fix: adjust close_handles pointer offsets to match distlib cleanup_fds

crates/uv-trampoline/src/bounce.rs

@@ -344,17 +344,23 @@ fn close_handles(si: &STARTUPINFOA) {
     if si.cbReserved2 == 0 || si.lpReserved2.is_null() {
         return;
     }
+
     let crt_magic = si.lpReserved2 as *const u32;
     let handle_count = unsafe { crt_magic.read_unaligned() } as isize;
-    let handle_start = unsafe { crt_magic.offset(1 + handle_count) };
-    for i in 0..handle_count {
-        let handle = HANDLE(unsafe { handle_start.offset(i).read_unaligned() as _ });
-        // Close all fds inherited from the parent, except for the standard I/O fds.
-        if !handle.is_invalid() {
-            unsafe { CloseHandle(handle) }.unwrap_or_else(|_| {
-                eprintln!("Failed to close child file descriptors at {}", i);
-            });
+    let handle_start =
+        unsafe { (crt_magic.offset(1) as *const u8).offset(handle_count) as *const HANDLE };
+
+    // Close all fds inherited from the parent, except for the standard I/O fds (skip first 3).
+    for i in 3..handle_count {
+        let handle = unsafe { handle_start.offset(i).read_unaligned() };
+        // Ignore invalid handles, as that means this fd was not inherited.
+        // -2 is a special value (https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/get-osfhandle)
+        if handle.is_invalid() || handle.0 == -2 as _ {
+            continue;
         }
+        unsafe { CloseHandle(handle) }.unwrap_or_else(|_| {
+            eprintln!("Failed to close child file descriptors at {}", i);
+        });
     }
 }