long get_start_address(cs1550_directory_entry directory, int file_index) //gives the new start address(if needed) of file
{
long count = 0;
long start_address = directory.files[ file_index ].nStartBlock; //holds the start address of the file
long error_checker_address = start_address;
while( count <= directory.files[ file_index ].fsize )
{
int check = is_next_block_free(start_address);
if(check != 0) //next block is free
{
count+= 512; //add a block size for every iteration
}
else
{
start_address = find_next_free_block(start_address); //finds next free block and sets block_start to that address
if(error_checker_address == start_address) //signalfies out of mememory
{
perror("OUT OF MEMORY!!\n"); //out of memeory
break;
}
count = 0; //reset count
}
}
return start_address; //returns the new start address
}
uint8_t* ramdisk_init(){
int i;
uint8_t* ramdisk;
int root_bid;
struct rd_inode* root_inode;
struct rd_super_block* InitSuperBlock;
#ifdef UL_DEBUG
if(!(ramdisk=(uint8_t*)malloc(RAMDISK_SIZE*sizeof(uint8_t)))){
fprintf(stderr,"No sufficient mem space for ramdisk!\n");
exit(-1);
}
#endif
#ifndef UL_DEBUG
if(!(ramdisk=(uint8_t*)vmalloc(RAMDISK_SIZE*sizeof(uint8_t)))){
printk("<1> No sufficient mem space for ramdisk!\n");
return NULL;
}
#endif
//Nullify all the data in ramdisk
memset(ramdisk,0,RAMDISK_SIZE);
//Init the bitmap
for(i=0;i<=(BITMAP_LIMIT+1)/RD_BLOCK_SIZE;i++){
set_bitmap(ramdisk,i);
}
//Init the root directory
root_bid=find_next_free_block(ramdisk);//BlockNO for root dir
#ifdef UL_DEBUG
if(!(root_inode=(struct rd_inode*)malloc(sizeof(struct rd_inode)))){
fprintf(stderr, "No sufficient mem space for root dir!\n");
exit(-1);
}
#endif
#ifndef UL_DEBUG
if(!(root_inode=(struct rd_inode*)vmalloc(sizeof(struct rd_inode)))){
printk("<1> No sufficient mem space for root dir!\n");
return NULL;
}
#endif
root_inode->type=0;
root_inode->size=0;
root_inode->BlockPointer[0]=root_bid;
update_inode(ramdisk,0,root_inode);
//Init the superblock
#ifdef UL_DEBUG
if(!(InitSuperBlock=(struct rd_super_block*)malloc(sizeof(struct rd_super_block)))){
fprintf(stderr,"No sufficient mem\n");
exit(-1);
}
#endif
#ifndef UL_DEBUG
if(!(InitSuperBlock=(struct rd_super_block*)vmalloc(sizeof(struct rd_super_block)))){
printk("<1> No sufficient mem\n");
return NULL;
}
#endif
InitSuperBlock->FreeBlockNum=BLOCK_NUM-(BITMAP_LIMIT+1)/RD_BLOCK_SIZE;
InitSuperBlock->FreeInodeNum=INODE_NUM-1;//The root dir takes one inode
memset(InitSuperBlock->InodeBitmap,0,INODEBITMAP_SIZE);
update_superblock(ramdisk,InitSuperBlock);
//Init the inode bitmap in superblock
set_inode_bitmap(ramdisk,0);
#ifndef UL_DEBUG
vfree(root_inode);
#endif
return ramdisk;
}
void
create_new_file(ProDisk *disk, int dir_block, int storage_type, char *name,
int file_type, word32 creation_time, int version, int min_version,
int access, int aux_type, word32 last_mod, word32 eof)
{
Vol_hdr *vol_ptr;
int val;
Directory *dir_ptr;
File_entry *file_ptr;
int file_count;
int pos;
int last_pos;
int done;
int next_blk;
int name_len;
name_len = strlen(name);
dir_ptr = disk_read_dir(disk, dir_block);
next_blk = dir_block;
val = dir_ptr->file_entries[0].storage_type_name_len;
last_pos = 13;
pos = 0;
if(((val & 0xf0) == 0xf0) || ((val & 0xf0) == 0xe0)) {
/* vol dir or subdir header */
vol_ptr = (Vol_hdr *)&(dir_ptr->file_entries[0]);
file_count = get_l2byte(&(vol_ptr->file_count));
pos = 1;
last_pos = vol_ptr->entries_per_block;
} else {
printf("dir_block: %04x not subdir or voldir\n", dir_block);
exit(6);
}
vol_ptr = 0;
done = 0;
while(!done) {
file_ptr = &(dir_ptr->file_entries[pos]);
if(((file_ptr->storage_type_name_len) & 0xf0) == 0) {
/* Got it! */
file_ptr->storage_type_name_len =
(storage_type << 4) | name_len;
strncpy((char *)file_ptr->file_name, name, 15);
file_ptr->file_type = file_type;
set_l2byte(&(file_ptr->key_pointer),
find_next_free_block(disk));
set_l2byte(&(file_ptr->blocks_used), 0);
set_pro_time(&(file_ptr->creation_time),
creation_time);
file_ptr->version = version;
file_ptr->min_version = min_version;
file_ptr->access = access;
set_l2byte(&(file_ptr->aux_type), aux_type);
set_pro_time(&(file_ptr->last_mod), last_mod);
set_l2byte(&(file_ptr->header_pointer),
dir_block);
set_l3byte(&(file_ptr->eof), eof);
disk_write_dir(disk, next_blk);
dir_ptr = disk_read_dir(disk, dir_block);
vol_ptr = (Vol_hdr *)&(dir_ptr->file_entries[0]);
set_l2byte(&(vol_ptr->file_count), file_count+1);
disk_write_dir(disk, dir_block);
disk_read_dir(disk, next_blk);
/* re-read dir so that ptrs are set up right */
disk->file_ptr = file_ptr;
disk->file_open = 1;
disk->ind_blk_num = -1;
disk->master_ind_blk_num = -1;
done = 1;
break;
} else {
/* check to make sure name is unique */
if((file_ptr->storage_type_name_len & 0x0f)== name_len){
if(!memcmp(file_ptr->file_name, name,name_len)){
printf("Name %s already on disk!\n",
name);
exit(8);
}
}
pos++;
if(pos >= last_pos) {
/* Go to next block */
next_blk = get_l2byte(&(dir_ptr->next_blk));
if(next_blk) {
dir_ptr = disk_read_dir(disk, next_blk);
pos = 0;
} else {
printf("Top directory full!\n");
exit(2);
}
}
}
}
}
