karlseguin.tngl.sh
A websocket implementation for zig
client: skip poll when TLS plaintext is buffered; surface poll errors
Addresses review: a prior read can decrypt more than the caller consumed, leaving
plaintext in the TLS client's buffer while the socket is empty, so polling the fd
would spuriously time out and starve buffered data. Check reader.bufferedLen()
first. A poll failure is surfaced as a read failure (mapped into the fill error
set) rather than swallowed.
author
Kyle 🐆
date
(Jun 18, 2026, 8:25 PM -0400)
commit
443c38ca
443c38ca4777548fb5dd97e6c5b6a760c2c74a36
parent
ae78dced
ae78dced086d70f6f09496e1b0f08ff7e201885f
+11
-4
+11
-4
src/client/client.zig
+11
-4
src/client/client.zig
···
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// SO_RCVTIMEO produces on timeout) as a programmer bug and panics in
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// debug builds. Polling lets a timeout surface as error.WouldBlock (which
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// read() turns into "no message") without ever issuing a read that could
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// EAGAIN. The caller drains its buffer before reaching here, so polling
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// only gates an actual socket read.
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if (self.read_timeout_ms > 0) {
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// EAGAIN.
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//
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// Skip the poll when the TLS client already has decrypted plaintext
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// buffered: a previous read can decrypt more than the caller consumed, so
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// the socket can be empty (poll would time out) even though data is
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// available in-process, which would starve it.
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const tls_buffered = if (self.tls_client) |tls_client| tls_client.client.reader.bufferedLen() else 0;
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if (self.read_timeout_ms > 0 and tls_buffered == 0) {
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var pfd = [_]std.posix.pollfd{.{
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.fd = self.stream.socket.handle,
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.events = std.posix.POLL.IN,
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.revents = 0,
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}};
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const ready = std.posix.poll(&pfd, @intCast(self.read_timeout_ms)) catch 0;
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// A poll failure is a real read failure, not "no data": surface it
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// (mapped into this read path's error set) rather than swallowing it.
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const ready = std.posix.poll(&pfd, @intCast(self.read_timeout_ms)) catch return error.ReadFailed;
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if (ready == 0) return error.WouldBlock;
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}
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if (self.tls_client) |tls_client| {