[PATCH 1/5] support: Add xfchdir

[Florian Weimer]

---
 support/Makefile  |  1 +
 support/xfchdir.c | 28 ++++++++++++++++++++++++++++
 support/xunistd.h |  2 ++
 3 files changed, 31 insertions(+)
 create mode 100644 support/xfchdir.c

diff --git a/support/Makefile b/support/Makefile
index a7b1b39782..93d9735135 100644
--- a/support/Makefile
+++ b/support/Makefile
@@ -132,6 +132,7 @@ libsupport-routines = \
   xdlmopen \
   xdup \
   xdup2 \
+  xfchdir \
   xfchmod \
   xfclose \
   xfdopendir \
diff --git a/support/xfchdir.c b/support/xfchdir.c
new file mode 100644
index 0000000000..577233d6c8
--- /dev/null
+++ b/support/xfchdir.c
@@ -0,0 +1,28 @@
+/* fchdir with error checking.
+   Copyright (C) 2025 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <support/check.h>
+#include <support/xunistd.h>
+#include <sys/stat.h>
+
+void
+xfchdir (int fd)
+{
+  if (fchdir (fd) != 0)
+    FAIL_EXIT1 ("fchdir (%d): %m", fd);
+}
diff --git a/support/xunistd.h b/support/xunistd.h
index 55afa4362b..8f6dd4fd1d 100644
--- a/support/xunistd.h
+++ b/support/xunistd.h
@@ -53,6 +53,8 @@ void support_check_stat_path (const char *name, const char *path, int result);
   (support_check_stat_path ("lstat64", (path), lstat64 ((path), (st))))
 void xstatx (int, const char *, int, unsigned int, struct statx *);
 void xmkdir (const char *path, mode_t);
+void xchdir (const char *path);
+void xfchdir (int);
 void xchroot (const char *path);
 void xunlink (const char *path);
 long xsysconf (int name);
-- 
2.52.0