/*********************************************************************
 *********************************************************************/
/*********************************************************************
 * modified some function to avoid crash, support Android
 * Copyright (C) 2014-2016 saki@serenegiant All rights reserved.
 *********************************************************************/
/*********************************************************************
 * Software License Agreement (BSD License)
 *
 *  Copyright (C) 2010-2012 Ken Tossell
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials provided
 *     with the distribution.
 *   * Neither the name of the author nor other contributors may be
 *     used to endorse or promote products derived from this software
 *     without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 *********************************************************************/
/**
 * @defgroup streaming Streaming control functions
 * @brief Tools for creating, managing and consuming video streams
 */

#define LOCAL_DEBUG 0

#define LOG_TAG "libuvc/stream"
#if 1	// デバッグ情報を出さない時1
	#ifndef LOG_NDEBUG
		#define	LOG_NDEBUG		// LOGV/LOGD/MARKを出力しない時
		#endif
	#undef USE_LOGALL			// 指定したLOGxだけを出力
#else
	#define USE_LOGALL
	#undef LOG_NDEBUG
	#undef NDEBUG
	#define GET_RAW_DESCRIPTOR
#endif

#include <assert.h>		// XXX add assert for debugging

#include "libuvc/libuvc.h"
#include "libuvc/libuvc_internal.h"
#include <errno.h>

uvc_frame_desc_t *uvc_find_frame_desc_stream(uvc_stream_handle_t *strmh,
		uint16_t format_id, uint16_t frame_id);
uvc_frame_desc_t *uvc_find_frame_desc(uvc_device_handle_t *devh,
		uint16_t format_id, uint16_t frame_id);
static void *_uvc_user_caller(void *arg);
static void _uvc_populate_frame(uvc_stream_handle_t *strmh);

struct format_table_entry {
	enum uvc_frame_format format;
	uint8_t abstract_fmt;
	uint8_t guid[16];
	int children_count;
	enum uvc_frame_format *children;
};

struct timespec ts;
struct timeval tv;

struct format_table_entry *_get_format_entry(enum uvc_frame_format format) {
#define ABS_FMT(_fmt, ...) \
    case _fmt: { \
    static enum uvc_frame_format _fmt##_children[] = __VA_ARGS__; \
    static struct format_table_entry _fmt##_entry = { \
      _fmt, 0, {}, ARRAYSIZE(_fmt##_children), _fmt##_children }; \
    return &_fmt##_entry; }

#define FMT(_fmt, ...) \
    case _fmt: { \
    static struct format_table_entry _fmt##_entry = { \
      _fmt, 0, __VA_ARGS__, 0, NULL }; \
    return &_fmt##_entry; }

	switch (format) {
	/* Define new formats here */
	ABS_FMT(UVC_FRAME_FORMAT_ANY,
		{UVC_FRAME_FORMAT_UNCOMPRESSED, UVC_FRAME_FORMAT_COMPRESSED})

	ABS_FMT(UVC_FRAME_FORMAT_UNCOMPRESSED,
		{UVC_FRAME_FORMAT_YUYV, UVC_FRAME_FORMAT_UYVY, UVC_FRAME_FORMAT_GRAY8})
	FMT(UVC_FRAME_FORMAT_YUYV,
		{'Y', 'U', 'Y', '2', 0x00, 0x00, 0x10, 0x00, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71})
	FMT(UVC_FRAME_FORMAT_UYVY,
		{'U', 'Y', 'V', 'Y', 0x00, 0x00, 0x10, 0x00, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71})
	FMT(UVC_FRAME_FORMAT_GRAY8,
		{'Y', '8', '0', '0', 0x00, 0x00, 0x10, 0x00, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71})
    FMT(UVC_FRAME_FORMAT_BY8,
    	{'B', 'Y', '8', ' ', 0x00, 0x00, 0x10, 0x00, 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71})

	ABS_FMT(UVC_FRAME_FORMAT_COMPRESSED,
		{UVC_FRAME_FORMAT_MJPEG})
	FMT(UVC_FRAME_FORMAT_MJPEG,
		{'M', 'J', 'P', 'G'})

	default:
		return NULL;
	}

#undef ABS_FMT
#undef FMT
}

static uint8_t _uvc_frame_format_matches_guid(enum uvc_frame_format fmt,
		uint8_t guid[16]) {
	struct format_table_entry *format;
	int child_idx;

	format = _get_format_entry(fmt);
	if (UNLIKELY(!format))
		return 0;

	if (!format->abstract_fmt && !memcmp(guid, format->guid, 16))
		return 1;

	for (child_idx = 0; child_idx < format->children_count; child_idx++) {
		if (_uvc_frame_format_matches_guid(format->children[child_idx], guid))
			return 1;
	}

	return 0;
}

static enum uvc_frame_format uvc_frame_format_for_guid(uint8_t guid[16]) {
	struct format_table_entry *format;
	enum uvc_frame_format fmt;

	for (fmt = 0; fmt < UVC_FRAME_FORMAT_COUNT; ++fmt) {
		format = _get_format_entry(fmt);
		if (!format || format->abstract_fmt)
			continue;
		if (!memcmp(format->guid, guid, 16))
			return format->format;
	}

	return UVC_FRAME_FORMAT_UNKNOWN;
}

/** @internal
 * Run a streaming control query
 * @param[in] devh UVC device
 * @param[in,out] ctrl Control block
 * @param[in] probe Whether this is a probe query or a commit query
 * @param[in] req Query type
 */
uvc_error_t uvc_query_stream_ctrl(uvc_device_handle_t *devh,
		uvc_stream_ctrl_t *ctrl, uint8_t probe, enum uvc_req_code req) {
	uint8_t buf[48];	// XXX support UVC 1.1 & 1.5
	size_t len;
	uvc_error_t err;

	memset(buf, 0, sizeof(buf));	// bzero(buf, sizeof(buf));	// bzero is deprecated

	const uint16_t bcdUVC = devh->info->ctrl_if.bcdUVC;
	if (bcdUVC >= 0x0150)
		len = 48;
	else if (bcdUVC >= 0x0110)
		len = 34;
	else
		len = 26;
//	LOGI("bcdUVC:%x,req:0x%02x,probe:%d", bcdUVC, req, probe);
	/* prepare for a SET transfer */
	if (req == UVC_SET_CUR) {
		SHORT_TO_SW(ctrl->bmHint, buf);
		buf[2] = ctrl->bFormatIndex;
		buf[3] = ctrl->bFrameIndex;
		INT_TO_DW(ctrl->dwFrameInterval, buf + 4);
		SHORT_TO_SW(ctrl->wKeyFrameRate, buf + 8);
		SHORT_TO_SW(ctrl->wPFrameRate, buf + 10);
		SHORT_TO_SW(ctrl->wCompQuality, buf + 12);
		SHORT_TO_SW(ctrl->wCompWindowSize, buf + 14);
		SHORT_TO_SW(ctrl->wDelay, buf + 16);
		INT_TO_DW(ctrl->dwMaxVideoFrameSize, buf + 18);
		INT_TO_DW(ctrl->dwMaxPayloadTransferSize, buf + 22);

		if (len > 26) {	// len == 34
			// XXX add to support UVC 1.1
			INT_TO_DW(ctrl->dwClockFrequency, buf + 26);
			buf[30] = ctrl->bmFramingInfo;
			buf[31] = ctrl->bPreferedVersion;
			buf[32] = ctrl->bMinVersion;
			buf[33] = ctrl->bMaxVersion;
			if (len == 48) {
				// XXX add to support UVC1.5
				buf[34] = ctrl->bUsage;
				buf[35] = ctrl->bBitDepthLuma;
				buf[36] = ctrl->bmSettings;
				buf[37] = ctrl->bMaxNumberOfRefFramesPlus1;
				SHORT_TO_SW(ctrl->bmRateControlModes, buf + 38);
				LONG_TO_QW(ctrl->bmLayoutPerStream, buf + 40);
			}
		}
	}

	/* do the transfer */
	err = libusb_control_transfer(devh->usb_devh,
			req == UVC_SET_CUR ? 0x21 : 0xA1, req,
			probe ? (UVC_VS_PROBE_CONTROL << 8) : (UVC_VS_COMMIT_CONTROL << 8),
			ctrl->bInterfaceNumber, buf, len, 0);

	if (UNLIKELY(err <= 0)) {
		// when libusb_control_transfer returned error or transfer bytes was zero.
		if (!err) {
			UVC_DEBUG("libusb_control_transfer transfered zero length data");
			err = UVC_ERROR_OTHER;
		}
		return err;
	}
	if (err < len) {
#if !defined(__LP64__)
		LOGE("transfered bytes is smaller than data bytes:%d expected %d", err, len);
#else
		LOGE("transfered bytes is smaller than data bytes:%d expected %ld", err, len);
#endif
		return UVC_ERROR_OTHER;
	}
	/* now decode following a GET transfer */
	if (req != UVC_SET_CUR) {
		ctrl->bmHint = SW_TO_SHORT(buf);
		ctrl->bFormatIndex = buf[2];
		ctrl->bFrameIndex = buf[3];
		ctrl->dwFrameInterval = DW_TO_INT(buf + 4);
		ctrl->wKeyFrameRate = SW_TO_SHORT(buf + 8);
		ctrl->wPFrameRate = SW_TO_SHORT(buf + 10);
		ctrl->wCompQuality = SW_TO_SHORT(buf + 12);
		ctrl->wCompWindowSize = SW_TO_SHORT(buf + 14);
		ctrl->wDelay = SW_TO_SHORT(buf + 16);
		ctrl->dwMaxVideoFrameSize = DW_TO_INT(buf + 18);
		ctrl->dwMaxPayloadTransferSize = DW_TO_INT(buf + 22);

		if (len > 26) {	// len == 34
			// XXX add to support UVC 1.1
			ctrl->dwClockFrequency = DW_TO_INT(buf + 26);
			ctrl->bmFramingInfo = buf[30];
			ctrl->bPreferedVersion = buf[31];
			ctrl->bMinVersion = buf[32];
			ctrl->bMaxVersion = buf[33];
			if (len >= 48) {
				// XXX add to support UVC1.5
				ctrl->bUsage = buf[34];
				ctrl->bBitDepthLuma = buf[35];
				ctrl->bmSettings = buf[36];
				ctrl->bMaxNumberOfRefFramesPlus1 = buf[37];
				ctrl->bmRateControlModes = SW_TO_SHORT(buf + 38);
				ctrl->bmLayoutPerStream = QW_TO_LONG(buf + 40);
			}
		}

