diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index eed25509..8b27722b 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -12,19 +12,19 @@ jobs:
           - name: GCC-5 (Ubuntu 16.04)
             os: ubuntu-16.04
             flags: -c gcc
-            max_warnings: 304
+            max_warnings: 289
           - name: GCC-7 (Ubuntu 18.04)
             os: ubuntu-18.04
             flags: -c gcc
-            max_warnings: 307
+            max_warnings: 292
           - name: GCC-9 (Ubuntu 18.04)
             os: ubuntu-18.04
             flags: -c gcc -v 9
-            max_warnings: 330
+            max_warnings: 315
           - name: Clang-8 (Ubuntu 18.04)
             os: ubuntu-18.04
             flags: -c clang -v 8
-            max_warnings: 170
+            max_warnings: 157
     steps:
       - uses: actions/checkout@v1
       - run:  sudo apt-get update
diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index 0c54cc70..88d38fcc 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -11,10 +11,10 @@ jobs:
         conf:
           - name: Clang
             flags: -c clang
-            max_warnings: 222
+            max_warnings: 209
           - name: GCC-9
             flags: -c gcc -v 9
-            max_warnings: 317
+            max_warnings: 302
     steps:
       - uses: actions/checkout@v1
       - name: Install C++ compiler and libraries
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 647cb770..e5032fb6 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -1,10 +1,10 @@
 name: Windows builds
 on: push
 env:
-  MAX_WARNINGS_GCC_32bit_Debug:     234
-  MAX_WARNINGS_GCC_64bit_Debug:     350
-  MAX_WARNINGS_Clang_32bit_Debug:   100
-  MAX_WARNINGS_Clang_64bit_Debug:   155
+  MAX_WARNINGS_GCC_32bit_Debug:     230
+  MAX_WARNINGS_GCC_64bit_Debug:     305
+  MAX_WARNINGS_Clang_32bit_Debug:    99
+  MAX_WARNINGS_Clang_64bit_Debug:   143
 
 jobs:
 
@@ -73,6 +73,5 @@ jobs:
           export MSYSTEM_CARCH="$ARCH_${{ matrix.bits }}"
           export MSYSTEM_CHOST="$ARCH_${{ matrix.bits }}-pc-msys"
           ./scripts/build.sh --compiler ${{ matrix.compiler }} --build-type Debug --bin-path /mingw${{ matrix.bits }}/bin
-          grep '^#define' config.h
       - name:  Debug Warnings
         run:   '.\scripts\count-warnings.py -m $env:MAX_WARNINGS_${{ matrix.compiler }}_${{ matrix.bits }}bit_Debug build.log'
diff --git a/include/types.h b/include/types.h
index b2f0ac64..a3b5a2d7 100644
--- a/include/types.h
+++ b/include/types.h
@@ -22,6 +22,19 @@
 #include <cinttypes>
 #include <cstdint>
 
+/* Work around this bug in /mingw64/x86_64-w64-mingw64/include/inttypes.h:
+ * MS runtime does not yet understand C9x standard "ll"
+ * length specifier. It appears to treat "ll" as "l".
+ * The non-standard I64 length specifier understood by MS
+ * runtime functions, so for now we use that.
+ */
+#if defined(__MINGW64__) && !defined(__clang__)
+#ifdef PRIuPTR
+#undef PRIuPTR
+#endif
+#define PRIuPTR "I64u"
+#endif
+
 using Bit8u  = uint8_t;
 using Bit16u = uint16_t;
 using Bit32u = uint32_t;
diff --git a/scripts/automator/build/clang-defaults b/scripts/automator/build/clang-defaults
index 5792c396..bac59575 100644
--- a/scripts/automator/build/clang-defaults
+++ b/scripts/automator/build/clang-defaults
@@ -4,11 +4,14 @@ cxx="clang++${postfix}"
 
 # Flag additions
 TYPES+=("debug" "profile")
-cflags+=("-fcolor-diagnostics")
 cflags_release=("${cflags[@]}" "-Os")
 cflags_debug=("${cflags[@]}" "-g" "-Og" "-fno-omit-frame-pointer")
 cflags_profile=("${cflags_debug[@]}" "-fprofile-instr-generate" "-fcoverage-mapping")
 
+# Colorize output only for interactive shells
+if [[ $- == *i* ]]; then
+	cflags+=("-fcolor-diagnostics")
+fi
 
 # Modifier additions
 MODIFIERS=("fdo")
diff --git a/scripts/automator/build/gcc-defaults b/scripts/automator/build/gcc-defaults
index aa9e4cff..3674d9f9 100644
--- a/scripts/automator/build/gcc-defaults
+++ b/scripts/automator/build/gcc-defaults
@@ -7,7 +7,7 @@ ranlib="gcc-ranlib${postfix}"
 
 # Flag additions
 TYPES+=("debug" "profile")
-cflags+=("-fstack-protector" "-fdiagnostics-color=always")
+cflags+=("-fstack-protector" "-fdiagnostics-color=auto")
 cflags_release=("${cflags[@]}" "-Ofast" "-ffunction-sections" "-fdata-sections")
 cflags_debug=("${cflags[@]}" "-g" "-Og" "-fno-omit-frame-pointer")
 cflags_profile=("${cflags_debug[@]}" "-pg")
diff --git a/src/hardware/serialport/softmodem.cpp b/src/hardware/serialport/softmodem.cpp
index 10867909..bbacd685 100644
--- a/src/hardware/serialport/softmodem.cpp
+++ b/src/hardware/serialport/softmodem.cpp
@@ -16,62 +16,69 @@
  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-
 #include "dosbox.h"
 
