string MachineParser::encode(Instruction i)
// Given a valid instruction, returns a string representing the 32 bit MIPS binary encoding
// of that instruction.
{
OpcodeTable* myTable = new OpcodeTable;
Opcode myOpcode = i.getOpcode();
string ASMString = "";
//adds the opcode(alphabetical representation) of the instruction to the string
ASMString += (myTable-> getName(myOpcode) + " "); // we must find the name for each instruction
//FOR ITYPE INSTRUCTIONS
if(myTable -> getInstType(myOpcode) == ITYPE)
{
if(myTable -> IMMposition(myOpcode) == 1) //symbolizes a load store instruction since immediate is
//is at position 1
{
if( myTable -> RTposition(myOpcode) != -1) //if the RT register is being used
{
ASMString += i.getRT();
ASMString += ", ";
}
//convert the immediate to a string, the method deals with the two's complement conversion
ASMString+= decimalToString(i.getImmediate());
if( myTable -> RSposition(myOpcode) != -1)
{
ASMString += "("+i.getRS()+")"; //paranthesis for load instruction $register(offset)
}
}
else
//THIS IS FOR INSTRUCTIONS THAT ARE NOT LOAD OR STORE
{
if( myTable -> RSposition(myOpcode) >= 0)
{
ASMString += (i.getRS());
ASMString += ", ";
}
if( myTable -> RTposition(myOpcode) >= 0)
{
ASMString += i.getRT() ;
ASMString += ", ";
}
if((ASMString.find("beq")!=std::string::npos)) //meaning instruction is of type branch if equal to thus immediate is an addresss
{
ASMString += decimalToHex(i.getImmediate()); //converts the address to which we have to branch from decimal to hexadecimal
}
else //if its not a beq instruction then the immedaite is not an address so we simply parse it to a string
//instead of treating it as an address
{
ASMString += decimalToString(i.getImmediate());
}
}
}
//FOR RTYPE INSTRUCTIONS
else if(myTable -> getInstType(myOpcode) == RTYPE)
{
//I've put a series of conditional statements which using the opcode type to determine the fields that need to be added to
// ASM String
//we iterate through the number of elements in an instruction of type (myOpcode) and
//we find the RD, RS, RT as well as the immediate
for(int position = 0; position < myTable -> numOperands(myOpcode); position++)
{
if((myTable->RDposition(myOpcode)) == position)
{
ASMString += (i.getRD());
}
if(myTable-> IMMposition(myOpcode) == position)
{
ASMString += decimalToString(i.getImmediate());
}
if(myTable->RSposition(myOpcode) == position)
{
ASMString+=i.getRS();
}
if((myTable->RTposition(myOpcode)) == position)
{
ASMString += (i.getRT());
}
if(position < (myTable -> numOperands(myOpcode)-1)) // comma after every register
{
ASMString += ", ";
}
}
}
//FOR JTYPE INSTRUCTIONS
else
{
if(myTable -> isIMMLabel(myOpcode) == true) //J type instructions have immediate labels
{
ASMString += decimalToHex(i.getImmediate()); //convert the immedaite to its hexadeciaml representation
}
}
// cout <<"My decoded instructions are " <<ASMString << endl;
return ASMString;
}
int dealWithAConnection()
{
debug("ok: childProcess().start.");
close(pSession->localListener); // child doesn't need the listener
debug("ok: childProcess(). close(localListener).");
string tString;
int tTryTime = 0;
pSession->sessionClosed = 0;
pSession->userLogedIn = 0;
pSession->sCurrentPathForClient = "";
pSession->tryTimeMax = 3;
packSftpMessagePacket("+Sunny SFTP Service. Please send user-ID. Test ID: lab123.");
packTcpPacket();
while(1)//each loop for each command
{
pHandleSftpPacket->sExpectedPacketType = "commandPacket";
while(pSession->userLogedIn == 0)
{
debug("ok: checking user-ID.");
tTryTime ++;
unpackTcpPacket();// may set pSession->sessionClosed = 1