		/* fix up block for cameras that fail to set dwMax */
		if (!ctrl->dwMaxVideoFrameSize) {
			LOGW("fix up block for cameras that fail to set dwMax");
			uvc_frame_desc_t *frame_desc = uvc_find_frame_desc(devh,
					ctrl->bFormatIndex, ctrl->bFrameIndex);

			if (frame_desc) {
				ctrl->dwMaxVideoFrameSize = frame_desc->dwMaxVideoFrameBufferSize;
			}
		}
	}

	return UVC_SUCCESS;
}

/** @brief Reconfigure stream with a new stream format.
 * @ingroup streaming
 *
 * This may be executed whether or not the stream is running.
 *
 * @param[in] strmh Stream handle
 * @param[in] ctrl Control block, processed using {uvc_probe_stream_ctrl} or
 *             {uvc_get_stream_ctrl_format_size}
 */
uvc_error_t uvc_stream_ctrl(uvc_stream_handle_t *strmh, uvc_stream_ctrl_t *ctrl) {
	uvc_error_t ret;

	if (UNLIKELY(strmh->stream_if->bInterfaceNumber != ctrl->bInterfaceNumber))
		return UVC_ERROR_INVALID_PARAM;

	/* @todo Allow the stream to be modified without restarting the stream */
	if (UNLIKELY(strmh->running))
		return UVC_ERROR_BUSY;

	ret = uvc_query_stream_ctrl(strmh->devh, ctrl, 0, UVC_SET_CUR);	// commit query
	if (UNLIKELY(ret != UVC_SUCCESS))
		return ret;

	strmh->cur_ctrl = *ctrl;
	return UVC_SUCCESS;
}

/** @internal
 * @brief Find the descriptor for a specific frame configuration
 * @param stream_if Stream interface
 * @param format_id Index of format class descriptor
 * @param frame_id Index of frame descriptor
 */
static uvc_frame_desc_t *_uvc_find_frame_desc_stream_if(
		uvc_streaming_interface_t *stream_if, uint16_t format_id,
		uint16_t frame_id) {

	uvc_format_desc_t *format = NULL;
	uvc_frame_desc_t *frame = NULL;

	DL_FOREACH(stream_if->format_descs, format)
	{
		if (format->bFormatIndex == format_id) {
			DL_FOREACH(format->frame_descs, frame)
			{
				if (frame->bFrameIndex == frame_id)
					return frame;
			}
		}
	}

	return NULL ;
}

uvc_error_t uvc_get_frame_desc(uvc_device_handle_t *devh,
		uvc_stream_ctrl_t *ctrl, uvc_frame_desc_t **desc) {

	*desc = uvc_find_frame_desc(devh, ctrl->bFormatIndex, ctrl->bFrameIndex);
	return *desc ? UVC_SUCCESS : UVC_ERROR_INVALID_PARAM;
}

uvc_frame_desc_t *uvc_find_frame_desc_stream(uvc_stream_handle_t *strmh,
		uint16_t format_id, uint16_t frame_id) {
	return _uvc_find_frame_desc_stream_if(strmh->stream_if, format_id, frame_id);
}

/** @internal
 * @brief Find the descriptor for a specific frame configuration
 * @param devh UVC device
 * @param format_id Index of format class descriptor
 * @param frame_id Index of frame descriptor
 */
uvc_frame_desc_t *uvc_find_frame_desc(uvc_device_handle_t *devh,
		uint16_t format_id, uint16_t frame_id) {

	uvc_streaming_interface_t *stream_if;
	uvc_frame_desc_t *frame;

	DL_FOREACH(devh->info->stream_ifs, stream_if)
	{
		frame = _uvc_find_frame_desc_stream_if(stream_if, format_id, frame_id);
		if (frame)
			return frame;
	}

	return NULL;
}

static void _uvc_print_streaming_interface_one(uvc_streaming_interface_t *stream_if) {
//	struct uvc_device_info *parent;
//	struct uvc_streaming_interface *prev, *next;
	MARK("bInterfaceNumber:%d", stream_if->bInterfaceNumber);
	uvc_print_format_desc_one(stream_if->format_descs, NULL);
	MARK("bEndpointAddress:%d", stream_if->bEndpointAddress);
	MARK("bTerminalLink:%d", stream_if->bTerminalLink);
}

static uvc_error_t _prepare_stream_ctrl(uvc_device_handle_t *devh, uvc_stream_ctrl_t *ctrl) {
	// XXX some camera may need to call uvc_query_stream_ctrl with UVC_GET_CUR/UVC_GET_MAX/UVC_GET_MIN
	// before negotiation otherwise stream stall. added by saki
	uvc_error_t result = uvc_query_stream_ctrl(devh, ctrl, 1, UVC_GET_CUR);	// probe query
	if (LIKELY(!result)) {
		result = uvc_query_stream_ctrl(devh, ctrl, 1, UVC_GET_MIN);			// probe query
		if (LIKELY(!result)) {
			result = uvc_query_stream_ctrl(devh, ctrl, 1, UVC_GET_MAX);		// probe query
			if (UNLIKELY(result))
				LOGE("uvc_query_stream_ctrl:UVC_GET_MAX:err=%d", result);	// XXX 最大値の方を後で取得しないとだめ
		} else {
			LOGE("uvc_query_stream_ctrl:UVC_GET_MIN:err=%d", result);
		}
	} else {
		LOGE("uvc_query_stream_ctrl:UVC_GET_CUR:err=%d", result);
	}
#if 0
	if (UNLIKELY(result)) {
		enum uvc_error_code_control error_code;
		uvc_get_error_code(devh, &error_code, UVC_GET_CUR);
		LOGE("uvc_query_stream_ctrl:ret=%d,err_code=%d", result, error_code);
		uvc_print_format_desc(devh->info->stream_ifs->format_descs, NULL);
	}
#endif
	return result;
}

static uvc_error_t _uvc_get_stream_ctrl_format(uvc_device_handle_t *devh,
	uvc_streaming_interface_t *stream_if, uvc_stream_ctrl_t *ctrl, uvc_format_desc_t *format,
	const int width, const int height,
	const int min_fps, const int max_fps) {

	ENTER();

	int i;
	uvc_frame_desc_t *frame;

	ctrl->bInterfaceNumber = stream_if->bInterfaceNumber;
	uvc_error_t result = uvc_claim_if(devh, ctrl->bInterfaceNumber);
	if (UNLIKELY(result)) {
		LOGE("uvc_claim_if:err=%d", result);
		goto fail;
	}
	for (i = 0; i < 2; i++) {
		result = _prepare_stream_ctrl(devh, ctrl);
	}
	if (UNLIKELY(result)) {
		LOGE("_prepare_stream_ctrl:err=%d", result);
		goto fail;
	}
#if 0
	// XXX add check ctrl values
	uint64_t bmaControl = stream_if->bmaControls[format->bFormatIndex - 1];
	if (bmaControl & 0x001) {	// wKeyFrameRate
		if (UNLIKELY(!ctrl->wKeyFrameRate)) {
			LOGE("wKeyFrameRate should be set");
			RETURN(UVC_ERROR_INVALID_MODE, uvc_error_t);
		}
	}
	if (bmaControl & 0x002) {	// wPFrameRate
		if (UNLIKELY(!ctrl->wPFrameRate)) {
			LOGE("wPFrameRate should be set");
			RETURN(UVC_ERROR_INVALID_MODE, uvc_error_t);
		}
	}
	if (bmaControl & 0x004) {	// wCompQuality
		if (UNLIKELY(!ctrl->wCompQuality)) {
			LOGE("wCompQuality should be set");
			RETURN(UVC_ERROR_INVALID_MODE, uvc_error_t);
		}
	}
	if (bmaControl & 0x008) {	// wCompWindowSize
		if (UNLIKELY(!ctrl->wCompWindowSize)) {
			LOGE("wCompWindowSize should be set");
			RETURN(UVC_ERROR_INVALID_MODE, uvc_error_t);
		}
	}
#endif
	DL_FOREACH(format->frame_descs, frame)
	{
		if (frame->wWidth != width || frame->wHeight != height)
			continue;

		uint32_t *interval;

		if (frame->intervals) {
			for (interval = frame->intervals; *interval; ++interval) {
				if (UNLIKELY(!(*interval))) continue;
				uint32_t it = 10000000 / *interval;
				LOGV("it:%d", it);
				if ((it >= (uint32_t) min_fps) && (it <= (uint32_t) max_fps)) {
					ctrl->bmHint = (1 << 0); /* don't negotiate interval */
					ctrl->bFormatIndex = format->bFormatIndex;
					ctrl->bFrameIndex = frame->bFrameIndex;
					ctrl->dwFrameInterval = *interval;

