/*************************************************************************** Name : DDI.C Copyright (c) Microsoft Corp. 1991 1992 1993 Revision Log Num Date Name Description --- -------- ---------- ----------------------------------------------- ***************************************************************************/ #define USE_DEBUG_CONTEXT DEBUG_CONTEXT_T30_CLASS1 #include "prep.h" #include "mmsystem.h" #include "comdevi.h" #include "class1.h" ///RSL #include "glbproto.h" #include "psslog.h" #define FILE_ID FILE_ID_DDI /* Converts a the T30 code for a speed to the Class1 code * Generates V.17 with Long Training. * Add 1 to V.17 codes to get teh Short-train version */ BYTE T30toC1[16] = { /* V27_2400 0 */ 24, /* V29_9600 1 */ 96, /* V27_4800 2 */ 48, /* V29_7200 3 */ 72, /* V33_14400 4 */ 145, // 144, // V33==V17_long_train FTM=144 is illegal 0, /* V33_12000 6 */ 121, // 120, // V33==V17_long_train FTM=120 is illegal /* V21 squeezed in */ 3, /* V17_14400 8 */ 145, /* V17_9600 9 */ 97, /* V17_12000 10 */ 121, /* V17_7200 11 */ 73, 0, 0, 0, 0 }; CBSZ cbszFTH3 = "AT+FTH=3\r"; CBSZ cbszFRH3 = "AT+FRH=3\r"; CBSZ cbszFTM = "AT+FTM=%d\r"; CBSZ cbszFRM = "AT+FRM=%d\r"; // echo off, verbose response, no auto answer, hangup on DTR drop // 30 seconds timer on connect, speaker always off, speaker volume=0 // busy&dialtone detect enabled extern CBSZ cbszOK ; extern CBSZ cbszCONNECT ; extern CBSZ cbszNOCARRIER ; extern CBSZ cbszERROR ; extern CBSZ cbszFCERROR ; #define ST_MASK (0x8 | ST_FLAG) // 8 selects V17 only. 16 selects ST flag /******************** Global Vars *********/ BYTE bDLEETX[3] = { DLE, ETX, 0 }; BYTE bDLEETXOK[9] = { DLE, ETX, '\r', '\n', 'O', 'K', '\r', '\n', 0 }; /******************** Global Vars *********/ USHORT NCUDial(PThrdGlbl pTG, LPSTR szPhoneNum) { USHORT uRet; _fmemset(&pTG->Class1Modem, 0, sizeof(CLASS1_MODEM)); if((uRet = iModemDial(pTG, szPhoneNum)) == CONNECT_OK) { pTG->Class1Modem.ModemMode = FRH; } return uRet; } USHORT NCULink ( PThrdGlbl pTG, USHORT uFlags ) { USHORT uRet; DEBUG_FUNCTION_NAME(_T("NCULink")); switch(uFlags) { case NCULINK_HANGUP: if(iModemHangup(pTG)) { uRet = CONNECT_OK; } else { uRet = CONNECT_ERROR; } break; case NCULINK_RX: _fmemset(&pTG->Class1Modem, 0, sizeof(CLASS1_MODEM)); if((uRet = iModemAnswer(pTG)) == CONNECT_OK) { pTG->Class1Modem.ModemMode = FTH; } break; default: uRet = CONNECT_ERROR; break; } DebugPrintEx( DEBUG_MSG, "uRet=%d", uRet); return uRet; } // dangerous. May get 2 OKs, may get one. Generally avoid // CBSZ cbszATAT = "AT\rAT\r"; CBSZ cbszAT1 = "AT\r"; BOOL iModemSyncEx(PThrdGlbl pTG, ULONG ulTimeout, DWORD dwFlags) { DEBUG_FUNCTION_NAME(("iModemSyncEx")); ///// Do cleanup of global state ////// FComOutFilterClose(pTG); FComOverlappedIO(pTG, FALSE); FComXon(pTG, FALSE); EndMode(pTG); ///// Do cleanup of global state ////// { LPCMDTAB lpCmdTab = iModemGetCmdTabPtr(pTG); if ( (dwFlags & fMDMSYNC_DCN) && (pTG->Class1Modem.ModemMode == COMMAND) && lpCmdTab && (lpCmdTab->dwFlags&fMDMSP_C1_NO_SYNC_IF_CMD) ) { DebugPrintEx(DEBUG_WRN, "NOT