if(pSession->sessionClosed)
{
return 1;
}
unpackSftpPacket();
if(!pHandleSftpCommandPacket->sCmd.compare("USER"))
{
if(!pHandleSftpCommandPacket->sArgs.compare("lab123"))
{
pSession->userLogedIn = 1;
cout<<endl<<"ok: " + pHandleSftpCommandPacket->sArgs +" logged in."<<endl<<endl;
packSftpMessagePacket("!" + pHandleSftpCommandPacket->sArgs +" logged in.");
packTcpPacket();
break;
}
else
{
cout<<"ok: Invalid user-id, need try again."<<endl;
if(tTryTime >= pSession->tryTimeMax)
{
cout<<"ERR: Illegal access. A user tried " + decimalToString(tTryTime) + " times. Session will close."<<endl;
pSession->sessionClosed = 1;
close(pSession->localSocket);
debug("ok: child: close(localSocket).");
exit(1);
}
packSftpMessagePacket("-Invalid user-id, you have " + decimalToString(pSession->tryTimeMax-tTryTime) + " time(s) left to try.");
packTcpPacket();
}
}
else
{
cout<<"ok: Illegal command, need \"USER ID\"."<<endl;
if(tTryTime >= pSession->tryTimeMax)
{
cout<<"ERR: Illegal access. A user tried " + decimalToString(tTryTime) + " times. Session will close."<<endl;
pSession->sessionClosed = 1;
close(pSession->localSocket);
debug("ok: child: close(localSocket).");
exit(1);
}
packSftpMessagePacket("-Illegal command, please send \"USER ID\", you have " + decimalToString(pSession->tryTimeMax-tTryTime) + " time(s) left to try.");
packTcpPacket();
}
}
unpackTcpPacket();
pHandleSftpPacket->sExpectedPacketType = "commandPacket";
unpackSftpPacket();
pSession->commandTimer = clock();
if(!pHandleSftpCommandPacket->sCmd.compare("SEND") && pSession->readyForSubcommand)
{
debug("ok: switch cmd: SEND.start.");
sendTheRequestFile();
pSession->readyForSubcommand = 0;
debug("ok: switch cmd: SEND.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("STOP") && pSession->readyForSubcommand)
{
debug("ok: switch cmd: STOP.start.");
pSession->readyForSubcommand = 0;
debug("ok: switch cmd: STOP.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("STOR"))
{
debug("ok: switch cmd: STOR.start.");
if(pHandleSftpCommandPacket->sArgs.size() < 5)
{
printf("ERR: unexpected command:%s.\n",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: server received unexpected command");
packTcpPacket();
continue;
}
pHandleSftpCommandPacket->sArgFirst = pHandleSftpCommandPacket->sArgs.substr(0,3);
pHandleSftpCommandPacket->sArgFirst = toUpString(pHandleSftpCommandPacket->sArgFirst);
pHandleSftpCommandPacket->sArgSecond = pHandleSftpCommandPacket->sArgs.substr(4);
if(!pHandleSftpCommandPacket->sArgFirst.compare("NEW"))
{
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
openReadFile();
closeReadFile();
if(pAboutReadFile->sizeFile != -1)//file exists
{
pHandleSftpCommandPacket->sArgSecond = (timeStampString() + "_" + pHandleSftpCommandPacket->sArgSecond);
if(dbug)printf("ok: new filename:%s.\n",pHandleSftpCommandPacket->sArgSecond.c_str());
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
packSftpMessagePacket("+File exists, will create new generation of file.");
packTcpPacket();
pSession->readyForSubcommand = 1;
}
else//file not exists
{
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
packSftpMessagePacket("+File does not exist, will create new file.");
packTcpPacket();
pSession->readyForSubcommand = 1;
}
}
else if(!pHandleSftpCommandPacket->sArgFirst.compare("OLD"))
{
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
openReadFile();
closeReadFile();
if(pAboutReadFile->sizeFile != -1)//file exists
{
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
packSftpMessagePacket("+Will write over old file.");
packTcpPacket();
pSession->readyForSubcommand = 1;
}
