3 files changed, 125 insertions, 0 deletions
diff --git a/test/fuse/linux/BUILD b/test/fuse/linux/BUILD
index cc5bd560e..eb090cbfd 100644
--- a/test/fuse/linux/BUILD
+++ b/test/fuse/linux/BUILD
@@ -141,6 +141,21 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "fuse_fd_util",
+    testonly = 1,
+    srcs = ["fuse_fd_util.cc"],
+    hdrs = ["fuse_fd_util.h"],
+    deps = [
+        gtest,
+        ":fuse_base",
+        "//test/util:cleanup",
+        "//test/util:file_descriptor",
+        "//test/util:fuse_util",
+        "//test/util:posix_error",
+    ],
+)
+
 cc_binary(
     name = "read_test",
     testonly = 1,
diff --git a/test/fuse/linux/fuse_fd_util.cc b/test/fuse/linux/fuse_fd_util.cc
new file mode 100644
index 000000000..4a2505b00
--- /dev/null
+++ b/test/fuse/linux/fuse_fd_util.cc
@@ -0,0 +1,62 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "test/fuse/linux/fuse_fd_util.h"
+
+#include <fcntl.h>
+#include <linux/fuse.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/uio.h>
+
+#include <string>
+#include <vector>
+
+#include "test/util/cleanup.h"
+#include "test/util/file_descriptor.h"
+#include "test/util/fuse_util.h"
+#include "test/util/posix_error.h"
+
+namespace gvisor {
+namespace testing {
+
+PosixErrorOr<FileDescriptor> FuseFdTest::OpenPath(const std::string &path,
+                                                  uint32_t flags, uint64_t fh) {
+  struct fuse_out_header out_header = {
+      .len = sizeof(struct fuse_out_header) + sizeof(struct fuse_open_out),
+  };
+  struct fuse_open_out out_payload = {
+      .fh = fh,
+      .open_flags = flags,
+  };
+  auto iov_out = FuseGenerateIovecs(out_header, out_payload);
+  SetServerResponse(FUSE_OPEN, iov_out);
+
+  auto res = Open(path.c_str(), flags);
+  if (res.ok()) {
+    SkipServerActualRequest();
+  }
+  return res;
+}
+
+Cleanup FuseFdTest::CloseFD(FileDescriptor &fd) {
+  return Cleanup([&] {
+    close(fd.release());
+    SkipServerActualRequest();
+  });
+}
+
+}  // namespace testing
+}  // namespace gvisor
+
diff --git a/test/fuse/linux/fuse_fd_util.h b/test/fuse/linux/fuse_fd_util.h
new file mode 100644
index 000000000..066185c94
--- /dev/null
+++ b/test/fuse/linux/fuse_fd_util.h
@@ -0,0 +1,48 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef GVISOR_TEST_FUSE_FUSE_FD_UTIL_H_
+#define GVISOR_TEST_FUSE_FUSE_FD_UTIL_H_
+
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <string>
+
+#include "test/fuse/linux/fuse_base.h"
+#include "test/util/cleanup.h"
+#include "test/util/file_descriptor.h"
+#include "test/util/posix_error.h"
+
+namespace gvisor {
+namespace testing {
+
+class FuseFdTest : public FuseTest {
+ public:
+  // Sets the FUSE server to respond to a FUSE_OPEN with corresponding flags and
+  // fh. Then does a real file system open on the absolute path to get an fd.
+  PosixErrorOr<FileDescriptor> OpenPath(const std::string &path,
+                                        uint32_t flags = O_RDONLY,
+                                        uint64_t fh = 1);
+
+  // Returns a cleanup object that closes the fd when it is destroyed. After
+  // the close is done, tells the FUSE server to skip this FUSE_RELEASE.
+  Cleanup CloseFD(FileDescriptor &fd);
+};
+
+}  // namespace testing
+}  // namespace gvisor
+
+#endif  // GVISOR_TEST_FUSE_FUSE_FD_UTIL_H_