/*
* Get the inumber for the given file. Also makes sure that the cursor
* is within the file.
*/
int
Fileops_getinumber(int fd, int *size)
{
int inumber;
struct inode in;
int err;
inumber = pathname_lookup(unixfs, openFileTable[fd].pathname);
if (inumber < 0) {
return inumber; // Can't find file
}
err = inode_iget(unixfs, inumber,&in);
if (err < 0) {
return err;
}
if (!(in.i_mode & IALLOC)) {
return -1;
}
*size = inode_getsize(&in);
//if (openFileTable[fd].cursor >= size) return -1; // Finished with file
return inumber;
}
/*
* Output to the specified file the checksum of all allocated inodes.
*
* This is used by the grading script, so be careful not to change its output
* format.
*/
void
DumpInodeChecksum(struct unixfilesystem *fs, FILE *f)
{
for (int inumber = 1; inumber < fs->superblock.s_isize*16; inumber++) {
struct inode in;
if (inode_iget(fs, inumber, &in) < 0) {
fprintf(stderr,"Can't read inode %d \n", inumber);
return;
}
if ((in.i_mode & IALLOC) == 0) {
// Skip this inode if it's not allocated.
continue;
}
char chksum[CHKSUMFILE_SIZE];
if (chksumfile_byinumber(fs, inumber, chksum) < 0) {
fprintf(stderr, "Inode %d can't compute chksum\n", inumber);
continue;
}
char chksumstring[CHKSUMFILE_STRINGSIZE];
chksumfile_cvt2string(chksum, chksumstring);
int size = inode_getsize(&in);
fprintf(f, "Inode %d mode 0x%x size %d checksum %s\n",inumber,in.i_mode, size, chksumstring);
}
}
/*
* Print all the entries in the specified directory.
*/
void PrintDirectory(struct unixfilesystem *fs, char *pathname)
{
int inumber = pathname_lookup(fs, pathname);
if (inumber < 0) {
fprintf(stderr, "Can't find %s\n", pathname);
return;
}
struct direntv6 direntries[1000];
int numentries = GetDirEntries(fs, inumber, direntries, 1000);
if (numentries < 0) {
fprintf(stderr, "Can't read entries from %s\n", pathname);
return;
}
struct inode in;
int i, rowLength = 0;
for (i = 0; i < numentries; i++) {
inode_iget(fs, direntries[i].d_inumber, &in);
printf("%s",direntries[i].d_name);
if ((in.i_mode & IFMT) == IFDIR)
printf("/");
printf("\t");
rowLength += strlen(direntries[i].d_name) + 1;
if ((i+1) % 6 == 0)
puts("");
}
}
/*
* Lookup the specified name (name) in the directory (dirinumber). If found, return the
* directory entry in dirEnt. Return 0 on success and something negative on failure.
*/
int
directory_findname(struct unixfilesystem *fs, const char *name,
int dirinumber, struct direntv6 *dirEnt)
{
struct inode ino;
if(inode_iget(fs, dirinumber, &ino) == -1) return -1;
if((ino.i_mode & IFMT) != IFDIR) return -1;
//traverse the inodes datablocks forloop
//compare the given file with directory entries
int size = inode_getsize(&ino);
int numBlocks = (size + DISKIMG_SECTOR_SIZE - 1) / DISKIMG_SECTOR_SIZE;
for(int block = 0; block < numBlocks; block++) {
struct direntv6 buffer[DISKIMG_SECTOR_SIZE / sizeof(struct direntv6)]; //an array of direntv6s
int validBytes = file_getblock(fs, dirinumber, block, &buffer);
if(validBytes < 0) return -1;
int dirsPerBlock = validBytes / sizeof(struct direntv6); //calculate the number of dirsPerBlock based on validBytes of block
for(int dir = 0; dir < dirsPerBlock; dir++) {
if(strcmp(name, buffer[dir].d_name) == 0) { //copy memory into the direntv6 only if name is found in block
memcpy(dirEnt, &buffer[dir], sizeof(struct direntv6));
return 0;
}
}
}
return -1;
}
/*
* Fetch the specified file block from the specified inode.
