mdbx: release v0.11.2

Acknowledgements:
-----------------

 - [장세연 (Чан Се Ен)](https://github.com/sasgas) for contributing to C++ API.
 - [Alain Picard](https://github.com/castortech) for [Java bindings](https://github.com/castortech/mdbxjni).
 - [Alex Sharov](https://github.com/AskAlexSharov) for reporting and testing.
 - [Kris Zyp](https://github.com/kriszyp) for reporting and testing.
 - [Artem Vorotnikov](https://github.com/vorot93) for support [Rust wrapper](https://github.com/vorot93/libmdbx-rs).

Fixes:
------

 - [Fixed compilation](https://github.com/erthink/libmdbx/pull/239) with `devtoolset-9` on CentOS/RHEL 7.
 - [Fixed unexpected `MDBX_PROBLEM` error](https://github.com/erthink/libmdbx/issues/242) because of update an obsolete meta-page.
 - [Fixed returning `MDBX_NOTFOUND` error](https://github.com/erthink/libmdbx/issues/243) in case an inexact value found for `MDBX_GET_BOTH` operation.
 - [Fixed compilation](https://github.com/erthink/libmdbx/issues/245) without kernel/libc-devel headers.

Minors:
-------

 - Fixed `constexpr`-related macros for legacy compilers.
 - Allowed to define 'CMAKE_CXX_STANDARD` using an environment variable.
 - Simplified collection statistics of page operation .
 - Added `MDBX_FORCE_BUILD_AS_MAIN_PROJECT` cmake option.
 - Remove unneeded `#undef P_DIRTY`.

Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>

.github/FUNDING.yml

@@ -9,4 +9,4 @@ community_bridge: # Replace with a single Community Bridge project-name e.g., cl
 liberapay: # Replace with a single Liberapay username
 issuehunt: # Replace with a single IssueHunt username
 otechie: # Replace with a single Otechie username
-custom: ['https://sobe.ru/na/libmdbx', 'https://paypal.me/erthink', 'https://etherscan.io/address/0x19291d8658f762f3baceae1700c0b9466572ceab']
+custom: ['https://sobe.ru/na/libmdbx', 'https://paypal.me/erthink', 'https://www.blockchain.com/en/eth/address/0x19291d8658f762f3baceae1700c0b9466572ceab', 'https://www.blockchain.com/en/btc/address/152u2KXNWWGHQS3qiBEoQaveWyPvaSWYGC']

.github/actions/spelling/expect.txt

@@ -68,6 +68,7 @@ asprintf
 aspx
 assection
 AstraLinux
+astralinux
 atal
 atexit
 atfork
@@ -99,6 +100,7 @@ bfin
 biarch
 bibtex
 BIGDATA
+bigdata
 bindir
 binfmt
 binutils
@@ -600,6 +602,7 @@ github
 githubusercontent
 gitignore
 glibc
+GLIBCXX
 globals
 gmail
 gmake
@@ -709,6 +712,7 @@ inprocess
 INSTEADOF
 integerdup
 integerkey
+interoperability
 interprocedural
 intlimits
 intptr
@@ -978,6 +982,7 @@ microsoft
 Mikkelson
 minflt
 MINGW
+mingw
 minimalistic
 minkeys
 minlen
@@ -1276,6 +1281,7 @@ pmax
 pmccntr
 pmcntenset
 pmedvedev
+pmeta
 pmr
 pmuseren
 pmwkaa
@@ -1315,6 +1321,7 @@ proba
 proces
 procfs
 progname
+programdata
 PROGRAMLISTING
 projectbrief
 projectlogo
@@ -1403,11 +1410,13 @@ REALMEM
 REALPATH
 realtime
 Rebuffo
+rebuffo
 RECO
 redis
 reedom
 reefont
 refname
+refreshenv
 REGEX
 regexp
 reinited

.github/workflows/MinGW.yml

@@ -27,38 +27,39 @@ jobs:
     - uses: actions/checkout@v2
     - name: fetch tags
       run: git fetch --unshallow --tags --prune --force
+    - name: append PATH
+      run: echo 'C:/ProgramData/chocolatey/lib/mingw/tools/install/mingw64/bin' >> $GITHUB_PATH
     - name: update mingw64
       # wanna version >= 10.2
-      run: choco upgrade mingw -y --no-progress
+      run: choco upgrade mingw -y --no-progress && refreshenv
     - name: configure-dll
-      run: mkdir build-dll && cd build-dll && cmake  -G "MinGW Makefiles" -DMDBX_BUILD_SHARED_LIBRARY:BOOL=ON -DMDBX_INSTALL_STATIC:BOOL=OFF ..
+      shell: bash
+      run: |
+        mkdir build-dll && cd build-dll && \
+        cmake -G "MinGW Makefiles" -DMDBX_BUILD_SHARED_LIBRARY:BOOL=ON -DMDBX_INSTALL_STATIC:BOOL=OFF -DMDBX_ENABLE_TESTS:BOOL=ON ..
     - name: build-dll
+      shell: bash
       run: cd build-dll && cmake --build .
     - name: test-dll
-      shell: pwsh
+      shell: bash
       run: |
-        cd build-dll
-        ls
-        ./mdbx_test --progress --console=no --pathname=test.db --dont-cleanup-after basic > test.log
-        Get-Content test.log | Select-Object -last 42
-        if ($LastExitCode -ne 0) {
-            throw "Exec: $ErrorMessage"
-        } else {
-            ./mdbx_chk -nvv test.db | Tee-Object -file chk.log | Select-Object -last 42
-        }
+        export "PATH=/c/programdata/chocolatey/lib/mingw/tools/install/mingw64/bin:$PATH" && \
+        cd build-dll && \
+        ./mdbx_test.exe --progress --console=no --pathname=test.db --dont-cleanup-after basic && \
+        ./mdbx_chk.exe -nvv test.db
     - name: configure-static
-      run: mkdir build-static && cd build-static && cmake  -G "MinGW Makefiles" -DMDBX_BUILD_SHARED_LIBRARY:BOOL=OFF -DMDBX_INSTALL_STATIC:BOOL=ON ..
-    - name: build-static
-      run: cd build-static && cmake --build .
-    - name: test-static
-      shell: pwsh
+      shell: bash
       run: |
-        cd build-static
-        ls
-        ./mdbx_test --progress --console=no --pathname=test.db --dont-cleanup-after basic > test.log
-        Get-Content test.log | Select-Object -last 42
-        if ($LastExitCode -ne 0) {
-            throw "Exec: $ErrorMessage"
-        } else {
-            ./mdbx_chk -nvv test.db | Tee-Object -file chk.log | Select-Object -last 42
-        }
+        mkdir build-static && cd build-static && \
+        cmake -G "MinGW Makefiles" -DMDBX_BUILD_SHARED_LIBRARY:BOOL=OFF -DMDBX_INSTALL_STATIC:BOOL=ON -DMDBX_ENABLE_TESTS:BOOL=ON ..
+    - name: build-static
+      shell: bash
+      run: |
+        cd build-static && cmake --build .
+    - name: test-static
+      shell: bash
+      run: |
+        export "PATH=/c/programdata/chocolatey/lib/mingw/tools/install/mingw64/bin:$PATH" && \
+        cd build-static && \
+        ./mdbx_test.exe --progress --console=no --pathname=test.db --dont-cleanup-after basic && \
+        ./mdbx_chk.exe -nvv test.db

