blob: 6af58c86c683039603e4169e1a438c9db85d1612 [file] [log] [blame]
// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <fuchsia/io/cpp/fidl.h>
#include <lib/async/dispatcher.h>
#include <lib/zx/channel.h>
#include <stddef.h>
#include <stdint.h>
namespace vfs {
namespace internal {
class Node;
// A connection to a file system object.
// A connection manages a single zx::channel, typically to another process.
class Connection {
// Create a connection with the given |flags|.
// |flags| define permissions and rights that this connection have over
// |Node|. They are defined in || fidl for example
// |OPEN_FLAG_DESCRIBE|. These are stored in this object for future use and no
// validations are performed.
explicit Connection(uint32_t flags);
virtual ~Connection();
Connection(const Connection&) = delete;
Connection& operator=(const Connection&) = delete;
// The flags associated with this connection.
// These flags are typically received from || or
// ||.
// For example, |ZX_FS_RIGHT_READABLE|.
uint32_t flags() const { return flags_; }
// The current file offset.
// Typically used to position |read| and |write| operations. Can be adjusted
// using |lseek|.
uint64_t offset() const { return offset_; }
void set_offset(uint64_t offset) { offset_ = offset; }
// Associate |request| with this connection.
// Waits for messages asynchronously on the |request| channel using
// |dispatcher|. If |dispatcher| is |nullptr|, the implementation will call
// |async_get_default_dispatcher| to obtain the default dispatcher for the
// current thread.
// After calling internal functions from implementing classes this function
// will also send OnOpen event if |OPEN_FLAG_DESCRIBE| is present in |flags_|
// and binding is successful.
// Returns |ZX_ERR_BAD_STATE| if channel is already bound.
// Typically called during connection setup.
zx_status_t Bind(zx::channel request, async_dispatcher_t* dispatcher);
// Send OnOpen event for |fuchsia::io::Node|.
// This function will not check for |OPEN_FLAG_DESCRIBE|. Caller should do
// that. Every subclass must implement this.
// This should only be called from |Bind()|.
virtual void SendOnOpenEvent(zx_status_t status) = 0;
// Associate |request| with this connection.
// This function is called by |Connection::Bind()|.
// Waits for messages asynchronously on the |request| channel using
// |dispatcher|. If |dispatcher| is |nullptr|, the implementation will call
// |async_get_default_dispatcher| to obtain the default dispatcher for the
// current thread.
// Should returns |ZX_ERR_BAD_STATE| if channel is already bound.
virtual zx_status_t BindInternal(zx::channel request, async_dispatcher_t* dispatcher) = 0;
// Implementations for common || operations. Used by
// subclasses to avoid code duplication.
void Clone(Node* vn, uint32_t flags, zx::channel request, async_dispatcher_t* dispatcher);
void Close(Node* vn, fuchsia::io::Node::CloseCallback callback);
void Describe(Node* vn, fuchsia::io::Node::DescribeCallback callback);
void Sync(Node* vn, fuchsia::io::Node::SyncCallback callback);
void GetAttr(Node* vn, fuchsia::io::Node::GetAttrCallback callback);
void SetAttr(Node* vn, uint32_t flags, fuchsia::io::NodeAttributes attributes,
fuchsia::io::Node::SetAttrCallback callback);
// returns || if status is |ZX_OK|, else returns null
// inside unique_ptr.
std::unique_ptr<fuchsia::io::NodeInfo> NodeInfoIfStatusOk(Node* vn, zx_status_t status);
// The flags associated with this connection.
// See |flags()| for more information.
uint32_t flags_ = 0u;
// The current file offset.
// See |offset()| for more information.
uint64_t offset_ = 0u;
} // namespace internal
} // namespace vfs