* Return the number of valid bytes in the block, -1 on error.
*/
int
file_getblock(struct unixfilesystem *fs, int inumber, int blockNum, void *buf)
{
// First retrieve the inode in question
struct inode node;
int inode_iget_status = inode_iget(fs, inumber, &node);
if (inode_iget_status == -1)
return -1;
// Then we want to get the block
int block = inode_indexlookup(fs, &node, blockNum);
if (!block)
return -1;
// Now retrive the contents of the block and put it into the buffer
int sector_status = diskimg_readsector(fs->dfd, block, buf);
// Figure out what the size was supposed to be
int inodesize = inode_getsize(&node);
// Now figure out what the valid number of bytes to return is
int bytesRemaining = inodesize - blockNum * 512;
if (bytesRemaining < 512) {
return bytesRemaining;
}
return sector_status;
}
struct unixfilesystem *
unixfilesystem_format(int dfd)
{
uint16_t bootblock[256];
bootblock[0] = BOOTBLOCK_MAGIC_NUM;
diskimg_writesector(dfd, BOOTBLOCK_SECTOR, bootblock);
struct unixfilesystem *fs = malloc(sizeof(struct unixfilesystem));
if (fs == NULL) {
fprintf(stderr,"Out of memory.\n");
return NULL;
}
fs->dfd = dfd;
// 144 inodes in total, so we have 8 blocks
// to store inodes, plus 2 start blocks,
// we have 10 blocks in use, and we allocate the entire volume 110 blocks
// so the rest 100 blocks is file blocks, and all blocks formats to free.
fs->superblock.s_isize = 144;
fs->superblock.s_fsize = 110; // 110 blocks of entire volume
fs->superblock.s_ninode = fs->superblock.s_isize; // at begining, free inodes number = total inodes number
int i;
// consider s_inode as bitmap
for (i = 0;i < 100;i++)
fs->superblock.s_inode[i] = 0;
fs->superblock.s_nfree = fs->superblock.s_fsize ; // at begining, free blocks number = total blocks number
// consider s_free as bitmap
for (i = 0;i < 100;i++)
fs->superblock.s_free[i] = 0;
diskimg_writesector(dfd, SUPERBLOCK_SECTOR, &fs->superblock);
int inumber = filsys_allocInode(fs);
if (inumber != ROOT_INUMBER) {
fprintf(stderr, "ROOT_INUMBER is not 1, format failed\n");
return -1;
}
struct inode in;
inode_iget(fs, inumber, &in);
// format the root dir, and set the i_mode field to DIR
inode_format(&in);
//in.i_mode &= (0xffff - IFMT);
in.i_mode |= IFDIR;
inode_iwrite(fs, ROOT_INUMBER, &in);
fs->workDirInumber = ROOT_INUMBER;
strcpy(fs->workDirName, "/");
return fs;
}
/*
* Fetch as many entries from a directory that will fit in the specified array. Return the
* number of entries found.
*/
int
GetDirEntries(struct unixfilesystem *fs, int inumber, struct direntv6 *entries, int maxNumEntries)
{
struct inode in;
int err = inode_iget(fs, inumber, &in);
if (err < 0) {
fprintf(stderr, "GetDirEntries using inode_iget err\n");
return err;
}
if (!(in.i_mode & IALLOC) || ((in.i_mode & IFMT) != IFDIR)) {
/* Not allocated or not a directory */
fprintf(stderr, "GetDirEntries inode is not dir or not allocated %d %d\n",in.i_mode & IALLOC, (in.i_mode & IFMT) == IFDIR);
return -1;
}
if (maxNumEntries < 1) {
fprintf(stderr, "maxNumEntries = %d\n",maxNumEntries);
return -1;
}
int size = inode_getsize(&in);
assert((size % sizeof(struct direntv6)) == 0);
int count = 0;
/* block number in the directory */
int numBlocks = (size + DISKIMG_SECTOR_SIZE - 1) / DISKIMG_SECTOR_SIZE;
/* buf to get bytes from diskimg */
char buf[DISKIMG_SECTOR_SIZE];
struct direntv6 *dir = (struct direntv6 *) buf; // use direntv6 handle
int bno;
for (bno = 0; bno < numBlocks; bno++) {
int bytesLeft, numEntriesInBlock, i;
bytesLeft = file_getblock(fs, inumber, bno, dir);
if (bytesLeft < 0) {
fprintf(stderr, "Error reading directory\n");
return -1;
}
numEntriesInBlock = bytesLeft / sizeof(struct direntv6);
for (i = 0; i < numEntriesInBlock ; i++) {
entries[count] = dir[i];
count++;
if (count >= maxNumEntries) return count;
}
}
return count;
}
/*
* Lookup the specified name (name) in the directory (dirinumber). If found, return the
* directory entry in dirEnt. Return 0 on success and something negative on failure.
