diff options
Diffstat (limited to 'tvix/store/src/store_path.rs')
| -rw-r--r-- | tvix/store/src/store_path.rs | 198 |
1 files changed, 0 insertions, 198 deletions
diff --git a/tvix/store/src/store_path.rs b/tvix/store/src/store_path.rs deleted file mode 100644 index 5032a73fb19b..000000000000 --- a/tvix/store/src/store_path.rs +++ /dev/null @@ -1,198 +0,0 @@ -use crate::nixbase32::{self, Nixbase32DecodeError}; -use std::fmt; -use thiserror::Error; - -pub const DIGEST_SIZE: usize = 20; -// lazy_static doesn't allow us to call NIXBASE32.encode_len(), so we ran it -// manually and have an assert in the tests. -pub const ENCODED_DIGEST_SIZE: usize = 32; - -// The store dir prefix, without trailing slash. -// That's usually where the Nix store is mounted at. -pub const STORE_DIR: &str = "/nix/store"; -pub const STORE_DIR_WITH_SLASH: &str = "/nix/store/"; - -/// Errors that can occur during the validation of name characters. -#[derive(Debug, PartialEq, Eq, Error)] -pub enum ParseStorePathError { - #[error("Dash is missing between hash and name")] - MissingDash(), - #[error("Hash encoding is invalid: {0}")] - InvalidHashEncoding(Nixbase32DecodeError), - #[error("Invalid name: {0}")] - InvalidName(String), - #[error("Tried to parse an absolute path which was missing the store dir prefix.")] - MissingStoreDir(), -} - -/// Represents a path in the Nix store (a direct child of [STORE_DIR]). -/// -/// It starts with a digest (20 bytes), [struct@NIXBASE32]-encoded, followed by -/// a `-`, and ends with a `name`, which is a string, consisting only of ASCCI -/// alphanumeric characters, or one of the following characters: `-`, `_`, `.`, -/// `+`, `?`, `=`. -/// -/// The name is usually used to describe the pname and version of a package. -/// Derivations paths can also be represented as store paths, they end -/// with .drv. -#[derive(Clone, Debug, PartialEq, Eq)] -pub struct StorePath { - pub digest: [u8; DIGEST_SIZE], - pub name: String, -} - -impl StorePath { - pub fn from_string(s: &str) -> Result<StorePath, ParseStorePathError> { - // the whole string needs to be at least: - // - // - 32 characters (encoded hash) - // - 1 dash - // - 1 character for the name - if s.len() < ENCODED_DIGEST_SIZE + 2 { - return Err(ParseStorePathError::InvalidName("".to_string())); - } - - let digest = match nixbase32::decode(s[..ENCODED_DIGEST_SIZE].as_bytes()) { - Ok(decoded) => decoded, - Err(decoder_error) => { - return Err(ParseStorePathError::InvalidHashEncoding(decoder_error)) - } - }; - - if s.as_bytes()[ENCODED_DIGEST_SIZE] != b'-' { - return Err(ParseStorePathError::MissingDash()); - } - - StorePath::validate_name(&s[ENCODED_DIGEST_SIZE + 2..])?; - - Ok(StorePath { - name: s[ENCODED_DIGEST_SIZE + 1..].to_string(), - digest: digest.try_into().expect("size is known"), - }) - } - - /// Construct a [StorePath] from an absolute store path string. - /// That is a string starting with the store prefix (/nix/store) - pub fn from_absolute_path(s: &str) -> Result<StorePath, ParseStorePathError> { - match s.strip_prefix(STORE_DIR_WITH_SLASH) { - Some(s_stripped) => Self::from_string(s_stripped), - None => Err(ParseStorePathError::MissingStoreDir()), - } - } - - /// Converts the [StorePath] to an absolute store path string. - /// That is a string starting with the store prefix (/nix/store) - pub fn to_absolute_path(&self) -> String { - format!("{}/{}", STORE_DIR, self) - } - - /// Checks a given &str to match the restrictions for store path names. - pub fn validate_name(s: &str) -> Result<(), ParseStorePathError> { - for c in s.chars() { - if c.is_ascii_alphanumeric() - || c == '-' - || c == '_' - || c == '.' - || c == '+' - || c == '?' - || c == '=' - { - continue; - } - - return Err(ParseStorePathError::InvalidName(s.to_string())); - } - - Ok(()) - } -} - -impl fmt::Display for StorePath { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - write!(f, "{}-{}", nixbase32::encode(&self.digest), self.name) - } -} - -#[cfg(test)] -mod tests { - use crate::nixbase32; - use crate::store_path::{DIGEST_SIZE, ENCODED_DIGEST_SIZE}; - - use super::{ParseStorePathError, StorePath}; - - #[test] - fn encoded_digest_size() { - assert_eq!(ENCODED_DIGEST_SIZE, nixbase32::encode_len(DIGEST_SIZE)); - } - - #[test] - fn happy_path() { - let example_nix_path_str = - "00bgd045z0d4icpbc2yyz4gx48ak44la-net-tools-1.60_p20170221182432"; - let nixpath = - StorePath::from_string(&example_nix_path_str).expect("Error parsing example string"); - - let expected_digest: [u8; DIGEST_SIZE] = [ - 0x8a, 0x12, 0x32, 0x15, 0x22, 0xfd, 0x91, 0xef, 0xbd, 0x60, 0xeb, 0xb2, 0x48, 0x1a, - 0xf8, 0x85, 0x80, 0xf6, 0x16, 0x00, - ]; - - assert_eq!("net-tools-1.60_p20170221182432", nixpath.name); - assert_eq!(nixpath.digest, expected_digest); - - assert_eq!(example_nix_path_str, nixpath.to_string()) - } - - #[test] - fn invalid_hash_length() { - StorePath::from_string("00bgd045z0d4icpbc2yy-net-tools-1.60_p20170221182432") - .expect_err("No error raised."); - } - - #[test] - fn invalid_encoding_hash() { - StorePath::from_string("00bgd045z0d4icpbc2yyz4gx48aku4la-net-tools-1.60_p20170221182432") - .expect_err("No error raised."); - } - - #[test] - fn more_than_just_the_bare_nix_store_path() { - StorePath::from_string( - "00bgd045z0d4icpbc2yyz4gx48aku4la-net-tools-1.60_p20170221182432/bin/arp", - ) - .expect_err("No error raised."); - } - - #[test] - fn no_dash_between_hash_and_name() { - StorePath::from_string("00bgd045z0d4icpbc2yyz4gx48ak44lanet-tools-1.60_p20170221182432") - .expect_err("No error raised."); - } - - #[test] - fn absolute_path() { - let example_nix_path_str = - "00bgd045z0d4icpbc2yyz4gx48ak44la-net-tools-1.60_p20170221182432"; - let nixpath_expected = StorePath::from_string(&example_nix_path_str).expect("must parse"); - - let nixpath_actual = StorePath::from_absolute_path( - "/nix/store/00bgd045z0d4icpbc2yyz4gx48ak44la-net-tools-1.60_p20170221182432", - ) - .expect("must parse"); - - assert_eq!(nixpath_expected, nixpath_actual); - - assert_eq!( - "/nix/store/00bgd045z0d4icpbc2yyz4gx48ak44la-net-tools-1.60_p20170221182432", - nixpath_actual.to_absolute_path(), - ); - } - - #[test] - fn absolute_path_missing_prefix() { - assert_eq!( - ParseStorePathError::MissingStoreDir(), - StorePath::from_absolute_path("foobar-123").expect_err("must fail") - ); - } -} |