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Fix mapped input dangling - #429
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ucl_parser_add_fd_full and ucl_parser_add_file_full mmap the input, parse it, then munmap it. Two things still point into the mapping afterwards. Zero-copy objects: with UCL_PARSER_ZEROCOPY, keys and string values are pointers into the input, so after a successful ucl_parser_add_fd a lookup reads unmapped memory. The flag documents zero-copy 'if possible', and for a file it never is, because the library releases the buffer itself. The chunk: it stays in parser->chunks with pos/end into the mapping, so after a parse error ucl_parser_chunk_peek and ucl_parser_chunk_skip dereference it. Add a helper used by both: parse with UCL_PARSER_ZEROCOPY temporarily cleared, unmap, and clear begin/pos/end/remain of the chunk that referred to it - chunk_peek and chunk_skip already treat a NULL pos as no data. Zero-copy for ucl_parser_add_chunk*, where the caller owns the memory, is unchanged. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01W3aXdPKAnVwjiNtZstnmPj
vstakhov
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Oct 7, 2026
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LGTM. Reproduced both cases from the issue on master under ASan: the zerocopy lookup after ucl_parser_add_fd(), and chunk peek/skip after a failed parse. Both are clean on this branch.
Non-blocking follow-up: .include (ucl_include_file_single) has the same pattern. It mmaps, parses with the caller's UCL_PARSER_ZEROCOPY, then munmaps. So zerocopy + .include from caller-owned input still leaves keys dangling, and a failed include leaves a chunk pointing into the unmapped file.
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Fix #428