else//file not exists
{
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
packSftpMessagePacket("+Will create new file.");
packTcpPacket();
pSession->readyForSubcommand = 1;
}
}
else if(!pHandleSftpCommandPacket->sArgFirst.compare("APP"))
{
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
openReadFile();
closeReadFile();
if(pAboutReadFile->sizeFile != -1)//file exists
{
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
packSftpMessagePacket("+Will append to file.");
packTcpPacket();
char aChar[] = "ab";
pAboutWriteFile->pOpenWriteType = aChar;//after transfer, set back to default //pAboutWriteFile->pOpenWriteType = aDefaultOpenWriteType
pSession->readyForSubcommand = 1;
}
else//file not exists
{
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
packSftpMessagePacket("+Will create file.");
packTcpPacket();
pSession->readyForSubcommand = 1;
}
}
else
{
printf("ERR: unexpected command:%s.\n",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: server received unexpected command.");
packTcpPacket();
continue;
}
debug("ok: switch cmd: STOR.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("SIZE") && pSession->readyForSubcommand)
{
debug("ok: switch cmd: SIZE.start.");
pAboutWriteFile->sizeFile = atoi(pHandleSftpCommandPacket->sArgs.c_str());
printf("ok: file size: %d bytes.\n",pAboutWriteFile->sizeFile);
int tInt;
if(pAboutWriteFile->sizeFile >= (tInt = pAboutWriteFile->sizeFreeDiskByte()) )
{
if(dbug)printf("ok: disk free size >= %d bytes.\n",tInt);
say("ERR: disk full.");
packSftpMessagePacket("-Not enough room, dont send it.");
packTcpPacket();
continue;
}
else//disk space is ok
{
if(dbug)printf("ok: disk free size > %d bytes.\n",tInt);
packSftpMessagePacket("+ok, waiting for file.");
packTcpPacket();
say("ok: ready to receive file.");
pHandleSftpPacket->sExpectedPacketType = "dataPacket";
if(receiveTheRequestFile())
{
packSftpMessagePacket("-Couldn't save.");
packTcpPacket();
say("ERR: couldn't save.");
continue;
}
else
{
packSftpMessagePacket("+Saved:"+pSession->sLocalFileAddress.substr(pSession->sCurrentPath.size()));
packTcpPacket();
cout<<"ok: saved:" + pSession->sLocalFileAddress<<endl;
}
}//if //else//disk space is ok
pSession->readyForSubcommand = 0;
pAboutWriteFile->pOpenWriteType = aDefaultOpenWriteType;//"wb"
debug("ok: switch cmd: SIZE.end.");
}//else if "SIZE"
else if(!pHandleSftpCommandPacket->sCmd.compare("RETR"))
{
debug("ok: switch cmd: RETR.start.");
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgs;
if(dbug)cout<<"ok: sFileAddress:"<<pSession->sLocalFileAddress<<endl;
if(openReadFile())
{
printf("ERR: file not exists:%s.\n",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: file not exists.");
packTcpPacket();
continue;
}
closeReadFile();
tString = decimalToString(pAboutReadFile->sizeFile);
packSftpMessagePacket(tString);
packTcpPacket();
pSession->readyForSubcommand = 1;
debug("ok: switch cmd: RETR.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("NAME"))
{
debug("ok: switch cmd: NAME.start.");
pSession->sLocalFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgs;
if(openReadFile())
{
printf("ERR: file not exists:%s.\n",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: file not exists.");
packTcpPacket();
continue;
}
closeReadFile();
packSftpMessagePacket("+File exists.");
packTcpPacket();
string tsOldName = pHandleSftpCommandPacket->sArgs;
unpackTcpPacket();
pHandleSftpPacket->sExpectedPacketType = "commandPacket";
unpackSftpPacket();
if(pHandleSftpCommandPacket->sCmd.compare("TOBE"))//if not "TOBE"
{
