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simulatedFileSystem.c
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simulatedFileSystem.c
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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <stdbool.h>
/* command action
* ------- ------
* root initialize root directory
* print print current working directory and all descendants
* chdir change current working directory (.. refers to parent directory)
* mkdir sub-directory create
* rmdir delete
* mvdir rename
* mkfil file create
* rmfil delete
* mvfil rename
* szfil resize
* exit quit the program
*/
int debug = 1; // extra output; 1 = on, 0 = off
int do_root (char *name, char *size);
int do_print(char *name, char *size);
int do_chdir(char *name, char *size);
int do_mkdir(char *name, char *size);
int do_rmdir(char *name, char *size);
int do_mvdir(char *name, char *size);
int do_mkfil(char *name, char *size);
int do_rmfil(char *name, char *size);
int do_mvfil(char *name, char *size);
int do_szfil(char *name, char *size);
int do_exit (char *name, char *size);
/*
returns 0 (success) or -1 (failure)
*/
struct action {
char *cmd; // pointer to string
int (*action)(char *name, char *size); // pointer to function
} table[] = {
{ "root" , do_root },
{ "print", do_print },
{ "chdir", do_chdir },
{ "mkdir", do_mkdir },
{ "rmdir", do_rmdir },
{ "mvdir", do_mvdir },
{ "mkfil", do_mkfil },
{ "rmfil", do_rmfil },
{ "mvfil", do_mvfil },
{ "szfil", do_szfil },
{ "exit" , do_exit },
{ NULL, NULL } // end mark, do not remove ,gives wierd errors! :(
};
/*--------------------------------------------------------------------------------*/
void printing(char *name);
void print_descriptor ( );
void parse(char *buf, int *argc, char *argv[]);
int allocate_block (char *name, bool directory ) ;
void unallocate_block ( int offset );
int find_block ( char* name, bool directory );
int add_descriptor ( char * name );
int edit_descriptor ( int free_index, bool free, int name_index, char * name );
int edit_descriptor_name (int index, char* new_name);
int add_directory( char * name );
int remove_directory( char * name );
int rename_directory( char *name, char *new_name );
int edit_directory ( char * name, char*subitem_name, char *new_name, bool name_change, bool directory );
int add_file( char * name, int size );
int edit_file ( char * name, int size, char *new_name );
int remove_file (char* name);
int edit_directory_subitem (char* name, char* sub_name, char* new_sub_name);
void print_directory ( char *name);
char * get_directory_name ( char*name );
char * get_directory_top_level ( char*name);
char * get_directory_subitem ( char*name, int subitem_index, char * subitem );
int get_directory_subitem_count ( char*name);
char * get_file_name ( char*name );
char * get_file_top_level ( char*name);
int get_file_size( char*name);
void print_file ( char *name);
/************************** Defining Constants for fs *******************/
#define LINESIZE 128
#define DISK_PARTITION 4000000
#define BLOCK_SIZE 5000
#define BLOCKS 4000000/5000
#define MAX_STRING_LENGTH 20
#define MAX_FILE_DATA_BLOCKS (BLOCK_SIZE-64*59) //Hard-coded as of now
#define MAX_SUBDIRECTORIES (BLOCK_SIZE - 136)/MAX_STRING_LENGTH
typedef struct {
char directory[MAX_STRING_LENGTH];
int directory_index;
char parent[MAX_STRING_LENGTH];
int parent_index;
} working_directory;
typedef struct dir_type {
char name[MAX_STRING_LENGTH]; //Name of file or dir
char top_level[MAX_STRING_LENGTH]; //Name of directory one level up(immediate parent)
char (*subitem)[MAX_STRING_LENGTH];
bool subitem_type[MAX_SUBDIRECTORIES]; //true if directory, false if file
int subitem_count;
struct dir_type *next;
