FreeRDP/channels/server/channels.c

907 lines
20 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Implementation
* Server Channels
*
* Copyright 2011-2012 Vic Lee
* Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <freerdp/constants.h>
#include <freerdp/server/channels.h>
#include <winpr/crt.h>
#include <winpr/synch.h>
#include <winpr/stream.h>
#include "channels.h"
/**
* this is a workaround to force importing symbols
* will need to fix that later on cleanly
*/
#include <freerdp/server/audin.h>
#include <freerdp/server/rdpsnd.h>
#include <freerdp/server/cliprdr.h>
#include <freerdp/server/rdpdr.h>
#include <freerdp/server/drdynvc.h>
void freerdp_channels_dummy()
{
audin_server_context_new(NULL);
audin_server_context_free(NULL);
rdpsnd_server_context_new(NULL);
rdpsnd_server_context_free(NULL);
cliprdr_server_context_new(NULL);
cliprdr_server_context_free(NULL);
rdpdr_server_context_new(NULL);
rdpdr_server_context_free(NULL);
drdynvc_server_context_new(NULL);
drdynvc_server_context_free(NULL);
}
/**
* end of ugly symbols import workaround
*/
#define CREATE_REQUEST_PDU 0x01
#define DATA_FIRST_PDU 0x02
#define DATA_PDU 0x03
#define CLOSE_REQUEST_PDU 0x04
#define CAPABILITY_REQUEST_PDU 0x05
typedef struct wts_data_item
{
UINT16 channel_id;
BYTE* buffer;
UINT32 length;
} wts_data_item;
static void wts_data_item_free(wts_data_item* item)
{
free(item->buffer);
free(item);
}
void* freerdp_channels_server_find_static_entry(const char* name, const char* entry)
{
return NULL;
}
static rdpPeerChannel* wts_get_dvc_channel_by_id(WTSVirtualChannelManager* vcm, UINT32 ChannelId)
{
LIST_ITEM* item;
rdpPeerChannel* channel = NULL;
for (item = vcm->dvc_channel_list->head; item; item = item->next)
{
channel = (rdpPeerChannel*) item->data;
if (channel->channel_id == ChannelId)
break;
}
return channel;
}
static void wts_queue_receive_data(rdpPeerChannel* channel, const BYTE* buffer, UINT32 length)
{
wts_data_item* item;
item = (wts_data_item*) malloc(sizeof(wts_data_item));
ZeroMemory(item, sizeof(wts_data_item));
item->length = length;
item->buffer = malloc(length);
CopyMemory(item->buffer, buffer, length);
WaitForSingleObject(channel->mutex, INFINITE);
list_enqueue(channel->receive_queue, item);
ReleaseMutex(channel->mutex);
SetEvent(channel->receive_event);
}
static void wts_queue_send_item(rdpPeerChannel* channel, wts_data_item* item)
{
WTSVirtualChannelManager* vcm;
vcm = channel->vcm;
item->channel_id = channel->channel_id;
WaitForSingleObject(vcm->mutex, INFINITE);
list_enqueue(vcm->send_queue, item);
ReleaseMutex(vcm->mutex);
SetEvent(vcm->send_event);
}
static int wts_read_variable_uint(wStream* s, int cbLen, UINT32* val)
{
switch (cbLen)
{
case 0:
if (Stream_GetRemainingLength(s) < 1)
return 0;
Stream_Read_UINT8(s, *val);
return 1;
case 1:
if (Stream_GetRemainingLength(s) < 2)
return 0;
Stream_Read_UINT16(s, *val);
return 2;
default:
if (Stream_GetRemainingLength(s) < 4)
return 0;
Stream_Read_UINT32(s, *val);
return 4;
}
}
static void wts_read_drdynvc_capabilities_response(rdpPeerChannel* channel, UINT32 length)
{
UINT16 Version;
if (length < 3)
return;
Stream_Seek_UINT8(channel->receive_data); /* Pad (1 byte) */
