syscall: fix Open param names

syscall.Open param names are confusing, mainly because what should be
named flag is named mode and what should be named mode is named perm.

The name perm is used as synonym for mode in other places, so keep
it as is. Rename mode to flag to match the real meaning of the
parameter. Also, rename path to name for consistency with other
usage of the same parameter.

Change-Id: Ideed09839d80c0383584c2268afbb6cc09ffda8c
Reviewed-on: https://go-review.googlesource.com/c/go/+/619276
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

2 files changed, 16 insertions, 16 deletions

diff --git a/src/syscall/syscall_windows.go b/src/syscall/syscall_windows.go
index 6f6f9e4bde..84d6550c16 100644
--- a/src/syscall/syscall_windows.go
+++ b/src/syscall/syscall_windows.go
@@ -341,16 +341,16 @@ func makeInheritSa() *SecurityAttributes {
 	return &sa
 }
 
-func Open(path string, mode int, perm uint32) (fd Handle, err error) {
-	if len(path) == 0 {
+func Open(name string, flag int, perm uint32) (fd Handle, err error) {
+	if len(name) == 0 {
 		return InvalidHandle, ERROR_FILE_NOT_FOUND
 	}
-	pathp, err := UTF16PtrFromString(path)
+	namep, err := UTF16PtrFromString(name)
 	if err != nil {
 		return InvalidHandle, err
 	}
 	var access uint32
-	switch mode & (O_RDONLY | O_WRONLY | O_RDWR) {
+	switch flag & (O_RDONLY | O_WRONLY | O_RDWR) {
 	case O_RDONLY:
 		access = GENERIC_READ
 	case O_WRONLY:
@@ -358,16 +358,16 @@ func Open(path string, mode int, perm uint32) (fd Handle, err error) {
 	case O_RDWR:
 		access = GENERIC_READ | GENERIC_WRITE
 	}
-	if mode&O_CREAT != 0 {
+	if flag&O_CREAT != 0 {
 		access |= GENERIC_WRITE
 	}
-	if mode&O_APPEND != 0 {
+	if flag&O_APPEND != 0 {
 		access &^= GENERIC_WRITE
 		access |= FILE_APPEND_DATA
 	}
 	sharemode := uint32(FILE_SHARE_READ | FILE_SHARE_WRITE)
 	var sa *SecurityAttributes
-	if mode&O_CLOEXEC == 0 {
+	if flag&O_CLOEXEC == 0 {
 		sa = makeInheritSa()
 	}
 	// We don't use CREATE_ALWAYS, because when opening a file with
@@ -377,9 +377,9 @@ func Open(path string, mode int, perm uint32) (fd Handle, err error) {
 	// Instead, we ftruncate the file after opening when O_TRUNC is set.
 	var createmode uint32
 	switch {
-	case mode&(O_CREAT|O_EXCL) == (O_CREAT | O_EXCL):
+	case flag&(O_CREAT|O_EXCL) == (O_CREAT | O_EXCL):
 		createmode = CREATE_NEW
-	case mode&O_CREAT == O_CREAT:
+	case flag&O_CREAT == O_CREAT:
 		createmode = OPEN_ALWAYS
 	default:
 		createmode = OPEN_EXISTING
@@ -392,22 +392,22 @@ func Open(path string, mode int, perm uint32) (fd Handle, err error) {
 		// Necessary for opening directory handles.
 		attrs |= FILE_FLAG_BACKUP_SEMANTICS
 	}
-	if mode&O_SYNC != 0 {
+	if flag&O_SYNC != 0 {
 		const _FILE_FLAG_WRITE_THROUGH = 0x80000000
 		attrs |= _FILE_FLAG_WRITE_THROUGH
 	}
-	h, err := CreateFile(pathp, access, sharemode, sa, createmode, attrs, 0)
+	h, err := CreateFile(namep, access, sharemode, sa, createmode, attrs, 0)
 	if err != nil {
-		if err == ERROR_ACCESS_DENIED && (mode&O_WRONLY != 0 || mode&O_RDWR != 0) {
+		if err == ERROR_ACCESS_DENIED && (flag&O_WRONLY != 0 || flag&O_RDWR != 0) {
 			// We should return EISDIR when we are trying to open a directory with write access.
-			fa, e1 := GetFileAttributes(pathp)
+			fa, e1 := GetFileAttributes(namep)
 			if e1 == nil && fa&FILE_ATTRIBUTE_DIRECTORY != 0 {
 				err = EISDIR
 			}
 		}
 		return InvalidHandle, err
 	}
-	if mode&O_TRUNC == O_TRUNC {
+	if flag&O_TRUNC == O_TRUNC {
 		err = Ftruncate(h, 0)
 		if err != nil {
 			CloseHandle(h)
diff --git a/src/syscall/syscall_windows_test.go b/src/syscall/syscall_windows_test.go
index 9773cfbfa2..03821ea594 100644
--- a/src/syscall/syscall_windows_test.go
+++ b/src/syscall/syscall_windows_test.go
@@ -20,7 +20,7 @@ func TestOpen_Dir(t *testing.T) {
 
 	dir := t.TempDir()
 	tests := []struct {
-		mode int
+		flag int
 		err  error
 	}{
 		{syscall.O_RDONLY, nil},
@@ -32,7 +32,7 @@ func TestOpen_Dir(t *testing.T) {
 		{syscall.O_RDWR, syscall.EISDIR},
 	}
 	for i, tt := range tests {
-		h, err := syscall.Open(dir, tt.mode, 0)
+		h, err := syscall.Open(dir, tt.flag, 0)
 		if err == nil {
 			syscall.CloseHandle(h)
 		}