static int gfs_zero_inode(struct gfs_inode_info *inode)
{
struct gfs_super_info *sb = (struct gfs_super_info *)inode->vfs_inode.i_sb->s_fs_info;
int nblocks = sb->s_chunk_size, i;
for( i = 0;i<nblocks; ++i ) {
struct buffer_head *bh = get_inode_block(inode, i, 1);
if(!bh)
return -ENOMEM;
memset(bh->b_data, 0, bh->b_size);
put_inode_block(inode,1);
}
return 0;
}
int create_file(char *path, int is_dir)
{
char *lpath = malloc(sizeof(char)*strlen(path)+1);
char *last;
char *ptr;
int wd, free_inode_num, found, s;
struct inode_block *cur_inode_block = NULL;
struct inode *cur_inode = NULL;
strcpy(lpath, path);
if(strlen(lpath) == 1)
{
if(lpath[0] == '/')
{
return ERR_FILE_EXISTS;
}
else
{
return ERR_INVALID_PATH;
}
}
ptr = strrchr(lpath, '/');
if(ptr == lpath+strlen(lpath)-1)
{
*ptr = '\0';
ptr = strrchr(lpath, '/');
}
*ptr = '\0';
ptr++;
last = malloc(sizeof(char)*strlen(ptr)+1);
strcpy(last, ptr);
wd = path_to_inode(lpath);
DEBUG1 && printf("wd = %d \n", wd);
if(wd < 0)
{
return ERR_INVALID_PATH;
}
//printf("wd inode = %d \n", wd);
get_inode(&cur_inode_block, &cur_inode, wd);
if(cur_inode_block == NULL || cur_inode == NULL)
{
DEBUG2 && printf("get inode failed\n");
return ERR_INTERNAL;
}
found = has_file(cur_inode, last);
//printf("found = %d \n", found);
DEBUG1 && printf("found = %d \n", found);
if(found != -1)
{
//printf("file or dir already exists!\n");
//printf("wd = %d, last = %s \n ", wd, last);
return ERR_FILE_EXISTS;
}
free_inode_num = get_free_inode();
//printf("free inode num = %d\n", free_inode_num);
if(free_inode_num < 0)
{
return ERR_MAX_FILES;
}
get_inode( &cur_inode_block, &cur_inode , free_inode_num);
if(cur_inode_block == NULL || cur_inode == NULL)
{
return ERR_INTERNAL;
}
cur_inode->is_dir = is_dir;
put_inode_block(cur_inode_block, free_inode_num);
//free_data_block_num = get_free_datablock();
//printf("free_data_block_num = %d\n", free_data_block_num);
s = add_dir_to_inode(wd, last, free_inode_num);
return s;
}
int add_data_block(int inode_num)
{
struct datablock *dblock = malloc(sizeof(struct datablock));
struct indirection_block *iblock1;
struct indirection_block *iblock2;
struct inode_block *iblock;
struct inode *inode;
int block_num;
int new_db_num = get_free_datablock();
DEBUG1 && printf("new db number: %d \n", new_db_num);
if(new_db_num < 0)
return -1;
get_inode(&iblock, &inode, inode_num);
block_num = inode->num_blocks;
if(!inode)
{
DEBUG2 && printf("inode is null\n");
return -1;
}
if(block_num >= 0 && block_num < 10)
{
inode->file_blocks[block_num] = new_db_num;
inode->num_blocks++;
if(put_inode_block(iblock, inode_num))
{
return -1;
}
free(iblock);
return new_db_num;
}
else if(block_num == 10)
{
//make indirection block
struct indirection_block *ib = malloc(sizeof(struct indirection_block));
ib->pointer[0] = new_db_num;
int ind_block_num = get_free_datablock();
if(ind_block_num < 0)
return -1;
DEBUG1 && printf("adding indirection block: %d\n", ind_block_num);
if(!write_block(file, ib, ind_block_num))
{
DEBUG2 && printf("Error writing indirection block\n");
return -1;
}
inode->indirect1 = ind_block_num;
inode->num_blocks++;
if(put_inode_block(iblock, inode_num))
{
return -1;
}
free(ib);
free(iblock);
return new_db_num;
}
else if(block_num > 10 && block_num < (10+128))
{
struct indirection_block *ib = malloc(sizeof(struct indirection_block));
int ind_block_num = inode->indirect1;
if(!read_block(file, ib, ind_block_num))
{
DEBUG2 && printf("Error reading indirection block\n");
