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- fix the socket inheritance feature

Browse source 
- usedtr will now, if the connection was lost in between, attempt to connect again if there is a rising edge on DTR
- code improvements
- handling of some unused handshake lines was changed a bit

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@3738
This commit is contained in:
Ralf Grillenberger 2011-07-30 15:36:56 +00:00
parent 361da0de98
commit d3136d14de
2 changed files with 183 additions and 176 deletions
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333
src/hardware/serialport/nullmodem.cpp
View file

@ -52,87 +52,59 @@ CNullModem::CNullModem(Bitu id, CommandLine* cmd):CSerial (id, cmd) {
// 1) when it is client connect to the server not immediately but
// as soon as a modem-aware application is started (DTR is switched on).
// 2) only receive data when DTR is on.
if(getBituSubstring("usedtr:", &bool_temp, cmd)) {
if(bool_temp==1) {
if (getBituSubstring("usedtr:", &bool_temp, cmd)) {
if (bool_temp==1) {
dtrrespect=true;
transparent=true;
DTR_delta=false; // connect immediately when DTR is already 1
}
}
// transparent: don't add additional handshake control.
if(getBituSubstring("transparent:", &bool_temp, cmd)) {
if(bool_temp==1) transparent=true;
if (getBituSubstring("transparent:", &bool_temp, cmd)) {
if (bool_temp==1) transparent=true;
else transparent=false;
}
// telnet: interpret telnet commands.
if(getBituSubstring("telnet:", &bool_temp, cmd)) {
if(bool_temp==1) {
if (getBituSubstring("telnet:", &bool_temp, cmd)) {
if (bool_temp==1) {
transparent=true;
telnet=true;
}
}
// rxdelay: How many milliseconds to wait before causing an
// overflow when the application is unresponsive.
if(getBituSubstring("rxdelay:", &rx_retry_max, cmd)) {
if(!(rx_retry_max<=10000)) {
if (getBituSubstring("rxdelay:", &rx_retry_max, cmd)) {
if (!(rx_retry_max<=10000)) {
rx_retry_max=50;
}
}
// txdelay: How many milliseconds to wait before sending data.
// This reduces network overhead quite a lot.
if(getBituSubstring("txdelay:", &tx_gather, cmd)) {
if(!(tx_gather<=500)) {
if (getBituSubstring("txdelay:", &tx_gather, cmd)) {
if (!(tx_gather<=500)) {
tx_gather=12;
}
}
// port is for both server and client
if(getBituSubstring("port:", &temptcpport, cmd)) {
if(!(temptcpport>0&&temptcpport<65536)) {
if (getBituSubstring("port:", &temptcpport, cmd)) {
if (!(temptcpport>0&&temptcpport<65536)) {
temptcpport=23;
}
}
// socket inheritance
if(getBituSubstring("inhsocket:", &bool_temp, cmd)) {
// socket inheritance (client-alike)
if (getBituSubstring("inhsocket:", &bool_temp, cmd)) {
#ifdef NATIVESOCKETS
if(Netwrapper_GetCapabilities()&NETWRAPPER_TCP_NATIVESOCKET) {
if(bool_temp==1) {
if (Netwrapper_GetCapabilities()&NETWRAPPER_TCP_NATIVESOCKET) {
if (bool_temp==1) {
int sock;
if (control->cmdline->FindInt("-socket",sock,true)) {
dtrrespect=false;
transparent=true;
// custom connect
Bit8u peernamebuf[16];
LOG_MSG("inheritance port: %d",sock);
clientsocket = new TCPClientSocket(sock);
if(!clientsocket->isopen) {
LOG_MSG("Serial%d: Connection failed.",COMNUMBER);
#if SERIAL_DEBUG
log_ser(dbg_aux,"Nullmodem: Connection failed.");
#endif
delete clientsocket;
clientsocket=0;
LOG_MSG("Inheritance socket handle: %d",sock);
if (!ClientConnect(new TCPClientSocket(sock)))