} dir_type;
typedef struct file_type {
char name[MAX_STRING_LENGTH]; //Name of file or dir
char top_level[MAX_STRING_LENGTH]; //Name of directory one level up
int data_block_index[MAX_FILE_DATA_BLOCKS];
int data_block_count;
int size;
struct file_type *next;
} file_type;
typedef struct {
bool free[BLOCKS];
bool directory[BLOCKS];
char (*name)[MAX_STRING_LENGTH];
} descriptor_block;
char *disk;
working_directory current;
bool disk_allocated = false; // makes sure that do_root is first thing being called and only called once
/*--------------------------------------------------------------------------------*/
int main(int argc, char *argv[])
{
(void)argc;
(void)*argv;
char in[LINESIZE];
char *cmd, *fnm, *fsz;
char dummy[] = "";
//printf("sizeof file_type = %d\nsizeof dir_type = %d\nsize of descriptor_block = %d\nMAX_FILE_SIZE %d\n", sizeof(file_type), sizeof(dir_type), sizeof(descriptor_block), MAX_FILE_DATA_BLOCKS );
printf("Welcome to your file system\n");
int n;
char *a[LINESIZE];
while (fgets(in, LINESIZE, stdin) != NULL)
{
// commands are all of form "cmd filename filesize\n" with whitespace as a delimiter
// parse input
parse(in, &n, a);
cmd = (n > 0) ? a[0] : dummy;
fnm = (n > 1) ? a[1] : dummy;
fsz = (n > 2) ? a[2] : dummy;
if (debug) printf(":%s:%s:%s:\n", cmd, fnm, fsz);
if (n == 0) continue; // blank line
int found = 0;
for (struct action *ptr = table; ptr->cmd != NULL; ptr++){
if (strcmp(ptr->cmd, cmd) == 0)
{
found = 1;
int ret = (ptr->action)(fnm, fsz);
//every function returns -1 on failure
if (ret == -1)
{ printf(" %s %s %s: failed\n", cmd, fnm, fsz); }
break;
}
}
if (!found) { printf("command not found: %s\n", cmd);}
}
return 0;
}
/*--------------------------------------------------------------------------------*/
void parse(char *buf, int *argc, char *argv[])
{
char *delim; // points to first space delimiter
int count = 0; // number of args
char whsp[] = " \t\n\v\f\r"; // whitespace characters
while (1) // build the argv list
{
buf += strspn(buf, whsp); // skip leading whitespace
delim = strpbrk(buf, whsp); // next whitespace char or NULL
if (delim == NULL) // end of line, input parsed
{ break; }
argv[count++] = buf;
*delim = '\0';
buf = delim + 1;
}
argv[count] = NULL;
*argc = count;
return;
}
/*--------------------------------------------------------------------------------*/
//This function initializes the disk, descriptor within the disk, as well as the root directory.
int do_root(char *name, char *size)
{
(void)*name;
(void)*size;
if ( disk_allocated == true )
return 0;
//Initialize disk
disk = (char*)malloc ( DISK_PARTITION );
if ( debug ) printf("\t[%s] Allocating [%d] Bytes of memory to the disk\n", __func__, DISK_PARTITION );
//Add descriptor and root directory to disk
add_descriptor("descriptor");
if ( debug ) printf("\t[%s] Creating Descriptor Block\n", __func__ );
add_directory("root");
if ( debug ) printf("\t[%s] Creating Root Directory\n", __func__ );
//Set up the working_directory structure
strcpy(current.directory, "root");
current.directory_index = 3;
strcpy(current.parent, "" );
current.parent_index = -1;
if ( debug ) printf("\t[%s] Set Current Directory to [%s], with Parent Directory [%s]\n", __func__, "root", "" );
if ( debug ) printf("\t[%s] Disk Successfully Allocated\n", __func__ );
disk_allocated = true;
return 0;
}
/*--------------------------------------------------------------------------------*/
int do_print(char *name, char *size)
{
(void)*name;
(void)*size;
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
//Start with the root directory, which is directory type (true)
printing("root");
if (debug) if ( debug ) printf("\n\t[%s] Finished printing\n", __func__);
return 0;
