pybind/cephfs: add symlink and its unit test

src/pybind/cephfs.py

@@ -509,6 +509,19 @@ def stat(self, path):
                           st_atime=statbuf.st_atime, st_mtime=statbuf.st_mtime,
                           st_ctime=statbuf.st_ctime)
 
+    def symlink(self, existing, newname):
+        if not isinstance(existing, str):
+            raise TypeError('existing must be a string')
+        if not isinstance(newname, str):
+            raise TypeError('newname must be a string')
+        self.require_state("mounted")
+        ret = self.libcephfs.ceph_symlink(
+            self.cluster,
+            c_char_p(existing),
+            c_char_p(newname))
+        if ret < 0:
+            raise make_ex(ret, "error in symlink")
+
     def unlink(self, path):
         self.require_state("mounted")
         ret = self.libcephfs.ceph_unlink(

src/test/pybind/test_cephfs.py

@@ -81,3 +81,19 @@ def test_open():
     cephfs.close(fd)
     assert_raises(libcephfs.OperationNotSupported, cephfs.open, 'file-1', 'a')
     cephfs.unlink('file-1')
+
+def test_symlink():
+    fd = cephfs.open('file-1', 'w')
+    cephfs.write(fd, "1111", 0)
+    cephfs.close(fd)
+    cephfs.symlink('file-1', 'file-2')
+    fd = cephfs.open('file-2', 'r')
+    assert_equal(cephfs.read(fd, 0, 4), "1111")
+    cephfs.close(fd)
+    fd = cephfs.open('file-2', 'r+')
+    cephfs.write(fd, "2222", 4)
+    cephfs.close(fd)
+    fd = cephfs.open('file-1', 'r')
+    assert_equal(cephfs.read(fd, 0, 8), "11112222")
+    cephfs.close(fd)
+    cephfs.unlink('file-2')