/**
* Read file
*
* @param {char *} fileName
* @param {int} socketFd
*/
void readFile(char *fileName, int socketFd)
{
if (fileExists(fileName) == 0) {
attemptWrite(socketFd, FILE_NOT_FOUND, strlen(FILE_NOT_FOUND));
printf("File not found.\n");
return;
}
FILE *fp = fopen(fileName, "r");
if (fp == NULL) {
printf("File could not be opened.\n");
return;
}
char *fileContents, *line;
long fileLength;
size_t length;
ssize_t read;
fseek(fp, 0, SEEK_END);
fileLength = ftell(fp);
fseek(fp, 0, SEEK_SET);
fileContents = malloc(fileLength);
if (fileContents) {
fread(fileContents, 1, fileLength, fp);
}
attemptWrite(socketFd, fileContents, strlen(fileContents));
fclose(fp);
}
/**
* Handle ftp read
*
* @param {int} clientId
* @param {int} clientSocketFd
* @param {char *} fileName
*/
void handleFtpRead(int clientId, int clientSocketFd, char *fileName)
{
if (fileExists(fileName)) {
printf("Client #%d - File found: `%s`\n", clientId, fileName);
readFile(fileName, clientSocketFd);
} else {
printf("Client #%d - File not found: `%s`\n", clientId, fileName);
attemptWrite(clientSocketFd, FILE_NOT_FOUND, strlen(FILE_NOT_FOUND));
}
}
void NoStarveReadWriteMutex::acquireWrite() const
{
// if we can acquire the rwlock the easy way, we're done
if (attemptWrite()) {
return;
}
// failed to get the rwlock, do it the hard way:
// locking the mutex and setting writerWaiting will cause all new readers to
// block on the mutex rather than on the rwlock.
mutex_.lock();
writerWaiting_ = true;
ReadWriteMutex::acquireWrite();
writerWaiting_ = false;
mutex_.unlock();
}
bool NoStarveReadWriteMutex::timedWrite(int64_t milliseconds) const
{
// if we can acquire the rwlock the easy way, we're done
if (attemptWrite()) {
return true;
}
// failed to get the rwlock, do it the hard way:
// locking the mutex and setting writerWaiting will cause all new readers to
// block on the mutex rather than on the rwlock.
if (!mutex_.timedlock(milliseconds)) {
return false;
}
writerWaiting_ = true;
int ret = ReadWriteMutex::timedWrite(milliseconds);
writerWaiting_ = false;
mutex_.unlock();
return ret == 0;
}
/**
* Handle a new connection
*
* @param {int} newSocketFd
*/
void handleConnection(int newSocketFd)
{
char ioBuffer[256];
memset(ioBuffer, '\0', 256); // reset the ioBuffer for i/o
attemptRead(newSocketFd, ioBuffer, 255);
printf("Before call to isValidClientId(), ");
printClients();
int clientId = atoi(ioBuffer);
int isValidId = isValidClientId(clientId);
printf("Checking for valid client id...\n");
if (isValidId == 0) {
attemptWrite(newSocketFd, INVALID_CLIENT_ID, strlen(INVALID_CLIENT_ID));
return;
} else {
attemptWrite(newSocketFd, VALID_CLIENT_ID, strlen(VALID_CLIENT_ID));
memset(ioBuffer, '\0', 256); // reset the ioBuffer for i/o
attemptRead(newSocketFd, ioBuffer, 255);
printf("%s\n", ioBuffer); // print client id response message from client
addClient(clientId);
printf("After call to addClient(), ");
printClients();
attemptWrite(newSocketFd, WELCOME_MESSAGE, strlen(WELCOME_MESSAGE));
printf("New client #%d\n", clientId);
while (1) {
printf("Waiting for command from client #%d...\n", clientId);
char opFile[256];
// read opFile from client
memset(ioBuffer, '\0', 256); // reset the ioBuffer for i/o
attemptRead(newSocketFd, ioBuffer, 255);
strcpy(opFile, ioBuffer);
// if client requests, end session
if (strcmp(ioBuffer, END_SESSION) == 0) {
printf("Terminating client #%d\n", clientId);
removeClient(clientId);
return;
}
// otherwise, send continue response
attemptWrite(newSocketFd, CONTINUE, strlen(CONTINUE));
// read opCode from client
memset(ioBuffer, '\0', 256); // reset the ioBuffer for i/o
attemptRead(newSocketFd, ioBuffer, 255);
// proceed based on opCode
if (strcmp(ioBuffer, PROCESS_READ) == 0) {
printf("Processing read for file: `%s`\n", opFile);
readFile(opFile, newSocketFd); // send file to client
} else if (strcmp(ioBuffer, PROCESS_WRITE) == 0) {
printf("Processing write for file: `%s`\n", opFile);
attemptWrite(newSocketFd, CONTINUE, strlen(CONTINUE));
memset(ioBuffer, '\0', 256);
attemptRead(newSocketFd, ioBuffer, 255); // read file contents
writeToFile(opFile, ioBuffer);
}
}
}
}
