1 files changed, 39 insertions, 0 deletions
diff --git a/src/pam.rs b/src/pam.rs
new file mode 100644
index 0000000..17e4590
--- /dev/null
+++ b/src/pam.rs
@@ -0,0 +1,39 @@
+use core::marker::{PhantomData, PhantomPinned};
+use std::ffi::{c_char, c_int, CStr, CString};
+
+#[repr(C)]
+pub struct PAMHandle {
+    _data: [u8; 0],
+    _marker: PhantomData<(*mut u8, PhantomPinned)>,
+}
+
+pub const SUCCESS: c_int = 0;
+pub const SESSION_ERR: c_int = 14;
+
+extern "C" {
+    fn pam_get_user(
+        pamh: *const PAMHandle,
+        user: &*const c_char,
+        prompt: *const c_char,
+    ) -> c_int;
+}
+
+impl PAMHandle {
+    pub fn get_user<S: AsRef<CStr> + ?Sized>(
+        &self,
+        prompt: Option<&S>,
+    ) -> Result<CString, c_int> {
+        let ptr: *const c_char = std::ptr::null_mut();
+        let prompt = match prompt {
+            Some(prompt) => prompt.as_ref().as_ptr(),
+            None => core::ptr::null(),
+        };
+        match unsafe { pam_get_user(self, &ptr, prompt) } {
+            SUCCESS if !ptr.is_null() => {
+                let cstr = unsafe { CStr::from_ptr(ptr) };
+                Ok(CString::from(cstr))
+            }
+            e => Err(e),
+        }
+    }
+}