HID backend

device/hid/hid_connection_win.cc

+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "device/hid/hid_connection_win.h"
+
+#include <cstring>
+
+#include "base/message_loop/message_loop.h"
+#include "base/stl_util.h"
+#include "base/threading/thread_restrictions.h"
+#include "device/hid/hid_service.h"
+#include "device/hid/hid_service_win.h"
+#include "net/base/io_buffer.h"
+
+#if defined(OS_WIN)
+
+#define INITGUID
+
+#include <windows.h>
+#include <hidclass.h>
+
+extern "C" {
+
+#include <hidsdi.h>
+
+}
+
+#include <setupapi.h>
+#include <winioctl.h>
+#include "base/win/scoped_handle.h"
+
+#endif  // defined(OS_WIN)
+
+namespace device {
+
+HidConnectionWin::PendingTransfer::PendingTransfer(
+    scoped_refptr<HidConnectionWin> conn,
+    scoped_refptr<net::IOBuffer> target,
+    scoped_refptr<net::IOBuffer> receiving,
+    bool is_input,
+    IOCallback callback)
+    : conn_(conn),
+      is_input_(is_input),
+      target_(target),
+      receiving_(receiving),
+      callback_(callback),
+      event_(CreateEvent(NULL, FALSE, FALSE, NULL)) {
+  memset(&overlapped_, 0, sizeof(OVERLAPPED));
+  overlapped_.hEvent = event_.Get();
+}
+HidConnectionWin::PendingTransfer::~PendingTransfer() {
+  base::MessageLoop::current()->RemoveDestructionObserver(this);
+}
+
+void HidConnectionWin::PendingTransfer::TakeResultFromWindowsAPI(BOOL result) {
+  if (result || GetLastError() != ERROR_IO_PENDING) {
+    conn_->OnTransferFinished(this);
+  } else {
+    base::MessageLoop::current()->AddDestructionObserver(this);
+    AddRef();
+    watcher_.StartWatching(event_.Get(), this);
+  }
+}
+
+void HidConnectionWin::PendingTransfer::OnObjectSignaled(HANDLE event_handle) {
+  conn_->OnTransferFinished(this);
+  Release();
+}
+
+void HidConnectionWin::PendingTransfer::WillDestroyCurrentMessageLoop() {
+  watcher_.StopWatching();
+  conn_->OnTransferCanceled(this);
+}
+
+void HidConnectionWin::OnTransferFinished(
+    scoped_refptr<PendingTransfer> transfer) {
+  DWORD bytes_transfered;

[miket_OOO, 2014/02/03 18:42:19]

I think the preferred spelling has a double-r, not a huge deal

+  transfers_.erase(transfer);
+  if (GetOverlappedResult(file_,
+                          transfer->GetOverlapped(),
+                          &bytes_transfered,
+                          FALSE)) {
+    if (transfer->is_input_ && !device_info_.has_report_id) {
+      // Move one byte forward.
+      --bytes_transfered;
+      memcpy(transfer->target_->data(),
+             transfer->receiving_->data() + 1,
+             bytes_transfered);
+    }
+    transfer->callback_.Run(true, bytes_transfered);
+  } else {
+    transfer->callback_.Run(false, 0);
+  }
+}
+
+void HidConnectionWin::OnTransferCanceled(
+    scoped_refptr<PendingTransfer> transfer) {
+  transfers_.erase(transfer);
+  transfer->callback_.Run(false, 0);
+}
+
+HidConnectionWin::HidConnectionWin(HidDeviceInfo device_info)
+    : HidConnection(device_info),
+      available_(false) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  file_.Set(CreateFileA(device_info.device_id.c_str(),
+                        GENERIC_WRITE | GENERIC_READ,
+                        FILE_SHARE_READ | FILE_SHARE_WRITE,
+                        NULL,
+                        OPEN_EXISTING,
+                        FILE_FLAG_OVERLAPPED,
+                        NULL));
+  available_ = file_.IsValid();
+}
+
+HidConnectionWin::~HidConnectionWin() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  CancelIo(file_.Get());
+}
+
+void HidConnectionWin::Read(scoped_refptr<net::IOBuffer> buffer,
+                            size_t size,
+                            const HidConnection::IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  size_t report_size = device_info_.input_report_size;
+  if (report_size == 0) {
+    // The device does not supoort input reports.
+    callback.Run(false, 0);
+    return;
+  }
+
+  if (size + !device_info_.has_report_id < report_size) {

[miket_OOO, 2014/02/03 18:42:19]

that is weird logic (boolean cast to int)

