Function openWriteBufferSync

packages/dofs/src/fs/writeFile.ts:521–541

(db: Database, path: string)

// buffer instead of the SQLite chunk/blob store. Release commits
// the bytes back to chunks.
export function openWriteBufferSync(db: Database, path: string): void {
  const { path: canonical } = canonicalizePath(path);
  const pending = getPendingWriteBufferByPath(db, canonical);
  if (pending !== undefined) {
    pending.openCount += 1;
    return;
  }
  const { inode, mode } = resolveFileInode(db, path);
  const existing = getWriteBuffer(db, inode);
  if (existing !== undefined) {
    existing.openCount += 1;
    return;
  }
  setWriteBuffer(db, inode, {
    buf: new Uint8Array(0),
    size: 0,
    dirty: false,
    openCount: 1,
    mode,
  });
}

// Create a new file lazily: stash a pending-create write buffer
// keyed by path, without touching SQL until release. createFileSync