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code_moniker_workspace/
cache.rs

1// code-moniker: ignore-file[smell-harmonious-method-size]
2// TODO(smell): keep CacheKey as a narrow cache-identity value object; revisit this suppression if hashing, path metadata, or graph IO responsibilities grow further.
3use std::fs;
4use std::hash::{Hash, Hasher};
5use std::io::{self, Write};
6use std::path::{Path, PathBuf};
7use std::sync::atomic::{AtomicU64, Ordering};
8use std::time::UNIX_EPOCH;
9
10use code_moniker_core::core::code_graph::CodeGraph;
11use code_moniker_core::core::code_graph::encoding::{self, LAYOUT_VERSION};
12use rustc_hash::FxHasher;
13
14use crate::extract;
15use code_moniker_core::lang::Lang;
16
17const CACHE_MAGIC: u32 = 0xC0DE_2106;
18// Bump when cached graph semantics change, even if the binary layout stays stable.
19const CACHE_FORMAT_VERSION: u32 = 7;
20const OFF_MAGIC: usize = 0;
21const OFF_FORMAT: usize = 4;
22const OFF_MTIME: usize = 8;
23const OFF_SIZE: usize = 16;
24const OFF_ANCHOR: usize = 24;
25const OFF_CONTEXT: usize = 32;
26const OFF_PATH_LEN: usize = 40;
27const HEADER_FIXED: usize = OFF_PATH_LEN + 4;
28
29static TMP_NONCE: AtomicU64 = AtomicU64::new(0);
30
31#[derive(Clone, Debug)]
32pub struct CacheKey {
33	pub abs_path: PathBuf,
34	pub mtime: u64,
35	pub size: u64,
36	pub anchor_hash: u64,
37	pub context_hash: u64,
38}
39
40impl CacheKey {
41	#[cfg(test)]
42	pub fn from_path(path: &Path, anchor: &Path) -> io::Result<Self> {
43		Self::from_path_with_context(path, anchor, &extract::Context::default())
44	}
45
46	pub fn from_path_with_context(
47		path: &Path,
48		anchor: &Path,
49		ctx: &extract::Context,
50	) -> io::Result<Self> {
51		let abs_path = path.canonicalize()?;
52		let meta = fs::metadata(&abs_path)?;
53		let mtime = meta
54			.modified()?
55			.duration_since(UNIX_EPOCH)
56			.map(|d| d.as_nanos() as u64)
57			.unwrap_or(0);
58		Ok(Self {
59			abs_path,
60			mtime,
61			size: meta.len(),
62			anchor_hash: hash_path(anchor),
63			context_hash: hash_context(ctx),
64		})
65	}
66
67	fn path_hash(&self) -> u64 {
68		hash_path(&self.abs_path)
69	}
70
71	fn full_path(&self, root: &Path) -> PathBuf {
72		root.join(format!("v{LAYOUT_VERSION}_{CACHE_FORMAT_VERSION}"))
73			.join(self.shard())
74			.join(self.filename())
75	}
76
77	fn filename(&self) -> String {
78		format!(
79			"{:016x}_{:016x}_{:016x}.bin",
80			self.path_hash(),
81			self.anchor_hash,
82			self.context_hash,
83		)
84	}
85
86	fn shard(&self) -> String {
87		format!("{:02x}", (self.path_hash() & 0xff) as u8)
88	}
89
90	fn abs_path_bytes(&self) -> &[u8] {
91		path_bytes(&self.abs_path)
92	}
93}
94
95pub fn load(cache_dir: &Path, key: &CacheKey) -> Option<CodeGraph> {
96	let path = key.full_path(cache_dir);
97	let bytes = fs::read(&path).ok()?;
98	let body = validate_header(&bytes, key)?;
99	match encoding::decode(body) {
100		Ok(g) => Some(g),
101		Err(e) => {
102			eprintln!(
103				"code-moniker: cache decode failed at {} ({e}); ignoring",
104				path.display(),
105			);
106			None
107		}
108	}
109}
110
111pub fn store(cache_dir: &Path, key: &CacheKey, graph: &CodeGraph) {
112	let _ = try_store(cache_dir, key, graph);
113}
114
115fn try_store(cache_dir: &Path, key: &CacheKey, graph: &CodeGraph) -> io::Result<()> {
116	let path = key.full_path(cache_dir);
117	if let Some(parent) = path.parent() {
118		fs::create_dir_all(parent)?;
119	}
