crates/oxy-core/src/repo/config.rs at b63fc7a77fc6 · andymccall/oxygen

# b63fc7a77fc6 oxygen / crates / oxy-core / src / repo / config.rs

14.6 KiB · Rust · last changed Agents sign keyless: author.signer = keyless (keyless step 5c) 18 days ago source blame history raw

//! Layered configuration: defaults, the user file, the repository file.

use super::*;

/// Effective settings: defaults, then the user file (`~/.config/oxy/config.toml`,
/// spec §19), then the repository file (`.oxy/config`). Both files are
/// `key = "value"` lines. `save` writes only the repository layer.
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct Config {
    /// Keys set in the repository file (or via `set`), written by `save`.
    repo_layer: BTreeMap<String, String>,
    pub author_name: String,
    pub author_email: String,
    /// The KeyId of the author's identity, once `create_identity` has run.
    pub author_key: Option<KeyId>,
    /// `author.signer` (or `$OXY_SIGNER`): the key that signs and seals in
    /// place of `author.key`, whose identity lists it as a delegate. An
    /// agent sets it to its own key, so its changes carry the human as
    /// author and the agent's signature (spec §14.2, agent workflows §2).
    pub signer_key: Option<KeyId>,
    /// `author.signer = "keyless"`: sign with fresh keys the hub certifies
    /// under the agent's grant, keeping no key on disk (spec §14.7,
    /// oxygenhub#241).
    pub signer_keyless: bool,
    /// `keyless.hub`: the hub that certifies them (default: the default
    /// remote's hub).
    pub keyless_hub: Option<String>,
    /// `core.sign`: sign every change at commit (`true`) or leave signing to
    /// push-time seals (`false`, the spec default).
    pub sign_changes: bool,
    pub bookmark: String,
    /// `remote.<name>.url`.
    pub remotes: BTreeMap<String, String>,
    /// `remote.<name>.token`: bearer token for HTTP pushes.
    pub remote_tokens: BTreeMap<String, String>,
    /// `remote.<name>.ca`: PEM file of extra roots to trust for that remote.
    pub remote_cas: BTreeMap<String, String>,
    /// `core.remote`: the remote `pull`, `fetch` and `push` use when none is
    /// named, for a repository whose remotes include no `origin`.
    pub default_remote: Option<String>,
    /// `git.claim`: a Git import authors the commits whose Git author email
    /// is this repository's identity's with its key (oxygen#97).
    pub git_claim: bool,
    /// `core.op-retention`: days for which operations keep their states reachable (spec §12.1, §21).
    pub op_retention_days: u64,
    /// `core.gc-grace`: days an unreachable object survives, protecting concurrent writers (spec §21).
    pub gc_grace_days: u64,
    /// `core.snapshot-retention`: days for which past operations keep their
    /// working copies reachable (oxygen#98); each workspace's current one is
    /// always kept. A file only ever in a working copy goes with it.
    pub snapshot_retention_days: u64,
    /// `snapshot.max-new-file-size`: a new, untracked file larger than this
    /// is left out of working-copy snapshots and named instead (oxygen#98);
    /// 0 takes in files of any size.
    pub max_new_file: u64,
    /// `core.checkpoint-interval`: changes between automatic checkpoints (spec §11).
    pub checkpoint_interval: u64,
    /// `push.batch-bytes`: about how many bytes of changes and their texts
    /// one request of a long push carries (spec §16.3).
    pub push_batch_bytes: u64,
    /// `filter.max-blob`: blobs larger than this many bytes are fetched lazily (spec §17).
    pub max_blob: Option<u64>,
    /// `filter.paths`: only these subtrees are materialized (spec §17); empty means everything.
    pub sparse_paths: Vec<String>,
    /// `hooks.semantic-deps`: run the semantic-deps hook at commit (spec §20).
    pub semantic_deps: bool,
    /// `revset.<name>`: a saved revset, used as `name()`.
    pub revsets: BTreeMap<String, String>,
    /// `storage.url`: the store the repository's objects and operation
    /// head are kept on (`dir://`, `s3://`, …) instead of `.oxy/objects`
    /// (oxygen#68).
    pub storage_url: Option<String>,
    /// `storage.cache`: the most the local cache in front of that store
    /// holds, in bytes.
    pub storage_cache: u64,
}

