lv2rs_core/
lib.rs

1//! This crate contains the complete contents of the
2//! [LV2 core library](http://lv2plug.in/ns/lv2core/lv2core.html) with additional constructions
3//! to make the use of LV2 as idiomatic and safe as possible.
4//! 
5//! This is a frozen prototype and therefore, development of this crate will not continue here. Further
6//! development continues as [rust-lv2](https://github.com/rust-dsp/rust-lv2).
7mod feature;
8mod plugin;
9pub mod ports;
10pub mod uris;
11
12pub use feature::{Feature, FeaturesList};
13pub use plugin::*;
14
15/// Create lv2 export functions.
16///
17/// This macro takes a struct that implements [`Plugin`](trait.Plugin.html) and creates the required
18/// functions a plugin needs to export in order to be found and used by plugin hosts.
19///
20/// In order to properly work, it needs three arguments:
21/// * The namespace of the `lv2rs-core` crate: You may use this crate via re-exports and
22/// therefore, the name of the namespace is needed in order to call the appropiate functions.
23/// * The struct type that should be used as the Plugin implementation.
24/// * The URI of the plugin. Please note that the URI needs to be a bytes-array and null-terminated,
25/// since the C world has to interact with it.
26///     
27///       extern crate lv2rs_core as lv2core;
28///       use std::ffi::CStr;
29///       use lv2core::ports::*;
30///     
31///       struct MyPlugin {}
32///
33///       impl lv2core::Plugin for MyPlugin {
34///           fn instantiate(
35///               _descriptor: &lv2core::Descriptor,
36///               _rate: f64,
37///               _bundle_path: &CStr,
38///               _features: Option<&lv2core::FeaturesList>
39///           ) -> Option<Self> {
40///               Some(Self {})
41///           }
42///
43///           fn connect_port(&mut self, _port: u32, _data: *mut ()) {}
44///
45///           fn run(&mut self, _n_samples: u32) {}
46///       }
47///
48///       lv2core::lv2_main!(lv2core, MyPlugin, b"http://example.org/Dummy\0");
49///
50#[macro_export]
51macro_rules! lv2_main {
52    ($c:ident, $s:ty, $u:expr) => {
53        const PLUGIN_URI: &'static [u8] = $u;
54        const PLUGIN_DESCRIPTOR: $c::Descriptor = $c::Descriptor {
55            uri: PLUGIN_URI.as_ptr() as *const std::os::raw::c_char,
56            instantiate: instantiate,
57            connect_port: connect_port,
58            activate: activate,
59            run: run,
60            deactivate: deactivate,
61            cleanup: cleanup,
62            extension_data: extension_data,
63        };
64
65        unsafe extern "C" fn instantiate(
66            descriptor: *const $c::Descriptor,
67            rate: f64,
68            bundle_path: *const std::os::raw::c_char,
69            features: *const *const $c::Feature,
70        ) -> $c::Handle {
71            $c::instantiate::<$s>(descriptor, rate, bundle_path, features)
72        }
73
74        unsafe extern "C" fn connect_port(
75            instance: $c::Handle,
76            port: u32,
77            data: *mut std::os::raw::c_void,
78        ) {
79            $c::connect_port::<$s>(instance, port, data);
80        }
81
82        unsafe extern "C" fn activate(instance: $c::Handle) {
83            $c::activate::<$s>(instance);
84        }
85
86        unsafe extern "C" fn run(instance: $c::Handle, n_samples: u32) {
87            $c::run::<$s>(instance, n_samples);
88        }
89
90        unsafe extern "C" fn deactivate(instance: $c::Handle) {
91            $c::deactivate::<$s>(instance);
92        }
93
94        unsafe extern "C" fn cleanup(instance: $c::Handle) {
95            $c::cleanup::<$s>(instance);
96        }
97
98        unsafe extern "C" fn extension_data(
99            uri: *const std::os::raw::c_char,
100        ) -> *const std::os::raw::c_void {
101            $c::extension_data::<$s>(uri)
102        }
103
104        #[no_mangle]
105        pub unsafe extern "C" fn lv2_descriptor(index: u32) -> *const $c::Descriptor {
106            if index == 0 {
107                &PLUGIN_DESCRIPTOR
108            } else {
109                std::ptr::null()
110            }
111        }
112    };
113}
lv2rs_core/lib.rs

lv2rs_core/
lib.rs
