* Global variables, needed for all threads but only initialized before any
 * FUSE threads are created
 */
const char *appfs_cachedir;
time_t appfs_boottime;
int appfs_fuse_started = 0;

/*
 * Global variables for AppFS caching
 */
pthread_mutex_t appfs_path_info_cache_mutex = PTHREAD_MUTEX_INITIALIZER;
int appfs_path_info_cache_size = 8209;
struct appfs_pathinfo *appfs_path_info_cache = NULL;

/*
 * AppFS Path Type:  Describes the type of path a given file is
 */
typedef enum {
	APPFS_PATHTYPE_INVALID,
	APPFS_PATHTYPE_DOES_NOT_EXIST,
	APPFS_PATHTYPE_FILE,
	APPFS_PATHTYPE_DIRECTORY,
	APPFS_PATHTYPE_SYMLINK,
	APPFS_PATHTYPE_SOCKET,
	APPFS_PATHTYPE_FIFO,
} appfs_pathtype_t;

			off_t size;
		} file;
		struct {
			off_t size;
			char source[256];
		} symlink;
	} typeinfo;

	/* Attributes used only for caching entries */
	char *_cache_path;
	uid_t _cache_uid;
};

/*
 * Create a new Tcl interpreter and completely initialize it
 */
static Tcl_Interp *appfs_create_TclInterp(char **error_string) {
	Tcl_Interp *interp;

	}

	retval = strdup(result->pw_dir);

	return(retval);
}















































































/*
 * Generate an inode for a given path.  The inode should be computed in such
 * a way that it is unlikely to be duplicated and remains the same for a given
 * file
 */
static long long appfs_get_path_inode(const char *path) {
	long long retval;

	}

	retval += 10;
	retval %= 4294967296ULL;

	return(retval);
}

/*
 * Cache Get Path Info lookups for speed
 */
static int appfs_get_path_info_cache_get(const char *path, uid_t uid, struct appfs_pathinfo *pathinfo) {
	unsigned int hash_idx;
	int pthread_ret;
	int retval;

	retval = 1;

	pthread_ret = pthread_mutex_lock(&appfs_path_info_cache_mutex);
	if (pthread_ret != 0) {
		APPFS_DEBUG("Unable to lock path_info cache mutex !");

		return(-1);
	}

	if (appfs_path_info_cache != NULL) {
		hash_idx = (appfs_get_path_inode(path) + uid) % appfs_path_info_cache_size;

		if (appfs_path_info_cache[hash_idx]._cache_path != NULL) {
			if (strcmp(appfs_path_info_cache[hash_idx]._cache_path, path) == 0 && appfs_path_info_cache[hash_idx]._cache_uid == uid) {
				retval = 0;

				memcpy(pathinfo, &appfs_path_info_cache[hash_idx], sizeof(*pathinfo));
				pathinfo->_cache_path = NULL;
			}
		}
	}

	pthread_ret = pthread_mutex_unlock(&appfs_path_info_cache_mutex);
	if (pthread_ret != 0) {
		APPFS_DEBUG("Unable to unlock path_info cache mutex !");

		return(-1);
	}

	if (retval == 0) {
		APPFS_DEBUG("Cache hit on %s", path);
	} else {
		APPFS_DEBUG("Cache miss on %s", path);
	}

	return(retval);
}

static void appfs_get_path_info_cache_add(const char *path, uid_t uid, struct appfs_pathinfo *pathinfo) {
	unsigned int hash_idx;
	int pthread_ret;

	pthread_ret = pthread_mutex_lock(&appfs_path_info_cache_mutex);
	if (pthread_ret != 0) {
		APPFS_DEBUG("Unable to lock path_info cache mutex !");

		return;
	}

	if (appfs_path_info_cache == NULL) {
		appfs_path_info_cache = calloc(appfs_path_info_cache_size, sizeof(*appfs_path_info_cache));
	}

	hash_idx = (appfs_get_path_inode(path) + uid) % appfs_path_info_cache_size;

	if (appfs_path_info_cache[hash_idx]._cache_path != NULL) {
		free(appfs_path_info_cache[hash_idx]._cache_path);
	}

	memcpy(&appfs_path_info_cache[hash_idx], pathinfo, sizeof(*pathinfo));

	appfs_path_info_cache[hash_idx]._cache_path = strdup(path);
	appfs_path_info_cache[hash_idx]._cache_uid  = uid;