return;
}
clientsocket->SetSendBufferSize(256);
clientsocket->GetRemoteAddressString(peernamebuf);
// transmit the line status
if(!transparent) setRTSDTR(getRTS(), getDTR());
LOG_MSG("Serial%d: Connected to %s",COMNUMBER,peernamebuf);
#if SERIAL_DEBUG
log_ser(dbg_aux,"Nullmodem: Connected to %s",peernamebuf);
#endif
setEvent(SERIAL_POLLING_EVENT, 1);
CSerial::Init_Registers ();
InstallationSuccessful = true;
setCTS(true);
setDSR(true);
setRI (false);
setCD (true);
return;
} else {
LOG_MSG("Serial%d: -socket start parameter missing.",COMNUMBER);
LOG_MSG("Serial%d: -socket parameter missing.",COMNUMBER);
return;
}
}
@ -144,47 +116,44 @@ CNullModem::CNullModem(Bitu id, CommandLine* cmd):CSerial (id, cmd) {
#else
LOG_MSG("Serial%d: socket inheritance not available.", COMNUMBER);
#endif
}
std::string tmpstring;
if(cmd->FindStringBegin("server:",tmpstring,false)) {
// we are a client
const char* hostnamechar=tmpstring.c_str();
size_t hostlen=strlen(hostnamechar)+1;
if(hostlen>sizeof(hostnamebuffer)) {
hostlen=sizeof(hostnamebuffer);
hostnamebuffer[sizeof(hostnamebuffer)-1]=0;
}
memcpy(hostnamebuffer,hostnamechar,hostlen);
clientport=(Bit16u)temptcpport;
if(dtrrespect) {
// we connect as soon as DTR is switched on
setEvent(SERIAL_NULLMODEM_DTR_EVENT, 50);
LOG_MSG("Serial%d: Waiting for DTR...",COMNUMBER);
} else ClientConnect();
} else {
// we are a server
serverport = (Bit16u)temptcpport;
serversocket = new TCPServerSocket(serverport);
if(!serversocket->isopen) return;
LOG_MSG("Serial%d: Nullmodem server waiting for connection on port %d...",
COMNUMBER,serverport);
setEvent(SERIAL_SERVER_POLLING_EVENT, 50);
// normal server/client
std::string tmpstring;
if (cmd->FindStringBegin("server:",tmpstring,false)) {
// we are a client
const char* hostnamechar=tmpstring.c_str();
size_t hostlen=strlen(hostnamechar)+1;
if (hostlen>sizeof(hostnamebuffer)) {
hostlen=sizeof(hostnamebuffer);
hostnamebuffer[sizeof(hostnamebuffer)-1]=0;
}
memcpy(hostnamebuffer,hostnamechar,hostlen);
clientport=(Bit16u)temptcpport;
if (dtrrespect) {
// we connect as soon as DTR is switched on
setEvent(SERIAL_NULLMODEM_DTR_EVENT, 50);
LOG_MSG("Serial%d: Waiting for DTR...",COMNUMBER);
} else if (!ClientConnect(
new TCPClientSocket((char*)hostnamebuffer,(Bit16u)clientport)))
return;
} else {
// we are a server
serverport = (Bit16u)temptcpport;
if (!ServerListen()) return;
}
}
// ....
CSerial::Init_Registers ();
CSerial::Init_Registers();
InstallationSuccessful = true;
setCTS(dtrrespect||transparent);
setDSR(dtrrespect||transparent);
setRI (false);
setCD (dtrrespect);
setRI(false);
setCD(clientsocket > 0); // CD on if connection established
}
CNullModem::~CNullModem () {
if(serversocket) delete serversocket;
if(clientsocket) delete clientsocket;
CNullModem::~CNullModem() {
if (serversocket) delete serversocket;
if (clientsocket) delete clientsocket;
// remove events
for(Bit16u i = SERIAL_BASE_EVENT_COUNT+1;
i <= SERIAL_NULLMODEM_EVENT_COUNT; i++) {
@ -193,9 +162,8 @@ CNullModem::~CNullModem () {
}
void CNullModem::WriteChar(Bit8u data) {
if(clientsocket)clientsocket->SendByteBuffered(data);
if(!tx_block) {
if (clientsocket)clientsocket->SendByteBuffered(data);
if (!tx_block) {
//LOG_MSG("setevreduct");
setEvent(SERIAL_TX_REDUCTION, (float)tx_gather);
tx_block=true;