}
/*--------------------------------------------------------------------------------*/
int do_chdir(char *name, char *size)
{
(void)*size;
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
//Case if ".." is the argument to "chdir"
if ( strcmp(name, ".." ) == 0 ) {
//If we are in root directory then we can't go back
if ( strcmp(current.directory, "root") == 0 )
return 0;
//Adjust the working_directory struct
strcpy ( current.directory, current.parent );
strcpy (current.parent, get_directory_top_level( current.parent) );
if ( debug ) printf ("\t[%s] Current Directory is now [%s], Parent Directory is [%s]\n", __func__, current.directory, current.parent);
return 0;
}
else
{
char tmp[20];
//Check to make sure it is a subdirectory that is to be changed
//If name is not in the current directory then returns -1, else return 0
if ( (strcmp(get_directory_subitem(current.directory, -1, name), "-1") == 0) && strcmp( current.parent, name ) != 0 ) {
if ( debug ) printf( "\t\t\t[%s] Cannot Change to Directory [%s]\n", __func__, name );
if (!debug ) printf( "%s: %s: No such file or directory\n", "chdir", name );
return 0;
}
strcpy( tmp, get_directory_name(name));
if ( strcmp(tmp, "") == 0 )
return 0;
if ( strcmp( tmp, name ) == 0 ) {
//Adjust the working_directory struct
strcpy ( current.directory, tmp);
strcpy(current.parent, get_directory_top_level(name) );
if ( debug ) printf ("\t[%s] Current Directory is now [%s], Parent Directory is [%s]\n", __func__, current.directory, current.parent);
return 1;
}
return -1;
}
return 0;
}
/*--------------------------------------------------------------------------------*/
int do_mkdir(char *name, char *size)
{
(void)*size;
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
//If it returns 0, there is a subitem with that name already
if ( get_directory_subitem(current.directory, -1, name) == 0 ) {
if ( debug ) printf( "\t\t\t[%s] Cannot Make Directory [%s]\n", __func__, name );
if (!debug ) printf( "%s: cannot create directory '%s': Folder exists\n", "mkdir", name );
return 0;
}
//Call add directory
if ( debug ) printf("\t[%s] Creating Directory: [%s]\n", __func__, name );
if ( add_directory( name ) != 0 ) {
if (!debug ) printf("%s: missing operand\n", "mkdir");
return 0;
}
//Edit the current directory to add our new directory to the current directory's "subdirectory" member.
//NULL ==> for just editing the subdirectory
edit_directory( current.directory, name, NULL, false, true );
if ( debug ) printf("\t[%s] Updating Parents Subitem content\n", __func__ );
if ( debug ) printf("\t[%s] Directory Created Successfully\n", __func__ );
if( debug ) print_directory(name);
return 0;
}
/*--------------------------------------------------------------------------------*/
int do_rmdir(char *name, char *size)
{
(void)*size;
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
if ( strcmp(name,"") == 0 ) {
if ( debug ) printf("\t[%s] Invalid Command\n", __func__ );
if (!debug ) printf("%s: missing operand\n", "rmdir");
return 0;
}
if( (strcmp(name, ".") == 0) || (strcmp(name, "..") == 0) ) {
if ( debug ) printf("\t[%s] Invalid command [%s] Will not remove directory\n", __func__, name);
if (!debug ) printf( "%s: %s: No such file or directory\n", "rmdir", name );
return 0;
}
//Check to make sure it is a subdirectory that is to be changed
//If name is not in the current directory then returns -1, else return 0
if ( strcmp(get_directory_subitem(current.directory, -1, name), "-1") == 0 ) {
if ( debug ) printf( "\t[%s] Cannot Remove Directory [%s]\n", __func__, name );
if (!debug ) printf( "%s: %s: No such file or directory\n", "rmdir", name );
return 0;
}
//Remove directory from the parent's subitems.