	pthread_ret = pthread_mutex_unlock(&appfs_path_info_cache_mutex);
	if (pthread_ret != 0) {
		APPFS_DEBUG("Unable to unlock path_info cache mutex !");

		return;
	}
	return;
}

static void appfs_get_path_info_cache_rm(const char *path, uid_t uid) {
	unsigned int hash_idx;
	int pthread_ret;

	pthread_ret = pthread_mutex_lock(&appfs_path_info_cache_mutex);
	if (pthread_ret != 0) {
		APPFS_DEBUG("Unable to lock path_info cache mutex !");

		return;
	}

	if (appfs_path_info_cache != NULL) {
		hash_idx = (appfs_get_path_inode(path) + uid) % appfs_path_info_cache_size;

		if (appfs_path_info_cache[hash_idx]._cache_path != NULL) {
			free(appfs_path_info_cache[hash_idx]._cache_path);

			appfs_path_info_cache[hash_idx]._cache_path = NULL;
		}
	}

	pthread_ret = pthread_mutex_unlock(&appfs_path_info_cache_mutex);
	if (pthread_ret != 0) {
		APPFS_DEBUG("Unable to unlock path_info cache mutex !");

		return;
	}

	return;
}

static void appfs_get_path_info_cache_flush(uid_t uid, int new_size) {
	unsigned int idx;
	int pthread_ret;

	pthread_ret = pthread_mutex_lock(&appfs_path_info_cache_mutex);
	if (pthread_ret != 0) {
		APPFS_DEBUG("Unable to lock path_info cache mutex !");

		return;
	}

	if (appfs_path_info_cache != NULL) {
		for (idx = 0; idx < appfs_path_info_cache_size; idx++) {
			if (appfs_path_info_cache[idx]._cache_path != NULL) {
				if (uid != ((uid_t) -1)) {
					if (appfs_path_info_cache[idx]._cache_uid != uid) {
						continue;
					}
				}

				free(appfs_path_info_cache[idx]._cache_path);

				appfs_path_info_cache[idx]._cache_path = NULL;
			}
		}
	}

	if (uid == ((uid_t) -1)) {
		free(appfs_path_info_cache);

		appfs_path_info_cache = NULL;

		if (new_size != -1) {
			appfs_path_info_cache_size = new_size;
		}
	}

	pthread_ret = pthread_mutex_unlock(&appfs_path_info_cache_mutex);
	if (pthread_ret != 0) {
		APPFS_DEBUG("Unable to unlock path_info cache mutex !");

		return;
	}

	return;
}

/* Get information about a path, and optionally list children */
static int appfs_get_path_info(const char *path, struct appfs_pathinfo *pathinfo) {
	Tcl_Interp *interp;
	Tcl_Obj *attrs_dict, *attr_value;
	const char *attr_value_str;
	Tcl_WideInt attr_value_wide;
	int attr_value_int;
	static __thread Tcl_Obj *attr_key_type = NULL, *attr_key_perms = NULL, *attr_key_size = NULL, *attr_key_time = NULL, *attr_key_source = NULL, *attr_key_childcount = NULL, *attr_key_packaged = NULL;
	int cache_ret;
	int tcl_ret;

	cache_ret = appfs_get_path_info_cache_get(path, appfs_get_fsuid(), pathinfo);
	if (cache_ret == 0) {
		if (pathinfo->type == APPFS_PATHTYPE_DOES_NOT_EXIST) {
			return(-ENOENT);
		}

		if (pathinfo->type == APPFS_PATHTYPE_INVALID) {
			return(-EIO);
		}

		return(0);
	}

	interp = appfs_TclInterp();
	if (interp == NULL) {
		return(-EIO);
	}

	tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::getattr", path);
	if (tcl_ret != TCL_OK) {
		APPFS_DEBUG("::appfs::getattr(%s) failed.", path);
		APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp));

		pathinfo->type = APPFS_PATHTYPE_DOES_NOT_EXIST;

		appfs_get_path_info_cache_add(path, appfs_get_fsuid(), pathinfo);

		return(-ENOENT);
	}

	if (attr_key_type == NULL) {
		attr_key_type       = Tcl_NewStringObj("type", -1);
		attr_key_perms      = Tcl_NewStringObj("perms", -1);
		attr_key_size       = Tcl_NewStringObj("size", -1);