@ -203,37 +171,75 @@ void CNullModem::WriteChar(Bit8u data) {
}
Bits CNullModem::readChar() {
Bits rxchar = clientsocket->GetcharNonBlock();
if(telnet && rxchar>=0) return TelnetEmulation((Bit8u)rxchar);
else if(rxchar==0xff && !transparent) {// escape char
if (telnet && rxchar>=0) return TelnetEmulation((Bit8u)rxchar);
else if (rxchar==0xff && !transparent) {// escape char
// get the next char
Bits rxchar = clientsocket->GetcharNonBlock();
if(rxchar==0xff) return rxchar; // 0xff 0xff -> 0xff was meant
if (rxchar==0xff) return rxchar; // 0xff 0xff -> 0xff was meant
rxchar&0x1? setCTS(true) : setCTS(false);
rxchar&0x2? setDSR(true) : setDSR(false);
if(rxchar&0x4) receiveByteEx(0x0,0x10);
if (rxchar&0x4) receiveByteEx(0x0,0x10);
return -1; // no "payload" received
} else return rxchar;
}
void CNullModem::ClientConnect(){
bool CNullModem::ClientConnect(TCPClientSocket* newsocket) {
Bit8u peernamebuf[16];
clientsocket = new TCPClientSocket((char*)hostnamebuffer,
(Bit16u)clientport);
if(!clientsocket->isopen) {
LOG_MSG("Serial%d: Connection failed.",idnumber+1);
clientsocket = newsocket;
if (!clientsocket->isopen) {
LOG_MSG("Serial%d: Connection failed.",COMNUMBER);
delete clientsocket;
clientsocket=0;
return;
setCD(false);
return false;
}
clientsocket->SetSendBufferSize(256);
clientsocket->GetRemoteAddressString(peernamebuf);
// transmit the line status
if(!transparent) setRTSDTR(getRTS(), getDTR());
if (!transparent) setRTSDTR(getRTS(), getDTR());
rx_state=N_RX_IDLE;
LOG_MSG("Serial%d: Connected to %s",idnumber+1,peernamebuf);
LOG_MSG("Serial%d: Connected to %s",COMNUMBER,peernamebuf);
setEvent(SERIAL_POLLING_EVENT, 1);
setCD(true);
return true;
}
bool CNullModem::ServerListen() {
// Start the server listen port.
serversocket = new TCPServerSocket(serverport);
if (!serversocket->isopen) return false;
LOG_MSG("Serial%d: Nullmodem server waiting for connection on port %d...",
COMNUMBER,serverport);
setEvent(SERIAL_SERVER_POLLING_EVENT, 50);
setCD(false);
return true;
}
bool CNullModem::ServerConnect() {
// check if a connection is available.
clientsocket=serversocket->Accept();
if (!clientsocket) return false;
Bit8u peeripbuf[16];
clientsocket->GetRemoteAddressString(peeripbuf);
LOG_MSG("Serial%d: A client (%s) has connected.",COMNUMBER,peeripbuf);
#if SERIAL_DEBUG
log_ser(dbg_aux,"Nullmodem: A client (%s) has connected.", peeripbuf);
#endif
clientsocket->SetSendBufferSize(256);
rx_state=N_RX_IDLE;
setEvent(SERIAL_POLLING_EVENT, 1);
// we don't accept further connections
delete serversocket;
serversocket=0;
// transmit the line status
setRTSDTR(getRTS(), getDTR());
if (transparent) setCD(true);
return true;
}
void CNullModem::Disconnect() {
@ -245,11 +251,16 @@ void CNullModem::Disconnect() {
clientsocket=0;
setDSR(false);
setCTS(false);
if(serverport) {
setCD(false);
if (serverport) {
serversocket = new TCPServerSocket(serverport);
if(serversocket->isopen)
if (serversocket->isopen)
setEvent(SERIAL_SERVER_POLLING_EVENT, 50);
else delete serversocket;
} else if (dtrrespect) {
setEvent(SERIAL_NULLMODEM_DTR_EVENT,50);
DTR_delta = getDTR(); // try to reconnect the next time DTR is set
}
}
@ -264,8 +275,8 @@ void CNullModem::handleUpperEvent(Bit16u type) {
updateMSR();
switch(rx_state) {
case N_RX_IDLE:
if(CanReceiveByte()) {
if(doReceive()) {