 #if C_MODEM
-
-#include <string.h>
-#include <stdlib.h>
 #include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+#include <utility>
 
 #include "support.h"
 #include "serialport.h"
 #include "softmodem.h"
 #include "misc_util.h"
 
-//#include "mixer.h"
-
-
-CSerialModem::CSerialModem(Bitu id, CommandLine* cmd):CSerial(id, cmd) {
+CSerialModem::CSerialModem(Bitu id, CommandLine* cmd)
+	: CSerial(id, cmd),
+	  rqueue(new CFifo(MODEM_BUFFER_QUEUE_SIZE)),
+	  tqueue(new CFifo(MODEM_BUFFER_QUEUE_SIZE)),
+	  cmdbuf {0},
+	  commandmode(false),
+	  echo(false),
+	  oldDTRstate(false),
+	  ringing(false),
+	  numericresponse(false),
+	  // Default to direct null modem connection; Telnet mode interprets IAC codes
+	  telnetmode(false),
+	  connected(false),
+	  doresponse(0),
+	  waiting_tx_character(0),
+	  cmdpause(0),
+	  ringtimer(0),
+	  ringcount(0),
+	  plusinc(0),
+	  cmdpos(0),
+	  flowcontrol(0),
+	  tmpbuf {0},
+	  listenport(23),
+	  reg {0},
+	  serversocket(nullptr),
+	  clientsocket(nullptr),
+	  waitingclientsocket(nullptr),
+	  telClient {},
+	  dial {}
+{
 	InstallationSuccessful=false;
-	connected=false;
 
-	rqueue=new CFifo(MODEM_BUFFER_QUEUE_SIZE);
-	tqueue=new CFifo(MODEM_BUFFER_QUEUE_SIZE);
-	
-	// Default to direct null modem connection.  Telnet mode interprets IAC codes
-	telnetmode = false;
+	// Setup the listening port, and ignore the return code as this is optional
+	(void) getBituSubstring("listenport:", &listenport, cmd);
 
-	// Initialize the sockets and setup the listening port
-	listenport = 23;
-	waitingclientsocket=0;
-	clientsocket = 0;
-	serversocket = 0;
-	getBituSubstring("listenport:", &listenport, cmd);
-	
 	// TODO: Fix dialtones if requested
 	//mhd.chan=MIXER_AddChannel((MIXER_MixHandler)this->MODEM_CallBack,8000,"MODEM");
 	//MIXER_Enable(mhd.chan,false);
 	//MIXER_SetMode(mhd.chan,MIXER_16MONO);
-		
+
 	CSerial::Init_Registers();
 	Reset(); // reset calls EnterIdleState
-		
+
 	setEvent(SERIAL_POLLING_EVENT,1);
 	InstallationSuccessful=true;
 }
 
 CSerialModem::~CSerialModem() {
-	if(serversocket) delete serversocket;
-	if(clientsocket) delete clientsocket;
-	if(waitingclientsocket) delete waitingclientsocket;
-
-	delete rqueue;
-	delete tqueue;
-
 	// remove events
-	for(Bitu i = SERIAL_BASE_EVENT_COUNT+1;	i <= SERIAL_MODEM_EVENT_COUNT; i++)
+	for (Bitu i = SERIAL_BASE_EVENT_COUNT+1; i <= SERIAL_MODEM_EVENT_COUNT; i++)
 		removeEvent(i);
 }
 
@@ -79,8 +86,8 @@ void CSerialModem::handleUpperEvent(Bit16u type) {
 	switch (type) {
 	case SERIAL_RX_EVENT: {
 		// check for bytes to be sent to port
-		if(CSerial::CanReceiveByte())
-			if(rqueue->inuse() && (CSerial::getRTS()||(flowcontrol!=3))) {
+		if (CSerial::CanReceiveByte())
+			if (rqueue->inuse() && (CSerial::getRTS() || (flowcontrol != 3))) {
 				Bit8u rbyte = rqueue->getb();
 				//LOG_MSG("Modem: sending byte %2x back to UART3",rbyte);
 				CSerial::receiveByte(rbyte);
@@ -96,7 +103,7 @@ void CSerialModem::handleUpperEvent(Bit16u type) {
 			}
 		} else {
 			static Bits lcount=0;
-			if (lcount<1000) {
+			if (lcount < 1000) {
 				lcount++;
 				LOG_MSG("MODEM: TX Buffer overflow!");
 			}
@@ -123,7 +130,7 @@ void CSerialModem::handleUpperEvent(Bit16u type) {
 void CSerialModem::SendLine(const char *line) {
 	rqueue->addb(0xd);
 	rqueue->addb(0xa);
-	rqueue->adds((Bit8u *)line,strlen(line));
+	rqueue->adds((Bit8u *)line, strlen(line));
 	rqueue->addb(0xd);
 	rqueue->addb(0xa);
 }
@@ -132,18 +139,18 @@ void CSerialModem::SendLine(const char *line) {
 void CSerialModem::SendNumber(Bitu val) {
 	rqueue->addb(0xd);
 	rqueue->addb(0xa);
-	
-	rqueue->addb(val/100+'0');
+
+	rqueue->addb(val / 100 + '0');
 	val = val%100;
-	rqueue->addb(val/10+'0');
+	rqueue->addb(val / 10 + '0');
 	val = val%10;
-	rqueue->addb(val+'0');
+	rqueue->addb(val + '0');
 
 	rqueue->addb(0xd);
 	rqueue->addb(0xa);
 }
 
-void CSerialModem::SendRes(ResTypes response) {
+void CSerialModem::SendRes(const ResTypes response) {
 	char const * string = nullptr;
 	Bitu code = -1;
 	switch (response) {
@@ -159,10 +166,10 @@ void CSerialModem::SendRes(ResTypes response) {
 	}
 
 	if(doresponse != 1) {
-		if(doresponse == 2 && (response == ResRING ||
+		if (doresponse == 2 && (response == ResRING ||
 			response == ResCONNECT || response == ResNOCARRIER))
 			return;
-		if(numericresponse && code != static_cast<Bitu>(-1))
+		if (numericresponse && code != static_cast<Bitu>(-1))
 			SendNumber(code);
 		else if (string != nullptr)
 			SendLine(string);
@@ -184,18 +191,19 @@ bool CSerialModem::Dial(char * host) {
 