CMakeLists.txt

@@ -93,6 +93,10 @@ else()
 endif()
 
 if(DEFINED PROJECT_NAME)
+  option(MDBX_FORCE_BUILD_AS_MAIN_PROJECT "Force libmdbx to full control build options even it added as a subdirectory to your project." OFF)
+endif()
+
+if(DEFINED PROJECT_NAME AND NOT MDBX_FORCE_BUILD_AS_MAIN_PROJECT)
   set(SUBPROJECT ON)
   set(NOT_SUBPROJECT OFF)
   if(NOT MDBX_AMALGAMATED_SOURCE AND NOT DEFINED BUILD_TESTING)
@@ -294,11 +298,11 @@ else()
 
     if(UNIX)
       find_program(CLANG_FORMAT
-        NAMES clang-format-12 clang-format-11 clang-format-10 clang-format)
+        NAMES clang-format-13 clang-format)
       if(CLANG_FORMAT)
         execute_process(COMMAND ${CLANG_FORMAT} "--version" OUTPUT_VARIABLE clang_format_version_info)
         string(REGEX MATCH "version ([0-9]+)\\.([0-9]+)\\.([0-9]+)(.*)?" clang_format_version_info CLANG_FORMAT_VERSION)
-        if(clang_format_version_info AND NOT CLANG_FORMAT_VERSION VERSION_LESS 10.0)
+        if(clang_format_version_info AND NOT CLANG_FORMAT_VERSION VERSION_LESS 13.0)
           # Enable 'make reformat' target.
           add_custom_target(reformat
             VERBATIM
@@ -334,9 +338,16 @@ list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_11 HAS_CXX11)
 list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_14 HAS_CXX14)
 list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_17 HAS_CXX17)
 list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_20 HAS_CXX20)
+list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_23 HAS_CXX23)
 if(NOT DEFINED MDBX_CXX_STANDARD)
+  if(DEFINED ENV{CMAKE_CXX_STANDARD})
+    set(CMAKE_CXX_STANDARD $ENV{CMAKE_CXX_STANDARD})
+  endif()
   if(DEFINED CMAKE_CXX_STANDARD)
     set(MDBX_CXX_STANDARD ${CMAKE_CXX_STANDARD})
+  elseif(NOT HAS_CXX23 LESS 0
+      AND NOT (CMAKE_COMPILER_IS_CLANG AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 12))
+    set(MDBX_CXX_STANDARD 23)
   elseif(NOT HAS_CXX20 LESS 0
       AND NOT (CMAKE_COMPILER_IS_CLANG AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 9))
     set(MDBX_CXX_STANDARD 20)

ChangeLog.md

@@ -1,8 +1,6 @@
 ChangeLog
 ---------
 
-## v0.11.x (in development)
-
 ### TODO
 
  - [Engage an "overlapped I/O" on Windows](https://github.com/erthink/libmdbx/issues/224).
@@ -16,11 +14,64 @@ ChangeLog
  - [Support for RAW devices](https://github.com/erthink/libmdbx/issues/124).
  - [Support MessagePack for Keys & Values](https://github.com/erthink/libmdbx/issues/115).
  - [Engage new terminology](https://github.com/erthink/libmdbx/issues/137).
- - Finalize C++ API (few typos and bugs are still maybe for now).
+ - Finalize C++ API (there is still a small chance for a few typos and bugs).
  - Packages for [Astra Linux](https://astralinux.ru/), [ALT Linux](https://www.altlinux.org/), [ROSA Linux](https://www.rosalinux.ru/), etc.
 