if (CanReceiveByte()) {
if (doReceive()) {
// a byte was received
rx_state=N_RX_WAIT;
setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
@ -281,13 +292,13 @@ void CNullModem::handleUpperEvent(Bit16u type) {
break;
case N_RX_BLOCKED:
// one timeout tick
if(!CanReceiveByte()) {
if (!CanReceiveByte()) {
rx_retry++;
if(rx_retry>=rx_retry_max) {
if (rx_retry>=rx_retry_max) {
// it has timed out:
rx_retry=0;
removeEvent(SERIAL_RX_EVENT);
if(doReceive()) {
if (doReceive()) {
// read away everything
while(doReceive());
rx_state=N_RX_WAIT;
@ -304,7 +315,7 @@ void CNullModem::handleUpperEvent(Bit16u type) {
// good: we can receive again
removeEvent(SERIAL_RX_EVENT);
rx_retry=0;
if(doReceive()) {
if (doReceive()) {
rx_state=N_RX_FASTWAIT;
setEvent(SERIAL_RX_EVENT, bytetime*0.65f);
} else {
@ -329,11 +340,11 @@ void CNullModem::handleUpperEvent(Bit16u type) {
case N_RX_BLOCKED: // try to receive
case N_RX_WAIT:
case N_RX_FASTWAIT:
if(CanReceiveByte()) {
if (CanReceiveByte()) {
// just works or unblocked
if(doReceive()) {
if (doReceive()) {
rx_retry=0; // not waiting anymore
if(rx_state==N_RX_WAIT) setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
if (rx_state==N_RX_WAIT) setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
else {
// maybe unblocked
rx_state=N_RX_FASTWAIT;
@ -347,7 +358,7 @@ void CNullModem::handleUpperEvent(Bit16u type) {
} else {
// blocking now or still blocked
#if SERIAL_DEBUG
if(rx_state==N_RX_BLOCKED)
if (rx_state==N_RX_BLOCKED)
log_ser(dbg_aux,"Nullmodem: rx still blocked (retry=%d)",rx_retry);
else log_ser(dbg_aux,"Nullmodem: block on continued rx (retry=%d).",rx_retry);
#endif
@ -361,8 +372,8 @@ void CNullModem::handleUpperEvent(Bit16u type) {
}
case SERIAL_TX_EVENT: {
// Maybe echo cirquit works a bit better this way
if(rx_state==N_RX_IDLE && CanReceiveByte() && clientsocket) {
if(doReceive()) {
if (rx_state==N_RX_IDLE && CanReceiveByte() && clientsocket) {
if (doReceive()) {
// a byte was received
rx_state=N_RX_WAIT;
setEvent(SERIAL_RX_EVENT, bytetime*0.9f);
@ -380,25 +391,7 @@ void CNullModem::handleUpperEvent(Bit16u type) {
case SERIAL_SERVER_POLLING_EVENT: {
// As long as nothing is connected to our server poll the
// connection.
clientsocket=serversocket->Accept();
if(clientsocket) {
Bit8u peeripbuf[16];
clientsocket->GetRemoteAddressString(peeripbuf);
LOG_MSG("Serial%d: A client (%s) has connected.",COMNUMBER,peeripbuf);
#if SERIAL_DEBUG
log_ser(dbg_aux,"Nullmodem: A client (%s) has connected.", peeripbuf);
#endif// new socket found...
clientsocket->SetSendBufferSize(256);
rx_state=N_RX_IDLE;
setEvent(SERIAL_POLLING_EVENT, 1);
// we don't accept further connections
delete serversocket;
serversocket=0;
// transmit the line status
setRTSDTR(getRTS(), getDTR());
} else {
if (!ServerConnect()) {
// continue looking
setEvent(SERIAL_SERVER_POLLING_EVENT, 50);
}
@ -406,13 +399,19 @@ void CNullModem::handleUpperEvent(Bit16u type) {
}
case SERIAL_TX_REDUCTION: {
// Flush the data in the transmitting buffer.
if(clientsocket) clientsocket->FlushBuffer();
if (clientsocket) clientsocket->FlushBuffer();
tx_block=false;
break;
}
case SERIAL_NULLMODEM_DTR_EVENT: {
if(getDTR()) ClientConnect();
else setEvent(SERIAL_NULLMODEM_DTR_EVENT,50);
if ((!DTR_delta) && getDTR()) {
// DTR went positive. Try to connect.
