From 927ae8959c8c4ed44cc78a8ffd1e8ed5b4609064 Mon Sep 17 00:00:00 2001
From: CPTforever <yester1324@gmail.com>
Date: Thu, 1 Aug 2024 21:55:51 +0000
Subject: [PATCH] Added compaction to fd allocator

---
 src/lib/twizzler-abi/src/runtime/fs.rs | 24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/lib/twizzler-abi/src/runtime/fs.rs b/src/lib/twizzler-abi/src/runtime/fs.rs
index 168be496..8fa4aa88 100644
--- a/src/lib/twizzler-abi/src/runtime/fs.rs
+++ b/src/lib/twizzler-abi/src/runtime/fs.rs
@@ -70,13 +70,23 @@ impl RustFsRuntime for MinimalRuntime {
             } };
         }
 
-        let fd = get_fd_slots()
-            .lock()
-            .push(Arc::new(Mutex::new(FileDesc {
-                slot_id: 0,
-                pos: 0,
-                handle: handle
-            })));
+        let mut binding = get_fd_slots()
+            .lock();
+
+        let elem = Arc::new(Mutex::new(FileDesc {
+            slot_id: 0,
+            pos: 0,
+            handle: handle
+        }));
+        
+        let fd = if binding.is_compact() {
+            binding.push(elem)
+        }
+        else {
+            let fd = binding.first_empty_slot_from(0).unwrap();
+            binding.insert(fd, elem);
+            fd
+        };
 
         Ok (fd.try_into().unwrap())
     }