impl Config {
    /// Whether the repository's own file sets `key` (as against the user
    /// config or a default).
    pub fn is_repo_set(&self, key: &str) -> bool {
        self.repo_layer.contains_key(key)
    }

    pub(super) fn default_for_user() -> Config {
        let user = std::env::var("USER").unwrap_or_else(|_| "unknown".into());
        Config {
            repo_layer: BTreeMap::new(),
            author_name: std::env::var("OXY_AUTHOR_NAME").unwrap_or_else(|_| user.clone()),
            author_email: std::env::var("OXY_AUTHOR_EMAIL")
                .unwrap_or_else(|_| format!("{user}@localhost")),
            author_key: None,
            signer_key: std::env::var("OXY_SIGNER")
                .ok()
                .and_then(|v| KeyId::from_hex(&v)),
            signer_keyless: std::env::var("OXY_SIGNER").is_ok_and(|v| v == "keyless"),
            keyless_hub: None,
            sign_changes: false,
            bookmark: "main".into(),
            remotes: BTreeMap::new(),
            remote_tokens: BTreeMap::new(),
            remote_cas: BTreeMap::new(),
            default_remote: None,
            git_claim: false,
            op_retention_days: 90,
            gc_grace_days: 14,
            max_new_file: 100 << 20,
            snapshot_retention_days: 7,
            checkpoint_interval: 256,
            push_batch_bytes: 256 << 20,
            max_blob: None,
            sparse_paths: Vec::new(),
            semantic_deps: false,
            revsets: BTreeMap::new(),
            storage_url: None,
            storage_cache: DEFAULT_STORAGE_CACHE,
        }
    }

    /// Set a key in the repository layer, as `oxy config` does.
    pub fn set(&mut self, key: &str, value: &str) -> Result<()> {
        self.apply(key, value)?;
        if value.is_empty() {
            self.repo_layer.remove(key);
        } else {
            self.repo_layer.insert(key.to_string(), value.to_string());
        }
        Ok(())
    }

    /// Set a key in the user file without touching any repository.
    pub fn set_user(user_path: &Path, key: &str, value: &str) -> Result<()> {
        Config::default_for_user().apply(key, value)?;
        let mut entries = read_config_file(user_path)?;
        if value.is_empty() {
            entries.remove(key);
        } else {
            entries.insert(key.to_string(), value.to_string());
        }
        if let Some(parent) = user_path.parent() {
            fs::create_dir_all(parent)?;
        }
        write_config_file(user_path, &entries)
    }