120	let body = encoding::encode(graph)
121		.map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e.to_string()))?;
122	let path_bytes = key.abs_path_bytes();
123	let mut buf = Vec::with_capacity(HEADER_FIXED + path_bytes.len() + body.len());
124	buf.extend_from_slice(&CACHE_MAGIC.to_le_bytes());
125	buf.extend_from_slice(&CACHE_FORMAT_VERSION.to_le_bytes());
126	buf.extend_from_slice(&key.mtime.to_le_bytes());
127	buf.extend_from_slice(&key.size.to_le_bytes());
128	buf.extend_from_slice(&key.anchor_hash.to_le_bytes());
129	buf.extend_from_slice(&key.context_hash.to_le_bytes());
130	buf.extend_from_slice(&(path_bytes.len() as u32).to_le_bytes());
131	buf.extend_from_slice(path_bytes);
132	buf.extend_from_slice(&body);
133
134	let nonce = TMP_NONCE.fetch_add(1, Ordering::Relaxed);
135	let tmp = path.with_extension(format!("tmp.{}.{nonce}", std::process::id()));
136	let write_result = (|| -> io::Result<()> {
137		let mut f = fs::File::create(&tmp)?;
138		f.write_all(&buf)?;
139		f.sync_data()?;
140		Ok(())
141	})();
142	if let Err(e) = write_result {
143		let _ = fs::remove_file(&tmp);
144		return Err(e);
145	}
146	fs::rename(&tmp, &path)
147}
148
149#[allow(dead_code)]
150pub fn load_or_extract(
151	path: &Path,
152	anchor: &Path,
153	lang: Lang,
154	cache_dir: Option<&Path>,
155	ctx: &extract::Context,
156) -> Option<(CodeGraph, Option<String>)> {
157	load_or_extract_result(path, anchor, lang, cache_dir, ctx).ok()
158}
159
160pub fn load_or_extract_result(
161	path: &Path,
162	anchor: &Path,
163	lang: Lang,
164	cache_dir: Option<&Path>,
165	ctx: &extract::Context,
166) -> io::Result<(CodeGraph, Option<String>)> {
167	if let Some(dir) = cache_dir
168		&& let Ok(key) = CacheKey::from_path_with_context(path, anchor, ctx)
169	{
170		if let Some(g) = load(dir, &key) {
171			return Ok((g, None));
172		}
173		let source = fs::read_to_string(path)?;
174		let graph = extract::extract_with(lang, &source, anchor, ctx);
175		store(dir, &key, &graph);
176		return Ok((graph, Some(source)));
177	}
178	let source = fs::read_to_string(path)?;
179	let graph = extract::extract_with(lang, &source, anchor, ctx);
180	Ok((graph, Some(source)))
181}
182
183fn validate_header<'a>(bytes: &'a [u8], key: &CacheKey) -> Option<&'a [u8]> {
184	if bytes.len() < HEADER_FIXED {
185		return None;
186	}
187	let magic = u32::from_le_bytes(bytes[OFF_MAGIC..OFF_FORMAT].try_into().ok()?);
188	if magic != CACHE_MAGIC {
189		return None;
190	}
191	let version = u32::from_le_bytes(bytes[OFF_FORMAT..OFF_MTIME].try_into().ok()?);
192	if version != CACHE_FORMAT_VERSION {
193		return None;
194	}
195	let mtime = u64::from_le_bytes(bytes[OFF_MTIME..OFF_SIZE].try_into().ok()?);
196	let size = u64::from_le_bytes(bytes[OFF_SIZE..OFF_ANCHOR].try_into().ok()?);
197	let anchor_hash = u64::from_le_bytes(bytes[OFF_ANCHOR..OFF_CONTEXT].try_into().ok()?);
198	let context_hash = u64::from_le_bytes(bytes[OFF_CONTEXT..OFF_PATH_LEN].try_into().ok()?);
199	if mtime != key.mtime
200		|| size != key.size
201		|| anchor_hash != key.anchor_hash
202		|| context_hash != key.context_hash
203	{
204		return None;
205	}
206	let path_len = u32::from_le_bytes(bytes[OFF_PATH_LEN..HEADER_FIXED].try_into().ok()?) as usize;
207	if HEADER_FIXED + path_len > bytes.len() {
208		return None;
209	}
210	let stored_path = &bytes[HEADER_FIXED..HEADER_FIXED + path_len];
211	if stored_path != key.abs_path_bytes() {
212		return None;
