Experimental USB API

chrome/browser/extensions/api/usb/usb_device_resource.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/extensions/api/usb/usb_device_resource.h"
+
+#include <string>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/synchronization/lock.h"
+#include "chrome/browser/extensions/api/api_resource_event_notifier.h"
+#include "chrome/browser/extensions/api/api_resource.h"
+#include "chrome/browser/usb/usb_device.h"
+#include "chrome/common/extensions/api/experimental.usb.h"
+
+using extensions::api::experimental_usb::ControlTransferInfo;
+using extensions::api::experimental_usb::GenericTransferInfo;
+using std::string;
+using std::vector;
+
+static const char* kDirectionIn = "in";
+static const char* kDirectionOut = "out";
+
+static const char* kRequestTypeStandard = "standard";
+static const char* kRequestTypeClass = "class";
+static const char* kRequestTypeVendor = "vendor";
+static const char* kRequestTypeReserved = "reserved";
+
+static const char* kRecipientDevice = "device";
+static const char* kRecipientInterface = "interface";
+static const char* kRecipientEndpoint = "endpoint";
+static const char* kRecipientOther = "other";
+
+namespace {
+
+static bool ConvertDirection(const string& input,
+                             UsbDevice::TransferDirection* output) {
+  if (input == kDirectionIn) {
+    *output = UsbDevice::IN;
+    return true;
+  } else if (input == kDirectionOut) {
+    *output = UsbDevice::OUT;
+    return true;
+  }
+  return false;
+}
+
+static bool ConvertRequestType(const string& input,
+                               UsbDevice::TransferRequestType* output) {
+  if (input == kRequestTypeStandard) {
+    *output = UsbDevice::STANDARD;
+    return true;
+  } else if (input == kRequestTypeClass) {
+    *output = UsbDevice::CLASS;
+    return true;
+  } else if (input == kRequestTypeVendor) {
+    *output = UsbDevice::VENDOR;
+    return true;
+  } else if (input == kRequestTypeReserved) {
+    *output = UsbDevice::RESERVED;
+    return true;
+  }
+  return false;
+}
+
+static bool ConvertRecipient(const string& input,
+                             UsbDevice::TransferRecipient* output) {
+  if (input == kRecipientDevice) {
+    *output = UsbDevice::DEVICE;
+    return true;
+  } else if (input == kRecipientInterface) {
+    *output = UsbDevice::INTERFACE;
+    return true;
+  } else if (input == kRecipientEndpoint) {
+    *output = UsbDevice::ENDPOINT;
+    return true;
+  } else if (input == kRecipientOther) {
+    *output = UsbDevice::OTHER;
+    return true;
+  }
+  return false;
+}
+
+template<class T>
+static bool GetTransferSize(const T& input, unsigned int* output) {
+  if (input.direction == kDirectionIn) {
+    const int* length = input.length.get();
+    if (length) {
+      *output = *length;
+      return true;
+    }
+  } else if (input.direction == kDirectionOut) {
+    if (input.data.get()) {
+      *output = input.data->size();
+      return true;
+    }
+  }
+  return false;
+}
+
+template<class T>
+static scoped_refptr<net::IOBuffer> CreateBufferForTransfer(const T& input) {
+  unsigned int size = 0;
+  if (!GetTransferSize(input, &size)) {
+    return NULL;
+  }
+
+  scoped_refptr<net::IOBuffer> buffer = new net::IOBuffer(size);
+  if (!input.data.get()) {
+    return buffer;
+  }
+
+  const vector<int>& input_buffer = *input.data.get();
+  for (unsigned int i = 0; i < size; ++i) {
+    buffer->data()[i] = input_buffer[i];
+  }
+
+  return buffer;
+}
+
+}  // namespace
+
+namespace extensions {
+
+UsbDeviceResource::UsbDeviceResource(APIResourceEventNotifier* notifier,
+                                     UsbDevice* device)
+    : APIResource(APIResource::UsbDeviceResource, notifier), device_(device),
+      pending_transfers_(0) {}
+
+UsbDeviceResource::~UsbDeviceResource() {
+  if (pending_transfers_) {
+    LOG(ERROR) << "There are transfers still in flight.";
+  }
+}
+
+void UsbDeviceResource::ControlTransfer(const ControlTransferInfo& transfer) {
+  UsbDevice::TransferDirection direction;
+  UsbDevice::TransferRequestType request_type;
+  UsbDevice::TransferRecipient recipient;
+  unsigned int size;
+  scoped_refptr<net::IOBuffer> buffer = CreateBufferForTransfer(transfer);
+
+  if (!ConvertDirection(transfer.direction, &direction) ||
+      !ConvertRequestType(transfer.request_type, &request_type) ||
+      !ConvertRecipient(transfer.recipient, &recipient) ||
+      !GetTransferSize(transfer, &size) || !buffer) {
+    LOG(INFO) << "Malformed transfer parameters.";
+    return;
+  }
+
+  device_->ControlTransfer(direction, request_type, recipient, transfer.request,
+                           transfer.value, transfer.index, buffer, size, 0,
+                           base::Bind(&UsbDeviceResource::TransferComplete,
+                                      base::Unretained(this), buffer, size));
+}
+
+void UsbDeviceResource::InterruptTransfer(const GenericTransferInfo& transfer) {
+  unsigned int size;
+  UsbDevice::TransferDirection direction;
+  scoped_refptr<net::IOBuffer> buffer = CreateBufferForTransfer(transfer);
+
+  if (!ConvertDirection(transfer.direction, &direction) ||
+      !GetTransferSize(transfer, &size) || !buffer) {
+    LOG(INFO) << "Malformed transfer parameters.";
+    return;
+  }
+
+  device_->InterruptTransfer(direction, transfer.endpoint, buffer, size, 0,
+                             base::Bind(&UsbDeviceResource::TransferComplete,
+                                        base::Unretained(this), buffer, size));
+}
+
+void UsbDeviceResource::BulkTransfer(const GenericTransferInfo& transfer) {
+  unsigned int size;
+  UsbDevice::TransferDirection direction;
+  scoped_refptr<net::IOBuffer> buffer = CreateBufferForTransfer(transfer);
+
+  if (!ConvertDirection(transfer.direction, &direction) ||
+      !GetTransferSize(transfer, &size) || !buffer) {
+    LOG(INFO) << "Malformed transfer parameters.";
+    return;
+  }
+
+  device_->BulkTransfer(direction, transfer.endpoint, buffer, size, 0,
+                        base::Bind(&UsbDeviceResource::TransferComplete,
+                                   base::Unretained(this), buffer, size));
+}
+
+void UsbDeviceResource::TransferComplete(net::IOBuffer* buffer,
+                                         const size_t length,
+                                         int success) {
+  if (buffer) {
+    base::ListValue *const response_buffer = new base::ListValue();
+    for (unsigned int i = 0; i < length; ++i) {
+      const uint8_t value = buffer->data()[i] & 0xFF;
+      response_buffer->Append(base::Value::CreateIntegerValue(value));
+    }
+    event_notifier()->OnTransferComplete(success, response_buffer);
+  }
+}
+
+}  // namespace extensions