dir_type *folder = malloc ( BLOCK_SIZE );
int block_index = find_block(name, true);
memcpy( folder, disk + block_index*BLOCK_SIZE, BLOCK_SIZE );
dir_type *top_folder = malloc ( BLOCK_SIZE );
//The top_level is created based off the folder
int top_block_index = find_block(folder->top_level, true);
memcpy( disk + block_index*BLOCK_SIZE, folder, BLOCK_SIZE );
memcpy( top_folder, disk + top_block_index*BLOCK_SIZE, BLOCK_SIZE );
char subitem_name[MAX_STRING_LENGTH]; // holds the current subitem in the parent directory array
const int subcnt = top_folder->subitem_count; // no. of subitems
int j;
int k=0;
//iterate through the subitem count
for(j = 0; j<subcnt; j++) {
strcpy(subitem_name, top_folder->subitem[j]);
if (strcmp(subitem_name, name) != 0)
{
strcpy(top_folder->subitem[k],subitem_name);
//printf("------ Subitem [%s] copied ------\n", subitem_name);
k++;
}
}
//Remove the directory subitem from the parent
strcpy(top_folder->subitem[k], "");
top_folder->subitem_count--;
memcpy( disk + top_block_index*BLOCK_SIZE, top_folder, BLOCK_SIZE );
free(top_folder);
//Remove the directory with its contents
if ( debug ) printf("\t[%s] Removing Directory: [%s]\n", __func__, name );
if( remove_directory( name ) == -1 ) {
return 0;
}
if (debug) printf("\t[%s] Directory Removed Successfully\n", __func__);
return 0;
}
/*--------------------------------------------------------------------------------*/
int do_mvdir(char *name, char *size) //"size" is actually the new name
{
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
//Rename the directory
if ( debug ) printf("\t[%s] Renaming Directory: [%s]\n", __func__, name );
//if the directory "name" is not found, return -1
if( edit_directory( name, "", size, true, true ) == -1 ) {
if (!debug ) printf( "%s: cannot rename file or directory '%s'\n", "mvdir", name );
return 0;
}
//else the directory is renamed
if (debug) printf( "\t[%s] Directory Renamed Successfully: [%s]\n", __func__, size );
if (debug) print_directory(size);
return 0;
}
/*--------------------------------------------------------------------------------*/
int do_mkfil(char *name, char *size)
{
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
if ( debug ) printf("\t[%s] Creating File: [%s], with Size: [%s]\n", __func__, name, size );
//If it returns 0, there is a subitem with that name already
if ( get_directory_subitem(current.directory, -1, name) == 0 ) {
if ( debug ) printf( "\t\t\t[%s] Cannot make file [%s], a file or directory [%s] already exists\n", __func__, name, name );
if (!debug ) printf( "%s: cannot create file '%s': File exists\n", "mkfil", name );
return 0;
}
if ( add_file ( name, atoi(size)) != 0 )
return 0;
//Edit the current directory to add our new file to the current directory's "subdirectory" member.
edit_directory( current.directory, name, NULL, false, false);
if ( debug ) printf("\t[%s] Updating Parents Subitem content\n", __func__ );
if ( debug ) print_file(name);
return 0;
}
/*--------------------------------------------------------------------------------*/
// Remove a file
int do_rmfil(char *name, char *size)
{
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
(void)*size;
if ( debug ) printf("\t[%s] Removing File: [%s]\n", __func__, name);
//If the file to be removed actually exists in current directory, remove it
if ( get_directory_subitem(current.directory, -1, name) == 0 ) {
remove_file(name);
return 0;
}
else{ // If it doesn't exist, print error and return 0
if ( debug ) printf( "\t\t\t[%s] Cannot remove file [%s], it does not exist in this directory\n", __func__, name );
if (!debug ) printf( "%s: %s: No such file or directory\n", "rmfil", name );
return 0;
}
}
/*--------------------------------------------------------------------------------*/
// Rename a file
int do_mvfil(char *name, char *size)
{
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
if ( debug ) printf("\t[%s] Renaming File: [%s], to: [%s]\n", __func__, name, size );
//If it returns 0, there is a subitem with that name already
if ( get_directory_subitem(current.directory, -1, size) == 0 ) {
if ( debug ) printf( "\t\t\t[%s] Cannot rename file [%s], a file or directory [%s] already exists\n", __func__, name, size );
if (!debug ) printf( "%s: cannot rename file or directory '%s'\n", "mvfil", name );
return 0;
}
int er = edit_file( name, 0, size);
if (er == -1) return -1;
if (debug) print_file(size);
return 0;
}
/*--------------------------------------------------------------------------------*/
// Resize a file -- addon to be implemented
int do_szfil(char *name, char *size)
{
if ( disk_allocated == false ) {
printf("Error: Disk not allocated\n");
return 0;
}
if ( debug ) printf("\t[%s] Resizing File: [%s], to: [%s]\n", __func__, name, size );
//remove file; make new file with updated size
if (remove_file(name) != -1) do_mkfil(name, size);
else {
if ( debug ) printf("\t[%s] File: [%s] does not exist. Cannot resize.\n", __func__, name);
if (!debug ) printf( "%s: cannot resize '%s': No such file or directory\n", "szfil", name );
}
return 0;
}
/*--------------------------------------------------------------------------------*/
int do_exit(char *name, char *size)
{
(void)*name;
(void)*size;
if (debug) printf("\t[%s] Exiting\n", __func__);
exit(0);
return 0;
}
/*--------------------------------------------------------------------------------*/
/******************************* Helper Functions Start *****************************/
//Prints the information of directories and files starting at the root
void printing(char *name) {
//Allocate memory to a dir_type so that we can copy the folder from memory into this variable.
