Crate ddsavelib

A library to decode and encode the binary Darkest Dungeon save file format.

The library can convert between the binary representation used by the game and a JSON representation.

The File type represents a Darkest Dungeon save file. An Unhasher containing game data names can be provided to the File to JSON conversion to make save files more easily legible and editable. name_hash is a utility to calculate the hash of a string according to the DD hashing algorithm.

use ddsavelib::{File, Unhasher};

let json = r#"{ "__revision_dont_touch": 12345,
                "base_root": { "soldier_class": -2101527251 }
           }"#;

// Read the JSON file
let file1 = File::try_from_json(&mut json.as_bytes()).unwrap();

// Convert to binary
let mut bin_data = Vec::new();
file1.write_to_bin(&mut bin_data).unwrap();

// Realize we know Jester is a class
let mut unhash = Unhasher::empty();
unhash.offer_name("jester");

// Convert to JSON
let mut json_data = Vec::new();
let file2 = File::try_from_bin(&mut &*bin_data).unwrap();
file2.write_to_json(&mut json_data, true, &unhash).unwrap();
let output_str = std::str::from_utf8(&json_data).unwrap().replace(" ", "").replace("\n", "");

// We even managed to unhash Jester!
assert_eq!(&*output_str,
  r####"{"__revision_dont_touch":12345,"base_root":{"soldier_class":"###jester"}}"####);

// The library performs verification of the input and doesn't panic.
let mut garbage_data: &[u8] = &[0u8, 50u8, 145u8, 2u8];
assert!(File::try_from_bin(&mut garbage_data).is_err());

Darkest Dungeon save files usually have a base_root root field. The __revision_dont_touch field is inserted and expected by the library, as this is the single header field that cannot be deduced from the files’ contents.

Features

• string_cache (default: yes): Uses the string_cache crate to intern strings, yielding a performance boost for decoding binary files.

Modules

• err
  Provides the various errors that can occur when deserializing from Binary or JSON.

Structs

• File
  Represents a valid Darkest Dungeon save file.
• Unhasher
  A map from name hash -> name to make the JSON format more legible.

Functions

• name_hash
  Calculate the hash of a given string according to the DD hashing algorithm.