Syching modem (MSPEC)"); Sleep(100); // +++ 4/12 JosephJ -- try to elim this -- it's juse // that we used to always issue an AT here, which // we now don't, so I issue a 100ms delay here instead. // MOST probably unnessary. The AT was issued by // accident on 4/94 -- as a side effect of // a change in T.30 code -- when iModemSyncEx was // called just before a normal dosconnect. Unfortunately // we discovered in 4/95, 2 weeks before code freeze, // that the AT&T DataPort express (TT14), didn't // like this AT. return TRUE; } else { return (iModemPauseDialog(pTG, (LPSTR)cbszAT1, sizeof(cbszAT1)-1, ulTimeout, cbszOK)==1); } } } // length of TCF = 1.5 * bpscode * 100 / 8 == 75 * bpscode / 4 USHORT TCFLen[16] = { /* V27_2400 0 */ 450, /* V29_9600 1 */ 1800, /* V27_4800 2 */ 900, /* V29_7200 3 */ 1350, /* V33_14400 4 */ 2700, 0, /* V33_12000 6 */ 2250, 0, /* V17_14400 8 */ 2700, /* V17_9600 9 */ 1800, /* V17_12000 10 */ 2250, /* V17_7200 11 */ 1350, 0, 0, 0, 0 }; #define min(x,y) (((x) < (y)) ? (x) : (y)) #define ZERO_BUFSIZE 256 void SendZeros1(PThrdGlbl pTG, USHORT uCount) { BYTE bZero[ZERO_BUFSIZE]; short i; // must be signed DEBUG_FUNCTION_NAME(_T("SendZeros1")); PSSLogEntry(PSS_MSG, 2, "send: %d zeroes", uCount); _fmemset(bZero, 0, ZERO_BUFSIZE); for(i=uCount; i>0; i -= ZERO_BUFSIZE) { // no need to stuff. They're all zeros! FComDirectAsyncWrite(pTG, bZero, (UWORD)(min((UWORD)i, (UWORD)ZERO_BUFSIZE))); } DebugPrintEx(DEBUG_MSG,"Sent %d zeros",uCount); } BOOL ModemSendMode ( PThrdGlbl pTG, USHORT uMod ) { DEBUG_FUNCTION_NAME(_T("ModemSendMode")); pTG->Class1Modem.CurMod = T30toC1[uMod & 0xF]; if((uMod & ST_MASK) == ST_MASK) // mask selects V.17 and ST bits { pTG->Class1Modem.CurMod++; } DebugPrintEx( DEBUG_MSG, "uMod=%d CurMod=%d", uMod, pTG->Class1Modem.CurMod); if(uMod == V21_300) { _fstrcpy(pTG->Class1Modem.bCmdBuf, (LPSTR)cbszFTH3); pTG->Class1Modem.uCmdLen = sizeof(cbszFTH3)-1; pTG->Class1Modem.fHDLC = TRUE; FComXon(pTG, FALSE); // for safety. _May_ be critical } else { pTG->Class1Modem.uCmdLen = (USHORT)wsprintf(pTG->Class1Modem.bCmdBuf, cbszFTM, pTG->Class1Modem.CurMod); pTG->Class1Modem.fHDLC = FALSE; FComXon(pTG, TRUE); // critical!! Start of PhaseC // no harm doing it here(i.e before issuing +FTM) } FComOutFilterInit(pTG); // _not_ used for 300bps HDLC // but here just in case // want to do all the work _before_ issuing command pTG->Class1Modem.DriverMode = SEND; if(pTG->Class1Modem.ModemMode == FTH) { // already in send mode. This happens on Answer only return TRUE; } #define STARTSENDMODE_TIMEOUT 5000 // Random Timeout //// Try to cut down delay between getting CONNECT and writing the // first 00s (else modems can quit because of underrun). // Can do this by not sleeping in this. Only in fatal // cases will it lock up for too long (max 5secs). In those cases // the call is trashed too. if(!iModemNoPauseDialog(pTG, (LPB)pTG->Class1Modem.bCmdBuf, pTG->Class1Modem.uCmdLen, STARTSENDMODE_TIMEOUT, cbszCONNECT)) { goto error; } // can't set this