From b28cdfbcf4458e603043fbfd608d4baf97559664 Mon Sep 17 00:00:00 2001
From: Michael Chiu <m_chiu@apple.com>
Date: Mon, 6 Jan 2025 18:17:17 -0800
Subject: [PATCH] use closefrom(2) on platforms supports it to reduce race
 condition window

---
 Sources/Commands/SwiftRunCommand.swift | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Sources/Commands/SwiftRunCommand.swift b/Sources/Commands/SwiftRunCommand.swift
index 5bc94fb8bdc..1acf3ddebaa 100644
--- a/Sources/Commands/SwiftRunCommand.swift
+++ b/Sources/Commands/SwiftRunCommand.swift
@@ -312,16 +312,20 @@ public struct SwiftRunCommand: AsyncSwiftCommand {
         sigfillset(&sig_set_all)
         sigprocmask(SIG_UNBLOCK, &sig_set_all, nil)
 
+        #if os(FreeBSD) || os(OpenBSD)
+        closefrom(3)
+        #else
         #if os(Android)
         let number_fds = Int32(sysconf(_SC_OPEN_MAX))
         #else
         let number_fds = getdtablesize()
-        #endif
+        #endif /* os(Android) */
         
         // 2. close all file descriptors.
         for i in 3..<number_fds {
             close(i)
         }
+        #endif /* os(FreeBSD) || os(OpenBSD) */
         #endif
 
         try TSCBasic.exec(path: path, args: args)