memfs
Version:
In-memory file-system with Node's fs API.
287 lines • 8.37 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.Node = void 0;
const fanout_1 = require("thingies/lib/fanout");
const process_1 = require("../process");
const buffer_1 = require("../vendor/node/internal/buffer");
const constants_1 = require("../constants");
const { S_IFMT, S_IFDIR, S_IFREG, S_IFLNK, S_IFCHR } = constants_1.constants;
const getuid = () => process_1.default.getuid?.() ?? 0;
const getgid = () => process_1.default.getgid?.() ?? 0;
const EMPTY_BUFFER = (0, buffer_1.bufferAllocUnsafe)(0);
/**
* Node in a file system (like i-node, v-node).
*/
class Node {
constructor(ino, mode = 0o666) {
this.changes = new fanout_1.FanOut();
// User ID and group ID.
this._uid = getuid();
this._gid = getgid();
this._atime = new Date();
this._mtime = new Date();
this._ctime = new Date();
this.buf = EMPTY_BUFFER;
/** Total allocated memory capacity for this node. */
this.capacity = 0;
/** Actually used bytes to store content. */
this.size = 0;
this.rdev = 0;
// Number of hard links pointing at this Node.
this._nlink = 1;
this.mode = mode;
this.ino = ino;
}
set ctime(ctime) {
this._ctime = ctime;
}
get ctime() {
return this._ctime;
}
set uid(uid) {
this._uid = uid;
this.ctime = new Date();
}
get uid() {
return this._uid;
}
set gid(gid) {
this._gid = gid;
this.ctime = new Date();
}
get gid() {
return this._gid;
}
set atime(atime) {
this._atime = atime;
}
get atime() {
return this._atime;
}
set mtime(mtime) {
this._mtime = mtime;
this.ctime = new Date();
}
get mtime() {
return this._mtime;
}
get perm() {
return this.mode & ~S_IFMT;
}
set perm(perm) {
this.mode = (this.mode & S_IFMT) | (perm & ~S_IFMT);
this.ctime = new Date();
}
set nlink(nlink) {
this._nlink = nlink;
this.ctime = new Date();
}
get nlink() {
return this._nlink;
}
getString(encoding = 'utf8') {
this.atime = new Date();
return this.getBuffer().toString(encoding);
}
setString(str) {
this._setBuf((0, buffer_1.bufferFrom)(str, 'utf8'));
}
getBuffer() {
this.atime = new Date();
if (!this.buf)
this.buf = (0, buffer_1.bufferAllocUnsafe)(0);
return (0, buffer_1.bufferFrom)(this.buf.subarray(0, this.size)); // Return a copy of used portion.
}
setBuffer(buf) {
const copy = (0, buffer_1.bufferFrom)(buf); // Creates a copy of data.
this._setBuf(copy);
}
_setBuf(buf) {
const size = buf.length;
this.buf = buf;
this.capacity = size;
this.size = size;
this.touch();
}
getSize() {
return this.size;
}
setModeProperty(property) {
this.mode = property;
}
isFile() {
return (this.mode & S_IFMT) === S_IFREG;
}
isDirectory() {
return (this.mode & S_IFMT) === S_IFDIR;
}
isSymlink() {
// return !!this.symlink;
return (this.mode & S_IFMT) === S_IFLNK;
}
isCharacterDevice() {
return (this.mode & S_IFMT) === S_IFCHR;
}
makeSymlink(symlink) {
this.mode = S_IFLNK | 0o666;
this.symlink = symlink;
}
write(buf, off = 0, len = buf.length, pos = 0) {
const bufLength = buf.length;
if (off + len > bufLength)
len = bufLength - off;
if (len <= 0)
return 0;
const requiredSize = pos + len;
if (requiredSize > this.capacity) {
let newCapacity = Math.max(this.capacity * 2, 64);
while (newCapacity < requiredSize)
newCapacity *= 2;
const newBuf = (0, buffer_1.bufferAllocUnsafe)(newCapacity);
if (this.size > 0)
this.buf.copy(newBuf, 0, 0, this.size);
this.buf = newBuf;
this.capacity = newCapacity;
}
if (pos > this.size)
this.buf.fill(0, this.size, pos);
buf.copy(this.buf, pos, off, off + len);
if (requiredSize > this.size)
this.size = requiredSize;
this.touch();
return len;
}
/**
* Read data from the file.
