Separate usb device handle from usb device. (deprecate)

chrome/browser/usb/usb_device_handle.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 "chrome/browser/usb/usb_device_handle.h"
 
 #include <vector>
 
 #include "base/stl_util.h"
 #include "base/synchronization/lock.h"
 #include "chrome/browser/usb/usb_interface.h"
 #include "chrome/browser/usb/usb_service.h"
+#include "content/public/browser/browser_thread.h"
 #include "third_party/libusb/src/libusb/libusb.h"
 
+using content::BrowserThread;
+
+#define CHECK_DEVICE(callback, args...) \
+  do { \
+    if (handle_ == NULL) { \
+      DVLOG(1) << "Device is disconnected: "; \
+      callback.Run(args);\
+      return; \
+    } \
+  } while (0)
+
+#define CHECK_DEVICE_RETURN \
+  do { \
+    if (handle_ == NULL) { \
+      DVLOG(1) << "Device is disconnected: "; \
+      return; \
+    } \
+  } while (0)
+
 namespace {
 
 static uint8 ConvertTransferDirection(
     const UsbEndpointDirection direction) {
   switch (direction) {
     case USB_DIRECTION_INBOUND:
       return LIBUSB_ENDPOINT_IN;
     case USB_DIRECTION_OUTBOUND:
       return LIBUSB_ENDPOINT_OUT;
     default:
       NOTREACHED();
       return LIBUSB_ENDPOINT_IN;
   }
 }
 
 static uint8 CreateRequestType(const UsbEndpointDirection direction,
-    const UsbDevice::TransferRequestType request_type,
-    const UsbDevice::TransferRecipient recipient) {
+    const UsbDeviceHandle::TransferRequestType request_type,
+    const UsbDeviceHandle::TransferRecipient recipient) {
   uint8 result = ConvertTransferDirection(direction);
 
   switch (request_type) {
-    case UsbDevice::STANDARD:
+    case UsbDeviceHandle::STANDARD:
       result |= LIBUSB_REQUEST_TYPE_STANDARD;
       break;
-    case UsbDevice::CLASS:
+    case UsbDeviceHandle::CLASS:
       result |= LIBUSB_REQUEST_TYPE_CLASS;
       break;
-    case UsbDevice::VENDOR:
+    case UsbDeviceHandle::VENDOR:
       result |= LIBUSB_REQUEST_TYPE_VENDOR;
       break;
-    case UsbDevice::RESERVED:
+    case UsbDeviceHandle::RESERVED:
       result |= LIBUSB_REQUEST_TYPE_RESERVED;
       break;
   }
 
   switch (recipient) {
-    case UsbDevice::DEVICE:
+    case UsbDeviceHandle::DEVICE:
       result |= LIBUSB_RECIPIENT_DEVICE;
       break;
-    case UsbDevice::INTERFACE:
+    case UsbDeviceHandle::INTERFACE:
       result |= LIBUSB_RECIPIENT_INTERFACE;
       break;
-    case UsbDevice::ENDPOINT:
+    case UsbDeviceHandle::ENDPOINT:
       result |= LIBUSB_RECIPIENT_ENDPOINT;
       break;
-    case UsbDevice::OTHER:
+    case UsbDeviceHandle::OTHER:
       result |= LIBUSB_RECIPIENT_OTHER;
       break;
   }
 
   return result;
 }
 
 static UsbTransferStatus ConvertTransferStatus(
     const libusb_transfer_status status) {
   switch (status) {
@@ skipping 10 matching lines @@
     case LIBUSB_TRANSFER_OVERFLOW:
       return USB_TRANSFER_OVERFLOW;
     case LIBUSB_TRANSFER_CANCELLED:
       return USB_TRANSFER_CANCELLED;
     default:
       NOTREACHED();
       return USB_TRANSFER_ERROR;
   }
 }
 
+// This function dispatches a completed transfer to its handle.
+// It is called from UsbEventDispatcher using libusb_handle_events_timeout.
 static void LIBUSB_CALL HandleTransferCompletion(
     struct libusb_transfer* transfer) {
-  UsbDevice* const device = reinterpret_cast<UsbDevice*>(transfer->user_data);
+  UsbDeviceHandle* const device =
+      reinterpret_cast<UsbDeviceHandle*>(transfer->user_data);
+
   device->TransferComplete(transfer);
+  libusb_free_transfer(transfer);
 }
 
 }  // namespace
 
-UsbDevice::Transfer::Transfer() : length(0) {}
+UsbDeviceHandle::Transfer::Transfer()
+    : transfer_type(USB_TRANSFER_CONTROL), length(0) {}
 
