Return a new download.

Return a procedure that can be passed to 'build-event-output-port'. That procedure computes the new build status upon each event and calls ON-CHANGE:

(ON-CHANGE event status new-status)

ON-CHANGE can display the build status, build events, etc.

Print information about EVENT and STATUS to PORT. When COLORIZE? is true, produce colorful output. When PRINT-LOG? is true, display the build log in addition to build events. When PRINT-URLS? is true, display the URL of substitutes being downloaded.

Return an output port for use as 'current-build-output-port' that calls PROC with its current state value, initialized with SEED, on every build event. Build events passed to PROC are tuples corresponding to the "build traces" produced by the daemon:

(build-started "/gnu/store/...-foo.drv" ...) (substituter-started "/gnu/store/...-foo" ...)

and so on.

The second return value is a thunk to retrieve the current state.

Given EVENT, a tuple like (build-started "/gnu/store/...-foo.drv" ...), compute a new status based on STATUS.

Reset the modification time on FILE and on all the files it contains, if it's a directory. Canonicalize file permissions unless PRESERVE-PERMISSIONS? is true.

Registers this stuff in DB. PATH is the store item to register and REFERENCES is the list of store items PATH refers to; DERIVER is the '.drv' that produced PATH, HASH is the base16-encoded Nix sha256 hash of PATH (prefixed with "sha256:"), and NAR-SIZE is the size in bytes PATH after being converted to nar form. TIME is the registration time to be recorded in the database or #f, meaning "right now".

Every store item in REFERENCES must already be registered.

Return the store database file name, taking PREFIX and STATE-DIRECTORY into account when provided.

Pass PROC a database record corresponding to FILE. If FILE doesn't exist, create it and initialize it as a new database. Unless WAL-MODE? is set to #f, set journal_mode=WAL.

If PATH exists in the 'ValidPaths' table, return its numerical identifier. Otherwise, return #f.

Register all of ITEMS, a list of <store-info> records as returned by 'read-reference-graph', in DB. ITEMS must be in topological order (with leaves first.) REGISTRATION-TIME must be the registration time to be recorded in the database; #f means "now". Write a progress report to LOG-PORT. All of ITEMS must be protected from GC and locked during execution of this, typically by adding them as temp-roots.