 	// Scan host for port
 	Bit16u port;
-	char * hasport=strrchr(host,':');
+	char * hasport = strrchr(host,':');
 	if (hasport) {
-		*hasport++=0;
-		port=(Bit16u)atoi(hasport);
+		*hasport++ = 0;
+		port = (Bit16u)atoi(hasport);
 	}
-	else port=MODEM_DEFAULT_PORT;
+	else
+		port = MODEM_DEFAULT_PORT;
+
 	// Resolve host we're gonna dial
 	LOG_MSG("Connecting to host %s port %u", host, port);
-	clientsocket = new TCPClientSocket(host, port);
-	if(!clientsocket->isopen) {
-		delete clientsocket;
-		clientsocket=0;
+	clientsocket.reset(new TCPClientSocket(host, port));
+	if (!clientsocket->isopen) {
+		clientsocket.reset(nullptr);
 		LOG_MSG("Failed to connect.");
 		SendRes(ResNOCARRIER);
 		EnterIdleState();
@@ -207,28 +215,28 @@ bool CSerialModem::Dial(char * host) {
 }
 
 void CSerialModem::AcceptIncomingCall(void) {
-	if(waitingclientsocket) {
-		clientsocket=waitingclientsocket;
-		waitingclientsocket=0;
+	if (waitingclientsocket) {
+		clientsocket = std::move(waitingclientsocket);
 		EnterConnectedState();
 	} else {
 		EnterIdleState();
 	}
 }
 
-Bitu CSerialModem::ScanNumber(char * & scan) {
+Bitu CSerialModem::ScanNumber(char * & scan) const {
 	Bitu ret=0;
-	while (char c=*scan) {
-		if (c>='0' && c<='9') {
+	while (char c = *scan) {
+		if (c >= '0' && c <= '9') {
 			ret*=10;
 			ret+=c-'0';
 			scan++;
-		} else break;
+		} else
+			break;
 	}
 	return ret;
 }
 
-char CSerialModem::GetChar(char * & scan) {
+char CSerialModem::GetChar(char * & scan) const {
 	char ch = *scan;
 	scan++;
 	return ch;
@@ -237,23 +245,21 @@ char CSerialModem::GetChar(char * & scan) {
 void CSerialModem::Reset(){
 	EnterIdleState();
 	cmdpos = 0;
-	cmdbuf[0]=0;
+	cmdbuf[0] = 0;
 	oldDTRstate = getDTR();
 	flowcontrol = 0;
 	plusinc = 0;
-	if(clientsocket) {
-		delete clientsocket;
-		clientsocket=0;
-	}
-	memset(&reg,0,sizeof(reg));
-	reg[MREG_AUTOANSWER_COUNT]=0;	// no autoanswer
-	reg[MREG_RING_COUNT] = 1;
-	reg[MREG_ESCAPE_CHAR]='+';
-	reg[MREG_CR_CHAR]='\r';
-	reg[MREG_LF_CHAR]='\n';
-	reg[MREG_BACKSPACE_CHAR]='\b';
+	clientsocket.reset(nullptr);
 
-	cmdpause = 0;	
+	memset(&reg,0,sizeof(reg));
+	reg[MREG_AUTOANSWER_COUNT] = 0;  // no autoanswer
+	reg[MREG_RING_COUNT]       = 1;
+	reg[MREG_ESCAPE_CHAR]      = '+';
+	reg[MREG_CR_CHAR]          = '\r';
+	reg[MREG_LF_CHAR]          = '\n';
+	reg[MREG_BACKSPACE_CHAR]   = '\b';
+
+	cmdpause = 0;
 	echo = true;
 	doresponse = 0;
 	numericresponse = false;
@@ -263,37 +269,32 @@ void CSerialModem::Reset(){
 }
 
 void CSerialModem::EnterIdleState(void){
-	connected=false;
-	ringing=false;
+	connected = false;
+	ringing = false;
+	clientsocket.reset(nullptr);
+	waitingclientsocket.reset(nullptr);
 
-	if(clientsocket) {
-		delete clientsocket;
-		clientsocket=0;
-	}
-
-	if(waitingclientsocket) {	// clear current incoming socket
-		delete waitingclientsocket;
-		waitingclientsocket=0;
-	}
 	// get rid of everything
-	if(serversocket) {
-		while( (waitingclientsocket=serversocket->Accept()) )
-			delete waitingclientsocket;
+	if (serversocket) {
+		waitingclientsocket.reset(serversocket->Accept());
+		while (waitingclientsocket) {
+			waitingclientsocket.reset(serversocket->Accept());
+		}
 	} else if (listenport) {
 