    /// Apply a key to the effective values.
    pub(super) fn apply(&mut self, key: &str, value: &str) -> Result<()> {
        match key {
            "author.name" => self.author_name = value.into(),
            "author.email" => self.author_email = value.into(),
            "author.key" => {
                self.author_key = if value.is_empty() {
                    None
                } else {
                    Some(KeyId::from_hex(value).ok_or_else(|| {
                        RepoError::Msg("author.key must be a 64-character hex KeyId".into())
                    })?)
                }
            }
            "author.signer" => {
                self.signer_keyless = value == "keyless";
                self.signer_key = if value.is_empty() || self.signer_keyless {
                    None
                } else {
                    Some(KeyId::from_hex(value).ok_or_else(|| {
                        RepoError::Msg(
                            "author.signer must be a 64-character hex KeyId, or \"keyless\"".into(),
                        )
                    })?)
                }
            }
            "core.sign" => {
                self.sign_changes = match value {
                    "change" => true,
                    "seal" => false,
                    _ => return fail("core.sign must be \"change\" or \"seal\""),
                }
            }
            "workspace.bookmark" => self.bookmark = value.into(),
            "keyless.hub" => self.keyless_hub = (!value.is_empty()).then(|| value.to_string()),
            // Read by the credential store from the user file.
            "auth.helper" => {}
            "core.op-retention" => self.op_retention_days = parse_days(value)?,
            "core.gc-grace" => self.gc_grace_days = parse_days(value)?,
            "snapshot.max-new-file-size" => self.max_new_file = parse_size(value)?,
            "core.snapshot-retention" => self.snapshot_retention_days = parse_days(value)?,
            "filter.max-blob" => {
                self.max_blob = if value.is_empty() {
                    None
                } else {
                    Some(parse_size(value)?)
                }
            }
            "storage.url" => {
                self.storage_url = (!value.is_empty()).then(|| value.to_string());
            }
            "storage.cache" => {
                self.storage_cache = if value.is_empty() {
                    DEFAULT_STORAGE_CACHE
                } else {
                    parse_size(value)?
                }
            }
            "core.remote" => {
                self.default_remote = (!value.is_empty()).then(|| value.to_string());
            }
            "hooks.semantic-deps" => self.semantic_deps = matches!(value, "true" | "1" | "yes"),
            "git.claim" => self.git_claim = matches!(value, "true" | "1" | "yes"),
            "filter.paths" => {
                self.sparse_paths = value
                    .split(',')
                    .map(|p| {
                        p.trim()
                            .trim_start_matches("./")
                            .trim_matches('/')
                            .to_string()
                    })
                    .filter(|p| !p.is_empty())
                    .collect();
            }
            "core.checkpoint-interval" => {
                self.checkpoint_interval = value
                    .parse()
                    .map_err(|_| RepoError::Msg(format!("expected a number, got {value:?}")))?;
            }
            "push.batch-bytes" => {
                self.push_batch_bytes = value.parse().ok().filter(|n| *n > 0).ok_or_else(|| {
                    RepoError::Msg(format!("expected a number of bytes, got {value:?}"))
                })?;
            }
            k if k.starts_with("remote.") => {
                let rest = &k["remote.".len()..];
                let Some((name, field)) = rest.rsplit_once('.') else {
                    return fail(format!("unknown configuration key {key:?}"));
                };
                if name.is_empty() || name.contains('/') {
                    return fail(format!("invalid remote name in {key:?}"));
                }
                let map = match field {
                    "url" => &mut self.remotes,
                    "token" => &mut self.remote_tokens,
                    "ca" => &mut self.remote_cas,
                    _ => return fail(format!("unknown configuration key {key:?}")),
                };
                if value.is_empty() {
                    map.remove(name);
                    if field == "url" {
                        self.remote_tokens.remove(name);
                        self.remote_cas.remove(name);
                    }
                } else {
                    map.insert(name.to_string(), value.into());
                }
            }
            k if k.starts_with("revset.") => {
                let name = &k["revset.".len()..];
                if name.is_empty()
                    || !name
                        .chars()
                        .all(|c| c.is_ascii_alphanumeric() || c == '_' || c == '-')
                {
                    return fail(format!(
                        "a revset's name is letters, digits, _ and -: {key:?}"
                    ));
                }
                if value.is_empty() {
                    self.revsets.remove(name);
                } else {
                    crate::revset::parse(value)
                        .map_err(|e| RepoError::Msg(format!("{key} = {value:?}: {e}")))?;
                    self.revsets.insert(name.to_string(), value.into());
                }
            }
            _ => return fail(format!("unknown configuration key {key:?}")),
        }
        Ok(())
    }

    /// Defaults, then the user file if it exists, then the repository file.
    pub(super) fn load(user_path: Option<&Path>, repo_path: &Path) -> Result<Config> {
        let mut c = Config::default_for_user();
        if let Some(u) = user_path {
            for (k, v) in read_config_file(u)? {
                let _ = c.apply(&k, &v);
            }
        }
        for (k, v) in read_config_file(repo_path)? {
            if c.apply(&k, &v).is_ok() {
                c.repo_layer.insert(k, v);
            }
        }
        Ok(c)
    }

    pub(super) fn save(&self, path: &Path) -> Result<()> {
        write_config_file(path, &self.repo_layer)
    }

    /// Keys explicitly set for this repository.
    pub fn repo_layer(&self) -> &BTreeMap<String, String> {
        &self.repo_layer
    }
}

