int fileSys::delBlock(string file, int block_number){
int i,first_blk = getFirstBlock(file);
if(check_n_pad(file) == 0)
return 0;
if(check_block(block_number, file) == 0)
return 0;
//check if the block_number belongs to the file
if(first_blk == block_number){
for(i = 0; i < firstBlock.size(); i++){
if(firstBlock[i] == block_number){
firstBlock[i] = fat[block_number];
fat[block_number] = fat[0];
fat[0] = block_number;
break;
}
}
}else{
for(i = 0; i < fat.size();i++){
if(fat[i] == block_number){
fat[i] = fat[block_number];
fat[block_number] = fat[0];
fat[0] = block_number;
break;
}
}
}
fsSynch();
return 1;
}
int Filesys::delBlock(std::string file, int blockNumber) {
int nextBlock = getFirstBlock(file);
// Can't delete block of empty file.
if (nextBlock == 0) { // File doesn't exist or is empty.
throw std::invalid_argument("Cannot delete block.");
return 0;
} else if (nextBlock == blockNumber) { // Block to del is first block.
for (int i = 0; i < fileName.size(); i++) {
if (fileName[i] == file) {
firstBlock[i] = fat[blockNumber];
}
}
} else { // Block to del is not first block.
while (fat[nextBlock] != blockNumber && fat[nextBlock] != 0) {
nextBlock = fat[nextBlock];
}
if (fat[nextBlock] != 0) {
fat[nextBlock] = fat[blockNumber];
} else {
throw std::invalid_argument("Block not in file.");
return 0;
}
}
fat[blockNumber] = fat[0];
fat[0] = blockNumber;
fssynch();
}
int Filesys::addBlock(std::string file, std::string block) {
int allocate;
int fileBlock = getFirstBlock(file);
if (fileBlock == -1) { // No available blocks; fs full.
throw std::invalid_argument("Cannot add block. File doesn't exist.");
return 0;
} else if (fileBlock == 0) { // No blocks in file, OK to add.
allocate = fat[0];
if (allocate == 0) { // Disk is full.
throw std::invalid_argument("Disk is full, cannot add block.");
return -1;
} else {
fat[0] = fat[fat[0]];
fat[allocate] = 0;
// Update root
for (int i = 0; i < fileName.size(); i++) {
if (fileName[i] == file) {
firstBlock[i] = allocate;
}
}
}
} else { // File already has blocks.
allocate = fat[0];
fat[0] = fat[fat[0]];
fat[allocate] = 0;
// Follow links to change previous last block.
while (fat[fileBlock] != 0) {
fileBlock = fat[fileBlock];
}
fat[fileBlock] = allocate;
}
fssynch();
putBlock(allocate, block);
return allocate;
}
int Filesys::checkBlock(std::string file, int blockNumber) {
int nextBlock = getFirstBlock(file);
if (nextBlock == blockNumber) {
return 1;
} else {
while (fat[nextBlock] != 0) {
nextBlock = fat[nextBlock];
if (nextBlock == blockNumber) {
return 1;
}
}
// When here blockNumber is not a part of the file.
return 0;
}
}
int fileSys::check_block(int block, string file){
int next_block, first_blk = getFirstBlock(file);
bool found = false;
next_block = first_blk;
while(next_block != 0){
if(next_block == block){
found = true;
break;
}
next_block = fat[next_block];
}
if(found == false){
cout << "getBlock(): Hey! That block number does not belong to that file. (Block: "<< block << ")" << endl;
return 0;
}
return 1;
}
int Filesys::rmFile(std::string file) {
for (int i = 0; i < fileName.size(); i++) {
if (fileName[i] == file) {
// Don't remove if firstblock is not empty.
if (getFirstBlock(file) != 0) {
throw std::invalid_argument("Cannot remove non-empty file.");
return 0;
} else {
// File is empty and thus removeable.
fileName[i] = "xxxxx";
fssynch();
return 1;
}
}
}
// File doesn't exist.
throw std::invalid_argument("Cannot delete file that doesn't exist.");
return 0;
}
//returns -1 if disk is full and -2 if file wasnt found
int fileSys::addBlock(string file, string buffer){
int first_blk = getFirstBlock(file), new_blk = fat[0];
bool file_found = false;
if(check_n_pad(file) == 0)
return -1;
if(new_blk == 0){
cout << "Disk is full!\n";
return -1;
}
if(first_blk == 0){//then empty file
for(int i = 0; i < fileName.size(); i++){
if(fileName[i] == file){
firstBlock[i] = new_blk;
fat[0] = fat[new_blk];
fat[new_blk] = 0;
file_found = true;
break;
}
}
if(file_found == false){
cout << "addBlock(): File was not found!\n";
return -2;
}
}else{
int next_blk = first_blk;
while(fat[next_blk] != 0)
next_blk = fat[next_blk];
fat[next_blk] = new_blk;
fat[0] = fat[new_blk];
fat[new_blk] = 0;
}
disk.putblock(new_blk, buffer);
fsSynch();
return new_blk;
}//addblock
