internal/syscall/windows: increase internal Windows O_ flags values

The lowercase o_ flags are invented values. These conflict with
constants that will soon be allowed by os.OpenFile, which values will
be mandated by the Windows API. To avoid this overlap, the internal
values have been increased to the 33-63 bit range, as the Windows ones
are in the 0-32 bit range.

Updates #73676

Change-Id: I0f657f3ed3403de150f1730a5a65ae887a18a4e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/697363
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

diff --git a/src/internal/syscall/windows/at_windows.go b/src/internal/syscall/windows/at_windows.go
index d48fce1c99dc3673b18da2bca542e1dbf06008b0..8b19a03e7e240cb36047bc1e6838fecb26e1d9e5 100644 (file)
--- a/src/internal/syscall/windows/at_windows.go
+++ b/src/internal/syscall/windows/at_windows.go
@@ -13,16 +13,17 @@ import (
 
 // Openat flags not supported by syscall.Open.
 //
-// These are invented values.
+// These are invented values, use values in the 33-63 bit range
+// to avoid overlap with flags and attributes supported by [syscall.Open].
 //
 // When adding a new flag here, add an unexported version to
 // the set of invented O_ values in syscall/types_windows.go
 // to avoid overlap.
 const (
-       O_DIRECTORY    = 0x100000   // target must be a directory
-       O_NOFOLLOW_ANY = 0x20000000 // disallow symlinks anywhere in the path
-       O_OPEN_REPARSE = 0x40000000 // FILE_OPEN_REPARSE_POINT, used by Lstat
-       O_WRITE_ATTRS  = 0x80000000 // FILE_WRITE_ATTRIBUTES, used by Chmod
+       O_DIRECTORY    = 0x100000000 // target must be a directory
+       O_NOFOLLOW_ANY = 0x200000000 // disallow symlinks anywhere in the path
+       O_OPEN_REPARSE = 0x400000000 // FILE_OPEN_REPARSE_POINT, used by Lstat
+       O_WRITE_ATTRS  = 0x800000000 // FILE_WRITE_ATTRIBUTES, used by Chmod
 )
 
 func Openat(dirfd syscall.Handle, name string, flag uint64, perm uint32) (_ syscall.Handle, e1 error) {

diff --git a/src/os/root_windows.go b/src/os/root_windows.go
index 523ee48d13f8c00fae97e60ac2b1cb1bd465af4b..afc645d8f88822b3e0bf4dd7beaa833b62ba7983 100644 (file)
--- a/src/os/root_windows.go
+++ b/src/os/root_windows.go
@@ -129,7 +129,7 @@ func openRootInRoot(r *Root, name string) (*Root, error) {
 // rootOpenFileNolog is Root.OpenFile.
 func rootOpenFileNolog(root *Root, name string, flag int, perm FileMode) (*File, error) {
        fd, err := doInRoot(root, name, nil, func(parent syscall.Handle, name string) (syscall.Handle, error) {
-               return openat(parent, name, flag, perm)
+               return openat(parent, name, uint64(flag), perm)
        })
        if err != nil {
                return nil, &PathError{Op: "openat", Path: name, Err: err}
@@ -138,8 +138,8 @@ func rootOpenFileNolog(root *Root, name string, flag int, perm FileMode) (*File,
        return newFile(fd, joinPath(root.Name(), name), "file", false), nil
 }
 
-func openat(dirfd syscall.Handle, name string, flag int, perm FileMode) (syscall.Handle, error) {
-       h, err := windows.Openat(dirfd, name, uint64(flag)|syscall.O_CLOEXEC|windows.O_NOFOLLOW_ANY, syscallMode(perm))
+func openat(dirfd syscall.Handle, name string, flag uint64, perm FileMode) (syscall.Handle, error) {
+       h, err := windows.Openat(dirfd, name, flag|syscall.O_CLOEXEC|windows.O_NOFOLLOW_ANY, syscallMode(perm))
        if err == syscall.ELOOP || err == syscall.ENOTDIR {
                if link, err := readReparseLinkAt(dirfd, name); err == nil {
                        return syscall.InvalidHandle, errSymlink(link)

diff --git a/src/syscall/types_windows.go b/src/syscall/types_windows.go
index 92fa796a80eed7007e08b1ac38453543e009ce34..dd21fc83294af76fe8c4d1466c150953c957811c 100644 (file)
--- a/src/syscall/types_windows.go
+++ b/src/syscall/types_windows.go
@@ -48,10 +48,10 @@ const (
        O_SYNC         = 0x01000
        O_ASYNC        = 0x02000
        O_CLOEXEC      = 0x80000
-       o_DIRECTORY    = 0x100000   // used by internal/syscall/windows
-       o_NOFOLLOW_ANY = 0x20000000 // used by internal/syscall/windows
-       o_OPEN_REPARSE = 0x40000000 // used by internal/syscall/windows
-       o_WRITE_ATTRS  = 0x80000000 // used by internal/syscall/windows
+       o_DIRECTORY    = 0x100000000 // used by internal/syscall/windows
+       o_NOFOLLOW_ANY = 0x200000000 // used by internal/syscall/windows
+       o_OPEN_REPARSE = 0x400000000 // used by internal/syscall/windows
+       o_WRITE_ATTRS  = 0x800000000 // used by internal/syscall/windows
 )
 
 const (