*/
int directory_findname(struct unixfilesystem *fs, const char *name,
int dirinumber, struct direntv6 *dirEnt)
{
//return -1;
//fprintf(stderr, "directory_lookupname(name=%s dirinumber=%d)\n", name, dirinumber);
struct inode in;
int err = inode_iget(fs, dirinumber, &in);
if (err < 0) {
fprintf(stderr, "director_findname get inode error");
return -1;
}
if (!(in.i_mode & IALLOC) || ((in.i_mode & IFMT) != IFDIR)) {
fprintf(stderr, "director_findname dir inode is not IFDIR");
return -1;
}
int size = inode_getsize(&in);
assert((size % sizeof(struct direntv6)) == 0);
/* block number in the directory */
int numBlocks = (size + DISKIMG_SECTOR_SIZE - 1) / DISKIMG_SECTOR_SIZE;
/* buf to get bytes from diskimg */
char buf[DISKIMG_SECTOR_SIZE];
struct direntv6 *dir = (struct direntv6 *) buf; // use direntv6 handle
int bno;
for (bno = 0; bno < numBlocks; bno++) {
int bytesLeft, numEntriesInBlock, i;
bytesLeft = file_getblock(fs, dirinumber, bno, dir);
if (bytesLeft < 0) {
fprintf(stderr, "Error reading directory\n");
return -1;
}
numEntriesInBlock = bytesLeft / sizeof(struct direntv6);
for (i = 0; i < numEntriesInBlock ; i++) {
//printf("list = %s\n", dir[i].d_name);
if (strcmp(dir[i].d_name, name) == 0) {
*dirEnt = dir[i];
return 0;
}
}
}
//printf("Dir %d find name not find %s\n",dirinumber, name);
return -1;
}
/*
* Lookup the specified name (name) in the directory (dirinumber). If found, return the
* directory entry in dirEnt. Return 0 on success and something negative on failure.
*/
int
directory_findname(struct unixfilesystem *fs, const char *name,
int dirinumber, struct direntv6 *dirEnt)
{
// First fetch the inode corresponding to dirinumber
struct inode in;
int err = inode_iget(fs, dirinumber, &in);
if (err < 0) return err;
// Get the number of blocks
int size = inode_getsize(&in);
printf("size: %d\n", size);
int numBlocks = (size + DISKIMG_SECTOR_SIZE - 1) / DISKIMG_SECTOR_SIZE;
// Next access the block that has the directory entries
int numdirent = DISKIMG_SECTOR_SIZE / sizeof(struct direntv6);
struct direntv6 dir[numdirent];
// Cached for the strncp function
int targetlen = strlen(name);
// Loop through the blocks
for (int bno = 0; bno < numBlocks; bno++) {
// Get the number of bytes we want to consider
int bytes = file_getblock(fs, dirinumber, bno, dir);
// Loop through the directory entries
for (int i = 0; i < numdirent; i++) {
// Use strncmp to see if we have a match on the character name
if (strncmp(dir[i].d_name, name, targetlen) == 0) {
// Found it! Set values of dirEnt and return success
strncpy(dirEnt->d_name, dir[i].d_name, targetlen);
dirEnt->d_inumber = dir[i].d_inumber;
return 0;
}
}
}
return -1;
}
int remove_file(struct unixfilesystem *fs, int inumber)
{
struct inode in;
int err = inode_iget(fs, inumber, &in);
if (err < 0) return -1;
if (!(in.i_mode & IALLOC) || ((in.i_mode & IFMT) == IFDIR))
{
/* Not allocated or is a directory */
fprintf(stderr, "The input path is not a file and cannot be removed");
return -1;
}