		if (tcl_ret == TCL_OK) {
			pathinfo->time = attr_value_wide;
		}
	} else {
		pathinfo->time = 0;
	}

	appfs_get_path_info_cache_add(path, appfs_get_fsuid(), pathinfo);

	return(0);
}

static char *appfs_prepare_to_create(const char *path) {
	Tcl_Interp *interp;
	const char *real_path;
	int tcl_ret;

	appfs_get_path_info_cache_flush(appfs_get_fsuid(), -1);

	interp = appfs_TclInterp();
	if (interp == NULL) {
		return(NULL);
	}

	tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::prepare_to_create", path);

			stbuf->st_size = 0;
			break;
		case APPFS_PATHTYPE_FIFO:
			stbuf->st_mode = S_IFIFO | 0555;
			stbuf->st_nlink = 1;
			stbuf->st_size = 0;
			break;
		case APPFS_PATHTYPE_DOES_NOT_EXIST:
			retval = -ENOENT;

			break;
		case APPFS_PATHTYPE_INVALID:
			retval = -EIO;

			break;
	}

	if (pathinfo.packaged) {
		stbuf->st_uid   = appfs_get_fsuid();
		stbuf->st_gid   = appfs_get_fsgid();
		stbuf->st_mode |= 0200;

	if ((fi->flags & (O_WRONLY|O_CREAT)) == (O_CREAT|O_WRONLY)) {
		/* The file will be created if it does not exist */
		if (gpi_ret != 0 && gpi_ret != -ENOENT) {
			return(gpi_ret);
		}

		mode = "create";

		/*
		 * We have to clear the cache here so that the number of
		 * links gets maintained on the parent directory
		 */
		appfs_get_path_info_cache_flush(appfs_get_fsuid(), -1);
	} else {
		/* The file must already exist */
		if (gpi_ret != 0) {
			return(gpi_ret);
		}

		mode = "";

	return(0);
}

static int appfs_fuse_close(const char *path, struct fuse_file_info *fi) {
	int close_ret;

	appfs_get_path_info_cache_rm(path, appfs_get_fsuid());

	close_ret = close(fi->fh);
	if (close_ret != 0) {
		return(-EIO);
	}

	return(0);
}

}

static int appfs_fuse_write(const char *path, const char *buf, size_t size, off_t offset, struct fuse_file_info *fi) {
	off_t lseek_ret;
	ssize_t write_ret;

	APPFS_DEBUG("Enter (path = %s, ...)", path);

	appfs_get_path_info_cache_rm(path, appfs_get_fsuid());

	lseek_ret = lseek(fi->fh, offset, SEEK_SET);
	if (lseek_ret != offset) {
		return(-EIO);
	}

	write_ret = write(fi->fh, buf, size);

	APPFS_DEBUG("Enter (path = %s, ...)", path);

	real_path = appfs_localpath(path);
	if (real_path == NULL) {
		return(-EIO);
	}

	appfs_get_path_info_cache_rm(path, appfs_get_fsuid());

	appfs_simulate_user_fs_enter();

	truncate_ret = truncate(real_path, size);

	appfs_simulate_user_fs_leave();

	free(real_path);

	if (truncate_ret != 0) {
		return(errno * -1);
	}

	return(0);
}

static int appfs_fuse_unlink_rmdir(const char *path) {
	Tcl_Interp *interp;
	int tcl_ret;

	APPFS_DEBUG("Enter (path = %s, ...)", path);

	appfs_get_path_info_cache_flush(appfs_get_fsuid(), -1);

	interp = appfs_TclInterp();
	if (interp == NULL) {
		return(-EIO);
	}

	tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::unlinkpath", path);

}

static int appfs_fuse_mkdir(const char *path, mode_t mode) {
	char *real_path;
	int mkdir_ret;

	APPFS_DEBUG("Enter (path = %s, ...)", path);


	real_path = appfs_prepare_to_create(path);
	if (real_path == NULL) {
		return(-EIO);
	}

	appfs_simulate_user_fs_enter();

static int appfs_fuse_chmod(const char *path, mode_t mode) {
	Tcl_Interp *interp;
	const char *real_path;
	int tcl_ret, chmod_ret;