Stream_Read_UINT16(channel->receive_data, Version);
DEBUG_DVC("Version: %d", Version);
channel->vcm->drdynvc_state = DRDYNVC_STATE_READY;
}
static void wts_read_drdynvc_create_response(rdpPeerChannel* channel, wStream* s, UINT32 length)
{
UINT32 CreationStatus;
if (length < 4)
return;
Stream_Read_UINT32(s, CreationStatus);
if ((INT32) CreationStatus < 0)
{
DEBUG_DVC("ChannelId %d creation failed (%d)", channel->channel_id, (INT32) CreationStatus);
channel->dvc_open_state = DVC_OPEN_STATE_FAILED;
}
else
{
DEBUG_DVC("ChannelId %d creation succeeded", channel->channel_id);
channel->dvc_open_state = DVC_OPEN_STATE_SUCCEEDED;
}
SetEvent(channel->receive_event);
}
static void wts_read_drdynvc_data_first(rdpPeerChannel* channel, wStream* s, int cbLen, UINT32 length)
{
int value;
value = wts_read_variable_uint(s, cbLen, &channel->dvc_total_length);
if (value == 0)
return;
length -= value;
if (length > channel->dvc_total_length)
return;
Stream_SetPosition(channel->receive_data, 0);
Stream_EnsureRemainingCapacity(channel->receive_data, (int) channel->dvc_total_length);
Stream_Write(channel->receive_data, Stream_Pointer(s), length);
}
static void wts_read_drdynvc_data(rdpPeerChannel* channel, wStream* s, UINT32 length)
{
if (channel->dvc_total_length > 0)
{
if (Stream_GetPosition(channel->receive_data) + length > channel->dvc_total_length)
{
channel->dvc_total_length = 0;
fprintf(stderr, "wts_read_drdynvc_data: incorrect fragment data, discarded.\n");
return;
}
Stream_Write(channel->receive_data, Stream_Pointer(s), length);
if (Stream_GetPosition(channel->receive_data) >= (int) channel->dvc_total_length)
{
wts_queue_receive_data(channel, Stream_Buffer(channel->receive_data), channel->dvc_total_length);
channel->dvc_total_length = 0;
}
}
else
{
wts_queue_receive_data(channel, Stream_Pointer(s), length);
}
}
static void wts_read_drdynvc_close_response(rdpPeerChannel* channel)
{
DEBUG_DVC("ChannelId %d close response", channel->channel_id);
channel->dvc_open_state = DVC_OPEN_STATE_CLOSED;
}
static void wts_read_drdynvc_pdu(rdpPeerChannel* channel)
{
UINT32 length;
int value;
int Cmd;
int Sp;
int cbChId;
UINT32 ChannelId;
rdpPeerChannel* dvc;
length = Stream_GetPosition(channel->receive_data);
if (length < 1)
return;
Stream_SetPosition(channel->receive_data, 0);
Stream_Read_UINT8(channel->receive_data, value);
length--;
Cmd = (value & 0xf0) >> 4;
Sp = (value & 0x0c) >> 2;
cbChId = (value & 0x03) >> 0;
if (Cmd == CAPABILITY_REQUEST_PDU)
{
wts_read_drdynvc_capabilities_response(channel, length);
}
else if (channel->vcm->drdynvc_state == DRDYNVC_STATE_READY)
{
value = wts_read_variable_uint(channel->receive_data, cbChId, &ChannelId);
if (value == 0)
return;
length -= value;
DEBUG_DVC("Cmd %d ChannelId %d length %d", Cmd, ChannelId, length);
dvc = wts_get_dvc_channel_by_id(channel->vcm, ChannelId);
if (dvc)
{
switch (Cmd)
{
case CREATE_REQUEST_PDU:
wts_read_drdynvc_create_response(dvc, channel->receive_data, length);
break;
case DATA_FIRST_PDU:
wts_read_drdynvc_data_first(dvc, channel->receive_data, Sp, length);
break;
case DATA_PDU:
wts_read_drdynvc_data(dvc, channel->receive_data, length);
break;
