1 // Copyright 2021 The Chromium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_TEST_SCOPED_DEV_ZERO_FUCHSIA_H_ 6 #define BASE_TEST_SCOPED_DEV_ZERO_FUCHSIA_H_ 7 8 #include <lib/fdio/namespace.h> 9 10 #include "base/memory/ref_counted.h" 11 #include "base/memory/scoped_refptr.h" 12 #include "base/threading/sequence_bound.h" 13 #include "base/threading/thread.h" 14 15 namespace base { 16 17 // An object that causes /dev/zero to exist during its lifetime. A reference to 18 // this class may be held by tests that require access to /dev/zero for the 19 // lifetime of that need. 20 class ScopedDevZero final : public RefCounted<ScopedDevZero> { 21 public: 22 REQUIRE_ADOPTION_FOR_REFCOUNTED_TYPE(); 23 24 // Returns a reference to the process-global /dev/zero. This must only be 25 // called, and the returned reference released, on the main thread. Returns 26 // null in case of failure to create the instance. It is good practice for 27 // tests to ASSERT the returned pointer. 28 static scoped_refptr<ScopedDevZero> Get(); 29 30 ScopedDevZero(const ScopedDevZero&) = delete; 31 ScopedDevZero operator=(const ScopedDevZero&) = delete; 32 33 private: 34 friend class RefCounted<ScopedDevZero>; 35 class Server; 36 37 ScopedDevZero(); 38 ~ScopedDevZero(); 39 40 // Spins off the server thread and binds its pesudo-dir to /dev, returning 41 // true if all goes well, or false in case of any error. 42 bool Initialize(); 43 44 // A raw pointer to the process's single instance. Multiple references to this 45 // instance may be handed out to consumers. 46 static ScopedDevZero* instance_; 47 Thread io_thread_; 48 fdio_ns_t* global_namespace_ = nullptr; 49 SequenceBound<Server> server_; 50 }; 51 52 } // namespace base 53 54 #endif // BASE_TEST_SCOPED_DEV_ZERO_FUCHSIA_H_ 55