-		serversocket=new TCPServerSocket(listenport);
-		if(!serversocket->isopen) {
-			LOG_MSG("Serial%u: Modem could not open TCP port %u.",
-			        static_cast<uint32_t>(COMNUMBER),
-			        static_cast<uint32_t>(listenport));
-			delete serversocket;
-			serversocket=0;
+		serversocket.reset(new TCPServerSocket(listenport));
+		if (!serversocket->isopen) {
+			LOG_MSG("Serial%" PRIuPTR ": Modem could not open TCP port %" PRIuPTR ".",
+			        COMNUMBER,
+			        listenport);
+
+			serversocket.reset(nullptr);
 		} else
-			LOG_MSG("Serial%u: Modem listening on port %u...",
-		            static_cast<uint32_t>(COMNUMBER),
-			        static_cast<uint32_t>(listenport));
+			LOG_MSG("Serial%" PRIuPTR ": Modem listening on port %" PRIuPTR "...",
+			        COMNUMBER,
+			        listenport);
 	}
-	waitingclientsocket=0;
+	waitingclientsocket.reset(nullptr);
 
 	commandmode = true;
 	CSerial::setCD(false);
@@ -304,11 +305,8 @@ void CSerialModem::EnterIdleState(void){
 }
 
 void CSerialModem::EnterConnectedState(void) {
-	if(serversocket) {
-		// we don't accept further calls
-		delete serversocket;
-		serversocket=0;
-	}
+	// we don't accept further calls
+	serversocket.reset(nullptr);
 	SendRes(ResCONNECT);
 	commandmode = false;
 	memset(&telClient, 0, sizeof(telClient));
@@ -325,7 +323,7 @@ void CSerialModem::DoCommand() {
 	LOG_MSG("Command sent to modem: ->%s<-\n", cmdbuf);
 	/* Check for empty line, stops dialing and autoanswer */
 	if (!cmdbuf[0]) {
-		reg[0]=0;	// autoanswer off
+		reg[0] = 0;	// autoanswer off
 		return;
 	}
 	//else {
@@ -357,21 +355,24 @@ void CSerialModem::DoCommand() {
 		char chr = GetChar(scanbuf);
 		switch (chr) {
 		case 'D': { // Dial
-			char * foundstr=&scanbuf[0];
-			if (*foundstr=='T' || *foundstr=='P') foundstr++;
+			char * foundstr = &scanbuf[0];
+			if (*foundstr == 'T' || *foundstr == 'P')
+				foundstr++;
+
 			// Small protection against empty line and long string
-			if ((!foundstr[0]) || (strlen(foundstr)>100)) {
+			if ((!foundstr[0]) || (strlen(foundstr) > 100)) {
 				SendRes(ResERROR);
 				return;
 			}
-			char* helper;
 			// scan for and remove spaces; weird bug: with leading spaces in the string,
 			// SDLNet_ResolveHost will return no error but not work anyway (win)
-			while(foundstr[0]==' ') foundstr++;
-			helper=foundstr;
+			while(foundstr[0] == ' ')
+				foundstr++;
+
+			char* helper = foundstr;
 			helper+=strlen(foundstr);
-			while(helper[0]==' ') {
-				helper[0]=0;
+			while(helper[0] == ' ') {
+				helper[0] = 0;
 				helper--;
 			}
 
