merge and some fix

src/filesys/filehdr.rs

@@ -0,0 +1,154 @@
+use crate::simulator::disk;
+use crate::{simulator::disk::SECTOR_SIZE, utility::bitmap::BitMap};
+pub const MAX_HEADER_SECTORS: i32 = 32;
+pub const DATAS_IN_FIRST_SECTOR: i32 = (SECTOR_SIZE - 5 * 8) /8; 
+pub const DATAS_IN_SECTOR: i32 = (SECTOR_SIZE - 1 * 8) /8; 
+pub const MAX_DATA_SECTORS: i32 = ((MAX_HEADER_SECTORS-1) * DATAS_IN_SECTOR + DATAS_IN_FIRST_SECTOR);
+pub const MAX_FILE_LENGTH: i32 = ((MAX_DATA_SECTORS) * SECTOR_SIZE);
+
+use crate::DrvDisk;
+use crate::Disk;
+
+pub struct FileHdr {
+    is_dir: i32,
+    num_bytes: i32,
+    num_sectors: i32,
+    data_sectors: Vec<i32>,
+    num_header_sectors: i32,
+    header_sectors: [i32; MAX_HEADER_SECTORS as usize],
+}
+
+impl FileHdr { 
+
+    pub fn allocate(&mut self, mut free_map: BitMap, file_size: i32) -> bool {
+        self.num_bytes = file_size;
+        if file_size > MAX_FILE_LENGTH {
+            panic!("file size is too long");
+        }
+
+        self.num_sectors = (file_size + SECTOR_SIZE -1) / SECTOR_SIZE;
+        self.num_header_sectors = ((self.num_sectors - DATAS_IN_FIRST_SECTOR)+DATAS_IN_SECTOR-1) / DATAS_IN_SECTOR;
+
+        // Check if there is enough free sectors for both of them
+        if free_map.num_clear() < self.num_sectors + self.num_header_sectors {
+            return false;
+        }
+
+        for i in 0..self.num_header_sectors  {
+            self.header_sectors[i as usize]  = free_map.find();
+        }
+
+        self.data_sectors = vec![0; MAX_DATA_SECTORS as usize];
+        for i in 0..self.num_sectors  {
+            self.data_sectors[i as usize]  = free_map.find();
+        }
+
+        return true;
+    }
+
+    pub fn re_allocate(&mut self, mut free_map: BitMap, old_file_size: i32, new_file_size: i32) -> bool {
+        let mut new_num_sectors = ((new_file_size + SECTOR_SIZE -1) / SECTOR_SIZE) - self.num_sectors;
+        self.num_bytes = new_file_size;
+
+        let mut new_num_header_sectors  = (((self.num_sectors - DATAS_IN_FIRST_SECTOR)+DATAS_IN_SECTOR-1) / DATAS_IN_SECTOR) - self.num_header_sectors;
+
+        assert!(new_file_size <= MAX_FILE_LENGTH);
+
+        if free_map.num_clear() < new_num_sectors + new_num_header_sectors {
+            return false;
+        }
+        
+        for i in 0..new_num_header_sectors  {
+            self.header_sectors[(i + self.num_header_sectors)as usize]  = free_map.find();
+        }
+
+        for i in 0..new_num_sectors  {
+            self.data_sectors[(i + self.num_sectors) as usize]  = free_map.find();
+        }
+
+        return true;
+
+
+
+    }
+
+    pub fn deallocate(&mut self, mut free_map: BitMap) {
+        for i in 0..self.num_sectors {
+            assert!(free_map.test(self.data_sectors[i as usize] as usize));
+            free_map.clear(self.data_sectors[i as usize]as usize);
+        }
+
+        for i in 0..self.num_header_sectors {
+            assert!(free_map.test(self.header_sectors[i as usize] as usize));
+            free_map.clear(self.header_sectors[i as usize]as usize);
+        }
+    }
+
+    //TODO: fetchFrom WriteBack
+
+
+    pub fn byte_to_sector(&self,offset: i32) -> i32 {
+        return self.data_sectors[ (offset / SECTOR_SIZE) as usize];
+    }
+
+    pub fn file_length(&self) -> i32 {
+        return self.num_bytes;
+    }
+
+    pub fn change_file_length(&mut self, new_size: i32) {
+        self.num_bytes = new_size;
+        assert!(new_size <= MAX_FILE_LENGTH);
+
+    }
+
+    pub fn max_file_length(&self) -> i32 {
+        return self.num_sectors * SECTOR_SIZE;
+    } 
+
+    pub fn print(&self) {
+        let mut data = Vec::new();
+        println!("FileHeader contents. File size: {}. File blocks:", self.num_bytes);
+        for i in 0..self.num_sectors {
+            print!("{} ", self.data_sectors[i as usize]);
+        }
+        println!("\nFile contents:");
+        let mut k = 0;
+        for i in 0..self.num_sectors {
+            let disk = Disk::init_disk();
+            let mut drv_disk = DrvDisk::init_drv_disk(disk);
+            drv_disk.read_sector(self.data_sectors[i as usize], &mut data);
+            for j in 0..SECTOR_SIZE.min(self.num_bytes - k) {
+                let c = data[j as usize];
+                if c >= 0x20 && c <= 0x7E {
+                    print!("{}", c as char);
+                } else {
+                    print!("\\{:x}", c);
+                }
+                k += 1;
+            }
+            println!("");
+        }
+    }
+
+    pub fn is_dir(&self) -> bool{
+        return self.is_dir == 1;
+    }
+
+    pub fn set_file(&mut self) {
+        self.is_dir = 0;
+    }
+
+    pub fn set_dir(&mut self) {
+        self.is_dir = 1;
+    }
+
+}
+
+#[cfg(test)]
+mod test {
+
+    #[test]
+    fn test_allocate() {
+
+    }
+}