 
-## v0.10.5 at 2021-10-13
+## v0.11.2 at 2021-12-02
+
+Acknowledgements:
+
+ - [장세연 (Чан Се Ен)](https://github.com/sasgas) for contributing to C++ API.
+ - [Alain Picard](https://github.com/castortech) for [Java bindings](https://github.com/castortech/mdbxjni).
+ - [Alex Sharov](https://github.com/AskAlexSharov) for reporting and testing.
+ - [Kris Zyp](https://github.com/kriszyp) for reporting and testing.
+ - [Artem Vorotnikov](https://github.com/vorot93) for support [Rust wrapper](https://github.com/vorot93/libmdbx-rs).
+
+Fixes:
+
+ - [Fixed compilation](https://github.com/erthink/libmdbx/pull/239) with `devtoolset-9` on CentOS/RHEL 7.
+ - [Fixed unexpected `MDBX_PROBLEM` error](https://github.com/erthink/libmdbx/issues/242) because of update an obsolete meta-page.
+ - [Fixed returning `MDBX_NOTFOUND` error](https://github.com/erthink/libmdbx/issues/243) in case an inexact value found for `MDBX_GET_BOTH` operation.
+ - [Fixed compilation](https://github.com/erthink/libmdbx/issues/245) without kernel/libc-devel headers.
+
+Minors:
+
+ - Fixed `constexpr`-related macros for legacy compilers.
+ - Allowed to define 'CMAKE_CXX_STANDARD` using an environment variable.
+ - Simplified collection statistics of page operation .
+ - Added `MDBX_FORCE_BUILD_AS_MAIN_PROJECT` cmake option.
+ - Remove unneeded `#undef P_DIRTY`.
+
+
+## v0.11.1 at 2021-10-23
+
+### Backward compatibility break:
+
+The database format signature has been changed to prevent
+forward-interoperability with an previous releases, which may lead to a
+[false positive diagnosis of database corruption](https://github.com/erthink/libmdbx/issues/238)
+due to flaws of an old library versions.
+
+This change is mostly invisible:
+
+ - previously versions are unable to read/write a new DBs;
+ - but the new release is able to handle an old DBs and will silently upgrade ones.
+
+Acknowledgements:
+
+ - [Alex Sharov](https://github.com/AskAlexSharov) for reporting and testing.
+
+
+## v0.10.5 at 2021-10-13 (obsolete, please use v0.11.1)
+
+Unfortunately, the `v0.10.5` accidentally comes not full-compatible with previous releases:
+
+ - `v0.10.5` can read/processing DBs created by previous releases, i.e. the backward-compatibility is provided;
+ - however, previous releases may lead to false-corrupted state with DB that was touched by `v0.10.5`, i.e. the forward-compatibility is broken for `v0.10.4` and earlier.
+
+This cannot be fixed, as it requires fixing past versions, which as a result we will just get a current version.
+Therefore, it is recommended to use `v0.11.1` instead of `v0.10.5`.
 
 Acknowledgements:
 
@@ -42,7 +93,7 @@ Minors:
 
 Acknowledgements:
 
- - [Artem Vorotnikov](https://github.com/vorot93) for support [Rust wrapper](https://github.com/vorot93/mdbx-rs).
+ - [Artem Vorotnikov](https://github.com/vorot93) for support [Rust wrapper](https://github.com/vorot93/libmdbx-rs).
  - [Andrew Ashikhmin](https://github.com/yperbasis) for contributing to C++ API.
 
 Fixes:

GNUmakefile

@@ -35,7 +35,7 @@ CFLAGS  ?= -std=gnu11 -O2 -g -Wall -Werror -Wextra -Wpedantic -ffunction-section
 # -Wno-tautological-compare
 CXX     ?= g++
 # Choosing C++ standard with deferred simple variable expansion trick
-CXXSTD  ?= $(eval CXXSTD := $$(shell PROBE=$$$$([ -f mdbx.c++ ] && echo mdbx.c++ || echo src/mdbx.c++); for std in gnu++20 c++20 gnu++2a c++2a gnu++17 c++17 gnu++14 c++14 gnu+11 c++11; do $(CXX) -std=$$$${std} -c $$$${PROBE} -o /dev/null 2>/dev/null >/dev/null && echo "-std=$$$${std}" && exit; done))$(CXXSTD)
+CXXSTD  ?= $(eval CXXSTD := $$(shell PROBE=$$$$([ -f mdbx.c++ ] && echo mdbx.c++ || echo src/mdbx.c++); for std in gnu++23 c++23 gnu++2b c++2b gnu++20 c++20 gnu++2a c++2a gnu++17 c++17 gnu++1z c++1z gnu++14 c++14 gnu++1y c++1y gnu+11 c++11 gnu++0x c++0x; do $(CXX) -std=$$$${std} -c $$$${PROBE} -o /dev/null 2>std-$$$${std}.err >/dev/null && echo "-std=$$$${std}" && exit; done))$(CXXSTD)
 CXXFLAGS = $(CXXSTD) $(filter-out -std=gnu11,$(CFLAGS))
 
