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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/rust/sync-guid/src
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/sync-guid/src')
-rw-r--r--third_party/rust/sync-guid/src/lib.rs482
-rw-r--r--third_party/rust/sync-guid/src/rusqlite_support.rs23
-rw-r--r--third_party/rust/sync-guid/src/serde_support.rs61
3 files changed, 566 insertions, 0 deletions
diff --git a/third_party/rust/sync-guid/src/lib.rs b/third_party/rust/sync-guid/src/lib.rs
new file mode 100644
index 0000000000..f35f407f30
--- /dev/null
+++ b/third_party/rust/sync-guid/src/lib.rs
@@ -0,0 +1,482 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#![allow(unknown_lints)]
+#![warn(rust_2018_idioms)]
+// (It's tempting to avoid the utf8 checks, but they're easy to get wrong, so)
+#![deny(unsafe_code)]
+#[cfg(feature = "serde_support")]
+mod serde_support;
+
+#[cfg(feature = "rusqlite_support")]
+mod rusqlite_support;
+
+use std::{
+ cmp::Ordering,
+ fmt,
+ hash::{Hash, Hasher},
+ ops, str,
+};
+
+/// This is a type intended to be used to represent the guids used by sync. It
+/// has several benefits over using a `String`:
+///
+/// 1. It's more explicit about what is being stored, and could prevent bugs
+/// where a Guid is passed to a function expecting text.
+///
+/// 2. Guids are guaranteed to be immutable.
+///
+/// 3. It's optimized for the guids commonly used by sync. In particular, short guids
+/// (including the guids which would meet `PlacesUtils.isValidGuid`) do not incur
+/// any heap allocation, and are stored inline.
+#[derive(Clone)]
+pub struct Guid(Repr);
+
+// The internal representation of a GUID. Most Sync GUIDs are 12 bytes,
+// and contain only base64url characters; we can store them on the stack
+// without a heap allocation. However, arbitrary ascii guids of up to length 64
+// are possible, in which case we fall back to a heap-allocated string.
+//
+// This is separate only because making `Guid` an enum would expose the
+// internals.
+#[derive(Clone)]
+enum Repr {
+ // see FastGuid for invariants
+ Fast(FastGuid),
+
+ // invariants:
+ // - _0.len() > MAX_FAST_GUID_LEN
+ Slow(String),
+}
+
+/// Invariants:
+///
+/// - `len <= MAX_FAST_GUID_LEN`.
+/// - `data[0..len]` encodes valid utf8.
+/// - `data[len..].iter().all(|&b| b == b'\0')`
+///
+/// Note: None of these are required for memory safety, just correctness.
+#[derive(Clone)]
+struct FastGuid {
+ len: u8,
+ data: [u8; MAX_FAST_GUID_LEN],
+}
+
+// This is the maximum length (experimentally determined) we can make it before
+// `Repr::Fast` is larger than `Guid::Slow` on 32 bit systems. The important
+// thing is really that it's not too big, and is above 12 bytes.
+const MAX_FAST_GUID_LEN: usize = 14;
+
+impl FastGuid {
+ #[inline]
+ fn from_slice(bytes: &[u8]) -> Self {
+ // Checked by the caller, so debug_assert is fine.
+ debug_assert!(
+ can_use_fast(bytes),
+ "Bug: Caller failed to check can_use_fast: {:?}",
+ bytes
+ );
+ let mut data = [0u8; MAX_FAST_GUID_LEN];
+ data[0..bytes.len()].copy_from_slice(bytes);
+ FastGuid {
+ len: bytes.len() as u8,
+ data,
+ }
+ }
+
+ #[inline]
+ fn as_str(&self) -> &str {
+ // Note: we only use debug_assert! to enusre valid utf8-ness, so this need
+ str::from_utf8(self.bytes()).expect("Invalid fast guid bytes!")