src/filesys/filesys.rs

@@ -1,6 +1,12 @@
-use super::directory;
+use crate::{kernel::mgerror::ErrorCode, simulator::disk, utility::bitmap::BitMap};
 
+use super::filehdr::FileHdr;
+
+pub const ERROR: i32 = -1;
+pub const FREE_MAP_SECTOR: i32 = 0;
 pub const DIRECTORY_SECTOR: i32 = 1;
+pub const NUM_DIR_ENTRIES: i32 = 10;
+pub const DIRECTORY_FILE_SIZE: i32 = 100; //std::mem::size_of<Directory>() * NUM_DIR_ENTRIES;
 
 /// decompose the name of the first directory
 /// of the path given in argument, as well as the remainder of the path.
@@ -50,7 +56,7 @@ pub fn decomp_name(origin_path: String, head: &mut String, tail: &mut String) ->
 /// - **name** is the complete name (relatively to the root directory).
 ///            its content will be modified!
 pub fn find_dir(name: &mut String) -> i32 {
-    let directory = directory::init_directory(config.num_dir_entries);
+    let directory = Directory::init_directory(config.num_dir_entries);
     directory.fetch_from(filesys::get_dir_file());
 
     let mut sector = DIRECTORY_SECTOR;
@@ -66,7 +72,7 @@ pub fn find_dir(name: &mut String) -> i32 {
             return -1; // This file/directory does not exist
         }
 
-        let file = openfile::init_open_file(sector);
+        let file = OpenFile::init_open_file(sector);
         if file.get_file_header().is_dir() {
             directory.fetch_from(&file);
         } else {
@@ -79,25 +85,403 @@ pub fn find_dir(name: &mut String) -> i32 {
 }
 
 pub struct Filesys {
-    pub free_map_file: Open_file, //Bit map of free disk blocks, represented as a file
-    pub directory_file: Open_file, //"Root" directory -- list of file names, represented as a file
+    pub free_map_file: OpenFile, //Bit map of free disk blocks, represented as a file
+    pub directory_file: OpenFile, //"Root" directory -- list of file names, represented as a file
 }
 