 # TIP: Try append '--no-as-needed,-lrt' for ability to built with modern glibc, but then use with the old.

README.md

@@ -566,13 +566,13 @@ Bindings
 | ------- | ------ | ------ |
 | Haskell | [libmdbx-hs](https://hackage.haskell.org/package/libmdbx) | [Francisco Vallarino](https://github.com/fjvallarino) |
 | Python (draft) | [python-bindings](https://github.com/erthink/libmdbx/commits/python-bindings) branch | [Noel Kuntze](https://github.com/Thermi)
-| NodeJS  | [lmdbx-store](https://github.com/kriszyp/lmdbx-store) | [Kris Zyp](https://github.com/kriszyp/)
+| NodeJS  | [lmdbx-js](https://github.com/kriszyp/lmdbx-js) | [Kris Zyp](https://github.com/kriszyp/)
 | NodeJS  | [node-mdbx](https://www.npmjs.com/package/node-mdbx/) | [Сергей Федотов](mailto:sergey.fedotov@corp.mail.ru) |
 | Ruby    | [ruby-mdbx](https://rubygems.org/gems/mdbx/) | [Mahlon E. Smith](https://github.com/mahlonsmith) |
 | Go      | [mdbx-go](https://github.com/torquem-ch/mdbx-go) | [Alex Sharov](https://github.com/AskAlexSharov) |
 | [Nim](https://en.wikipedia.org/wiki/Nim_(programming_language)) | [NimDBX](https://github.com/snej/nimdbx) | [Jens Alfke](https://github.com/snej)
-| Rust    | [mdbx-rs](https://github.com/vorot93/mdbx-rs)   | [Artem Vorotnikov](https://github.com/vorot93) |
-| Java (obsolete)   | [mdbxjni](https://github.com/castortech/mdbxjni)   | [Castor Technologies](https://castortech.com/) |
+| Rust    | [libmdbx-rs](https://github.com/vorot93/libmdbx-rs)   | [Artem Vorotnikov](https://github.com/vorot93) |
+| Java   | [mdbxjni](https://github.com/castortech/mdbxjni)   | [Castor Technologies](https://castortech.com/) |
 | .NET (obsolete)   | [mdbx.NET](https://github.com/wangjia184/mdbx.NET) | [Jerry Wang](https://github.com/wangjia184) |
 
 <!-- section-end -->

appveyor.yml

@@ -1,4 +1,4 @@
-version: 0.10.5.{build}
+version: 0.11.2.{build}
 
 environment:
   matrix:

mdbx.h

@@ -393,7 +393,8 @@ typedef mode_t mdbx_mode_t;
 #define MDBX_CXX01_CONSTEXPR __inline
 #define MDBX_CXX01_CONSTEXPR_VAR const
 #elif !defined(DOXYGEN) &&                                                     \
-    (!defined(__cpp_constexpr) || __cpp_constexpr < 200704L ||                 \
+    ((__cplusplus < 201103L && defined(__cpp_constexpr) &&                     \
+      __cpp_constexpr < 200704L) ||                                            \
      (defined(__LCC__) && __LCC__ < 124) ||                                    \
      (defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 407) &&          \
       !defined(__clang__) && !defined(__LCC__)) ||                             \
@@ -410,7 +411,7 @@ typedef mode_t mdbx_mode_t;
 #define MDBX_CXX11_CONSTEXPR __inline
 #define MDBX_CXX11_CONSTEXPR_VAR const
 #elif !defined(DOXYGEN) &&                                                     \
-    (!defined(__cpp_constexpr) || __cpp_constexpr < 201304 ||                  \
+    (!defined(__cpp_constexpr) || __cpp_constexpr < 201304L ||                 \
      (defined(__LCC__) && __LCC__ < 124) ||                                    \
      (defined(__GNUC__) && __GNUC__ < 6 && !defined(__clang__) &&              \
       !defined(__LCC__)) ||                                                    \
@@ -568,9 +569,9 @@ typedef mode_t mdbx_mode_t;
 extern "C" {
 #endif
 
-/* MDBX version 0.10.x */
+/* MDBX version 0.11.x */
 #define MDBX_VERSION_MAJOR 0
-#define MDBX_VERSION_MINOR 10
+#define MDBX_VERSION_MINOR 11
 
 #ifndef LIBMDBX_API
 #if defined(LIBMDBX_EXPORTS)
@@ -1382,10 +1383,10 @@ DEFINE_ENUM_FLAG_OPERATORS(MDBX_txn_flags_t)
 enum MDBX_db_flags_t {
   MDBX_DB_DEFAULTS = 0,
 
-  /** Use reverse string keys */
+  /** Use reverse string comparison for keys. */
   MDBX_REVERSEKEY = UINT32_C(0x02),
 
-  /** Use sorted duplicates, i.e. allow multi-values */
+  /** Use sorted duplicates, i.e. allow multi-values for a keys. */
   MDBX_DUPSORT = UINT32_C(0x04),
 
   /** Numeric keys in native byte order either uint32_t or uint64_t. The keys
@@ -1393,18 +1394,19 @@ enum MDBX_db_flags_t {
    * arguments. */
   MDBX_INTEGERKEY = UINT32_C(0x08),
 
-  /** With \ref MDBX_DUPSORT; sorted dup items have fixed size */
+  /** With \ref MDBX_DUPSORT; sorted dup items have fixed size. The data values
+   * must all be of the same size. */
   MDBX_DUPFIXED = UINT32_C(0x10),
 
   /** With \ref MDBX_DUPSORT and with \ref MDBX_DUPFIXED; dups are fixed size
-   * \ref MDBX_INTEGERKEY -style integers. The data values must all be of the
-   * same size and must be aligned while passing as arguments. */
+   * like \ref MDBX_INTEGERKEY -style integers. The data values must all be of
+   * the same size and must be aligned while passing as arguments. */
   MDBX_INTEGERDUP = UINT32_C(0x20),
 
-  /** With \ref MDBX_DUPSORT; use reverse string comparison */
+  /** With \ref MDBX_DUPSORT; use reverse string comparison for data values. */
   MDBX_REVERSEDUP = UINT32_C(0x40),
 
-  /** Create DB if not already existing */
+  /** Create DB if not already existing. */
   MDBX_CREATE = UINT32_C(0x40000),
 
