问题最可能是由于未使用正确的内存分配和释放方式引起的。在Rust中,CString必须使用from_raw和into_raw函数来正确地分配和释放内存。
以下是一些示例代码,说明如何正确使用from_raw和into_raw函数,以避免这种崩溃问题:
在Rust中:
use std::os::raw::c_char;
use std::ffi::CString;
use libc::{free, size_t};
#[no_mangle]
pub extern "C" fn allocate_string(size: size_t) -> *mut c_char {
let mut buffer: Vec<u8> = Vec::with_capacity(size as usize);
buffer.set_len(size as usize);
let c_string = CString::from_vec_unchecked(buffer);
c_string.into_raw()
}
#[no_mangle]
pub extern "C" fn deallocate_string(c_string: *mut c_char) {
unsafe {
CString::from_raw(c_string);
}
}
在LabVIEW中:
; Allocate memory for a C string in Rust
; Returns a pointer to the allocated C string
Function Allocate CString (size : Int32) => (pointer : Int_PTR)
; Rust function name and parameter types
FCallAllocateCString = New Call Library Function Node("rust.dll", "allocate_string(size : u64) -> *mut i8")
; Call Rust function with size parameter
[pointer] = Call(FCallAllocateCString, Int64(size))
End Function
; Deallocate memory for a C string in Rust
; Takes a pointer to a C string allocated in Rust
Function Deallocate CString (pointer : Int_PTR)
; Rust function name and parameter types
FCallDeallocateCString = New Call Library Function Node("rust.dll", "deallocate_string(c_string : *mut i8)")
; Call Rust function with pointer parameter
Call(FCallDeallocateCString, pointer)
End Function
如果在使用CString时遵循这些最佳实践,就可以避免LabVIEW在Rust释放CString时崩溃的问题。