dir_type *folder = malloc (BLOCK_SIZE);
int block_index = find_block(name, true);
memcpy( folder, disk + block_index*BLOCK_SIZE, BLOCK_SIZE);
printf("%s:\n", folder->name);
for( int i = 0; i < folder->subitem_count; i++ ) {
printf("\t%s\n", folder->subitem[i]);
}
//Go through again if there is a subdirectory
for( int i = 0; i < folder->subitem_count; i++ ) {
if( folder->subitem_type[i] == true ) {
//Recursively call the function! can be improved further ;)
printing(folder->subitem[i]);
}
}
}
/*--------------------------------------------------------------------------------*/
//Displays the content of the descriptor block and free block table.
void print_descriptor ( ) {
descriptor_block *descriptor = malloc( BLOCK_SIZE*2 );
memcpy ( descriptor, disk, BLOCK_SIZE*2 );
printf("Disk Descriptor Free Table:\n");
for ( int i = 0; i < BLOCKS ; i++ ) {
printf("\tIndex %d : %d\n", i, descriptor->free[i]);
}
free(descriptor);
}
/*--------------------------------------------------------------------------------*/
//finds the first free block on the disk; the free block index is returned
int allocate_block ( char *name, bool directory ) {
descriptor_block *descriptor = malloc( BLOCK_SIZE*2);
memcpy ( descriptor, disk, BLOCK_SIZE*2 );
//Goes through every block until free one is found
if ( debug ) printf("\t\t\t[%s] Finding Free Memory Block in the Descriptor\n", __func__ );
for ( int i = 0; i < BLOCKS; i++ ) {
if ( descriptor->free[i] ) {
//Once free block is found, update descriptor information
descriptor->free[i] = false;
descriptor->directory[i] = directory;
strcpy(descriptor->name[i], name);
//update descriptor back to the beginning of the disk
memcpy(disk, descriptor, BLOCK_SIZE*2);
if ( debug ) printf("\t\t\t[%s] Allocated [%s] at Memory Block [%d]\n", __func__, name, i );
free(descriptor);
return i;
}
}
free(descriptor);
if ( debug ) printf("\t\t\t[%s] No Free Space Found: Returning -1\n", __func__);
return -1;
}
/*--------------------------------------------------------------------------------*/
//updates the descriptor block on disk to reflect that the block is no longer in use.
void unallocate_block ( int offset ) {
descriptor_block *descriptor = malloc( BLOCK_SIZE*2 );
memcpy ( descriptor, disk, BLOCK_SIZE*2 );
//TODO: check if the block holds a file, and then unallocate all its sub-block
if ( debug ) printf("\t\t\t[%s] Unallocating Memory Block [%d]\n", __func__, offset );
descriptor->free[offset] = true;
strcpy( descriptor->name[offset], "" );
memcpy ( disk, descriptor, BLOCK_SIZE*2 );
free(descriptor);
}
/*--------------------------------------------------------------------------------*/
//Takes in a name, and searches through descriptor block to find the block that contains the item
int find_block ( char *name, bool directory ) {
descriptor_block *descriptor = malloc( BLOCK_SIZE*2 );
memcpy ( descriptor, disk, BLOCK_SIZE*2 );
if ( debug ) printf("\t\t\t[%s] Searching Descriptor for [%s], which is a [%s]\n", __func__, name, directory == true ? "Folder": "File" );
for ( int i = 0; i < BLOCKS; i++ ) {
if ( strcmp(descriptor->name[i], name) ==0 ){
//Make sure it is of the type that we are searching for
if ( descriptor->directory[i] == directory ) {
if ( debug ) printf("\t\t\t[%s] Found [%s] at Memory Block [%d]\n", __func__, name, i );
free(descriptor);
//Return the block index where the item resides in memory
return i;
}
}
}
free(descriptor);
if ( debug ) printf("\t\t\t[%s] Block Not Found: Returning -1\n", __func__);
return -1;
}
/*--------------------------------------------------------------------------------*/
int add_descriptor ( char * name ) {
//Allocate memory to a descriptor_block type so that we start assigning values to its members.
