scratchpad

A Rust library providing a stack-like dynamic memory pool with double-ended allocation support.

• Documentation
• Release notes

Features include:

• User-defined backing storage of data (static arrays, boxed slices, or mutable slice references).
• Allocation of any data type from any scratchpad instance.
• Double-ended allocation support (allocations from the "front" are separate from the "back", but share the same memory pool).
• Use of lifetimes to prevent dangling references to allocated data.
• Low runtime overhead.
• Support for no_std usage.

Usage

Add this to your Cargo.toml:

[dependencies]
scratchpad = "0.1"

and this to your crate root:

#[macro_use]
extern crate scratchpad;

Rust Version Support

The minimum supported Rust version is 1.25 due to use of the repr(align) attribute.

no_std Support

scratchpad doesn't require the Rust standard library, although it makes use of it by default (via the std crate feature) to provide support for using Box as backing memory. For no_std support, the std feature must be disabled in your Cargo.toml:

[dependencies]
scratchpad = { version = "0.1", default-features = false }

Box support is still available for no_std builds when using a nightly toolchain by enabling the unstable crate feature.

Unstable Features

The unstable crate feature provides some additional functionality when using a nightly toolchain:

• ByteData trait implementations for u128/i128.
• Declaration of the function Scratchpad::new() as const, allowing it to be used directly to initialize static variables (lazy_static crate or similar workaround needed otherwise).
• Support for using Box as the storage type for allocations and marker tracking, regardless of whether the std feature is enabled (alloc library is used if std is disabled).

Simply add the unstable feature to your Cargo.toml dependency:

[dependencies]
scratchpad = { version = "0.1", features = ["unstable"] }