return -1;
}
ib->pointer[block_num - 10] = new_db_num;
if(! write_block(file, ib, ind_block_num))
{
DEBUG2 && printf("Error writing indirection block\n");
return -1;
}
inode->num_blocks++;
if(put_inode_block(iblock, inode_num))
{
return -1;
}
free(ib);
free(iblock);
return new_db_num;
}
else if(block_num == (10+128))
{
struct indirection_block *ib1 = malloc(sizeof(struct indirection_block));
struct indirection_block *ib2 = malloc(sizeof(struct indirection_block));
int ind_block_num1 = get_free_datablock();
int ind_block_num2 = get_free_datablock();
if(ind_block_num1 < 0 || ind_block_num2 < 0)
return -1;
inode->indirect2 = ind_block_num1;
inode->num_blocks++;
ib1->pointer[0] = ind_block_num2;
ib2->pointer[0] = new_db_num;
if(!write_block(file, ib1, ind_block_num1))
{
DEBUG2 && printf("Error writing indirection block\n");
return -1;
}
if(!write_block(file, ib2, ind_block_num2))
{
DEBUG2 && printf("Error writing indirection block\n");
return -1;
}
if(put_inode_block(iblock, inode_num))
{
return -1;
}
free(ib1);
free(ib2);
free(iblock);
return new_db_num;
}
else if(block_num > (10+128) && block_num < (10+128+(128*128)))
{
struct indirection_block *ib1 = malloc(sizeof(struct indirection_block));
struct indirection_block *ib2 = malloc(sizeof(struct indirection_block));
int ind_block_num1 = inode->indirect2;
if( !read_block(file, ib1, ind_block_num1))
{
DEBUG2 && printf("error reading datablock\n");
return -1;
}
if(((block_num - (10+128)) % 128) == 0)
{
int new_ind_block = get_free_datablock();
ib1->pointer[(block_num - (10+128)) / 128] = new_ind_block;
ib2->pointer[0] = new_db_num;
inode->num_blocks++;
if(!write_block(file, ib1, ind_block_num1))
{
DEBUG2 && printf("error reading datablock\n");
return -1;
}
if(!write_block(file, ib2, new_ind_block))
{
DEBUG2 && printf("error reading datablock\n");
return -1;
}
if(put_inode_block(iblock, inode_num))
{
return -1;
}
return new_db_num;
}
else
{
int ind_block_num2 = ib1->pointer[(block_num - (10+128)) / 128];
if(!read_block(file, ib2, ind_block_num2))
{
DEBUG2 && printf("error reading datablock\n");
return -1;
}
ib2->pointer[(block_num - (10+128)) % 128] = new_db_num;
inode->num_blocks++;
if( !write_block(file, ib2, ind_block_num2))
{
DEBUG2 && printf("error reading datablock\n");
return -1;
}
if(put_inode_block(iblock, inode_num))
{
return -1;
}
return new_db_num;
}
}
else
{
DEBUG2 && printf("Error: cannot add another block, filesize max reached\n");
return -1;
}
return new_db_num;
}
//find free inode, remove from free inode list, return inode number
int get_free_inode(void)
{
struct superblock *sb = malloc(sizeof(struct superblock));
struct inode_block *iblock;
struct inode *inode;
int inode_num;
int new_free;
int i;
if(! read_block(file, sb, 1))
{
DEBUG2 && printf("Error reading superblock\n");
return -1;
}
if( (inode_num = sb->free_inode_list) == -1)
{
DEBUG2 && printf("Error no free inodes\n");
return -1;
}
if(get_inode(&iblock, &inode, inode_num))
{
DEBUG2 && printf("ERROR: couldn't get inode \n ");
return -1;
}
new_free = inode->next_free_inode;
inode->next_free_inode = -2;
inode->is_free=0;
inode->num_blocks=0;
inode->is_dir=0;
for(i=0; i < 10 ; i++)
{
inode->file_blocks[i] = 0;
}
inode->indirect1 = 0;
inode->indirect2 = 0;
DEBUG1 && printf("new_free: %d \n", new_free);
sb->free_inode_list = new_free;
sb->files_allocated++;
if(! write_block(file, sb, 1))
{
DEBUG2 && printf("Error writing superblock\n");
return -1;
