authorgravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2025-07-16 13:08:33-07:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2025-07-16 17:20:03-07:00
log73cfba4d0d0ed00de8f5fbb83257d703ba284d61
tree773197139a7de182bcaf05d923836ef6c1e6a5a9
parente7a639967e91c8408ae281a97966e3dd67dd5565

std.Io.Writer: fix writeStruct

1 files changed, 28 insertions(+), 4 deletions(-)

lib/std/Io/Writer.zig+28-4
...@@ -483,7 +483,7 @@ pub fn writeSplatAll(w: *Writer, data: [][]const u8, splat: usize) Error!void {...@@ -483,7 +483,7 @@ pub fn writeSplatAll(w: *Writer, data: [][]const u8, splat: usize) Error!void {
483483
484 // Deal with any left over splats484 // Deal with any left over splats
485 if (data.len != 0 and truncate < data[index].len * splat) {485 if (data.len != 0 and truncate < data[index].len * splat) {
486 std.debug.assert(index == data.len - 1);486 assert(index == data.len - 1);
487 var remaining_splat = splat;487 var remaining_splat = splat;
488 while (true) {488 while (true) {
489 remaining_splat -= truncate / data[index].len;489 remaining_splat -= truncate / data[index].len;
...@@ -840,11 +840,11 @@ pub inline fn writeStruct(w: *Writer, value: anytype, endian: std.builtin.Endian...@@ -840,11 +840,11 @@ pub inline fn writeStruct(w: *Writer, value: anytype, endian: std.builtin.Endian
840 .auto => @compileError("ill-defined memory layout"),840 .auto => @compileError("ill-defined memory layout"),
841 .@"extern" => {841 .@"extern" => {
842 if (native_endian == endian) {842 if (native_endian == endian) {
843 return w.writeStruct(value);843 return w.writeAll(@ptrCast((&value)[0..1]));
844 } else {844 } else {
845 var copy = value;845 var copy = value;
846 std.mem.byteSwapAllFields(@TypeOf(value), &copy);846 std.mem.byteSwapAllFields(@TypeOf(value), &copy);
847 return w.writeStruct(copy);847 return w.writeAll(@ptrCast((&copy)[0..1]));
848 }848 }
849 },849 },
850 .@"packed" => {850 .@"packed" => {
...@@ -2606,8 +2606,32 @@ test "allocating sendFile" {...@@ -2606,8 +2606,32 @@ test "allocating sendFile" {
2606 var file_reader = file_writer.moveToReader();2606 var file_reader = file_writer.moveToReader();
2607 try file_reader.seekTo(0);2607 try file_reader.seekTo(0);
26082608
2609 var allocating: std.io.Writer.Allocating = .init(std.testing.allocator);2609 var allocating: std.io.Writer.Allocating = .init(testing.allocator);
2610 defer allocating.deinit();2610 defer allocating.deinit();
26112611
2612 _ = try file_reader.interface.streamRemaining(&allocating.writer);2612 _ = try file_reader.interface.streamRemaining(&allocating.writer);
2613}2613}
2614
2615test writeStruct {
2616 var buffer: [16]u8 = undefined;
2617 const S = extern struct { a: u64, b: u32, c: u32 };
2618 const s: S = .{ .a = 1, .b = 2, .c = 3 };
2619 {
2620 var w: Writer = .fixed(&buffer);
2621 try w.writeStruct(s, .little);
2622 try testing.expectEqualSlices(u8, &.{
2623 1, 0, 0, 0, 0, 0, 0, 0, //
2624 2, 0, 0, 0, //
2625 3, 0, 0, 0, //
2626 }, &buffer);
2627 }
2628 {
2629 var w: Writer = .fixed(&buffer);
2630 try w.writeStruct(s, .big);
2631 try testing.expectEqualSlices(u8, &.{
2632 0, 0, 0, 0, 0, 0, 0, 1, //
2633 0, 0, 0, 2, //
2634 0, 0, 0, 3, //
2635 }, &buffer);
2636 }
2637}