From 28ae96f49fc8a46a74f76a3c41b978783890aff0 Mon Sep 17 00:00:00 2001
From: pedrocarlo <pedro.muniz.carlo@gmail.com>
Date: Thu, 17 Jul 2025 12:42:32 -0300
Subject: [PATCH] remove confusing casting from usize -> u16 -> usize for
 usable space

---
 core/storage/btree.rs          | 22 +++++++++++-----------
 core/storage/sqlite3_ondisk.rs |  8 ++++----
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/core/storage/btree.rs b/core/storage/btree.rs
index 1e83592a2..c2f747e73 100644
--- a/core/storage/btree.rs
+++ b/core/storage/btree.rs
@@ -837,8 +837,8 @@ impl BTreeCursor {
         page_type: PageType,
         usable_size: usize,
     ) -> Result<(usize, usize)> {
-        let max_local = payload_overflow_threshold_max(page_type, usable_size as u16);
-        let min_local = payload_overflow_threshold_min(page_type, usable_size as u16);
+        let max_local = payload_overflow_threshold_max(page_type, usable_size);
+        let min_local = payload_overflow_threshold_min(page_type, usable_size);
 
         // This matches btreeParseCellAdjustSizeForOverflow logic
         let n_local = if payload_len <= max_local {
@@ -2206,7 +2206,7 @@ impl BTreeCursor {
                         &mut cell_payload,
                         cell_idx,
                         record,
-                        self.usable_space() as u16,
+                        self.usable_space(),
                         self.pager.clone(),
                     );
 
@@ -4890,7 +4890,7 @@ impl BTreeCursor {
             &mut new_payload,
             cell_idx,
             record,
-            self.usable_space() as u16,
+            self.usable_space(),
             self.pager.clone(),
         );
 
@@ -6403,7 +6403,7 @@ fn fill_cell_payload(
     cell_payload: &mut Vec<u8>,
     cell_idx: usize,
     record: &ImmutableRecord,
-    usable_space: u16,
+    usable_space: usize,
     pager: Rc<Pager>,
 ) {
     // TODO: make record raw from start, having to serialize is not good
@@ -6498,13 +6498,13 @@ fn fill_cell_payload(
 /// - Give a minimum fanout of 4 for index b-trees
 /// - Ensure enough payload is on the b-tree page that the record header can usually be accessed
 ///   without consulting an overflow page
-pub fn payload_overflow_threshold_max(page_type: PageType, usable_space: u16) -> usize {
+pub fn payload_overflow_threshold_max(page_type: PageType, usable_space: usize) -> usize {
     match page_type {
         PageType::IndexInterior | PageType::IndexLeaf => {
-            ((usable_space as usize - 12) * 64 / 255) - 23 // Index page formula
+            ((usable_space - 12) * 64 / 255) - 23 // Index page formula
         }
         PageType::TableInterior | PageType::TableLeaf => {
-            usable_space as usize - 35 // Table leaf page formula
+            usable_space - 35 // Table leaf page formula
         }
     }
 }
@@ -6518,9 +6518,9 @@ pub fn payload_overflow_threshold_max(page_type: PageType, usable_space: u16) ->
 /// - Otherwise: store M bytes on page
 ///
 /// The remaining bytes are stored on overflow pages in both cases.
-pub fn payload_overflow_threshold_min(_page_type: PageType, usable_space: u16) -> usize {
+pub fn payload_overflow_threshold_min(_page_type: PageType, usable_space: usize) -> usize {
     // Same formula for all page types
-    ((usable_space as usize - 12) * 32 / 255) - 23
+    ((usable_space - 12) * 32 / 255) - 23
 }
 
 /// Drop a cell from a page.
@@ -8746,7 +8746,7 @@ mod tests {
             &mut payload,
             cell_idx as usize,
             &record,
-            pager.usable_space() as u16,
+            pager.usable_space(),
             pager.clone(),
         );
         insert_into_cell(
diff --git a/core/storage/sqlite3_ondisk.rs b/core/storage/sqlite3_ondisk.rs
index 3151136c6..979b2ef9f 100644
--- a/core/storage/sqlite3_ondisk.rs
+++ b/core/storage/sqlite3_ondisk.rs
@@ -622,9 +622,9 @@ impl PageContent {
         let cell_pointer = self.read_u16_no_offset(cell_pointer) as usize;
         let start = cell_pointer;
         let payload_overflow_threshold_max =
-            payload_overflow_threshold_max(self.page_type(), usable_size as u16);
+            payload_overflow_threshold_max(self.page_type(), usable_size);
         let payload_overflow_threshold_min =
-            payload_overflow_threshold_min(self.page_type(), usable_size as u16);
+            payload_overflow_threshold_min(self.page_type(), usable_size);
         let len = match self.page_type() {
             PageType::IndexInterior => {
                 let (len_payload, n_payload) = read_varint(&buf[cell_pointer + 4..]).unwrap();
@@ -879,8 +879,8 @@ pub fn read_btree_cell(
     usable_size: usize,
 ) -> Result<BTreeCell> {
     let page_type = page_content.page_type();
-    let max_local = payload_overflow_threshold_max(page_type, usable_size as u16);
-    let min_local = payload_overflow_threshold_min(page_type, usable_size as u16);
+    let max_local = payload_overflow_threshold_max(page_type, usable_size);
+    let min_local = payload_overflow_threshold_min(page_type, usable_size);
     match page_type {
         PageType::IndexInterior => {
             let mut pos = pos;