					goto found;
				}
			}
		} else {
			int32_t fps;
			for (fps = max_fps; fps >= min_fps; fps--) {
				if (UNLIKELY(!fps)) continue;
				uint32_t interval_100ns = 10000000 / fps;
				uint32_t interval_offset = interval_100ns - frame->dwMinFrameInterval;
				LOGV("fps:%d", fps);
				if (interval_100ns >= frame->dwMinFrameInterval
					&& interval_100ns <= frame->dwMaxFrameInterval
					&& !(interval_offset
						&& (interval_offset % frame->dwFrameIntervalStep) ) ) {
					ctrl->bmHint = (1 << 0); /* don't negotiate interval */
					ctrl->bFormatIndex = format->bFormatIndex;
					ctrl->bFrameIndex = frame->bFrameIndex;
					ctrl->dwFrameInterval = interval_100ns;

					goto found;
				}
			}
		}
	}
	result = UVC_ERROR_INVALID_MODE;
fail:
	uvc_release_if(devh, ctrl->bInterfaceNumber);
	RETURN(result, uvc_error_t);

found:
	RETURN(UVC_SUCCESS, uvc_error_t);
}

/** Get a negotiated streaming control block for some common parameters.
 * @ingroup streaming
 *
 * @param[in] devh Device handle
 * @param[in,out] ctrl Control block
 * @param[in] cf Type of streaming format
 * @param[in] width Desired frame width
 * @param[in] height Desired frame height
 * @param[in] fps Frame rate, frames per second
 */
uvc_error_t uvc_get_stream_ctrl_format_size(uvc_device_handle_t *devh,
		uvc_stream_ctrl_t *ctrl, enum uvc_frame_format cf, int width, int height, int fps) {

	return uvc_get_stream_ctrl_format_size_fps(devh, ctrl, cf, width, height, fps, fps);
}

/** Get a negotiated streaming control block for some common parameters.
 * @ingroup streaming
 *
 * @param[in] devh Device handle
 * @param[in,out] ctrl Control block
 * @param[in] cf Type of streaming format
 * @param[in] width Desired frame width
 * @param[in] height Desired frame height
 * @param[in] min_fps Frame rate, minimum frames per second, this value is included
 * @param[in] max_fps Frame rate, maximum frames per second, this value is included
 */
uvc_error_t uvc_get_stream_ctrl_format_size_fps(uvc_device_handle_t *devh,
		uvc_stream_ctrl_t *ctrl, enum uvc_frame_format cf, int width,
		int height, int min_fps, int max_fps) {

	ENTER();

	uvc_streaming_interface_t *stream_if;
	uvc_error_t result;

	memset(ctrl, 0, sizeof(*ctrl));	// XXX add
	/* find a matching frame descriptor and interval */
	uvc_format_desc_t *format;
	DL_FOREACH(devh->info->stream_ifs, stream_if)
	{
		DL_FOREACH(stream_if->format_descs, format)
		{
			if (!_uvc_frame_format_matches_guid(cf, format->guidFormat))
				continue;

			result = _uvc_get_stream_ctrl_format(devh, stream_if, ctrl, format, width, height, min_fps, max_fps);
			if (!result) {	// UVC_SUCCESS
				goto found;
			}
		}
	}

	RETURN(UVC_ERROR_INVALID_MODE, uvc_error_t);

found:
	RETURN(uvc_probe_stream_ctrl(devh, ctrl), uvc_error_t);
}

/** @internal
 * Negotiate streaming parameters with the device
 *
 * @param[in] devh UVC device
 * @param[in,out] ctrl Control block
 */
uvc_error_t uvc_probe_stream_ctrl(uvc_device_handle_t *devh,
		uvc_stream_ctrl_t *ctrl) {
	uvc_error_t err;

	err = uvc_claim_if(devh, ctrl->bInterfaceNumber);
	if (UNLIKELY(err)) {
		LOGE("uvc_claim_if:err=%d", err);
		return err;
	}

	err = uvc_query_stream_ctrl(devh, ctrl, 1, UVC_SET_CUR);	// probe query
	if (UNLIKELY(err)) {
		LOGE("uvc_query_stream_ctrl(UVC_SET_CUR):err=%d", err);
		return err;
	}

	err = uvc_query_stream_ctrl(devh, ctrl, 1, UVC_GET_CUR);	// probe query ここでエラーが返ってくる
	if (UNLIKELY(err)) {
		LOGE("uvc_query_stream_ctrl(UVC_GET_CUR):err=%d", err);
		return err;
	}

	return UVC_SUCCESS;
}

/** @internal
 * @brief Swap the working buffer with the presented buffer and notify consumers
 */
static void _uvc_swap_buffers(uvc_stream_handle_t *strmh) {
	uint8_t *tmp_buf;

	pthread_mutex_lock(&strmh->cb_mutex);
	{
		/* swap the buffers */
		tmp_buf = strmh->holdbuf;
		strmh->hold_bfh_err = strmh->bfh_err;	// XXX
		strmh->hold_bytes = strmh->got_bytes;
		strmh->holdbuf = strmh->outbuf;
		strmh->outbuf = tmp_buf;
		strmh->hold_last_scr = strmh->last_scr;
		strmh->hold_pts = strmh->pts;
		strmh->hold_seq = strmh->seq;

		pthread_cond_broadcast(&strmh->cb_cond);
	}
	pthread_mutex_unlock(&strmh->cb_mutex);

	strmh->seq++;
	strmh->got_bytes = 0;
	strmh->last_scr = 0;
	strmh->pts = 0;
	strmh->bfh_err = 0;	// XXX
}

static void _uvc_delete_transfer(struct libusb_transfer *transfer) {
	ENTER();

//	MARK("");
	uvc_stream_handle_t *strmh = transfer->user_data;
	if (UNLIKELY(!strmh)) EXIT();		// XXX
	int i;

	pthread_mutex_lock(&strmh->cb_mutex);	// XXX crash while calling uvc_stop_streaming
	{
		// Mark transfer as deleted.
		for (i = 0; i < LIBUVC_NUM_TRANSFER_BUFS; i++) {
			if (strmh->transfers[i] == transfer) {
				libusb_cancel_transfer(strmh->transfers[i]);	// XXX 20141112追加
				UVC_DEBUG("Freeing transfer %d (%p)", i, transfer);
				free(transfer->buffer);
				// libusb_free_transfer(transfer);
				strmh->transfers[i] = NULL;
				break;
			}
		}
		if (UNLIKELY(i == LIBUVC_NUM_TRANSFER_BUFS)) {
			UVC_DEBUG("transfer %p not found; not freeing!", transfer);
		}

		pthread_cond_broadcast(&strmh->cb_cond);
	}
	pthread_mutex_unlock(&strmh->cb_mutex);
	EXIT();
}

#define USE_EOF

/** @internal
 * @brief Process a payload transfer
 * 
 * Processes stream, places frames into buffer, signals listeners
 * (such as user callback thread and any polling thread) on new frame
 *
 * @param payload Contents of the payload transfer, either a packet (isochronous) or a full
 * transfer (bulk mode)
 * @param payload_len Length of the payload transfer
 */
static void _uvc_process_payload(uvc_stream_handle_t *strmh, const uint8_t *payload, size_t const payload_len) {
	size_t header_len;
	uint8_t header_info;
	size_t data_len;
	struct libusb_iso_packet_descriptor *pkt;
	uvc_vc_error_code_control_t vc_error_code;
	uvc_vs_error_code_control_t vs_error_code;

	// magic numbers for identifying header packets from some iSight cameras
	static const uint8_t isight_tag[] = {
		0x11, 0x22, 0x33, 0x44,
		0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xfa, 0xce
	};

	// ignore empty payload transfers
	if (UNLIKELY(!payload || !payload_len || !strmh->outbuf))
		return;

	/* Certain iSight cameras have strange behavior: They send header
	 * information in a packet with no image data, and then the following
  	 * packets have only image data, with no more headers until the next frame.
	 *
	 * The iSight header: len(1), flags(1 or 2), 0x11223344(4),
	 * 0xdeadbeefdeadface(8), ??(16)
	*/

	if (UNLIKELY(strmh->devh->is_isight &&
		((payload_len < 14) || memcmp(isight_tag, payload + 2, sizeof(isight_tag)) ) &&
		((payload_len < 15) || memcmp(isight_tag, payload + 3, sizeof(isight_tag)) ) )) {
		// The payload transfer doesn't have any iSight magic, so it's all image data
		header_len = 0;
		data_len = payload_len;
	} else {
		header_len = payload[0];

		if (UNLIKELY(header_len > payload_len)) {
			strmh->bfh_err |= UVC_STREAM_ERR;
			UVC_DEBUG("bogus packet: actual_len=%zd, header_len=%zd\n", payload_len, header_len);
			return;
		}

		if (UNLIKELY(strmh->devh->is_isight))
			data_len = 0;
		else
			data_len = payload_len - header_len;
	}

	if (UNLIKELY(header_len < 2)) {
		header_info = 0;
	} else {
		//  @todo we should be checking the end-of-header bit
		size_t variable_offset = 2;

		header_info = payload[1];