earlier. We'll trash previous value pTG->Class1Modem.ModemMode = ((uMod==V21_300) ? FTH : FTM); // Turn OFF overlapped I/O if in V.21 else ON FComOverlappedIO(pTG, uMod != V21_300); if(pTG->Class1Modem.ModemMode == FTM) { // don't send 00s if ECM SendZeros1(pTG, (USHORT)(TCFLen[uMod & 0x0F] / PAGE_PREAMBLE_DIV)); } // FComDrain(-,FALSE) causes fcom to write out any internally- // maintained buffers, but not to drain the comm-driver buffers. FComDrain(pTG, TRUE,FALSE); DebugPrintEx( DEBUG_MSG, "Starting Send at %d", pTG->Class1Modem.CurMod); return TRUE; error: FComOutFilterClose(pTG); FComOverlappedIO(pTG, FALSE); FComXon(pTG, FALSE); // important. Cleanup on error EndMode(pTG); return FALSE; } BOOL iModemDrain(PThrdGlbl pTG) { DEBUG_FUNCTION_NAME(_T("iModemDrain")); if(!FComDrain(pTG, TRUE, TRUE)) return FALSE; // Must turn XON/XOFF off immediately *after* drain, but before we // send the next AT command, since recieved frames have 0x13 or // even 0x11 in them!! MUST GO AFTER the getOK ---- See BELOW!!!! // increase this---see bug number 495. Must be big enough for // COM_OUTBUFSIZE to safely drain at 2400bps(300bytes/sec = 0.3bytes/ms) // let's say (COM_OUTBUFSIZE * 10 / 3) == (COM_OUTBUFSIZE * 4) // can be quite long, because on failure we just barf anyway #define POSTPAGEOK_TIMEOUT (10000L + (((ULONG)COM_OUTBUFSIZE) << 2)) // Here we were looking for OK only, but some modems (UK Cray Quantun eg) // give me an ERROR after sending TCF or a page (at speeds < 9600) even // though the page was sent OK. So we were timing out here. Instead look // for ERROR (and NO CARRIER too--just in case!), and accept those as OK // No point returning ERROR from here, since we just abort. We can't/don't // recover from send errors if(iModemResp3(pTG, POSTPAGEOK_TIMEOUT, cbszOK, cbszERROR, cbszNOCARRIER) == 0) return FALSE; // Must change FlowControl State *after* getting OK because in Windows // this call takes 500 ms & resets chips, blows away data etc. // So do this *only* when you *know* both RX & TX are empty. // check this in all usages of this function return TRUE; } BOOL iModemSendData(PThrdGlbl pTG, LPB lpb, USHORT uCount, USHORT uFlags) { DEBUG_FUNCTION_NAME(("iModemSendData")); { // always DLE-stuff here. Sometimes zero-stuff DebugPrintEx(DEBUG_MSG,"calling FComFilterAsyncWrite"); if(!FComFilterAsyncWrite(pTG, lpb, uCount, FILTER_DLEZERO)) goto error; } if(uFlags & SEND_FINAL) { DebugPrintEx(DEBUG_MSG,"FComDIRECTAsyncWrite"); PSSLogEntry(PSS_MSG, 2, "send: "); // if(!FComDirectAsyncWrite(bDLEETXCR, 3)) if(!FComDirectAsyncWrite(pTG, bDLEETX, 2)) goto error; if(!iModemDrain(pTG)) goto error; FComOutFilterClose(pTG); FComOverlappedIO(pTG, FALSE); FComXon(pTG, FALSE); // critical. End of PhaseC // must come after Drain EndMode(pTG); } return TRUE; error: FComXon(pTG, FALSE); // critical. End of PhaseC (error) FComFlush(pTG); // clean out the buffer if we got an error FComOutFilterClose(pTG); FComOverlappedIO(pTG, FALSE); EndMode(pTG); return FALSE; } BOOL iModemSendFrame(PThrdGlbl