fix: cap HTTP response buffer at 512 KB to prevent OOM on Pi#110
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writeCallback had no size limit, so a runaway API response (large error HTML, misconfigured proxy, etc.) could exhaust memory on a Pi with limited RAM. Adding a 512 KB hard cap — normal weatherapi.com responses are ~10 KB — and returning 0 from the callback to abort the transfer with CURLE_WRITE_ERROR, which the existing error-handling path already treats as a failed fetch. https://claude.ai/code/session_0166Zd59EUgWgYd3FrphQAio
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Summary
writeCallbackinweather.cppaccumulated the full API response into an unboundedstd::string. A broken server, misconfigured proxy, or network middlebox returning a large HTML error page could silently exhaust the Pi's limited RAM.The fix adds a 512 KB hard cap. Normal weatherapi.com responses are ~10 KB, so this gives more than 50× headroom before aborting. Returning
0from the libcurl write callback causes libcurl to abort withCURLE_WRITE_ERROR, which the existing error path already handles as a failed fetch — no other code changes needed.Changes
src/weather.cpp: addMAX_RESPONSE_BYTES = 512 KBconstant; check cumulative buffer size on every write; return 0 to abort and log an error if exceededTest plan