int load_file(char *file)
{
FILE *fp;
fp=fopen(file,"r");
if(!fp){
fputs("vm: Error in opening file!\n",stderr);
return -1;
}
long int size=fSize(fp);
buff=(char*)malloc(size);
if(!buff){
fputs("vm: Unable to initialize mem\n",stderr);
return -1;
}
long int rs=fread(buff,1,size,fp);
fclose(fp);
return rs;
}
void HandleTCPClient(int clntSocket){
int fileSize;
int bytesToWrite;
int totalBytesSent, bytesSent;
int bytesRcvd, totalBytesRcvd;
char fileSizeInString[20];
char fileName[256];
char stringBuffer[BUFSIZE];
char fileBuffer[FILEBUFSIZE];
char msgType=0;
char echoStringLengthInString[20];
int echoStringLength;
FILE *fp;
/* receive "hello" */
memset(stringBuffer, 0, BUFSIZE);
if(recv(clntSocket, stringBuffer, BUFSIZE, 0) <0){
DieWithError("recv() failed");
}
printf("Msg< %s\n", stringBuffer);
/* send "hi" */
memset(stringBuffer, 0, BUFSIZE);
strcpy(stringBuffer, "hi");
if(send(clntSocket, stringBuffer, BUFSIZE, 0) != BUFSIZE)
DieWithError("send() sent a different number of bytes than expected");
printf("Msg> %s\n\n", stringBuffer);
while(msgType != Exit){
/* reset string variables */
memset(fileSizeInString, 0, 20);
memset(fileName, 0, 256);
memset(fileBuffer, 0, FILEBUFSIZE);
memset(stringBuffer, 0, BUFSIZE);
memset(echoStringLengthInString, 0, 20);
/* receive msgType from client */
if((bytesRcvd = recv(clntSocket, &msgType, 1, 0)) <=0){
DieWithError("recv() failed");
}
if(msgType == EchoReq){
totalBytesRcvd = 0;
msgType = EchoRep;
if(send(clntSocket, &msgType, 1, 0) != 1)
DieWithError("send() sent a different number of bytes than expected");
if((bytesRcvd = recv(clntSocket, echoStringLengthInString, 20, 0)) <0)
DieWithError("recv() failed");
echoStringLength = atoi(echoStringLengthInString);
if(echoStringLength > BUFSIZE){ /* if string length exceeds buffer length */
totalBytesRcvd = 0;
while(totalBytesRcvd < echoStringLength){
if((bytesRcvd = recv(clntSocket, stringBuffer, BUFSIZE-1, 0)) <0)
DieWithError("recv() failed");
printf("Msg<%s\n", stringBuffer);
if( send(clntSocket, stringBuffer, bytesRcvd,0) != bytesRcvd){
DieWithError("send() failed");
}
printf("Msg>%s\n", stringBuffer);
totalBytesRcvd += bytesRcvd;
memset(stringBuffer, 0, BUFSIZE);
}
}
else{ /* if string length does not exceed buffer length */
if((bytesRcvd = recv(clntSocket, stringBuffer, BUFSIZE, 0)) <0)
DieWithError("recv() failed");
printf("Msg<%s\n", stringBuffer);
if( send(clntSocket, stringBuffer, bytesRcvd,0) != bytesRcvd){
DieWithError("send() failed");
}
printf("Msg>%s\n", stringBuffer);
}
}
else if(msgType == FileUploadReq){
/* receive name of file clients wants to upload */
if((bytesRcvd = recv(clntSocket, fileName, 256, 0)) <0)
DieWithError("recv() failed");
printf("File name client will upload: %s\n", fileName);
/* receive size of file */
if((bytesRcvd = recv(clntSocket, fileSizeInString, 20, 0)) <0)
{
DieWithError("recv() failed");
}
fileSize = atoi(fileSizeInString);
printf("File size that client will send: %d\n", fileSize);
/* send ACK */
msgType = FILEACK;
if(send(clntSocket, &msgType, 1, 0) != 1)
DieWithError("send() sent a different number of bytes than expected");
//open file
fp = fopen(fileName, "wb");
if(fp == NULL)
{
DieWithError("File open error");
}
/* receive file contents */
