/*
* traverse root - taken from dos files. modified collectively
* recursively follows directories from the root checking each file
* for consistency as it goes
*/
void traverse_root(uint8_t *image_buf, struct bpb33* bpb) {
uint16_t cluster = 0;
struct direntry* dirent = (struct direntry*)
cluster_to_addr(cluster, image_buf, bpb);
char buffer [MAXFILENAME]; //buffer for storing file names
int i;
for (i = 0; i < bpb->bpbRootDirEnts; i++) {
uint16_t followclust = get_dirent(dirent, buffer);
// deal with normal files
if (dirent->deAttributes == ATTR_NORMAL) {
chkerr(dirent, buffer, image_buf, bpb);
}
append_clusters(followclust); // append file cluster
if (is_valid_cluster(followclust, bpb)) {
append_clusters(followclust);
follow_dir(followclust, 1, image_buf, bpb);
}
dirent++;
}
}
/*
* follow dir recursively scans through the file hierarchy
* we check for consistency for every directory entry
* taken from dos with some modifications.
*/
void follow_dir(uint16_t cluster, int indent,
uint8_t *image_buf, struct bpb33* bpb) {
while (is_valid_cluster(cluster, bpb)) {
append_clusters(cluster);
struct direntry *dirent = (struct direntry*)
cluster_to_addr(cluster, image_buf, bpb);
int numDirEntries = (bpb->bpbBytesPerSec * bpb->bpbSecPerClust)
/ sizeof(struct direntry);
char buffer[MAXFILENAME];
int i = 0;
for ( ; i < numDirEntries; i++) {
append_clusters(cluster);
uint16_t followclust = get_dirent(dirent, buffer);
chkerr(dirent, buffer, image_buf, bpb);
if (followclust) {
follow_dir(followclust, indent+1, image_buf, bpb);
}
dirent++;
}
cluster = get_fat_entry(cluster, image_buf, bpb);
}
}
void checkandfix(uint8_t *image_buf, struct bpb33* bpb, int *refcount)
{
uint16_t cluster = 0;
struct direntry *dirent = (struct direntry*)cluster_to_addr(cluster, image_buf, bpb);
int i = 0;
for ( ; i < bpb->bpbRootDirEnts; i++)
{
//to print directory use print_dirent (change to get_dirent when done)
uint16_t followclust = print_dirent(dirent, 0, image_buf, bpb, refcount);
//char buffer[MAXFILENAME];
//uint16_t followclust = get_dirent(dirent, buffer);
if (is_valid_cluster(followclust, bpb))
{
refcount[followclust]++; //updating refcount for index of current cluster
printf("refcount is: %d, followclust is: %d\n\n", refcount[followclust], followclust);
follow_dir(followclust, 1, image_buf, bpb, refcount);
}
//this is where the magic happens...or in print_dirent? I'd rather do
// it here
dirent++;
}
}
/************FOLLOW_DIR***************/
void follow_dir(uint16_t cluster, int indent, uint8_t *image_buf, struct bpb33* bpb, int* refcount)
{
while (is_valid_cluster(cluster, bpb))
{
struct direntry *dirent = (struct direntry*)cluster_to_addr(cluster, image_buf, bpb);
int numDirEntries = (bpb->bpbBytesPerSec * bpb->bpbSecPerClust) / sizeof(struct direntry); //can't we just use int numDirEntries = bpb->RootDirEnts??
