Experimental USB API implementation.

chrome/browser/usb/usb_device.cc

+// Copyright (c) 2012 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 "chrome/browser/usb/usb_device.h"
+
+#include "base/stl_util.h"
+#include "base/synchronization/lock.h"
+#include "chrome/browser/usb/usb_service.h"
+#include "third_party/libusb/libusb/libusb.h"
+
+namespace {
+
+static uint8 ConvertTransferDirection(
+    const UsbDevice::TransferDirection direction) {
+  switch (direction) {
+    case UsbDevice::IN:
+      return LIBUSB_ENDPOINT_IN;
+    case UsbDevice::OUT:
+      return LIBUSB_ENDPOINT_OUT;
+  }
+  NOTREACHED();
+}
+
+static uint8 CreateRequestType(const UsbDevice::TransferDirection direction,
+    const UsbDevice::TransferRequestType request_type,
+    const UsbDevice::TransferRecipient recipient) {
+  uint8 result = ConvertTransferDirection(direction);
+
+  switch (request_type) {
+    case UsbDevice::STANDARD:
+      result |= LIBUSB_REQUEST_TYPE_STANDARD;
+      break;
+    case UsbDevice::CLASS:
+      result |= LIBUSB_REQUEST_TYPE_CLASS;
+      break;
+    case UsbDevice::VENDOR:
+      result |= LIBUSB_REQUEST_TYPE_VENDOR;
+      break;
+    case UsbDevice::RESERVED:
+      result |= LIBUSB_REQUEST_TYPE_RESERVED;
+      break;
+  }
+
+  switch (recipient) {
+    case UsbDevice::DEVICE:
+      result |= LIBUSB_RECIPIENT_DEVICE;
+      break;
+    case UsbDevice::INTERFACE:
+      result |= LIBUSB_RECIPIENT_INTERFACE;
+      break;
+    case UsbDevice::ENDPOINT:
+      result |= LIBUSB_RECIPIENT_ENDPOINT;
+      break;
+    case UsbDevice::OTHER:
+      result |= LIBUSB_RECIPIENT_OTHER;
+      break;
+  }
+
+  return result;
+}
+
+static void HandleTransferCompletion(struct libusb_transfer *transfer) {
+  UsbDevice *const device = reinterpret_cast<UsbDevice *>(transfer->user_data);
+  device->TransferComplete(transfer);
+}
+
+}  // namespace
+
+UsbDevice::UsbDevice(UsbService *service, PlatformUsbDeviceHandle handle)
+    : service_(service), handle_(handle) {
+  DCHECK(handle) << "Cannot create device with NULL handle.";
+}
+
+UsbDevice::~UsbDevice() {}
+
+void UsbDevice::Close() {
+  CheckDevice();
+  service_->CloseDevice(this);
+  handle_ = NULL;
+}
+
+void UsbDevice::TransferComplete(PlatformUsbTransferHandle handle) {
+  base::AutoLock lock(lock_);
+
+  DCHECK(ContainsKey(transfers_, handle)) << "Missing transfer completed";
+  Transfer *const transfer = &transfers_[handle];
+  if (transfer->buffer.get()) {
+    transfer->callback.Run(true);
+  }
+
+  transfers_.erase(handle);
+  libusb_free_transfer(handle);
+}
+
+void UsbDevice::ControlTransfer(const TransferDirection direction,
+    const TransferRequestType request_type, const TransferRecipient recipient,
+    const uint8 request, const uint16 value, const uint16 index,
+    net::IOBuffer *buffer, const size_t length, const unsigned int timeout,
+    const net::CompletionCallback &callback) {
+  CheckDevice();
+
+  struct libusb_transfer *const transfer = libusb_alloc_transfer(0);
+  const uint8 converted_type = CreateRequestType(direction, request_type,
+                                                 recipient);
+  libusb_fill_control_setup(reinterpret_cast<unsigned char *>(buffer->data()),
+                            converted_type, request, value, index, length);
+  libusb_fill_control_transfer(transfer, handle_,
+      reinterpret_cast<unsigned char *>(buffer->data()),
+      &HandleTransferCompletion, this, timeout);
+  AddTransfer(transfer, buffer, callback);
+  libusb_submit_transfer(transfer);
+}
+
+void UsbDevice::BulkTransfer(const TransferDirection direction,
+    const uint8 endpoint, net::IOBuffer *buffer, const size_t length,
+    const unsigned int timeout, const net::CompletionCallback &callback) {
+  CheckDevice();
+
+  struct libusb_transfer *const transfer = libusb_alloc_transfer(0);
+  const uint8 new_endpoint = ConvertTransferDirection(direction) | endpoint;
+  libusb_fill_bulk_transfer(transfer, handle_, new_endpoint,
+      reinterpret_cast<unsigned char *>(buffer->data()), length,
+      &HandleTransferCompletion, this, timeout);
+  AddTransfer(transfer, buffer, callback);
+  libusb_submit_transfer(transfer);
+}
+
+void UsbDevice::InterruptTransfer(const TransferDirection direction,
+    const uint8 endpoint, net::IOBuffer *buffer, const size_t length,
+    const unsigned int timeout, const net::CompletionCallback &callback) {
+  CheckDevice();
+
+  struct libusb_transfer *const transfer = libusb_alloc_transfer(0);
+  const uint8 new_endpoint = ConvertTransferDirection(direction) | endpoint;
+  libusb_fill_interrupt_transfer(transfer, handle_, new_endpoint,
+      reinterpret_cast<unsigned char *>(buffer->data()), length,
+      &HandleTransferCompletion, this, timeout);
+  AddTransfer(transfer, buffer, callback);
+  libusb_submit_transfer(transfer);
+}
+
+void UsbDevice::CheckDevice() {
+  DCHECK(handle_) << "Device is already closed.";
+}
+
+void UsbDevice::AddTransfer(PlatformUsbTransferHandle handle,
+                            net::IOBuffer *buffer,
+                            const net::CompletionCallback &callback) {
+  Transfer transfer;
+  transfer.buffer = buffer;
+  transfer.callback = callback;
+
+  {
+    base::AutoLock lock(lock_);
+    transfers_[handle] = transfer;
+  }
+}