/// A byte count with an optional `K`, `M`, or `G` suffix (binary units).
/// `storage.cache` when unset: 2 GiB.
pub const DEFAULT_STORAGE_CACHE: u64 = 2 << 30;

pub fn parse_size(v: &str) -> Result<u64> {
    let v = v.trim();
    let (num, mult) = match v.chars().last() {
        Some('K' | 'k') => (&v[..v.len() - 1], 1u64 << 10),
        Some('M' | 'm') => (&v[..v.len() - 1], 1u64 << 20),
        Some('G' | 'g') => (&v[..v.len() - 1], 1u64 << 30),
        _ => (v, 1),
    };
    let n: u64 = num
        .trim()
        .parse()
        .map_err(|_| RepoError::Msg(format!("expected a size like 1M, got {v:?}")))?;
    Ok(n * mult)
}

/// A count of days, optionally suffixed `d`.
fn parse_days(v: &str) -> Result<u64> {
    v.trim_end_matches('d')
        .parse()
        .map_err(|_| RepoError::Msg(format!("expected a number of days, got {v:?}")))
}

/// Read `key = "value"` lines; a missing file is empty.
pub fn read_config_file(path: &Path) -> Result<BTreeMap<String, String>> {
    let text = match fs::read_to_string(path) {
        Ok(t) => t,
        Err(e) if e.kind() == std::io::ErrorKind::NotFound => return Ok(BTreeMap::new()),
        Err(e) => return Err(e.into()),
    };
    let mut out = BTreeMap::new();
    for line in text.lines() {
        let line = line.trim();
        if line.is_empty() || line.starts_with('#') {
            continue;
        }
        let Some((k, v)) = line.split_once('=') else {
            continue;
        };
        out.insert(k.trim().to_string(), v.trim().trim_matches('"').to_string());
    }
    Ok(out)
}

fn write_config_file(path: &Path, entries: &BTreeMap<String, String>) -> Result<()> {
    let text: String = entries
        .iter()
        .map(|(k, v)| format!("{k} = \"{v}\"\n"))
        .collect();
    write_atomic(path, text.as_bytes())
}