}
if(put_inode_block(iblock, inode_num))
{
return -1;
}
free(sb);
free(iblock);
return inode_num;
}
int delete_file(char *path)
{
char *lpath = malloc(sizeof(char)*strlen(path)+1);
char *orig_path = malloc(sizeof(char)*strlen(path)+1);
char *last;
char *ptr;
char null_array[12];
int wd, free_inode_num, found, s;
int inode_num;
struct inode_block *ib = NULL;
struct inode *inode = NULL;
struct inode_block *doomed_ib = NULL;
struct inode *doomed_inode = NULL;
struct directory *dir = NULL;
struct datablock *datablock = NULL;
struct directory *ldir = NULL;
struct datablock *ldatablock = NULL;
int doomed_inode_num;
int i, j, k, foundit = 0;
int cur_db_num, last_db_num;
/*
for(i=0;i<12;i++){
null_array[i] = '\0';
}
*/
strcpy(lpath, path);
strcpy(orig_path, path);
if(strlen(lpath) == 1)
{
if(lpath[0] == '/')
{
return ERR_FILE_EXISTS; //update this to correct val
}
else
{
return ERR_INVALID_PATH;
}
}
ptr = strrchr(lpath, '/');
if(ptr == lpath+strlen(lpath)-1)
{
*ptr = '\0';
ptr = strrchr(lpath, '/');
}
ptr++;
last = malloc(sizeof(char)*strlen(ptr)+1);
strcpy(last, ptr);
*ptr = '\0';
wd = path_to_inode(lpath);
DEBUG1 && printf("lpath = %s last = %s \n", lpath, last);
//funct to remove all data blocks
if((doomed_inode_num = path_to_inode(orig_path)) < 0)
{
DEBUG1 && printf("cannot delete, does not exist\n");
return ERR_FILE_NOT_FOUND;
}
if((get_inode(&doomed_ib, &doomed_inode, doomed_inode_num)) < 0)
{
DEBUG2 && printf("error get_inode\n");
return -1;
}
if(doomed_inode->is_dir != 0 && doomed_inode->num_blocks > 0)
{
DEBUG1 && printf("cannot delete a none empty directory");
return ERR_INVALID_PATH;//should be a different error
}
erase_inode(doomed_inode_num);
//funct to remove from dir
if((inode_num = path_to_inode(lpath)) < 0)
{
DEBUG2 && printf("error path_to_inode\n");
return -1;
}
if((get_inode(&ib, &inode, inode_num)) < 0)
{
DEBUG2 && printf("error get_inode\n");
return -1;
}
for(i=0; i<inode->num_blocks; i++)
{
cur_db_num = get_data_block(&datablock, inode, i);
dir = (struct directory *)datablock;
for(j=0; j<32; j++)
{
if(strcmp(last,dir->entries[j].filename) == 0 )
{
DEBUG1 && printf("got it!\n");
//strcpy(dir->entries[j].filename, "");
//dir->entries[j].inode_number = 0;
foundit = 1;
//write_block(file, dir, cur_db_num);
break;
}
}
if(foundit)
{
break;
}
}
if(!foundit)
{
return -1;
}
last_db_num = get_data_block(&ldatablock, inode, inode->num_blocks-1);
ldir = (struct directory *)ldatablock;
if(last_db_num == cur_db_num)
{
for(k=0; k<32; k++)
{
if(dir->entries[k].inode_number == 0)
{
//k++;
break;
}
}
// k-1 is the one we want, even if we went all the way to the end.
strcpy(dir->entries[j].filename, dir->entries[k-1].filename);
dir->entries[j].inode_number = dir->entries[k-1].inode_number;
for(i=0; i<12; i++)
{
dir->entries[k-1].filename[i] = '\0';
}
dir->entries[k-1].inode_number = 0;
write_block(file, dir, cur_db_num);
if(k-1 == 0)
{
//add last_db_num to free blocks
if(make_free_datablock(last_db_num))
{
DEBUG2 && printf("couldnt free datablock\n");
}
//subtract a datablock from inode->num_blocks
//WE NEED TO ADD STUFF TO SUBTRACT INDIRECTION BLOCKS
inode->num_blocks--;
DEBUG1 && printf("inode->num_blocks = %d \n", inode->num_blocks);
//write the inode back
put_inode_block(ib, inode_num);
trim_indirection_blocks(inode_num);
}
}
else
{
for(k=0; k<32; k++)
{
if(ldir->entries[k].inode_number == 0)
{
//k++;
break;
}
}
// k-1 is the one we want, even if we went all the way to the end.
