fix(agent/reconnectingpty): read reconnecting-PTY init with io.ReadFull#26538
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fix(agent/reconnectingpty): read reconnecting-PTY init with io.ReadFull#26538yuriy-at-persona wants to merge 1 commit into
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handleConn read the length-prefixed AgentReconnectingPTYInit with single conn.Read calls. A single Read on a network connection can return fewer bytes than requested, so when the init spans multiple segments the body is read short and left NUL-padded, json.Unmarshal fails with "failed to unmarshal init", and the agent returns without starting the PTY. The session then connects but delivers no output, intermittently. Read both the length prefix and the body with io.ReadFull, matching the length-prefixed framing read in agent/boundarylogproxy/codec. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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handleConnreads the length-prefixedAgentReconnectingPTYInitwith a singleconn.Readfor the 2-byte length and another for the body. A singleReadon a network connection can return fewer bytes than requested, so when the init spans multiple segments (more likely with a largerCommand) the body is read short and left NUL-padded,json.Unmarshalfails withfailed to unmarshal init, and the agent returns without starting the reconnecting PTY. The session then connects but delivers no output, intermittently.Read both the length prefix and the body with
io.ReadFull, matching the length-prefixed framing read inagent/boundarylogproxy/codec.Note: the length prefix is a
uint16, so an init larger than 64 KiB would still wrap; that is a separate pre-existing issue and is not addressed here.