libmdbx Files

The supporting release of a stable branch with bug fixes. Recommended for use in production.

62 commits, 61 files changed, 3379 insertions(+), 676 deletions(-)

Important:

The project website libmdbx.dqdkfa.ru has been re-created:

• The advice, explanations, questions and answers, from correspondence, forums and other sources have been compiled.
• All information has been aggregated into a knowledge base, and the corresponding sections have been compiled on the website.
• The documentation generated via Doxgygen has been moved to /doxygen, with old links redirection.
• A lot of work has been done using AI.

Appreciations:

• Andrea Lanfranchi for bugs reporting and assistant fix ones.

Backward compatibility breaks:

• On Windows now stricter database placement checks on network, shared, and layered volumes to prevent database corruption and data loss. This can lead to a MDBX_EREMOTE error (ERROR_REMOTE_STORAGE_MEDIA_ERROR) return in dangerous situations when WOF is active (on compressed volumes). Just don't use Windows, let alone WOF, to avoid data loss, or open databases exclusively for reading only (MDBX_EXCLUSIVE | MDBX_RDONLY).

Improvements:

• The "crash" meaning clarified in the documentation.
• Prefer to use non-portable fallocate() to avoid emulation in glibc.
• More CI workflows: CLANG-ARM64 on Windows, MingGW both 32- and 64- bitness, etc.
• Refined mdbx_get_sysraminfo() internals for better avail_pages estimation.
• Clarified mdbx_env_defrag() to eliminate doubts about the non‑impact of result=nullptr on the returned code.

Fixes:

• Fixed entry point _except_handler4 not found in mdbx.dll in 32-bit build with MDBX_WITHOUT_MSVC_CRT=ON.
• Fixed building by CLANG/LLVM on Windows, including Microsoft Clang from Visual Studio.
• Fixed scan4seq_neon() for LLP4/ARM64-Windows.
• Fixed building for Win32 with MDBX_NATIVE_SEH=OFF without MASM, including cross-compilation cases.
• Fixed division truncation/underflow in the default_rp_augment_limit() which lead to too low and "stepwise" default MDBX_opt_rp_augment_limit.
• Fixed regression leads returning MDBX_BAD_TXN instead of MDBX_OUSTED in particular cases.
• Fixed doxygen mis-reference to the mdbx_set_panic().
• Fixed missing sub-page header check inside page_check() what could be causing SIGSEGV during checking a corrupted database.

For more information please see ChangeLog.