 impl Filesys {
-    /// Initialize the file system.
-    /// If format = true, the disk has nothing on it,
-    /// and we need to initialize the disk to contain an empty directory,
-    /// and a bitmap of free sectors (with almost but not all of the sectors marked as free).  
+    /// Initialize the file system. If format = true, the disk has
+    /// nothing on it, and we need to initialize the disk to contain
+    /// an empty directory, and a bitmap of free sectors (with almost but
+    /// not all of the sectors marked as free).  
     ///
-    ///	If format = false, we just have to open the files
-    ///	representing the bitmap and the directory.
+    /// If format = false, we just have to open the files
+    /// representing the bitmap and the directory.
+    ///
+    ///  ### parameters
+    ///
+    /// - **format** should we initialize the disk?
+    pub fn init_filesys(format: bool) -> Filesys {
+        if format {
+            let free_map = BitMap::init_bitmap(disk::NUM_SECTORS as usize);
+            let directory = Directory::init_directory(NUM_DIR_ENTRIES);
+
+            free_map.mark(FREE_MAP_SECTOR as usize);
+            free_map.mark(DIRECTORY_SECTOR as usize);
+
+            let map_header: FileHdr;
+            let dir_header: FileHdr;
+
+            map_header.allocate(free_map, FREE_MAP_SECTOR);
+            dir_header.allocate(free_map, DIRECTORY_FILE_SIZE);
+
+            dir_header.set_dir();
+
+            map_header.write_back(FREE_MAP_SECTOR);
+            dir_header.write_back(DIRECTORY_SECTOR);
+
+            let free_map_file = OpenFile::init_open_file(FREE_MAP_SECTOR);
+            let directory_file = OpenFile::init_open_file(DIRECTORY_SECTOR);
+
+            free_map.write_back(free_map_file);
+            directory.write_back(directory_file);
+
+            Filesys {
+                free_map_file,
+                directory_file,
+            }
+        } else {
+            Filesys {
+                free_map_file: OpenFile::init_open_file(FREE_MAP_SECTOR),
+                directory_file: OpenFile::init_open_file(DIRECTORY_SECTOR),
+            }
+        }
+    }
+
+    /// Create a file in the BurritOS file system (similar to UNIX create).
+    /// Since we can't increase the size of files dynamically, we have
+    /// to give Create the initial size of the file.
+    //
+    /// The steps to create a file are:
+    ///     Make sure the file doesn't already exist
+    ///     Allocate a sector for the file header
+    ///     Allocate space on disk for the data blocks for the file
+    ///     Add the name to the directory
+    ///     Store the new file header on disk
+    ///     Flush the changes to the bitmap and the directory back to disk
+    ///
+    ///	Create fails if:
+    /// 	file is already in directory
+    ///	 	no free space for file header
+    ///	 	no free entry for file in directory
+    ///	 	no free space for data blocks for the file
+    ///
+    ///	Note that this implementation assumes there is no concurrent access
+    ///	to the file system!
     ///
     /// ### parameters
     ///
-    ///	- **format** should we initialize the disk?
-    pub fn init_filesys(format: bool) -> Filesys {
-        if format {
-            let free_map = bitmap::init_bitmap();
+    ///	- **name** is the name of file to be created (NOT MODIFIED)
+    ///	- **initialSize** is the size of file to be created
+    pub fn create(self, name: String, initial_size: i32) -> Result<(), ErrorCode> {
+        lock.acquire();
+
+        let mut dir_name = name.clone();
+
+        let dir_sector = find_dir(&mut dir_name);
+        if dir_sector == ERROR {
+            lock.release();
+            return Err(ErrorCode::InexistFileError);
         }
+
+        let dir_file = OpenFile::init_open_file(dir_sector);
+        let directory = Directory::init_directory(NUM_DIR_ENTRIES);
+        directory.fetch_from(&dir_file);
+
+        if directory.find(dir_name) != ERROR {
+            lock.release();
+            return Err(ErrorCode::AlreadyInDirectory);
+        }
+
+        // Get the freemap from the disk
+        let free_map = BitMap::init_bitmap(disk::NUM_SECTORS as usize);
+        free_map.fetch_from(self.free_map_file);
+
+        // Find a sector to hold the file header
+        let sector = free_map.find();
+        if sector == ERROR {
+            lock.release();
+            return Err(ErrorCode::OutOfDisk);
+        }
+
+        // Add the file in the directory
+        let add_result = directory.add(dir_name, sector);
+        match add_result {
+            Err(e) => {
+                lock.release();
+                return Err(e);
+            }
+            _ => {}