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1	//! Layered configuration: defaults, the user file, the repository file.
2
3	use super::*;
4
5	/// Effective settings: defaults, then the user file (`~/.config/oxy/config.toml`,
6	/// spec §19), then the repository file (`.oxy/config`). Both files are
7	/// `key = "value"` lines. `save` writes only the repository layer.
8	#[derive(Clone, Debug, PartialEq, Eq)]
9	pub struct Config {
10	/// Keys set in the repository file (or via `set`), written by `save`.
11	repo_layer: BTreeMap<String, String>,
12	pub author_name: String,
13	pub author_email: String,
14	/// The KeyId of the author's identity, once `create_identity` has run.
15	pub author_key: Option<KeyId>,
16	/// `author.signer` (or `$OXY_SIGNER`): the key that signs and seals in
17	/// place of `author.key`, whose identity lists it as a delegate. An
18	/// agent sets it to its own key, so its changes carry the human as
19	/// author and the agent's signature (spec §14.2, agent workflows §2).
20	pub signer_key: Option<KeyId>,
21	/// `author.signer = "keyless"`: sign with fresh keys the hub certifies
22	/// under the agent's grant, keeping no key on disk (spec §14.7,
23	/// oxygenhub#241).
24	pub signer_keyless: bool,
25	/// `keyless.hub`: the hub that certifies them (default: the default
26	/// remote's hub).
27	pub keyless_hub: Option<String>,
28	/// `core.sign`: sign every change at commit (`true`) or leave signing to
29	/// push-time seals (`false`, the spec default).
30	pub sign_changes: bool,
31	pub bookmark: String,
32	/// `remote.<name>.url`.
33	pub remotes: BTreeMap<String, String>,
34	/// `remote.<name>.token`: bearer token for HTTP pushes.
35	pub remote_tokens: BTreeMap<String, String>,
36	/// `remote.<name>.ca`: PEM file of extra roots to trust for that remote.
37	pub remote_cas: BTreeMap<String, String>,
38	/// `core.remote`: the remote `pull`, `fetch` and `push` use when none is
39	/// named, for a repository whose remotes include no `origin`.
40	pub default_remote: Option<String>,
41	/// `git.claim`: a Git import authors the commits whose Git author email
42	/// is this repository's identity's with its key (oxygen#97).
43	pub git_claim: bool,
44	/// `core.op-retention`: days for which operations keep their states reachable (spec §12.1, §21).
45	pub op_retention_days: u64,
46	/// `core.gc-grace`: days an unreachable object survives, protecting concurrent writers (spec §21).
47	pub gc_grace_days: u64,
48	/// `core.snapshot-retention`: days for which past operations keep their
49	/// working copies reachable (oxygen#98); each workspace's current one is
50	/// always kept. A file only ever in a working copy goes with it.
51	pub snapshot_retention_days: u64,
52	/// `snapshot.max-new-file-size`: a new, untracked file larger than this
53	/// is left out of working-copy snapshots and named instead (oxygen#98);
54	/// 0 takes in files of any size.
55	pub max_new_file: u64,
56	/// `core.checkpoint-interval`: changes between automatic checkpoints (spec §11).
57	pub checkpoint_interval: u64,
58	/// `push.batch-bytes`: about how many bytes of changes and their texts
59	/// one request of a long push carries (spec §16.3).
60	pub push_batch_bytes: u64,
61	/// `filter.max-blob`: blobs larger than this many bytes are fetched lazily (spec §17).
62	pub max_blob: Option<u64>,
63	/// `filter.paths`: only these subtrees are materialized (spec §17); empty means everything.
64	pub sparse_paths: Vec<String>,
65	/// `hooks.semantic-deps`: run the semantic-deps hook at commit (spec §20).
66	pub semantic_deps: bool,
67	/// `revset.<name>`: a saved revset, used as `name()`.
68	pub revsets: BTreeMap<String, String>,
69	/// `storage.url`: the store the repository's objects and operation
70	/// head are kept on (`dir://`, `s3://`, …) instead of `.oxy/objects`
71	/// (oxygen#68).
72	pub storage_url: Option<String>,
73	/// `storage.cache`: the most the local cache in front of that store
74	/// holds, in bytes.
75	pub storage_cache: u64,
76	}
77
78	impl Config {
79	/// Whether the repository's own file sets `key` (as against the user
80	/// config or a default).
81	pub fn is_repo_set(&self, key: &str) -> bool {
82	self.repo_layer.contains_key(key)
83	}
84
85	pub(super) fn default_for_user() -> Config {
86	let user = std::env::var("USER").unwrap_or_else(\|_\| "unknown".into());