case CLOSE_REQUEST_PDU:
wts_read_drdynvc_close_response(dvc);
break;
default:
fprintf(stderr, "wts_read_drdynvc_pdu: Cmd %d not recognized.\n", Cmd);
break;
}
}
else
{
DEBUG_DVC("ChannelId %d not exists.", ChannelId);
}
}
else
{
fprintf(stderr, "wts_read_drdynvc_pdu: received Cmd %d but channel is not ready.\n", Cmd);
}
}
static int wts_write_variable_uint(wStream* stream, UINT32 val)
{
int cb;
if (val <= 0xFF)
{
cb = 0;
Stream_Write_UINT8(stream, val);
}
else if (val <= 0xFFFF)
{
cb = 1;
Stream_Write_UINT16(stream, val);
}
else
{
cb = 3;
Stream_Write_UINT32(stream, val);
}
return cb;
}
static void wts_write_drdynvc_header(wStream *s, BYTE Cmd, UINT32 ChannelId)
{
BYTE* bm;
int cbChId;
Stream_GetPointer(s, bm);
Stream_Seek_UINT8(s);
cbChId = wts_write_variable_uint(s, ChannelId);
*bm = ((Cmd & 0x0F) << 4) | cbChId;
}
static void wts_write_drdynvc_create_request(wStream *s, UINT32 ChannelId, const char *ChannelName)
{
UINT32 len;
wts_write_drdynvc_header(s, CREATE_REQUEST_PDU, ChannelId);
len = strlen(ChannelName) + 1;
Stream_EnsureRemainingCapacity(s, (int) len);
Stream_Write(s, ChannelName, len);
}
static void WTSProcessChannelData(rdpPeerChannel* channel, int channelId, BYTE* data, int size, int flags, int total_size)
{
if (flags & CHANNEL_FLAG_FIRST)
{
Stream_SetPosition(channel->receive_data, 0);
}
Stream_EnsureRemainingCapacity(channel->receive_data, size);
Stream_Write(channel->receive_data, data, size);
if (flags & CHANNEL_FLAG_LAST)
{
if (Stream_GetPosition(channel->receive_data) != total_size)
{
fprintf(stderr, "WTSProcessChannelData: read error\n");
}
if (channel == channel->vcm->drdynvc_channel)
{
wts_read_drdynvc_pdu(channel);
}
else
{
wts_queue_receive_data(channel, Stream_Buffer(channel->receive_data), Stream_GetPosition(channel->receive_data));
}
Stream_SetPosition(channel->receive_data, 0);
}
}
static int WTSReceiveChannelData(freerdp_peer* client, int channelId, BYTE* data, int size, int flags, int total_size)
{
int i;
BOOL result = FALSE;
rdpPeerChannel* channel;
for (i = 0; i < client->settings->ChannelCount; i++)
{
if (client->settings->ChannelDefArray[i].ChannelId == channelId)
break;
}
if (i < client->settings->ChannelCount)
{
channel = (rdpPeerChannel*) client->settings->ChannelDefArray[i].handle;
if (channel != NULL)
{
WTSProcessChannelData(channel, channelId, data, size, flags, total_size);
result = TRUE;
}
}
return result;
}
WTSVirtualChannelManager* WTSCreateVirtualChannelManager(freerdp_peer* client)
{
WTSVirtualChannelManager* vcm;
vcm = (WTSVirtualChannelManager*) malloc(sizeof(WTSVirtualChannelManager));
if (vcm)
{
ZeroMemory(vcm, sizeof(WTSVirtualChannelManager));
vcm->client = client;
vcm->send_event = CreateEvent(NULL, TRUE, FALSE, NULL);
vcm->send_queue = list_new();
vcm->mutex = CreateMutex(NULL, FALSE, NULL);
vcm->dvc_channel_id_seq = 1;
vcm->dvc_channel_list = list_new();
client->ReceiveChannelData = WTSReceiveChannelData;
}
return vcm;
}
void WTSDestroyVirtualChannelManager(WTSVirtualChannelManager* vcm)
{
wts_data_item* item;
rdpPeerChannel* channel;
if (vcm != NULL)
{
while ((channel = (rdpPeerChannel*) list_dequeue(vcm->dvc_channel_list)) != NULL)
{
