start to unclutter low-level macros

Author: molpopgen

src/lib.rs

@@ -92,6 +92,7 @@ mod node_table;
 mod population_table;
 pub mod prelude;
 mod site_table;
+mod sys;
 mod table_collection;
 mod table_iterator;
 pub mod table_views;

src/node_table.rs

@@ -2,6 +2,7 @@ use std::ptr::NonNull;
 
 use crate::bindings as ll_bindings;
 use crate::metadata;
+use crate::sys;
 use crate::NodeFlags;
 use crate::SizeType;
 use crate::Time;
@@ -195,7 +196,7 @@ impl NodeTable {
     /// # }
     /// ```
     pub fn time<N: Into<NodeId> + Copy>(&self, row: N) -> Option<Time> {
-        unsafe_tsk_column_access!(row.into(), 0, self.num_rows(), self.as_ref(), time, Time)
+        sys::tsk_column_access::<Time, _, _, _>(row.into(), self.as_ref().time, self.num_rows())
     }
 
     /// Return the ``flags`` value from row ``row`` of the table.

src/sys.rs

@@ -0,0 +1,24 @@
+use crate::bindings;
+
+pub fn tsk_column_access<
+    O: From<T>,
+    R: Into<bindings::tsk_id_t>,
+    L: Into<bindings::tsk_size_t>,
+    T: Copy,
+>(
+    row: R,
+    column: *const T,
+    column_length: L,
+) -> Option<O> {
+    let row = row.into();
+    let column_length = column_length.into();
+    if row < 0 || (row as crate::tsk_size_t) >= column_length {
+        None
+    } else {
+        assert!(!column.is_null());
+        // SAFETY: pointer is not null.
+        // column_length is assumed to come directly
+        // from a table.
+        Some(unsafe { *column.offset(row as isize) }.into())
+    }
+}