public String ReadFile(int rootBeginAddr)
{
List <String> ls = new List <String>();
BitArray rootFCBArray = GetBitArray(rootBeginAddr, 128);
FCB rootFCB = new FCB(rootFCBArray, rootBeginAddr);
BitArray blockArray = GetBitArray(rootFCB.indexBlock * blockSize, blockSize);
IndexBlock indexBlock = new IndexBlock(blockArray);
int i, j;
while (indexBlock.IsFull())
{
for (i = 0; i < 31; ++i)
{
int curBlock = indexBlock.indexes[i];
ls.Add(GetString(curBlock * 512, 64));
}
int nextBlock = indexBlock.indexes[31];
for (i = 0; i < blockSize; ++i)
{
blockArray[i] = disk[i + nextBlock * blockSize];
}
indexBlock.ChangeBlock(blockArray);
}
for (i = 0; i < indexBlock.endIndex - 1; ++i)
{
int curBlock = indexBlock.indexes[i];
ls.Add(GetString(curBlock * 512, 64));
}
String s = GetString(indexBlock.indexes[i] * blockSize, rootFCB.endOffset);
int totLen = ls.Count * 64 + s.Length;
char[] t = new char[totLen];
j = 0;
i = 0;
foreach (String str in ls)
{
for (j = 0; j < 64; ++j)
{
t[i] = str[j];
i++;
}
}
for (j = 0; j < s.Length; ++j)
{
t[i] = s[j];
i++;
}
return(new String(t));
}
public bool CreateFile(int rootBeginAddr, String fileName, bool isFolder)
{
if (GetInt(16, 21) == 0)
{
return(false);
}
if (CountFreeBlock() < 2)
{
return(false);
}
int nextFCB = GetNextFreeFCB();
if (nextFCB == 0)
{
return(false); //无空闲FCB，创建失败
}
int nextBlock = GetNextFreeBlock();
if (nextBlock == 0)
{
return(false); //无空闲块，创建失败
}
SetString(nextFCB, fileName);
disk[nextFCB + 96] = isFolder;
SetInt(nextBlock, nextFCB + 97, 16);
int temp = nextBlock;
nextBlock = GetNextFreeBlock();
if (nextBlock == 0)
{
return(false); //无空闲块，创建失败
}
SetInt(nextBlock, temp * blockSize, 16);
BitArray childBeginAddr = new BitArray(32, false);
BitArray chFCB = GetBitArray(nextFCB, 128);
FCB t = new FCB(chFCB, nextFCB);
int i;
for (i = 0; i < 21; ++i)
{
int val = 1 << i;
childBeginAddr[20 - i] = ((nextFCB & val) == val);
}
return(WriteFile(rootBeginAddr, childBeginAddr));
}
public ArrayList GetAllChildType(int rootBeginAddr)
{
ArrayList allChild = new ArrayList();
BitArray rootFCBArray = GetBitArray(rootBeginAddr, 128);
FCB rootFCB = new FCB(rootFCBArray, rootBeginAddr);
BitArray blockArray = GetBitArray(rootFCB.indexBlock * blockSize, blockSize);
IndexBlock indexBlock = new IndexBlock(blockArray);
int i, j;
while (indexBlock.IsFull())
{
for (i = 0; i < 31; ++i)
{
int curBlock = indexBlock.indexes[i];
for (j = 0; j < 16; ++j)
{
allChild.Add(disk[GetInt(curBlock * blockSize + 32 * j, 21) + 96]);
}
}
int nextBlock = indexBlock.indexes[31];
for (i = 0; i < blockSize; ++i)
{
blockArray[i] = disk[i + nextBlock * blockSize];
}
indexBlock.ChangeBlock(blockArray);
}
for (i = 0; i < indexBlock.endIndex - 1; ++i)
{
int curBlock = indexBlock.indexes[i];
for (j = 0; j < 16; ++j)
{
allChild.Add(disk[GetInt(curBlock * blockSize + 32 * j, 21) + 96]);
}
}
for (j = 0; j * 32 < rootFCB.endOffset; ++j)
{
allChild.Add(disk[GetInt(indexBlock.indexes[i] * blockSize + 32 * j, 21) + 96]);
}
return(allChild);
}
public void DeleteFile(int rootBeginAddr)
{
bool isFolder = disk[rootBeginAddr + 96];
int i;
if (isFolder)
{
BitArray rootFCBArray = GetBitArray(rootBeginAddr, 128);
FCB rootFCB = new FCB(rootFCBArray, rootBeginAddr);
BitArray blockArray = GetBitArray(rootFCB.indexBlock * blockSize, blockSize);
IndexBlock indexBlock = new IndexBlock(blockArray);
indexBlock.num = rootFCB.indexBlock;
int j;
while (indexBlock.IsFull())
{
for (i = 0; i < 31; ++i)
{
int curBlock = indexBlock.indexes[i];
for (j = 0; j < 16; ++j)
{
DeleteFile(GetInt(curBlock * blockSize + 32 * j, 21));
}
}
int nextBlock = indexBlock.indexes[31];
for (i = 0; i < 512; ++i)
{
disk[indexBlock.num * blockSize + i] = false;//将数据擦除
}
SetInt(GetInt(0, 16), indexBlock.num * blockSize, 16);
SetInt(indexBlock.num, 0, 16);
SetInt(GetInt(256, 16) + 1, 256, 16);
for (i = 0; i < blockSize; ++i)
{
