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#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "disk.h"
#define MAX_INODES 10
#define INODE_START (TRACKS * SECTORS) / (8 * 512)
struct block_ptr {
char track;
short sector;
};
struct blockll{
struct block_ptr data;
struct blockll *next;
};
struct meta_data{
char name[8];
int size;
int read;
int write;
int create;
};
struct inode {
struct meta_data info;
struct block_ptr data[20];
};
typedef struct filestuff{
int fd;
struct inode file;
};
struct inode_list{
struct inode node;
struct inode_list *next;
}
int inode_list_size = 0;
struct inode_list *root;
char bitmap[128][4096/8];
int check_bitmap(t,s)
int t,s;
{
char tmp;
tmp = bitmap[t][s/8];
tmp &= (1 << (s % 8));
return (int) tmp;
}
void set_bitmap(t,s)
int t,s;
{
bitmap[t][s/8] |= (1 << (s % 8));
return;
}
void print_bitmap()
{
int i,j;
for(i = 0; i < 128; i++){
printf("\n%4d ", i);
for (j = 0; j < 4096/8; j++) {
printf("%02x", bitmap[i][j]);
if (j %31 == 0) {
printf("\n%4d ",i);
}
}
}
}
/* TODO
* Implement inode table as binary tree to speedup searches
*/
int search_inodes(name)
char *name;
{
int i;
for(i = 0; i < MAX_INODES; i++){
if(strcmp(name, i_table[i].info.name) == 0)
return i;
}
}
struct blockll* get_blocks(size)
int size;
{
int i, t, s;
struct blockll *root, *current = malloc(sizeof(struct blockll));
root = current;
for (i = 0; size > 0 && i < (4096 * 128); i++) {
t = i / 4096;
s = i % 4096;
printf("checkedmap%d\t%d: %d\n", t,s,check_bitmap(t,s));
if (!check_bitmap(t, s)) {
current->next = malloc(sizeof(struct blockll));
current = current->next;
current-> next = NULL;
current->data.track = (char) t;
current->data.sector = (short) s;
set_bitmap(t,s);
size-= 512;
}
}
return i <(4096 * 128) ? root : NULL;
}
int inode_init()
{
int n = MAX_INODES / 4;
int i;
char *ptr;
struct inode_list tmp;
if (MAX_INODES % 4 > 0)
n++;
char *buf = malloc(512 * n);
for (i =0; i < n; i++) {
rsector(0, i, buf + (512 * i));
}
ptr = buf;
tmp = root;
for(i=0; i< MAX_INODES; i++) {
tmp->next = malloc(sizeof(struct inode_list));
memcpy(&tmp->node, ptr, 64);
ptr += 64;
tmp = tmp->next
inode_list_size++;
}
}
/*save inodes to first n sectors on disk*/
void inode_save()
{
int i, j;
char *buf = malloc(512);
struct inode_list tmp = root;
for (i = 0; i < MAX_INODES && tmp->next;i++) {
for (j = 0; j < 4; j++){
tmp = tmp->next;
memcpy(buf + j, tmp->node, sizeof(struct inode));
}
wsector(0, INODE_START + i, buf);
}
}
int open(fname, mode)
char *fname, *mode;
{
}
int close(fd)
int fd;
{
}
int read(fd, buf)
int fd;
char *buf;
{
}
int write(fd, buf)
int fd;
char *buf;
{
}
int ulink(fname)
char *fname;
{
}
int main()
{
inode_init();
inode_save();
}
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