@@ -383,7 +384,8 @@ void CSerialModem::DoCommand() {
 				bool isNum = true;
 				size_t fl = strlen(foundstr);
 				for (size_t i = 0; i < fl; i++)
-					if (foundstr[i] < '0' || foundstr[i] > '9') isNum = false;
+					if (foundstr[i] < '0' || foundstr[i] > '9')
+						isNum = false;
 				if (isNum) {
 					// Parameter is a number with at least 12 digits => this cannot
 					// be a valid IP/name
@@ -397,7 +399,7 @@ void CSerialModem::DoCommand() {
 							buffer[j++] = '.';
 						// If the string is longer than 12 digits,
 						// interpret the rest as port
-						if (i == 11 && strlen(foundstr)>12)
+						if (i == 11 && strlen(foundstr) > 12)
 							buffer[j++] = ':';
 					}
 					buffer[j] = 0;
@@ -479,7 +481,8 @@ void CSerialModem::DoCommand() {
 		case 'Z': { // Reset and load profiles
 			// scan the number away, if any
 			ScanNumber(scanbuf);
-			if (clientsocket) SendRes(ResNOCARRIER);
+			if (clientsocket)
+				SendRes(ResNOCARRIER);
 			Reset();
 			break;
 		}
@@ -489,32 +492,34 @@ void CSerialModem::DoCommand() {
 			// Response options
 			// 0 = all on, 1 = all off,
 			// 2 = no ring and no connect/carrier in answermode
-			Bitu val = ScanNumber(scanbuf);	
-			if(!(val>2)) {
-				doresponse=val;
+			Bitu val = ScanNumber(scanbuf);
+			if (!(val > 2)) {
+				doresponse = val;
 				break;
 			} else {
 				SendRes(ResERROR);
 				return;
 			}
 		}
-		case 'S': { // Registers	
-			Bitu index=ScanNumber(scanbuf);
-			if(index>=SREGS) {
+		case 'S': { // Registers
+			Bitu index = ScanNumber(scanbuf);
+			if (index >= SREGS) {
 				SendRes(ResERROR);
 				return; //goto ret_none;
 			}
-			
-			while(scanbuf[0]==' ') scanbuf++;	// skip spaces
-			
-			if(scanbuf[0]=='=') {	// set register
+
+			while (scanbuf[0] == ' ')
+				scanbuf++; // skip spaces
+
+			if (scanbuf[0] == '=') { // set register
 				scanbuf++;
-				while(scanbuf[0]==' ') scanbuf++;	// skip spaces
+				while (scanbuf[0] == ' ')
+					scanbuf++; // skip spaces
 				Bitu val = ScanNumber(scanbuf);
-				reg[index]=val;
+				reg[index] = val;
 				break;
 			}
-			else if(scanbuf[0]=='?') {	// get register
+			else if (scanbuf[0] == '?') { // get register
 				SendNumber(reg[index]);
 				scanbuf++;
 				break;
@@ -527,7 +532,8 @@ void CSerialModem::DoCommand() {
 			switch(cmdchar) {
 				case 'K': {
 					Bitu val = ScanNumber(scanbuf);
-					if(val<5) flowcontrol=val;
+					if(val < 5)
+						flowcontrol = val;
 					else {
 						SendRes(ResERROR);
 						return;
@@ -539,16 +545,16 @@ void CSerialModem::DoCommand() {
 					SendRes(ResERROR);
 					return;
 				default:
-					LOG_MSG("Modem: Unhandled command: &%c%u",
+					LOG_MSG("Modem: Unhandled command: &%c%" PRIuPTR,
 					        cmdchar,
-					        static_cast<uint32_t>(ScanNumber(scanbuf)));
+					        ScanNumber(scanbuf));
 					break;
 			}
 			break;
 		}
 		case '\\': { // \ escaped commands
 			char cmdchar = GetChar(scanbuf);
-			switch(cmdchar) {
+			switch (cmdchar) {
 				case 'N':
 					// error correction stuff - not emulated
 					if (ScanNumber(scanbuf) > 5) {
@@ -561,9 +567,9 @@ void CSerialModem::DoCommand() {
 					SendRes(ResERROR);
 					return;
 				default:
-					LOG_MSG("Modem: Unhandled command: \\%c%u",
+					LOG_MSG("Modem: Unhandled command: \\%c%" PRIuPTR,
 					        cmdchar,
-					        static_cast<uint32_t>(ScanNumber(scanbuf)));
+					        ScanNumber(scanbuf));
 					break;
 			}
 			break;
@@ -572,9 +578,9 @@ void CSerialModem::DoCommand() {
 			SendRes(ResOK);
 			return;
 		default:
-			LOG_MSG("Modem: Unhandled command: %c%u",
+			LOG_MSG("Modem: Unhandled command: %c%" PRIuPTR,
 			        chr,
-			        static_cast<uint32_t>(ScanNumber(scanbuf)));
+			        ScanNumber(scanbuf));
 			break;
 		}
 	}
@@ -583,44 +589,44 @@ void CSerialModem::DoCommand() {
 void CSerialModem::TelnetEmulation(Bit8u * data, Bitu size) {
 	Bitu i;
 	Bit8u c;
-	for(i=0;i<size;i++) {
+	for (i=0; i < size; i++) {
 		c = data[i];
-		if(telClient.inIAC) {
-			if(telClient.recCommand) {
-				if((c != 0) && (c != 1) && (c != 3)) {
+		if (telClient.inIAC) {
+			if (telClient.recCommand) {
+				if ((c != 0) && (c != 1) && (c != 3)) {
 					LOG_MSG("MODEM: Unrecognized option %u", c);
-					if(telClient.command>250) {
+					if (telClient.command > 250) {
 						/* Reject anything we don't recognize */
 						tqueue->addb(0xff);
 						tqueue->addb(252);
 						tqueue->addb(c); /* We won't do crap! */
 					}
 			}
-			switch(telClient.command) {
+			switch (telClient.command) {
 				case 251: /* Will */
-					if(c == 0) telClient.binary[TEL_SERVER] = true;
-					if(c == 1) telClient.echo[TEL_SERVER] = true;
-					if(c == 3) telClient.supressGA[TEL_SERVER] = true;
+					if (c == 0) telClient.binary[TEL_SERVER] = true;
+					if (c == 1) telClient.echo[TEL_SERVER] = true;
+					if (c == 3) telClient.supressGA[TEL_SERVER] = true;
 					break;
 				case 252: /* Won't */
-					if(c == 0) telClient.binary[TEL_SERVER] = false;
-					if(c == 1) telClient.echo[TEL_SERVER] = false;
-					if(c == 3) telClient.supressGA[TEL_SERVER] = false;
+					if (c == 0) telClient.binary[TEL_SERVER] = false;
+					if (c == 1) telClient.echo[TEL_SERVER] = false;
+					if (c == 3) telClient.supressGA[TEL_SERVER] = false;
 					break;
 				case 253: /* Do */
-					if(c == 0) {
+					if (c == 0) {
 						telClient.binary[TEL_CLIENT] = true;
 							tqueue->addb(0xff);
 							tqueue->addb(251);
 							tqueue->addb(0); /* Will do binary transfer */
 					}
-					if(c == 1) {
+					if (c == 1) {
 						telClient.echo[TEL_CLIENT] = false;
 							tqueue->addb(0xff);
 							tqueue->addb(252);
 							tqueue->addb(1); /* Won't echo (too lazy) */