-UsbDevice::Transfer::~Transfer() {}
+UsbDeviceHandle::Transfer::~Transfer() {}
 
-UsbDevice::UsbDevice(UsbService* service, PlatformUsbDeviceHandle handle)
-    : service_(service), handle_(handle) {
+UsbDeviceHandle::UsbDeviceHandle(UsbService* service,
+                                 int device,
+                                 PlatformUsbDeviceHandle handle)
+    : service_(service), device_(device), handle_(handle) {
   DCHECK(handle) << "Cannot create device with NULL handle.";
 }
 
-UsbDevice::UsbDevice() : service_(NULL), handle_(NULL) {}
-
-UsbDevice::~UsbDevice() {}
-
-void UsbDevice::Close(const base::Callback<void()>& callback) {
-  CheckDevice();
-  service_->CloseDevice(this);
-  handle_ = NULL;
-  callback.Run();
+UsbDeviceHandle::UsbDeviceHandle()
+    : service_(NULL), device_(0), handle_(NULL) {
 }
 
-void UsbDevice::TransferComplete(PlatformUsbTransferHandle handle) {
-  base::AutoLock lock(lock_);
+UsbDeviceHandle::~UsbDeviceHandle() {
+  InternalClose();
+}
 
-  // TODO(gdk): Handle device disconnect.
-  DCHECK(ContainsKey(transfers_, handle)) << "Missing transfer completed";
-  Transfer* const transfer = &transfers_[handle];
+void UsbDeviceHandle::Close(const base::Callback<void()>& callback) {
+  if (handle_ == 0)
+    return;
+  BrowserThread::PostTask(
+      BrowserThread::FILE,
+      FROM_HERE,
+      base::Bind(&UsbService::CloseDeviceHandle,
+                 base::Unretained(service_),
+                 make_scoped_refptr(this),
+                 callback));
+}
+
+void UsbDeviceHandle::TransferComplete(PlatformUsbTransferHandle handle) {
+  Transfer transfer;
+  base::AutoLock handle_guard(handle_lock_);
+  // If handle->user_data is cleared after we obtained it, the handles will be
+  // removed and callbacks is already called in InternalClose. This case we can
+  // simply return.
+  if (handle->user_data == NULL)
+    return;
+
+  {
+    base::AutoLock guard(transfer_lock_);
+    transfer = transfers_[handle];
+    transfers_.erase(handle);
+  }
+
+  CHECK_DEVICE(transfer.callback,
+               USB_TRANSFER_DISCONNECT,
+               scoped_refptr<net::IOBuffer>(), 0);
+
+  if (handle->status != LIBUSB_TRANSFER_COMPLETED &&
+      handle->status != LIBUSB_TRANSFER_CANCELLED) {
+    service_->ScheduleEnumerateDevice();
+  }
 
   DCHECK(handle->actual_length >= 0) << "Negative actual length received";
   size_t actual_length =
       static_cast<size_t>(std::max(handle->actual_length, 0));
 
-  DCHECK(transfer->length >= actual_length) <<
+  DCHECK(transfer.length >= actual_length) <<
       "data too big for our buffer (libusb failure?)";
 
-  scoped_refptr<net::IOBuffer> buffer = transfer->buffer;
-  switch (transfer->transfer_type) {
+  scoped_refptr<net::IOBuffer> buffer = transfer.buffer;
+  switch (transfer.transfer_type) {
     case USB_TRANSFER_CONTROL:
       // If the transfer is a control transfer we do not expose the control
       // setup header to the caller. This logic strips off the header if
       // present before invoking the callback provided with the transfer.
       if (actual_length > 0) {
-        CHECK(transfer->length >= LIBUSB_CONTROL_SETUP_SIZE) <<
+        CHECK(transfer.length >= LIBUSB_CONTROL_SETUP_SIZE) <<
             "buffer was not correctly set: too small for the control header";
 
-        if (transfer->length >= actual_length &&
+        if (transfer.length >= actual_length &&
             actual_length >= LIBUSB_CONTROL_SETUP_SIZE) {
           // If the payload is zero bytes long, pad out the allocated buffer
           // size to one byte so that an IOBuffer of that size can be allocated.
           scoped_refptr<net::IOBuffer> resized_buffer = new net::IOBuffer(
               std::max(actual_length, static_cast<size_t>(1)));
           memcpy(resized_buffer->data(),
                  buffer->data() + LIBUSB_CONTROL_SETUP_SIZE,
                  actual_length);
           buffer = resized_buffer;
         }
       }
       break;
 