descriptor_block *descriptor = malloc( BLOCK_SIZE*2);
if ( debug ) printf("\t\t[%s] Allocating Space for Descriptor Block\n", __func__);
//Allocate memory to the array of strings within the descriptor block, which holds the name of each block
descriptor->name = malloc ( sizeof*name*BLOCKS );
if ( debug ) printf("\t\t[%s] Allocating Space for Descriptor's Name Member\n", __func__);
//initialize each block ==> that it is free
if ( debug ) printf("\t\t[%s] Initializing Descriptor to Have All of Memory Available\n", __func__);
for (int i = 0; i < BLOCKS; i++ ) {
descriptor->free[i] = true;
descriptor->directory[i] = false;
}
//descriptor occupied space on the disk
int limit = (int)(sizeof(descriptor_block)/BLOCK_SIZE) + 1;
if ( debug ) printf("\t\t[%s] Updating Descriptor to Show that first [%d] Memory Blocks Are Taken\n", __func__, limit+1);
for ( int i = 0; i < limit; i ++ ) {
descriptor->free[i]= false; //marking space occupied by descriptor as used
}
strcpy(descriptor->name[0], "descriptor");
//writing new updated descriptor to the beginning of the disk
//may encounter error here, to be fixed
memcpy ( disk, descriptor, (BLOCK_SIZE*(limit+1)));
return 0;
}
/*--------------------------------------------------------------------------------*/
//Allows us to directly update values in the descriptor block.
int edit_descriptor ( int free_index, bool free, int name_index, char * name ) {
descriptor_block *descriptor = malloc( BLOCK_SIZE*2 );
//Copy descriptor on disk to our descriptor_block type,
memcpy ( descriptor, disk, BLOCK_SIZE*2 );
//Each array in the descriptor block will be updated
if ( free_index > 0 ) {
descriptor->free[free_index] = free;
if ( debug ) printf("\t\t[%s] Descriptor Free Member now shows Memory Block [%d] is [%s]\n", __func__, free_index, free == true ? "Free": "Used");
}
if ( name_index > 0 ) {
strcpy(descriptor->name[name_index], name );
if ( debug ) printf("\t\t[%s] Descriptor Name Member now shows Memory Block [%d] has Name [%s]\n", __func__, name_index, name);
}
// write the new updated descriptor back to the beginning of the disk
memcpy(disk, descriptor, BLOCK_SIZE*2);
return 0;
}
/*--------------------------------------------------------------------------------*/
// This changes the name of a file in the descriptor; used for moving files;
int edit_descriptor_name (int index, char* new_name)
{
descriptor_block *descriptor = malloc( BLOCK_SIZE*2 );
memcpy ( descriptor, disk, BLOCK_SIZE*2 );
// Change the name of the file at index to the new_name
strcpy(descriptor->name[index], new_name);
memcpy(disk, descriptor, BLOCK_SIZE*2);
free(descriptor);
return 0;
}
/*--------------------------------------------------------------------------------*/
//Allows us to add a folder to the disk.
