/* | |
* Copyright (C) 2009 The Android Open Source Project | |
* | |
* Licensed under the Apache License, Version 2.0 (the "License"); | |
* you may not use this file except in compliance with the License. | |
* You may obtain a copy of the License at | |
* | |
* http://www.apache.org/licenses/LICENSE-2.0 | |
* | |
* Unless required by applicable law or agreed to in writing, software | |
* distributed under the License is distributed on an "AS IS" BASIS, | |
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
* See the License for the specific language governing permissions and | |
* limitations under the License. | |
*/ | |
#ifndef ANDROID_USB_API_ADB_WINUSB_ENDPOINT_OBJECT_H__ | |
#define ANDROID_USB_API_ADB_WINUSB_ENDPOINT_OBJECT_H__ | |
/** \file | |
This file consists of declaration of class AdbWinUsbEndpointObject that | |
encapsulates a handle opened to a WinUsb endpoint on our device. | |
*/ | |
#include "..\api\adb_endpoint_object.h" | |
#include "adb_winusb_interface.h" | |
/** Class AdbWinUsbEndpointObject encapsulates a handle opened to an endpoint on | |
our device. | |
*/ | |
class AdbWinUsbEndpointObject : public AdbEndpointObject { | |
public: | |
/** \brief Constructs the object | |
@param[in] interface Parent WinUsb interface for this object. | |
@param[in] endpoint_id Endpoint ID (endpoint address) on the device. | |
@param[in] endpoint_index Zero-based endpoint index in the interface's | |
array of endpoints. | |
*/ | |
AdbWinUsbEndpointObject(AdbWinUsbInterfaceObject* parent_interf, | |
UCHAR endpoint_id, | |
UCHAR endpoint_index); | |
protected: | |
/** \brief Destructs the object. | |
We hide destructor in order to prevent ourseves from accidentaly allocating | |
instances on the stack. If such attemp occur, compiler will error. | |
*/ | |
virtual ~AdbWinUsbEndpointObject(); | |
// | |
// Virtual overrides | |
// | |
public: | |
/** \brief Releases the object. | |
If refcount drops to zero as the result of this release, the object is | |
destroyed in this method. As a general rule, objects must not be touched | |
after this method returns even if returned value is not zero. We override | |
this method in order to make sure that objects of this class are deleted | |
in contect of the DLL they were created in. The problem is that since | |
objects of this class were created in context of AdbWinUsbApi module, they | |
are allocated from the heap assigned to that module. Now, if these objects | |
are deleted outside of AdbWinUsbApi module, this will lead to the heap | |
corruption in the module that deleted these objects. Since all objects of | |
this class are deleted in the Release method only, by overriding it we make | |
sure that we free memory in the context of the module where it was | |
allocated. | |
@return Value of the reference counter after object is released in this | |
method. | |
*/ | |
virtual LONG Release(); | |
/** \brief This method is called when handle to this object gets closed. | |
In this call object is deleted from the AdbObjectHandleMap. We override | |
this method in order to abort pending IOs and to prevent new IOs from | |
starting up. | |
@return true on success or false if object is already closed. If | |
false is returned GetLastError() provides extended error | |
information. | |
*/ | |
virtual bool CloseHandle(); | |
// | |
// Abstract overrides | |
// | |
protected: | |
/** \brief Common code for async read / write | |
@param[in] is_read Read or write selector. | |
@param[in,out] buffer Pointer to the buffer for read / write. | |
@param[in] bytes_to_transfer Number of bytes to be read / written. | |
@param[out] bytes_transferred Number of bytes read / written. Can be NULL. | |
@param[in] event_handle Event handle that should be signaled when async I/O | |
completes. Can be NULL. If it's not NULL this handle will be used to | |
initialize OVERLAPPED structure for this I/O. | |
@param[in] time_out A timeout (in milliseconds) required for this I/O to | |
complete. Zero value in this parameter means that there is no | |
timeout set for this I/O. | |
@return A handle to IO completion object or NULL on failure. If NULL is | |
returned GetLastError() provides extended error information. | |
*/ | |
virtual ADBAPIHANDLE CommonAsyncReadWrite(bool is_read, | |
void* buffer, | |
ULONG bytes_to_transfer, | |
ULONG* bytes_transferred, | |
HANDLE event_handle, | |
ULONG time_out); | |
/** \brief Common code for sync read / write | |
@param[in] is_read Read or write selector. | |
@param[in,out] buffer Pointer to the buffer for read / write. | |
@param[in] bytes_to_transfer Number of bytes to be read / written. | |
@param[out] bytes_transferred Number of bytes read / written. Can be NULL. | |
@param[in] time_out A timeout (in milliseconds) required for this I/O to | |
complete. Zero value in this parameter means that there is no | |
timeout set for this I/O. | |
@return true on success, false on failure. If false is returned | |
GetLastError() provides extended error information. | |
*/ | |
virtual bool CommonSyncReadWrite(bool is_read, | |
void* buffer, | |
ULONG bytes_to_transfer, | |
ULONG* bytes_transferred, | |
ULONG time_out); | |
// | |
// Operations | |
// | |
protected: | |
/** \brief Sets read / write operation timeout. | |
@param[in] timeout Timeout value in milliseconds to use for current read | |
or write operation. Zero value passed in this parameters indicate | |
not timeout at all. Note that timeout that is set with this method is | |
global per endpoint (pipe). I.e. once set, it will be used against | |
all read / write operations performed on this endpoint, untill | |
another call to this method modifies it. This is a WinUsb design | |
flaw. Microsoft is aware of this and (hopefuly) future versions of | |
WinUsb framework will accept a timeout parameter in WinUsb_Read/Write | |
routines. For the purposes of ADB this flaw doesn't apperar to be an | |
issue, since we use single-threaded synchronous read / writes, so | |
there is no conflict in setting per-endpoint timeouts. | |
@return true on success, false on failure. If false is returned | |
GetLastError() provides extended error information. | |
*/ | |
virtual bool SetTimeout(ULONG timeout); | |
public: | |
/// Gets parent WinUsb interface | |
AdbWinUsbInterfaceObject* parent_winusb_interface() const { | |
return reinterpret_cast<AdbWinUsbInterfaceObject*>(parent_interface()); | |
} | |
/// Gets parent interface WinUsb handle | |
WINUSB_INTERFACE_HANDLE winusb_handle() const { | |
return parent_winusb_interface()->winusb_handle(); | |
} | |
protected: | |
/// Helper class whose destructor decrements pending_io_count_. | |
class DecrementPendingIO { | |
public: | |
DecrementPendingIO(AdbWinUsbEndpointObject* endpoint) | |
: endpoint_(endpoint) {} | |
~DecrementPendingIO() { | |
endpoint_->lock_.Lock(); | |
ATLASSERT(endpoint_->pending_io_count_ > 0); | |
--(endpoint_->pending_io_count_); | |
endpoint_->lock_.Unlock(); | |
} | |
private: | |
AdbWinUsbEndpointObject* endpoint_; | |
}; | |
protected: | |
/// Protects is_closing_ and pending_io_count_. | |
CComAutoCriticalSection lock_; | |
/// Once set, prevents new IOs from starting up. | |
bool is_closing_; | |
/// Count of pending IOs potentially blocked in WinUsb APIs. | |
ULONG pending_io_count_; | |
}; | |
#endif // ANDROID_USB_API_ADB_WINUSB_ENDPOINT_OBJECT_H__ |