int i = 0;
for ( ; i < numDirEntries; i++)
{
// char buffer[MAXFILENAME];
// uint16_t followclust = get_dirent(dirent, buffer);
uint16_t followclust = print_dirent(dirent, indent, image_buf, bpb, refcount); //changed to print as follow_dir is called
if (followclust)
{
refcount[followclust]++;
follow_dir(followclust, indent+1, image_buf, bpb, refcount);
}
dirent++;
}
cluster = get_fat_entry(cluster, image_buf, bpb);
}
}
void follow_dir(char* filename, uint16_t cluster, int indent,
uint8_t *image_buf, struct bpb33* bpb)
{
while (is_valid_cluster(cluster, bpb))
{
struct direntry *dirent = (struct direntry*)cluster_to_addr(cluster, image_buf, bpb);
int numDirEntries = (bpb->bpbBytesPerSec * bpb->bpbSecPerClust) / sizeof(struct direntry);
for ( int i=0; i < numDirEntries; i++)
{
uint16_t followclust = print_dirent(filename, dirent, indent);
int count = -1;
if (followclust!= 0) {
count=compare(filename, followclust,dirent,image_buf,bpb);
}
else {
}
//printf("count: %i\n", count);
if (followclust !=0)
follow_dir(filename, followclust, indent+1, image_buf, bpb);
dirent++;
}
cluster = get_fat_entry(cluster, image_buf, bpb);
}
}
/***********SAVE_ORPHANS***************/
void orphan_search(uint8_t *image_buf, struct bpb33* bpb, int * refcount, int FATsz) {
int count = 0; //count orphans
int i = 2;
for(; i < FATsz; i++)
{
uint16_t cluster = get_fat_entry(i, image_buf, bpb);
if(cluster != (FAT12_MASK & CLUST_FREE) && cluster != (FAT12_MASK & CLUST_BAD) && refcount[i] == 0)
{
printf("FOUND AN ORPHAN, CLUSTER # = %d\n", i);
count++;
int orphan_size = 1;
refcount[i] = 1;
uint16_t orphan_cluster = cluster;
while(is_valid_cluster(orphan_cluster, bpb))
{
if (refcount[orphan_cluster] == 1)
{
set_fat_entry(orphan_cluster, (FAT12_MASK & CLUST_EOFS), image_buf, bpb);
}
else if(refcount[orphan_cluster] > 1)
{
struct direntry *dirent = (struct direntry*)cluster_to_addr(cluster, image_buf, bpb);
dirent->deName[0] = SLOT_DELETED;
refcount[orphan_cluster]--;
printf("DELETED\n");
}
else if(refcount[orphan_cluster] < 1)
{
refcount[orphan_cluster]++;
}
orphan_cluster = get_fat_entry(orphan_cluster, image_buf, bpb);
orphan_size++;
}
//got to concatanate stuff
struct direntry *dirent = (struct direntry*)root_dir_addr(image_buf, bpb);
char name[5];
sprintf(name, "%d", count);
char str[1024] = "";
strcat(str, "located");
strcat(str, name);
strcat(str, ".dat\0");
char * file_name = str;
create_dirent(dirent, file_name, i, orphan_size * 512, image_buf, bpb);
printf("added %s to directory \n", str);
printf("orphan cluster chain size = %d \n", orphan_size);
}
}
printf("orphans saved: %d\n", count);
}
void traverse_root(uint8_t *image_buf, struct bpb33* bpb)
{
uint16_t cluster = 0;
struct direntry *dirent = (struct direntry*)cluster_to_addr(cluster, image_buf, bpb);
printf("The address of the first dirent is: %lu\n", dirent);
int i = 0;
for ( ; i < bpb->bpbRootDirEnts; i++)
{
uint16_t followclust = print_dirent(dirent, 0);
if (is_valid_cluster(followclust, bpb))
follow_dir(followclust, 1, image_buf, bpb);
dirent++;
}
}
void traverse_root(uint8_t *image_buf, struct bpb33* bpb)
{
uint16_t cluster = 0;
struct direntry *dirent = (struct direntry*)cluster_to_addr(cluster, image_buf, bpb);
int i = 0;
for ( ; i < bpb->bpbRootDirEnts; i++)
{
uint16_t followclust = print_dirent(dirent, 0);
if (is_valid_cluster(followclust, bpb)){
//dirent->deReferenceCount=1;
follow_dir(followclust, 1, image_buf, bpb);
}
dirent++;
}
//printf("ReferenceCount= %d\n", dirent->deReferenceCount);
}
/*
* helper function that fixes a single orphan and makes
* a DAT file associated with the cluster
*/