int add_directory( char * name ) {
if ( strcmp(name,"") == 0 ) {
if ( debug ) printf("\t\t[%s] Invalid Command\n", __func__ );
return -1;
}
//Allocating memory for new folder
dir_type *folder = malloc ( BLOCK_SIZE);
if ( debug ) printf("\t\t[%s] Allocating Space for New Folder\n", __func__);
//Initialize our new folder
strcpy(folder->name, name);
strcpy(folder->top_level, current.directory);
folder->subitem = malloc ( sizeof*(folder->subitem)*MAX_SUBDIRECTORIES);
folder->subitem_count = 0; // Imp : Initialize subitem array to have 0 elements
//Find free block in disk to store our folder; true => mark the block as directory
int index = allocate_block(name, true);
if ( debug ) printf("\t\t[%s] Assigning New Folder to Memory Block [%d]\n", __func__, index);
//Copy our folder to the disk
memcpy( disk + index*BLOCK_SIZE, folder, BLOCK_SIZE);
if ( debug ) printf("\t\t[%s] Folder [%s] Successfully Added\n", __func__, name);
free(folder);
return 0;
}
/*--------------------------------------------------------------------------------*/
//Allows to remove a directory folder from the disk.
int remove_directory( char * name ) {
dir_type *folder = malloc (BLOCK_SIZE);
int block_index = find_block(name, true);
//If there was no subdirectory found, then return -1
if( block_index == -1 ) {
if ( debug ) printf("\t\t[%s] Directory [%s] does not exist in the current folder [%s]\n", __func__, name, current.directory);
return -1;
}
memcpy( folder, disk + block_index*BLOCK_SIZE, BLOCK_SIZE );
//Go through again if there is a subdirectory ==> as implemented in Unix
for( int i = 0; i < folder->subitem_count; i++ ) {
if( folder->subitem_type[i] == true ) {
//Recursively call the function to remove the subitem
remove_directory(folder->subitem[i]);
}
else {
//Remove the subitem that is a file
remove_file(folder->subitem[i]);
}
}
unallocate_block(block_index);
free(folder);
return 0;
}
/*--------------------------------------------------------------------------------*/
//Allows you to directly add items to a folders subitem array, or change the folder's name
int edit_directory (char * name, char*subitem_name, char *new_name, bool name_change, bool directory ) {
if( strcmp(name,"") == 0 ) {
if( debug ) printf("\t\t[%s] Invalid Command\n", __func__ );
return -1;
}
dir_type *folder = malloc ( BLOCK_SIZE);
//Find where the folder is on disk
int block_index = find_block(name, true);
//If the directory is not found, should return
if( block_index == -1 ) {
if ( debug ) printf("\t\t[%s] Directory [%s] does not exist\n", __func__, name);
return -1;
}
if ( debug ) printf("\t\t[%s] Folder [%s] Found At Memory Block [%d]\n", __func__, name, block_index);
memcpy( folder, disk + block_index*BLOCK_SIZE, BLOCK_SIZE);
if ( strcmp(subitem_name, "") != 0 ) { //Case that we are adding subitem to the descriptor block
if ( !name_change ) { //Case adding subitem
if ( debug ) printf("\t\t[%s] Added Subitem [%s] at Subitem index [%d] to directory [%s]\n", __func__, subitem_name, folder->subitem_count, folder->name );
strcpy (folder->subitem[folder->subitem_count], subitem_name );
folder->subitem_type[folder->subitem_count] = directory;
folder->subitem_count++;
if ( debug ) printf("\t\t[%s] Folder [%s] Now Has [%d] Subitems\n", __func__, name, folder->subitem_count);
//update the disk too!
