common: add infrastructure for renameat2 syscall tests

The renameat2() syscall was merged into 3.15-rc (merge commit:
7df934526c0b).

This adds the shared infrastructure for the actual test scripts.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 102 insertions, 0 deletions

diff --git a/src/renameat2.c b/src/renameat2.c
new file mode 100644
index 00000000..51459597
--- /dev/null
+++ b/src/renameat2.c
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2014, Miklos Szeredi <mszeredi@suse.cz>
+ * This file is published under GPL2+.
+ *
+ * This is a trivial wrapper around the renameat2 syscall.
+ */
+
+#include "global.h"
+
+#ifndef HAVE_RENAMEAT2
+#include <sys/syscall.h>
+
+#if !defined(SYS_renameat2) && defined(__x86_64__)
+#define SYS_renameat2 316
+#endif
+
+static int renameat2(int dfd1, const char *path1,
+		     int dfd2, const char *path2,
+		     unsigned int flags)
+{
+#ifdef SYS_renameat2
+	return syscall(SYS_renameat2, dfd1, path1, dfd2, path2, flags);
+#else
+	errno = ENOSYS;
+	return -1;
+#endif
+}
+#endif
+
+#ifndef RENAME_NOREPLACE
+#define RENAME_NOREPLACE	(1 << 0)	/* Don't overwrite target */
+#endif
+#ifndef RENAME_EXCHANGE
+#define RENAME_EXCHANGE		(1 << 1)	/* Exchange source and dest */
+#endif
+#ifndef RENAME_WHITEOUT
+#define RENAME_WHITEOUT		(1 << 2)	/* Whiteout source */
+#endif
+
+int main(int argc, char *argv[])
+{
+	int ret;
+	int c;
+	const char *path1 = NULL;
+	const char *path2 = NULL;
+	unsigned int flags = 0;
+	int test = 0;
+
+	for (c = 1; c < argc; c++) {
+		if (argv[c][0] == '-') {
+			switch (argv[c][1]) {
+			case 't':
+				test = 1;
+				break;
+			case 'n':
+				flags |= RENAME_NOREPLACE;
+				break;
+			case 'x':
+				flags |= RENAME_EXCHANGE;
+				break;
+			case 'w':
+				flags |= RENAME_WHITEOUT;
+				break;
+			default:
+				goto usage;
+			}
+		} else if (!path1) {
+			path1 = argv[c];
+		} else if (!path2) {
+			path2 = argv[c];
+		} else {
+			goto usage;
+		}
+	}
+
+	if (!test && (!path1 || !path2))
+		goto usage;
+
+	ret = renameat2(AT_FDCWD, path1, AT_FDCWD, path2, flags);
+	if (ret == -1) {
+		if (test) {
+			if (errno == ENOSYS || errno == EINVAL)
+				return 1;
+			else
+				return 0;
+		}
+		perror("");
+		return 1;
+	}
+
+	return 0;
+
+usage:
+	fprintf(stderr,
+		"usage: %s [-t] [-n|-x|-w] path1 path2\n"
+		"  -t  test\n"
+		"  -n  noreplace\n"
+		"  -x  exchange\n"
+		"  -w  whiteout\n", argv[0]);
+
+	return 1;
+}