if (in.i_nlink == 1) // only one link, so overwrite the file
{
char zeros[DISKIMG_SECTOR_SIZE] = {0};
int size = inode_getsize(&in);
int blockNum = 0;
// overwrite the file with zeros
for (blockNum = 0; blockNum < size / DISKIMG_SECTOR_SIZE; blockNum++)
{
char buf[DISKIMG_SECTOR_SIZE];
int blockAddress = inode_indexlookup(fs, &in, blockNum);
if (blockAddress == -1) {
fprintf(stderr, "Error looking up block number %d in inode %d", blockNum, inumber);
return -1;
}
if (diskimg_writesector(fs->dfd, blockAddress, &zeros) == -1)
{
fprintf(stderr, "Error overwriting file");
return -1;
}
}
}
else // multiple links to file, so only remove this link
{
in.i_nlink--;
}
return 0;
}
/*
* Fetch the next character from the file. Return -1 if at end of file.
*/
int
Fileops_getchar(int fd,int inumber, int size)
{
int inumber;
struct inode in;
unsigned char buf[DISKIMG_SECTOR_SIZE];
int bytesMoved;
int err, size;
int blockNo, blockOffset;
numgetchars++;
if (openFileTable[fd].pathname == NULL)
return -1; // fd not opened.
inumber = pathname_lookup(unixfs, openFileTable[fd].pathname);
if (inumber < 0) {
return inumber; // Can't find file
}
err = inode_iget(unixfs, inumber,&in);
if (err < 0) {
return err;
}
if (!(in.i_mode & IALLOC)) {
return -1;
}
size = inode_getsize(&in);
if (openFileTable[fd].cursor >= size) return -1; // Finished with file
blockNo = openFileTable[fd].cursor / DISKIMG_SECTOR_SIZE;
blockOffset = openFileTable[fd].cursor % DISKIMG_SECTOR_SIZE;
bytesMoved = file_getblock(unixfs, inumber,blockNo,buf);
if (bytesMoved < 0) {
return -1;
}
assert(bytesMoved > blockOffset);
openFileTable[fd].cursor += 1;
return (int)(buf[blockOffset]);
}
/*
* Return true if specified pathname is a regular file.
*/
int
Fileops_isfile(char *pathname)
{
numisfiles++;
int inumber = pathname_lookup(unixfs, pathname);
if (inumber < 0) {
return 0;
}
struct inode in;
int err = inode_iget(unixfs, inumber, &in);
if (err < 0) return 0;
if (!(in.i_mode & IALLOC) || ((in.i_mode & IFMT) != 0)) {
/* Not allocated or not a file */
return 0;
}
return 1; /* Must be a file */
}
/*
* Fetch the specified file block from the specified inode.
* Return the number of valid bytes in the block, -1 on error.
*/
int
file_getblock(struct unixfilesystem *fs, int inumber, int blockNum, void *buf)
{
//fprintf(stderr, "in file_getblock, size %d, inum: %d\n", cacheMemSizeInKB, inumber);
struct inode in;
int getResult = inode_iget(fs, inumber, &in);
int sectorNum = inode_indexlookup(fs, &in, blockNum);
int bytesRead = diskimg_readsector(fs->dfd, sectorNum, buf);
if ((getResult == -1) || (bytesRead == -1) || (sectorNum == -1)) return -1;
int size = inode_getsize(&in);
if ((size % BYTES_PER_BLOCK) == 0) {
return BYTES_PER_BLOCK;
} else {
int numblocks = (size / BYTES_PER_BLOCK);
if (blockNum == numblocks) {
return size % BYTES_PER_BLOCK;
} else {
return BYTES_PER_BLOCK;
}
}
}
/*
* Fetch the specified file block from the specified inode.
* Return the number of valid bytes in the block, -1 on error.