*
* @param buf Buffer to read data into.
* @param off Offset int the `buf` where to start writing data.
* @param len How many bytes to read. Equals to `buf.byteLength` by default.
* @param pos Position offset in file where to start reading. Defaults to `0`.
* @returns Returns the number of bytes read.
*/
read(buf, off = 0, len = buf.byteLength, pos = 0) {
this.atime = new Date();
if (pos >= this.size)
return 0;
let actualLen = len;
if (actualLen > buf.byteLength)
actualLen = buf.byteLength;
if (actualLen + pos > this.size)
actualLen = this.size - pos;
if (actualLen <= 0)
return 0;
const buf2 = buf instanceof buffer_1.Buffer ? buf : buffer_1.Buffer.from(buf.buffer, buf.byteOffset, buf.byteLength);
this.buf.copy(buf2, off, pos, pos + actualLen);
return actualLen;
}
truncate(len = 0) {
if (!len) {
this.buf = EMPTY_BUFFER;
this.capacity = 0;
this.size = 0;
this.touch();
return;
}
if (len <= this.size)
this.size = len;
else {
if (len > this.capacity) {
let newCapacity = Math.max(this.capacity * 2, 64);
while (newCapacity < len)
newCapacity *= 2;
const buf = (0, buffer_1.bufferAllocUnsafe)(newCapacity);
if (this.size > 0)
this.buf.copy(buf, 0, 0, this.size);
buf.fill(0, this.size, len);
this.buf = buf;
this.capacity = newCapacity;
}
else
this.buf.fill(0, this.size, len);
this.size = len;
}
this.touch();
}
chmod(perm) {
this.mode = (this.mode & S_IFMT) | (perm & ~S_IFMT);
this.touch();
}
chown(uid, gid) {
this.uid = uid;
this.gid = gid;
this.touch();
}
touch() {
this.mtime = new Date();
this.changes.emit(['modify']);
}
canRead(uid = getuid(), gid = getgid()) {
if (this.perm & 4 /* S.IROTH */) {
return true;
}
if (gid === this.gid) {
if (this.perm & 32 /* S.IRGRP */) {
return true;
}
}
if (uid === this.uid) {
if (this.perm & 256 /* S.IRUSR */) {
return true;
}
}
return false;
}
canWrite(uid = getuid(), gid = getgid()) {
if (this.perm & 2 /* S.IWOTH */) {
return true;
}
if (gid === this.gid) {
if (this.perm & 16 /* S.IWGRP */) {
return true;
}
}
if (uid === this.uid) {
if (this.perm & 128 /* S.IWUSR */) {
return true;
}
}
return false;
}
canExecute(uid = getuid(), gid = getgid()) {
if (this.perm & 1 /* S.IXOTH */) {
return true;
}
if (gid === this.gid) {
if (this.perm & 8 /* S.IXGRP */) {
return true;
}
}
if (uid === this.uid) {
if (this.perm & 64 /* S.IXUSR */) {
return true;
}
}
return false;
}
del() {
this.changes.emit(['delete']);
}
toJSON() {
return {
ino: this.ino,
uid: this.uid,
gid: this.gid,
atime: this.atime.getTime(),
mtime: this.mtime.getTime(),
ctime: this.ctime.getTime(),
perm: this.perm,
mode: this.mode,
nlink: this.nlink,
symlink: this.symlink,
data: this.getString(),
};
}
}
exports.Node = Node;
//# sourceMappingURL=Node.js.map