Add nonrelfile_utils.rs file

postgres_ffi/src/nonrelfile_utils.rs

@@ -0,0 +1,32 @@
+//!
+//! Common utilities for dealing with PostgreSQL non-relation files.
+//!
+use crate::pg_constants;
+use bytes::BytesMut;
+use log::*;
+
+pub fn transaction_id_set_status(xid: u32, status: u8, page: &mut BytesMut) {
+    trace!(
+        "handle_apply_request for RM_XACT_ID-{} (1-commit, 2-abort, 3-sub_commit)",
+        status
+    );
+
+    let byteno: usize = ((xid as u32 % pg_constants::CLOG_XACTS_PER_PAGE as u32)
+        / pg_constants::CLOG_XACTS_PER_BYTE) as usize;
+
+    let bshift: u8 =
+        ((xid % pg_constants::CLOG_XACTS_PER_BYTE) * pg_constants::CLOG_BITS_PER_XACT as u32) as u8;
+
+    page[byteno] =
+        (page[byteno] & !(pg_constants::CLOG_XACT_BITMASK << bshift)) | (status << bshift);
+}
+
+pub fn transaction_id_get_status(xid: u32, page: &[u8]) -> u8 {
+    let byteno: usize = ((xid as u32 % pg_constants::CLOG_XACTS_PER_PAGE as u32)
+        / pg_constants::CLOG_XACTS_PER_BYTE) as usize;
+
+    let bshift: u8 =
+        ((xid % pg_constants::CLOG_XACTS_PER_BYTE) * pg_constants::CLOG_BITS_PER_XACT as u32) as u8;
+
+    return ((page[byteno] >> bshift) & pg_constants::CLOG_XACT_BITMASK) as u8;
+}