From e626219c9e35b37dece1348f1349c40866871f4c Mon Sep 17 00:00:00 2001 From: Gabriel Schneider Date: Wed, 30 Sep 2026 17:22:57 -0300 Subject: fs.md says that in a > to a tag cut into several writes, those taken before a refused one stand A `>` to a tag that a client sends in several writes is checked a write at a time. When a later one is refused, the earlier accepted ones stay in the tag. Buffering the whole open to apply it or none would cost more than it saves, so fs.md now says what happens: each write stands on its own, and only the refused one changes nothing. A test covers a truncation, an accepted write, then a refused one. Co-Authored-By: Claude Opus 5.5 --- src/ninep/cols.zig | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'src') diff --git a/src/ninep/cols.zig b/src/ninep/cols.zig index 4e497545..a1fe9ecc 100644 --- a/src/ninep/cols.zig +++ b/src/ninep/cols.zig @@ -253,6 +253,18 @@ test "pane/new takes rows from a pane in another column before refusing ENOSPC" try testing.expect(moved); } +test "in a > cut into several tag writes, those taken before a refused one stand" { + const p = try th.withFile(testing.allocator, "x\n"); + defer p.deinit(); + const node = tree.Node.of(th.serialOf(p), .tag); + _ = th.call(p, .{ .tag = 1, .op = .setattr, .node = node, .truncate = true }); + const h = th.call(p, .{ .tag = 2, .op = .open, .node = node, .omode = 1 }).reply.handle; + try testing.expectEqual(tree.Status.ok, th.call(p, .{ .tag = 3, .op = .write, .node = node, .handle = h, .data = "Make" }).reply.status); + try testing.expectEqual(E.INVAL, th.call(p, .{ .tag = 4, .op = .write, .node = node, .handle = h, .data = " \x01" }).errno()); + _ = th.call(p, .{ .tag = 5, .op = .release, .node = node, .handle = h, .opened = true }); + try testing.expect(std.mem.endsWith(u8, th.rd(p, node, 0, 4096).bytes, "Make")); +} + test "exactly 4096 bytes written with echo's newline after a truncation fit every kind of tag" { const p = try th.withFile(testing.allocator, "x\n"); defer p.deinit(); -- cgit v1.3