pTG, LPB lpb, USHORT uCount, USHORT uFlags) { UWORD uwResp=0; DEBUG_FUNCTION_NAME(("iModemSendFrame")); // always DLE-stuff here. Never zero-stuff // This is only called for 300bps HDLC if(pTG->Class1Modem.ModemMode != FTH) // Special case on just answering!! { #define FTH_TIMEOUT 5000 // Random Timeout if(!iModemNoPauseDialog( pTG, (LPB)pTG->Class1Modem.bCmdBuf, pTG->Class1Modem.uCmdLen, FTH_TIMEOUT, cbszCONNECT)) goto error; } { // always DLE-stuff here. Never zero-stuff if(!FComFilterAsyncWrite(pTG, lpb, uCount, FILTER_DLEONLY)) goto error; } { PSSLogEntry(PSS_MSG, 2, "send: "); if(!FComDirectAsyncWrite(pTG, bDLEETX, 2)) goto error; } // 2000 is too short because PPRs can be 32+7 bytes long and // preamble is 1 sec, so set this to 3000 // 3000 is too short because NSFs and CSIs can be arbitrarily long // MAXFRAMESIZE is defined in et30type.h. 30ms/byte at 300bps // async (I think V.21 is syn though), so use N*30+1000+slack #define WRITEFRAMERESP_TIMEOUT (1000+30*MAXFRAMESIZE+500) if(!(uwResp = iModemResp2(pTG, WRITEFRAMERESP_TIMEOUT, cbszOK, cbszCONNECT))) goto error; pTG->Class1Modem.ModemMode = ((uwResp == 2) ? FTH : COMMAND); if(uFlags & SEND_FINAL) { FComOutFilterClose(pTG); FComOverlappedIO(pTG, FALSE); // FComXon(FALSE); // at 300bps. no Xon-Xoff in use // in some weird cases (Practical Peripherals PM14400FXMT) we get // CONNECTOK, but we get the CONNECT here. Should we // just set pTG->Class1Modem.ModemMode=COMMAND?? (EndMode does that) // Happens on PP 144FXSA also. Ignore it & just set mode to COMMAND EndMode(pTG); } return TRUE; error: FComOutFilterClose(pTG); FComOverlappedIO(pTG, FALSE); FComXon(pTG, FALSE); // just for safety. cleanup on error EndMode(pTG); return FALSE; } BOOL ModemSendMem ( PThrdGlbl pTG, LPBYTE lpb, USHORT uCount, USHORT uFlags ) { DEBUG_FUNCTION_NAME(_T("ModemSendMem")); DebugPrintEx( DEBUG_MSG, "lpb=%08lx uCount=%d wFlags=%04x", lpb, uCount, uFlags); if(pTG->Class1Modem.DriverMode != SEND) { return FALSE; } if(pTG->Class1Modem.fHDLC) { DebugPrintEx(DEBUG_MSG,"(fHDLC) calling: iModemSendFrame"); return iModemSendFrame(pTG, lpb, uCount, uFlags); } else { DebugPrintEx(DEBUG_MSG,"(Else) calling: iModemSendData"); return iModemSendData(pTG, lpb, uCount, uFlags); } } #define MINRECVMODETIMEOUT 500 #define RECVMODEPAUSE 200 USHORT ModemRecvMode(PThrdGlbl pTG, USHORT uMod, ULONG ulTimeout, BOOL fRetryOnFCERROR) { USHORT uRet; ULONG ulBefore, ulAfter; DEBUG_FUNCTION_NAME(_T("ModemRecvMode")); // Here we should watch for a different modulation scheme from what we expect. // Modems are supposed to return a +FCERROR code to indicate this condition, // but I have not seen it from any modem yet, so we just scan for ERROR // (this will catch +FCERROR too since iiModemDialog does not expect whole // words or anything silly like that!), and treat both the same. pTG->Class1Modem.CurMod = T30toC1[uMod & 0xF]; if((uMod & ST_MASK) == ST_MASK) // mask selects V.17 and ST bits { pTG->Class1Modem.CurMod++; } if(uMod == V21_300) { _fstrcpy(pTG->Class1Modem.bCmdBuf, (LPSTR)cbszFRH3); pTG->Class1Modem.uCmdLen = sizeof(cbszFRH3)-1; } else { pTG->Class1Modem.uCmdLen = (USHORT)wsprintf(pTG->Class1Modem.bCmdBuf, cbszFRM, pTG->Class1Modem.CurMod); } if(pTG->Class1Modem.ModemMode == FRH) { // already in receive mode. This happens upon Dial only pTG->Class1Modem.fHDLC = TRUE; pTG->Class1Modem.DriverMode = RECV; FComInFilterInit(pTG); return RECV_OK; } // On Win32, we have a problem going into 2400baud recv. // +++ remember to put this into iModemFRHorM when that code is enabled. if (pTG->Class1Modem.CurMod==24) Sleep(80); retry: ulBefore=GetTickCount(); // Don't look for NO CARRIER. Want it to retry until FRM timeout on NO CARRIER // ----This is changed. See below---- uRet = iModemNoPauseDialog3(pTG, pTG->Class1Modem.bCmdBuf, pTG->Class1Modem.uCmdLen, ulTimeout, cbszCONNECT, cbszFCERROR, cbszNOCARRIER); // uRet = iModemNoPauseDialog2(pTG->Class1Modem.bCmdBuf, pTG->Class1Modem.uCmdLen, ulTimeout, cbszCONNECT, cbszFCERROR); ulAfter=GetTickCount(); if((fRetryOnFCERROR && uRet==2) || uRet==3) // uRet==FCERROR or uRet==NOCARRIER { if( (ulAfter <= ulBefore) || // wraparound or 0 time elapsed (timer broke) (ulTimeout < ((ulAfter-ulBefore) + MINRECVMODETIMEOUT))) { DebugPrintEx( DEBUG_WRN, "Giving up on RecvMode. uRet=%d ulTimeout=%ld", uRet, ulTimeout); } else { ulTimeout -= (ulAfter-ulBefore); // need this pause for NO CARRIER for USR modems. See bug#1516 // for the RC229DP, dunno if it's reqd because I dunno why theyre // giving the FCERROR. Don't want to miss the carrier so currently // don't pause. (Maybe we can achieve same effect by simply taking // FCERROR out of the response list above--but that won't work for // NOCARRIER because we _need_ teh pause. iiModemDialog is too fast) if(uRet == 3) Sleep(RECVMODEPAUSE); goto retry; } } DebugPrintEx( DEBUG_MSG, "uMod=%d CurMod=%dulTimeout=%ld: Got=%d", uMod, pTG->Class1Modem.CurMod, ulTimeout, uRet); if(uRet != 1) { EndMode(pTG); if(uRet == 2) { DebugPrintEx( DEBUG_WRN, "Got FCERROR after %ldms", ulAfter-ulBefore); return RECV_WRONGMODE; // need to return quickly } else { DebugPrintEx( DEBUG_WRN, "Got Timeout after %ldms", ulAfter-ulBefore); return RECV_TIMEOUT; } } if(uMod==V21_300) { pTG->Class1Modem.ModemMode = FRH; pTG->Class1Modem.fHDLC = TRUE; } else { pTG->Class1Modem.ModemMode = FRM; pTG->Class1Modem.fHDLC = FALSE; } pTG->Class1Modem.DriverMode = RECV; FComInFilterInit(pTG); DebugPrintEx(DEBUG_MSG, "Starting Recv at %d", pTG->Class1Modem.CurMod); return RECV_OK; } USHORT iModemRecvData ( PThrdGlbl pTG, LPB lpb, USHORT cbMax, ULONG ulTimeout, USHORT far* lpcbRecv ) { SWORD swEOF; USHORT uRet; DEBUG_FUNCTION_NAME(("iModemRecvData")); startTimeOut(pTG, &(pTG->Class1Modem.toRecv), ulTimeout); // 4th arg must be FALSE for Class1 *lpcbRecv = FComFilterReadBuf(pTG, lpb, cbMax, &(pTG->Class1Modem.toRecv), FALSE, &swEOF); if(swEOF == -1) { // we got a DLE-ETX _not_ followed by OK or NO CARRIER. So now // we have to decide whether to (a) declare end of page (swEOF=1) // or (b) ignore it & assume