     case USB_TRANSFER_ISOCHRONOUS:
       // Isochronous replies might carry data in the different isoc packets even
       // if the transfer actual_data value is zero. Furthermore, not all of the
       // received packets might contain data, so we need to calculate how many
       // data bytes we are effectively providing and pack the results.
       if (actual_length == 0) {
         size_t packet_buffer_start = 0;
         for (int i = 0; i < handle->num_iso_packets; ++i) {
           PlatformUsbIsoPacketDescriptor packet = &handle->iso_packet_desc[i];
           if (packet->actual_length > 0) {
             // We don't need to copy as long as all packets until now provide
             // all the data the packet can hold.
             if (actual_length < packet_buffer_start) {
               CHECK(packet_buffer_start + packet->actual_length <=
-                    transfer->length);
+                    transfer.length);
               memmove(buffer->data() + actual_length,
                       buffer->data() + packet_buffer_start,
                       packet->actual_length);
             }
             actual_length += packet->actual_length;
           }
 
           packet_buffer_start += packet->length;
         }
       }
       break;
 
     case USB_TRANSFER_BULK:
     case USB_TRANSFER_INTERRUPT:
       break;
 
     default:
       NOTREACHED() << "Invalid usb transfer type";
   }
 
-  transfer->callback.Run(ConvertTransferStatus(handle->status), buffer,
-                         actual_length);
-
-  transfers_.erase(handle);
-  libusb_free_transfer(handle);
+  transfer.callback.Run(ConvertTransferStatus(handle->status), buffer,
+                        actual_length);
 }
 
-void UsbDevice::ListInterfaces(UsbConfigDescriptor* config,
-                               const UsbInterfaceCallback& callback) {
-  CheckDevice();
+void UsbDeviceHandle::ListInterfaces(UsbConfigDescriptor* config,
+                                     const UsbInterfaceCallback& callback) {
+  CHECK_DEVICE(callback, false);
 
   PlatformUsbDevice device = libusb_get_device(handle_);
 
   PlatformUsbConfigDescriptor platform_config;
   const int list_result = libusb_get_active_config_descriptor(device,
       &platform_config);
   if (list_result == 0) {
     config->Reset(platform_config);
   }
   callback.Run(list_result == 0);
 }
 
-void UsbDevice::ClaimInterface(const int interface_number,
-                               const UsbInterfaceCallback& callback) {
-  CheckDevice();
+void UsbDeviceHandle::ClaimInterface(const int interface_number,
+                                     const UsbInterfaceCallback& callback) {
+  CHECK_DEVICE(callback, false);
 
   const int claim_result = libusb_claim_interface(handle_, interface_number);
   callback.Run(claim_result == 0);
 }
 
-void UsbDevice::ReleaseInterface(const int interface_number,
+void UsbDeviceHandle::ReleaseInterface(const int interface_number,
                                  const UsbInterfaceCallback& callback) {
-  CheckDevice();
+  CHECK_DEVICE(callback, false);
 
   const int release_result = libusb_release_interface(handle_,
                                                       interface_number);
   callback.Run(release_result == 0);
 }
 
-void UsbDevice::SetInterfaceAlternateSetting(
+void UsbDeviceHandle::SetInterfaceAlternateSetting(
     const int interface_number,
     const int alternate_setting,
     const UsbInterfaceCallback& callback) {
-  CheckDevice();
+  CHECK_DEVICE(callback, false);
 
   const int setting_result = libusb_set_interface_alt_setting(handle_,
       interface_number, alternate_setting);
 
   callback.Run(setting_result == 0);
 }
 
-void UsbDevice::ControlTransfer(const UsbEndpointDirection direction,
+void UsbDeviceHandle::ControlTransfer(const UsbEndpointDirection 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 UsbTransferCallback& callback) {
-  CheckDevice();
+  CHECK_DEVICE(callback, USB_TRANSFER_DISCONNECT,
+               scoped_refptr<net::IOBuffer>(), 0);
 
   const size_t resized_length = LIBUSB_CONTROL_SETUP_SIZE + length;
   scoped_refptr<net::IOBuffer> resized_buffer(new net::IOBufferWithSize(
       resized_length));
   memcpy(resized_buffer->data() + LIBUSB_CONTROL_SETUP_SIZE, buffer->data(),
          length);
 
   struct libusb_transfer* const transfer = libusb_alloc_transfer(0);
   const uint8 converted_type = CreateRequestType(direction, request_type,
                                                  recipient);
   libusb_fill_control_setup(reinterpret_cast<uint8*>(resized_buffer->data()),
                             converted_type, request, value, index, length);
   libusb_fill_control_transfer(transfer, handle_, reinterpret_cast<uint8*>(
       resized_buffer->data()), HandleTransferCompletion, this, timeout);
   SubmitTransfer(transfer,
                  USB_TRANSFER_CONTROL,
                  resized_buffer.get(),
                  resized_length,
                  callback);
 }
 
