Struct ContentDeduplicationIndex 

pub struct ContentDeduplicationIndex {
    pub config: ContentDedupConfig,
    /* private fields */
}

Hash-based content deduplication index.

Tracks identical content blocks, reference counts, and can reclaim storage by merging duplicates.

Example

use ipfrs_storage::content_dedup_index::{
    ContentDeduplicationIndex, ContentDedupConfig, ContentDedupResult,
};

let config = ContentDedupConfig::default();
let mut idx = ContentDeduplicationIndex::new(config);

let data = b"hello, world!";
let result = idx.insert("key1".into(), data, 1000).unwrap();
assert!(matches!(result, ContentDedupResult::New { .. }));

// Insert the same content under a different key — it's a duplicate
let result2 = idx.insert("key2".into(), data, 1001).unwrap();
assert!(matches!(result2, ContentDedupResult::Duplicate { .. }));

Fields

config: ContentDedupConfig

Runtime configuration.

Implementations

impl ContentDeduplicationIndex

pub fn new(config: ContentDedupConfig) -> Self

Create a new index with the supplied configuration.

pub fn compute_hash(data: &[u8]) -> ContentHash

Compute the 32-byte approximate ContentHash for data.

Layout:

• Bytes 0– 7: FNV-1a 64-bit
• Bytes 8–15: DJB2 64-bit xorshifted
• Bytes 16–23: data.len() as little-endian u64
• Bytes 24–31: FNV-1a 64-bit of reversed data

pub fn insert( &mut self, key: String, data: &[u8], now: u64, ) -> Result<ContentDedupResult, DedupIndexError>

Insert data under key into the deduplication index.

Returns:

• Ok(ContentDedupResult::New) when the content has not been seen before.
• Ok(ContentDedupResult::Duplicate) when identical content already exists.

Blocks whose size falls outside [min_block_size, max_block_size] are returned as New without modifying the index (pass-through behaviour).

pub fn remove(&mut self, key: &str) -> bool

Remove the key from the index.

Decrements the reference count of the associated entry; if the count reaches zero and no other key points to the same hash, the entry is removed entirely.

Returns true if key was present, false otherwise.

pub fn lookup_by_key(&self, key: &str) -> Option<&DedupEntry>

Look up a dedup entry by its storage key.

pub fn lookup_by_hash(&self, hash: &ContentHash) -> Option<&DedupEntry>

Look up a dedup entry directly by its content hash.

pub fn is_duplicate(&self, data: &[u8]) -> bool

Return true if data has been seen before (i.e., a matching hash exists in the index and the block size is within range).

pub fn merge_duplicates(&mut self) -> u64

Scan key_to_hash and count keys whose hash is already represented by a canonical key that differs from themselves. Returns the total number of duplicate key→hash mappings merged (conceptually deduplicated).

This method does not remove any data; it reports how many duplicate entries currently exist and is idempotent.

pub fn deduplicated_keys(&self) -> Vec<(&str, &str)>

Return all (duplicate_key, canonical_key) pairs where the duplicate key differs from the canonical key.

pub fn stats(&self) -> ContentDedupStats

Return a snapshot of index statistics.

pub fn len(&self) -> usize

Return the number of unique content hashes in the index.

pub fn is_empty(&self) -> bool

Return true when the index contains no entries.

pub fn key_count(&self) -> usize

Return the number of key→hash mappings (including duplicates).

Trait Implementations

impl Debug for ContentDeduplicationIndex

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.