opaque-pointer-rs

Generic functions to work with opaque pointers when use FFI to expose Rust structs

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Basic usage

With this crate you can manage raw pointers easily to expose structs that will be use as opaque pointers from C or C++ calling to Rust functions to use it. This can be used with cbindgen crate with option parse.parse_deps = true for it will generate opaque C/C++ structs to use pointers in the arguments. You can find more information in The Rust FFI Omnibus objects section of Jake Goulding.

Example: ```rust struct TestIt { value: u8, }

impl TestIt { pub fn new(value: u8) -> Self { Self { value, } } pub fn add(&mut self, value: u8) { self.value += value; } pub fn get(&self) -> u8 { self.value } }

/// TestIt new method.

[no_mangle]

pub extern fn testitnew(value: u8) -> *mut TestIt { opaquepointer::raw(TestIt::new(testit)) }

/// TestIt add method.

[no_mangle]

pub extern fn testitadd(testit: *mut TestIt, value: u8) { let testit = unsafe { opaquepointer::mut_object(testit) }; testit.add(value); }

/// TestIt get method.

[no_mangle]

pub extern fn testitget(testit: *const TestIt) -> u8 { let testit = unsafe { opaquepointer::object(testit) }; testit.get() }

/// TestIt free.

[no_mangle]

pub extern fn testitfree(testit: *const TestIt) { unsafe { opaquepointer::free(testit) } } ```