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+/*
+ * Synchronous I/O functions for libusb
+ * Copyright (C) 2007-2008 Daniel Drake <dsd@gentoo.org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <config.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "libusbi.h"
+
+/**
+ * @defgroup syncio Synchronous device I/O
+ *
+ * This page documents libusb's synchronous (blocking) API for USB device I/O.
+ * This interface is easy to use but has some limitations. More advanced users
+ * may wish to consider using the \ref asyncio "asynchronous I/O API" instead.
+ */
+
+static void LIBUSB_CALL ctrl_transfer_cb(struct libusb_transfer *transfer)
+{
+ int *completed = transfer->user_data;
+ *completed = 1;
+ usbi_dbg("actual_length=%d", transfer->actual_length);
+ /* caller interprets result and frees transfer */
+}
+
+/** \ingroup syncio
+ * Perform a USB control transfer.
+ *
+ * The direction of the transfer is inferred from the bmRequestType field of
+ * the setup packet.
+ *
+ * The wValue, wIndex and wLength fields values should be given in host-endian
+ * byte order.
+ *
+ * \param dev_handle a handle for the device to communicate with
+ * \param bmRequestType the request type field for the setup packet
+ * \param bRequest the request field for the setup packet
+ * \param wValue the value field for the setup packet
+ * \param wIndex the index field for the setup packet
+ * \param data a suitably-sized data buffer for either input or output
+ * (depending on direction bits within bmRequestType)
+ * \param wLength the length field for the setup packet. The data buffer should
+ * be at least this size.
+ * \param timeout timeout (in millseconds) that this function should wait
+ * before giving up due to no response being received. For an unlimited
+ * timeout, use value 0.
+ * \returns on success, the number of bytes actually transferred
+ * \returns LIBUSB_ERROR_TIMEOUT if the transfer timed out
+ * \returns LIBUSB_ERROR_PIPE if the control request was not supported by the
+ * device
+ * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
+ * \returns another LIBUSB_ERROR code on other failures
+ */
+int API_EXPORTED libusb_control_transfer(libusb_device_handle *dev_handle,
+ uint8_t bmRequestType, uint8_t bRequest, uint16_t wValue, uint16_t wIndex,
+ unsigned char *data, uint16_t wLength, unsigned int timeout)
+{
+ struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+ unsigned char *buffer;
+ int completed = 0;
+ int r;
+
+ if (!transfer)
+ return LIBUSB_ERROR_NO_MEM;
+
+ buffer = malloc(LIBUSB_CONTROL_SETUP_SIZE + wLength);
+ if (!buffer) {
+ libusb_free_transfer(transfer);
+ return LIBUSB_ERROR_NO_MEM;
+ }
+
+ libusb_fill_control_setup(buffer, bmRequestType, bRequest, wValue, wIndex,
+ wLength);
+ if ((bmRequestType & LIBUSB_ENDPOINT_DIR_MASK) == LIBUSB_ENDPOINT_OUT)
+ memcpy(buffer + LIBUSB_CONTROL_SETUP_SIZE, data, wLength);
+
+ libusb_fill_control_transfer(transfer, dev_handle, buffer,
+ ctrl_transfer_cb, &completed, timeout);
+ transfer->flags = LIBUSB_TRANSFER_FREE_BUFFER;
+ r = libusb_submit_transfer(transfer);
+ if (r < 0) {
+ libusb_free_transfer(transfer);
+ return r;
+ }
+
+ while (!completed) {
+ r = libusb_handle_events_check(HANDLE_CTX(dev_handle), &completed);
+ if (r < 0) {
+ if (r == LIBUSB_ERROR_INTERRUPTED)