printf("ERR: unexpected command following \"NAME\":%s.",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: server received unexpected command following \"NAME\".");
packTcpPacket();
continue;
}
if(!openReadFile(pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgs))
{
printf("ERR: new filename exists:%s.\n",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: new filename exists.");
packTcpPacket();
closeReadFile();
continue;
}
if(rename( (pSession->sCurrentPath + pSession->sCurrentPathForClient + tsOldName).c_str(),
(pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgs).c_str()
))
{
printf("ERR: rename error, file may under using:%s.\n",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: rename error, file may under using.");
packTcpPacket();
continue;
}
packSftpMessagePacket("+" + tsOldName +" renamed to " + pHandleSftpCommandPacket->sArgs);
packTcpPacket();
debug("ok: switch cmd: NAME.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("KILL"))
{
debug("ok: switch cmd: KILL.start.");
if (remove((pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgs).c_str()))
{
printf("ERR: unexpected filename:%s.\n",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: server received unexpected filename.");
packTcpPacket();
continue;
}
cout<<"ok: file:" + pHandleSftpCommandPacket->sArgs + " deleted."<<endl;
packSftpMessagePacket("+" + pHandleSftpCommandPacket->sArgs + " deleted.");
packTcpPacket();
debug("ok: switch cmd: KILL.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("LIST"))
{
debug("ok: switch cmd: LIST.start.");
if(pHandleSftpCommandPacket->sArgs.size() < 1)
{
printf("ERR: unexpected command:%s.\n",pHandleSftpCommandPacket->sCommand.c_str());
packSftpMessagePacket("-ERR: server received unexpected command");
packTcpPacket();
continue;
}
pHandleSftpCommandPacket->sArgFirst = pHandleSftpCommandPacket->sArgs.substr(0,1);
pHandleSftpCommandPacket->sArgFirst = toUpString(pHandleSftpCommandPacket->sArgFirst);
if(pHandleSftpCommandPacket->sArgs.size() > 2)
{
if(pHandleSftpCommandPacket->sArgs[0] == '/')
{
pHandleSftpCommandPacket->sArgs.erase(0,1);
}
pHandleSftpCommandPacket->sArgSecond = pHandleSftpCommandPacket->sArgs.substr(2);
}
else
{
pHandleSftpCommandPacket->sArgSecond = "";
}
struct dirent * tpDirent = NULL;
DIR * tpDirectory = NULL;
string tsDirectoryToList = pSession->sCurrentPath + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond;
string tsList = "";
struct stat tStat;
string tsFileAddress;
string tsLine = "";
tpDirectory = opendir(tsDirectoryToList.c_str());
if( tpDirectory == NULL)
{
printf("ERR: unexpected directory to list:%s.\n",tsDirectoryToList.c_str());
packSftpMessagePacket("-ERR: unexpected directory to list.");
packTcpPacket();
continue;
}
if(dbug)cout<<"ok: directory to list:"<<tsDirectoryToList<<endl;
if(!pHandleSftpCommandPacket->sArgFirst.compare("F"))
{
tsList = "+" + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond + "\n";
while((tpDirent = readdir(tpDirectory)))
{
if(tsList.size() + 15 >= tcpLoadMax || tsList.size() + strlen(tpDirent->d_name) >= tcpLoadMax - 5 )
{
tsList.append("...etc...");
tsList.append("\n");
break;
}
tsList.append(tpDirent->d_name);
tsList.append("\n");
}
closedir(tpDirectory);
if(dbug)cout<<"ok: list:"<<endl<<tsList<<endl;
packSftpMessagePacket(tsList);
packTcpPacket();
tsList = "";
tsDirectoryToList = pSession->sCurrentPath + pSession->sCurrentPathForClient;
pHandleSftpCommandPacket->sArgFirst = "";
pHandleSftpCommandPacket->sArgSecond = "";
}
else if(!pHandleSftpCommandPacket->sArgFirst.compare("V"))
{
tsList = "+" + pSession->sCurrentPathForClient + pHandleSftpCommandPacket->sArgSecond + "\n";