+        }
+
+        // Indicate that this is a file, not a directory
+        let hdr = FileHdr::init_file_hdr();
+        hdr.set_file();
+
+        if !hdr.allocate(free_map, initial_size) {
+            lock.release();
+            return Err(ErrorCode::OutOfDisk);
+        }
+
+        // everthing worked, flush all changes back to disk
+        hdr.write_back(sector);
+        directory.write_back(&dir_file);
+        free_map.write_back(self.free_map_file);
+
+        lock.release();
+
+        Ok(())
+    }
+
+    /// Open a file for reading and writing.  
+    ///	To open a file:
+    ///	  Find the location of the file's header, using the directory
+    ///	  Bring the header into memory
+    ///
+    /// ### parameters
+    ///
+    ///	- **name** the text name of the file to be opened (NOT MODIFIED)
+    pub fn open(name: String) -> Option<OpenFile> {
+        let open_file: OpenFile;
+        let mut dir_name = name.clone();
+
+        // Find the directory containing the file
+        let dir_sector = find_dir(&mut dir_name);
+        if dir_sector == ERROR {
+            return None;
+        }
+
+        // Read the directory from disk
+        let dir_file = OpenFile::init_open_file(dir_sector);
+        let directory = Directory::init_directory(NUM_DIR_ENTRIES);
+        directory.fetch_from(&directory);
+
+        // Find the file in the directory
+        let sector = directory.find(dir_name);
+        if sector >= 0 {
+            open_file = OpenFile::init_open_file(sector);
+            open_file.set_name(name);
+            if open_file.is_dir() {
+                return None;
+            }
+        }
+
+        Some(open_file)
+    }
+
+    /// Delete a file from the file system.  
+    /// This requires:
+    ///	    Remove it from the directory
+    ///	    Delete the space for its header
+    ///	    Delete the space for its data blocks
+    ///	    Write changes to directory, bitmap back to disk
+    ///
+    /// ### parameters
+    ///
+    ///	- **name** the text name of the file to be removed (NOT MODIFIED)
+    pub fn remove(self, name: String) -> Result<(), ErrorCode> {
+        let mut dir_name = name.clone();
+
+        // Get the sector number of the parent directory
+        let dir_sector = find_dir(&mut dir_name);
+
+        // Check if the path is correct
+        if dir_sector == ERROR {
+            return Err(ErrorCode::InexistDirectoryError);
+        }
+
+        // Fetch the directory from the disk
+        let dir_file = OpenFile::init_open_file(dir_sector);
+        let directory = Directory::init_directory(NUM_DIR_ENTRIES);
+        directory.fetch_from(&dir_file);
+
+        // Look for the file in the directory
+        let sector = directory.find(dir_name);
+
+        // Look if we find the file in the directory
+        if sector as i32 == ERROR {
+            return Err(ErrorCode::InexistFileError);
+        }
+
+        // Fetch the file header from disk
+        let file_hdr: FileHdr;
+        file_hdr.fetch_from(self.free_map_file);
+
+        // Do nothing if it's a directory
+        if file_hdr.is_dir() {
+            return Err(ErrorCode::NotAFile);
+        }
+
+        // Get the freemap file from the disk
+        let free_map = BitMap::init_bitmap(disk::NUM_SECTORS as usize);
+        free_map.fetch_from(self.free_map_file);
+
+        // Indicate that sectors are deallocated in the freemap
+        file_hdr.deallocate(free_map);
+        free_map.clear(sector);
+
+        // Remove the file from the directory
+        directory.remove(dir_name);
+
+        // Flush everything to disk
+        free_map.write_back(self.free_map_file);
+        directory.write_back(dir_file);
+
+        Ok(())
+    }
+
+    /// List all the files in the file system directory.
+    pub fn list() {
+        //TODO
+    }
+
+    /// Print everything about the file system:
+    ///     the contents of the bitmap
+    ///	    the contents of the directory
+    ///	        for each file in the directory,
+    ///	    the contents of the file header
+    ///	    the data in the file
+    pub fn print() {
+        //TODO
+    }
+
+    /// Create a directory in the Nachos file system (similar to UNIX create).
+    ///	A directory is a file containing a table of directory entries.
+    ///
+    ///	The steps to create a dirctory are:
+    ///	    Make sure the name is valid and does not exist
+    ///     Create a file containing the directory entries  
+    ///
+    /// mkdir fails if:
+    ///     dir already exists
+    ///	 	no free space for file header
+    ///	 	no free entry for dir in directory
+    ///	 	no free space for data blocks for the file
+    ///