-void UsbDevice::BulkTransfer(const UsbEndpointDirection direction,
+void UsbDeviceHandle::BulkTransfer(const UsbEndpointDirection direction,
     const uint8 endpoint, net::IOBuffer* buffer, const size_t length,
     const unsigned int timeout, const UsbTransferCallback& callback) {
-  CheckDevice();
+  CHECK_DEVICE(callback, USB_TRANSFER_DISCONNECT,
+               scoped_refptr<net::IOBuffer>(), 0);
 
   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<uint8*>(buffer->data()), length,
       HandleTransferCompletion, this, timeout);
   SubmitTransfer(transfer, USB_TRANSFER_BULK, buffer, length, callback);
 }
 
-void UsbDevice::InterruptTransfer(const UsbEndpointDirection direction,
+void UsbDeviceHandle::InterruptTransfer(const UsbEndpointDirection direction,
     const uint8 endpoint, net::IOBuffer* buffer, const size_t length,
     const unsigned int timeout, const UsbTransferCallback& callback) {
-  CheckDevice();
+  CHECK_DEVICE(callback, USB_TRANSFER_DISCONNECT,
+               scoped_refptr<net::IOBuffer>(), 0);
 
   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<uint8*>(buffer->data()), length,
       HandleTransferCompletion, this, timeout);
   SubmitTransfer(transfer, USB_TRANSFER_INTERRUPT, buffer, length, callback);
 }
 
-void UsbDevice::IsochronousTransfer(const UsbEndpointDirection direction,
+void UsbDeviceHandle::IsochronousTransfer(const UsbEndpointDirection direction,
     const uint8 endpoint, net::IOBuffer* buffer, const size_t length,
     const unsigned int packets, const unsigned int packet_length,
     const unsigned int timeout, const UsbTransferCallback& callback) {
-  CheckDevice();
+  CHECK_DEVICE(callback, USB_TRANSFER_DISCONNECT,
+               scoped_refptr<net::IOBuffer>(), 0);
 
   const uint64 total_length = packets * packet_length;
   CHECK(packets <= length && total_length <= length) <<
       "transfer length is too small";
 
   struct libusb_transfer* const transfer = libusb_alloc_transfer(packets);
   const uint8 new_endpoint = ConvertTransferDirection(direction) | endpoint;
   libusb_fill_iso_transfer(transfer, handle_, new_endpoint,
       reinterpret_cast<uint8*>(buffer->data()), length, packets,
       HandleTransferCompletion, this, timeout);
   libusb_set_iso_packet_lengths(transfer, packet_length);
 
   SubmitTransfer(transfer, USB_TRANSFER_ISOCHRONOUS, buffer, length, callback);
 }
 
-void UsbDevice::ResetDevice(const base::Callback<void(bool)>& callback) {
-  CheckDevice();
+void UsbDeviceHandle::ResetDevice(const base::Callback<void(bool)>& callback) {
+  // Blocking operation. Run it on the FILE thread.
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
+  CHECK_DEVICE(callback, false);
   callback.Run(libusb_reset_device(handle_) == 0);
 }
 
-void UsbDevice::CheckDevice() {
-  DCHECK(handle_) << "Device is already closed.";
+void UsbDeviceHandle::InternalClose() {
+  base::AutoLock handle_guard(handle_lock_);
+  base::AutoLock guard(transfer_lock_);
+  if (handle_ == NULL)
+    return;
+
+  // Cancel all the transfers.
+  for (std::map<PlatformUsbTransferHandle, Transfer>::iterator it
+      = transfers_.begin(); it != transfers_.end(); it++) {
+    it->first->user_data = NULL;
+    it->second.callback.Run(USB_TRANSFER_DISCONNECT,
+                            scoped_refptr<net::IOBuffer>(), 0);
+  }
+  transfers_.clear();
+  libusb_close(handle_);
+  handle_ = NULL;
 }
 
-void UsbDevice::SubmitTransfer(PlatformUsbTransferHandle handle,
-                               UsbTransferType transfer_type,
-                               net::IOBuffer* buffer,
-                               const size_t length,
-                               const UsbTransferCallback& callback) {
+void UsbDeviceHandle::SubmitTransfer(PlatformUsbTransferHandle handle,
+                                     UsbTransferType transfer_type,
+                                     net::IOBuffer* buffer,
+                                     const size_t length,
+                                     const UsbTransferCallback& callback) {
+  base::AutoLock lock(transfer_lock_);
+  // This check must be done after the lock.
+  if (!handle_)
+    return;
+
   Transfer transfer;
   transfer.transfer_type = transfer_type;
   transfer.buffer = buffer;
   transfer.length = length;
   transfer.callback = callback;
 
-  {
-    base::AutoLock lock(lock_);
-    transfers_[handle] = transfer;
-    libusb_submit_transfer(handle);
-  }
+  transfers_[handle] = transfer;
+  libusb_submit_transfer(handle);
 }