   /** Opens an existing sub-database created with unknown flags.
@@ -1735,7 +1737,7 @@ enum MDBX_error_t {
 #ifdef ENODATA
   MDBX_ENODATA = ENODATA,
 #else
-  MDBX_ENODATA = -1,
+  MDBX_ENODATA = 9919 /* for compatibility with LLVM's C++ libraries/headers */,
 #endif /* ENODATA */
   MDBX_EINVAL = EINVAL,
   MDBX_EACCESS = EACCES,
@@ -3284,9 +3286,11 @@ struct MDBX_commit_latency {
   uint32_t gc;
   /** \brief Duration of internal audit if enabled. */
   uint32_t audit;
-  /** \brief Duration of writing dirty/modified data pages. */
+  /** \brief Duration of writing dirty/modified data pages to a filesystem,
+   * i.e. the summary duration of a `write()` syscalls during commit. */
   uint32_t write;
-  /** \brief Duration of syncing written data to the dist/storage. */
+  /** \brief Duration of syncing written data to the disk/storage, i.e.
+   * the duration of a `fdatasync()` or a `msync()` syscall during commit. */
   uint32_t sync;
   /** \brief Duration of transaction ending (releasing resources). */
   uint32_t ending;
@@ -3509,10 +3513,14 @@ LIBMDBX_API int mdbx_canary_get(const MDBX_txn *txn, MDBX_canary *canary);
  * The reasons to not using custom comparators are:
  *   - The order of records could not be validated without your code.
  *     So `mdbx_chk` utility will reports "wrong order" errors
- *     and the `-i` option is required to ignore ones.
+ *     and the `-i` option is required to suppress ones.
  *   - A records could not be ordered or sorted without your code.
- *     So mdbx_load utility should be used with `-a` option to preserve
- *     input data order. */
+ *     So `mdbx_load` utility should be used with `-a` option to preserve
+ *     input data order.
+ *   - However, the custom comparators feature will never be removed.
+ *     You have been warned but still can use custom comparators knowing
+ *     about the issues noted above. In this case you should ignore `deprecated`
+ *     warnings or define `MDBX_DEPRECATED` macro to empty to avoid ones. */
 typedef int(MDBX_cmp_func)(const MDBX_val *a,
                            const MDBX_val *b) MDBX_CXX17_NOEXCEPT;
 

mdbx.h++

@@ -286,7 +286,8 @@ class cursor;
 class cursor_managed;
 
 #if defined(DOXYGEN) ||                                                        \
-    defined(__cpp_lib_memory_resource) && __cpp_lib_memory_resource >= 201603L
+    (defined(__cpp_lib_memory_resource) &&                                     \
+     __cpp_lib_memory_resource >= 201603L && _GLIBCXX_USE_CXX11_ABI)
 /// \brief Default polymorphic allocator for modern code.
 using polymorphic_allocator = ::std::pmr::string::allocator_type;
 #endif /* __cpp_lib_memory_resource >= 201603L */
@@ -476,30 +477,23 @@ static MDBX_CXX20_CONSTEXPR void *memcpy(void *dest, const void *src,
 
 template <typename T>
 concept MutableByteProducer = requires(T a, char array[42]) {
-  { a.is_empty() }
-  ->std::same_as<bool>;
-  { a.envisage_result_length() }
-  ->std::same_as<size_t>;
-  { a.write_bytes(&array[0], size_t(42)) }
-  ->std::same_as<char *>;
+  { a.is_empty() } -> std::same_as<bool>;
+  { a.envisage_result_length() } -> std::same_as<size_t>;
+  { a.write_bytes(&array[0], size_t(42)) } -> std::same_as<char *>;
 };
 
 template <typename T>
 concept ImmutableByteProducer = requires(const T &a, char array[42]) {
-  { a.is_empty() }
-  ->std::same_as<bool>;
-  { a.envisage_result_length() }
-  ->std::same_as<size_t>;
-  { a.write_bytes(&array[0], size_t(42)) }
-  ->std::same_as<char *>;
+  { a.is_empty() } -> std::same_as<bool>;
+  { a.envisage_result_length() } -> std::same_as<size_t>;
+  { a.write_bytes(&array[0], size_t(42)) } -> std::same_as<char *>;
 };
 
 template <typename T>
-concept SliceTranscoder =
-    ImmutableByteProducer<T> &&requires(const slice &source, const T &a) {
+concept SliceTranscoder = ImmutableByteProducer<T> &&
+    requires(const slice &source, const T &a) {
   T(source);
-  { a.is_erroneous() }
-  ->std::same_as<bool>;
+  { a.is_erroneous() } -> std::same_as<bool>;
 };
 
 #endif /* __cpp_concepts >= 201907L*/
@@ -4404,9 +4398,9 @@ MDBX_CXX14_CONSTEXPR intptr_t slice::compare_fast(const slice &a,
                                                   const slice &b) noexcept {
   const intptr_t diff = intptr_t(a.length()) - intptr_t(b.length());
   return diff ? diff
-              : MDBX_UNLIKELY(a.length() == 0 || a.data() == b.data())
-                    ? 0
-                    : memcmp(a.data(), b.data(), a.length());
+         : MDBX_UNLIKELY(a.length() == 0 || a.data() == b.data())
+             ? 0
+             : memcmp(a.data(), b.data(), a.length());
 }
 
 MDBX_CXX14_CONSTEXPR intptr_t

packages/buildroot/0001-package-libmdbx-new-package-library-database.patch

@@ -1,9 +1,9 @@
-From ce7b70a572cf77d8f37e5047d5d9c8361b2675ae Mon Sep 17 00:00:00 2001
+From f732fc79456f3b296543ab2625d35eeef2655618 Mon Sep 17 00:00:00 2001
 From: Leonid Yuriev <leo@yuriev.ru>
-Date: Sun, 10 Oct 2021 15:31:40 +0300
+Date: Sun, 24 Oct 2021 20:13:33 +0300
 Subject: [PATCH] package/libmdbx: new package (library/database).
 
