/*
* Initialize: return -1 on error, 0 on success.
*/
int mm_init(void)
{
if ((heap_list_head = mem_sbrk(2 * HEADER_SIZE + 20*DSIZE)) == NULL )
return -1;
PUT(heap_list_head, 0); //Alignment padding
/*initialize dummy block header*/
PUT(heap_list_head + WSIZE, PACK(HEADER_SIZE, 1)); //WSIZE = padding
PUT(heap_list_head + DSIZE, 0); //pointer to next free block
PUT(heap_list_head + DSIZE+WSIZE, 0); //pointer to the previous free block
free_list_head = heap_list_head + 2*DSIZE + WSIZE;
/*initialize dummy block footer*/
PUT(heap_list_head + HEADER_SIZE, PACK(HEADER_SIZE, 1));
/*initialize epilogue*/
PUT(heap_list_head+WSIZE + HEADER_SIZE, PACK(0, 1));
/*initialize the free list pointer to the tail block*/
heap_list_head += DSIZE;
heap_header = heap_list_head;
init_free_list(heap_list_head);
/*return -1 if unable to get heap space*/
if ((heap_list_head = extend_heap(CHUNKSIZE / WSIZE)) == NULL )
return -1;
return 0;
}
/*
* Initialize: return -1 on error, 0 on success.
*/
int mm_init(void) {
/* Create the initial empty heap */
if ((heap_listp = mem_sbrk(WSIZE + SEG_LEVLL * DSIZE)) == (void *)-1)
return -1;
flist_tbl = heap_listp;
init_free_list();
int table_off = 2 * SEG_LEVLL * WSIZE;
PUT(heap_listp + table_off, PACK(4, 1)); /* Prologue header */
PUT(heap_listp + table_off + 4, PACK(0, 1)); /* Epilogue header */
FLAG(heap_listp + table_off);
FLAG(heap_listp + table_off + 4); /* set the alloc FLAG in next block */
heap_listp += table_off + 4;
/* Extend the empty heap with a free block of CHUNKSIZE bytes */
char *freeb = extend_heap(CHUNKSIZE/WSIZE);
if (freeb == NULL) {
return -1;
}
return 0;
}
void mksfs(int fresh){
//Implement mksfs here
if (fresh == 1){
//deletes fs if it already exists
if(access(DISK_FILE, F_OK) != -1){
unlink(DISK_FILE);
}
//fs creation
printf("Initalizing sfs\n");
init_fresh_disk(DISK_FILE, BLOCK_SIZE, MAX_BLOCKS);
//zero_everything();
// writes superblock to the first block
printf("Writing superblocks\n");
init_superblock();
write_blocks(0, 1, &sb);
// write the inode table to the 2nd block
printf("Writing inode table\n");
init_inode_table();
//add_root_dir_inode();
//add_dummy_file_inode();
//write_blocks(1, 1, &inode_table);
// creates free list
init_free_list();
// write root directory data to the 3rd block
printf("Writing root dir\n");
init_root_dir();
//allocate memory for directory inode
inode_t *inode = malloc(ADJUST((MAX_FILES+1)*sizeof(inode_t)));
read_blocks(INODE_TABLE, INODE_TABLE_SIZE, inode);
if(inode == NULL){
return;
}
//set first inode to point to directory
inode[0].size = DIRECTORY_SIZE*BLOCK_SIZE;
inode[0].link_cnt = DIRECTORY_SIZE;
inode[0].exists = 1;
//check to see if we need to use ref_ptr
//if(DIRECTORY_SIZE > 12){
//inode[0].ref_ptr = search();
//setAlloc(inode[0].ref_ptr);
//unsigned int *buffer = malloc(BLOCK_SIZE);
//write_blocks(19 + inode[0].ref_ptr, 1, buffer);
//free(buffer);
//assign the pointers the location of directory files
int i;
for(i = 0; i < DIRECTORY_SIZE; i++){
if(i > 11){
unsigned int *buffer = malloc(BLOCK_SIZE);
read_blocks(19+ inode[0].ref_ptr, 1, buffer);
buffer[i - 12] = 2 + i;
write_blocks(19+ inode[0].ref_ptr, 1, buffer);
free(buffer);
}
else{
inode[0].data_ptrs[i] = 2 + i;
}
}
//update inode and free memory
write_blocks(INODE_TABLE, INODE_TABLE_SIZE, inode);
free(inode);
}
else if (fresh == 0){
if(init_disk(DISK_FILE, BLOCK_SIZE, MAX_BLOCKS) != 0){
printf("Error initializing disk\n");
return;
}
}
//allocate main memory for filesystem data structures
int *superblock = malloc(BLOCK_SIZE*SUPERBLOCK_SIZE);
if(superblock == NULL){
printf("Error allocating memory for superblock\n");
return;
}
read_blocks(0, SUPERBLOCK_SIZE, superblock);
//allocate main memory for directory
root_dir = malloc(ADJUST(sizeof(dir_entry_t)*MAX_FILES));
if(root_dir == NULL){
printf("Error allocating memory for root directory\n");
return;
}
read_blocks(2, DIRECTORY_SIZE, root_dir);
//allocate memory for inode table
inode_table = malloc(ADJUST(sizeof(inode_t)*(MAX_FILES+1)));
if(inode_table == NULL){
printf("Error allocating memory for inode table");
return;
}
read_blocks(INODE_TABLE, INODE_TABLE_SIZE, inode_table);
fileCount = 0;
fd_table = NULL;
return;
}