memcpy( disk + block_index*BLOCK_SIZE, folder, BLOCK_SIZE);
free(folder);
return 0;
}
else { //Case editing a subitem's name
for ( int i =0; i < folder->subitem_count; i++ ) {
if ( strcmp(folder->subitem[i], subitem_name) == 0 ) {
strcpy( folder->subitem[i], new_name);
if ( debug ) printf("\t\t[%s] Edited Subitem [%s] to [%s] at Subitem index [%d] for directory [%s]\n", __func__, subitem_name, new_name, i, folder->name );
memcpy( disk + block_index*BLOCK_SIZE, folder, BLOCK_SIZE);
free(folder);
return 0;
}
}
if ( debug ) printf("\t\t[%s] Subitem Does Not Exist in Directory [%s]\n", __func__, folder->name );
free(folder);
return -1;
}
}
else { //Case we are changing the folders name
//if directory with given name already exists, don't allow
int block_index2 = find_block(new_name, true);
//If the directory for the new name already exists, should return -1
if( block_index2 != -1 ) {
if ( debug ) printf("\t\t[%s] Directory [%s] already exists. Choose a different name\n", __func__, new_name);
return -1;
}
strcpy(folder->name, new_name );
if ( debug ) printf("\t\t[%s] Folder [%s] Now Has Name [%s]\n", __func__, name, folder->name);
memcpy( disk + block_index*BLOCK_SIZE, folder, BLOCK_SIZE);
//edit descriptors
edit_descriptor(-1, false, block_index, new_name );
if ( debug ) printf("\t\t[%s] Updated Descriptor's Name Member\n", __func__);
if ( debug ) print_directory(folder->name);
//changing parents name
edit_directory(folder->top_level, name, new_name, true, true );
if ( debug ) printf("\t\t[%s] Updated Parents Subitem Name\n", __func__);
int child_index;
//Iterates through to change the subitems' top_level name
for ( int i = 0; i < folder->subitem_count; i++) {
file_type *child_file = malloc ( BLOCK_SIZE);
dir_type *child_folder = malloc ( BLOCK_SIZE);
child_index = find_block ( folder->subitem[i], folder->subitem_type);
if ( folder->subitem_type[i] ) {
//if type == folder
memcpy( child_folder, disk + child_index*BLOCK_SIZE, BLOCK_SIZE);
strcpy( child_folder->top_level, new_name );
memcpy( disk + child_index*BLOCK_SIZE, child_folder, BLOCK_SIZE);
free ( child_folder );
free ( child_file );
}
else {
//if type == file
memcpy( child_file, disk + child_index*BLOCK_SIZE, BLOCK_SIZE);
strcpy( child_file->top_level, new_name );
memcpy( disk + child_index*BLOCK_SIZE, child_file, BLOCK_SIZE);
free ( child_folder );
free ( child_file );
}
}
free(folder);
return 0;
}
free ( folder );
}
/*--------------------------------------------------------------------------------*/
//Allows us to add a file to our disk; This function will allocate this file descriptor block (holds file info), as well as data blocks
int add_file( char * name, int size ) {
char subname[20];
if ( size < 0 || strcmp(name,"") == 0 ) {
if ( debug ) printf("\t\t[%s] Invalid command\n", __func__);
if (!debug ) printf("%s: missing operand\n", "mkfil");
return 1;
}
//Allocate memory to a file_type
file_type *file = malloc ( BLOCK_SIZE );
if ( debug ) printf("\t\t[%s] Allocating Space for New File\n", __func__);
//Initialize all the members of our new file
strcpy( file->name, name);
strcpy ( file->top_level, current.directory );
file->size = size;
file->data_block_count = 0;
if ( debug ) printf("\t\t[%s] Initializing File Members\n", __func__);
//Find free block to put this file descriptor block in memory, false ==> indicates a file
int index = allocate_block(name, false);
//Find free blocks to put the file data into
if ( debug ) printf("\t\t[%s] Allocating [%d] Data Blocks in Memory for File Data\n", __func__, (int)size/BLOCK_SIZE);
for ( int i = 0; i < size/BLOCK_SIZE + 1; i++ ) {
sprintf(subname, "%s->%d", name, i);
file->data_block_index[i] = allocate_block(subname, false);
file->data_block_count++;
}
//data blocks in memory not copied to disk
memcpy( disk + index*BLOCK_SIZE, file, BLOCK_SIZE);
if ( debug ) printf("\t\t[%s] File [%s] Successfully Added\n", __func__, name);
free(file);
return 0;
}
/*--------------------------------------------------------------------------------*/
int remove_file (char* name)
{
if (strcmp(name,"") == 0 ) {
if ( debug ) printf("\t\t[%s] Invalid command\n", __func__);
if (!debug ) printf("%s: missing operand\n", "rmfil");
return 1;
}
file_type *file = malloc ( BLOCK_SIZE);
dir_type *folder = malloc ( BLOCK_SIZE);
int file_index = find_block(name, false);
// If the file is not found, error, return -1
if ( file_index == -1 ) {