--- sourceforge.net/trunk/rdesktop/cliprdr.c 2003/06/06 09:30:06 392 +++ sourceforge.net/trunk/rdesktop/cliprdr.c 2003/07/01 09:31:25 432 @@ -2,6 +2,7 @@ rdesktop: A Remote Desktop Protocol client. Protocol services - Clipboard functions Copyright (C) Erik Forsberg 2003 + Copyright (C) Matthew Chapman 2003 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -18,684 +19,133 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -#include -#include #include "rdesktop.h" -extern BOOL encryption; -extern Display *display; -extern Window wnd; -extern Time last_gesturetime; - -// static Time selection_timestamp; -static Atom clipboard_atom, primary_atom, targets_atom, timestamp_atom; -static Atom rdesktop_clipboard_target_atom, incr_atom; -static cliprdr_dataformat *server_formats = NULL; -static uint16 num_server_formats = 0; -static XSelectionEvent selection_event; -static uint16 clipboard_channelno; -static Atom targets[NUM_TARGETS]; +#define CLIPRDR_CONNECT 1 +#define CLIPRDR_FORMAT_ANNOUNCE 2 +#define CLIPRDR_FORMAT_ACK 3 +#define CLIPRDR_DATA_REQUEST 4 +#define CLIPRDR_DATA_RESPONSE 5 -static void -cliprdr_print_server_formats(void) -{ -#ifdef WITH_DEBUG_CLIPBOARD - cliprdr_dataformat *this; - uint16 i = 0; - this = server_formats; - DEBUG_CLIPBOARD(("There should be %d server formats.\n", num_server_formats)); - while (NULL != this) - { - DEBUG_CLIPBOARD(("Format code %d\n", this->identifier)); - i++; - this = this->next; - } - DEBUG_CLIPBOARD(("There were %d server formats.\n", i)); -#endif -} -/* -static void -cliprdr_set_selection_timestamp(void) -{ - XEvent xev; - DEBUG_CLIPBOARD(("Changing a property in order to get a timestamp\n")); - fflush(stdout); - XChangeProperty(display, wnd, rdesktop_clipboard_target_atom, - XA_ATOM, 32, PropModeAppend, 0, 0); - DEBUG_CLIPBOARD(("Waiting for PropertyChange on wnd\n")); - fflush(stdout); - XWindowEvent(display, wnd, - PropertyChangeMask, &xev); - DEBUG_CLIPBOARD(("Setting selection_timestamp\n")); - fflush(stdout); - selection_timestamp = xev.xproperty.time; -} -*/ +#define CLIPRDR_REQUEST 0 +#define CLIPRDR_RESPONSE 1 +#define CLIPRDR_ERROR 2 + +static VCHANNEL *cliprdr_channel; static void -cliprdr_send_format_announce(void) +cliprdr_send_packet(uint16 type, uint16 status, uint8 *data, uint32 length) { - DEBUG_CLIPBOARD(("Sending format announce\n")); - STREAM s; - int number_of_formats = 1; - s = sec_init(encryption ? SEC_ENCRYPT : 0, number_of_formats*36+12+4+4); - out_uint32_le(s, number_of_formats*36+12); - out_uint32_le(s, 0x13); - out_uint16_le(s, 2); - out_uint16_le(s, 0); - out_uint32_le(s, number_of_formats*36); - - // out_uint32_le(s, 0xd); // FIXME: This is a rather bogus unicode text description.. - // rdp_out_unistr(s, "", 16); - // out_uint8s(s, 32); - - out_uint32_le(s, 1); // FIXME: This is a rather bogus text description.. - out_uint8s(s, 32); - - out_uint32_le(s, 0); + DEBUG_CLIPBOARD(("CLIPRDR send: type=%d, status=%d, length=%d\n", type, status, length)); + s = channel_init(cliprdr_channel, length + 12); + out_uint16_le(s, type); + out_uint16_le(s, status); + out_uint32_le(s, length); + out_uint8p(s, data, length); + out_uint32(s, 0); /* pad? */ s_mark_end(s); - sec_send_to_channel(s, encryption ? SEC_ENCRYPT : 0, - clipboard_channelno); -} - - -static void -cliprdr_send_empty_datapacket(void) -{ - STREAM out; - out = sec_init(encryption ? SEC_ENCRYPT : 0, - 20); - out_uint32_le(out, 12); - out_uint32_le(out, 0x13); - out_uint16_le(out, 5); - out_uint16_le(out, 1); - out_uint32_le(out, 0); - /* Insert null string here? */ - out_uint32_le(out, 0); - s_mark_end(out); - - sec_send_to_channel(out, encryption ? SEC_ENCRYPT : 0, - clipboard_channelno); + channel_send(s, cliprdr_channel); } - -void -cliprdr_handle_SelectionNotify(XSelectionEvent *event) +void +cliprdr_send_text_format_announce(void) { + uint8 buffer[36]; - unsigned char *data, *datap; - unsigned long nitems, bytes_left; - - unsigned long bytes_left_to_transfer; - int res, i; - - int format; - Atom type_return; - Atom best_target; - Atom *supported_targets; - - STREAM out; - - DEBUG_CLIPBOARD(("cliprdr_handle_SelectionNotify\n")); - - if (None == event->property) { - cliprdr_send_empty_datapacket(); - return; /* Selection failed */ - } - - DEBUG_CLIPBOARD(("selection: %s, target: %s, property: %s\n", - XGetAtomName(display, event->selection), - XGetAtomName(display, event->target), - XGetAtomName(display, event->property))); - - if (targets_atom == event->target) { - /* Response to TARGETS request. Let's find the target - we want and request that */ - res = XGetWindowProperty(display, wnd, - rdesktop_clipboard_target_atom, - 0L, 4096L, False, AnyPropertyType, - &type_return, - &format, &nitems, &bytes_left, &data); - - if (Success != res) - { - DEBUG_CLIPBOARD(("XGetWindowProperty failed!\n")); - cliprdr_send_empty_datapacket(); - return; - } - - if (None == type_return) - /* The owner might no support TARGETS. Just try - STRING */ - best_target = XA_STRING; - else - { - /* FIXME: We should choose format here based - on what the server wanted */ - supported_targets = (Atom *)data; - for (i=0;itime); - - } - else /* Other clipboard data */ - { - - res = XGetWindowProperty(display, wnd, - rdesktop_clipboard_target_atom, - 0L, 0x1FFFFFF, - True, AnyPropertyType, - &type_return, - &format, &nitems, &bytes_left, &data); - - - /* FIXME: We need to handle INCR as well, - this is a temporary solution. */ - - if (incr_atom == type_return) - { - warning("We don't support INCR transfers at this time. Try cutting less data\n"); - cliprdr_send_empty_datapacket(); - } - - - if (Success != res) - { - DEBUG_CLIPBOARD(("XGetWindowProperty failed!\n")); - cliprdr_send_empty_datapacket(); - return; - } - - DEBUG_CLIPBOARD(("Received %d bytes of clipboard data from X, there is %d remaining\n", - nitems, bytes_left)); - DEBUG_CLIPBOARD(("type_return is %s\n", - XGetAtomName(display, type_return))); - - datap = data; - - if (nitems+1 <= MAX_CLIPRDR_STANDALONE_DATASIZE) - { - out = sec_init(encryption ? SEC_ENCRYPT : 0, - 20+nitems+1); - out_uint32_le(out, 12+nitems+1); - out_uint32_le(out, 0x13); - out_uint16_le(out, 5); - out_uint16_le(out, 1); - out_uint32_le(out, nitems+1); - out_uint8p(out, datap, nitems+1); - out_uint32_le(out, 0); - s_mark_end(out); - - sec_send_to_channel(out, encryption ? SEC_ENCRYPT : 0, - clipboard_channelno); - - } - else - { - DEBUG_CLIPBOARD(("Sending %d bytes of data\n", - 16+MAX_CLIPRDR_STANDALONE_DATASIZE)); - out = sec_init(encryption ? SEC_ENCRYPT : 0, - 16+MAX_CLIPRDR_STANDALONE_DATASIZE); - out_uint32_le(out, nitems+12); - out_uint32_le(out, 0x11); - out_uint16_le(out, 5); - out_uint16_le(out, 