1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 // UdevLinux listens for device change notifications from udev and runs
6 // callbacks when notifications occur.
8 // UdevLinux must be created on a MessageLoop of TYPE_IO.
9 // UdevLinux is not thread-safe.
18 // std::vector<UdevLinux::UdevMonitorFilter> filters;
19 // filters.push_back(content::UdevLinux::UdevMonitorFilter("block", NULL));
20 // udev_.reset(new UdevLinux(filters,
21 // base::Bind(&Foo::Notify, this)));
24 // // Called when a "block" device attaches/detaches.
25 // // To hold on to |device|, call udev_device_ref(device).
26 // void Notify(udev_device* device) {
27 // // Do something with |device|.
31 // scoped_ptr<UdevLinux> udev_;
33 // DISALLOW_COPY_AND_ASSIGN(Foo);
36 #ifndef CONTENT_BROWSER_UDEV_LINUX_H_
37 #define CONTENT_BROWSER_UDEV_LINUX_H_
41 #include "base/basictypes.h"
42 #include "base/callback.h"
43 #include "base/compiler_specific.h"
44 #include "base/message_loop/message_pump_libevent.h"
45 #include "device/udev_linux/scoped_udev.h"
55 class UdevLinux : public base::MessagePumpLibevent::Watcher {
57 typedef base::Callback<void(udev_device*)> UdevNotificationCallback;
59 // subsystem and devtype parameter for
60 // udev_monitor_filter_add_match_subsystem_devtype().
61 struct UdevMonitorFilter {
62 UdevMonitorFilter(const char* subsystem_in, const char* devtype_in)
63 : subsystem(subsystem_in),
66 const char* subsystem;
70 // Filter incoming devices based on |filters|.
71 // Calls |callback| upon device change events.
72 UdevLinux(const std::vector<UdevMonitorFilter>& filters,
73 const UdevNotificationCallback& callback);
74 ~UdevLinux() override;
76 // Returns the udev handle to be passed into other udev_*() functions.
80 // base::MessagePump:Libevent::Watcher implementation.
81 void OnFileCanReadWithoutBlocking(int fd) override;
82 void OnFileCanWriteWithoutBlocking(int fd) override;
84 // libudev-related items, the main context, and the monitoring context to be
85 // notified about changes to device states.
86 device::ScopedUdevPtr udev_;
87 device::ScopedUdevMonitorPtr monitor_;
89 base::MessagePumpLibevent::FileDescriptorWatcher monitor_watcher_;
90 UdevNotificationCallback callback_;
92 DISALLOW_COPY_AND_ASSIGN(UdevLinux);
95 } // namespace content
97 #endif // CONTENT_BROWSER_UDEV_LINUX_H_