 					}
-					if(c == 3) {
+					if (c == 3) {
 						telClient.supressGA[TEL_CLIENT] = true;
 							tqueue->addb(0xff);
 							tqueue->addb(251);
@@ -628,19 +634,19 @@ void CSerialModem::TelnetEmulation(Bit8u * data, Bitu size) {
 					}
 					break;
 				case 254: /* Don't */
-					if(c == 0) {
+					if (c == 0) {
 						telClient.binary[TEL_CLIENT] = false;
 							tqueue->addb(0xff);
 							tqueue->addb(252);
 							tqueue->addb(0); /* Won't do binary transfer */
 					}
-					if(c == 1) {
+					if (c == 1) {
 						telClient.echo[TEL_CLIENT] = false;
 							tqueue->addb(0xff);
 							tqueue->addb(252);
 							tqueue->addb(1); /* Won't echo (fine by me) */
 					}
-					if(c == 3) {
+					if (c == 3) {
 						telClient.supressGA[TEL_CLIENT] = true;
 							tqueue->addb(0xff);
 							tqueue->addb(251);
@@ -655,15 +661,15 @@ void CSerialModem::TelnetEmulation(Bit8u * data, Bitu size) {
 			telClient.recCommand = false;
 			continue;
 		} else {
-			if(c==249) {
+			if (c == 249) {
 				/* Go Ahead received */
 				telClient.inIAC = false;
 				continue;
 			}
 			telClient.command = c;
 			telClient.recCommand = true;
-			
-			if((telClient.binary[TEL_SERVER]) && (c == 0xff)) {
+
+			if ((telClient.binary[TEL_SERVER]) && (c == 0xff)) {
 				/* Binary data with value of 255 */
 				telClient.inIAC = false;
 				telClient.recCommand = false;
@@ -672,7 +678,7 @@ void CSerialModem::TelnetEmulation(Bit8u * data, Bitu size) {
 			}
 		}
 	} else {
-		if(c == 0xff) {
+		if (c == 0xff) {
 			telClient.inIAC = true;
 			continue;
 		}
@@ -691,7 +697,7 @@ void CSerialModem::Timer2(void) {
 	// Check for eventual break command
 	if (!commandmode) cmdpause++;
 	// Handle incoming data from serial port, read as much as available
-	CSerial::setCTS(true);	// buffer will get 'emptier', new data can be received 
+	CSerial::setCTS(true);	// buffer will get 'emptier', new data can be received
 	while (tqueue->inuse()) {
 		txval = tqueue->getb();
 		if (commandmode) {
@@ -699,9 +705,9 @@ void CSerialModem::Timer2(void) {
 				rqueue->addb(txval);
 				//LOG_MSG("Echo back to queue: %x",txval);
 			}
-			if (txval==0xa) continue;		//Real modem doesn't seem to skip this?
-			else if (txval==0x8 && (cmdpos > 0)) --cmdpos;	// backspace
-			else if (txval==0xd) DoCommand();				// return
+			if (txval == 0xa) continue; //Real modem doesn't seem to skip this?
+			else if (txval == 0x8 && (cmdpos > 0)) --cmdpos; // backspace
+			else if (txval == 0xd) DoCommand(); // return
 			else if (txval != '+') {
 				if(cmdpos<99) {
 					cmdbuf[cmdpos] = txval;
@@ -712,10 +718,10 @@ void CSerialModem::Timer2(void) {
 		else {// + character
 			// 1000 ticks have passed, can check for pause command
 			if (cmdpause > 1000) {
-				if(txval ==reg[MREG_ESCAPE_CHAR]) // +
+				if (txval == reg[MREG_ESCAPE_CHAR]) // +
 				{
 					plusinc++;
-					if(plusinc>=3) {
+					if (plusinc >= 3) {
 						LOG_MSG("Modem: Entering command mode(escape sequence)");
 						commandmode = true;
 						SendRes(ResOK);
@@ -725,55 +731,58 @@ void CSerialModem::Timer2(void) {
 				} else {
 					plusinc=0;
 				}
-	// If not a special pause command, should go for bigger blocks to send 
+	// If not a special pause command, should go for bigger blocks to send
 			}
 			tmpbuf[txbuffersize] = txval;
 			txbuffersize++;
 		}
 	} // while loop
-	
+
 	if (clientsocket && sendbyte && txbuffersize) {
 		// down here it saves a lot of network traffic
-		if(!clientsocket->SendArray(tmpbuf,txbuffersize)) {
+		if (!clientsocket->SendArray(tmpbuf,txbuffersize)) {
 			SendRes(ResNOCARRIER);
 			EnterIdleState();
 		}
 	}
 	// Handle incoming to the serial port
-	if(!commandmode && clientsocket && rqueue->left()) {
+	if (!commandmode && clientsocket && rqueue->left()) {
 		usesize = rqueue->left();
-		if (usesize>16) usesize=16;
-		if(!clientsocket->ReceiveArray(tmpbuf, &usesize)) {
+		if (usesize > 16)
+			usesize = 16;
+		if (!clientsocket->ReceiveArray(tmpbuf, &usesize)) {
 			SendRes(ResNOCARRIER);
 			EnterIdleState();
-		} else if(usesize) {
-			// Filter telnet commands 
-			if(telnetmode) TelnetEmulation(tmpbuf, usesize);
-			else rqueue->adds(tmpbuf,usesize);
+		} else if (usesize) {
+			// Filter telnet commands
+			if (telnetmode)
+				TelnetEmulation(tmpbuf, usesize);
+			else
+				rqueue->adds(tmpbuf,usesize);
 			cmdpause = 0;
-		} 
+		}
 	}
 	// Check for incoming calls
 	if (!connected && !waitingclientsocket && serversocket) {
-		waitingclientsocket=serversocket->Accept();
-		if(waitingclientsocket) {	
-			if(!CSerial::getDTR()) {
+		waitingclientsocket.reset(serversocket->Accept());
+		if (waitingclientsocket) {
+			if (!CSerial::getDTR()) {
 				// accept no calls with DTR off; TODO: AT &Dn
 				EnterIdleState();
 			} else {
-				ringing=true;
+				ringing = true;
 				SendRes(ResRING);
 				CSerial::setRI(!CSerial::getRI());
 				//MIXER_Enable(mhd.chan,true);
 				ringtimer = 3000;
-				reg[1] = 0;		//Reset ring counter reg
+				reg[1] = 0; //Reset ring counter reg
 			}
 		}
 	}
 	if (ringing) {
 		if (ringtimer <= 0) {
 			reg[1]++;
-			if ((reg[0]>0) && (reg[0]>=reg[1])) {
+			if ((reg[0] > 0) && (reg[0] >= reg[1])) {
 				AcceptIncomingCall();
 				return;
 			}
@@ -791,7 +800,7 @@ void CSerialModem::Timer2(void) {
 //TODO
 void CSerialModem::RXBufferEmpty() {
 	// see if rqueue has some more bytes
-	if(rqueue->inuse() && (CSerial::getRTS()||(flowcontrol!=3))){
+	if (rqueue->inuse() && (CSerial::getRTS() || (flowcontrol != 3))){
 		Bit8u rbyte = rqueue->getb();
 		//LOG_MSG("Modem: sending byte %2x back to UART1",rbyte);
 		CSerial::receiveByte(rbyte);
@@ -799,14 +808,15 @@ void CSerialModem::RXBufferEmpty() {
 }
 
