Revert "Fix infinite loop in Reader.Limited"

This reverts commit 27aba2d776caf59bb6569934626af587fdba9c75.

I'd like to review this contribution more carefully, particularly with
the alternate implementation that is also open as a pull request
(#25109).

Reopens #25093
This commit is contained in:
Andrew Kelley 2025-10-07 14:33:54 -07:00
parent 2c0aa1c6f5
commit b824ca8494

View File

@ -28,11 +28,9 @@ pub fn init(reader: *Reader, limit: Limit, buffer: []u8) Limited {
fn stream(r: *Reader, w: *Writer, limit: Limit) Reader.StreamError!usize {
const l: *Limited = @fieldParentPtr("interface", r);
const combined_limit = limit.min(l.remaining);
if (combined_limit.nonzero()) {
const n = try l.unlimited.stream(w, combined_limit);
l.remaining = l.remaining.subtract(n).?;
return n;
} else return error.EndOfStream;
const n = try l.unlimited.stream(w, combined_limit);
l.remaining = l.remaining.subtract(n).?;
return n;
}
test stream {
@ -51,64 +49,6 @@ test stream {
try std.testing.expectEqualStrings("test", result_buf[0..streamed]);
}
test "readSliceAll from infinite source" {
const InfSource = struct {
reader: std.Io.Reader,
pub fn init(buffer: []u8) @This() {
return @This(){
.reader = .{
.vtable = &.{
.stream = streamA,
},
.buffer = buffer,
.seek = 0,
.end = 0,
},
};
}
fn streamA(io_reader: *std.Io.Reader, w: *std.Io.Writer, limit: std.Io.Limit) std.Io.Reader.StreamError!usize {
_ = io_reader;
std.debug.assert(limit.nonzero());
const n_bytes_remaining = limit.minInt(2);
for (0..n_bytes_remaining) |_| {
try w.writeByte('A');
}
return n_bytes_remaining;
}
};
// Exact size
{
var inf_buf: [10]u8 = undefined;
var inf_stream = InfSource.init(&inf_buf);
var limit_buf: [2]u8 = undefined;
var limited: std.Io.Reader.Limited = .init(&inf_stream.reader, .limited(2), &limit_buf);
const limited_reader = &limited.interface;
var out_buffer: [2]u8 = undefined;
try std.testing.expectEqual({}, limited_reader.readSliceAll(&out_buffer));
try std.testing.expectEqualStrings("AA", &out_buffer);
}
// Too large
{
var inf_buf: [10]u8 = undefined;
var inf_stream = InfSource.init(&inf_buf);
var limit_buf: [2]u8 = undefined;
var limited: std.Io.Reader.Limited = .init(&inf_stream.reader, .limited(2), &limit_buf);
const limited_reader = &limited.interface;
var out_buffer: [8]u8 = undefined;
try std.testing.expectError(error.EndOfStream, limited_reader.readSliceAll(&out_buffer));
}
}
fn discard(r: *Reader, limit: Limit) Reader.Error!usize {
const l: *Limited = @fieldParentPtr("interface", r);
const combined_limit = limit.min(l.remaining);