12 releases (6 stable)
2.0.0 | Apr 12, 2024 |
---|---|
1.2.1 | Apr 8, 2024 |
0.1.5 | Apr 1, 2024 |
#124 in Unix APIs
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19KB
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neocortex
Shared memory crate designed for simplicity, safety, and extensibility. With minimal dependencies on libc
and tracing
, this crate wraps unsafe shared memory operations in a user-friendly API.
Quick Start
Install using the (currently) only built-in lock implementation. See examples below for more instructions.
cargo add neocortex --features semaphore
System Requirements
- Operating System: Linux, macOS, or other UNIX-like operating systems.
- Dependencies: Users must ensure
libc
is available in their system's standard library.
Safety Guarantees
- Error Handling: As
libc
syscalls are inherently unsafe, no guarantees can be made that all allocated resources are properly cleaned up on a failure. This crate provides two error variants,CleanSystem
andDirtySystem
to indicate whether or not the error is leaving any dangling resources. All system errors also provides additional error information from the operating system on top of our custom error messages. - Error Logging: As an additional safety guarantee, all
DirtySystem
errors that are not properly handled (currently only in someDrop
implementations) will emit atracing::error!
event.
Features
- Simple API: Offers an easy-to-use interface for shared memory operations, abstracting
libc
complexities. - Clear Error Handling: Distinguishes between
Clean
andDirty
system errors. - Built-in Synchronization: Includes a semaphore-based lock for safe shared memory access. (requires crate feature "semaphore").
- Extendable: Flexibility to implement custom synchronization logic through the
CortexSync
trait.
Examples
Simple example using the built-in semaphore lock:
use neocortex::{Cortex, CortexBuilder, Semaphore};
// Initialize a segment of shared memory with the value 42.0
let key = 123;
let cortex = CortexBuilder::new(42.0)
.key(key)
.with_default_lock::<Semaphore>()
.unwrap();
// Attaching to an existing segment of shared memory requires explicit type annotations
let attached: Cortex<f64, Semaphore> = Cortex::attach(key).unwrap();
assert_eq!(cortex.read().unwrap(), attached.read().unwrap());
// Write to shared memory
let new_val = 12.34;
cortex.write(new_val).unwrap();
assert_eq!(cortex.read().unwrap(), new_val);
The semaphore
module comes with some pre-defined permissions, these permissions dictates which OS users can interact with the semaphore. Using with_default_lock
defaults to OwnerOnly
which is the most restrictive mode. Check out SemaphorePermission
for other modes, or use the Custom
enum-variant to set your own permissions.
use neocortex::{CortexBuilder, Semaphore, SemaphoreSettings, SemaphorePermission};
let settings = SemaphoreSettings {
mode: SemaphorePermission::OwnerAndGroup,
};
let cortex = CortexBuilder::new(42.0)
.key(123)
.with_lock::<Semaphore>(&settings)
.unwrap();
Dependencies
~315–465KB