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/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 {
+
+AsyncTransfer::AsyncTransfer(HANDLE file,
+                             scoped_refptr<net::IOBuffer> buffer,
+                             const HidIOCallback& callback,
+                             bool is_read)
+    : file_(file),
+      buffer_(buffer),
+      callback_(callback),
+      actual_size_(0),
+      is_read_(is_read) {
+  memset(&overlapped_, 0, sizeof(OVERLAPPED));
+  event_.Set(CreateEvent(NULL, FALSE, FALSE, NULL));
+  overlapped_.hEvent = event_.Get();
+}
+
+AsyncTransfer::~AsyncTransfer() {
+}
+
+void AsyncTransfer::StartWatching(BOOL result_from_winapi) {
+  if (!result_from_winapi) {
+    if (GetLastError() == ERROR_IO_PENDING) {
+      if (watcher_.StartWatching(event_.Get(), this)) {
+        AddRef();
+      } else {
+        callback_.Run(false, NULL, 0);
+      }
+    } else {
+      PLOG(ERROR) << "HidConnectionWin::Read";
+      callback_.Run(false, NULL, 0);
+    }
+  } else {
+    AddRef();
+    OnObjectSignaled(overlapped_.hEvent);
+  }
+}
+
+OVERLAPPED* AsyncTransfer::GetOverlappedPtr() {
+  return &overlapped_;
+}
+
+DWORD* AsyncTransfer::GetActualSizePtr() {
+  return &actual_size_;
+}
+
+void AsyncTransfer::OnObjectSignaled(HANDLE object) {
+  DCHECK_EQ(object, event_.Get());
+  BOOL result = GetOverlappedResult(file_,&overlapped_, &actual_size_, FALSE);
+
+  // For input transfers, if the first byte is zero, we need to remove it.
+  if (is_read_ && buffer_->data()[0] == 0) {
+    actual_size_--;
+    memmove(buffer_->data(), buffer_->data() + 1, actual_size_);
+  }
+  callback_.Run(result != 0, buffer_, (size_t)actual_size_);
+  Release();
+}
+
+HidConnectionWin::HidConnectionWin(HidDeviceInfo device_info)
+    : HidConnection(device_info),
+      available_(false) {
+  file_.Set(CreateFileA(device_info.device_id.c_str(),
+                        GENERIC_WRITE | GENERIC_READ,
+                        FILE_SHARE_READ,
+                        NULL,
+                        OPEN_EXISTING,
+                        FILE_FLAG_OVERLAPPED,
+                        NULL));
+  available_ = file_.Get() != INVALID_HANDLE_VALUE;
+}
+
+HidConnectionWin::~HidConnectionWin() {}
+
+void HidConnectionWin::Read(const HidIOCallback& callback) {
+  size_t report_size = device_info_.input_report_size;
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(report_size));
+  scoped_refptr<AsyncTransfer> aync_transfer(
+      new AsyncTransfer(file_, buffer, callback, true));
+
+  aync_transfer->StartWatching(ReadFile(file_.Get(),
+                                        buffer->data(),
+                                        report_size,
+                                        aync_transfer->GetActualSizePtr(),
+                                        aync_transfer->GetOverlappedPtr()));
+}
+
+void HidConnectionWin::Write(scoped_refptr<net::IOBuffer> buffer,
+                             size_t size,
+                             const HidIOCallback& callback) {
+  size_t report_size = device_info_.output_report_size;
+  if (size < report_size) {
+    scoped_refptr<net::IOBuffer> expanded_buffer(
+        new net::IOBuffer(report_size));
+    memset(expanded_buffer->data(), 0, report_size);
+    memcpy(expanded_buffer->data(), buffer->data(), size);
+    size = report_size;
+    buffer = expanded_buffer;
+  }
+
+  scoped_refptr<AsyncTransfer> aync_transfer(
+      new AsyncTransfer(file_, NULL, callback, false));
+
+  aync_transfer->StartWatching(WriteFile(file_,
+                                         buffer->data(),
+                                         size,
+                                         aync_transfer->GetActualSizePtr(),
+                                         aync_transfer->GetOverlappedPtr()));
+}
+
+void HidConnectionWin::GetFeatureReport(const HidIOCallback& callback) {
+  size_t report_size = device_info_.feature_report_size;
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(report_size));
+  scoped_refptr<AsyncTransfer> aync_transfer(
+      new AsyncTransfer(file_, buffer, callback, true));
+
+  aync_transfer->
+      StartWatching(DeviceIoControl(file_,
+                                    IOCTL_HID_GET_FEATURE,
+                                    NULL, 0,
+                                    buffer->data(), report_size,
+                                    aync_transfer->GetActualSizePtr(),
+                                    aync_transfer->GetOverlappedPtr()));
+}
+
+void HidConnectionWin::SendFeatureReport(scoped_refptr<net::IOBuffer> buffer,
+                                         size_t size,
+                                         const HidIOCallback& callback) {
+  size_t report_size = device_info_.feature_report_size;
+  if (size < report_size) {
+    scoped_refptr<net::IOBuffer> expanded_buffer(
+        new net::IOBuffer(report_size));
+    memset(expanded_buffer->data(), 0, report_size);
+    memcpy(expanded_buffer->data(), buffer->data(), size);
+    size = report_size;
+    buffer = expanded_buffer;
+  }
+
+  scoped_refptr<AsyncTransfer> aync_transfer(
+      new AsyncTransfer(file_, NULL, callback, false));
+
+  aync_transfer->
+      StartWatching(DeviceIoControl(file_,
+                                    IOCTL_HID_SET_FEATURE,
+                                    buffer->data(), report_size,
+                                    NULL, 0,
+                                    aync_transfer->GetActualSizePtr(),
+                                    aync_transfer->GetOverlappedPtr()));
+}
+
+}  // namespace device