page continues on (swEOF=0). // // The problem is that some modems produce spurious EOL during a page // I believe this happens due a momentary loss of carrier that they // recover from. For example IFAX sending to the ATI 19200. In those // cases we want to do (b). The opposite problem is that we'll run // into a modem whose normal response is other than OK or NO CARRIER. // Then we want to do (a) because otherwise we'll _never_ work with // that modem. // // So we have to either do (a) always, or have an INI setting that // can force (a), which could be set thru the AWMODEM.INF file. But // we also want to do (b) if possible because otehrwise we'll not be // able to recieve from weak or flaky modems or machines or whatever // // Snowball does (b). I believe best soln is an INI setting, with (b) // as default // option (a) // swEOF = 1; // option (b) DebugPrintEx(DEBUG_WRN,"Got arbitrary DLE-ETX. Ignoring"); swEOF = 0; } switch(swEOF) { case 1: uRet = RECV_EOF; break; case 0: return RECV_OK; default: // fall through case -2: uRet = RECV_ERROR; break; case -3: uRet = RECV_TIMEOUT; break; } EndMode(pTG); return uRet; } const static BYTE LFCRETXDLE[4] = { LF, CR, ETX, DLE }; USHORT iModemRecvFrame ( PThrdGlbl pTG, LPB lpb, USHORT cbMax, ULONG ulTimeout, USHORT far* lpcbRecv ) { SWORD swRead, swRet; USHORT i; BOOL fRestarted=0; USHORT uRet; BOOL fGotGoodCRC = 0; // see comment-block below DEBUG_FUNCTION_NAME(_T("iModemRecvFrame")); /** Sometimes modems give use ERROR even when thr frame is good. Happens a lot from Thought to PP144MT on CFR. So we check the CRC. If the CRc was good and everything else looks good _except_ the "ERROR" response from teh modem then return RECV_OK, not RECV_BADFRAME. This should fix BUG#1218 **/ restart: *lpcbRecv=0; if(pTG->Class1Modem.ModemMode!= FRH) { swRet=iModemNoPauseDialog2(pTG, (LPB)pTG->Class1Modem.bCmdBuf, pTG->Class1Modem.uCmdLen, ulTimeout, cbszCONNECT, cbszNOCARRIER); if(swRet==2||swRet==3) { DebugPrintEx(DEBUG_MSG,"Got NO CARRIER from FRH=3"); EndMode(pTG); return RECV_EOF; } else if(swRet != 1) { DebugPrintEx(DEBUG_WRN,"Can't get CONNECT from FRH=3, got %d",swRet); EndMode(pTG); return RECV_TIMEOUT; // may not need this, since we never got flags?? // actually we dont know what the heck we got!! } } /*** Got CONNECT (i.e. flags). Now try to get a frame ***/ /**************************************************************** * Using 3 secs here is a misinterpretation of the T30 CommandReceived? * flowchart. WE want to wait here until we get something or until T2 * or T4 timeout. It would have been best if we started T2 ot T4 on * entry into the search routine (t30.c), but starting it here is good * enough. * Using this 3secs timeout fails when Genoa simulates a bad frame * because Zoom PKT modem gives us a whole raft of bad frames for one * bad PPS-EOP and then gives a CONNECT that we timeout below exactly * as the sender's T4 timeout expires and he re-sends the PPS-EOP * so we miss all of them. * Alternately, we could timeout here on 2sec & retry. But that's risky * If less than 2sec then we'll timeout on modems that give connect * first flag, then 2sec elapse before CR-LF (1sec preamble & 1sec for * long frames, e.g. PPR!) ****************************************************************/ startTimeOut(pTG, &(pTG->Class1Modem.toRecv), ulTimeout); swRead = FComFilterReadLine(pTG, lpb, cbMax, &(pTG->Class1Modem.toRecv)); pTG->Class1Modem.ModemMode = COMMAND; // may change this to FRH if we get CONNECT later. // but set it here just in case we short circuit out due to errors if(swRead<=0) { // Timeout DebugPrintEx(DEBUG_WRN,"Can't get frame after connect. Got-->%d",(WORD)-swRead); D_HexPrint(lpb, (WORD)-swRead); EndMode(pTG); *lpcbRecv = -swRead; return RECV_ERROR; // goto error; } PSSLogEntryHex(PSS_MSG, 2, lpb, swRead, "recv: HDLC frame, %d bytes,", swRead); if (pTG->fLineTooLongWasIgnored) { // the following case is dealt with here: // we get an HDLC frame which is longer than 132 bytes, a bad frame. // the problem is that we might have skipped it and read the 'ERROR' // after it as the actual data. // since no HDLC frame can be that long, let's return an error. // it's important NOT to ask the modem for a response here // we might have already read it. DebugPrintEx(DEBUG_WRN,"the received frame was too long, BAD FRAME!", swRead); (*lpcbRecv) = 0; uRet = RECV_BADFRAME; return uRet; } if (swRead<10) { D_HexPrint(lpb, swRead); } for(i=0, swRead--; i<4 && swRead>=0; i++, swRead--) { if(lpb[swRead] != LFCRETXDLE[i]) break; } // exits when swRead is pointing to last non-noise char // or swRead == -1 // incr by 1 to give actual non-noise data size. // (size = ptr to last byte + 1!) swRead++; // Hack for AT&T AK144 modem that doesn't send us the CRC // only lop off last 2 bytes IFF the frame is >= 5 bytes long // that will leave us at least the FF 03/13 FCF // if(i==4 && swRead>=2) // i.e. found all of DLE-ETX_CR-LF // 09/25/95 This code was changed to never lop of the CRC. // All of the routines except NSxtoBC can figure out the correct length, // and that way if the modem doesn't pass on the CRC, we no longer // lop off the data. // we really want this CRC-checking in the MDDI case too if(i==4)// i.e. found all of DLE-ETX_CR-LF { uRet = RECV_OK; } else { DebugPrintEx(DEBUG_WRN,"Frame doesn't end in dle-etx-cr-lf"); // leave tast two bytes in. We don't *know* it's a CRC, since // frame ending was non-standard uRet = RECV_BADFRAME; } *lpcbRecv = swRead; // check if it is the NULL frame (i.e. DLE-ETX-CR-LF) first. // (check is: swRead==0 and uRet==RECV_OK (see above)) // if so AND if we get OK or CONNECT or ERROR below then ignore // it completely. The Thought modem and the PP144MT generate // this idiotic situation! Keep a flag to avoid a possible // endless loop // broaden this so that we Restart on either a dle-etx-cr-lf // NULL frame or a simple cr-lf NULL frame. But then we need // to return an ERROR (not BADFRAME) after restarting once, // otheriwse there is an infinite loop with T30 calling us // again and