+    /// Note that this implementation assumes there is no concurrent access
+    ///	to the file system!
+    ///
+    /// ### parameters
+    ///
+    ///	- **name** is the name of directory to be created (NOT MODIFIED)
+    pub fn mkdir(self, name: String) -> Result<(), ErrorCode> {
+        let mut dir_name = name.clone();
+
+        // Lokk for the sector number of the parent directory
+        let parent_sector = find_dir(&mut dir_name);
+        if parent_sector < 0 {
+            return Err(ErrorCode::InexistDirectoryError);
+        }
+
+        // Fetch it from disk
+        let parent_dir_file = OpenFile::init_open_file(parent_sector);
+        let parent_dir = Directory::init_directory(NUM_DIR_ENTRIES);
+        parent_dir.fetch_from(parent_dir_file);
+
+        // Check that the directory does not exit yet
+        if parent_dir.find(dir_name) >= 0 {
+            return Err(ErrorCode::AlreadyInDirectory);
+        }
+
+        // Get the freemap
+        let free_map = BitMap::init_bitmap(disk::NUM_SECTORS as usize);
+        free_map.fetch_from(self.free_map_file);
+
+        // Get a free sector for the file header
+        let hdr_sector = free_map.find();
+        if hdr_sector < 0 {
+            return Err(ErrorCode::OutOfDisk);
+        }
+
+        // Allocate free sectors for the directory contents
+        let hdr: FileHdr;
+        if !hdr.allocate(free_map, DIRECTORY_FILE_SIZE) {
+            return Err(ErrorCode::OutOfDisk);
+        }
+
+        // Add the directory in the parent directory
+        let add_result = parent_dir.add(dir_name, hdr_sector);
+        match add_result {
+            Err(e) => {
+                return Err(e);
+            }
+            _ => {}
+        }
+
+        // File header
+        hdr.set_dir();
+        hdr.write_back(hdr_sector);
+
+        // New directory (initially empty)
+        let new_dir_file = OpenFile::init_open_file(hdr_sector as usize);
+        let new_dir = Directory::init_directory(NUM_DIR_ENTRIES);
+        new_dir.write_back(new_dir_file);
+
+        // Parent directory
+        parent_dir.write_back(parent_dir_file);
+        free_map.write_back(self.free_map_file);
+
+        Ok(())
+    }
+
+    /// Delete a directory from the file system.  
+    /// This requires:
+    ///	    check the name is valid
+    ///     check the directory  is empty   
+    ///     Remove it from its directory
+    ///	    Delete the space for its header
+    ///	    Delete the space for its data blocks
+    ///	    Write changes to directory, bitmap back to disk
+    ///
+    /// ### parameters
+    ///
+    ///	- **name** the text name of the directory to be removed (NOT MODIFIED)
+    pub fn rmdir(self, name: String) -> Result<(), ErrorCode> {
+        let mut dir_name = name.clone();
+
+        // Get the sector number of the parent directory
+        let parent_sector = find_dir(&mut dir_name);
+        if parent_sector < 0 {
+            return Err(ErrorCode::InexistDirectoryError);
+        }
+
+        // Fetch it from disk
+        let parent_dir_file = OpenFile::init_open_file(parent_sector);
+        let parent_dir = Directory::init_directory(NUM_DIR_ENTRIES);
+        parent_dir.fetch_from(parent_dir_file);
+
+        // Check that the directory to be removed exist
+        let the_dir_sector = parent_dir.find(dir_name);
+        if the_dir_sector < 0 {
+            return Err(ErrorCode::InexistDirectoryError);
+        }
+
+        // Get its header
+        let the_dir_header: FileHdr;
+        the_dir_header.fetch_from(the_dir_sector);
+
+        // Check that is is a directory
+        if !the_dir_header.is_dir() {
+            return Err(ErrorCode::NotADirectory);
+        }
+
+        // Fetch its contents from the disk
+        let the_dir_file = OpenFile::init_open_file(the_dir_sector);
+        let the_dir = Directory::init_directory(NUM_DIR_ENTRIES);
+        the_dir.fetch_from(the_dir_file);
+
+        // Check that is is empty
+        if !the_dir.empty() {
+            return Err(ErrorCode::DirectoryNotEmpty);
+        }
+
+        // Get the freemap from disk
+        let free_map = BitMap::init_bitmap(disk::NUM_SECTORS as usize);
+        free_map.fetch_from(self.free_map_file);
+
+        // Deallocate the data sectors of the directory
+        the_dir_header.deallocate(free_map);
+
+        // Deallocate the sector containing the directory header
+        free_map.clear(the_dir_sector);
+
+        // We remove the directory from its parent directory
+        parent_dir.remove(dir_name);
+
+        // Flush everything to disk
+        free_map.write_back(self.free_map_file);
+        parent_dir.write_back(parent_dir_file);
+
+        Ok(())
     }
 }

