From 511ec846b66e39447acbd021083b26ca2747a188 Mon Sep 17 00:00:00 2001
From: Bryan Mills <bcmills@google.com>
Date: Tue, 30 Jan 2024 20:37:30 +0000
Subject: [PATCH] Revert "windows: support nil done parameter in ReadFile and
 WriteFile"

This reverts CL 559375.

Reason for revert: introduced a different regression (golang/go#65378).

Fixes golang/go#65378.
Updates golang/go#65365.

Change-Id: Ie2a602415913b04b9d9b65fee5c6a54c0267b35e
Cq-Include-Trybots: luci.golang.try:x_sys-gotip-windows-amd64-longtest
Reviewed-on: https://go-review.googlesource.com/c/sys/+/559502
Auto-Submit: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
---
 windows/syscall_windows.go      | 20 ++++--------
 windows/syscall_windows_test.go | 55 ---------------------------------
 2 files changed, 6 insertions(+), 69 deletions(-)

diff --git a/windows/syscall_windows.go b/windows/syscall_windows.go
index ea7a11908..ffb8708cc 100644
--- a/windows/syscall_windows.go
+++ b/windows/syscall_windows.go
@@ -572,17 +572,13 @@ func Write(fd Handle, p []byte) (n int, err error) {
 }
 
 func ReadFile(fd Handle, p []byte, done *uint32, overlapped *Overlapped) error {
-	var n uint32
-	err := readFile(fd, p, &n, overlapped)
+	err := readFile(fd, p, done, overlapped)
 	if raceenabled {
-		if n > 0 {
-			raceWriteRange(unsafe.Pointer(&p[0]), int(n))
+		if *done > 0 {
+			raceWriteRange(unsafe.Pointer(&p[0]), int(*done))
 		}
 		raceAcquire(unsafe.Pointer(&ioSync))
 	}
-	if done != nil {
-		*done = n
-	}
 	return err
 }
 
@@ -590,13 +586,9 @@ func WriteFile(fd Handle, p []byte, done *uint32, overlapped *Overlapped) error
 	if raceenabled {
 		raceReleaseMerge(unsafe.Pointer(&ioSync))
 	}
-	var n uint32
-	err := writeFile(fd, p, &n, overlapped)
-	if raceenabled && n > 0 {
-		raceReadRange(unsafe.Pointer(&p[0]), int(n))
-	}
-	if done != nil {
-		*done = n
+	err := writeFile(fd, p, done, overlapped)
+	if raceenabled && *done > 0 {
+		raceReadRange(unsafe.Pointer(&p[0]), int(*done))
 	}
 	return err
 }
diff --git a/windows/syscall_windows_test.go b/windows/syscall_windows_test.go
index a360535e0..665837907 100644
--- a/windows/syscall_windows_test.go
+++ b/windows/syscall_windows_test.go
@@ -1275,58 +1275,3 @@ uintptr_t beep(void) {
 		t.Fatal("LoadLibraryEx unexpectedly found beep.dll")
 	}
 }
-
-func TestReadWriteFileOverlapped(t *testing.T) {
-	name := filepath.Join(t.TempDir(), "test.txt")
-	fd, err := windows.CreateFile(windows.StringToUTF16Ptr(name), windows.GENERIC_READ|windows.GENERIC_WRITE, 0, nil, windows.CREATE_NEW, windows.FILE_FLAG_OVERLAPPED, 0)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer windows.CloseHandle(fd)
-
-	content := []byte("hello")
-	// Test that we can write to a file using overlapped I/O.
-	var ow windows.Overlapped
-	ow.HEvent, err = windows.CreateEvent(nil, 0, 0, nil)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer windows.CloseHandle(ow.HEvent)
-	if err := windows.WriteFile(fd, content, nil, &ow); err != nil && err != windows.ERROR_IO_PENDING {
-		t.Fatal(err)
-	}
-	if _, err := windows.WaitForSingleObject(ow.HEvent, windows.INFINITE); err != nil {
-		t.Fatal(err)
-	}
-	var n uint32
-	if err := windows.GetOverlappedResult(fd, &ow, &n, true); err != nil {
-		t.Fatal(err)
-	}
-	if n != uint32(len(content)) {
-		t.Fatalf("got %d bytes written; want %d", n, len(content))
-	}
-
-	// Test that we can read from a file using overlapped I/O.
-	var or windows.Overlapped
-	or.HEvent, err = windows.CreateEvent(nil, 0, 0, nil)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer windows.CloseHandle(ow.HEvent)
-	buf := make([]byte, len(content))
-	if err := windows.ReadFile(fd, buf, nil, &or); err != nil && err != windows.ERROR_IO_PENDING {
-		t.Fatal(err)
-	}
-	if err != nil {
-		t.Fatal(err)
-	}
-	if _, err := windows.WaitForSingleObject(or.HEvent, windows.INFINITE); err != nil {
-		t.Fatal(err)
-	}
-	if err := windows.GetOverlappedResult(fd, &or, &n, true); err != nil {
-		t.Fatal(err)
-	}
-	if string(buf) != string(content) {
-		t.Fatalf("got %q; want %q", buf, content)
-	}
-}