+ continue;
+ libusb_cancel_transfer(transfer);
+ while (!completed)
+ if (libusb_handle_events_check(HANDLE_CTX(dev_handle), &completed) < 0)
+ break;
+ libusb_free_transfer(transfer);
+ return r;
+ }
+ }
+
+ if ((bmRequestType & LIBUSB_ENDPOINT_DIR_MASK) == LIBUSB_ENDPOINT_IN)
+ memcpy(data, libusb_control_transfer_get_data(transfer),
+ transfer->actual_length);
+
+ switch (transfer->status) {
+ case LIBUSB_TRANSFER_COMPLETED:
+ r = transfer->actual_length;
+ break;
+ case LIBUSB_TRANSFER_TIMED_OUT:
+ r = LIBUSB_ERROR_TIMEOUT;
+ break;
+ case LIBUSB_TRANSFER_STALL:
+ r = LIBUSB_ERROR_PIPE;
+ break;
+ case LIBUSB_TRANSFER_NO_DEVICE:
+ r = LIBUSB_ERROR_NO_DEVICE;
+ break;
+ default:
+ usbi_warn(HANDLE_CTX(dev_handle),
+ "unrecognised status code %d", transfer->status);
+ r = LIBUSB_ERROR_OTHER;
+ }
+
+ libusb_free_transfer(transfer);
+ return r;
+}
+
+static void LIBUSB_CALL bulk_transfer_cb(struct libusb_transfer *transfer)
+{
+ int *completed = transfer->user_data;
+ *completed = 1;
+ usbi_dbg("actual_length=%d", transfer->actual_length);
+ /* caller interprets results and frees transfer */
+}
+
+static int do_sync_bulk_transfer(struct libusb_device_handle *dev_handle,
+ unsigned char endpoint, unsigned char *buffer, int length,
+ int *transferred, unsigned int timeout, unsigned char type)
+{
+ struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+ int completed = 0;
+ int r;
+
+ if (!transfer)
+ return LIBUSB_ERROR_NO_MEM;
+
+ libusb_fill_bulk_transfer(transfer, dev_handle, endpoint, buffer, length,
+ bulk_transfer_cb, &completed, timeout);
+ transfer->type = type;
+
+ r = libusb_submit_transfer(transfer);
+ if (r < 0) {
+ libusb_free_transfer(transfer);
+ return r;
+ }
+
+ while (!completed) {
+ r = libusb_handle_events_check(HANDLE_CTX(dev_handle), &completed);
+ if (r < 0) {
+ if (r == LIBUSB_ERROR_INTERRUPTED)
+ continue;
+ libusb_cancel_transfer(transfer);
+ while (!completed)
+ if (libusb_handle_events_check(HANDLE_CTX(dev_handle), &completed) < 0)
+ break;
+ libusb_free_transfer(transfer);
+ return r;
+ }
+ }
+
+ *transferred = transfer->actual_length;
+ switch (transfer->status) {
+ case LIBUSB_TRANSFER_COMPLETED:
+ r = 0;
+ break;
+ case LIBUSB_TRANSFER_TIMED_OUT:
+ r = LIBUSB_ERROR_TIMEOUT;
+ break;
+ case LIBUSB_TRANSFER_STALL:
+ r = LIBUSB_ERROR_PIPE;
+ break;
+ case LIBUSB_TRANSFER_OVERFLOW:
+ r = LIBUSB_ERROR_OVERFLOW;
+ break;
+ case LIBUSB_TRANSFER_NO_DEVICE:
+ r = LIBUSB_ERROR_NO_DEVICE;
+ break;
+ default:
+ usbi_warn(HANDLE_CTX(dev_handle),
+ "unrecognised status code %d", transfer->status);
+ r = LIBUSB_ERROR_OTHER;
+ }
+
+ libusb_free_transfer(transfer);
+ return r;
+}
+
+/** \ingroup syncio
+ * Perform a USB bulk transfer. The direction of the transfer is inferred from
+ * the direction bits of the endpoint address.
+ *
+ * For bulk reads, the <tt>length</tt> field indicates the maximum length of
+ * data you are expecting to receive. If less data arrives than expected,
+ * this function will return that data, so be sure to check the
+ * <tt>transferred</tt> output parameter.
+ *
+ * You should also check the <tt>transferred</tt> parameter for bulk writes.
+ * Not all of the data may have been written.
+ *
+ * Also check <tt>transferred</tt> when dealing with a timeout error code.
