ffi: Provide an interface to iterate over Keys in a TPK.

  - Add sq_tpk_key_iter, sq_tpk_key_iter_free, and sq_tpk_key_iter_next.

2 files changed, 72 insertions, 0 deletions

diff --git a/ffi/include/sequoia/openpgp.h b/ffi/include/sequoia/openpgp.h
index c39581c7..a46aa275 100644
--- a/ffi/include/sequoia/openpgp.h
+++ b/ffi/include/sequoia/openpgp.h
@@ -578,6 +578,28 @@ sq_user_id_binding_t sq_user_id_binding_iter_next (sq_user_id_binding_iter_t ite
 /// Frees an sq_user_id_binding_iter_t.
 void sq_user_id_binding_iter_free (sq_user_id_binding_iter_t iter);
 
+/* openpgp::tpk::KeyIter.  */
+
+/*/
+/// An iterator over keys in a TPK.
+/*/
+typedef struct sq_tpk_key_iter *sq_tpk_key_iter_t;
+
+/*/
+/// Returns a reference to the next element in the iterator.  Returns
+/// NULL if there are no more elements.
+///
+/// If signature is not NULL, stores a reference to the key's most
+/// recent self-signature, if any.  (Note: subkeys always have
+/// signatures, but a primary key may not have a direct signature, and
+/// there might not be any user ids.)
+/*/
+sq_p_key_t sq_tpk_key_iter_next (sq_tpk_key_iter_t iter,
+                                 sq_packet_t *signature);
+
+/// Frees an sq_tpk_key_iter_t.
+void sq_tpk_key_iter_free (sq_tpk_key_iter_t iter);
+
 /* openpgp::tpk.  */
 
 /*/
@@ -745,6 +767,12 @@ int sq_tpk_is_tsk(sq_tpk_t tpk);
 /*/
 sq_user_id_binding_iter_t sq_tpk_user_id_binding_iter (sq_tpk_t tpk);
 
+/*/
+/// Returns an iterator over all `Key`s (both the primary key and any
+/// subkeys) in a TPK.
+/*/
+sq_tpk_key_iter_t sq_tpk_key_iter (sq_tpk_t tpk);
+
 /* TPKBuilder */
 
 typedef struct sq_tpk_builder *sq_tpk_builder_t;
diff --git a/ffi/src/openpgp.rs b/ffi/src/openpgp.rs
index 34c96806..a531fec0 100644
--- a/ffi/src/openpgp.rs
+++ b/ffi/src/openpgp.rs
@@ -30,6 +30,7 @@ use self::openpgp::tpk::{
     TPKBuilder,
     UserIDBinding,
     UserIDBindingIter,
+    KeyIter
 };
 use self::openpgp::packet;
 use self::openpgp::parse::{PacketParserResult, PacketParser, PacketParserEOF};
@@ -1042,6 +1043,49 @@ pub extern "system" fn sq_user_id_binding_iter_next<'a>(
     iter.next()
 }
 
+/* tpk::KeyIter. */
+
+/// Returns an iterator over the TPK's keys.
+///
+/// This iterates over both the primary key and any subkeys.
+#[no_mangle]
+pub extern "system" fn sq_tpk_key_iter(tpk: Option<&TPK>)
+    -> *mut KeyIter
+{
+    let tpk = tpk.expect("TPK is NULL");
+    box_raw!(tpk.keys())
+}
+
+/// Frees a sq_tpk_key_iter_t.
+#[no_mangle]
+pub extern "system" fn sq_tpk_key_iter_free(
+    iter: *mut KeyIter)
+{
+    if iter.is_null() { return };
+    unsafe {
+        drop(Box::from_raw(iter))
+    };
+}
+
+/// Returns the next key.
+#[no_mangle]
+pub extern "system" fn sq_tpk_key_iter_next<'a>(
+    iter: Option<&mut KeyIter<'a>>,
+    sigo: Option<&mut *mut Option<&'a packet::Signature>>)
+    -> Option<&'a packet::Key>
+{
+    let iter = iter.expect("Iterator is NULL");
+    if let Some((sig, key)) = iter.next() {
+        if let Some(ptr) = sigo {
+            *ptr = box_raw!(sig);
+        }
+
+        Some(key)
+    } else {
+        None
+    }
+}
+
 /* TPKBuilder */
 
 /// Creates a default `sq_tpk_builder_t`.