strcpy(dir->entries[j].filename, ldir->entries[k-1].filename);
dir->entries[j].inode_number = ldir->entries[k-1].inode_number;
for(i=0; i<12; i++)
{
ldir->entries[k-1].filename[i] = '\0';
}
ldir->entries[k-1].inode_number = 0;
write_block(file, dir, cur_db_num);
write_block(file, ldir, last_db_num);
if(k-1 == 0)
{
//add last_db_num to free blocks
if(make_free_datablock(last_db_num))
{
DEBUG1 && printf("couldnt free datablock\n");
}
//subtract a datablock from inode->num_blocks
//WE NEED TO ADD STUFF TO SUBTRACT INDIRECTION BLOCKS
inode->num_blocks--;
DEBUG1 && printf("inode->num_blocks = %d \n", inode->num_blocks);
//write the inode back
put_inode_block(ib, inode_num);
trim_indirection_blocks(inode_num);
}
}
return SUCCESS;
}
int trim_indirection_blocks(int inode_num)
{
struct inode_block *ib = NULL;
struct inode *inode = NULL;
struct indirection_block *idb = malloc(sizeof(struct indirection_block));
int num_blocks;
if((get_inode(&ib, &inode, inode_num)) < 0)
{
DEBUG2 && printf("error get_inode\n");
return -1;
}
num_blocks = inode->num_blocks;
if(num_blocks < 10 && inode->indirect1 != 0)
{
//remove inode->indirect1
make_free_datablock(inode->indirect1);
inode->indirect1 = 0;
put_inode_block(ib, inode_num);
return 1;
}
if(num_blocks < (10+128) && inode->indirect2 != 0)
{
//remove inode->indirect2
make_free_datablock(inode->indirect2);
inode->indirect2 = 0;
put_inode_block(ib, inode_num);
return 1;
}
if(num_blocks >= (10+128) && num_blocks < (10+128+(128*128)))
{
if(((num_blocks - (10+128)) % 128) == 0)
{
//remove second level indirection block
if(!read_block(file, idb, inode->indirect2))
{
DEBUG2 && printf("Error reading indirection block\n");
return -1;
}
if( idb->pointer[(num_blocks - (10+128)) / 128] != 0)
{
make_free_datablock(idb->pointer[(num_blocks - (10+128)) / 128]);
idb->pointer[(num_blocks - (10+128)) / 128] = 0;
return 1;
}
//block to remove
//ib1->pointer[(block_num - (10+128)) / 128]
//int new_ind_block = get_free_datablock();
//ib1->pointer[(block_num - (10+128)) / 128]
//ib2->pointer[0] = new_db_num;
//inode->num_blocks++;
}
}
return 0;
}
int erase_inode(int inode_num)
{
struct inode_block *ib = NULL;
struct inode *inode = NULL;
struct directory *dir = NULL;
struct datablock *datablock = NULL;
struct indirection_block *idb = malloc(sizeof(struct indirection_block));
struct indirection_block *idb2 = malloc(sizeof(struct indirection_block));
struct superblock *sb = malloc(sizeof(struct superblock));
int cur_db_num, i;
if((get_inode(&ib, &inode, inode_num)) < 0)
{
DEBUG2 && printf("error get_inode\n");
return -1;
}
while(inode->num_blocks > 0)
{
cur_db_num = get_data_block(&datablock, inode, inode->num_blocks-1);
make_free_datablock(cur_db_num);
inode->num_blocks--;
}
if(inode->indirect1 != 0)
{
make_free_datablock(inode->indirect1);
inode->indirect1 = 0;
}
if(inode->indirect2 !=0)
{
if(!read_block(file, idb2, inode->indirect2))
{
return ERR_INTERNAL;
}
for(i=0; i<128; i++)
{
if(idb2->pointer[i] != 0)
{
make_free_datablock(idb2->pointer[i]);
}
}
make_free_datablock(inode->indirect2);
inode->indirect2 = 0;
}
for(i=0; i<10; i++)
{
inode->file_blocks[i] = 0;
}
inode->is_dir = 0;
inode->is_free = 1;
if(!read_block(file, sb, 1))
{
return ERR_INTERNAL;
}
inode->next_free_inode = sb->free_inode_list;
sb->free_inode_list = inode_num;
if(!write_block(file, sb, 1))
{
return ERR_INTERNAL;
}
put_inode_block(ib, inode_num);
}