+ * libusb may have to split your transfer into a number of chunks to satisfy
+ * underlying O/S requirements, meaning that the timeout may expire after
+ * the first few chunks have completed. libusb is careful not to lose any data
+ * that may have been transferred; do not assume that timeout conditions
+ * indicate a complete lack of I/O.
+ *
+ * \param dev_handle a handle for the device to communicate with
+ * \param endpoint the address of a valid endpoint to communicate with
+ * \param data a suitably-sized data buffer for either input or output
+ * (depending on endpoint)
+ * \param length for bulk writes, the number of bytes from data to be sent. for
+ * bulk reads, the maximum number of bytes to receive into the data buffer.
+ * \param transferred output location for the number of bytes actually
+ * transferred.
+ * \param timeout timeout (in millseconds) that this function should wait
+ * before giving up due to no response being received. For an unlimited
+ * timeout, use value 0.
+ *
+ * \returns 0 on success (and populates <tt>transferred</tt>)
+ * \returns LIBUSB_ERROR_TIMEOUT if the transfer timed out (and populates
+ * <tt>transferred</tt>)
+ * \returns LIBUSB_ERROR_PIPE if the endpoint halted
+ * \returns LIBUSB_ERROR_OVERFLOW if the device offered more data, see
+ * \ref packetoverflow
+ * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
+ * \returns another LIBUSB_ERROR code on other failures
+ */
+int API_EXPORTED libusb_bulk_transfer(struct libusb_device_handle *dev_handle,
+ unsigned char endpoint, unsigned char *data, int length, int *transferred,
+ unsigned int timeout)
+{
+ return do_sync_bulk_transfer(dev_handle, endpoint, data, length,
+ transferred, timeout, LIBUSB_TRANSFER_TYPE_BULK);
+}
+
+/** \ingroup syncio
+ * Perform a USB interrupt transfer. The direction of the transfer is inferred
+ * from the direction bits of the endpoint address.
+ *
+ * For interrupt reads, the <tt>length</tt> field indicates the maximum length
+ * of data you are expecting to receive. If less data arrives than expected,
+ * this function will return that data, so be sure to check the
+ * <tt>transferred</tt> output parameter.
+ *
+ * You should also check the <tt>transferred</tt> parameter for interrupt
+ * writes. Not all of the data may have been written.
+ *
+ * Also check <tt>transferred</tt> when dealing with a timeout error code.
+ * libusb may have to split your transfer into a number of chunks to satisfy
+ * underlying O/S requirements, meaning that the timeout may expire after
+ * the first few chunks have completed. libusb is careful not to lose any data
+ * that may have been transferred; do not assume that timeout conditions
+ * indicate a complete lack of I/O.
+ *
+ * The default endpoint bInterval value is used as the polling interval.
+ *
+ * \param dev_handle a handle for the device to communicate with
+ * \param endpoint the address of a valid endpoint to communicate with
+ * \param data a suitably-sized data buffer for either input or output
+ * (depending on endpoint)
+ * \param length for bulk writes, the number of bytes from data to be sent. for
+ * bulk reads, the maximum number of bytes to receive into the data buffer.
+ * \param transferred output location for the number of bytes actually
+ * transferred.
+ * \param timeout timeout (in millseconds) that this function should wait
+ * before giving up due to no response being received. For an unlimited
+ * timeout, use value 0.
+ *
+ * \returns 0 on success (and populates <tt>transferred</tt>)
+ * \returns LIBUSB_ERROR_TIMEOUT if the transfer timed out
+ * \returns LIBUSB_ERROR_PIPE if the endpoint halted
+ * \returns LIBUSB_ERROR_OVERFLOW if the device offered more data, see
+ * \ref packetoverflow
+ * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
+ * \returns another LIBUSB_ERROR code on other error
+ */
+int API_EXPORTED libusb_interrupt_transfer(
+ struct libusb_device_handle *dev_handle, unsigned char endpoint,
+ unsigned char *data, int length, int *transferred, unsigned int timeout)
+{
+ return do_sync_bulk_transfer(dev_handle, endpoint, data, length,
+ transferred, timeout, LIBUSB_TRANSFER_TYPE_INTERRUPT);
+}