		if (UNLIKELY(header_info & UVC_STREAM_ERR)) {
//			strmh->bfh_err |= UVC_STREAM_ERR;
			UVC_DEBUG("bad packet: error bit set");
			libusb_clear_halt(strmh->devh->usb_devh, strmh->stream_if->bEndpointAddress);
//			uvc_vc_get_error_code(strmh->devh, &vc_error_code, UVC_GET_CUR);
			uvc_vs_get_error_code(strmh->devh, &vs_error_code, UVC_GET_CUR);
//			return;
		}

		if ((strmh->fid != (header_info & UVC_STREAM_FID)) && strmh->got_bytes) {
			/* The frame ID bit was flipped, but we have image data sitting
				around from prior transfers. This means the camera didn't send
				an EOF for the last transfer of the previous frame. */
			_uvc_swap_buffers(strmh);
		}

		strmh->fid = header_info & UVC_STREAM_FID;

		if (header_info & UVC_STREAM_PTS) {
			// XXX saki some camera may send broken packet or failed to receive all data
			if (LIKELY(variable_offset + 4 <= header_len)) {
				strmh->pts = DW_TO_INT(payload + variable_offset);
				variable_offset += 4;
			} else {
				MARK("bogus packet: header info has UVC_STREAM_PTS, but no data");
				strmh->pts = 0;
			}
		}

		if (header_info & UVC_STREAM_SCR) {
			// @todo read the SOF token counter
			// XXX saki some camera may send broken packet or failed to receive all data
			if (LIKELY(variable_offset + 4 <= header_len)) {
				strmh->last_scr = DW_TO_INT(payload + variable_offset);
				variable_offset += 4;
			} else {
				MARK("bogus packet: header info has UVC_STREAM_SCR, but no data");
				strmh->last_scr = 0;
			}
		}
	}

	if (LIKELY(data_len > 0)) {
		if (LIKELY(strmh->got_bytes + data_len < strmh->size_buf)) {
			memcpy(strmh->outbuf + strmh->got_bytes, payload + header_len, data_len);
			strmh->got_bytes += data_len;
		} else {
			strmh->bfh_err |= UVC_STREAM_ERR;
		}

		if (header_info & UVC_STREAM_EOF/*(1 << 1)*/) {
			// The EOF bit is set, so publish the complete frame
			_uvc_swap_buffers(strmh);
		}
	}
}

#if 0
static inline void _uvc_process_payload_iso(uvc_stream_handle_t *strmh, struct libusb_transfer *transfer) {
	/* This is an isochronous mode transfer, so each packet has a payload transfer */
	int packet_id;
	for (packet_id = 0; packet_id < transfer->num_iso_packets; packet_id++) {
		struct libusb_iso_packet_descriptor *pkt = transfer->iso_packet_desc + packet_id;

		if UNLIKELY(pkt->status) {
//			UVC_DEBUG("bad packet:status=%d,actual_length=%d", pkt->status, pkt->actual_length);
			MARK("bad packet:status=%d,actual_length=%d", pkt->status, pkt->actual_length);
			continue;
		}
		if UNLIKELY(!pkt->actual_length) {
			MARK("zero packet (transfer):");
			continue;
		}
		// libusb_get_iso_packet_buffer_simple will return NULL
		uint8_t *pktbuf = libusb_get_iso_packet_buffer_simple(transfer, packet_id);
		_uvc_process_payload(strmh, pktbuf, pkt->actual_length);
	}
}
#else
static inline void _uvc_process_payload_iso(uvc_stream_handle_t *strmh, struct libusb_transfer *transfer) {
	/* per packet */
	uint8_t *pktbuf;
	uint8_t check_header;
	size_t header_len;
	uint8_t header_info;
	struct libusb_iso_packet_descriptor *pkt;

	/* magic numbers for identifying header packets from some iSight cameras */
	static const uint8_t isight_tag[] = {
		0x11, 0x22, 0x33, 0x44, 0xde, 0xad,
		0xbe, 0xef, 0xde, 0xad, 0xfa, 0xce };
	int packet_id;
	uvc_vc_error_code_control_t vc_error_code;
	uvc_vs_error_code_control_t vs_error_code;

	for (packet_id = 0; packet_id < transfer->num_iso_packets; ++packet_id) {
		check_header = 1;

		pkt = transfer->iso_packet_desc + packet_id;

		if (UNLIKELY(pkt->status != 0)) {
			MARK("bad packet:status=%d,actual_length=%d", pkt->status, pkt->actual_length);
			strmh->bfh_err |= UVC_STREAM_ERR;
			libusb_clear_halt(strmh->devh->usb_devh, strmh->stream_if->bEndpointAddress);
//			uvc_vc_get_error_code(strmh->devh, &vc_error_code, UVC_GET_CUR);
//			uvc_vs_get_error_code(strmh->devh, &vs_error_code, UVC_GET_CUR);
			continue;
		}

		if (UNLIKELY(!pkt->actual_length)) {	// why transfered byte is zero...
//			MARK("zero packet (transfer):");
//			strmh->bfh_err |= UVC_STREAM_ERR;	// don't set this flag here
			continue;
		}
		// XXX accessing to pktbuf could lead to crash on the original implementation
		// because the substances of pktbuf will be deleted in uvc_stream_stop.
		pktbuf = libusb_get_iso_packet_buffer_simple(transfer, packet_id);
		if (LIKELY(pktbuf)) {	// XXX add null check because libusb_get_iso_packet_buffer_simple could return null
//			assert(pktbuf < transfer->buffer + transfer->length - 1);	// XXX
#ifdef __ANDROID__
			// XXX optimaization because this flag never become true on Android devices
			if (UNLIKELY(strmh->devh->is_isight))
#else
			if (strmh->devh->is_isight)
#endif
			{
				if (pkt->actual_length < 30
					|| (memcmp(isight_tag, pktbuf + 2, sizeof(isight_tag))
						&& memcmp(isight_tag, pktbuf + 3, sizeof(isight_tag)))) {
					check_header = 0;
					header_len = 0;
				} else {
					header_len = pktbuf[0];
				}
			} else {
				header_len = pktbuf[0];	// Header length field of Stream Header
			}

			if (LIKELY(check_header)) {
				header_info = pktbuf[1];
				if (UNLIKELY(header_info & UVC_STREAM_ERR)) {
//					strmh->bfh_err |= UVC_STREAM_ERR;
					MARK("bad packet:status=0x%2x", header_info);
					libusb_clear_halt(strmh->devh->usb_devh, strmh->stream_if->bEndpointAddress);
//					uvc_vc_get_error_code(strmh->devh, &vc_error_code, UVC_GET_CUR);
					uvc_vs_get_error_code(strmh->devh, &vs_error_code, UVC_GET_CUR);
					continue;
				}
#ifdef USE_EOF
				if ((strmh->fid != (header_info & UVC_STREAM_FID)) && strmh->got_bytes) {	// got_bytesを取ると殆ど画面更新されない
				/* The frame ID bit was flipped, but we have image data sitting
	             around from prior transfers. This means the camera didn't send
    		     an EOF for the last transfer of the previous frame or some frames losted. */
					_uvc_swap_buffers(strmh);
				}
				strmh->fid = header_info & UVC_STREAM_FID;
#else
				if (strmh->fid != (header_info & UVC_STREAM_FID)) {	// when FID is toggled
					_uvc_swap_buffers(strmh);
					strmh->fid = header_info & UVC_STREAM_FID;
				}
#endif
				if (header_info & UVC_STREAM_PTS) {
					// XXX saki some camera may send broken packet or failed to receive all data
					if (LIKELY(header_len >= 6)) {
						strmh->pts = DW_TO_INT(pktbuf + 2);
					} else {
						MARK("bogus packet: header info has UVC_STREAM_PTS, but no data");
						strmh->pts = 0;
					}
				}

				if (header_info & UVC_STREAM_SCR) {
					// XXX saki some camera may send broken packet or failed to receive all data
					if (LIKELY(header_len >= 10)) {
						strmh->last_scr = DW_TO_INT(pktbuf + 6);
					} else {
						MARK("bogus packet: header info has UVC_STREAM_SCR, but no data");
						strmh->last_scr = 0;
					}
				}

#ifdef __ANDROID__	// XXX optimaization because this flag never become true on Android devices
				if (UNLIKELY(strmh->devh->is_isight))
					continue; // don't look for data after an iSight header
#else
				if (strmh->devh->is_isight) {
					MARK("is_isight");
					continue; // don't look for data after an iSight header
				}
#endif
			} // if LIKELY(check_header)

			if (UNLIKELY(pkt->actual_length < header_len)) {
				/* Bogus packet received */
				strmh->bfh_err |= UVC_STREAM_ERR;
				MARK("bogus packet: actual_len=%d, header_len=%zd", pkt->actual_length, header_len);
				continue;
			}

			// XXX original implementation could lead to trouble because unsigned values
			// and there calculated value never become minus.
			// therefor changed to "if (pkt->actual_length > header_len)"
			// from "if (pkt->actual_length - header_len > 0)"
			if (LIKELY(pkt->actual_length > header_len)) {
				const size_t odd_bytes = pkt->actual_length - header_len;
				assert(strmh->got_bytes + odd_bytes < strmh->size_buf);
				assert(strmh->outbuf);
				assert(pktbuf);
				memcpy(strmh->outbuf + strmh->got_bytes, pktbuf + header_len, odd_bytes);
				strmh->got_bytes += odd_bytes;
			}
#ifdef USE_EOF
			if ((pktbuf[1] & UVC_STREAM_EOF) && strmh->got_bytes != 0) {
				/* The EOF bit is set, so publish the complete frame */
				_uvc_swap_buffers(strmh);
			}
#endif
		} else {	// if (LIKELY(pktbuf))
			strmh->bfh_err |= UVC_STREAM_ERR;
			MARK("libusb_get_iso_packet_buffer_simple returned null");
			continue;
		}
	}	// for
}
#endif