src/filesys/mod.rs

@@ -1,3 +1,6 @@
 pub mod directory;
+pub mod filehdr;
 pub mod filesys;
 pub mod fsmisc;
+pub mod oftable;
+pub mod openfile;

src/simulator/disk.rs

@@ -8,46 +8,42 @@ use std::os::unix::prelude::FileExt;
 pub const SECTORS_PER_TRACK: i32 = 32;
 pub const NUM_TRACKS: i32 = 64;
 pub const NUM_SECTORS: i32 = SECTORS_PER_TRACK * NUM_TRACKS;
-pub const SECTOR_SIZE: i32 = 4;//4 octects ?
+pub const SECTOR_SIZE: i32 = 4; //4 octects ?
 pub const DISK_PATH: &str = "disk_file";
 
-pub const MAGIC_NUMBER : u32 = 0xABBACDDC; 
+pub const MAGIC_NUMBER: u32 = 0xABBACDDC;
 //taille en octets, a confirmer
-pub const DISK_SIZE: i32 = 4 +  NUM_SECTORS*SECTOR_SIZE;//4 <=> sizeof(u32)
+pub const DISK_SIZE: i32 = 4 + NUM_SECTORS * SECTOR_SIZE; //4 <=> sizeof(u32)
 
 pub struct Disk {
-    pub last_sector: i32,//Secteur accédé lors de la précédente requête de lecture/ecriture
-    pub active: bool,//C'est notre lock -> Une seule requête de lecture/ecriture à la fois
-    pub disk_file : File //On simule le disque sur un fichier
-    //Manque une ref a une fonction type handler, fournie via constructeur dans Nachos
+    pub last_sector: i32, //Secteur accédé lors de la précédente requête de lecture/ecriture
+    pub active: bool,     //C'est notre lock -> Une seule requête de lecture/ecriture à la fois
+    pub disk_file: File,  //On simule le disque sur un fichier
+                          //Manque une ref a une fonction type handler, fournie via constructeur dans Nachos
 }
 
 impl Disk {
     pub fn init_disk() -> Disk {
-
         //see Rust File impl FileExt for File For UNIX mode
-        let mut magic_buff : [u8 ; 4] = [0u8 ; 4];
-        let mut readed_magic_number : u32;
-        let disk_file : File;
+        let mut magic_buff: [u8; 4] = [0u8; 4];
+        let mut readed_magic_number: u32;
+        let disk_file: File;
+
+        let result_open = File::options().read(true).write(true).open(DISK_PATH);
+
+        let magic_to_write: [u8; 4] = [0xAB, 0xBA, 0xCD, 0xDC];
 
-        let result_open = File::options().
-                                read(true).
-                                write(true).
-                                open(DISK_PATH);
-        
-        let magic_to_write : [u8 ; 4] = [0xAB, 0xBA, 0xCD, 0xDC];
-        
         match result_open {
-
             Err(e) => {
                 //On creer le fichier et on y écrit le magic number
                 println!("Error opening file : {}", e);
 
-                disk_file = File::options().
-                            read(true).
-                            write(true).
-                            create_new(true).
-                            open(DISK_PATH).unwrap();
+                disk_file = File::options()
+                    .read(true)
+                    .write(true)
+                    .create_new(true)
+                    .open(DISK_PATH)
+                    .unwrap();
 
                 disk_file.set_len(DISK_SIZE as u64);
                 disk_file.write_at(&magic_to_write[..], 0);
@@ -58,24 +54,27 @@ impl Disk {
                 disk_file.set_len(DISK_SIZE as u64);
                 disk_file.write_at(&magic_to_write[..], 0);
             }
-
         }
 
         match disk_file.read_at(&mut magic_buff[..], 0) {
-
             Ok(t) => {
                 println!("init_disk :: on a lu {} octets", t);
-                readed_magic_number = ((magic_buff[0] as u32) <<24)
-                                    + ((magic_buff[1] as u32) <<16)
-                                    + ((magic_buff[2] as u32) <<8)
-                                    + ((magic_buff[3] as u32) <<0);
+                readed_magic_number = ((magic_buff[0] as u32) << 24)
+                    + ((magic_buff[1] as u32) << 16)
+                    + ((magic_buff[2] as u32) << 8)
+                    + ((magic_buff[3] as u32) << 0);
 
