HID backend

device/hid/hid_connection_mac.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_mac.h"
+
+#include "base/bind.h"
+#include "base/callback.h"
+#include "base/mac/foundation_util.h"
+#include "base/threading/thread_restrictions.h"
+#include "base/tuple.h"
+#include "device/hid/hid_service.h"
+#include "device/hid/hid_service_mac.h"
+#include "net/base/io_buffer.h"
+
+#include <CoreFoundation/CoreFoundation.h>
+#include <IOKit/hid/IOHIDManager.h>
+
+namespace device {
+
+HidConnectionMac::HidConnectionMac(HidServiceMac* service,
+                                   HidDeviceInfo device_info,
+                                   IOHIDDeviceRef device)
+    : HidConnection(device_info),
+      service_(service),
+      device_(device),
+      disconnected_(false) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  message_loop_ = base::MessageLoopProxy::current();
+
+  CFRetain(device);
+  inbound_buffer_.reset((uint8_t*) malloc(device_info.input_report_size + 1));
+  IOHIDDeviceRegisterInputReportCallback(
+      device_.get(),
+      inbound_buffer_.get(),
+      device_info.input_report_size + 1,
+      &HidConnectionMac::InputReportCallback,
+      this);
+  IOHIDDeviceOpen(device_, kIOHIDOptionsTypeNone);
+}
+HidConnectionMac::~HidConnectionMac() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  while (read_queue_.size()) {
+    read_queue_.front().c.Run(false, 0);
+    read_queue_.pop();
+  }
+
+  IOHIDDeviceClose(device_, kIOHIDOptionsTypeNone);
+}
+
+void HidConnectionMac::InputReportCallback(void * context,
+                                           IOReturn result,
+                                           void * sender,
+                                           IOHIDReportType type,
+                                           uint32_t reportID,
+                                           uint8_t * report,
+                                           CFIndex reportLength) {
+  HidConnectionMac* connection = reinterpret_cast<HidConnectionMac*>(context);
+  size_t length = reportLength + (reportID != 0);
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(length));
+  if (reportID) {
+    buffer->data()[0] = reportID;
+    memcpy(buffer->data() + 1, report, reportLength);
+  } else {
+    memcpy(buffer->data(), report, reportLength);
+  }
+  connection->message_loop_->PostTask(
+      FROM_HERE,
+      base::Bind(&HidConnectionMac::ProcessInputReport,
+                 connection,
+                 type,
+                 buffer,
+                 length));
+}
+
+void HidConnectionMac::ProcessReadQueue() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  while(read_queue_.size() && input_reports_.size()) {
+    PendingRead read = read_queue_.front();
+    read_queue_.pop();
+    PendingReport report = input_reports_.front();
+
+    if (read.b < report.second) {
+      read.c.Run(false, report.second);
+    } else {
+      memcpy(read.a->data(), report.first->data(), report.second);
+      input_reports_.pop();
+      read.c.Run(true, report.second);
+    }
+  }
+}
+
+void HidConnectionMac::ProcessInputReport(IOHIDReportType type,
+                                          scoped_refptr<net::IOBuffer> report,
+                                          CFIndex reportLength) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  input_reports_.push(std::make_pair(report, reportLength));
+  ProcessReadQueue();
+}
+
+void HidConnectionMac::WriteReport(IOHIDReportType type,
+                                   scoped_refptr<net::IOBuffer> buffer,
+                                   size_t size,
+                                   const IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  if (disconnected_ || !device_) {
+    callback.Run(false, 0);
+    return;
+  }
+  const unsigned char* data_to_send =
+      reinterpret_cast<const unsigned char*>(buffer->data());
+  size_t length_to_send = size;
+  if (data_to_send[0] == 0x0) {
+      /* Not using numbered Reports.
+       Don't send the report number. */
+      ++data_to_send;
+      --length_to_send;
+  }
+  IOReturn res = IOHIDDeviceSetReport(device_.get(),
+                                      type,
+                                      buffer->data()[0], /* Report ID*/
+                                      data_to_send,
+                                      length_to_send);
+  if (res != kIOReturnSuccess) {
+    callback.Run(false, 0);
+  } else {
+    callback.Run(true, size);
+  }
+}
+
+void HidConnectionMac::Read(scoped_refptr<net::IOBuffer> buffer,
+                            size_t size,
+                            const IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  if (disconnected_ || !device_) {
+    callback.Run(false, 0);
+    return;
+  }
+  read_queue_.push(MakeTuple(buffer, size, callback));
+  ProcessReadQueue();
+}
+
+void HidConnectionMac::Write(scoped_refptr<net::IOBuffer> buffer,
+                             size_t size,
+                             const IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  WriteReport(kIOHIDReportTypeOutput, buffer, size, callback);
+}
+
+void HidConnectionMac::SendFeatureReport(scoped_refptr<net::IOBuffer> buffer,
+                                         size_t size,
+                                         const IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  WriteReport(kIOHIDReportTypeFeature, buffer, size, callback);
+}
+
+void HidConnectionMac::GetFeatureReport(scoped_refptr<net::IOBuffer> buffer,
+                                        size_t size,
+                                        const IOCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  if (disconnected_ || !device_ || device_info_.feature_report_size == 0) {
+    callback.Run(false, 0);
+    return;
+  }
+
+  if (device_info_.feature_report_size != 0 &&
+      device_info_.feature_report_size != size) {
+    callback.Run(false, 0);
+    return;
+  }
+
+  CFIndex len = device_info_.feature_report_size;
+  IOReturn res = IOHIDDeviceGetReport(device_,
+                                      kIOHIDReportTypeFeature,
+                                      0,
+                                      (uint8_t*) buffer->data(),
+                                      &len);
+  if (res == kIOReturnSuccess)
+    callback.Run(true, len);
+  else
+    callback.Run(false, 0);
+}
+
+}  // namespace device