/** @internal
 * @brief Isochronous transfer callback
 * 
 * Processes stream, places frames into buffer, signals listeners
 * (such as user callback thread and any polling thread) on new frame
 *
 * @param transfer Active transfer
 */
static void _uvc_stream_callback(struct libusb_transfer *transfer) {
	if UNLIKELY(!transfer) return;

	uvc_stream_handle_t *strmh = transfer->user_data;
	if UNLIKELY(!strmh) return;

	int resubmit = 1;

#ifndef NDEBUG
	static int cnt = 0;
	if UNLIKELY((++cnt % 1000) == 0)
		MARK("cnt=%d", cnt);
#endif
	switch (transfer->status) {
	case LIBUSB_TRANSFER_COMPLETED:
		if (!transfer->num_iso_packets) {
			/* This is a bulk mode transfer, so it just has one payload transfer */
			_uvc_process_payload(strmh, transfer->buffer, transfer->actual_length);
		} else {
			/* This is an isochronous mode transfer, so each packet has a payload transfer */
			_uvc_process_payload_iso(strmh, transfer);
		}
	    break;
	case LIBUSB_TRANSFER_NO_DEVICE:
		strmh->running = 0;	// this needs for unexpected disconnect of cable otherwise hangup
		// pass through to following lines
	case LIBUSB_TRANSFER_CANCELLED:
	case LIBUSB_TRANSFER_ERROR:
		UVC_DEBUG("not retrying transfer, status = %d", transfer->status);
//		MARK("not retrying transfer, status = %d", transfer->status);
//		_uvc_delete_transfer(transfer);
		resubmit = 0;
		break;
	case LIBUSB_TRANSFER_TIMED_OUT:
	case LIBUSB_TRANSFER_STALL:
	case LIBUSB_TRANSFER_OVERFLOW:
		UVC_DEBUG("retrying transfer, status = %d", transfer->status);
//		MARK("retrying transfer, status = %d", transfer->status);
		break;
	}

	if (LIKELY(strmh->running && resubmit)) {
		libusb_submit_transfer(transfer);
	} else {
		// XXX delete non-reusing transfer
		// real implementation of deleting transfer moves to _uvc_delete_transfer
		_uvc_delete_transfer(transfer);
	}
}

#if 0
/** @internal
 * @brief Isochronous transfer callback
 * 
 * Processes stream, places frames into buffer, signals listeners
 * (such as user callback thread and any polling thread) on new frame
 *
 * @param transfer Active transfer
 */
static void _uvc_iso_callback(struct libusb_transfer *transfer) {
	uvc_stream_handle_t *strmh;
	int packet_id;

	/* per packet */
	uint8_t *pktbuf;
	uint8_t check_header;
	size_t header_len;	// XXX unsigned int header_len
	uint8_t header_info;
	struct libusb_iso_packet_descriptor *pkt;

	/* magic numbers for identifying header packets from some iSight cameras */
	static const uint8_t isight_tag[] = {
		0x11, 0x22, 0x33, 0x44, 0xde, 0xad,
		0xbe, 0xef, 0xde, 0xad, 0xfa, 0xce };

	strmh = transfer->user_data;
#ifndef NDEBUG
	static int cnt = 0;
	if ((++cnt % 1000) == 0)
		MARK("cnt=%d", cnt);
#endif
	switch (transfer->status) {
	case LIBUSB_TRANSFER_COMPLETED:
		if (UNLIKELY(!transfer->num_iso_packets))
			MARK("num_iso_packets is zero");
		for (packet_id = 0; packet_id < transfer->num_iso_packets; ++packet_id) {
			check_header = 1;

			pkt = transfer->iso_packet_desc + packet_id;

			if (UNLIKELY(pkt->status != 0)) {
				MARK("bad packet:status=%d,actual_length=%d", pkt->status, pkt->actual_length);
				strmh->bfh_err |= UVC_STREAM_ERR;
				continue;
			}

			if (UNLIKELY(!pkt->actual_length)) {	// why transfered byte is zero...
//				MARK("zero packet (transfer):");
//				strmh->bfh_err |= UVC_STREAM_ERR;	// don't set this flag here
				continue;
			}
			// XXX accessing to pktbuf could lead to crash on the original implementation
			// because the substances of pktbuf will be deleted in uvc_stream_stop.
			pktbuf = libusb_get_iso_packet_buffer_simple(transfer, packet_id);
			if (LIKELY(pktbuf)) {	// XXX add null check because libusb_get_iso_packet_buffer_simple could return null
//				assert(pktbuf < transfer->buffer + transfer->length - 1);	// XXX
#ifdef __ANDROID__
				// XXX optimaization because this flag never become true on Android devices
				if (UNLIKELY(strmh->devh->is_isight))
#else
				if (strmh->devh->is_isight)
#endif
				{
					if (pkt->actual_length < 30
						|| (memcmp(isight_tag, pktbuf + 2, sizeof(isight_tag))
							&& memcmp(isight_tag, pktbuf + 3, sizeof(isight_tag)))) {
						check_header = 0;
						header_len = 0;
					} else {
						header_len = pktbuf[0];
					}
				} else {
					header_len = pktbuf[0];	// Header length field of Stream Header
				}

				if (LIKELY(check_header)) {
					header_info = pktbuf[1];
					if (UNLIKELY(header_info & UVC_STREAM_ERR)) {
						strmh->bfh_err |= UVC_STREAM_ERR;
						MARK("bad packet");
//						libusb_clear_halt(strmh->devh->usb_devh, strmh->stream_if->bEndpointAddress);
						uvc_vc_get_error_code(strmh->devh, &vc_error_code, UVC_GET_CUR);
						uvc_vs_get_error_code(strmh->devh, &vs_error_code, UVC_GET_CUR);
						continue;
					}
#ifdef USE_EOF
					if ((strmh->fid != (header_info & UVC_STREAM_FID)) && strmh->got_bytes) {	// got_bytesを取ると殆ど画面更新されない
					/* The frame ID bit was flipped, but we have image data sitting
		             around from prior transfers. This means the camera didn't send
        		     an EOF for the last transfer of the previous frame or some frames losted. */
						_uvc_swap_buffers(strmh);
					}
					strmh->fid = header_info & UVC_STREAM_FID;
#else
					if (strmh->fid != (header_info & UVC_STREAM_FID)) {	// when FID is toggled
						_uvc_swap_buffers(strmh);
						strmh->fid = header_info & UVC_STREAM_FID;
					}
#endif
					if (header_info & UVC_STREAM_PTS) {
						// XXX saki some camera may send broken packet or failed to receive all data
						if (LIKELY(header_len >= 6)) {
							strmh->pts = DW_TO_INT(pktbuf + 2);
						} else {
							MARK("bogus packet: header info has UVC_STREAM_PTS, but no data");
							strmh->pts = 0;
						}
					}

					if (header_info & UVC_STREAM_SCR) {
						// XXX saki some camera may send broken packet or failed to receive all data
						if (LIKELY(header_len >= 10)) {
							strmh->last_scr = DW_TO_INT(pktbuf + 6);
						} else {
							MARK("bogus packet: header info has UVC_STREAM_SCR, but no data");
							strmh->last_scr = 0;
						}
					}

#ifdef __ANDROID__	// XXX optimaization because this flag never become true on Android devices
					if (UNLIKELY(strmh->devh->is_isight))
						continue; // don't look for data after an iSight header
#else
					if (strmh->devh->is_isight) {
						MARK("is_isight");
						continue; // don't look for data after an iSight header
					}
#endif
				} // if LIKELY(check_header)

				if (UNLIKELY(pkt->actual_length < header_len)) {
					/* Bogus packet received */
					strmh->bfh_err |= UVC_STREAM_ERR;
					MARK("bogus packet: actual_len=%d, header_len=%zd", pkt->actual_length, header_len);
					continue;
				}

				// XXX original implementation could lead to trouble because unsigned values
				// and there calculated value never become minus.
				// therefor changed to "if (pkt->actual_length > header_len)"
				// from "if (pkt->actual_length - header_len > 0)"
				if (LIKELY(pkt->actual_length > header_len)) {
					const size_t odd_bytes = pkt->actual_length - header_len;
					assert(strmh->got_bytes + odd_bytes < strmh->size_buf);
					assert(strmh->outbuf);
					assert(pktbuf);
					memcpy(strmh->outbuf + strmh->got_bytes, pktbuf + header_len, odd_bytes);
					strmh->got_bytes += odd_bytes;
				}
#ifdef USE_EOF
				if ((pktbuf[1] & STREAM_HEADER_BFH_EOF) && strmh->got_bytes != 0) {
					/* The EOF bit is set, so publish the complete frame */
					_uvc_swap_buffers(strmh);
				}
#endif
			} else {	// if (LIKELY(pktbuf))
				strmh->bfh_err |= UVC_STREAM_ERR;
				MARK("libusb_get_iso_packet_buffer_simple returned null");
				continue;
			}
		}	// for
		break;
	case LIBUSB_TRANSFER_NO_DEVICE:
		strmh->running = 0;	// this needs for unexpected disconnect of cable otherwise hangup
	case LIBUSB_TRANSFER_CANCELLED:
	case LIBUSB_TRANSFER_ERROR:
		UVC_DEBUG("not retrying transfer, status = %d", transfer->status);
//		MARK("not retrying transfer, status = %d", transfer->status);
		_uvc_delete_transfer(transfer);
		break;
	case LIBUSB_TRANSFER_TIMED_OUT:
	case LIBUSB_TRANSFER_STALL:
	case LIBUSB_TRANSFER_OVERFLOW:
		UVC_DEBUG("retrying transfer, status = %d", transfer->status);
//		MARK("retrying transfer, status = %d", transfer->status);
		break;
	}

	if (LIKELY(strmh->running)) {
		libusb_submit_transfer(transfer);
	} else {
		// XXX delete non-reusing transfer
		// real implementation of deleting transfer moves to _uvc_delete_transfer
		_uvc_delete_transfer(transfer);
	}
}
#endif