+    // Buffer too short.
+    callback.Run(false, 0);
+    return;
+  }
+
+  scoped_refptr<net::IOBuffer> expanded_buffer;
+  if (!device_info_.has_report_id) {
+    ++size;
+    expanded_buffer = new net::IOBuffer(size);
+  }
+
+  scoped_refptr<PendingTransfer> transfer(
+      new PendingTransfer(this, buffer, expanded_buffer, true, callback));
+  transfers_.insert(transfer);
+  transfer->TakeResultFromWindowsAPI(ReadFile(file_.Get(),
+                                              device_info_.has_report_id ?
+                                                  buffer->data() :
+                                                  expanded_buffer->data(),
+                                              size,
+                                              NULL,
+                                              transfer->GetOverlapped()));
+}
+
+void HidConnectionWin::Write(scoped_refptr<net::IOBuffer> buffer,
+                             size_t size,
+                             const HidConnection::IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  size_t report_size = device_info_.output_report_size;
+  if (report_size == 0) {
+    // The device does not supoort output reports.
+    callback.Run(false, 0);
+    return;
+  }
+
+  if (size + !device_info_.has_report_id > report_size) {
+    // Size of report too long.
+    callback.Run(false, 0);
+    return;
+  }
+
+  scoped_refptr<net::IOBuffer> expanded_buffer;
+  if (!device_info_.has_report_id) {
+    expanded_buffer = new net::IOBuffer(device_info_.output_report_size);
+    memset(expanded_buffer->data(), 0, device_info_.output_report_size);
+    memcpy(expanded_buffer->data() + 1,
+           buffer->data(),
+           size);
+    size++;
+  }
+
+  scoped_refptr<PendingTransfer> transfer(
+      new PendingTransfer(this, buffer, expanded_buffer, false, callback));
+  transfers_.insert(transfer);
+  transfer->TakeResultFromWindowsAPI(WriteFile(file_.Get(),
+                                               device_info_.has_report_id ?
+                                                   buffer->data() :
+                                                   expanded_buffer->data(),
+                                               device_info_.output_report_size,
+                                               NULL,
+                                               transfer->GetOverlapped()));
+}
+
+void HidConnectionWin::GetFeatureReport(scoped_refptr<net::IOBuffer> buffer,
+                                        size_t size,
+                                        const IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  size_t report_size = device_info_.feature_report_size;
+  if (report_size == 0) {
+    // The device does not supoort input reports.
+    callback.Run(false, 0);
+    return;
+  }
+
+  if (size + !device_info_.has_report_id < report_size) {
+    // Buffer too short.
+    callback.Run(false, 0);
+    return;
+  }
+
+  scoped_refptr<net::IOBuffer> expanded_buffer;
+  if (!device_info_.has_report_id) {
+    ++size;
+    expanded_buffer = new net::IOBuffer(size);
+  }
+
+  scoped_refptr<PendingTransfer> transfer(
+      new PendingTransfer(this, buffer, expanded_buffer, true, callback));
+  transfers_.insert(transfer);
+  transfer->TakeResultFromWindowsAPI(
+      DeviceIoControl(file_.Get(),
+                      IOCTL_HID_GET_FEATURE,
+                      NULL,
+                      0,
+                      device_info_.has_report_id ?
+                          buffer->data() :
+                          expanded_buffer->data(),
+                      size,
+                      NULL,
+                      transfer->GetOverlapped()));
+}
+
+void HidConnectionWin::SendFeatureReport(scoped_refptr<net::IOBuffer> buffer,
+                                         size_t size,
+                                         const IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  size_t report_size = device_info_.feature_report_size;
+  if (report_size == 0) {
+    // The device does not supoort output reports.
+    callback.Run(false, 0);
+    return;
+  }
+
+  if (size + !device_info_.has_report_id > report_size) {
+    // Size of report too long.
+    callback.Run(false, 0);
+    return;
+  }
+
+  scoped_refptr<net::IOBuffer> expanded_buffer;
+  if (!device_info_.has_report_id) {
+    expanded_buffer = new net::IOBuffer(device_info_.feature_report_size);
+    memset(expanded_buffer->data(), 0, device_info_.feature_report_size);
+    memcpy(expanded_buffer->data() + 1,
+           buffer->data(),
+           size);
+    size++;
+  }
+
+  scoped_refptr<PendingTransfer> transfer(
+      new PendingTransfer(this, buffer, expanded_buffer, false, callback));
+  transfer->TakeResultFromWindowsAPI(
+      DeviceIoControl(file_.Get(),
+                      IOCTL_HID_SET_FEATURE,
+                      device_info_.has_report_id ?
+                          buffer->data() :
+                          expanded_buffer->data(),
+                      device_info_.output_report_size,
+                      NULL,
+                      0,
+                      NULL,
+                      transfer->GetOverlapped()));
+}
+
+}  // namespace device