printf("Receiving => ");
totalBytesRcvd = 0;
while(totalBytesRcvd < fileSize){
/* if number of bytes left to receive is smaller than file buffer size, receive the number of bytes left, not the whole file buffer length*/
if(fileSize - totalBytesRcvd < FILEBUFSIZE){
bytesToWrite = fileSize - totalBytesRcvd;
}
else{ /* if number of bytes left to receive is bigger than file buffer, receive whole buffer size */
bytesToWrite = FILEBUFSIZE;
}
if((bytesRcvd = recv(clntSocket, fileBuffer, FILEBUFSIZE, 0)) <0)
DieWithError("recv() failed");
printf("#");
fwrite(fileBuffer, sizeof(char), bytesToWrite, fp);/* write to file */
totalBytesRcvd += bytesRcvd;
memset(fileBuffer, 0, FILEBUFSIZE);
}
fclose(fp);
printf("\n");
printf("%s (%d bytes) successfully received from client\n", fileName, fileSize);
printf("Waiting for operation from client...\n\n");
}
else if(msgType == FileDownloadReq){
/* receive name of file client wants to download */
if((bytesRcvd = recv(clntSocket, fileName, 256, 0)) <0)
DieWithError("recv() failed");
printf("Received name of file client wants to download: %s\n", fileName);
fileSize = fSize(fileName);
sprintf(fileSizeInString, "%d", fileSize);
/* open file. if file does not exist, send error message to client. */
fp = fopen(fileName, "r");
if(fp == NULL){
printf("File does not exist. Sending error message to client.\n");
printf("Waiting for operation from client...\n\n");
msgType = FileDownloadError;
if(send(clntSocket, &msgType, 1, 0) != 1)
DieWithError("send() sent a different number of bytes than expected");
continue;
}
else{
msgType = FileDownloadReady;
if(send(clntSocket, &msgType, 1, 0) != 1)
DieWithError("send() sent a different number of bytes than expected");
}
/* send size of file client wants to download */
if(send(clntSocket, fileSizeInString, 20, 0) != 20)
DieWithError("send() sent a different number of bytes than expected");
printf("Sent size of file to client: %s\n", fileSizeInString);
/* receive ACK from client */
if((bytesRcvd = recv(clntSocket, &msgType, 1, 0)) <0){
DieWithError("recv() failed");
}
/* send file contents */
printf("Sending => ");
while( (fread(fileBuffer, 1, FILEBUFSIZE, fp)) > 0){
if((bytesSent = send(clntSocket, fileBuffer, FILEBUFSIZE, 0)) != FILEBUFSIZE)
DieWithError("send() sent a different number of bytes than expected");
printf("#");
totalBytesSent += bytesSent;
memset(fileBuffer, 0, FILEBUFSIZE);
}
fclose(fp);
printf("\n");
printf("%s (%d bytes) successfully sent to client\n", fileName, fileSize);
printf("Waiting for operation from client...\n\n");
}
else if(msgType == ListFilesReq){
fp = popen("ls -l", "r"); /* use popen to read result of "ls -l"*/
if(fp == NULL){
DieWithError("popen failed");
}
fread(fileBuffer, FILEBUFSIZE, 1, fp);
pclose(fp);
/* sent list of directory to client */
totalBytesSent = 0;
while(totalBytesSent < FILEBUFSIZE){
if((bytesSent = send(clntSocket, fileBuffer, FILEBUFSIZE, 0)) != FILEBUFSIZE)
DieWithError("send() sent a different number of bytes than expected");
totalBytesSent += bytesSent;
}
printf("Sent list of files on directory to client:");
printf(" %s", fileBuffer);
printf("Waiting for operation from client...\n\n");
}
}
printf("Client has disconnected.\nClosing socket.\n");
close(clntSocket);
}