	APPFS_DEBUG("Enter (path = %s, ...)", path);

	appfs_get_path_info_cache_rm(path, appfs_get_fsuid());

	interp = appfs_TclInterp();
	if (interp == NULL) {
		return(-EIO);
	}

	tcl_ret = appfs_Tcl_Eval(interp, 3, "::appfs::openpath", path, "write");

}

/*
 * AppFSd Package for Tcl:
 *         Bridge for I/O operations to request information about the current
 *         transaction
 */
/*
 * Tcl interface to get the home directory for the user making the "current"
 * FUSE I/O request
 */
static int tcl_appfs_get_homedir(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
	char *homedir;
	Tcl_Obj *homedir_obj;
	uid_t fsuid;
	static __thread Tcl_Obj *last_homedir_obj = NULL;
	static __thread uid_t last_fsuid = -1;

        if (objc != 1) {
                Tcl_WrongNumArgs(interp, 1, objv, NULL);
                return(TCL_ERROR);
        }

	fsuid = appfs_get_fsuid();

	if (fsuid == last_fsuid && last_homedir_obj != NULL) {
		homedir_obj = last_homedir_obj;
	} else {
		homedir = appfs_get_homedir(appfs_get_fsuid());

		if (homedir == NULL) {
			return(TCL_ERROR);
		}

		homedir_obj = Tcl_NewStringObj(homedir, -1);

		free(homedir);

		if (last_homedir_obj != NULL) {
			Tcl_DecrRefCount(last_homedir_obj);
		}

		last_homedir_obj = homedir_obj;
		last_fsuid = fsuid;

		Tcl_IncrRefCount(last_homedir_obj);
	}

       	Tcl_SetObjResult(interp, homedir_obj);

        return(TCL_OK);
}

static int tcl_appfs_simulate_user_fs_enter(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
	appfs_simulate_user_fs_enter();

	return(TCL_OK);
}

static int tcl_appfs_simulate_user_fs_leave(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
	appfs_simulate_user_fs_leave();

	return(TCL_OK);
}

static int tcl_appfs_get_fsuid(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
	uid_t fsuid;

	fsuid = appfs_get_fsuid();

       	Tcl_SetObjResult(interp, Tcl_NewWideIntObj(fsuid));

	return(TCL_OK);
}

static int tcl_appfs_get_fsgid(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
	gid_t fsgid;

	fsgid = appfs_get_fsgid();

       	Tcl_SetObjResult(interp, Tcl_NewWideIntObj(fsgid));

	return(TCL_OK);
}

static int tcl_appfs_get_path_info_cache_flush(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
	int tcl_ret;
	int new_size;

	new_size = -1;

	if (objc == 2) {
		tcl_ret = Tcl_GetIntFromObj(interp, objv[1], &new_size);
		if (tcl_ret != TCL_OK) {
			return(tcl_ret);
		}
	} else if (objc > 2 || objc < 1) {
                Tcl_WrongNumArgs(interp, 1, objv, "?new_cache_size?");
		return(TCL_ERROR);
	}

	appfs_get_path_info_cache_flush(-1, new_size);

	return(TCL_OK);
}

static int Appfsd_Init(Tcl_Interp *interp) {
#ifdef USE_TCL_STUBS
	if (Tcl_InitStubs(interp, TCL_VERSION, 0) == 0L) {
		return(TCL_ERROR);
	}
#endif

	Tcl_CreateObjCommand(interp, "appfsd::get_homedir", tcl_appfs_get_homedir, NULL, NULL);
	Tcl_CreateObjCommand(interp, "appfsd::get_fsuid", tcl_appfs_get_fsuid, NULL, NULL);
	Tcl_CreateObjCommand(interp, "appfsd::get_fsgid", tcl_appfs_get_fsgid, NULL, NULL);
	Tcl_CreateObjCommand(interp, "appfsd::simulate_user_fs_enter", tcl_appfs_simulate_user_fs_enter, NULL, NULL);
	Tcl_CreateObjCommand(interp, "appfsd::simulate_user_fs_leave", tcl_appfs_simulate_user_fs_leave, NULL, NULL);
	Tcl_CreateObjCommand(interp, "appfsd::get_path_info_cache_flush", tcl_appfs_get_path_info_cache_flush, NULL, NULL);

	Tcl_PkgProvide(interp, "appfsd", "1.0");

	return(TCL_OK);
}

/*