int foster_single_orphan(int orphan_count, uint16_t curr_cluster,
uint8_t *image_buf, struct bpb33* bpb) {
orphan_count++;
int cluster = 0;
struct direntry* dirent = (struct direntry*)
cluster_to_addr(cluster, image_buf, bpb);
char filename[13]; char str[3];
// make file name
memset(filename, '\0', 13); strcat(filename, "found");
memset(str, '\0', 3);
sprintf(str, "%d", orphan_count);
strcat(filename, str); strcat(filename, ".dat");
int clusters_size = size_of_cluster(curr_cluster, image_buf, bpb);
append_clusters(cluster);
create_dirent(dirent, filename, curr_cluster,
clusters_size, image_buf, bpb);
return orphan_count;
}
void follow_dir(uint16_t cluster, int indent,
uint8_t *image_buf, struct bpb33* bpb)
{
while (is_valid_cluster(cluster, bpb))
{
struct direntry *dirent = (struct direntry*)cluster_to_addr(cluster, image_buf, bpb);
int numDirEntries = (bpb->bpbBytesPerSec * bpb->bpbSecPerClust) / sizeof(struct direntry);
int i = 0;
for ( ; i < numDirEntries; i++)
{
uint16_t followclust = print_dirent(dirent, indent);
if (followclust)
follow_dir(followclust, indent+1, image_buf, bpb);
dirent++;
}
cluster = get_fat_entry(cluster, image_buf, bpb);
}
}
void traverse_root(char * filename, uint8_t *image_buf, struct bpb33* bpb)
{
uint16_t cluster = 0;
struct direntry *dirent = (struct direntry*)cluster_to_addr(cluster, image_buf, bpb);
int i = 0;
for ( ; i < bpb->bpbRootDirEnts; i++)
{
uint16_t followclust = print_dirent(filename,dirent, 0);
if (is_valid_cluster(followclust, bpb)) {
follow_dir(filename, followclust, 1, image_buf, bpb);
printf("Cluster is valid\n");
}
dirent++;
}
printf("finished going through stuff\n");
//
find_orphans(image_buf, bpb);
}
void check_lost_files(int usedClusters[], uint16_t cluster, uint8_t *image_buf, struct bpb33* bpb)
{
// A value of 1 means that the cluster is used somewhere.
usedClusters[cluster] = 1;
struct direntry *dirent;
int d, i;
dirent = (struct direntry*) cluster_to_addr(cluster, image_buf, bpb);
int clust_size = bpb->bpbBytesPerSec * bpb->bpbSecPerClust;
while (1) {
for (d = 0; d < clust_size; d += sizeof(struct direntry)) {
char name[9];
char extension[4];
uint32_t size;
uint16_t file_cluster;
name[8] = ' ';
extension[3] = ' ';
memcpy(name, &(dirent->deName[0]), 8);
memcpy(extension, dirent->deExtension, 3);
if (name[0] == SLOT_EMPTY)
return;
/* skip over deleted entries */
if (((uint8_t)name[0]) == SLOT_DELETED)
continue;
/* names are space padded - remove the spaces */
for (i = 8; i > 0; i--) {
if (name[i] == ' ')
name[i] = '\0';
else
break;
}
/* remove the spaces from extensions */
for (i = 3; i > 0; i--) {
if (extension[i] == ' ')
extension[i] = '\0';
else
break;
}
/* don't print "." or ".." directories */
if (strcmp(name, ".") == 0) {
dirent++;
continue;
}
if (strcmp(name, "..") == 0) {
dirent++;
continue;
}
if ((dirent->deAttributes & ATTR_VOLUME) != 0) {
} else if ((dirent->deAttributes & ATTR_DIRECTORY) != 0) {
file_cluster = getushort(dirent->deStartCluster);
check_lost_files(usedClusters, file_cluster, image_buf, bpb);
} else {
/* We have a file. We should follow the file and remove all the used clusters from our collection! */
size = getulong(dirent->deFileSize);
uint16_t file_cluster_begin = getushort(dirent->deStartCluster);
//uint16_t cluster, uint32_t bytes_remaining, uint8_t *image_buf, struct bpb33* bpb
mark_file_clusters_used(usedClusters, file_cluster_begin, size, image_buf, bpb);
}
dirent++;
}
/* We've reached the end of the cluster for this directory. Where's the next cluster? */
if (cluster == 0) {
// root dir is special
dirent++;
} else {
cluster = get_fat_entry(cluster, image_buf, bpb);