 void CSerialModem::transmitByte(Bit8u val, bool first) {
-	waiting_tx_character=val;
+	waiting_tx_character = val;
 	setEvent(MODEM_TX_EVENT, bytetime); // TX event
-	if(first) ByteTransmitting();
+	if (first)
+		ByteTransmitting();
 	//LOG_MSG("MODEM: Byte %x to be transmitted",val);
 }
 
 void CSerialModem::updatePortConfig(Bit16u, Bit8u lcr) {
-	(void) lcr; // deliberately unused by needed to meet the API
+	(void) lcr; // deliberately unused but needed for API compliance
 }
 
 void CSerialModem::updateMSR() {
@@ -818,26 +828,26 @@ void CSerialModem::setBreak(bool) {
 }
 
 void CSerialModem::setRTSDTR(bool rts_, bool dtr_) {
-	(void) rts_; // deliberately unused but needed to meet the API
+	(void) rts_; // deliberately unused but needed for API compliance
 	setDTR(dtr_);
 }
 void CSerialModem::setRTS(bool val) {
-	(void) val; // deliberately unused but needed to meet the API
+	(void) val; // deliberately unused but but needed for API compliance
 }
 void CSerialModem::setDTR(bool val) {
-	if(!val && connected) {
+	if (!val && connected) {
 		// If DTR goes low, hang up.
 		SendRes(ResNOCARRIER);
 		EnterIdleState();
 		LOG_MSG("Modem: Hang up due to dropped DTR.");
-	}	
+	}
 }
 /*
 void CSerialModem::updateModemControlLines() {
 	//bool txrdy=tqueue->left();
 	//if(CSerial::getRTS() && txrdy) CSerial::setCTS(true);
 	//else CSerial::setCTS(tqueue->left());
-	
+
 	// If DTR goes low, hang up.
 	if(connected)
 		if(oldDTRstate)
@@ -852,4 +862,3 @@ void CSerialModem::updateModemControlLines() {
 */
 
 #endif
-
diff --git a/src/hardware/serialport/softmodem.h b/src/hardware/serialport/softmodem.h
index 9f6376aa..c3e01d61 100644
--- a/src/hardware/serialport/softmodem.h
+++ b/src/hardware/serialport/softmodem.h
@@ -20,6 +20,9 @@
 #ifndef DOSBOX_SERIALMODEM_H
 #define DOSBOX_SERIALMODEM_H
 
+#include <vector>
+#include <memory>
+
 #include "dosbox.h"
 #if C_MODEM
 #include "serialport.h"
@@ -56,96 +59,105 @@ enum ResTypes {
 
 class CFifo {
 public:
-	CFifo(Bitu _size) {
-		size=_size;
-		pos=used=0;
-		data=new Bit8u[size];
+	CFifo(Bitu _size)
+		: data(_size),
+		  size(_size),
+		  pos(0),
+		  used(0)
+	{}
+
+	INLINE Bitu left(void) const {
+		return size - used;
 	}
-	~CFifo() {
-		delete[] data;
-	}
-	INLINE Bitu left(void) {
-		return size-used;
-	}
-	INLINE Bitu inuse(void) {
+	INLINE Bitu inuse(void) const {
 		return used;
 	}
 	void clear(void) {
-		used=pos=0;
+		used = 0;
+		pos = 0;
 	}
 
