d_ino = true;
 
       /* Look at the parent directory.  */
-#ifdef AT_FDCWD
+#if HAVE_OPENAT_SUPPORT
       fd = openat (fd, "..", O_RDONLY);
       if (fd < 0)
        goto lose;
@@ -231,7 +226,7 @@ __getcwd (char *buf, size_t size)
       mount_point = dotdev != thisdev;
 
       /* Search for the last directory.  */
-#ifdef AT_FDCWD
+#if HAVE_OPENAT_SUPPORT
       dirstream = fdopendir (fd);
       if (dirstream == NULL)
        goto lose;
@@ -287,7 +282,7 @@ __getcwd (char *buf, size_t size)
 
          {
            int entry_status;
-#ifdef AT_FDCWD
+#if HAVE_OPENAT_SUPPORT
            entry_status = fstatat (fd, d->d_name, &st, AT_SYMLINK_NOFOLLOW);
 #else
            /* Compute size needed for this file name, or for the file
@@ -383,7 +378,7 @@ __getcwd (char *buf, size_t size)
   if (dirp == &dir[allocated - 1])
     *--dirp = '/';
 
-#ifndef AT_FDCWD
+#if ! HAVE_OPENAT_SUPPORT
   if (dotlist != dots)
     free (dotlist);
 #endif
@@ -391,7 +386,7 @@ __getcwd (char *buf, size_t size)
   used = dir + allocated - dirp;
   memmove (dir, dirp, used);
 
-  if (buf == NULL && size == 0)
+  if (size == 0)
     /* Ensure that the buffer is only as large as necessary.  */
     buf = realloc (dir, used);
 
@@ -409,7 +404,7 @@ __getcwd (char *buf, size_t size)
     int save = errno;
     if (dirstream)
       __closedir (dirstream);
-#ifdef AT_FDCWD
+#if HAVE_OPENAT_SUPPORT
     if (fd_needs_closing)
       close (fd);
 #else