src/buffer/Buffer.zig

@@ -1610,37 +1610,14 @@ pub fn store_to_existing_file_const(self: *const Self, file_path_: []const u8) S
         file_path = link;
     }
 
-    var write_buffer: [4096]u8 = undefined;
-
-    if (builtin.os.tag == .windows) {
-        // windows uses ACLs for ownership so we preserve mode only
     var atomic = blk: {
+        var write_buffer: [4096]u8 = undefined;
         const stat = cwd().statFile(file_path) catch
             break :blk try cwd().atomicFile(file_path, .{ .write_buffer = &write_buffer });
         break :blk try cwd().atomicFile(file_path, .{ .mode = stat.mode, .write_buffer = &write_buffer });
     };
     defer atomic.deinit();
     try self.store_to_file_const(&atomic.file_writer.interface);
-        return atomic.finish();
-    }
-
-    // use fstat to get uid/gid, which std.fs.File.Stat omits.
-    const orig_stat: ?std.posix.Stat = blk: {
-        const f = cwd().openFile(file_path, .{}) catch break :blk null;
-        defer f.close();
-        break :blk std.posix.fstat(f.handle) catch null;
-    };
-    const mode: std.fs.File.Mode = if (orig_stat) |s| s.mode else std.fs.File.default_mode;
-    var atomic = try cwd().atomicFile(file_path, .{ .mode = mode, .write_buffer = &write_buffer });
-    defer atomic.deinit();
-    try self.store_to_file_const(&atomic.file_writer.interface);
-    // fchmod bypasses the process umask preserving the exact original mode
-    // fchown restores original owner/group
-    // EPERM is silently ignored when we lack sufficient privileges
-    if (orig_stat) |s| {
-        atomic.file_writer.file.chmod(s.mode) catch {};
-        std.posix.fchown(atomic.file_writer.file.handle, s.uid, s.gid) catch {};
-    }
     try atomic.finish();
 }
 

test/tests_buffer.zig

@@ -1,5 +1,4 @@
 const std = @import("std");
-const builtin = @import("builtin");
 const Buffer = @import("Buffer");
 
 const ArrayList = std.ArrayList;
@@ -100,39 +99,6 @@ test "buffer.store_to_file_and_clean" {
     try std.testing.expectEqualStrings(input, output);
 }
 
-test "buffer.store_to_file_and_clean preserves file mode" {
-    if (comptime builtin.os.tag == .windows) return error.SkipZigTest;
-
-    const tmp_path = "test/tmp_mode_test.txt";
-    {
-        const f = try std.fs.cwd().createFile(tmp_path, .{});
-        defer f.close();
-        try f.writeAll("hello\n");
-        try f.chmod(0o644);
-    }
-    defer std.fs.cwd().deleteFile(tmp_path) catch {};
-
-    // Set a umask that would strip group/other read bits (0o644 -> 0o600 without the fix)
-    // to verify that fchmod bypasses the process umask on save.
-    const prev_umask = if (comptime builtin.os.tag == .linux)
-        std.os.linux.syscall1(.umask, 0o077)
-    else
-        @as(usize, 0);
-    defer if (comptime builtin.os.tag == .linux) {
-        _ = std.os.linux.syscall1(.umask, prev_umask);
-    };
-
-    const buffer = try Buffer.create(a);
-    defer buffer.deinit();
-    try buffer.load_from_file_and_update(tmp_path);
-    try buffer.store_to_file_and_clean(tmp_path);
-
-    const f = try std.fs.cwd().openFile(tmp_path, .{});
-    defer f.close();
-    const stat = try std.posix.fstat(f.handle);
-    try std.testing.expectEqual(@as(std.posix.mode_t, 0o644), stat.mode & 0o777);
-}
-
 fn get_line(buf: *const Buffer, line: usize) ![]const u8 {
     var result: std.Io.Writer.Allocating = .init(a);
     try buf.root.get_line(line, &result.writer, metrics());