refactor: safe sql access

src/keyring.rs

@@ -4,7 +4,6 @@ use crate::constants::*;
 use crate::context::Context;
 use crate::dc_sqlite3::*;
 use crate::key::*;
-use crate::types::*;
 
 #[derive(Default, Clone, Debug)]
 pub struct Keyring<'a> {
@@ -31,29 +30,18 @@ impl<'a> Keyring<'a> {
     pub fn load_self_private_for_decrypting(
         &mut self,
         context: &Context,
-        self_addr: *const libc::c_char,
+        self_addr: impl AsRef<str>,
         sql: &SQLite,
     ) -> bool {
-        // Can we prevent keyring and self_addr to be null?
-        if self_addr.is_null() {
-            return false;
-        }
-        let stmt = unsafe {
-            dc_sqlite3_prepare(
-                context,
-                sql,
-                b"SELECT private_key FROM keypairs ORDER BY addr=? DESC, is_default DESC;\x00"
-                    as *const u8 as *const libc::c_char,
-            )
-        };
-        unsafe { sqlite3_bind_text(stmt, 1, self_addr, -1, None) };
-        while unsafe { sqlite3_step(stmt) == 100 } {
-            if let Some(key) = Key::from_stmt(stmt, 0, KeyType::Private) {
-                self.add_owned(key);
-            }
-        }
-        unsafe { sqlite3_finalize(stmt) };
-
-        true
+        dc_sqlite3_query_row(
+            context,
+            sql,
+            "SELECT private_key FROM keypairs ORDER BY addr=? DESC, is_default DESC;",
+            &[self_addr.as_ref()],
+            0,
+        )
+        .and_then(|blob: Vec<u8>| Key::from_slice(&blob, KeyType::Private))
+        .map(|key| self.add_owned(key))
+        .is_some()
     }
 }