*/
int
file_getblock(struct unixfilesystem *fs, int inumber, int blockNum, void *buf)
{
// Consider inumber = 17, blocknumber = 5:
// – Find the inode
struct inode inp;
if(inode_iget(fs, inumber, &inp) < 0){
printf("Error getting inode %i\n", inumber);
return -1;
}
int filesize = inode_getsize(&inp);
int partial = (filesize % DISKIMG_SECTOR_SIZE == 0) ? 0 : 1;
int blocks = (filesize / DISKIMG_SECTOR_SIZE) + partial;
// – Find the sector number
int sectorNum = inode_indexlookup(fs, &inp, blockNum);
if(sectorNum == -1){
printf("Error getting data sector %i\n", blockNum);
return -1;
}
if((sectorNum > (int)fs->superblock.s_fsize) || (sectorNum < fs->superblock.s_isize + INODE_START_SECTOR)){
printf("sectorNum: %i blockNum: %i blocks: %i inode: %i\n", sectorNum, blockNum, blocks, inumber);
}
// – Read the data in the sector into the buffer
if (diskimg_readsector(fs->dfd, sectorNum, buf) != DISKIMG_SECTOR_SIZE) {
fprintf(stderr, "Error reading sector %i for block %i of %i\n", sectorNum, blockNum, blocks);
return -1;
}
//Determine value of valid bytes in the block
if(blockNum == blocks - 1){
if(partial) {
return (filesize % DISKIMG_SECTOR_SIZE);
}else{
return DISKIMG_SECTOR_SIZE;
}
}else{
return DISKIMG_SECTOR_SIZE;
}
}
/*
* Compute the checksum of a inumber. Assumes chksum arguments points to a
* CHKSUMFILE_SIZE byte array. Returns the length of the checksum, or -1 if
* it encounters an error.
*/
int
chksumfile_byinumber(struct unixfilesystem *fs, int inumber, void *chksum)
{
SHA_CTX shactx;
if (!SHA1_Init(&shactx)) {
// An error occurred initializing the SHA1 context.
return -1;
}
struct inode in;
int err = inode_iget(fs, inumber, &in);
if (err < 0) {
return err;
}
if (!(in.i_mode & IALLOC)) {
// The inode isn't allocated, so we can't hash it.
return -1;
}
int size = inode_getsize(&in);
for (int offset = 0; offset < size; offset += DISKIMG_SECTOR_SIZE) {
char buf[DISKIMG_SECTOR_SIZE];
int bno = offset/DISKIMG_SECTOR_SIZE;
int bytesMoved = file_getblock(fs, inumber, bno, buf);
if (bytesMoved < 0)
return -1;
if (!SHA1_Update(&shactx, buf, bytesMoved))
return -1;
}
if (!SHA1_Final(chksum, &shactx))
return -1;
return SHA_DIGEST_LENGTH;
}
/*
* Lookup the specified name (name) in the directory (dirinumber). If found, return the
* directory entry in dirEnt. Return 0 on success and something negative on failure.
*/
int
directory_findname(struct unixfilesystem *fs, const char *name,
int dirinumber, struct direntv6 *dirEnt)
{
struct inode directory;
if (inode_iget(fs, dirinumber, &directory)) return -1;
int mode = directory.i_mode;
//Checks that directory is indeed a directory.
if ((mode & IFMT) != IFDIR) return -1;
int dirSize = inode_getsize(&directory);
int dirBlocks = dirSize / DISKIMG_SECTOR_SIZE;
int check = 0;
for (int i=0; i <= dirBlocks; i++)
{
struct direntv6 filenames[DIRENTV6_IN_SECTOR];
int validBytes = file_getblock (fs, dirinumber, i, filenames);
int validFiles = validBytes / sizeof(struct direntv6);
check = search_for_filename(filenames, validFiles, name, dirEnt);
if(check) break;
}
return check-1;
}
/*
* Fetch the specified file block from the specified inode.
* Return the number of valid bytes in the block, -1 on error.