again (see bug#834) // chnage yet again. This takes too long, and were trying to tackle // a specific bug (the PP144MT) bug here, so let's retsrat only // on dle-etx-cr-lf (not just cr-lf), and in teh latter case // return a response according to what we get /*** Got Frame. Now try to get OK or ERROR. Timeout=0! ***/ switch(swRet = iModemResp4(pTG,0, cbszOK, cbszCONNECT, cbszNOCARRIER, cbszERROR)) { case 2: pTG->Class1Modem.ModemMode = FRH; // fall through and do exactly like OK!! case 1: // ModemMode already == COMMAND if(swRead<=0 && uRet==RECV_OK && !fRestarted) { DebugPrintEx(DEBUG_WRN,"Got %d after frame. RESTARTING", swRet); fRestarted = 1; goto restart; } //uRet already set break; case 3: // NO CARRIER. If got null-frame or no frame return // RECV_EOF. Otherwise if got OK frame then return RECV_OK // and return frame as usual. Next time around it'll get a // NO CARRIER again (hopefully) or timeout. On a bad frame // we can return RECV_EOF, but this will get into trouble if // the recv is not actually done. Or return BADFRAME, and hope // for a NO CARRIER again next time. But next time we may get a // timeout. ModemMode is always set to COMMAND (already) DebugPrintEx( DEBUG_WRN, "Got NO CARRIER after frame. swRead=%d uRet=%d", swRead, uRet); if(swRead <= 0) uRet = RECV_EOF; // else uRet is already BADFRAME or OK break; // this is bad!! // alternately: // if(swRead<=0 || uRet==RECV_BADFRAME) // { // uRet = RECV_EOF; // *lpcbRecv = 0; // must return 0 bytes with RECV_EOF // } case 4: // ERROR if(swRead<=0) { // got no frame if(uRet==RECV_OK && !fRestarted) { // if we got dle-etx-cr-lf for first time DebugPrintEx( DEBUG_WRN, "Got ERROR after frame. RESTARTING"); fRestarted = 1; goto restart; } else { uRet = RECV_ERROR; } } else { // if everything was OK until we got the "ERROR" response from // the modem and we got a good CRC then treat it as "OK" // This should fix BUG#1218 if(uRet==RECV_OK && fGotGoodCRC) { uRet = RECV_OK; } else { uRet = RECV_BADFRAME; } } DebugPrintEx( DEBUG_WRN, "Got ERROR after frame. swRead=%d uRet=%d", swRead, uRet); break; case 0: // timeout DebugPrintEx( DEBUG_WRN, "Got TIMEOUT after frame. swRead=%d uRet=%d", swRead, uRet); // if everything was OK until we got the timeout from // the modem and we got a good CRC then treat it as "OK" // This should fix BUG#1218 if(uRet==RECV_OK && fGotGoodCRC) { uRet = RECV_OK; } else { uRet = RECV_BADFRAME; } break; } return uRet; } USHORT ModemRecvMem(PThrdGlbl pTG, LPBYTE lpb, USHORT cbMax, ULONG ulTimeout, USHORT far* lpcbRecv) { USHORT uRet; DEBUG_FUNCTION_NAME(_T("ModemRecvMem")); DebugPrintEx( DEBUG_MSG, "lpb=%08lx cbMax=%d ulTimeout=%ld", lpb, cbMax, ulTimeout); if(pTG->Class1Modem.DriverMode != RECV) { return RECV_ERROR; // see bug#1492 } *lpcbRecv=0; if(pTG->Class1Modem.fHDLC) { uRet = iModemRecvFrame(pTG, lpb, cbMax, ulTimeout, lpcbRecv); } else { uRet = iModemRecvData(pTG, lpb, cbMax, ulTimeout, lpcbRecv); } DebugPrintEx( DEBUG_MSG, "lpbf=%08lx uCount=%d uRet=%d", lpb, *lpcbRecv, uRet); return uRet; }