1); - out_uint32_le(out, nitems); - out_uint8p(out, datap, - MAX_CLIPRDR_STANDALONE_DATASIZE); - s_mark_end(out); - - sec_send_to_channel(out, encryption ? SEC_ENCRYPT : 0, - clipboard_channelno); - - bytes_left_to_transfer = nitems - MAX_CLIPRDR_STANDALONE_DATASIZE; - datap+=MAX_CLIPRDR_STANDALONE_DATASIZE; - - while (bytes_left_to_transfer > MAX_CLIPRDR_STANDALONE_DATASIZE) - { - DEBUG_CLIPBOARD(("Sending %d bytes of data\n", - 16+MAX_CLIPRDR_CONTINUATION_DATASIZE)); - out = sec_init(encryption ? SEC_ENCRYPT : 0, - 8+MAX_CLIPRDR_CONTINUATION_DATASIZE); - out_uint32_le(out, nitems); - out_uint32_le(out, 0x10); - out_uint8p(out, datap, - MAX_CLIPRDR_CONTINUATION_DATASIZE); - s_mark_end(out); - - sec_send_to_channel(out, - encryption ? SEC_ENCRYPT : 0, - clipboard_channelno); - bytes_left_to_transfer-= MAX_CLIPRDR_CONTINUATION_DATASIZE; - datap+=MAX_CLIPRDR_CONTINUATION_DATASIZE; - - } - DEBUG_CLIPBOARD(("Sending %d bytes of data\n", - 12+bytes_left_to_transfer)); - out = sec_init(encryption ? SEC_ENCRYPT : 0, - 12+bytes_left_to_transfer); - out_uint32_le(out, nitems); - out_uint32_le(out, 0x12); - out_uint8p(out, datap, - bytes_left_to_transfer); - out_uint32_le(out, 0x0); - s_mark_end(out); - - sec_send_to_channel(out, encryption ? SEC_ENCRYPT : 0, - clipboard_channelno); - - } - - - XFree(data); - cliprdr_send_format_announce(); - - } - - + buf_out_uint32(buffer, CF_TEXT); + memset(buffer+4, 0, sizeof(buffer)-4); /* description */ + cliprdr_send_packet(CLIPRDR_FORMAT_ANNOUNCE, CLIPRDR_REQUEST, buffer, sizeof(buffer)); } void -cliprdr_handle_SelectionClear(void) +cliprdr_send_blah_format_announce(void) { - DEBUG_CLIPBOARD(("cliprdr_handle_SelectionClear\n")); - cliprdr_send_format_announce(); -} - + uint8 buffer[36]; -static void -cliprdr_request_clipboard_data(uint32 formatcode) -{ - STREAM s; - s = sec_init(encryption ? SEC_ENCRYPT : 0, 24); - out_uint32_le(s, 16); - out_uint32_le(s, 0x13); - out_uint16_le(s, 4); - out_uint16_le(s, 0); - out_uint32_le(s, 4); // Remaining length - out_uint32_le(s, formatcode); - out_uint32_le(s, 0); // Unknown. Garbage pad? - - s_mark_end(s); - - sec_send_to_channel(s, encryption ? SEC_ENCRYPT : 0, - clipboard_channelno); + buf_out_uint32(buffer, CF_OEMTEXT); + memset(buffer+4, 0, sizeof(buffer)-4); /* description */ + cliprdr_send_packet(CLIPRDR_FORMAT_ANNOUNCE, CLIPRDR_REQUEST, buffer, sizeof(buffer)); } - void -cliprdr_handle_SelectionRequest(XSelectionRequestEvent *xevent) +cliprdr_send_native_format_announce(uint8 *data, uint32 length) { - - XSelectionEvent xev; - DEBUG_CLIPBOARD(("cliprdr_handle_SelectionRequest\n")); - DEBUG_CLIPBOARD(("Requestor window id 0x%x ", - (unsigned)xevent->requestor)); - if (clipboard_atom == xevent->selection) { - DEBUG_CLIPBOARD(("wants CLIPBOARD\n")); - } - if (primary_atom == xevent->selection) { - DEBUG_CLIPBOARD(("wants PRIMARY\n")); - } - DEBUG_CLIPBOARD(("Target is %s (0x%x), property is %s (0x%x)\n", - XGetAtomName(display, xevent->target), - (unsigned)xevent->target, - XGetAtomName(display, xevent->property), - (unsigned)xevent->property)); - - xev.type = SelectionNotify; - xev.serial = 0; - xev.send_event = True; - xev.requestor = xevent->requestor; - xev.selection = xevent->selection; - xev.target = xevent->target; - xev.property = xevent->property; - xev.time = xevent->time; - - if (targets_atom == xevent->target) - { - DEBUG_CLIPBOARD(("TARGETS requested, sending list..