In many logging scenarios, it is often useful to limit the logs to some maximum size while keeping only the most recent content. A common approach is to use a fixed-size circular buffer, where more space can be made for new content by deleting old content.

This crate supports one principle type, [StringRing], which is a circular buffer for UTF-8 encoded strings. Multiple [Granularity] modes are supported for various applications, which control how old content is removed.

Examples

The following is an example of the basic [Granularity::Character] mode:

```rust

use string_ring::*;

// example of a 16-byte circular string buffer let mut buf = StringRing::new(16, Granularity::Character); buf.push("hello world!"); asserteq!(buf.makecontiguous(), "hello world!"); buf.push("more content!"); asserteq!(buf.makecontiguous(), "ld!more content!"); ```

The following is an example of the [Granularity::Line] mode, which is often more useful for logging:

```rust

use string_ring::*;

// example of a 26-byte circular string buffer let mut buf = StringRing::new(26, Granularity::Line); buf.push("hello world!\n"); asserteq!(buf.makecontiguous(), "hello world!\n"); buf.push("more!\n"); asserteq!(buf.makecontiguous(), "hello world!\nmore!\n"); buf.push("too much!\n"); asserteq!(buf.makecontiguous(), "more!\ntoo much!\n"); ```

no-std

This crate supports building in no-std environments by disabling default features:

toml [dependencies] string-ring = { version = "...", use-default-features = false }

Note that the alloc crate is still required in this case, as there is not currently a heapless version of [StringRing].