[email protected] | 1666bf2 | 2012-07-27 02:03:17 | [diff] [blame] | 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. |
| 4 | |
| 5 | // UdevLinux listens for device change notifications from udev and runs |
| 6 | // callbacks when notifications occur. |
| 7 | // |
| 8 | // UdevLinux must be created on a MessageLoop of TYPE_IO. |
| 9 | // UdevLinux is not thread-safe. |
| 10 | // |
| 11 | // Example usage: |
| 12 | // |
| 13 | // class UdevLinux; |
| 14 | // |
| 15 | // class Foo { |
| 16 | // public: |
| 17 | // Foo() { |
| 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))); |
| 22 | // } |
| 23 | // |
| 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|. |
| 28 | // } |
| 29 | // |
| 30 | // private: |
| 31 | // scoped_ptr<UdevLinux> udev_; |
| 32 | // |
| 33 | // DISALLOW_COPY_AND_ASSIGN(Foo); |
| 34 | // }; |
| 35 | |
| 36 | #ifndef CONTENT_BROWSER_UDEV_LINUX_H_ |
| 37 | #define CONTENT_BROWSER_UDEV_LINUX_H_ |
| 38 | |
| 39 | #include <vector> |
| 40 | |
| 41 | #include "base/basictypes.h" |
| 42 | #include "base/callback.h" |
| 43 | #include "base/compiler_specific.h" |
| 44 | #include "base/message_pump_libevent.h" |
| 45 | |
| 46 | extern "C" { |
| 47 | struct udev; |
| 48 | struct udev_device; |
| 49 | struct udev_monitor; |
| 50 | } |
| 51 | |
| 52 | namespace content { |
| 53 | |
| 54 | class UdevLinux : public base::MessagePumpLibevent::Watcher { |
| 55 | public: |
| 56 | typedef base::Callback<void(udev_device*)> UdevNotificationCallback; |
| 57 | |
| 58 | // subsystem and devtype parameter for |
| 59 | // udev_monitor_filter_add_match_subsystem_devtype(). |
| 60 | struct UdevMonitorFilter { |
| 61 | UdevMonitorFilter(const char* subsystem_in, const char* devtype_in) |
| 62 | : subsystem(subsystem_in), |
| 63 | devtype(devtype_in) { |
| 64 | } |
| 65 | const char* subsystem; |
| 66 | const char* devtype; |
| 67 | }; |
| 68 | |
| 69 | // Filter incoming devices based on |filters|. |
| 70 | // Calls |callback| upon device change events. |
| 71 | UdevLinux(const std::vector<UdevMonitorFilter>& filters, |
| 72 | const UdevNotificationCallback& callback); |
| 73 | virtual ~UdevLinux(); |
| 74 | |
| 75 | |
| 76 | // Returns the udev handle to be passed into other udev_*() functions. |
| 77 | udev* udev_handle(); |
| 78 | |
| 79 | private: |
| 80 | // base::MessagePump:Libevent::Watcher implementation. |
| 81 | virtual void OnFileCanReadWithoutBlocking(int fd) OVERRIDE; |
| 82 | virtual void OnFileCanWriteWithoutBlocking(int fd) OVERRIDE; |
| 83 | |
| 84 | // libudev-related items, the main context, and the monitoring context to be |
| 85 | // notified about changes to device states. |
| 86 | udev* udev_; |
| 87 | udev_monitor* monitor_; |
| 88 | int monitor_fd_; |
| 89 | base::MessagePumpLibevent::FileDescriptorWatcher monitor_watcher_; |
| 90 | UdevNotificationCallback callback_; |
| 91 | |
| 92 | DISALLOW_COPY_AND_ASSIGN(UdevLinux); |
| 93 | }; |
| 94 | |
| 95 | } // namespace content |
| 96 | |
| 97 | #endif // CONTENT_BROWSER_UDEV_LINUX_H_ |