/** Begin streaming video from the camera into the callback function.
 * @ingroup streaming
 *
 * @param devh UVC device
 * @param ctrl Control block, processed using {uvc_probe_stream_ctrl} or
 *             {uvc_get_stream_ctrl_format_size}
 * @param cb   User callback function. See {uvc_frame_callback_t} for restrictions.
 * @param flags Stream setup flags, currently undefined. Set this to zero. The lower bit
 * is reserved for backward compatibility.
 */
uvc_error_t uvc_start_streaming(uvc_device_handle_t *devh,
		uvc_stream_ctrl_t *ctrl, uvc_frame_callback_t *cb, void *user_ptr,
		uint8_t flags) {
	return uvc_start_streaming_bandwidth(devh, ctrl, cb, user_ptr, 0, flags);
}

/** Begin streaming video from the camera into the callback function.
 * @ingroup streaming
 *
 * @param devh UVC device
 * @param ctrl Control block, processed using {uvc_probe_stream_ctrl} or
 *             {uvc_get_stream_ctrl_format_size}
 * @param cb   User callback function. See {uvc_frame_callback_t} for restrictions.
 * @param bandwidth_factor [0.0f, 1.0f]
 * @param flags Stream setup flags, currently undefined. Set this to zero. The lower bit
 * is reserved for backward compatibility.
 */
uvc_error_t uvc_start_streaming_bandwidth(uvc_device_handle_t *devh,
		uvc_stream_ctrl_t *ctrl, uvc_frame_callback_t *cb, void *user_ptr,
		float bandwidth_factor,
		uint8_t flags) {
	uvc_error_t ret;
	uvc_stream_handle_t *strmh;

	ret = uvc_stream_open_ctrl(devh, &strmh, ctrl);
	if (UNLIKELY(ret != UVC_SUCCESS))
		return ret;

	ret = uvc_stream_start_bandwidth(strmh, cb, user_ptr, bandwidth_factor, flags);
	if (UNLIKELY(ret != UVC_SUCCESS)) {
		uvc_stream_close(strmh);
		return ret;
	}

	return UVC_SUCCESS;
}

/** Begin streaming video from the camera into the callback function.
 * @ingroup streaming
 *
 * @deprecated The stream type (bulk vs. isochronous) will be determined by the
 * type of interface associated with the uvc_stream_ctrl_t parameter, regardless
 * of whether the caller requests isochronous streaming. Please switch to
 * uvc_start_streaming().
 *
 * @param devh UVC device
 * @param ctrl Control block, processed using {uvc_probe_stream_ctrl} or
 *             {uvc_get_stream_ctrl_format_size}
 * @param cb   User callback function. See {uvc_frame_callback_t} for restrictions.
 */
uvc_error_t uvc_start_iso_streaming(uvc_device_handle_t *devh,
		uvc_stream_ctrl_t *ctrl, uvc_frame_callback_t *cb, void *user_ptr) {
	return uvc_start_streaming_bandwidth(devh, ctrl, cb, user_ptr, 0.0f, 0);
}

static uvc_stream_handle_t *_uvc_get_stream_by_interface(
		uvc_device_handle_t *devh, int interface_idx) {
	uvc_stream_handle_t *strmh;

	DL_FOREACH(devh->streams, strmh)
	{
		if (strmh->stream_if->bInterfaceNumber == interface_idx)
			return strmh;
	}

	return NULL;
}

static uvc_streaming_interface_t *_uvc_get_stream_if(uvc_device_handle_t *devh,
		int interface_idx) {
	uvc_streaming_interface_t *stream_if;

	DL_FOREACH(devh->info->stream_ifs, stream_if)
	{
		if (stream_if->bInterfaceNumber == interface_idx)
			return stream_if;
	}

	return NULL;
}

/** Open a new video stream.
 * @ingroup streaming
 *
 * @param devh UVC device
 * @param ctrl Control block, processed using {uvc_probe_stream_ctrl} or
 *             {uvc_get_stream_ctrl_format_size}
 */
uvc_error_t uvc_stream_open_ctrl(uvc_device_handle_t *devh,
		uvc_stream_handle_t **strmhp, uvc_stream_ctrl_t *ctrl) {
	/* Chosen frame and format descriptors */
	uvc_stream_handle_t *strmh = NULL;
	uvc_streaming_interface_t *stream_if;
	uvc_error_t ret;

	UVC_ENTER();

	if (UNLIKELY(_uvc_get_stream_by_interface(devh, ctrl->bInterfaceNumber) != NULL)) {
		ret = UVC_ERROR_BUSY; /* Stream is already opened */
		goto fail;
	}

	stream_if = _uvc_get_stream_if(devh, ctrl->bInterfaceNumber);
	if (UNLIKELY(!stream_if)) {
		ret = UVC_ERROR_INVALID_PARAM;
		goto fail;
	}

	strmh = calloc(1, sizeof(*strmh));
	if (UNLIKELY(!strmh)) {
		ret = UVC_ERROR_NO_MEM;
		goto fail;
	}
	strmh->devh = devh;
	strmh->stream_if = stream_if;
	strmh->frame.library_owns_data = 1;

	ret = uvc_claim_if(strmh->devh, strmh->stream_if->bInterfaceNumber);
	if (UNLIKELY(ret != UVC_SUCCESS))
		goto fail;

	ret = uvc_stream_ctrl(strmh, ctrl);
	if (UNLIKELY(ret != UVC_SUCCESS))
		goto fail;

	// Set up the streaming status and data space
	strmh->running = 0;
	/** @todo take only what we need */
	strmh->outbuf = malloc(LIBUVC_XFER_BUF_SIZE);
	strmh->holdbuf = malloc(LIBUVC_XFER_BUF_SIZE);
	strmh->size_buf = LIBUVC_XFER_BUF_SIZE;	// xxx for boundary check

	pthread_mutex_init(&strmh->cb_mutex, NULL);
	pthread_cond_init(&strmh->cb_cond, NULL);

	DL_APPEND(devh->streams, strmh);

	*strmhp = strmh;

	UVC_EXIT(0);
	return UVC_SUCCESS;

fail:
	if (strmh)
		free(strmh);
	UVC_EXIT(ret);
	return ret;
}

/** Begin streaming video from the stream into the callback function.
 * @ingroup streaming
 *
 * @param strmh UVC stream
 * @param cb   User callback function. See {uvc_frame_callback_t} for restrictions.
 * @param flags Stream setup flags, currently undefined. Set this to zero. The lower bit
 * is reserved for backward compatibility.
 */
uvc_error_t uvc_stream_start(uvc_stream_handle_t *strmh,
		uvc_frame_callback_t *cb, void *user_ptr, uint8_t flags) {
	return uvc_stream_start_bandwidth(strmh, cb, user_ptr, 0, flags);
}

/** Begin streaming video from the stream into the callback function.
 * @ingroup streaming
 *
 * @param strmh UVC stream
 * @param cb   User callback function. See {uvc_frame_callback_t} for restrictions.
 * @param bandwidth_factor [0.0f, 1.0f]
 * @param flags Stream setup flags, currently undefined. Set this to zero. The lower bit
 * is reserved for backward compatibility.
 */
uvc_error_t uvc_stream_start_bandwidth(uvc_stream_handle_t *strmh,
		uvc_frame_callback_t *cb, void *user_ptr, float bandwidth_factor, uint8_t flags) {
	/* USB interface we'll be using */
	const struct libusb_interface *interface;
	int interface_id;
	char isochronous;
	uvc_frame_desc_t *frame_desc;
	uvc_format_desc_t *format_desc;
	uvc_stream_ctrl_t *ctrl;
	uvc_error_t ret;
	/* Total amount of data per transfer */
	size_t total_transfer_size;
	struct libusb_transfer *transfer;
	int transfer_id;

	ctrl = &strmh->cur_ctrl;

	UVC_ENTER();

	if (UNLIKELY(strmh->running)) {
		UVC_EXIT(UVC_ERROR_BUSY);
		return UVC_ERROR_BUSY;
	}

	strmh->running = 1;
	strmh->seq = 0;
	strmh->fid = 0;
	strmh->pts = 0;
	strmh->last_scr = 0;
	strmh->bfh_err = 0;	// XXX

	frame_desc = uvc_find_frame_desc_stream(strmh, ctrl->bFormatIndex, ctrl->bFrameIndex);
	if (UNLIKELY(!frame_desc)) {
		ret = UVC_ERROR_INVALID_PARAM;
		LOGE("UVC_ERROR_INVALID_PARAM");
		goto fail;
	}
	format_desc = frame_desc->parent;

	strmh->frame_format = uvc_frame_format_for_guid(format_desc->guidFormat);
	if (UNLIKELY(strmh->frame_format == UVC_FRAME_FORMAT_UNKNOWN)) {
		ret = UVC_ERROR_NOT_SUPPORTED;
		LOGE("unlnown frame format");
		goto fail;
	}
	const uint32_t dwMaxVideoFrameSize = ctrl->dwMaxVideoFrameSize <= frame_desc->dwMaxVideoFrameBufferSize
		? ctrl->dwMaxVideoFrameSize : frame_desc->dwMaxVideoFrameBufferSize;

