1 files changed, 43 insertions, 0 deletions
diff --git a/lib/fadvise.c b/lib/fadvise.c
new file mode 100644
index 0000000..79e6ac7
--- /dev/null
+++ b/lib/fadvise.c
@@ -0,0 +1,43 @@
+/* Declare an access pattern hint for files.
+   Copyright (C) 2010-2023 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/>.  */
+
+/* Without this pragma, gcc suggests that (given !HAVE_POSIX_FADVISE)
+   the fdadvise function might be a candidate for attribute 'const'.  */
+#if (__GNUC__ == 4 && 6 <= __GNUC_MINOR__) || 4 < __GNUC__
+# pragma GCC diagnostic ignored "-Wsuggest-attribute=const"
+#endif
+
+#include <config.h>
+#include "fadvise.h"
+
+#include <stdio.h>
+#include <fcntl.h>
+#include "ignore-value.h"
+
+void
+fdadvise (int fd, off_t offset, off_t len, fadvice_t advice)
+{
+#if HAVE_POSIX_FADVISE
+  ignore_value (posix_fadvise (fd, offset, len, advice));
+#endif
+}
+
+void
+fadvise (FILE *fp, fadvice_t advice)
+{
+  if (fp)
+    fdadvise (fileno (fp), 0, 0, advice);
+}