feat: Added age-ffi.

zig-vendor/age-ffi/src/helpers.rs

@@ -0,0 +1,27 @@
+//! Internal helper functions for FFI conversions.
+
+use crate::types::AgeResult;
+use std::ffi::{CStr, CString};
+use std::os::raw::c_char;
+
+/// Safely convert a C string pointer to a Rust &str
+pub unsafe fn cstr_to_str<'a>(ptr: *const c_char) -> Result<&'a str, AgeResult> {
+    if ptr.is_null() {
+        return Err(AgeResult::InvalidInput);
+    }
+    CStr::from_ptr(ptr)
+        .to_str()
+        .map_err(|_| AgeResult::InvalidUtf8)
+}
+
+/// Safely convert a C string pointer to a Rust String
+pub unsafe fn cstr_to_string(ptr: *const c_char) -> Result<String, AgeResult> {
+    cstr_to_str(ptr).map(|s| s.to_owned())
+}
+
+/// Convert a Rust String to a C string pointer (caller must free)
+pub fn string_to_cstr(s: String) -> Result<*mut c_char, AgeResult> {
+    CString::new(s)
+        .map(|cs| cs.into_raw())
+        .map_err(|_| AgeResult::InvalidInput)
+}