\n")); - XChangeProperty(display, - xevent->requestor, - xevent->property, - XA_ATOM, - 32, - PropModeAppend, - (unsigned char *)&targets, - NUM_TARGETS); - - XSendEvent(display, - xevent->requestor, - False, - NoEventMask, - (XEvent *)&xev); - return; - } else if (timestamp_atom == xevent->target) - { - XChangeProperty(display, - xevent->requestor, - xevent->property, - XA_INTEGER, - 32, - PropModeAppend, - (unsigned char *)&last_gesturetime, - 1); - XSendEvent(display, - xevent->requestor, - False, - NoEventMask, - (XEvent *)&xev); - } else /* Some other target */ - { - cliprdr_request_clipboard_data(CF_TEXT); - memcpy(&selection_event, &xev, sizeof(xev)); - /* Return and wait for data, handled by - cliprdr_handle_server_data */ - } + cliprdr_send_packet(CLIPRDR_FORMAT_ANNOUNCE, CLIPRDR_REQUEST, data, length); } - -static void -cliprdr_ack_format_list(void) +void +cliprdr_send_data_request(uint32 format) { - STREAM s; - s = sec_init(encryption ? SEC_ENCRYPT : 0, 20); - out_uint32_le(s, 12); - out_uint32_le(s, 0x13); - out_uint16_le(s, 3); - out_uint16_le(s, 1); - out_uint32_le(s, 0); - out_uint32_le(s, 0x0000c0da); - - s_mark_end(s); + uint8 buffer[4]; - sec_send_to_channel(s, encryption ? SEC_ENCRYPT : 0, - clipboard_channelno); + buf_out_uint32(buffer, format); + cliprdr_send_packet(CLIPRDR_DATA_REQUEST, CLIPRDR_REQUEST, buffer, sizeof(buffer)); } - - - - -static void -cliprdr_register_server_formats(STREAM s) +void +cliprdr_send_data(uint8 *data, uint32 length) { - uint32 remaining_length, pad; - uint16 num_formats; - cliprdr_dataformat *this, *next; - - DEBUG_CLIPBOARD(("cliprdr_register_server_formats\n")); - in_uint32_le(s, remaining_length); - - num_formats = remaining_length / 36; - if (NULL != server_formats) { - this = server_formats; - next = this->next; - while (NULL != next) { - xfree(this); - this = NULL; - this = next; - next = this->next; - } - } - this = xmalloc(sizeof(cliprdr_dataformat)); - this->next = NULL; - server_formats = this; - num_server_formats = num_formats; - while (1 < num_formats) { - in_uint32_le(s, this->identifier); - in_uint8a(s, this->textual_description, 32); - DEBUG_CLIPBOARD(("Stored format description with numeric id %d\n", - this->identifier)); - this-> next = xmalloc(sizeof(cliprdr_dataformat)); - this = this->next; - num_formats--; - } - in_uint32_le(s, this->identifier); - DEBUG_CLIPBOARD(("Stored format description with numeric id %d\n", this->identifier)); - in_uint8a(s, this->textual_description, 32); - this -> next = NULL; - in_uint32_le(s, pad); - cliprdr_print_server_formats(); + cliprdr_send_packet(CLIPRDR_DATA_RESPONSE, CLIPRDR_RESPONSE, data, length); } static void -cliprdr_select_X_clipboards(void) -{ - XSetSelectionOwner(display, primary_atom, wnd, last_gesturetime); - if (wnd != XGetSelectionOwner(display, primary_atom)) - { - warning("Failed to aquire ownership of PRIMARY clipboard\n"); - } - XSetSelectionOwner(display, clipboard_atom, wnd, last_gesturetime); - if (wnd != XGetSelectionOwner(display, clipboard_atom)) - { - warning("Failed to aquire ownership of CLIPBOARD clipboard\n"); - } - -} - - - - - -static void -cliprdr_handle_first_handshake(STREAM s) -{ - uint32 remaining_length, pad; - in_uint32_le(s, remaining_length); - in_uint32_le(s, pad); - DEBUG_CLIPBOARD(("Remaining length in first handshake frm server is %d, pad is %d\n", - remaining_length, pad)); - cliprdr_send_format_announce(); -} - -void cliprdr_handle_server_data(uint32 length, uint32 flags, STREAM s) -{ - static uint32 remaining_length; - static char *data, *datap; - static uint32 bytes_left_to_read; - DEBUG_CLIPBOARD(("In cliprdr_handle_server_data, flags is %d\n", - flags)); - if (3 == flags) /* One-op write, no packets follows */ - { - in_uint32_le(s, remaining_length); - data = s->p; - } else if (1 == flags) /* First of several packets */ - { - in_uint32_le(s, remaining_length); - DEBUG_CLIPBOARD(("Remaining length is %d\n", - remaining_length)); - data = xmalloc(remaining_length); - datap = data; - DEBUG_CLIPBOARD(("Copying first %d bytes\n", - MAX_CLIPRDR_STANDALONE_DATASIZE)); - memcpy(datap, s->p, MAX_CLIPRDR_STANDALONE_DATASIZE); - - datap+=MAX_CLIPRDR_STANDALONE_DATASIZE; - bytes_left_to_read = remaining_length-MAX_CLIPRDR_STANDALONE_DATASIZE; - return; - } else if (0 == flags) - { - DEBUG_CLIPBOARD(("Copying %d middle bytes", - MAX_CLIPRDR_CONTINUATION_DATASIZE)); - memcpy(datap, s->p, MAX_CLIPRDR_CONTINUATION_DATASIZE); - - datap+=MAX_CLIPRDR_CONTINUATION_DATASIZE; - bytes_left_to_read-=MAX_CLIPRDR_CONTINUATION_DATASIZE; - return; - } else if (2 == flags) - { - DEBUG_CLIPBOARD(("Copying last %d bytes\n", - bytes_left_to_read)); - memcpy(datap, s->p, bytes_left_to_read); - } - XChangeProperty(display, - selection_event.requestor, - selection_event.property, - XInternAtom(display, "STRING", False), - 8, - PropModeAppend, - data, - remaining_length-1); - - XSendEvent(display, - selection_event.requestor, - False, - NoEventMask, - (XEvent *)&selection_event); - - if (flags & 0x12) - xfree(data); - -} - -void cliprdr_handle_server_data_request(STREAM s) +cliprdr_process(STREAM s) { - Window selectionowner; - uint32 remaining_length; - uint32 wanted_formatcode, pad; - - in_uint32_le(s, remaining_length); - in_uint32_le(s, wanted_formatcode); - in_uint32_le(s, pad); - - /* FIXME: Check that we support this formatcode */ - - DEBUG_CLIPBOARD(("Request from server for format %d\n", - wanted_formatcode)); - - selectionowner = XGetSelectionOwner(display, primary_atom); - - if (None != selectionowner) - { - - /* FIXME: Perhaps we should check if we are the owner? */ - - XConvertSelection(display, primary_atom, - targets_atom, - rdesktop_clipboard_target_atom, - wnd, CurrentTime); - - /* The rest of the transfer is handled in - cliprdr_handle_SelectionNotify */ - - } else - { - DEBUG_CLIPBOARD(("There were no owner for PRIMARY, sending empty string\n")); // FIXME: Should we always send an empty string? - - cliprdr_send_empty_datapacket(); - } - - -} - + uint16 type, status; + uint32 length, format; + char *data; -void cliprdr_callback(STREAM s, uint16 channelno) -{ - static int failed_clipboard_acks = 0; - struct timeval timeval; - uint32 length, flags; - uint16 ptype0, ptype1; - clipboard_channelno = channelno; - DEBUG_CLIPBOARD(("cliprdr_callback called with channelno %d, clipboard data:\n", channelno)); -#ifdef WITH_DEBUG_CLIPBOARD - // hexdump(s->p, s->end - s->p); -#endif + in_uint16_le(s, type); + in_uint16_le(s, status); in_uint32_le(s, length); - in_uint32_le(s, flags); + data = s->p; - DEBUG_CLIPBOARD(("length is %d, flags are %d\n", length, flags)); + DEBUG_CLIPBOARD(("CLIPRDR recv: type=%d, status=%d, length=%d\n", type, status, length)); - if (3 == flags || 1 == flags) /* Single-write