                 if readed_magic_number != MAGIC_NUMBER {
-                    panic!("init_disk :: Did not recognize magic number at the beginning of disk_file,
-                    On a lu {:#08x}, Panic", readed_magic_number);
-                }
-                else {
-                    println!("init_disk :: on a lu le magic_number {:#08x}", readed_magic_number);
+                    panic!(
+                        "init_disk :: Did not recognize magic number at the beginning of disk_file,
+                    On a lu {:#08x}, Panic",
+                        readed_magic_number
+                    );
+                } else {
+                    println!(
+                        "init_disk :: on a lu le magic_number {:#08x}",
+                        readed_magic_number
+                    );
                 }
             }
 
@@ -83,11 +82,11 @@ impl Disk {
                 println!("init_disk :: Error reading file : {}", e);
             }
         }
-        
+
         Disk {
             last_sector: 0,
             active: false,
-            disk_file: disk_file
+            disk_file: disk_file,
         }
     }
 
@@ -110,7 +109,8 @@ impl Disk {
         }
 
         disk.active = true;
-        disk.disk_file.seek(SeekFrom::Start((sector_number * SECTOR_SIZE) as u64))?;
+        disk.disk_file
+            .seek(SeekFrom::Start((sector_number * SECTOR_SIZE) as u64))?;
         let mut buffer = [0; SECTOR_SIZE as usize];
         disk.disk_file.read(&mut buffer)?;
         for byte in buffer {
@@ -142,7 +142,8 @@ impl Disk {
         }
 
         disk.active = true;
-        disk.disk_file.seek(SeekFrom::Start((sector_number * SECTOR_SIZE) as u64))?;
+        disk.disk_file
+            .seek(SeekFrom::Start((sector_number * SECTOR_SIZE) as u64))?;
         let mut i = 0;
         let mut buff = Vec::new();
         for value in data {
@@ -163,9 +164,7 @@ impl Disk {
     }
 }
 
-
-pub fn stupid_fct(buf : &[u8]){
-
+pub fn stupid_fct(buf: &[u8]) {
     println!("Size of unknown sized parameter buffer : {}", buf.len());
     for i in 0..buf.len() {
         println!("buf[{}] = {}", i, buf[i]);
@@ -184,7 +183,7 @@ mod test {
     #[test]
     #[serial]
     fn test_init_stupid_fct() {
-        let buffy: [u8 ; 6] = [1,2,3,4,5,6];
+        let buffy: [u8; 6] = [1, 2, 3, 4, 5, 6];
         stupid_fct(&buffy);
 
         //EN passant par une ref , on s'abstrait du besoin de connaitre la taille au moment de la compilation
@@ -214,11 +213,11 @@ mod test {
         data1.push(1 as u8);
 
         let mut data2: Vec<u8> = Vec::new();
-        
+
         Disk::write_request(&mut disk, 0, &mut data);
         Disk::write_request(&mut disk, 1, &mut data1);
         Disk::read_request(&mut disk, 1, &mut data2);
-        
+
         assert_eq!(data1, data2);
         assert_ne!(data, data1);
         assert_ne!(data, data2);