-This patch adds libmdbx v0.10.4:
+This patch adds libmdbx v0.11.1:
  - libmdbx is one of the fastest compact embeddable key-value ACID database.
  - libmdbx has a specific set of properties and capabilities,
    focused on creating unique lightweight solutions.
@@ -103,18 +103,18 @@ index 0000000000..d13f73938f
 +		!BR2_TOOLCHAIN_GCC_AT_LEAST_4_4
 diff --git a/package/libmdbx/libmdbx.hash b/package/libmdbx/libmdbx.hash
 new file mode 100644
-index 0000000000..326cf57bb6
+index 0000000000..c8b50f9ac3
 --- /dev/null
 +++ b/package/libmdbx/libmdbx.hash
 @@ -0,0 +1,5 @@
 +# Hashes from: https://github.com/erthink/libmdbx/releases/
-+sha256  e11d5339a1e1cc34407898933b62a208936fd761a2cc31e11244d581d1d2b5d0  libmdbx-amalgamated-0.10.4.tar.gz
++sha256  f954ba8c9768914a92c2b46aac0d66bec674dbb4d7b0f01e362ea2921746ddaa  libmdbx-amalgamated-0.11.1.tar.gz
 +
 +# Locally calculated
 +sha256  310fe25c858a9515fc8c8d7d1f24a67c9496f84a91e0a0e41ea9975b1371e569  LICENSE
 diff --git a/package/libmdbx/libmdbx.mk b/package/libmdbx/libmdbx.mk
 new file mode 100644
-index 0000000000..f38e4a533b
+index 0000000000..02d00b1a5a
 --- /dev/null
 +++ b/package/libmdbx/libmdbx.mk
 @@ -0,0 +1,42 @@
@@ -124,7 +124,7 @@ index 0000000000..f38e4a533b
 +#
 +################################################################################
 +
-+LIBMDBX_VERSION = 0.10.4
++LIBMDBX_VERSION = 0.11.1
 +LIBMDBX_SOURCE = libmdbx-amalgamated-$(LIBMDBX_VERSION).tar.gz
 +LIBMDBX_SITE = https://github.com/erthink/libmdbx/releases/download/v$(LIBMDBX_VERSION)
 +LIBMDBX_SUPPORTS_IN_SOURCE_BUILD = NO
@@ -161,5 +161,5 @@ index 0000000000..f38e4a533b
 +
 +$(eval $(cmake-package))
 -- 
-2.33.0
+2.33.1
 

src/core.c

@@ -823,6 +823,70 @@ size_t __hot mdbx_e2k_strnlen_bug_workaround(const char *s, size_t maxlen) {
 /*------------------------------------------------------------------------------
  * safe read/write volatile 64-bit fields on 32-bit architectures. */
 
+MDBX_MAYBE_UNUSED static __always_inline uint64_t
+atomic_store64(MDBX_atomic_uint64_t *p, const uint64_t value,
+               enum MDBX_memory_order order) {
+  STATIC_ASSERT(sizeof(MDBX_atomic_uint64_t) == 8);
+#if MDBX_64BIT_ATOMIC
+#ifdef MDBX_HAVE_C11ATOMICS
+  assert(atomic_is_lock_free(MDBX_c11a_rw(uint64_t, p)));
+  atomic_store_explicit(MDBX_c11a_rw(uint64_t, p), value, mo_c11_store(order));
+#else  /* MDBX_HAVE_C11ATOMICS */
+  if (order != mo_Relaxed)
+    mdbx_compiler_barrier();
+  p->weak = value;
+  mdbx_memory_fence(order, true);
+#endif /* MDBX_HAVE_C11ATOMICS */
+#else  /* !MDBX_64BIT_ATOMIC */
+  mdbx_compiler_barrier();
+  atomic_store32(&p->low, (uint32_t)value, mo_Relaxed);
+  mdbx_jitter4testing(true);
+  atomic_store32(&p->high, (uint32_t)(value >> 32), order);
+  mdbx_jitter4testing(true);
+#endif /* !MDBX_64BIT_ATOMIC */
+  return value;
+}
+
+MDBX_MAYBE_UNUSED static
+#if MDBX_64BIT_ATOMIC
+    __always_inline
+#endif /* MDBX_64BIT_ATOMIC */
+        uint64_t
+        atomic_load64(const MDBX_atomic_uint64_t *p,
+                      enum MDBX_memory_order order) {
+  STATIC_ASSERT(sizeof(MDBX_atomic_uint64_t) == 8);
+#if MDBX_64BIT_ATOMIC
+#ifdef MDBX_HAVE_C11ATOMICS
+  assert(atomic_is_lock_free(MDBX_c11a_ro(uint64_t, p)));
+  return atomic_load_explicit(MDBX_c11a_ro(uint64_t, p), mo_c11_load(order));
+#else  /* MDBX_HAVE_C11ATOMICS */
+  mdbx_memory_fence(order, false);
+  const uint64_t value = p->weak;
+  if (order != mo_Relaxed)
+    mdbx_compiler_barrier();
+  return value;
+#endif /* MDBX_HAVE_C11ATOMICS */
+#else  /* !MDBX_64BIT_ATOMIC */
+  mdbx_compiler_barrier();
+  uint64_t value = (uint64_t)atomic_load32(&p->high, order) << 32;
+  mdbx_jitter4testing(true);
+  value |= atomic_load32(&p->low, (order == mo_Relaxed) ? mo_Relaxed
+                                                        : mo_AcquireRelease);
+  mdbx_jitter4testing(true);
+  for (;;) {
+    mdbx_compiler_barrier();
+    uint64_t again = (uint64_t)atomic_load32(&p->high, order) << 32;
+    mdbx_jitter4testing(true);
+    again |= atomic_load32(&p->low, (order == mo_Relaxed) ? mo_Relaxed
+                                                          : mo_AcquireRelease);
+    mdbx_jitter4testing(true);
+    if (likely(value == again))
+      return value;
+    value = again;
+  }
+#endif /* !MDBX_64BIT_ATOMIC */
+}
+
 static __always_inline void atomic_yield(void) {
 #if defined(_WIN32) || defined(_WIN64)
   YieldProcessor();
@@ -1509,9 +1573,6 @@ static int uniq_peek(const mdbx_mmap_t *pending, mdbx_mmap_t *scan) {
     rc = MDBX_SUCCESS;
   } else {
     bait = 0 /* hush MSVC warning */;
-#if MDBX_ENABLE_PGOP_STAT
-    safe64_inc(&scan_lck->mti_pgop_stat.wops, 1);
-#endif /* MDBX_ENABLE_PGOP_STAT */
     rc = mdbx_msync(scan, 0, sizeof(MDBX_lockinfo), MDBX_SYNC_DATA);
     if (rc == MDBX_SUCCESS)
       rc = mdbx_pread(pending->fd, &bait, sizeof(scan_lck->mti_bait_uniqueness),
@@ -1568,9 +1629,6 @@ __cold static int uniq_check(const mdbx_mmap_t *pending, MDBX_env **found) {
     if (err == MDBX_RESULT_TRUE)
       err = uniq_poke(pending, &scan->me_lck_mmap, &salt);
     if (err == MDBX_RESULT_TRUE) {
-#if MDBX_ENABLE_PGOP_STAT
-      safe64_inc(&scan->me_lck_mmap.lck->mti_pgop_stat.wops, 1);
-#endif /* MDBX_ENABLE_PGOP_STAT */
       (void)mdbx_msync(&scan->me_lck_mmap, 0, sizeof(MDBX_lockinfo),
                        MDBX_SYNC_NONE);
       err = uniq_poke(pending, &scan->me_lck_mmap, &salt);
@@ -4921,7 +4979,7 @@ static int mdbx_iov_write(MDBX_txn *const txn, struct mdbx_iov_ctx *ctx) {
                     bytes2pgno(env, ctx->iov[i].iov_len));
 