*/
int
file_getblock(struct unixfilesystem *fs, int inumber, int blockNum, void *buf)
{
//Find the inode
struct inode inp;
if(inode_iget(fs, inumber, &inp) < 0){
printf("Error getting inode %i\n", inumber);
return -1;
}
//Find the sector number for the blockNum
int sectorNum = inode_indexlookup(fs, &inp, blockNum);
if(sectorNum == -1){
printf("Error getting data sector %i\n", blockNum);
return -1;
}
//Read the data in the sector into the buffer
if (diskimg_readsector(fs->dfd, sectorNum, buf) != DISKIMG_SECTOR_SIZE) {
fprintf(stderr, "Error reading sector %i for block %i\n", sectorNum, blockNum);
return -1;
}
//Return number of valid bytes in the block
return validBytes(&inp, blockNum);
}
/*
* Lookup the specified name (name) in the directory (dirinumber). If found, return the
* directory entry in dirEnt. Return 0 on success and something negative on failure.
*/
int
directory_findname(struct unixfilesystem *fs, const char *name,
int dirinumber, struct direntv6 *dirEnt)
{
// Get the directory's inode
struct inode inp;
int success = inode_iget(fs, dirinumber, &inp);
// Return -1 on error
if (success == -1){
return -1;
}
// The dirinumber does not match to a directory
if ((inp.i_mode & IFMT) != IFDIR) {
return -1;
}
// The size of the directory
int size = inode_getsize(&inp);
// Total number of dirent's
int numDirEnts = size/ sizeof(struct direntv6);
// The number of dirEnt's in one block
int numDirEntsInBlock = DISKIMG_SECTOR_SIZE / sizeof(struct direntv6);
// The number of blocks the struct consistst of
int numBlocks = numDirEnts / numDirEntsInBlock;
// If the number of dirEnts don't fully occupy a block, add one
if(numDirEnts % numDirEntsInBlock !=0) numBlocks +=1;
// Look through all of the blocks in the inode
for(int block = 0; block < numBlocks; block++){
// Create a buffer
struct direntv6 dirEntTable[numDirEntsInBlock];
// Had &dirEntTable
success = file_getblock(fs,dirinumber,block,dirEntTable);
// Check for error
if (success < 0){
return -1;
}
// Look over all of the dirEnt's in a block
for(int d = 0; d < numDirEntsInBlock; d++){
struct direntv6 dir = dirEntTable[d];
// See if the strings match
if(strcmp(name,dir.d_name) == 0){
// Copy the dir into dirEnt and return
memcpy(dirEnt,&dir,sizeof(struct direntv6));
return 0;
}
}
}
// return -1 on no match
return -1;
}
/*
* Output to the specified file the checksum of the specified pathname and
* inode as well as all its children if it is a directory.
*
* This is used by the grading script, so be careful not to change its output
* format.
*/
void
DumpPathAndChildren(struct unixfilesystem *fs, const char *pathname, int inumber, FILE *f)
{
struct inode in;
if (inode_iget(fs, inumber, &in) < 0) {
fprintf(stderr,"Can't read inode %d \n", inumber);
return;
}
assert(in.i_mode & IALLOC);
char chksum1[CHKSUMFILE_SIZE];
if (chksumfile_byinumber(fs, inumber, chksum1) < 0) {
fprintf(stderr,"Can't checksum inode %d path %s\n", inumber, pathname);
return;
}
char chksum2[CHKSUMFILE_SIZE];
if (chksumfile_bypathname(fs, pathname, chksum2) < 0) {
fprintf(stderr,"Can't checksum inode %d path %s\n", inumber, pathname);
return;
}
if (!chksumfile_compare(chksum1, chksum2)) {
fprintf(stderr,"Pathname checksum of %s differs from inode %d\n", pathname, inumber);
return;
}
char chksumstring[CHKSUMFILE_STRINGSIZE];
chksumfile_cvt2string(chksum2, chksumstring);
int size = inode_getsize(&in);
fprintf(f, "Path %s %d mode 0x%x size %d checksum %s\n",pathname,inumber,in.i_mode, size, chksumstring);
if (pathname[1] == 0) {
/* pathame == "/" */
pathname++; /* Delete extra / character */
}
if ((in.i_mode & IFMT) == IFDIR) {
const unsigned int MAXPATH = 1024;
if (strlen(pathname) > MAXPATH-16) {
fprintf(stderr, "Too deep of directories %s\n", pathname);
}
struct direntv6 direntries[10000];
int numentries = GetDirEntries(fs, inumber, direntries, 10000);
for (int i = 0; i < numentries; i++) {
char *n;
n = direntries[i].d_name;
if (n[0] == '.') {
if ((n[1] == 0) || ((n[1] == '.') && (n[2] == 0))) {
/* Skip over "." and ".." */
continue;
}
}
char nextpath[MAXPATH];
sprintf(nextpath, "%s/%s",pathname, direntries[i].d_name);
DumpPathAndChildren(fs, nextpath, direntries[i].d_inumber, f);
}
}
}
/*
* add one entry to the directory initialized by entry name
* detail impletation is read the last block of the directory and add the item.