while((tpDirent = readdir(tpDirectory)))
{
tsLine = "";
tsLine += tpDirent->d_name;
tsFileAddress = pSession->sCurrentPath + pSession->sCurrentPathForClient + tpDirent->d_name;
stat(tsFileAddress.c_str(), &tStat);
if(S_ISDIR(tStat.st_mode))//if folder
{
tsLine += "\t<LIST>...\n";
}
else
{
tsLine += "\t";
tsLine += decimalToString(tStat.st_size);
tsLine += "\t";
tsLine += time_tToString(tStat.st_mtime);
tsLine += "\n";
}
if(tsList.size() + 15 >= tcpLoadMax || tsList.size() + tsLine.size() >= tcpLoadMax - 5)
{
tsList.append("...etc...");
tsList.append("\n");
break;
}
else
{
tsList += tsLine;
}
}
closedir(tpDirectory);
if(dbug)cout<<"ok: list:"<<endl<<tsList<<endl;
packSftpMessagePacket(tsList);
packTcpPacket();
tsList = "";
tsDirectoryToList = pSession->sCurrentPath + pSession->sCurrentPathForClient;
pHandleSftpCommandPacket->sArgFirst = "";
pHandleSftpCommandPacket->sArgSecond = "";
}
else
{
printf("ERR: unexpected LIST argument:%s.\n",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: server received unexpected LIST argument.");
packTcpPacket();
tsList = "";
tsDirectoryToList = pSession->sCurrentPath + pSession->sCurrentPathForClient;
pHandleSftpCommandPacket->sArgFirst = "";
pHandleSftpCommandPacket->sArgSecond = "";
continue;
}
debug("ok: switch cmd: LIST.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("CDIR"))
{
debug("ok: switch cmd: CDIR.start.");
if(pHandleSftpCommandPacket->sArgs[0] == '/')
{
pHandleSftpCommandPacket->sArgs.erase(0,1);
}
if(pHandleSftpCommandPacket->sArgs.size() > 0)
{
if(pHandleSftpCommandPacket->sArgs[pHandleSftpCommandPacket->sArgs.size()-1] != '/')
{
pHandleSftpCommandPacket->sArgs += "/";
}
}
DIR * tpDirectoryCdir = NULL;
string tsDirectoryToCdir = pSession->sCurrentPath + pHandleSftpCommandPacket->sArgs;
tpDirectoryCdir = opendir(tsDirectoryToCdir.c_str());
if( tpDirectoryCdir == NULL)
{
printf("ERR: unexpected real directory to change to:%s.\n",tsDirectoryToCdir.c_str());
packSftpMessagePacket("-ERR: unexpected directory to chang to.");
packTcpPacket();
continue;
}
if(dbug)cout<<"ok: real directory to change to:"<<tsDirectoryToCdir<<endl;
packSftpMessagePacket("!Changed working dir to /"+pHandleSftpCommandPacket->sArgs);
packTcpPacket();
pSession->sCurrentPathForClient = pHandleSftpCommandPacket->sArgs;
cout<<"ok: sCurrentPathForClient:/"<<pSession->sCurrentPathForClient<<endl;
debug("ok: switch cmd: CDIR.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("TYPE"))
{
debug("ok: switch cmd: TYPE.start.");
packSftpMessagePacket("-This server is binary mode only.");
packTcpPacket();
debug("ok: switch cmd: TYPE.end.");
}
else if(!pHandleSftpCommandPacket->sCmd.compare("DONE"))
{
debug("ok: switch cmd: DONE.start.");
packSftpMessagePacket("+.");///need change
packTcpPacket();
debug("ok: switch cmd: DONE.end.");
break;
}
else
{
printf("ERR: unexpected command:%s.",pHandleSftpCommandPacket->sArgs.c_str());
packSftpMessagePacket("-ERR: server received unexpected command");
packTcpPacket();
continue;
}
printf("\nok: finished command: \"%s\".%s.\n\n",pHandleSftpCommandPacket->sCommand.c_str(),timeStamp());
pSession->commandTimer = clock() - pSession->commandTimer;
printf("ok: handeling this command costs: %i s.\n",pSession->commandTimer/CLOCKS_PER_SEC);
}//while(1)//each loop for each command
printf("\nok: finished command: \"DONE\".\n");
pSession->commandTimer = clock() - pSession->commandTimer;
printf("ok: handeling this command costs: %i s.\n",pSession->commandTimer/CLOCKS_PER_SEC);
pSession->sessionClosed = 0;
close(pSession->localSocket);
debug("ok: child: close(localSocket).");
exit(0);
}