213	}
214	Some(&bytes[HEADER_FIXED + path_len..])
215}
216
217#[cfg(unix)]
218fn path_bytes(p: &Path) -> &[u8] {
219	use std::os::unix::ffi::OsStrExt;
220	p.as_os_str().as_bytes()
221}
222
223#[cfg(not(unix))]
224fn path_bytes(p: &Path) -> &[u8] {
225	p.to_str().map(|s| s.as_bytes()).unwrap_or(&[])
226}
227
228fn hash_path(p: &Path) -> u64 {
229	let mut h = FxHasher::default();
230	path_bytes(p).hash(&mut h);
231	h.finish()
232}
233
234fn hash_context(ctx: &extract::Context) -> u64 {
235	let mut h = FxHasher::default();
236	ctx.project.hash(&mut h);
237	ctx.ts.aliases.len().hash(&mut h);
238	for alias in &ctx.ts.aliases {
239		alias.pattern.hash(&mut h);
240		alias.substitution.hash(&mut h);
241	}
242	h.finish()
243}
244
245#[cfg(test)]
246mod tests {
247	use super::*;
248	use code_moniker_core::core::moniker::MonikerBuilder;
249
250	fn graph_with_one_def() -> CodeGraph {
251		let root = MonikerBuilder::new()
252			.project(b"app")
253			.segment(b"path", b"root")
254			.build();
255		let mut g = CodeGraph::new(root.clone(), b"module");
256		let child = MonikerBuilder::new()
257			.project(b"app")
258			.segment(b"path", b"root")
259			.segment(b"class", b"Foo")
260			.build();
261		g.add_def(child, b"class", &root, Some((0, 10))).unwrap();
262		g
263	}
264
265	#[test]
266	fn store_then_load_roundtrips() {
267		let tmp = tempfile::tempdir().unwrap();
268		let src = tmp.path().join("src.ts");
269		std::fs::write(&src, b"export class Foo {}\n").unwrap();
270		let anchor = tmp.path().join("anchor");
271		let key = CacheKey::from_path(&src, &anchor).unwrap();
272		let g = graph_with_one_def();
273
274		store(tmp.path(), &key, &g);
275		let back = load(tmp.path(), &key).expect("should hit");
276		assert_eq!(back.def_count(), g.def_count());
277	}
278
279	#[test]
280	fn load_misses_when_mtime_changes() {
281		let tmp = tempfile::tempdir().unwrap();
282		let src = tmp.path().join("src.ts");
283		std::fs::write(&src, b"a").unwrap();
284		let anchor = tmp.path().join("anchor");
285		let key = CacheKey::from_path(&src, &anchor).unwrap();
286		store(tmp.path(), &key, &graph_with_one_def());
287
288		std::thread::sleep(std::time::Duration::from_millis(10));
289		std::fs::write(&src, b"ab").unwrap();
290		let key2 = CacheKey::from_path(&src, &anchor).unwrap();
291		assert!(key2.mtime != key.mtime || key2.size != key.size);
292		assert!(load(tmp.path(), &key2).is_none());
293	}
294
295	#[test]
296	fn load_misses_when_anchor_changes() {
297		let tmp = tempfile::tempdir().unwrap();
298		let src = tmp.path().join("src.ts");
299		std::fs::write(&src, b"a").unwrap();
300		let anchor1 = tmp.path().join("anchor1");
301		let anchor2 = tmp.path().join("anchor2");
302		let key1 = CacheKey::from_path(&src, &anchor1).unwrap();
303		let key2 = CacheKey::from_path(&src, &anchor2).unwrap();
304		store(tmp.path(), &key1, &graph_with_one_def());
305		assert!(load(tmp.path(), &key1).is_some());
306		assert!(load(tmp.path(), &key2).is_none());
307	}
308
309	#[test]
310	fn load_misses_when_context_changes() {
311		let tmp = tempfile::tempdir().unwrap();
312		let src = tmp.path().join("src.ts");
313		std::fs::write(&src, b"export class Foo {}\n").unwrap();
314		let anchor = tmp.path().join("anchor");
315		let ctx_one = extract::Context {
316			project: Some("one".into()),
317			..extract::Context::default()
318		};
319		let ctx_two = extract::Context {
320			project: Some("two".into()),
321			..extract::Context::default()
322		};
323		let key1 = CacheKey::from_path_with_context(&src, &anchor, &ctx_one).unwrap();
324		let key2 = CacheKey::from_path_with_context(&src, &anchor, &ctx_two).unwrap();
325
326		store(tmp.path(), &key1, &graph_with_one_def());
327
328		assert!(load(tmp.path(), &key1).is_some());
329		assert!(load(tmp.path(), &key2).is_none());
330		assert_ne!(key1.full_path(tmp.path()), key2.full_path(tmp.path()));
331	}
332
333	#[test]
334	fn load_returns_none_on_empty_dir() {
335		let tmp = tempfile::tempdir().unwrap();
336		let src = tmp.path().join("src.ts");
337		std::fs::write(&src, b"a").unwrap();
338		let key = CacheKey::from_path(&src, tmp.path()).unwrap();
339		assert!(load(tmp.path(), &key).is_none());
340	}
341
342	#[test]
343	fn cache_path_is_versioned_and_sharded() {
344		let tmp = tempfile::tempdir().unwrap();
345		let src = tmp.path().join("src.ts");
346		std::fs::write(&src, b"a").unwrap();
347		let key = CacheKey::from_path(&src, tmp.path()).unwrap();
348		let full = key.full_path(tmp.path());
349		let s = full.to_string_lossy();
350		assert!(s.contains(&format!("v{LAYOUT_VERSION}_{CACHE_FORMAT_VERSION}")));
351		assert!(full.parent().unwrap().file_name().unwrap().len() == 2);
352	}
353}