WTSVirtualChannelClose(channel);
}
list_free(vcm->dvc_channel_list);
if (vcm->drdynvc_channel != NULL)
{
WTSVirtualChannelClose(vcm->drdynvc_channel);
vcm->drdynvc_channel = NULL;
}
CloseHandle(vcm->send_event);
while ((item = (wts_data_item*) list_dequeue(vcm->send_queue)) != NULL)
{
wts_data_item_free(item);
}
list_free(vcm->send_queue);
CloseHandle(vcm->mutex);
free(vcm);
}
}
void WTSVirtualChannelManagerGetFileDescriptor(WTSVirtualChannelManager* vcm, void** fds, int* fds_count)
{
void* fd;
fd = GetEventWaitObject(vcm->send_event);
if (fd)
{
fds[*fds_count] = fd;
(*fds_count)++;
}
if (vcm->drdynvc_channel)
{
fd = GetEventWaitObject(vcm->drdynvc_channel->receive_event);
if (fd)
{
fds[*fds_count] = fd;
(*fds_count)++;
}
}
}
BOOL WTSVirtualChannelManagerCheckFileDescriptor(WTSVirtualChannelManager* vcm)
{
BOOL result = TRUE;
wts_data_item* item;
rdpPeerChannel* channel;
UINT32 dynvc_caps;
if (vcm->drdynvc_state == DRDYNVC_STATE_NONE && vcm->client->activated)
{
/* Initialize drdynvc channel once and only once. */
vcm->drdynvc_state = DRDYNVC_STATE_INITIALIZED;
channel = WTSVirtualChannelManagerOpenEx(vcm, "drdynvc", 0);
if (channel)
{
vcm->drdynvc_channel = channel;
dynvc_caps = 0x00010050; /* DYNVC_CAPS_VERSION1 (4 bytes) */
WTSVirtualChannelWrite(channel, (PCHAR) &dynvc_caps, sizeof(dynvc_caps), NULL);
}
}
ResetEvent(vcm->send_event);
WaitForSingleObject(vcm->mutex, INFINITE);
while ((item = (wts_data_item*) list_dequeue(vcm->send_queue)) != NULL)
{
if (vcm->client->SendChannelData(vcm->client, item->channel_id, item->buffer, item->length) == FALSE)
{
result = FALSE;
}
wts_data_item_free(item);
if (result == FALSE)
break;
}
ReleaseMutex(vcm->mutex);
return result;
}
HANDLE WTSVirtualChannelManagerGetEventHandle(WTSVirtualChannelManager* vcm)
{
return vcm->send_event;
}
HANDLE WTSVirtualChannelManagerOpenEx(WTSVirtualChannelManager* vcm, LPSTR pVirtualName, DWORD flags)
{
int i;
int len;
wStream* s;
rdpPeerChannel* channel;
freerdp_peer* client = vcm->client;
if ((flags & WTS_CHANNEL_OPTION_DYNAMIC) != 0)
{
for (i = 0; i < client->settings->ChannelCount; i++)
{
if (client->settings->ChannelDefArray[i].joined &&
strncmp(client->settings->ChannelDefArray[i].Name, "drdynvc", 7) == 0)
{
break;
}
}
if (i >= client->settings->ChannelCount)
{
DEBUG_DVC("Dynamic virtual channel not registered.");
SetLastError(ERROR_NOT_FOUND);
return NULL;
}
if (vcm->drdynvc_channel == NULL || vcm->drdynvc_state != DRDYNVC_STATE_READY)
{
DEBUG_DVC("Dynamic virtual channel not ready.");
SetLastError(ERROR_NOT_READY);
return NULL;
}
channel = (rdpPeerChannel*) malloc(sizeof(rdpPeerChannel));
ZeroMemory(channel, sizeof(rdpPeerChannel));
channel->vcm = vcm;
channel->client = client;
channel->channel_type = RDP_PEER_CHANNEL_TYPE_DVC;
channel->receive_data = Stream_New(NULL, client->settings->VirtualChannelChunkSize);
channel->receive_event = CreateEvent(NULL, TRUE, FALSE, NULL);
channel->receive_queue = list_new();
channel->mutex = CreateMutex(NULL, FALSE, NULL);
WaitForSingleObject(vcm->mutex, INFINITE);
channel->channel_id = vcm->dvc_channel_id_seq++;
list_enqueue(vcm->dvc_channel_list, channel);
ReleaseMutex(vcm->mutex);