* it is kind of troublesome to consider the block shortage problem and others
*/
int directory_addItem(struct unixfilesystem *fs, const char *entryName,
int dirinumber, int FileType)
{
struct inode dirIn;
int err = inode_iget(fs, dirinumber, &dirIn);
if (err < 0) {
fprintf(stderr, "directory_addItem get dir inode failed\n");
return -1;
}
if (!(dirIn.i_mode & IALLOC) || ((dirIn.i_mode & IFMT) != IFDIR)) {
fprintf(stderr, "directory_addItem dir inode is not DIR or ALLOCATED");
return -1;
}
/*
* inode_size % DISKIMG_SECTOR_SIZE == 0
* means no space left in inode, so we need alloc a new block
*/
int inode_size = inode_getsize(&dirIn);
if (inode_size % DISKIMG_SECTOR_SIZE == 0)
{
err = filsys_allocBlocks(fs, &dirIn, 1);
if (err < 0) {
fprintf(stderr, "directory_addItem can't apply new blocks and inode_size = %d\n",inode_size);
}
}
/* increase dir's inode_size first to make the file_getblock works legal */
inode_setsize(&dirIn, inode_size + sizeof(struct direntv6));
inode_iwrite(fs, dirinumber, &dirIn); /* Save dir's inode_size first */
/* Read the last item of directory, change and write it back
because we handle the overflow problem in above code, so
just do the normal routine */
char buf[DISKIMG_SECTOR_SIZE];
{
/*
Read Last block of directory, because inode_size has increased before,
now the inode_size is the old one, but easy to compute if inode_size % DISKIMG_SECTOR_SIZE == 0
then inode_lastBlockNum = new allocated blockNum.
*/
int inode_lastBlockNum = inode_size / DISKIMG_SECTOR_SIZE;
struct direntv6 *dirEnt = (struct direntv6 *)buf;
//printf("directory i_mode = %d %d\n", in.i_mode, dirinumber);
file_getblock(fs, dirinumber, inode_lastBlockNum, buf); // last block is inode_BlockNum
/* locate the entry id */
int dirEnt_last = (inode_size % DISKIMG_SECTOR_SIZE) / sizeof(struct direntv6);
strcpy(dirEnt[dirEnt_last].d_name, entryName); // copy name
int inumber_new = filsys_allocInode(fs); // allocate an new inode and copy to dirEnt.
if (inumber_new < 0) {
fprintf(stderr, "directory_addItem can't apply new Inode");
}
dirEnt[dirEnt_last].d_inumber = inumber_new;
//printf("new allocated inumber = %d , entryName = %s, dir_bno = %d\n", inumber_new, entryName, inode_lastBlockNum);
/* initialize new inode and save */
struct inode in_new;
inode_iget(fs, inumber_new, &in_new);
inode_format(&in_new);
in_new.i_mode |= FileType; // set inode mode.
inode_iwrite(fs, inumber_new, &in_new); // save new allocated inode
/* write buf back to the block */
file_writeblock(fs, dirinumber, inode_lastBlockNum, buf);
}
inode_iwrite(fs, dirinumber, &dirIn); /* Save dir's inode */
return 0;
}