if (ClientConnect(new TCPClientSocket((char*)hostnamebuffer,
(Bit16u)clientport)))
break; // no more DTR wait event when connected
}
DTR_delta = getDTR();
setEvent(SERIAL_NULLMODEM_DTR_EVENT,50);
break;
}
}
@ -432,11 +431,11 @@ void CNullModem::updateMSR () {
bool CNullModem::doReceive () {
Bits rxchar = readChar();
if(rxchar>=0) {
if (rxchar>=0) {
receiveByteEx((Bit8u)rxchar,0);
return true;
}
else if(rxchar==-2) {
else if (rxchar==-2) {
Disconnect();
}
return false;
@ -444,7 +443,7 @@ bool CNullModem::doReceive () {
void CNullModem::transmitByte (Bit8u val, bool first) {
// transmit it later in THR_Event
if(first) setEvent(SERIAL_THR_EVENT, bytetime/8);
if (first) setEvent(SERIAL_THR_EVENT, bytetime/8);
else setEvent(SERIAL_TX_EVENT, bytetime);
// disable 0xff escaping when transparent mode is enabled
@ -455,73 +454,73 @@ void CNullModem::transmitByte (Bit8u val, bool first) {
Bits CNullModem::TelnetEmulation(Bit8u data) {
Bit8u response[3];
if(telClient.inIAC) {
if(telClient.recCommand) {
if((data != 0) && (data != 1) && (data != 3)) {
if (telClient.inIAC) {
if (telClient.recCommand) {
if ((data != 0) && (data != 1) && (data != 3)) {
LOG_MSG("Serial%d: Unrecognized telnet option %d",COMNUMBER, data);
if(telClient.command>250) {
if (telClient.command>250) {
/* Reject anything we don't recognize */
response[0]=0xff;
response[1]=252;
response[2]=data; /* We won't do crap! */
if(clientsocket) clientsocket->SendArray(response, 3);
if (clientsocket) clientsocket->SendArray(response, 3);
}
}
switch(telClient.command) {
case 251: /* Will */
if(data == 0) telClient.binary[TEL_SERVER] = true;
if(data == 1) telClient.echo[TEL_SERVER] = true;
if(data == 3) telClient.supressGA[TEL_SERVER] = true;
if (data == 0) telClient.binary[TEL_SERVER] = true;
if (data == 1) telClient.echo[TEL_SERVER] = true;
if (data == 3) telClient.supressGA[TEL_SERVER] = true;
break;
case 252: /* Won't */
if(data == 0) telClient.binary[TEL_SERVER] = false;
if(data == 1) telClient.echo[TEL_SERVER] = false;
if(data == 3) telClient.supressGA[TEL_SERVER] = false;
if (data == 0) telClient.binary[TEL_SERVER] = false;
if (data == 1) telClient.echo[TEL_SERVER] = false;
if (data == 3) telClient.supressGA[TEL_SERVER] = false;
break;
case 253: /* Do */
if(data == 0) {
if (data == 0) {
telClient.binary[TEL_CLIENT] = true;
response[0]=0xff;
response[1]=251;
response[2]=0; /* Will do binary transfer */
if(clientsocket) clientsocket->SendArray(response, 3);
if (clientsocket) clientsocket->SendArray(response, 3);
}
if(data == 1) {
if (data == 1) {
telClient.echo[TEL_CLIENT] = false;
response[0]=0xff;
response[1]=252;
response[2]=1; /* Won't echo (too lazy) */
if(clientsocket) clientsocket->SendArray(response, 3);
if (clientsocket) clientsocket->SendArray(response, 3);
}
if(data == 3) {
if (data == 3) {
telClient.supressGA[TEL_CLIENT] = true;
response[0]=0xff;
response[1]=251;
response[2]=3; /* Will Suppress GA */
if(clientsocket) clientsocket->SendArray(response, 3);
if (clientsocket) clientsocket->SendArray(response, 3);
}
break;
case 254: /* Don't */
if(data == 0) {
if (data == 0) {
telClient.binary[TEL_CLIENT] = false;
response[0]=0xff;
response[1]=252;
response[2]=0; /* Won't do binary transfer */
if(clientsocket) clientsocket->SendArray(response, 3);
if (clientsocket) clientsocket->SendArray(response, 3);