+ }
+
+ #[inline]
+ fn len(&self) -> usize {
+ self.len as usize
+ }
+
+ #[inline]
+ fn bytes(&self) -> &[u8] {
+ &self.data[0..self.len()]
+ }
+}
+
+// Returns:
+// - true to use Repr::Fast
+// - false to use Repr::Slow
+#[inline]
+fn can_use_fast<T: ?Sized + AsRef<[u8]>>(bytes: &T) -> bool {
+ let bytes = bytes.as_ref();
+ // This is fine as a debug_assert since we'll still panic if it's ever used
+ // in such a way where it would matter.
+ debug_assert!(str::from_utf8(bytes).is_ok());
+ bytes.len() <= MAX_FAST_GUID_LEN
+}
+
+impl Guid {
+ /// Create a guid from a `str`.
+ #[inline]
+ pub fn new(s: &str) -> Self {
+ Guid::from_slice(s.as_ref())
+ }
+
+ /// Create an empty guid. Usable as a constant.
+ #[inline]
+ pub const fn empty() -> Self {
+ Guid(Repr::Fast(FastGuid {
+ len: 0,
+ data: [0u8; MAX_FAST_GUID_LEN],
+ }))
+ }
+
+ /// Create a random guid (of 12 base64url characters). Requires the `random`
+ /// feature.
+ #[cfg(feature = "random")]
+ pub fn random() -> Self {
+ let bytes: [u8; 9] = rand::random();
+
+ // Note: only first 12 bytes are used, but remaining are required to
+ // build the FastGuid
+ let mut output = [0u8; MAX_FAST_GUID_LEN];
+
+ let bytes_written =
+ base64::encode_config_slice(bytes, base64::URL_SAFE_NO_PAD, &mut output[..12]);
+
+ debug_assert!(bytes_written == 12);
+
+ Guid(Repr::Fast(FastGuid {
+ len: 12,
+ data: output,
+ }))
+ }
+
+ /// Convert `b` into a `Guid`.
+ #[inline]
+ pub fn from_string(s: String) -> Self {
+ Guid::from_vec(s.into_bytes())
+ }
+
+ /// Convert `b` into a `Guid`.
+ #[inline]
+ pub fn from_slice(b: &[u8]) -> Self {
+ if can_use_fast(b) {
+ Guid(Repr::Fast(FastGuid::from_slice(b)))
+ } else {
+ Guid::new_slow(b.into())
+ }
+ }
+
+ /// Convert `v` to a `Guid`, consuming it.
+ #[inline]
+ pub fn from_vec(v: Vec<u8>) -> Self {
+ if can_use_fast(&v) {
+ Guid(Repr::Fast(FastGuid::from_slice(&v)))
+ } else {
+ Guid::new_slow(v)
+ }
+ }
+
+ /// Get the data backing this `Guid` as a `&[u8]`.
+ #[inline]
+ pub fn as_bytes(&self) -> &[u8] {
+ match &self.0 {
+ Repr::Fast(rep) => rep.bytes(),
+ Repr::Slow(rep) => rep.as_ref(),
+ }
+ }
+
+ /// Get the data backing this `Guid` as a `&str`.
+ #[inline]
+ pub fn as_str(&self) -> &str {
+ match &self.0 {
+ Repr::Fast(rep) => rep.as_str(),
+ Repr::Slow(rep) => rep.as_ref(),
+ }
+ }
+
+ /// Convert this `Guid` into a `String`, consuming it in the process.
+ #[inline]
+ pub fn into_string(self) -> String {
+ match self.0 {
+ Repr::Fast(rep) => rep.as_str().into(),
+ Repr::Slow(rep) => rep,
+ }
+ }
+
+ /// Returns true for Guids that are deemed valid by the sync server.
+ /// See https://github.com/mozilla-services/server-syncstorage/blob/d92ef07877aebd05b92f87f6ade341d6a55bffc8/syncstorage/bso.py#L24
+ pub fn is_valid_for_sync_server(&self) -> bool {
+ !self.is_empty()
+ && self.len() <= 64
+ && self
+ .bytes()
+ .all(|b| (b' '..=b'~').contains(&b) && b != b',')
+ }
+
+ /// Returns true for Guids that are valid places guids, and false for all others.