	// Get the interface that provides the chosen format and frame configuration
	interface_id = strmh->stream_if->bInterfaceNumber;
	interface = &strmh->devh->info->config->interface[interface_id];

	/* A VS interface uses isochronous transfers if it has multiple altsettings.
	 * (UVC 1.5: 2.4.3. VideoStreaming Interface, on page 19) */
	isochronous = interface->num_altsetting > 1;

	if (isochronous) {
		MARK("isochronous transfer mode:num_altsetting=%d", interface->num_altsetting);
		/* For isochronous streaming, we choose an appropriate altsetting for the endpoint
		 * and set up several transfers */
		const struct libusb_interface_descriptor *altsetting;
		const struct libusb_endpoint_descriptor *endpoint;
		/* The greatest number of bytes that the device might provide, per packet, in this
		 * configuration */
		size_t config_bytes_per_packet;
		/* Number of packets per transfer */
		size_t packets_per_transfer;
		/* Total amount of data per transfer */
		size_t total_transfer_size;
		/* Size of packet transferable from the chosen endpoint */
		size_t endpoint_bytes_per_packet;
		/* Index of the altsetting */
		int alt_idx, ep_idx;

		struct libusb_transfer *transfer;
		int transfer_id;
		
		if ((bandwidth_factor > 0) && (bandwidth_factor < 1.0f)) {
			config_bytes_per_packet = (size_t)(strmh->cur_ctrl.dwMaxPayloadTransferSize * bandwidth_factor);
			if (!config_bytes_per_packet) {
				config_bytes_per_packet = strmh->cur_ctrl.dwMaxPayloadTransferSize;
			}
		} else {
			config_bytes_per_packet = strmh->cur_ctrl.dwMaxPayloadTransferSize;
		}
//#if !defined(__LP64__)
//		LOGI("config_bytes_per_packet=%d", config_bytes_per_packet);
//#else
//		LOGI("config_bytes_per_packet=%ld", config_bytes_per_packet);
//#endif
		if (UNLIKELY(!config_bytes_per_packet)) {	// XXX added to privent zero divided exception at the following code
			ret = UVC_ERROR_IO;
			LOGE("config_bytes_per_packet is zero");
			goto fail;
		}

		/* Go through the altsettings and find one whose packets are at least
		 * as big as our format's maximum per-packet usage. Assume that the
		 * packet sizes are increasing. */
		const int num_alt = interface->num_altsetting - 1;
		for (alt_idx = 0; alt_idx <= num_alt ; alt_idx++) {
			altsetting = interface->altsetting + alt_idx;
			endpoint_bytes_per_packet = 0;

			/* Find the endpoint with the number specified in the VS header */
			for (ep_idx = 0; ep_idx < altsetting->bNumEndpoints; ep_idx++) {
				endpoint = altsetting->endpoint + ep_idx;
				if (endpoint->bEndpointAddress == format_desc->parent->bEndpointAddress) {
					endpoint_bytes_per_packet = endpoint->wMaxPacketSize;
					// wMaxPacketSize: [unused:2 (multiplier-1):3 size:11]
					// bit10…0:		maximum packet size
					// bit12…11:	the number of additional transaction opportunities per microframe for high-speed
					//				00 = None (1 transaction per microframe)
					//				01 = 1 additional (2 per microframe)
					//				10 = 2 additional (3 per microframe)
					//				11 = Reserved
					endpoint_bytes_per_packet
						= (endpoint_bytes_per_packet & 0x07ff)
							* (((endpoint_bytes_per_packet >> 11) & 3) + 1);
					break;
				}
			}
			// XXX config_bytes_per_packet should not be zero otherwise zero divided exception occur
			if (LIKELY(endpoint_bytes_per_packet)) {
				if ( (endpoint_bytes_per_packet >= config_bytes_per_packet)
					|| (alt_idx == num_alt) ) {	// XXX always match to last altsetting for buggy device
					/* Transfers will be at most one frame long: Divide the maximum frame size
					 * by the size of the endpoint and round up */
					packets_per_transfer = (dwMaxVideoFrameSize
							+ endpoint_bytes_per_packet - 1)
							/ endpoint_bytes_per_packet;		// XXX cashed by zero divided exception occured

					/* But keep a reasonable limit: Otherwise we start dropping data */
					if (packets_per_transfer > 32)
						packets_per_transfer = 32;

					total_transfer_size = packets_per_transfer * endpoint_bytes_per_packet;
					break;
				}
			}
		}
		if (UNLIKELY(!endpoint_bytes_per_packet)) {
			LOGE("endpoint_bytes_per_packet is zero");
			ret = UVC_ERROR_INVALID_MODE;
			goto fail;
		}
		if (UNLIKELY(!total_transfer_size)) {
			LOGE("total_transfer_size is zero");
			ret = UVC_ERROR_INVALID_MODE;
			goto fail;
		}

		/* If we searched through all the altsettings and found nothing usable */
/*		if (UNLIKELY(alt_idx == interface->num_altsetting)) {	// XXX never hit this condition
			UVC_DEBUG("libusb_set_interface_alt_setting failed");
			ret = UVC_ERROR_INVALID_MODE;
			goto fail;
		} */

		/* Select the altsetting */
		MARK("Select the altsetting");
		ret = libusb_set_interface_alt_setting(strmh->devh->usb_devh,
				altsetting->bInterfaceNumber, altsetting->bAlternateSetting);
		if (UNLIKELY(ret != UVC_SUCCESS)) {
			UVC_DEBUG("libusb_set_interface_alt_setting failed");
			goto fail;
		}

		/* Set up the transfers */
		MARK("Set up the transfers");
		for (transfer_id = 0; transfer_id < LIBUVC_NUM_TRANSFER_BUFS; ++transfer_id) {
			transfer = libusb_alloc_transfer(packets_per_transfer);
			strmh->transfers[transfer_id] = transfer;
			strmh->transfer_bufs[transfer_id] = malloc(total_transfer_size);

			libusb_fill_iso_transfer(transfer, strmh->devh->usb_devh,
				format_desc->parent->bEndpointAddress,
				strmh->transfer_bufs[transfer_id], total_transfer_size,
				packets_per_transfer, _uvc_stream_callback,
				(void*) strmh, 5000);

			libusb_set_iso_packet_lengths(transfer, endpoint_bytes_per_packet);
		}
	} else {
		MARK("bulk transfer mode");
		/** prepare for bulk transfer */
		for (transfer_id = 0; transfer_id < LIBUVC_NUM_TRANSFER_BUFS; ++transfer_id) {
			transfer = libusb_alloc_transfer(0);
			strmh->transfers[transfer_id] = transfer;
			strmh->transfer_bufs[transfer_id] = malloc(strmh->cur_ctrl.dwMaxPayloadTransferSize);
			libusb_fill_bulk_transfer(transfer, strmh->devh->usb_devh,
				format_desc->parent->bEndpointAddress,
				strmh->transfer_bufs[transfer_id],
				strmh->cur_ctrl.dwMaxPayloadTransferSize, _uvc_stream_callback,
				(void *)strmh, 5000);
		}
	}

	strmh->user_cb = cb;
	strmh->user_ptr = user_ptr;

	/* If the user wants it, set up a thread that calls the user's function
	 * with the contents of each frame.
	 */
	MARK("create callback thread");
	if LIKELY(cb) {
		pthread_create(&strmh->cb_thread, NULL, _uvc_user_caller, (void*) strmh);
	}
	MARK("submit transfers");
	for (transfer_id = 0; transfer_id < LIBUVC_NUM_TRANSFER_BUFS; transfer_id++) {
		ret = libusb_submit_transfer(strmh->transfers[transfer_id]);
		if (UNLIKELY(ret != UVC_SUCCESS)) {
			UVC_DEBUG("libusb_submit_transfer failed");
			break;
		}
	}

	if (UNLIKELY(ret != UVC_SUCCESS)) {
		/** @todo clean up transfers and memory */
		goto fail;
	}

	UVC_EXIT(ret);
	return ret;
fail:
	LOGE("fail");
	strmh->running = 0;
	UVC_EXIT(ret);
	return ret;
}

/** Begin streaming video from the stream into the callback function.
 * @ingroup streaming
 *
 * @deprecated The stream type (bulk vs. isochronous) will be determined by the
 * type of interface associated with the uvc_stream_ctrl_t parameter, regardless
 * of whether the caller requests isochronous streaming. Please switch to
 * uvc_stream_start().
 *
 * @param strmh UVC stream
 * @param cb   User callback function. See {uvc_frame_callback_t} for restrictions.
 */
uvc_error_t uvc_stream_start_iso(uvc_stream_handle_t *strmh,
		uvc_frame_callback_t *cb, void *user_ptr) {
	return uvc_stream_start(strmh, cb, user_ptr, 0);
}

