File storage
File storage is (surprise!) intended for storing files (images, videos, audio, etc.).
flowchart
subgraph File storage
subgraph FS VLS
fpgs["Page files \n(many)"]
fpg_idxs["Page indexes \n(for each page)"]
ftoc["ToC"]
ftoc --> fpg_idxs
fpg_idxs --> fpgs
end
fls["Files \n(many)"]
fpgs --> fls
end
Example filesystem structure:
root
|- vls
|- toc.dat
|- idx0.dat
|- page0.dat
|- idx1.dat
|- files
|- someFileName.someExt
|- someFileName.someExt
|- someFileName.someExtFile storage consists of a separate VLS and a collection of files.
File storage assigns each file an id and its VLS stores mapping from ids to filenames.
File roles & terminology
Please, refer to VLS specification.
File structure
Please, refer to VLS specification.
Operations
Add file
flowchart
start([Start]) --> savefile[Save file in files directory]
savefile --> savepath[Save path in VLS]
savepath --> e([Return new id from VLS, end])
Get file
flowchart
start([Start]) --> getid[Get path by id in VLS]
getid --> ifnone>If VLS returned none]
ifnone -->|Yes| enone([Return none, end])
ifnone -->|No| e([Return path, end])
Remove file
flowchart
start([Start]) --> getid[Get path by id in VLS]
getid --> ifnone>If VLS returned none]
ifnone -->|Yes| enone([Return, end])
ifnone -->|No| delvls[Delete record from VLS]
delvls --> delfile[Delete actual file]
delfile --> e([End])