/*
** Supprime un bloc de la liste des blocs libres
*/
int remove_free_block(disk_id id, uint32_t id_description_block){
/* Mise en mémoire du block de description */
block description_block;
description_block.block_block = malloc(1024);
if(read_block(id,description_block,id_description_block).error_id==1){
fprintf(stderr, "Erreur lors de la lecture du block.\n");
return 1;
}
/* Mise en mémoire de l'id du block à remove */
uint32_t id_block_to_remove = get_first_free_block(id,id_description_block);
/* Overwrite de la valeur de TTTFS_VOLUME_FREE_BLOCK_COUNT dans le block de description en mémoire */
write_inblock(description_block,3,read_inblock(3,description_block)-1);
/* Overwrite de la valeur de TTTFS_VOLUME_FIRST_FREE_BLOCK dans le block de description en mémoire */
block remove_block;
remove_block.block_block = malloc(1024);
read_block(id,remove_block,id_description_block+id_block_to_remove);
write_inblock(description_block,4,read_inblock(255,remove_block));
/* Overwrite du description_block en mémoire sur le disk */
write_block(id,description_block,id_description_block);
/* Mise en mémoire du block_to_remove */
block block_to_remove;
block_to_remove.block_block = malloc(1024);
if(read_block(id,block_to_remove,id_block_to_remove).error_id==1){
fprintf(stderr, "Erreur lors de la lecture du block.\n");
return 1;
}
/* Overwrite de la valeur du next_free_block dans le last_free_block en mémoire */
write_inblock(block_to_remove,255,0);
/* Overwrite du last_free_block sur le disk */
write_block(id,block_to_remove,id_block_to_remove);
return 0;
}
/*
* Does the actual creation of a file. Mode and dev can be ignored.
*
*/
static int cs1550_mknod(const char *path, mode_t mode, dev_t dev)
{
(void) mode;
(void) dev;
char directory[MAX_FILENAME + 1]; //name of directory we are looking for
char filename[MAX_FILENAME + 1]; //name of file we are looking for
char extension[MAX_EXTENSION + 1]; //file extension we are looking for
int res = 0;
meta_entry attribute = find_correct_directory(path);
sscanf(path, "/%[^/]/%[^.].%s", directory, filename, extension); //tokenizes and stores the strings for the directory we are looking for
if( attribute.slash_count == 1 ) //under root, do not give permission
{
res = -EPERM;
}
else if( strlen(filename) > 8 || strlen(extension) > 3 ) //name length is too long
{
res = -ENAMETOOLONG;
}
else if( attribute.file_index > -1) //is already a file
{
res = -EEXIST;
}
else //create file
{
cs1550_directory_entry directory_entry = get_directory_entry( attribute.index_of_directory );
strcpy(directory_entry.files[ directory_entry.nFiles ].fname, filename); //put filename in array index
strcpy(directory_entry.files[ directory_entry.nFiles ].fext, extension); //put extension in array index
// directory_entry.files[ directory_entry.nFiles ].fsize = 512; //size of block
directory_entry.files[ directory_entry.nFiles ].fsize = 0; //size of block
directory_entry.files[ directory_entry.nFiles ].nStartBlock = get_first_free_block(); //gets the first free block
directory_entry.nFiles = directory_entry.nFiles++; //increment the amount of files
write_directory_entry( directory_entry, attribute.index_of_directory ); //write the directory entry
}
return res;
}
void add_default_directories(ino iNode, ino parentiNode) {
int freeBlockNumber = get_first_free_block();
add_data_block_to_inode(iNode, freeBlockNumber);
char directoryDataBlock[BLOCK_SIZE];
ReadBlock(6 + iNode - 1, directoryDataBlock);
DirEntry *directory = (DirEntry *)directoryDataBlock;
strcpy(directory[0].Filename, ".");
directory[0].iNode = iNode;
add_size_to_inode_size(sizeof(directory[0]), iNode);
strcpy(directory[1].Filename, "..");
directory[1].iNode = parentiNode;
add_size_to_inode_size(sizeof(directory[1]), iNode);
WriteBlock(6 + iNode - 1, directoryDataBlock);
}
/*
** Renvoie l'id du dernier block libre de la partition
*/
uint32_t get_last_free_block(disk_id id, uint32_t id_description_block){
uint32_t prev_free_block = get_first_free_block(id,id_description_block);
uint32_t next_free_block = 0;
block description_block;
block tmp_block;
description_block.block_block = malloc(1024);
tmp_block.block_block = malloc(1024);
read_block(id,description_block,id_description_block);
read_block(id,tmp_block,prev_free_block);
next_free_block = read_inblock(1023,tmp_block)+ id_description_block;
while(next_free_block != prev_free_block){
prev_free_block = next_free_block;
read_block(id,tmp_block,prev_free_block);
next_free_block = read_inblock(1023,tmp_block)+ id_description_block;
}
free(description_block.block_block);
free(tmp_block.block_block);
return next_free_block;
}
void assign_free_datablock(ino pFilenameiNode) {
int freeDataBlockNumber = get_first_free_block();
char freeDataBlock[BLOCK_SIZE];
iNodeEntry *iNodes;
if (pFilenameiNode < 16) {
ReadBlock(4, freeDataBlock);
iNodes = (iNodeEntry *)freeDataBlock;
iNodes[pFilenameiNode].Block[0] = freeDataBlockNumber;
iNodes[pFilenameiNode].iNodeStat.st_blocks = 1;
WriteBlock(4, freeDataBlock);
} else {
ReadBlock(5, freeDataBlock);
iNodes = (iNodeEntry *)freeDataBlock;
iNodes[pFilenameiNode - 16].Block[0] = freeDataBlockNumber;
iNodes[pFilenameiNode].iNodeStat.st_blocks = 1;
WriteBlock(5, freeDataBlock);
}
}
