From 998c2ddf2041f7b5ba6760131ac2db865007500d Mon Sep 17 00:00:00 2001
From: Yuta Saito <kateinoigakukun@gmail.com>
Date: Mon, 1 Jul 2024 23:24:40 +0900
Subject: [PATCH] Fix module file reading on Windows

`open` on Windows uses "text-mode", so we need to explicitly specify
O_BINARY.
---
 Sources/WasmKit/ModuleParser.swift | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/Sources/WasmKit/ModuleParser.swift b/Sources/WasmKit/ModuleParser.swift
index 92a819d4..64eb94f1 100644
--- a/Sources/WasmKit/ModuleParser.swift
+++ b/Sources/WasmKit/ModuleParser.swift
@@ -1,10 +1,30 @@
 import SystemPackage
 import WasmParser
 
+#if os(Windows)
+import ucrt
+
+extension FileDescriptor.AccessMode {
+    static var binary: FileDescriptor.AccessMode {
+        FileDescriptor.AccessMode(rawValue: O_BINARY)
+    }
+}
+
+#endif
+
+
 /// Parse a given file as a WebAssembly binary format file
 /// > Note: <https://webassembly.github.io/spec/core/binary/index.html>
 public func parseWasm(filePath: FilePath, features: WasmFeatureSet = .default) throws -> Module {
-    let fileHandle = try FileDescriptor.open(filePath, .readOnly)
+    #if os(Windows)
+    // TODO: Upstream `O_BINARY` to `SystemPackage
+    let accessMode = FileDescriptor.AccessMode(
+        rawValue: FileDescriptor.AccessMode.readOnly.rawValue | FileDescriptor.AccessMode.binary.rawValue
+    )
+    #else
+    let accessMode: FileDescriptor.AccessMode = .readOnly
+    #endif
+    let fileHandle = try FileDescriptor.open(filePath, accessMode)
     defer { try? fileHandle.close() }
     let stream = try FileHandleStream(fileHandle: fileHandle)
     let module = try parseModule(stream: stream, features: features)