+ pub fn is_valid_for_places(&self) -> bool {
+ self.len() == 12 && self.bytes().all(Guid::is_valid_places_byte)
+ }
+
+ /// Returns true if the byte `b` is a valid base64url byte.
+ #[inline]
+ pub fn is_valid_places_byte(b: u8) -> bool {
+ BASE64URL_BYTES[b as usize] == 1
+ }
+
+ #[cold]
+ fn new_slow(v: Vec<u8>) -> Self {
+ assert!(
+ !can_use_fast(&v),
+ "Could use fast for guid (len = {})",
+ v.len()
+ );
+ Guid(Repr::Slow(
+ String::from_utf8(v).expect("Invalid slow guid bytes!"),
+ ))
+ }
+}
+
+// This is used to implement the places tests.
+const BASE64URL_BYTES: [u8; 256] = [
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,
+ 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,
+ 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+];
+
+impl Ord for Guid {
+ fn cmp(&self, other: &Self) -> Ordering {
+ self.as_bytes().cmp(other.as_bytes())
+ }
+}
+
+impl PartialOrd for Guid {
+ fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+ Some(self.cmp(other))
+ }
+}
+
+impl PartialEq for Guid {
+ fn eq(&self, other: &Self) -> bool {
+ self.as_bytes() == other.as_bytes()
+ }
+}
+
+impl Eq for Guid {}
+
+impl Hash for Guid {
+ fn hash<H: Hasher>(&self, state: &mut H) {
+ self.as_bytes().hash(state);
+ }
+}
+
+impl<'a> From<&'a str> for Guid {
+ #[inline]
+ fn from(s: &'a str) -> Guid {
+ Guid::from_slice(s.as_ref())
+ }
+}
+impl<'a> From<&'a &str> for Guid {
+ #[inline]
+ fn from(s: &'a &str) -> Guid {
+ Guid::from_slice(s.as_ref())
+ }
+}
+
+impl<'a> From<&'a [u8]> for Guid {
+ #[inline]
+ fn from(s: &'a [u8]) -> Guid {
+ Guid::from_slice(s)
+ }
+}
+
+impl From<String> for Guid {
+ #[inline]
+ fn from(s: String) -> Guid {
+ Guid::from_string(s)
+ }
+}
+
+impl From<Vec<u8>> for Guid {
+ #[inline]
+ fn from(v: Vec<u8>) -> Guid {
+ Guid::from_vec(v)
+ }
+}
+
+impl From<Guid> for String {
+ #[inline]
+ fn from(guid: Guid) -> String {
+ guid.into_string()
+ }
+}
+
+impl From<Guid> for Vec<u8> {
+ #[inline]
+ fn from(guid: Guid) -> Vec<u8> {
+ guid.into_string().into_bytes()
+ }
+}
+
+impl AsRef<str> for Guid {
+ #[inline]
+ fn as_ref(&self) -> &str {
+ self.as_str()
+ }
+}
+
+impl AsRef<[u8]> for Guid {
+ #[inline]
+ fn as_ref(&self) -> &[u8] {
+ self.as_bytes()
+ }
+}
+
+impl ops::Deref for Guid {
+ type Target = str;
+ #[inline]
+ fn deref(&self) -> &str {
+ self.as_str()
+ }
+}
+
+// The default Debug impl is pretty unhelpful here.
+impl fmt::Debug for Guid {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ write!(f, "Guid({:?})", self.as_str())
+ }
+}
+
+impl fmt::Display for Guid {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ fmt::Display::fmt(self.as_str(), f)
+ }
+}
+
+impl std::default::Default for Guid {
+ /// Create a default guid by calling `Guid::empty()`
+ #[inline]
+ fn default() -> Self {
+ Guid::empty()
+ }
+}
+
+macro_rules! impl_guid_eq {
+ ($($other: ty),+) => {$(
+ // This macro is used for items with and without lifetimes.
