1 /* 2 * libjingle 3 * Copyright 2012 Google Inc. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include "talk/media/devices/deviceinfo.h" 29 30 #include "talk/media/devices/libudevsymboltable.h" 31 #include "webrtc/base/common.h" // for ASSERT 32 33 namespace cricket { 34 35 class ScopedLibUdev { 36 public: 37 static ScopedLibUdev* Create() { 38 ScopedLibUdev* ret_val = new ScopedLibUdev(); 39 if (!ret_val->Init()) { 40 delete ret_val; 41 return NULL; 42 } 43 return ret_val; 44 } 45 ~ScopedLibUdev() { 46 libudev_.Unload(); 47 } 48 49 LibUDevSymbolTable* instance() { return &libudev_; } 50 51 private: 52 ScopedLibUdev() {} 53 54 bool Init() { 55 return libudev_.Load() && 56 !IsWrongLibUDevAbiVersion(libudev_.GetDllHandle()); 57 } 58 59 LibUDevSymbolTable libudev_; 60 }; 61 62 class ScopedUdev { 63 public: 64 explicit ScopedUdev(LibUDevSymbolTable* libudev) : libudev_(libudev) { 65 udev_ = libudev_->udev_new()(); 66 } 67 ~ScopedUdev() { 68 if (udev_) libudev_->udev_unref()(udev_); 69 } 70 71 udev* instance() { return udev_; } 72 73 private: 74 LibUDevSymbolTable* libudev_; 75 udev* udev_; 76 }; 77 78 class ScopedUdevEnumerate { 79 public: 80 ScopedUdevEnumerate(LibUDevSymbolTable* libudev, udev* udev) 81 : libudev_(libudev) { 82 enumerate_ = libudev_->udev_enumerate_new()(udev); 83 } 84 ~ScopedUdevEnumerate() { 85 if (enumerate_) libudev_->udev_enumerate_unref()(enumerate_); 86 } 87 88 udev_enumerate* instance() { return enumerate_; } 89 90 private: 91 LibUDevSymbolTable* libudev_; 92 udev_enumerate* enumerate_; 93 }; 94 95 bool GetUsbProperty(const Device& device, const char* property_name, 96 std::string* property) { 97 rtc::scoped_ptr<ScopedLibUdev> libudev_context(ScopedLibUdev::Create()); 98 if (!libudev_context) { 99 return false; 100 } 101 ScopedUdev udev_context(libudev_context->instance()); 102 if (!udev_context.instance()) { 103 return false; 104 } 105 ScopedUdevEnumerate enumerate_context(libudev_context->instance(), 106 udev_context.instance()); 107 if (!enumerate_context.instance()) { 108 return false; 109 } 110 libudev_context->instance()->udev_enumerate_add_match_subsystem()( 111 enumerate_context.instance(), "video4linux"); 112 libudev_context->instance()->udev_enumerate_scan_devices()( 113 enumerate_context.instance()); 114 udev_list_entry* devices = 115 libudev_context->instance()->udev_enumerate_get_list_entry()( 116 enumerate_context.instance()); 117 if (!devices) { 118 return false; 119 } 120 udev_list_entry* dev_list_entry = NULL; 121 const char* property_value = NULL; 122 // Macro that expands to a for-loop over the devices. 123 for (dev_list_entry = devices; dev_list_entry != NULL; 124 dev_list_entry = libudev_context->instance()-> 125 udev_list_entry_get_next()(dev_list_entry)) { 126 const char* path = libudev_context->instance()->udev_list_entry_get_name()( 127 dev_list_entry); 128 if (!path) continue; 129 udev_device* dev = 130 libudev_context->instance()->udev_device_new_from_syspath()( 131 udev_context.instance(), path); 132 if (!dev) continue; 133 const char* device_node = 134 libudev_context->instance()->udev_device_get_devnode()(dev); 135 if (!device_node || device.id.compare(device_node) != 0) { 136 continue; 137 } 138 dev = libudev_context->instance()-> 139 udev_device_get_parent_with_subsystem_devtype()( 140 dev, "usb", "usb_device"); 141 if (!dev) continue; 142 property_value = libudev_context->instance()-> 143 udev_device_get_sysattr_value()( 144 dev, property_name); 145 break; 146 } 147 if (!property_value) { 148 return false; 149 } 150 property->assign(property_value); 151 return true; 152 } 153 154 bool GetUsbId(const Device& device, std::string* usb_id) { 155 std::string id_vendor; 156 std::string id_product; 157 if (!GetUsbProperty(device, "idVendor", &id_vendor)) { 158 return false; 159 } 160 if (!GetUsbProperty(device, "idProduct", &id_product)) { 161 return false; 162 } 163 usb_id->clear(); 164 usb_id->append(id_vendor); 165 usb_id->append(":"); 166 usb_id->append(id_product); 167 return true; 168 } 169 170 bool GetUsbVersion(const Device& device, std::string* usb_version) { 171 return GetUsbProperty(device, "version", usb_version); 172 } 173 174 } // namespace cricket 175