1 /* 2 * Copyright (C) 2009 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ANDROID_USB_API_ADB_WINUSB_ENDPOINT_OBJECT_H__ 18 #define ANDROID_USB_API_ADB_WINUSB_ENDPOINT_OBJECT_H__ 19 /** \file 20 This file consists of declaration of class AdbWinUsbEndpointObject that 21 encapsulates a handle opened to a WinUsb endpoint on our device. 22 */ 23 24 #include "..\api\adb_endpoint_object.h" 25 #include "adb_winusb_interface.h" 26 27 /** Class AdbWinUsbEndpointObject encapsulates a handle opened to an endpoint on 28 our device. 29 */ 30 class AdbWinUsbEndpointObject : public AdbEndpointObject { 31 public: 32 /** \brief Constructs the object 33 34 @param[in] interface Parent WinUsb interface for this object. 35 @param[in] endpoint_id Endpoint ID (endpoint address) on the device. 36 @param[in] endpoint_index Zero-based endpoint index in the interface's 37 array of endpoints. 38 */ 39 AdbWinUsbEndpointObject(AdbWinUsbInterfaceObject* parent_interf, 40 UCHAR endpoint_id, 41 UCHAR endpoint_index); 42 43 protected: 44 /** \brief Destructs the object. 45 46 We hide destructor in order to prevent ourseves from accidentaly allocating 47 instances on the stack. If such attemp occur, compiler will error. 48 */ 49 virtual ~AdbWinUsbEndpointObject(); 50 51 // 52 // Virtual overrides 53 // 54 55 public: 56 /** \brief Releases the object. 57 58 If refcount drops to zero as the result of this release, the object is 59 destroyed in this method. As a general rule, objects must not be touched 60 after this method returns even if returned value is not zero. We override 61 this method in order to make sure that objects of this class are deleted 62 in contect of the DLL they were created in. The problem is that since 63 objects of this class were created in context of AdbWinUsbApi module, they 64 are allocated from the heap assigned to that module. Now, if these objects 65 are deleted outside of AdbWinUsbApi module, this will lead to the heap 66 corruption in the module that deleted these objects. Since all objects of 67 this class are deleted in the Release method only, by overriding it we make 68 sure that we free memory in the context of the module where it was 69 allocated. 70 @return Value of the reference counter after object is released in this 71 method. 72 */ 73 virtual LONG Release(); 74 75 /** \brief This method is called when handle to this object gets closed. 76 77 In this call object is deleted from the AdbObjectHandleMap. We override 78 this method in order to abort pending IOs and to prevent new IOs from 79 starting up. 80 @return true on success or false if object is already closed. If 81 false is returned GetLastError() provides extended error 82 information. 83 */ 84 virtual bool CloseHandle(); 85 86 // 87 // Abstract overrides 88 // 89 90 protected: 91 /** \brief Common code for async read / write 92 93 @param[in] is_read Read or write selector. 94 @param[in,out] buffer Pointer to the buffer for read / write. 95 @param[in] bytes_to_transfer Number of bytes to be read / written. 96 @param[out] bytes_transferred Number of bytes read / written. Can be NULL. 97 @param[in] event_handle Event handle that should be signaled when async I/O 98 completes. Can be NULL. If it's not NULL this handle will be used to 99 initialize OVERLAPPED structure for this I/O. 100 @param[in] time_out A timeout (in milliseconds) required for this I/O to 101 complete. Zero value in this parameter means that there is no 102 timeout set for this I/O. 103 @return A handle to IO completion object or NULL on failure. If NULL is 104 returned GetLastError() provides extended error information. 105 */ 106 virtual ADBAPIHANDLE CommonAsyncReadWrite(bool is_read, 107 void* buffer, 108 ULONG bytes_to_transfer, 109 ULONG* bytes_transferred, 110 HANDLE event_handle, 111 ULONG time_out); 112 113 /** \brief Common code for sync read / write 114 115 @param[in] is_read Read or write selector. 116 @param[in,out] buffer Pointer to the buffer for read / write. 117 @param[in] bytes_to_transfer Number of bytes to be read / written. 118 @param[out] bytes_transferred Number of bytes read / written. Can be NULL. 119 @param[in] time_out A timeout (in milliseconds) required for this I/O to 120 complete. Zero value in this parameter means that there is no 121 timeout set for this I/O. 122 @return true on success, false on failure. If false is returned 123 GetLastError() provides extended error information. 124 */ 125 virtual bool CommonSyncReadWrite(bool is_read, 126 void* buffer, 127 ULONG bytes_to_transfer, 128 ULONG* bytes_transferred, 129 ULONG time_out); 130 131 // 132 // Operations 133 // 134 135 protected: 136 /** \brief Sets read / write operation timeout. 137 138 @param[in] timeout Timeout value in milliseconds to use for current read 139 or write operation. Zero value passed in this parameters indicate 140 not timeout at all. Note that timeout that is set with this method is 141 global per endpoint (pipe). I.e. once set, it will be used against 142 all read / write operations performed on this endpoint, untill 143 another call to this method modifies it. This is a WinUsb design 144 flaw. Microsoft is aware of this and (hopefuly) future versions of 145 WinUsb framework will accept a timeout parameter in WinUsb_Read/Write 146 routines. For the purposes of ADB this flaw doesn't apperar to be an 147 issue, since we use single-threaded synchronous read / writes, so 148 there is no conflict in setting per-endpoint timeouts. 149 @return true on success, false on failure. If false is returned 150 GetLastError() provides extended error information. 151 */ 152 virtual bool SetTimeout(ULONG timeout); 153 154 public: 155 /// Gets parent WinUsb interface 156 AdbWinUsbInterfaceObject* parent_winusb_interface() const { 157 return reinterpret_cast<AdbWinUsbInterfaceObject*>(parent_interface()); 158 } 159 160 /// Gets parent interface WinUsb handle 161 WINUSB_INTERFACE_HANDLE winusb_handle() const { 162 return parent_winusb_interface()->winusb_handle(); 163 } 164 165 protected: 166 /// Helper class whose destructor decrements pending_io_count_. 167 class DecrementPendingIO { 168 public: 169 DecrementPendingIO(AdbWinUsbEndpointObject* endpoint) 170 : endpoint_(endpoint) {} 171 ~DecrementPendingIO() { 172 endpoint_->lock_.Lock(); 173 ATLASSERT(endpoint_->pending_io_count_ > 0); 174 --(endpoint_->pending_io_count_); 175 endpoint_->lock_.Unlock(); 176 } 177 private: 178 AdbWinUsbEndpointObject* endpoint_; 179 }; 180 181 protected: 182 /// Protects is_closing_ and pending_io_count_. 183 CComAutoCriticalSection lock_; 184 185 /// Once set, prevents new IOs from starting up. 186 bool is_closing_; 187 188 /// Count of pending IOs potentially blocked in WinUsb APIs. 189 ULONG pending_io_count_; 190 }; 191 192 #endif // ANDROID_USB_API_ADB_WINUSB_ENDPOINT_OBJECT_H__ 193