+ #[allow(clippy::extra_unused_lifetimes)]
+ impl<'a> PartialEq<$other> for Guid {
+ #[inline]
+ fn eq(&self, other: &$other) -> bool {
+ PartialEq::eq(AsRef::<[u8]>::as_ref(self), AsRef::<[u8]>::as_ref(other))
+ }
+ }
+
+ #[allow(clippy::extra_unused_lifetimes)]
+ impl<'a> PartialEq<Guid> for $other {
+ #[inline]
+ fn eq(&self, other: &Guid) -> bool {
+ PartialEq::eq(AsRef::<[u8]>::as_ref(self), AsRef::<[u8]>::as_ref(other))
+ }
+ }
+ )+}
+}
+
+// Implement direct comparison with some common types from the stdlib.
+impl_guid_eq![str, &'a str, String, [u8], &'a [u8], Vec<u8>];
+
+#[cfg(test)]
+mod test {
+ use super::*;
+
+ #[test]
+ fn test_base64url_bytes() {
+ let mut expect = [0u8; 256];
+ for b in b'0'..=b'9' {
+ expect[b as usize] = 1;
+ }
+ for b in b'a'..=b'z' {
+ expect[b as usize] = 1;
+ }
+ for b in b'A'..=b'Z' {
+ expect[b as usize] = 1;
+ }
+ expect[b'_' as usize] = 1;
+ expect[b'-' as usize] = 1;
+ assert_eq!(&BASE64URL_BYTES[..], &expect[..]);
+ }
+
+ #[test]
+ fn test_valid_for_places() {
+ assert!(Guid::from("aaaabbbbcccc").is_valid_for_places());
+ assert!(Guid::from_slice(b"09_az-AZ_09-").is_valid_for_places());
+ assert!(!Guid::from("aaaabbbbccccd").is_valid_for_places()); // too long
+ assert!(!Guid::from("aaaabbbbccc").is_valid_for_places()); // too short
+ assert!(!Guid::from("aaaabbbbccc=").is_valid_for_places()); // right length, bad character
+ assert!(!Guid::empty().is_valid_for_places()); // empty isn't valid to insert.
+ }
+
+ #[test]
+ fn test_valid_for_sync_server() {
+ assert!(!Guid::empty().is_valid_for_sync_server()); // empty isn't valid remotely.
+ }
+
+ #[allow(clippy::cmp_owned)] // See clippy note below.
+ #[test]
+ fn test_comparison() {
+ assert_eq!(Guid::from("abcdabcdabcd"), "abcdabcdabcd");
+ assert_ne!(Guid::from("abcdabcdabcd".to_string()), "ABCDabcdabcd");
+
+ assert_eq!(Guid::from("abcdabcdabcd"), &b"abcdabcdabcd"[..]); // b"abcdabcdabcd" has type &[u8; 12]...
+ assert_ne!(Guid::from(&b"abcdabcdabcd"[..]), &b"ABCDabcdabcd"[..]);
+
+ assert_eq!(
+ Guid::from(b"abcdabcdabcd"[..].to_owned()),
+ "abcdabcdabcd".to_string()
+ );
+ assert_ne!(Guid::from("abcdabcdabcd"), "ABCDabcdabcd".to_string());
+
+ assert_eq!(
+ Guid::from("abcdabcdabcd1234"),
+ Vec::from(b"abcdabcdabcd1234".as_ref())
+ );
+ assert_ne!(
+ Guid::from("abcdabcdabcd4321"),
+ Vec::from(b"ABCDabcdabcd4321".as_ref())
+ );
+
+ // order by data instead of length
+ // hrmph - clippy in 1.54-nightly complains about the below:
+ // 'error: this creates an owned instance just for comparison'
+ // '... help: try: `*"aaaaaa"`'
+ // and suggests a change that's wrong - so we've ignored the lint above.
