replace: Check if we have mremap() available

1 files changed, 48 insertions, 0 deletions

diff --git a/lib/replace/test/shared_mremap.c b/lib/replace/test/shared_mremap.c
new file mode 100644
index 0000000000..05032ad12e
--- /dev/null
+++ b/lib/replace/test/shared_mremap.c
@@ -0,0 +1,48 @@
+/* this tests whether we can use mremap */
+
+#if defined(HAVE_UNISTD_H)
+#include <unistd.h>
+#endif
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#define DATA "conftest.mmap"
+
+#ifndef MAP_FILE
+#define MAP_FILE 0
+#endif
+
+#ifndef MAP_FAILED
+#define MAP_FAILED (int *)-1
+#endif
+
+main()
+{
+	int *buf;
+	int fd;
+	int err = 1;
+
+	fd = open(DATA, O_RDWR|O_CREAT|O_TRUNC, 0666);
+	if (fd == -1) {
+		exit(1);
+	}
+
+	buf = (int *)mmap(NULL, 0x1000, PROT_READ | PROT_WRITE,
+			  MAP_FILE | MAP_SHARED, fd, 0);
+	if (buf == MAP_FAILED) {
+		goto done;
+	}
+
+	buf = mremap(buf, 0x1000, 0x2000, MREMAP_MAYMOVE);
+	if (buf == MAP_FAILED) {
+		goto done;
+	}
+
+	err = 0;
+done:
+	close(fd);
+	unlink(DATA);
+	exit(err);
+}