blockArray[i] = disk[i + nextBlock * blockSize];
}
indexBlock.ChangeBlock(blockArray);
indexBlock.num = nextBlock;
}
for (i = 0; i < indexBlock.endIndex - 1; ++i)
{
int curBlock = indexBlock.indexes[i];
for (j = 0; j < 16; ++j)
{
DeleteFile(GetInt(curBlock * blockSize + 32 * j, 21));
}
}
for (j = 0; j * 32 < rootFCB.endOffset; ++j)
{
DeleteFile(GetInt(indexBlock.indexes[i] * blockSize + 32 * j, 21));
}
for (i = 0; i < 512; ++i)
{
disk[indexBlock.num * blockSize + i] = false;//将数据擦除
}
SetInt(GetInt(0, 16), indexBlock.num * blockSize, 16);
SetInt(indexBlock.num, 0, 16);
SetInt(GetInt(256, 16) + 1, 256, 16);
}
else
{
BitArray rootFCBArray = GetBitArray(rootBeginAddr, 128);
FCB rootFCB = new FCB(rootFCBArray, rootBeginAddr);
BitArray blockArray = GetBitArray(rootFCB.indexBlock * blockSize, blockSize);
IndexBlock indexBlock = new IndexBlock(blockArray);
indexBlock.num = rootFCB.indexBlock;
int j;
while (indexBlock.IsFull())
{
for (i = 0; i < 31; ++i)
{
int curBlock = indexBlock.indexes[i];
for (j = 0; j < 512; ++j)
{
disk[curBlock * blockSize + j] = false;//将数据擦除
}
SetInt(GetInt(0, 16), curBlock * blockSize, 16);
SetInt(curBlock, 0, 16);
SetInt(GetInt(256, 16) + 1, 256, 16);
}
int nextBlock = indexBlock.indexes[31];
for (i = 0; i < 512; ++i)
{
disk[indexBlock.num * blockSize + i] = false;//将数据擦除
}
SetInt(GetInt(0, 16), indexBlock.num * blockSize, 16);
SetInt(indexBlock.num, 0, 16);
SetInt(GetInt(256, 16) + 1, 256, 16);
for (i = 0; i < blockSize; ++i)
{
blockArray[i] = disk[i + nextBlock * blockSize];
}
indexBlock.ChangeBlock(blockArray);
indexBlock.num = nextBlock;
}
for (i = 0; i < indexBlock.endIndex; ++i)
{
int curBlock = indexBlock.indexes[i];
for (j = 0; j < 512; ++j)
{
disk[curBlock * blockSize + j] = false;//将数据擦除
}
SetInt(GetInt(0, 16), curBlock * blockSize, 16);
SetInt(curBlock, 0, 16);
SetInt(GetInt(256, 16) + 1, 256, 16);
}
for (j = 0; j < 512; ++j)
{
disk[indexBlock.num * blockSize + j] = false;//将数据擦除
}
SetInt(GetInt(0, 16), indexBlock.num * blockSize, 16);
SetInt(indexBlock.num, 0, 16);
SetInt(GetInt(256, 16) + 1, 256, 16);
}
for (i = 0; i < 128; ++i)
{
disk[rootBeginAddr + i] = false;//擦除PCB
}
SetInt(GetInt(16, 21), rootBeginAddr, 21);
SetInt(rootBeginAddr, 16, 21);
}
public bool WriteFile(int rootBeginAddr, BitArray dataBitset)
{
int i;
BitArray rootFCBArray = GetBitArray(rootBeginAddr, 128);
FCB rootFCB = new FCB(rootFCBArray, rootBeginAddr);
BitArray blockArray = GetBitArray(rootFCB.indexBlock * blockSize, blockSize);
IndexBlock indexBlock = new IndexBlock(blockArray);
indexBlock.num = rootFCB.indexBlock;
while (indexBlock.IsFull())
{
int nextBlock = indexBlock.indexes[31];
for (i = 0; i < blockSize; ++i)
{
blockArray[i] = disk[i + nextBlock * blockSize];
}
indexBlock.ChangeBlock(blockArray);
indexBlock.num = nextBlock;
}
int endAddr = rootFCB.endOffset + indexBlock.indexes[indexBlock.endIndex - 1] * blockSize;
for (i = 0; i < dataBitset.Length; ++i)
{
disk[endAddr] = dataBitset[i];
if (endAddr % blockSize == (blockSize - 1)) //当前块被写满
{
if (indexBlock.endIndex == 31) //索引块被写满
{
int nextBlock = GetNextFreeBlock();
if (nextBlock == 0)
{
return(false); //磁盘已满，写入失败
}
SetInt(nextBlock, indexBlock.num * blockSize + 16 * 31, 16);
int j;
for (j = 0; j < blockSize; ++j)
{
blockArray[j] = disk[j + indexBlock.num * blockSize];
}
int temp = nextBlock;
nextBlock = GetNextFreeBlock();
SetInt(nextBlock, temp * blockSize, 16);
indexBlock.ChangeBlock(blockArray);
indexBlock.num = temp;
endAddr = nextBlock * blockSize;
indexBlock.endIndex = 1;
}
else
{
int nextBlock = GetNextFreeBlock();
if (nextBlock == 0)
{
return(false); //磁盘已满，写入失败
}
SetInt(nextBlock, indexBlock.num * blockSize + indexBlock.endIndex * 16, 16);
indexBlock.endIndex++;
endAddr = nextBlock * blockSize;
}
}
else
{
endAddr++;
}
}
int offset = endAddr % blockSize;
SetInt(offset, rootBeginAddr + 113, 9);
return(true);
}
