Namespace-wrap vendored mbedtls to avoid clashes with statically-linked duckdb - #830
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Both ladybug's third_party/mbedtls and a statically-linked duckdb (libduckdb_static.a) bundle mbedtls with plain, unprefixed mbedtls_* symbols. When both end up on one link line (e.g. GEN=Ninja make shell EXTENSION_STATIC_LINK_LIST='httpfs'), the linker reports ~19 duplicate symbol errors for _mbedtls_cipher_*. Fix by wrapping our vendored copy in namespace lbug_mbedtls: - third_party/ports/mbedtls/do-patch.py (new): port patch script, following the zstd port pattern. It renames .c -> .cpp, strips the now-dead extern "C" guards (the copy is compiled as C++ everywhere), and wraps top-level code segments in balanced namespace pairs. Segmentation tracks preprocessor conditional context and brace depth per line, so sibling conditional branches (MBEDTLS_AES_ALT vs MBEDTLS_SELF_TEST) and mid-declaration conditionals (lone 'static' followed by a conditional attribute block) stay balanced. It also absorbs the previously-missing format_c_to_cpp.py step, making the port runnable again. - ports/mbedtls/Makefile: invoke do-patch.py during build. - third_party/mbedtls: vendored sources regenerated via the script (57 files; only namespace pairs and extern "C" removals). Public headers re-expose names via 'using namespace lbug_mbedtls', so in-tree consumers (src/common/sha256.cpp, extension/httpfs/src/crypto.cpp) are unchanged. Requires LadybugDB/extensions#63 (submodule bump included here). Verified with GEN=Ninja make shell EXTENSION_STATIC_LINK_LIST='httpfs': the link succeeds, libmbedtls.a exports zero plain _mbedtls_* symbols, and the shell passes a smoke query.
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Problem
GEN=Ninja make shell EXTENSION_STATIC_LINK_LIST='httpfs'failed at the final link with duplicate symbol errors: both ourthird_party/mbedtlsand Homebrew'slibduckdb_static.abundle mbedtls with plain, unprefixedmbedtls_*symbols, and both copies get pulled into the shell link.Fix
Wrap our vendored mbedtls in
namespace lbug_mbedtlsso its symbols can never collide with another statically-linked mbedtls copy:.c->.cpp, strips the deadextern "C"guards (the copy is compiled as C++ everywhere, and C linkage is exactly what forces plain symbol names), and wraps top-level code segments in balancednamespace lbug_mbedtls { }pairs. Segmentation tracks preprocessor conditional context and brace depth per line, so sibling conditional branches (MBEDTLS_AES_ALTvsMBEDTLS_SELF_TEST) and mid-declaration conditionals (the lonestatic+ conditional-attribute idiom inbignum.cpp) stay balanced. Also absorbs the previously-missingformat_c_to_cpp.pystep, making the port runnable again.do-patch.pyduring build.extern "C"removals).libduckdb_generated_extension_loader.a+ bundled extension archives when linking duckdb statically).Public headers re-expose names via
using namespace lbug_mbedtls, so in-tree consumers (src/common/sha256.cpp,extension/httpfs/src/crypto.cpp) are unchanged.Verification
GEN=Ninja make shell EXTENSION_STATIC_LINK_LIST='httpfs'completes: the link succeeds,libmbedtls.aexports zero plain_mbedtls_*symbols (222 namespaced ones), and the shell passes a smoke query.