s = Stream_New(NULL, 64);
wts_write_drdynvc_create_request(s, channel->channel_id, pVirtualName);
WTSVirtualChannelWrite(vcm->drdynvc_channel, (PCHAR) Stream_Buffer(s), Stream_GetPosition(s), NULL);
Stream_Free(s, TRUE);
DEBUG_DVC("ChannelId %d.%s (total %d)", channel->channel_id, pVirtualName, list_size(vcm->dvc_channel_list));
}
else
{
len = strlen(pVirtualName);
if (len > 8)
{
SetLastError(ERROR_NOT_FOUND);
return NULL;
}
for (i = 0; i < client->settings->ChannelCount; i++)
{
if (client->settings->ChannelDefArray[i].joined &&
strncmp(client->settings->ChannelDefArray[i].Name, pVirtualName, len) == 0)
{
break;
}
}
if (i >= client->settings->ChannelCount)
{
SetLastError(ERROR_NOT_FOUND);
return NULL;
}
channel = (rdpPeerChannel*) client->settings->ChannelDefArray[i].handle;
if (channel == NULL)
{
channel = (rdpPeerChannel*) malloc(sizeof(rdpPeerChannel));
ZeroMemory(channel, sizeof(rdpPeerChannel));
channel->vcm = vcm;
channel->client = client;
channel->channel_id = client->settings->ChannelDefArray[i].ChannelId;
channel->index = i;
channel->channel_type = RDP_PEER_CHANNEL_TYPE_SVC;
channel->receive_data = Stream_New(NULL, client->settings->VirtualChannelChunkSize);
channel->receive_event = CreateEvent(NULL, TRUE, FALSE, NULL);
channel->receive_queue = list_new();
channel->mutex = CreateMutex(NULL, FALSE, NULL);
client->settings->ChannelDefArray[i].handle = channel;
}
}
return channel;
}
BOOL WTSVirtualChannelQuery(HANDLE hChannelHandle, WTS_VIRTUAL_CLASS WtsVirtualClass, PVOID* ppBuffer, DWORD* pBytesReturned)
{
void* pfd;
BOOL bval;
void* fds[10];
int fds_count = 0;
BOOL result = FALSE;
rdpPeerChannel* channel = (rdpPeerChannel*) hChannelHandle;
ZeroMemory(fds, sizeof(fds));
switch (WtsVirtualClass)
{
case WTSVirtualFileHandle:
pfd = GetEventWaitObject(channel->receive_event);
if (pfd)
{
fds[fds_count] = pfd;
(fds_count)++;
}
*ppBuffer = malloc(sizeof(void*));
CopyMemory(*ppBuffer, &fds[0], sizeof(void*));
*pBytesReturned = sizeof(void*);
result = TRUE;
break;
case WTSVirtualEventHandle:
*ppBuffer = malloc(sizeof(HANDLE));
CopyMemory(*ppBuffer, &(channel->receive_event), sizeof(HANDLE));
*pBytesReturned = sizeof(void*);
result = TRUE;
break;
case WTSVirtualChannelReady:
if (channel->channel_type == RDP_PEER_CHANNEL_TYPE_SVC)
{
bval = TRUE;
result = TRUE;
}
else
{
switch (channel->dvc_open_state)
{
case DVC_OPEN_STATE_NONE:
bval = FALSE;
result = TRUE;
break;
case DVC_OPEN_STATE_SUCCEEDED:
bval = TRUE;
result = TRUE;
break;
default:
bval = FALSE;
result = FALSE;
break;
}
}
*ppBuffer = malloc(sizeof(BOOL));
CopyMemory(*ppBuffer, &bval, sizeof(BOOL));
*pBytesReturned = sizeof(BOOL);
break;
default:
break;
}
return result;
}
VOID WTSFreeMemory(PVOID pMemory)
{
free(pMemory);
}
BOOL WTSVirtualChannelRead(HANDLE hChannelHandle, ULONG TimeOut, PCHAR Buffer, ULONG BufferSize, PULONG pBytesRead)
{
wts_data_item* item;
rdpPeerChannel* channel = (rdpPeerChannel*) hChannelHandle;
item = (wts_data_item*) list_peek(channel->receive_queue);
if (!item)
{
ResetEvent(channel->receive_event);
*pBytesRead = 0;
return TRUE;
}
*pBytesRead = item->length;
if (item->length > BufferSize)
return FALSE;