87	Config {
88	repo_layer: BTreeMap::new(),
89	author_name: std::env::var("OXY_AUTHOR_NAME").unwrap_or_else(\|_\| user.clone()),
90	author_email: std::env::var("OXY_AUTHOR_EMAIL")
91	.unwrap_or_else(\|_\| format!("{user}@localhost")),
92	author_key: None,
93	signer_key: std::env::var("OXY_SIGNER")
94	.ok()
95	.and_then(\|v\| KeyId::from_hex(&v)),
96	signer_keyless: std::env::var("OXY_SIGNER").is_ok_and(\|v\| v == "keyless"),
97	keyless_hub: None,
98	sign_changes: false,
99	bookmark: "main".into(),
100	remotes: BTreeMap::new(),
101	remote_tokens: BTreeMap::new(),
102	remote_cas: BTreeMap::new(),
103	default_remote: None,
104	git_claim: false,
105	op_retention_days: 90,
106	gc_grace_days: 14,
107	max_new_file: 100 << 20,
108	snapshot_retention_days: 7,
109	checkpoint_interval: 256,
110	push_batch_bytes: 256 << 20,
111	max_blob: None,
112	sparse_paths: Vec::new(),
113	semantic_deps: false,
114	revsets: BTreeMap::new(),
115	storage_url: None,
116	storage_cache: DEFAULT_STORAGE_CACHE,
117	}
118	}
119
120	/// Set a key in the repository layer, as `oxy config` does.
121	pub fn set(&mut self, key: &str, value: &str) -> Result<()> {
122	self.apply(key, value)?;
123	if value.is_empty() {
124	self.repo_layer.remove(key);
125	} else {
126	self.repo_layer.insert(key.to_string(), value.to_string());
127	}
128	Ok(())
129	}
130
131	/// Set a key in the user file without touching any repository.
132	pub fn set_user(user_path: &Path, key: &str, value: &str) -> Result<()> {
133	Config::default_for_user().apply(key, value)?;
134	let mut entries = read_config_file(user_path)?;
135	if value.is_empty() {
136	entries.remove(key);
137	} else {
138	entries.insert(key.to_string(), value.to_string());
139	}
140	if let Some(parent) = user_path.parent() {
141	fs::create_dir_all(parent)?;
142	}
143	write_config_file(user_path, &entries)
144	}
145
146	/// Apply a key to the effective values.
147	pub(super) fn apply(&mut self, key: &str, value: &str) -> Result<()> {
148	match key {
149	"author.name" => self.author_name = value.into(),
150	"author.email" => self.author_email = value.into(),
151	"author.key" => {
152	self.author_key = if value.is_empty() {
153	None
154	} else {
155	Some(KeyId::from_hex(value).ok_or_else(\|\| {
156	RepoError::Msg("author.key must be a 64-character hex KeyId".into())
157	})?)
158	}
159	}
160	"author.signer" => {
161	self.signer_keyless = value == "keyless";
162	self.signer_key = if value.is_empty() \|\| self.signer_keyless {
163	None
164	} else {
165	Some(KeyId::from_hex(value).ok_or_else(\|\| {
166	RepoError::Msg(
167	"author.signer must be a 64-character hex KeyId, or \"keyless\"".into(),
168	)
169	})?)
170	}
171	}
172	"core.sign" => {
173	self.sign_changes = match value {
174	"change" => true,
175	"seal" => false,
176	_ => return fail("core.sign must be \"change\" or \"seal\""),
177	}
178	}
179	"workspace.bookmark" => self.bookmark = value.into(),
180	"keyless.hub" => self.keyless_hub = (!value.is_empty()).then(\|\| value.to_string()),
181	// Read by the credential store from the user file.
182	"auth.helper" => {}
183	"core.op-retention" => self.op_retention_days = parse_days(value)?,
184	"core.gc-grace" => self.gc_grace_days = parse_days(value)?,
185	"snapshot.max-new-file-size" => self.max_new_file = parse_size(value)?,
186	"core.snapshot-retention" => self.snapshot_retention_days = parse_days(value)?,
187	"filter.max-blob" => {
188	self.max_blob = if value.is_empty() {
189	None
190	} else {
191	Some(parse_size(value)?)
192	}
193	}
194	"storage.url" => {
195	self.storage_url = (!value.is_empty()).then(\|\| value.to_string());
196	}
197	"storage.cache" => {
198	self.storage_cache = if value.is_empty() {
199	DEFAULT_STORAGE_CACHE
200	} else {
201	parse_size(value)?
202	}
203	}
204	"core.remote" => {
205	self.default_remote = (!value.is_empty()).then(\|\| value.to_string());
206	}
207	"hooks.semantic-deps" => self.semantic_deps = matches!(value, "true" \| "1" \| "yes"),
208	"git.claim" => self.git_claim = matches!(value, "true" \| "1" \| "yes"),
209	"filter.paths" => {
210	self.sparse_paths = value
211	.split(',')
212	.map(\|p\| {
213	p.trim()
214	.trim_start_matches("./")
215	.trim_matches('/')
216	.to_string()
217	})
218	.filter(\|p\| !p.is_empty())
219	.collect();
220	}
221	"core.checkpoint-interval" => {