}
if(data == 1) {
if (data == 1) {
telClient.echo[TEL_CLIENT] = false;
response[0]=0xff;
response[1]=252;
response[2]=1; /* Won't echo (fine by me) */
if(clientsocket) clientsocket->SendArray(response, 3);
if (clientsocket) clientsocket->SendArray(response, 3);
}
if(data == 3) {
if (data == 3) {
telClient.supressGA[TEL_CLIENT] = true;
response[0]=0xff;
response[1]=251;
response[2]=3; /* Will Suppress GA (too lazy) */
if(clientsocket) clientsocket->SendArray(response, 3);
if (clientsocket) clientsocket->SendArray(response, 3);
}
break;
default:
@ -532,7 +531,7 @@ Bits CNullModem::TelnetEmulation(Bit8u data) {
telClient.recCommand = false;
return -1; //continue;
} else {
if(data==249) {
if (data==249) {
/* Go Ahead received */
telClient.inIAC = false;
return -1; //continue;
@ -540,7 +539,7 @@ Bits CNullModem::TelnetEmulation(Bit8u data) {
telClient.command = data;
telClient.recCommand = true;
if((telClient.binary[TEL_SERVER]) && (data == 0xff)) {
if ((telClient.binary[TEL_SERVER]) && (data == 0xff)) {
/* Binary data with value of 255 */
telClient.inIAC = false;
telClient.recCommand = false;
@ -548,7 +547,7 @@ Bits CNullModem::TelnetEmulation(Bit8u data) {
}
}
} else {
if(data == 0xff) {
if (data == 0xff) {
telClient.inIAC = true;
return -1;
}
@ -570,14 +569,14 @@ void CNullModem::setBreak (bool /*value*/) {
/* updateModemControlLines(mcr) sets DTR and RTS. **/
/*****************************************************************************/
void CNullModem::setRTSDTR(bool xrts, bool xdtr) {
if(!transparent) {
if (!transparent) {
Bit8u control[2];
control[0]=0xff;
control[1]=0x0;
if(xrts) control[1]|=1;
if(xdtr) control[1]|=2;
if(LCR&LCR_BREAK_MASK) control[1]|=4;
if(clientsocket) clientsocket->SendArray(control, 2);
if (xrts) control[1]|=1;
if (xdtr) control[1]|=2;
if (LCR&LCR_BREAK_MASK) control[1]|=4;
if (clientsocket) clientsocket->SendArray(control, 2);
}
}
void CNullModem::setRTS(bool val) {

26
src/hardware/serialport/nullmodem.h
View file

@ -35,16 +35,8 @@
class CNullModem : public CSerial {
public:
TCPServerSocket* serversocket;
TCPClientSocket* clientsocket;
CNullModem(Bitu id, CommandLine* cmd);
~CNullModem();
bool receiveblock; // It's not a block of data it rather blocks
Bit16u serverport; // we are a server if this is nonzero
Bit16u clientport;
Bit8u hostnamebuffer[128]; // the name passed to us by the user
void updatePortConfig(Bit16u divider, Bit8u lcr);
void updateMSR();
@ -56,6 +48,16 @@ public:
void setDTR(bool val);
void handleUpperEvent(Bit16u type);
private:
TCPServerSocket* serversocket;
TCPClientSocket* clientsocket;
bool receiveblock; // It's not a block of data it rather blocks
Bit16u serverport; // we are a server if this is nonzero
Bit16u clientport;
Bit8u hostnamebuffer[128]; // the name passed to us by the user
Bitu rx_state;
#define N_RX_IDLE 0
#define N_RX_WAIT 1
@ -64,11 +66,17 @@ public:
#define N_RX_DISC 4
bool doReceive();
void ClientConnect();
bool ClientConnect(TCPClientSocket* newsocket);
bool ServerListen();
bool ServerConnect();
void Disconnect();
Bits readChar();
void WriteChar(Bit8u data);
bool DTR_delta; // with dtrrespect, we try to establish a connection
// whenever DTR switches to 1. This variable is
// used to remember the old state.
bool tx_block; // true while the SERIAL_TX_REDUCTION event
// is pending