src/utility/bitmap.rs

@@ -0,0 +1,143 @@
+pub const BITS_IN_BYTE: usize = 8;
+pub const BITS_IN_WORD: usize = 32;
+
+use std::fs::File;
+use std::io::{Cursor, Write, Read};
+
+use crate::simulator::disk::SECTOR_SIZE;
+
+pub struct BitMap {
+    num_bits: usize,
+    num_words: usize,
+    map: Vec<u32>,
+}
+
+impl BitMap {
+
+    /// Initialize a bitmap with "nitems" bits, so that every bit is clear.
+    ///	it can be added somewhere on a list.
+    ///
+    /// ### Parameters
+    ///	- **nitems** is the number of bits in the bitmap.
+    ///----------------------------------------------------------------------
+    pub fn init_bitmap(n_items: usize) -> BitMap {
+        let mut tmp: Vec<u32>;
+        BitMap{
+            num_bits: n_items,
+            num_words: (n_items + SECTOR_SIZE as usize -1) / SECTOR_SIZE as usize,
+            map: tmp,
+        }
+    }
+
+    /// Set the "nth" bit in a bitmap.
+    /// ### Parameters
+    ///	- **which** is the number of the bit to be set.
+    pub fn mark(&mut self, which: usize) {
+        assert!(which >= 0 && which < self.num_bits);
+        self.map[which / BITS_IN_WORD] |= 1 << (which % BITS_IN_WORD);
+    }
+
+    /// return true if the "nth" bit is set.
+    /// 
+    /// ### Paramenters 
+    /// - **which** is the number of the bit to be tested.
+    pub fn test(&self, which: usize) -> bool {
+        assert!(which < self.num_bits);
+        (self.map[which / BITS_IN_WORD] & (1 << (which % BITS_IN_WORD))) != 0
+    }
+
+    /// Return the number of the first bit which is clear.
+    ///	As a side effect, set the bit (mark it as in use).
+    ///	(In other words, find and allocate a bit.)
+    /// If no bits are clear, return ERROR
+    pub fn find(&mut self) -> i32 {
+        for i in 0..self.num_bits {
+            if !self.test(i) {
+                self.mark(i);
+                return i as i32;
+            }
+        }
+        -1
+    }
+
+    /// Clear the "nth" bit in a bitmap.
+    /// ### Parameters
+    /// - **which** is the number of the bit to be cleared.
+    pub fn clear(&mut self, which: usize) {
+        assert!(which < self.num_bits, "index out of range");
+
+        let word_idx = which / BITS_IN_WORD;              
+        let bit_idx = which % BITS_IN_WORD;                 
+        self.map[word_idx] &= !(1 << bit_idx);    
+    }
+
+    /// Return the number of clear bits in the bitmap.
+    ///	(In other words, how many bits are unallocated?)
+    pub fn num_clear(&self) -> i32 {
+        let mut count = 0;
+        for i in 0..self.num_bits {
+            if !self.test(i) {
+                count += 1;
+            }
+        }
+        count
+    }
+
+    /// Print the contents of the bitmap, for debugging.
+    /// Could be done in a number of ways, but we just print the #'s of
+    ///	all the bits that are set in the bitmap.
+    pub fn print(&self) {
+        println!("Bitmap set:");
+        for i in 0..self.num_bits {
+            if self.test(i) {
+                print!("{}, ", i);
+            }
+        }
+        println!();
+    }
+
+    ///Initialize the contents of a bitmap from a Nachos file.
+    ///
+    /// ### Parameters
+    ///	- **file** is the place to read the bitmap from
+    pub fn fetch_from(&mut self, file_path: &str) -> std::io::Result<&Vec<u32>> {
+        // Ouvre le fichier en mode lecture seule
+        let mut file = File::open(file_path)?;
+
+        // Lit les octets du fichier dans un buffer
+        let mut buffer = vec![0; self.num_words * std::mem::size_of::<u32>()];
+        file.read_exact(&mut buffer)?;
+
+        // Convertit les octets en vecteur de u32
+        self.map = vec![0; self.num_words];
+        for i in 0..self.num_words {
+            let j = i * std::mem::size_of::<u32>();
+            let bytes = [
+                buffer[j], buffer[j+1], buffer[j+2], buffer[j+3]
+            ];
+            self.map[i] = u32::from_le_bytes(bytes);
+        }
+
+        Ok(&self.map)
+    }
+
+    /// Store the contents of a bitmap to a Nachos file.
+    ///
+    /// ### Paramenters
+    /// - **file** is the place to write the bitmap to
+    pub fn write_back(&mut self, file_path: &str) -> std::io::Result<()> {
+        // Encapsule le vecteur dans un std::io::Cursor pour l'utiliser comme un std::io::Write
+        let mut cursor = Cursor::new(Vec::<u8>::new());
+        for u32_val in self.map.as_mut_slice() {
+            cursor.write_all(&u32_val.to_le_bytes())?;
+        }
+
+        // Ouvre le fichier en mode écriture
+        let mut file = File::create(file_path)?;
+
+        // Écrit les données dans le fichier
+        file.write_all(&cursor.into_inner())?;
+
+        Ok(())
+    }
+}

src/utility/mod.rs

@@ -1 +1,2 @@
-pub mod list;
+pub mod list;
+pub mod bitmap;