222	self.checkpoint_interval = value
223	.parse()
224	.map_err(\|_\| RepoError::Msg(format!("expected a number, got {value:?}")))?;
225	}
226	"push.batch-bytes" => {
227	self.push_batch_bytes = value.parse().ok().filter(\|n\| *n > 0).ok_or_else(\|\| {
228	RepoError::Msg(format!("expected a number of bytes, got {value:?}"))
229	})?;
230	}
231	k if k.starts_with("remote.") => {
232	let rest = &k["remote.".len()..];
233	let Some((name, field)) = rest.rsplit_once('.') else {
234	return fail(format!("unknown configuration key {key:?}"));
235	};
236	if name.is_empty() \|\| name.contains('/') {
237	return fail(format!("invalid remote name in {key:?}"));
238	}
239	let map = match field {
240	"url" => &mut self.remotes,
241	"token" => &mut self.remote_tokens,
242	"ca" => &mut self.remote_cas,
243	_ => return fail(format!("unknown configuration key {key:?}")),
244	};
245	if value.is_empty() {
246	map.remove(name);
247	if field == "url" {
248	self.remote_tokens.remove(name);
249	self.remote_cas.remove(name);
250	}
251	} else {
252	map.insert(name.to_string(), value.into());
253	}
254	}
255	k if k.starts_with("revset.") => {
256	let name = &k["revset.".len()..];
257	if name.is_empty()
258	\|\| !name
259	.chars()
260	.all(\|c\| c.is_ascii_alphanumeric() \|\| c == '_' \|\| c == '-')
261	{
262	return fail(format!(
263	"a revset's name is letters, digits, _ and -: {key:?}"
264	));
265	}
266	if value.is_empty() {
267	self.revsets.remove(name);
268	} else {
269	crate::revset::parse(value)
270	.map_err(\|e\| RepoError::Msg(format!("{key} = {value:?}: {e}")))?;
271	self.revsets.insert(name.to_string(), value.into());
272	}
273	}
274	_ => return fail(format!("unknown configuration key {key:?}")),
275	}
276	Ok(())
277	}
278
279	/// Defaults, then the user file if it exists, then the repository file.
280	pub(super) fn load(user_path: Option<&Path>, repo_path: &Path) -> Result<Config> {
281	let mut c = Config::default_for_user();
282	if let Some(u) = user_path {
283	for (k, v) in read_config_file(u)? {
284	let _ = c.apply(&k, &v);
285	}
286	}
287	for (k, v) in read_config_file(repo_path)? {
288	if c.apply(&k, &v).is_ok() {
289	c.repo_layer.insert(k, v);
290	}
291	}
292	Ok(c)
293	}
294
295	pub(super) fn save(&self, path: &Path) -> Result<()> {
296	write_config_file(path, &self.repo_layer)
297	}
298
299	/// Keys explicitly set for this repository.
300	pub fn repo_layer(&self) -> &BTreeMap<String, String> {
301	&self.repo_layer
302	}
303	}
304
305	/// A byte count with an optional `K`, `M`, or `G` suffix (binary units).
306	/// `storage.cache` when unset: 2 GiB.
307	pub const DEFAULT_STORAGE_CACHE: u64 = 2 << 30;
308
309	pub fn parse_size(v: &str) -> Result<u64> {
310	let v = v.trim();
311	let (num, mult) = match v.chars().last() {
312	Some('K' \| 'k') => (&v[..v.len() - 1], 1u64 << 10),
313	Some('M' \| 'm') => (&v[..v.len() - 1], 1u64 << 20),
314	Some('G' \| 'g') => (&v[..v.len() - 1], 1u64 << 30),
315	_ => (v, 1),
316	};
317	let n: u64 = num
318	.trim()
319	.parse()
320	.map_err(\|_\| RepoError::Msg(format!("expected a size like 1M, got {v:?}")))?;
321	Ok(n * mult)
322	}
323
324	/// A count of days, optionally suffixed `d`.
325	fn parse_days(v: &str) -> Result<u64> {
326	v.trim_end_matches('d')
327	.parse()
328	.map_err(\|_\| RepoError::Msg(format!("expected a number of days, got {v:?}")))
329	}
330
331	/// Read `key = "value"` lines; a missing file is empty.
332	pub fn read_config_file(path: &Path) -> Result<BTreeMap<String, String>> {
333	let text = match fs::read_to_string(path) {
334	Ok(t) => t,
335	Err(e) if e.kind() == std::io::ErrorKind::NotFound => return Ok(BTreeMap::new()),
336	Err(e) => return Err(e.into()),
337	};
338	let mut out = BTreeMap::new();
339	for line in text.lines() {
340	let line = line.trim();
341	if line.is_empty() \|\| line.starts_with('#') {
342	continue;
343	}
344	let Some((k, v)) = line.split_once('=') else {
345	continue;
346	};
347	out.insert(k.trim().to_string(), v.trim().trim_matches('"').to_string());
348	}
349	Ok(out)
350	}
351
352	fn write_config_file(path: &Path, entries: &BTreeMap<String, String>) -> Result<()> {
353	let text: String = entries
354	.iter()
355	.map(\|(k, v)\| format!("{k} = \"{v}\"\n"))
356	.collect();
357	write_atomic(path, text.as_bytes())
358	}

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