/* remove the first element (same as what we just peek) */
WaitForSingleObject(channel->mutex, INFINITE);
list_dequeue(channel->receive_queue);
if (list_size(channel->receive_queue) == 0)
ResetEvent(channel->receive_event);
ReleaseMutex(channel->mutex);
CopyMemory(Buffer, item->buffer, item->length);
wts_data_item_free(item);
return TRUE;
}
BOOL WTSVirtualChannelWrite(HANDLE hChannelHandle, PCHAR Buffer, ULONG Length, PULONG pBytesWritten)
{
rdpPeerChannel* channel = (rdpPeerChannel*) hChannelHandle;
wts_data_item* item;
wStream* s;
int cbLen;
int cbChId;
int first;
UINT32 written;
if (!channel)
return FALSE;
if (channel->channel_type == RDP_PEER_CHANNEL_TYPE_SVC)
{
item = (wts_data_item*) malloc(sizeof(wts_data_item));
ZeroMemory(item, sizeof(wts_data_item));
item->buffer = malloc(Length);
item->length = Length;
CopyMemory(item->buffer, Buffer, Length);
wts_queue_send_item(channel, item);
}
else if (channel->vcm->drdynvc_channel == NULL || channel->vcm->drdynvc_state != DRDYNVC_STATE_READY)
{
DEBUG_DVC("drdynvc not ready");
return FALSE;
}
else
{
first = TRUE;
while (Length > 0)
{
item = (wts_data_item*) malloc(sizeof(wts_data_item));
ZeroMemory(item, sizeof(wts_data_item));
s = Stream_New(NULL, channel->client->settings->VirtualChannelChunkSize);
item->buffer = Stream_Buffer(s);
Stream_Seek_UINT8(s);
cbChId = wts_write_variable_uint(s, channel->channel_id);
if (first && (Length > (UINT32) Stream_GetRemainingLength(s)))
{
cbLen = wts_write_variable_uint(s, Length);
item->buffer[0] = (DATA_FIRST_PDU << 4) | (cbLen << 2) | cbChId;
}
else
{
item->buffer[0] = (DATA_PDU << 4) | cbChId;
}
first = FALSE;
written = Stream_GetRemainingLength(s);
if (written > Length)
written = Length;
Stream_Write(s, Buffer, written);
item->length = Stream_GetPosition(s);
Stream_Free(s, FALSE);
Length -= written;
Buffer += written;
wts_queue_send_item(channel->vcm->drdynvc_channel, item);
}
}
if (pBytesWritten != NULL)
*pBytesWritten = Length;
return TRUE;
}
BOOL WTSVirtualChannelClose(HANDLE hChannelHandle)
{
wStream* s;
wts_data_item* item;
WTSVirtualChannelManager* vcm;
rdpPeerChannel* channel = (rdpPeerChannel*) hChannelHandle;
if (channel)
{
vcm = channel->vcm;
if (channel->channel_type == RDP_PEER_CHANNEL_TYPE_SVC)
{
if (channel->index < channel->client->settings->ChannelCount)
channel->client->settings->ChannelDefArray[channel->index].handle = NULL;
}
else
{
WaitForSingleObject(vcm->mutex, INFINITE);
list_remove(vcm->dvc_channel_list, channel);
ReleaseMutex(vcm->mutex);
if (channel->dvc_open_state == DVC_OPEN_STATE_SUCCEEDED)
{
s = Stream_New(NULL, 8);
wts_write_drdynvc_header(s, CLOSE_REQUEST_PDU, channel->channel_id);
WTSVirtualChannelWrite(vcm->drdynvc_channel, (PCHAR) Stream_Buffer(s), Stream_GetPosition(s), NULL);
Stream_Free(s, TRUE);
}
}
if (channel->receive_data)
Stream_Free(channel->receive_data, TRUE);
if (channel->receive_event)
CloseHandle(channel->receive_event);
if (channel->receive_queue)
{
while ((item = (wts_data_item*) list_dequeue(channel->receive_queue)) != NULL)
{
wts_data_item_free(item);
}
list_free(channel->receive_queue);
}
if (channel->mutex)
CloseHandle(channel->mutex);
free(channel);
}
return TRUE;
}