 	void addb(Bit8u _val) {
-		if(used>=size) {
-			static Bits lcount=0;
-			if (lcount<1000) {
+		if(used >= size) {
+			static Bits lcount = 0;
+			if (lcount < 1000) {
 				lcount++;
 				LOG_MSG("MODEM: FIFO Overflow! (addb)");
 			}
 			return;
 		}
 		//assert(used<size);
-		Bitu where=pos+used;
-		if (where>=size) where-=size;
+		Bitu where = pos + used;
+		if (where >= size)
+			where -= size;
 		data[where]=_val;
 		//LOG_MSG("+%x",_val);
 		used++;
 	}
+
 	void adds(Bit8u * _str,Bitu _len) {
-		if((used+_len)>size) {
+		if ( (used+_len) > size) {
 			static Bits lcount=0;
-			if (lcount<1000) {
+			if (lcount < 1000) {
 				lcount++;
-				LOG_MSG("MODEM: FIFO Overflow! (adds len %u)",
-				        static_cast<uint32_t>(_len));
+				LOG_MSG("MODEM: FIFO Overflow! (adds len %" PRIuPTR ")",
+				        _len);
 			}
 			return;
 		}
-		
+
 		//assert((used+_len)<=size);
-		Bitu where=pos+used;
-		used+=_len;
+		Bitu where = pos + used;
+		used += _len;
 		while (_len--) {
-			if (where>=size) where-=size;
+			if (where >= size)
+				where -= size;
 			//LOG_MSG("+'%x'",*_str);
-			data[where++]=*_str++;
+			data[where++] = *_str++;
 		}
 	}
+
 	Bit8u getb(void) {
 		if (!used) {
-			static Bits lcount=0;
-			if (lcount<1000) {
+			static Bits lcount = 0;
+			if (lcount < 1000) {
 				lcount++;
 				LOG_MSG("MODEM: FIFO UNDERFLOW! (getb)");
 			}
 			return data[pos];
 		}
-			Bitu where=pos;
-		if (++pos>=size) pos-=size;
+		Bitu where = pos;
+		if (++pos >= size)
+			pos -= size;
 		used--;
 		//LOG_MSG("-%x",data[where]);
 		return data[where];
 	}
+
 	void gets(Bit8u * _str,Bitu _len) {
 		if (!used) {
-			static Bits lcount=0;
-			if (lcount<1000) {
+			static Bits lcount = 0;
+			if (lcount < 1000) {
 				lcount++;
-				LOG_MSG("MODEM: FIFO UNDERFLOW! (gets len %u)",
-				        static_cast<uint32_t>(_len));
+				LOG_MSG("MODEM: FIFO UNDERFLOW! (gets len %" PRIuPTR ")",
+				        _len);
 			}
 			return;
 		}
 			//assert(used>=_len);
-		used-=_len;
+		used -= _len;
 		while (_len--) {
 			//LOG_MSG("-%x",data[pos]);
-			*_str++=data[pos];
-			if (++pos>=size) pos-=size;
+			*_str++ = data[pos];
+			if (++pos >= size)
+				pos -= size;
 		}
 	}
 private:
-	Bit8u * data;
-	Bitu size,pos,used;
+	std::vector<Bit8u> data;
+	Bitu size;
+	Bitu pos;
+	Bitu used;
 };
 #define MREG_AUTOANSWER_COUNT 0
 #define MREG_RING_COUNT 1
@@ -157,17 +169,12 @@ private:
 
 class CSerialModem : public CSerial {
 public:
-
-	CFifo *rqueue;
-	CFifo *tqueue;
-
 	CSerialModem(Bitu id, CommandLine* cmd);
 	~CSerialModem();
-
 	void Reset();
 
 	void SendLine(const char *line);
-	void SendRes(ResTypes response);
+	void SendRes(const ResTypes response);
 	void SendNumber(Bitu val);
 
 	void EnterIdleState();
@@ -176,12 +183,12 @@ public:
 	void openConnection(void);
 	bool Dial(char * host);
 	void AcceptIncomingCall(void);
-	Bitu ScanNumber(char * & scan);
-	char GetChar(char * & scan);
+	Bitu ScanNumber(char * & scan) const;
+	char GetChar(char * & scan) const;
 
 	void DoCommand();
-	
-	void MC_Changed(Bitu new_mc);
+
+	// void MC_Changed(Bitu new_mc);
 
 	void TelnetEmulation(Bit8u * data, Bitu size);
 
@@ -201,50 +208,44 @@ public:
 	void setRTS(bool val);
 	void setDTR(bool val);
 
+	std::unique_ptr<CFifo> rqueue;
+	std::unique_ptr<CFifo> tqueue;
+
 protected:
 	char cmdbuf[255];
-	bool commandmode;		// true: interpret input as commands
-	bool echo;				// local echo on or off
-
+	bool commandmode;       // true: interpret input as commands
+	bool echo;              // local echo on or off
 	bool oldDTRstate;
 	bool ringing;
-	//bool response;
-	bool numericresponse;	// true: send control response as number.
-							// false: send text (i.e. NO DIALTONE)
-	bool telnetmode;		// true: process IAC commands.
-	
+	bool numericresponse;   // true: send control response as number.
+	                        // false: send text (i.e. NO DIALTONE)
+	bool telnetmode;        // true: process IAC commands.
 	bool connected;
 	Bitu doresponse;
-
 	Bit8u waiting_tx_character;
-
 	Bitu cmdpause;
 	Bits ringtimer;
 	Bits ringcount;
 	Bitu plusinc;
 	Bitu cmdpos;
 	Bitu flowcontrol;
-
 	Bit8u tmpbuf[MODEM_BUFFER_QUEUE_SIZE];
-
 	Bitu listenport;
 	Bit8u reg[SREGS];
-	
-	
-	TCPServerSocket* serversocket;
-	TCPClientSocket* clientsocket;
-	TCPClientSocket* waitingclientsocket;
+	std::unique_ptr<TCPServerSocket> serversocket;
+	std::unique_ptr<TCPClientSocket> clientsocket;
+	std::unique_ptr<TCPClientSocket> waitingclientsocket;
 
 	struct {
 		bool binary[2];
 		bool echo[2];
 		bool supressGA[2];
 		bool timingMark[2];
-					
 		bool inIAC;
 		bool recCommand;
 		Bit8u command;
 	} telClient;
+
 	struct {
 		bool active;
 		double f1, f2;
@@ -253,4 +254,4 @@ protected:
 	} dial;
 };
 #endif
-#endif 
+#endif