restore.v

1//! Writing a tree back onto disk.2//!3//! A restore writes exactly the target's files and deletes the tracked files4//! the target does not have. Ignored paths are never touched, and every file5//! lands through a temp file and a rename, so an interrupted restore leaves a6//! readable tree rather than half-written files.78module snapshot910import os11import src.storage1213pub struct RestoreReport {14pub:15	written int16	removed int17}1819// restore_files writes exactly `target` into the working tree and deletes the20// paths in `remove` (tracked files the target does not have). Ignored paths are21// never touched — not written, not deleted — even if a caller asks. Every file22// lands through a temp file and a rename, so an interrupted restore leaves a23// readable tree rather than half-written files.24pub fn restore_files(store &storage.Store, root string, ig Ignore, target []FileEntry, remove []string) !RestoreReport {25	mut wanted := map[string]bool{}26	for entry in target {27		wanted[entry.path] = true28	}29	mut removed := 030	for path in remove {31		full := os.join_path(root, path)32		if !os.is_file(full) || ig.matches(path, false) || path in wanted {33			continue34		}35		os.rm(full)!36		removed++37		prune_empty_dirs(root, os.dir(full))38	}39	for entry in target {40		data := store.get_object(entry.hash)!41		write_file(os.join_path(root, entry.path), data, entry.executable)!42	}43	return RestoreReport{44		written: target.len45		removed: removed46	}47}4849fn write_file(path string, data []u8, executable bool) ! {50	os.mkdir_all(os.dir(path), os.MkdirParams{})!51	tmp := '${path}.koh-tmp-${os.getpid()}'52	os.write_file_array(tmp, data)!53	mode := if executable { 0o755 } else { 0o644 }54	os.chmod(tmp, mode)!55	os.mv(tmp, path, os.MvParams{})!56}5758// prune_empty_dirs clears directories a restore emptied, never the repo root.59fn prune_empty_dirs(root string, dir string) {60	mut current := dir61	for current.len > root.len && current.starts_with(root) {62		if (os.ls(current) or { return }).len > 0 {63			return64		}65		os.rmdir(current) or { return }66		current = os.dir(current)67	}68}