 #if MDBX_ENABLE_PGOP_STAT
-  safe64_inc(&txn->mt_env->me_lck->mti_pgop_stat.wops, ctx->iov_items);
+  txn->mt_env->me_lck->mti_pgop_stat.wops.weak += ctx->iov_items;
 #endif /* MDBX_ENABLE_PGOP_STAT */
   ctx->iov_items = 0;
   ctx->iov_bytes = 0;
@@ -4986,7 +5044,7 @@ static int spill_page(MDBX_txn *txn, struct mdbx_iov_ctx *ctx, MDBX_page *dp,
     err = mdbx_pnl_append_range(true, &txn->tw.spill_pages, pgno << 1, npages);
 #if MDBX_ENABLE_PGOP_STAT
     if (likely(err == MDBX_SUCCESS))
-      safe64_inc(&txn->mt_env->me_lck->mti_pgop_stat.spill, npages);
+      txn->mt_env->me_lck->mti_pgop_stat.spill.weak += npages;
 #endif /* MDBX_ENABLE_PGOP_STAT */
   }
   return err;
@@ -5044,9 +5102,9 @@ static unsigned spill_prio(const MDBX_txn *txn, const unsigned i,
   MDBX_page *const dp = dl->items[i].ptr;
   if (dp->mp_flags & (P_LOOSE | P_SPILLED)) {
     mdbx_debug("skip %s %u page %" PRIaPGNO,
-               (dp->mp_flags & P_LOOSE)
-                   ? "loose"
-                   : (dp->mp_flags & P_LOOSE) ? "loose" : "parent-spilled",
+               (dp->mp_flags & P_LOOSE)   ? "loose"
+               : (dp->mp_flags & P_LOOSE) ? "loose"
+                                          : "parent-spilled",
                npages, pgno);
     return 256;
   }
@@ -5167,7 +5225,7 @@ static int mdbx_txn_spill(MDBX_txn *const txn, MDBX_cursor *const m0,
     if (!MDBX_FAKE_SPILL_WRITEMAP && ctx.flush_end > ctx.flush_begin) {
       MDBX_env *const env = txn->mt_env;
 #if MDBX_ENABLE_PGOP_STAT
-      safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+      env->me_lck->mti_pgop_stat.wops.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
       rc = mdbx_msync(&env->me_dxb_mmap,
                       pgno_align2os_bytes(env, ctx.flush_begin),
@@ -5994,7 +6052,7 @@ __cold static int mdbx_mapresize(MDBX_env *env, const pgno_t used_pgno,
 
   if ((env->me_flags & MDBX_WRITEMAP) && env->me_lck->mti_unsynced_pages.weak) {
 #if MDBX_ENABLE_PGOP_STAT
-    safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+    env->me_lck->mti_pgop_stat.wops.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
     rc = mdbx_msync(&env->me_dxb_mmap, 0, pgno_align2os_bytes(env, used_pgno),
                     MDBX_SYNC_NONE);
@@ -6145,7 +6203,7 @@ static int mdbx_meta_unsteady(MDBX_env *env, const txnid_t last_steady,
 
