From 68e2f46b89537d4af5db5bce3dc906a54ceb0eb9 Mon Sep 17 00:00:00 2001
From: Techatrix <techatrix@mailbox.org>
Date: Sat, 24 Jan 2026 22:31:57 +0100
Subject: [PATCH] add build option to enable thread safety

---
 build.zig | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/build.zig b/build.zig
index d8a9452..d32d981 100644
--- a/build.zig
+++ b/build.zig
@@ -7,6 +7,8 @@ pub fn build(b: *Build) void {
 
     const mbedtls_dep = b.dependency("mbedtls", .{});
 
+    const threading = b.option(bool, "threading", "Enable thread safety") orelse false;
+
     const mbedtls = b.addLibrary(.{
         .name = "mbedtls",
         .linkage = .static,
@@ -25,6 +27,10 @@ pub fn build(b: *Build) void {
         // Otherwise `explicit_bzero` cannot be found
         mbedtls.root_module.addCMacro("__BSD_VISIBLE", "1");
     }
+    if (threading) {
+        mbedtls.root_module.addCMacro("MBEDTLS_THREADING_C", "");
+        mbedtls.root_module.addCMacro("MBEDTLS_THREADING_PTHREAD", "");
+    }
 
     mbedtls.installHeadersDirectory(mbedtls_dep.path("include/mbedtls"), "mbedtls", .{});
     mbedtls.installHeadersDirectory(mbedtls_dep.path("include/psa"), "psa", .{});