# sdoppia
A CLI tool to scan directories, hash files, and find duplicate files.
`sdoppia` walks one or more directories, SHA-256
hashes every file, stores the results in a local SQLite database, and reports
duplicate groups with the space they waste. On rescan, unchanged files (same
size and modification time) are skipped using cached hashes, so repeat scans
are fast.
## Installation
From crates.io:
```sh
cargo install sdoppia
```
Or from source:
```sh
cargo install --path .
```
## Usage
```
sdoppia [OPTIONS] <COMMAND>
Commands:
scan Scan directories and hash all files
clear Clear all entries from the database
stats Show database statistics
Options:
-v, --verbose Enable verbose logging
-h, --help Print help
-V, --version Print version
```
### Scan
```
sdoppia scan [OPTIONS] <PATHS>...
Arguments:
<PATHS>... Directories to scan (can specify multiple)
Options:
-d, --db <DB> Database file path [default: sdoppia.db]
-L, --follow-links Follow symbolic links
-r, --rehash Force rehashing of files already in database
-o, --output <OUTPUT> Output file for duplicates (optional, prints to stdout if not provided)
-m, --min-size <MIN_SIZE> Minimum file size in bytes to include in export [default: 0]
```
## Examples
Scan a directory and print the duplicate report to stdout:
```sh
sdoppia scan ~/Documents
```
Scan multiple paths and write the report to a file:
```sh
sdoppia scan ~/Documents ~/Downloads --output duplicates.txt
```
Only report duplicates larger than 1 MB:
```sh
sdoppia scan ~/Documents --min-size 1048576
```
Force rehashing of files already in the database:
```sh
sdoppia scan ~/Documents --rehash
```
Follow symbolic links while scanning:
```sh
sdoppia scan ~/Documents --follow-links
```
Use a custom database file (default is `sdoppia.db` in the current directory):
```sh
sdoppia scan ~/Documents --db /path/to/sdoppia.db
```
Show database statistics:
```sh
sdoppia stats
```
Clear all entries from the database:
```sh
sdoppia clear
```
## Example report
```
=== DUPLICATE FILES REPORT ===
Generated: 2026-08-19 21:30:00
Total duplicate files: 1
Wasted space: 12 bytes
Duplicate groups: 1
--- Group 1 ---
Hash: a948904f2f0f479b8f8197694b30184b0d2ed1c1cd2a1ec0fb85d299a192a447
Size: 12 bytes
Copies: 2
Wasted: 12 bytes
Files:
- /home/user/docs/a.txt
- /home/user/docs/b.txt
```
## How it works
1. **Scan** — walk the given paths and collect file metadata (path, size,
modification time).
2. **Filter** — for each file, check the database: if the size and
modification time match a cached entry, reuse the stored hash; otherwise
queue the file for hashing.
3. **Hash** — SHA-256 hash queued files in parallel.
4. **Store** — batch-insert hashes into the SQLite database.
5. **Report** — group files by hash and list groups with more than one copy.
## Exit codes
- `0` — success
- `1` — error (e.g. a scan path does not exist, database failure)
## Development
```sh
cargo test # unit and CLI integration tests
cargo clippy --all-targets -- -D warnings
cargo fmt --check
```