+ assert!(Guid::from("zzz") > Guid::from("aaaaaa"));
+ assert!(Guid::from("ThisIsASolowGuid") < Guid::from("zzz"));
+ assert!(Guid::from("ThisIsASolowGuid") > Guid::from("AnotherSlowGuid"));
+ }
+
+ #[cfg(feature = "random")]
+ #[test]
+ fn test_random() {
+ use std::collections::HashSet;
+ // Used to verify uniqueness within our sample of 1000. Could cause
+ // random failures, but desktop has the same test, and it's never caused
+ // a problem AFAIK.
+ let mut seen: HashSet<String> = HashSet::new();
+ for _ in 0..1000 {
+ let g = Guid::random();
+ assert_eq!(g.len(), 12);
+ assert!(g.is_valid_for_places());
+ let decoded = base64::decode_config(&g, base64::URL_SAFE_NO_PAD).unwrap();
+ assert_eq!(decoded.len(), 9);
+ let no_collision = seen.insert(g.clone().into_string());
+ assert!(no_collision, "{}", g);
+ }
+ }
+}
diff --git a/third_party/rust/sync-guid/src/rusqlite_support.rs b/third_party/rust/sync-guid/src/rusqlite_support.rs
new file mode 100644
index 0000000000..c4c0f2f042
--- /dev/null
+++ b/third_party/rust/sync-guid/src/rusqlite_support.rs
@@ -0,0 +1,23 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#![cfg(feature = "rusqlite_support")]
+
+use crate::Guid;
+use rusqlite::{
+ self,
+ types::{FromSql, FromSqlResult, ToSql, ToSqlOutput, ValueRef},
+};
+
+impl ToSql for Guid {
+ fn to_sql(&self) -> rusqlite::Result<ToSqlOutput<'_>> {
+ Ok(ToSqlOutput::from(self.as_str()))
+ }
+}
+
+impl FromSql for Guid {
+ fn column_result(value: ValueRef<'_>) -> FromSqlResult<Self> {
+ value.as_str().map(Guid::from)
+ }
+}
diff --git a/third_party/rust/sync-guid/src/serde_support.rs b/third_party/rust/sync-guid/src/serde_support.rs
new file mode 100644
index 0000000000..50220ffe12
--- /dev/null
+++ b/third_party/rust/sync-guid/src/serde_support.rs
@@ -0,0 +1,61 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#![cfg(feature = "serde_support")]
+
+use std::fmt;
+
+use serde::{
+ de::{self, Deserialize, Deserializer, Visitor},
+ ser::{Serialize, Serializer},
+};
+
+use crate::Guid;
+
+struct GuidVisitor;
+impl<'de> Visitor<'de> for GuidVisitor {
+ type Value = Guid;
+ #[inline]
+ fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+ formatter.write_str("a sync guid")
+ }
+ #[inline]
+ fn visit_str<E: de::Error>(self, s: &str) -> Result<Self::Value, E> {
+ Ok(Guid::from_slice(s.as_ref()))
+ }
+}
+
+impl<'de> Deserialize<'de> for Guid {
+ #[inline]
+ fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+ where
+ D: Deserializer<'de>,
+ {
+ deserializer.deserialize_str(GuidVisitor)
+ }
+}
+
+impl Serialize for Guid {
+ #[inline]
+ fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
+ serializer.serialize_str(self.as_str())
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use super::*;
+ use serde_test::{assert_tokens, Token};
+ #[test]
+ fn test_ser_de() {
+ let guid = Guid::from("asdffdsa12344321");
+ assert_tokens(&guid, &[Token::Str("asdffdsa12344321")]);
+
+ let guid = Guid::from("");
+ assert_tokens(&guid, &[Token::Str("")]);
+
+ let guid = Guid::from(&b"abcd43211234"[..]);
+ assert_tokens(&guid, &[Token::Str("abcd43211234")]);
+ }
+}