1 files changed, 96 insertions, 0 deletions
diff --git a/lib/mkfifoat.c b/lib/mkfifoat.c
new file mode 100644
index 0000000..23243e8
--- /dev/null
+++ b/lib/mkfifoat.c
@@ -0,0 +1,96 @@
+/* Create a named fifo relative to an open directory.
+   Copyright (C) 2009-2023 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
+   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, see <https://www.gnu.org/licenses/>.  */
+
+/* written by Eric Blake */
+
+#include <config.h>
+
+/* Specification.  */
+#include <sys/stat.h>
+
+#include <stdlib.h>
+
+#if HAVE_MKFIFOAT
+
+# include <errno.h>
+# include <fcntl.h>
+# include <string.h>
+
+int
+rpl_mkfifoat (int fd, char const *file, mode_t mode)
+#undef mkfifoat
+{
+  /* Use the original mkfifoat(), but correct the trailing slash handling.  */
+  size_t len = strlen (file);
+  if (len && file[len - 1] == '/')
+    {
+      struct stat st;
+
+      if (fstatat (fd, file, &st, AT_SYMLINK_NOFOLLOW) < 0)
+        {
+          if (errno == EOVERFLOW)
+            /* It's surely a file, not a directory.  */
+            errno = ENOTDIR;
+        }
+      else
+        {
+          /* It's a directory, otherwise fstatat() would have reported an error
+             ENOTDIR.  */
+          errno = EEXIST;
+        }
+      return -1;
+    }
+
+  return mkfifoat (fd, file, mode);
+}
+
+#else
+
+# if !HAVE_MKFIFO
+
+#  include <errno.h>
+
+/* Mingw lacks mkfifo, so this wrapper is trivial.  */
+
+int
+mkfifoat (_GL_UNUSED int fd, _GL_UNUSED char const *path,
+          _GL_UNUSED mode_t mode)
+{
+  errno = ENOSYS;
+  return -1;
+}
+
+# else /* HAVE_MKFIFO */
+
+/* Create a named fifo FILE relative to directory FD, with access
+   permissions in MODE.  If possible, do it without changing the
+   working directory.  Otherwise, resort to using save_cwd/fchdir,
+   then mkfifo/restore_cwd.  If either the save_cwd or the restore_cwd
+   fails, then give a diagnostic and exit nonzero.  */
+
+#  define AT_FUNC_NAME mkfifoat
+#  define AT_FUNC_F1 mkfifo
+#  define AT_FUNC_POST_FILE_PARAM_DECLS , mode_t mode
+#  define AT_FUNC_POST_FILE_ARGS        , mode
+#  include "at-func.c"
+#  undef AT_FUNC_NAME
+#  undef AT_FUNC_F1
+#  undef AT_FUNC_POST_FILE_PARAM_DECLS
+#  undef AT_FUNC_POST_FILE_ARGS
+
+# endif /* HAVE_MKFIFO */
+
+#endif /* HAVE_MKFIFOAT */