std.windows: use atomic rename, if possible

Mitigates ziglang#14978.
matu3ba · Aug 21, 2023 · 6d5fdd2 · 6d5fdd2
1 parent 6a54639
commit 6d5fdd2
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Showing 2 changed files with 48 additions and 14 deletions.
diff --git a/lib/std/os.zig b/lib/std/os.zig
@@ -2636,23 +2636,44 @@ pub fn renameatW(
 
     const rename_info = @as(*windows.FILE_RENAME_INFORMATION, @ptrCast(&rename_info_buf));
 
-    rename_info.* = .{
-        .ReplaceIfExists = ReplaceIfExists,
-        .RootDirectory = if (std.fs.path.isAbsoluteWindowsWTF16(new_path_w)) null else new_dir_fd,
-        .FileNameLength = @as(u32, @intCast(new_path_w.len * 2)), // already checked error.NameTooLong
-        .FileName = undefined,
-    };
+    if (builtin.target.os.version_range.windows.min.isAtLeast(.win10_rs1)) {
+        var flags: windows.ULONG = windows.FILE_RENAME_POSIX_SEMANTICS | windows.FILE_RENAME_IGNORE_READONLY_ATTRIBUTE;
+        if (ReplaceIfExists == windows.TRUE) flags |= windows.FILE_RENAME_REPLACE_IF_EXISTS;
+        rename_info.* = .{
+            .Flags = flags,
+            .RootDirectory = if (std.fs.path.isAbsoluteWindowsWTF16(new_path_w)) null else new_dir_fd,
+            .FileNameLength = @intCast(new_path_w.len * 2), // already checked error.NameTooLong
+            .FileName = undefined,
+        };
+    } else {
+        rename_info.* = .{
+            .Flags = ReplaceIfExists,
+            .RootDirectory = if (std.fs.path.isAbsoluteWindowsWTF16(new_path_w)) null else new_dir_fd,
+            .FileNameLength = @intCast(new_path_w.len * 2), // already checked error.NameTooLong
+            .FileName = undefined,
+        };
+    }
     @memcpy(@as([*]u16, &rename_info.FileName)[0..new_path_w.len], new_path_w);
 
     var io_status_block: windows.IO_STATUS_BLOCK = undefined;
 
-    const rc = windows.ntdll.NtSetInformationFile(
-        src_fd,
-        &io_status_block,
-        rename_info,
-        @as(u32, @intCast(struct_len)), // already checked for error.NameTooLong
-        .FileRenameInformation,
-    );
+    const rc = if (comptime builtin.target.os.version_range.windows.min.isAtLeast(.win10_rs1)) {
+        windows.ntdll.NtSetInformationFile(
+            src_fd,
+            &io_status_block,
+            rename_info,
+            @intCast(struct_len), // already checked for error.NameTooLong
+            .FileRenameInformationEx,
+        );
+    } else {
+        windows.ntdll.NtSetInformationFile(
+            src_fd,
+            &io_status_block,
+            rename_info,
+            @intCast(struct_len), // already checked for error.NameTooLong
+            .FileRenameInformation,
+        );
+    };
 
     switch (rc) {
         .SUCCESS => return,

diff --git a/lib/std/os/windows.zig b/lib/std/os/windows.zig
@@ -2856,8 +2856,21 @@ const FILE_DISPOSITION_FORCE_IMAGE_SECTION_CHECK: ULONG = 0x00000004;
 const FILE_DISPOSITION_ON_CLOSE: ULONG = 0x00000008;
 const FILE_DISPOSITION_IGNORE_READONLY_ATTRIBUTE: ULONG = 0x00000010;
 
+// FILE_RENAME_INFORMATION.Flags
+pub const FILE_RENAME_REPLACE_IF_EXISTS = 0x00000001;
+pub const FILE_RENAME_POSIX_SEMANTICS = 0x00000002;
+pub const FILE_RENAME_SUPPRESS_PIN_STATE_INHERITANCE = 0x00000004;
+pub const FILE_RENAME_SUPPRESS_STORAGE_RESERVE_INHERITANCE = 0x00000008;
+pub const FILE_RENAME_NO_INCREASE_AVAILABLE_SPACE = 0x00000010;
+pub const FILE_RENAME_NO_DECREASE_AVAILABLE_SPACE = 0x00000020;
+pub const FILE_RENAME_PRESERVE_AVAILABLE_SPACE = 0x00000030;
+pub const FILE_RENAME_IGNORE_READONLY_ATTRIBUTE = 0x00000040;
+pub const FILE_RENAME_FORCE_RESIZE_TARGET_SR = 0x00000080;
+pub const FILE_RENAME_FORCE_RESIZE_SOURCE_SR = 0x00000100;
+pub const FILE_RENAME_FORCE_RESIZE_SR = 0x00000180;
+
 pub const FILE_RENAME_INFORMATION = extern struct {
-    ReplaceIfExists: BOOLEAN,
+    Flags: if (builtin.target.os.version_range.windows.min.isAtLeast(.win10_rs1)) ULONG else BOOLEAN,
     RootDirectory: ?HANDLE,
     FileNameLength: ULONG,
     FileName: [1]WCHAR,