/** @internal
 * @brief User callback runner thread
 * @note There should be at most one of these per currently streaming device
 * @param arg Device handle
 */
static void *_uvc_user_caller(void *arg) {
	uvc_stream_handle_t *strmh = (uvc_stream_handle_t *) arg;

	uint32_t last_seq = 0;

	for (; 1 ;) {
		pthread_mutex_lock(&strmh->cb_mutex);
		{
			for (; strmh->running && (last_seq == strmh->hold_seq) ;) {
				pthread_cond_wait(&strmh->cb_cond, &strmh->cb_mutex);
			}

			if (UNLIKELY(!strmh->running)) {
				pthread_mutex_unlock(&strmh->cb_mutex);
				break;
			}

			last_seq = strmh->hold_seq;
			if (LIKELY(!strmh->hold_bfh_err))	// XXX
				_uvc_populate_frame(strmh);
		}
		pthread_mutex_unlock(&strmh->cb_mutex);

		if (LIKELY(!strmh->hold_bfh_err))	// XXX
			strmh->user_cb(&strmh->frame, strmh->user_ptr);	// call user callback function
	}

	return NULL; // return value ignored
}

/** @internal
 * @brief Populate the fields of a frame to be handed to user code
 * must be called with stream cb lock held!
 */
void _uvc_populate_frame(uvc_stream_handle_t *strmh) {
	size_t alloc_size = strmh->cur_ctrl.dwMaxVideoFrameSize;
	uvc_frame_t *frame = &strmh->frame;
	uvc_frame_desc_t *frame_desc;

	/** @todo this stuff that hits the main config cache should really happen
	 * in start() so that only one thread hits these data. all of this stuff
	 * is going to be reopen_on_change anyway
	 */

	frame_desc = uvc_find_frame_desc(strmh->devh, strmh->cur_ctrl.bFormatIndex,
			strmh->cur_ctrl.bFrameIndex);

	frame->frame_format = strmh->frame_format;

	frame->width = frame_desc->wWidth;
	frame->height = frame_desc->wHeight;
	// XXX set actual_bytes to zero when erro bits is on
	frame->actual_bytes = LIKELY(!strmh->hold_bfh_err) ? strmh->hold_bytes : 0;

	switch (frame->frame_format) {
	case UVC_FRAME_FORMAT_YUYV:
		frame->step = frame->width * 2;
		break;
	case UVC_FRAME_FORMAT_MJPEG:
		frame->step = 0;
		break;
	default:
		frame->step = 0;
		break;
	}

	/* copy the image data from the hold buffer to the frame (unnecessary extra buf?) */
	if (UNLIKELY(frame->data_bytes < strmh->hold_bytes)) {
		frame->data = realloc(frame->data, strmh->hold_bytes);	// TODO add error handling when failed realloc
		frame->data_bytes = strmh->hold_bytes;
	}
	memcpy(frame->data, strmh->holdbuf, strmh->hold_bytes/*frame->data_bytes*/);	// XXX

	/** @todo set the frame time */
}

/** Poll for a frame
 * @ingroup streaming
 *
 * @param devh UVC device
 * @param[out] frame Location to store pointer to captured frame (NULL on error)
 * @param timeout_us >0: Wait at most N microseconds; 0: Wait indefinitely; -1: return immediately
 */
uvc_error_t uvc_stream_get_frame(uvc_stream_handle_t *strmh,
		uvc_frame_t **frame, int32_t timeout_us) {
	time_t add_secs;
	time_t add_nsecs;
	struct timespec ts;
	struct timeval tv;

	if (UNLIKELY(!strmh->running))
		return UVC_ERROR_INVALID_PARAM;

	if (UNLIKELY(strmh->user_cb))
		return UVC_ERROR_CALLBACK_EXISTS;

	pthread_mutex_lock(&strmh->cb_mutex);
	{
		if (strmh->last_polled_seq < strmh->hold_seq) {
			_uvc_populate_frame(strmh);
			*frame = &strmh->frame;
			strmh->last_polled_seq = strmh->hold_seq;
		} else if (timeout_us != -1) {
			if (!timeout_us) {
				pthread_cond_wait(&strmh->cb_cond, &strmh->cb_mutex);
			} else {
				add_secs = timeout_us / 1000000;
				add_nsecs = (timeout_us % 1000000) * 1000;
				ts.tv_sec = 0;
				ts.tv_nsec = 0;

#if _POSIX_TIMERS > 0
				clock_gettime(CLOCK_REALTIME, &ts);
#else
				gettimeofday(&tv, NULL);
				ts.tv_sec = tv.tv_sec;
				ts.tv_nsec = tv.tv_usec * 1000;
#endif

				ts.tv_sec += add_secs;
				ts.tv_nsec += add_nsecs;

				pthread_cond_timedwait(&strmh->cb_cond, &strmh->cb_mutex, &ts);
			}

			if (LIKELY(strmh->last_polled_seq < strmh->hold_seq)) {
				_uvc_populate_frame(strmh);
				*frame = &strmh->frame;
				strmh->last_polled_seq = strmh->hold_seq;
			} else {
				*frame = NULL;
			}
		} else {
			*frame = NULL;
		}
	}
	pthread_mutex_unlock(&strmh->cb_mutex);

	return UVC_SUCCESS;
}

/** @brief Stop streaming video
 * @ingroup streaming
 *
 * Closes all streams, ends threads and cancels pollers
 *
 * @param devh UVC device
 */
void uvc_stop_streaming(uvc_device_handle_t *devh) {
	uvc_stream_handle_t *strmh, *strmh_tmp;

	UVC_ENTER();
	DL_FOREACH_SAFE(devh->streams, strmh, strmh_tmp)
	{
		uvc_stream_close(strmh);
	}
	UVC_EXIT_VOID();
}

/** @brief Stop stream.
 * @ingroup streaming
 *
 * Stops stream, ends threads and cancels pollers
 *
 * @param devh UVC device
 */
uvc_error_t uvc_stream_stop(uvc_stream_handle_t *strmh) {

	int i;
	ENTER();

	if (!strmh) RETURN(UVC_SUCCESS, uvc_error_t);

	if (UNLIKELY(!strmh->running)) {
		UVC_EXIT(UVC_ERROR_INVALID_PARAM);
		RETURN(UVC_ERROR_INVALID_PARAM, uvc_error_t);
	}

	strmh->running = 0;

	pthread_mutex_lock(&strmh->cb_mutex);
	{
		for (i = 0; i < LIBUVC_NUM_TRANSFER_BUFS; i++) {
			if (strmh->transfers[i]) {
				int res = libusb_cancel_transfer(strmh->transfers[i]);
				if ((res < 0) && (res != LIBUSB_ERROR_NOT_FOUND)) {
					UVC_DEBUG("libusb_cancel_transfer failed");
					// XXX originally freed buffers and transfer here
					// but this could lead to crash in _uvc_callback
					// therefore we comment out these lines
					// and free these objects in _uvc_iso_callback when strmh->running is false
/*					free(strmh->transfers[i]->buffer);
					libusb_free_transfer(strmh->transfers[i]);
					strmh->transfers[i] = NULL; */
				}
				if (res == LIBUSB_ERROR_NOT_FOUND && strmh->transfers[i] != NULL) {
                    free(strmh->transfers[i]->buffer);
                    // libusb_free_transfer(strmh->transfers[i]);
                    strmh->transfers[i] = NULL;
                }
			}
		}

		/* Wait for transfers to complete/cancel */
		for (; 1 ;) {
			for (i = 0; i < LIBUVC_NUM_TRANSFER_BUFS; i++) {
				if (strmh->transfers[i] != NULL)
					break;
			}
			if (i == LIBUVC_NUM_TRANSFER_BUFS)
				break;

             ts.tv_sec = 0;
             ts.tv_nsec = 0;

#if _POSIX_TIMERS > 0
             clock_gettime(CLOCK_REALTIME, &ts);
#else
             gettimeofday(&tv, NULL);
             ts.tv_sec = tv.tv_sec;
             ts.tv_nsec = tv.tv_usec * 1000;
#endif
             ts.tv_sec += 1;
             ts.tv_nsec += 0;
			if (pthread_cond_timedwait(&strmh->cb_cond, &strmh->cb_mutex, &ts) == ETIMEDOUT) {
                break;
			}
		}
		// Kick the user thread awake
		pthread_cond_broadcast(&strmh->cb_cond);
	}
	pthread_mutex_unlock(&strmh->cb_mutex);

	/** @todo stop the actual stream, camera side? */

	if (strmh->user_cb) {
		/* wait for the thread to stop (triggered by LIBUSB_TRANSFER_CANCELLED transfer) */
		pthread_join(strmh->cb_thread, NULL);
	}

	RETURN(UVC_SUCCESS, uvc_error_t);
}

/** @brief Close stream.
 * @ingroup streaming
 *
 * Closes stream, frees handle and all streaming resources.
 *
 * @param strmh UVC stream handle
 */
void uvc_stream_close(uvc_stream_handle_t *strmh) {
	UVC_ENTER();

	if (!strmh) { UVC_EXIT_VOID() };

	if (strmh->running)
		uvc_stream_stop(strmh);

	uvc_release_if(strmh->devh, strmh->stream_if->bInterfaceNumber);

	if (strmh->frame.data) {
		free(strmh->frame.data);
		strmh->frame.data = NULL;
	}

	if (strmh->outbuf) {
		free(strmh->outbuf);
		strmh->outbuf = NULL;
	}
	if (strmh->holdbuf) {
		free(strmh->holdbuf);
		strmh->holdbuf = NULL;
	}

	pthread_cond_destroy(&strmh->cb_cond);
	pthread_mutex_destroy(&strmh->cb_mutex);

	DL_DELETE(strmh->devh->streams, strmh);
	free(strmh);

	UVC_EXIT_VOID();
}
