tmpfs mknod

tmpfs_node *tmpfs_getnod(tmpfs_node *parent, char *path) {

    if (!path[0]) return parent;

    tmpfs_node *cnode = parent->sub.first; // sub directories.

    // Loop on all sub directories:
    while (cnode != (tmpfs_node *) NULLNODE) {
        // check name:
        unsigned int i = 0;
        char *name1 = &path[1]; // skip '/'.
        char *name2 = cnode->name;

        // loop on characters (compare name1 with name2)
        while (name1[i] && name1[i] != '/' && name2[i] && name1[i] == name2[i]) i++;

        // check comparison results:
        if (((!name1[i]) || name1[i] == '/') && (!name2[i])) {
            if (name1[i] == '/' && (cnode->mode & 0xF000) != MODE_TYPE_DIR)
                    break; // not dir.
            return tmpfs_getnod(cnode, &name1[i]);
        }

        cnode = cnode->next;
    }

    // not found:
    return (tmpfs_node *) NULLNODE;
}

int tmpfs_mknod(unsigned int subid, char *path, unsigned int psize, mode_t mode, void *data) {

    tmpfs_node *rootdir = tmpfs_rootdir[subid];
    if (rootdir == (tmpfs_node *) 0) return -1;

    // 1- check if "path" already exists:
    if (tmpfs_getnod(rootdir, path) != (tmpfs_node *) NULLNODE)
        return -1; // file exists.

    // 2- Get parent:
    unsigned int i = psize;
    while(path[--i] != '/'); // make path[i] refers to the end of parent path.
    path[i] = 0;
    tmpfs_node *parent = tmpfs_getnod(rootdir, path);
    path[i] = '/';
    if (parent == (tmpfs_node *) NULLNODE) return -1; // invalid path.
    if ((parent->mode & 0xF000) != MODE_TYPE_DIR) return -1; // parent not directory.

    // 3- make node:
    tmpfs_node *nnode = (tmpfs_node *) kmalloc(sizeof(tmpfs_node));
    unsigned int namesize = psize - i; // with \0 in account.
    nnode->name = (char *) kmalloc(namesize);
    for (unsigned int j = 0; j < namesize; j++) nnode->name[j] = path[++i];
    nnode->mode = mode;
    nnode->size = 0;
    linkedlist_init((linkedlist *) &(nnode->sub));
    linkedlist_init((linkedlist *) &(nnode->blocks));

    // 4- add the node to the parent directory:
    linkedlist_add((linkedlist *) &(parent->sub), (linknode *) nnode);

    // 5- return:
    return 0;
}