dirent = (struct direntry*) cluster_to_addr(cluster, image_buf, bpb);
}
}
}
int main(int argc, char** argv)
{
uint8_t *image_buf;
int fd;
struct bpb33* bpb;
if (argc != 2) {
usage();
}
image_buf = mmap_file(argv[1], &fd);
bpb = check_bootsector(image_buf);
int total_clusters = bpb->bpbSectors / bpb->bpbSecPerClust;
int clust_size = bpb->bpbSecPerClust * bpb->bpbBytesPerSec;
int used_clusters[total_clusters];
check_lost_files(used_clusters, 0, image_buf, bpb);
int i;
int shownPrefix = 0;
for (i = 2; i < total_clusters; i++) {
if (used_clusters[i] == 0 && get_fat_entry(i, image_buf, bpb) != CLUST_FREE) {
if (!shownPrefix) {
printf("Unreferenced:");
shownPrefix = 1;
}
printf(" %i", i);
}
if (i == total_clusters - 1 && shownPrefix) {
printf("\n");
}
}
int foundCount = 1;
shownPrefix = 0;
for (i = 2; i < total_clusters; i++) {
if (used_clusters[i] == 0 && get_fat_entry(i, image_buf, bpb) != CLUST_FREE) {
if (!shownPrefix) {
printf("Lost File: ");
}
uint16_t size = get_file_length(i, image_buf, bpb);
printf("%i %i\n", i, size);
struct direntry *dirent = (struct direntry*) cluster_to_addr(0, image_buf, bpb);
uint32_t size_bytes = size * clust_size;
const char base[] = "found";
const char extension[] = ".dat";
char filename [13];
sprintf(filename, "%s%i%s", base, foundCount++, extension);
create_dirent(dirent, filename, i, size_bytes, image_buf, bpb);
check_lost_files(used_clusters, 0, image_buf, bpb);
}
if (i == total_clusters - 1 && shownPrefix) {
printf("\n");
}
}
check_file_length(0, image_buf, bpb);
close(fd);
exit(0);
}
void check_file_length(uint16_t cluster, uint8_t *image_buf, struct bpb33* bpb)
{
struct direntry *dirent;
int d, i;
dirent = (struct direntry*) cluster_to_addr(cluster, image_buf, bpb);
int clust_size = bpb->bpbBytesPerSec * bpb->bpbSecPerClust;
while (1) {
for (d = 0; d < clust_size; d += sizeof(struct direntry)) {
char name[9];
char extension[4];
uint32_t size;
uint16_t file_cluster;
name[8] = ' ';
extension[3] = ' ';
memcpy(name, &(dirent->deName[0]), 8);
memcpy(extension, dirent->deExtension, 3);
if (name[0] == SLOT_EMPTY)
return;
/* skip over deleted entries */
if (((uint8_t)name[0]) == SLOT_DELETED)
continue;
/* names are space padded - remove the spaces */
for (i = 8; i > 0; i--) {
if (name[i] == ' ')
name[i] = '\0';
else
break;
}
/* remove the spaces from extensions */
for (i = 3; i > 0; i--) {
if (extension[i] == ' ')
extension[i] = '\0';
else
break;
}
/* don't print "." or ".." directories */
if (strcmp(name, ".") == 0) {
dirent++;
continue;
}
if (strcmp(name, "..") == 0) {
dirent++;
continue;
}
if ((dirent->deAttributes & ATTR_VOLUME) != 0) {
continue;
} else if ((dirent->deAttributes & ATTR_DIRECTORY) != 0) {
file_cluster = getushort(dirent->deStartCluster);
check_file_length(file_cluster, image_buf, bpb);
} else {
size = getulong(dirent->deFileSize);
file_cluster = getushort(dirent->deStartCluster);
uint16_t fat_size_clusters = get_file_length(file_cluster, image_buf, bpb);
uint32_t size_clusters = (size + (clust_size - 1)) / clust_size;
uint32_t fat_size = fat_size_clusters * clust_size;
if (size_clusters != fat_size_clusters) {
printf("%s.%s %u %u\n", name, extension, size, fat_size);
uint16_t begin_cluster = file_cluster + size_clusters - 1;
uint16_t end_cluster = file_cluster + fat_size_clusters;
free_clusters(begin_cluster, end_cluster, image_buf, bpb);
}
}
dirent++;
}
/* We've reached the end of the cluster for this directory. Where's the next cluster? */
if (cluster == 0) {
// root dir is special
dirent++;
} else {
cluster = get_fat_entry(cluster, image_buf, bpb);
dirent = (struct direntry*) cluster_to_addr(cluster, image_buf, bpb);
}
}
}