op or first-packet-of-several op */ + if (status == CLIPRDR_ERROR) { - in_uint16_le(s, ptype0); - in_uint16_le(s, ptype1); - DEBUG_CLIPBOARD(("ptype0 is %d, ptype1 is %d\n", ptype0, ptype1)); - if (1 == ptype0 && 0 == ptype1) { - cliprdr_handle_first_handshake(s); - return; - } else if (3 == ptype0 && 1 == ptype1) - { - // Acknowledgment on our format announce. Do we care? Not right now. - // There is a strange pad in this packet that we might need some time, - // but probably not. - DEBUG_CLIPBOARD(("Received format announce ACK\n")); - failed_clipboard_acks = 0; - return; - - } else if (3 == ptype0 && 2 == ptype1) - { - DEBUG_CLIPBOARD(("Received failed clipboard format announce ACK, retrying\n")); - - /* This is a fairly portable way to sleep 1/10 of - a second.. */ - timeval.tv_sec = 0; - timeval.tv_usec = 100; - select(0, NULL, NULL, NULL, &timeval); - if (failed_clipboard_acks < 3) - { - - cliprdr_send_format_announce(); - /* Make sure we don't get stuck in this loop */ - failed_clipboard_acks++; - } - else - { - warning("Reached maximum number of clipboard format announce attempts. Pasting in Windows probably won't work well now.\n"); - } - } else if (2 == ptype0 && 0 == ptype1) + if (type == CLIPRDR_FORMAT_ACK) { - cliprdr_register_server_formats(s); - cliprdr_select_X_clipboards(); - cliprdr_ack_format_list(); + /* FIXME: We seem to get this when we send an announce while the server is + still processing a paste. Try sending another announce. */ + cliprdr_send_text_format_announce(); return; - } else if (5 == ptype0 && 1 == ptype1) - { - cliprdr_handle_server_data(length, flags, s); - } else if (4 == ptype0 && 0 == ptype1) - { - cliprdr_handle_server_data_request(s); } - - } - else + error("CLIPRDR error (type=%d)\n", type); + return; + } + + switch (type) { - DEBUG_CLIPBOARD(("Handling middle or last packet\n")); - cliprdr_handle_server_data(length, flags, s); + case CLIPRDR_CONNECT: + ui_clip_sync(); + break; + case CLIPRDR_FORMAT_ANNOUNCE: + ui_clip_format_announce(data, length); + cliprdr_send_packet(CLIPRDR_FORMAT_ACK, CLIPRDR_RESPONSE, NULL, 0); + return; + case CLIPRDR_FORMAT_ACK: + break; + case CLIPRDR_DATA_REQUEST: + in_uint32_le(s, format); + ui_clip_request_data(format); + break; + case CLIPRDR_DATA_RESPONSE: + ui_clip_handle_data(data, length); + break; + default: + unimpl("CLIPRDR packet type %d\n", type); } } - -void cliprdr_init(void) -{ - primary_atom = XInternAtom(display, "PRIMARY", False); - clipboard_atom = XInternAtom(display, "CLIPBOARD", False); - targets_atom = XInternAtom(display, "TARGETS", False); - timestamp_atom = XInternAtom(display, "TIMESTAMP", False); - rdesktop_clipboard_target_atom = XInternAtom(display, "_RDESKTOP_CLIPBOARD_TARGET", False); - incr_atom = XInternAtom(display, "INCR", False); - targets[0] = targets_atom; - targets[1] = XInternAtom(display, "TEXT", False); - targets[2] = XInternAtom(display, "UTF8_STRING", False); - targets[3] = XInternAtom(display, "text/unicode", False); - targets[4] = XInternAtom(display, "TIMESTAMP", False); - targets[5] = XInternAtom(display, "STRING", False); - +BOOL +cliprdr_init(void) +{ + cliprdr_channel = channel_register("cliprdr", CHANNEL_OPTION_INITIALIZED | CHANNEL_OPTION_ENCRYPT_RDP \ + | CHANNEL_OPTION_COMPRESS_RDP | CHANNEL_OPTION_SHOW_PROTOCOL, cliprdr_process); + return (cliprdr_channel != NULL); }