 __cold static int mdbx_wipe_steady(MDBX_env *env, const txnid_t last_steady) {
 #if MDBX_ENABLE_PGOP_STAT
-  safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+  env->me_lck->mti_pgop_stat.wops.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
   const mdbx_filehandle_t fd = (env->me_dsync_fd != INVALID_HANDLE_VALUE)
                                    ? env->me_dsync_fd
@@ -6765,7 +6823,7 @@ mdbx_page_unspill(MDBX_txn *const txn, const MDBX_page *const mp) {
     if (unlikely(ret.err != MDBX_SUCCESS))
       return ret;
 #if MDBX_ENABLE_PGOP_STAT
-    safe64_inc(&txn->mt_env->me_lck->mti_pgop_stat.unspill, npages);
+    txn->mt_env->me_lck->mti_pgop_stat.unspill.weak += npages;
 #endif /* MDBX_ENABLE_PGOP_STAT */
     ret.page->mp_flags |= (scan == txn) ? 0 : P_SPILLED;
     ret.err = MDBX_SUCCESS;
@@ -6838,7 +6896,7 @@ __hot static int mdbx_page_touch(MDBX_cursor *mc) {
     }
 
 #if MDBX_ENABLE_PGOP_STAT
-    safe64_inc(&txn->mt_env->me_lck->mti_pgop_stat.cow, 1);
+    txn->mt_env->me_lck->mti_pgop_stat.cow.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
     mdbx_page_copy(np, mp, txn->mt_env->me_psize);
     np->mp_pgno = pgno;
@@ -6881,7 +6939,7 @@ __hot static int mdbx_page_touch(MDBX_cursor *mc) {
       goto fail;
 
 #if MDBX_ENABLE_PGOP_STAT
-    safe64_inc(&txn->mt_env->me_lck->mti_pgop_stat.clone, 1);
+    txn->mt_env->me_lck->mti_pgop_stat.clone.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
   }
 
@@ -6959,7 +7017,7 @@ __cold static int mdbx_env_sync_internal(MDBX_env *env, bool force,
         const size_t usedbytes = pgno_align2os_bytes(env, head->mm_geo.next);
 
 #if MDBX_ENABLE_PGOP_STAT
-        safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+        env->me_lck->mti_pgop_stat.wops.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
         mdbx_txn_unlock(env);
 
@@ -7009,7 +7067,17 @@ fastpath:
     if (atomic_load32(&env->me_lck->mti_meta_sync_txnid, mo_Relaxed) !=
         (uint32_t)head_txnid) {
 #if MDBX_ENABLE_PGOP_STAT
-      safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+      if (need_unlock)
+        env->me_lck->mti_pgop_stat.wops.weak += 1;
+#if MDBX_64BIT_ATOMIC
+      else {
+        MDBX_atomic_uint64_t *wops = &env->me_lck->mti_pgop_stat.wops;
+        while (unlikely(!atomic_cas64(wops, wops->weak, wops->weak + 1)))
+          atomic_yield();
+      }
+#else
+        /* loose the env->me_lck->mti_pgop_stat.wops.weak increment */
+#endif /* MDBX_64BIT_ATOMIC */
 #endif /* MDBX_ENABLE_PGOP_STAT */
       rc = (flags & MDBX_WRITEMAP)
                ? mdbx_msync(&env->me_dxb_mmap, 0,
@@ -9136,7 +9204,8 @@ retry_noaccount:
           txn->tw.lifo_reclaimed
               ? (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) -
                     reused_gc_slot + 1
-              : (gc_rid < INT16_MAX) ? (unsigned)gc_rid : INT16_MAX;
+          : (gc_rid < INT16_MAX) ? (unsigned)gc_rid
+                                 : INT16_MAX;
       if (avail_gc_slots > 1) {
         if (chunk < env->me_maxgc_ov1page * 2)
           chunk /= 2;
@@ -9169,10 +9238,10 @@ retry_noaccount:
             }
 
             chunk = (avail >= tail) ? tail - span
-                                    : (avail_gc_slots > 3 &&
-                                       reused_gc_slot < prefer_max_scatter - 3)
-                                          ? avail - span
-                                          : tail;
+                    : (avail_gc_slots > 3 &&
+                       reused_gc_slot < prefer_max_scatter - 3)
+                        ? avail - span
+                        : tail;
           }
         }
       }
@@ -10124,7 +10193,8 @@ static int mdbx_validate_meta(MDBX_env *env, MDBX_meta *const meta,
   const uint64_t magic_and_version =
       unaligned_peek_u64(4, &meta->mm_magic_and_version);
   if (unlikely(magic_and_version != MDBX_DATA_MAGIC &&
-               magic_and_version != MDBX_DATA_MAGIC_DEVEL)) {
+               magic_and_version != MDBX_DATA_MAGIC_LEGACY_COMPAT &&
+               magic_and_version != MDBX_DATA_MAGIC_LEGACY_DEVEL)) {
     mdbx_error("meta[%u] has invalid magic/version %" PRIx64, meta_number,
                magic_and_version);
     return ((magic_and_version >> 8) != MDBX_MAGIC) ? MDBX_INVALID
@@ -10374,11 +10444,10 @@ __cold static int mdbx_read_header(MDBX_env *env, MDBX_meta *dest,
   unsigned guess_pagesize = 0;
   for (unsigned loop_count = 0; loop_count < loop_limit; ++loop_count) {
     const unsigned meta_number = loop_count % NUM_METAS;
-    const unsigned offset =
-        (guess_pagesize
-             ? guess_pagesize
-             : (loop_count > NUM_METAS) ? env->me_psize : env->me_os_psize) *
-        meta_number;
+    const unsigned offset = (guess_pagesize             ? guess_pagesize
+                             : (loop_count > NUM_METAS) ? env->me_psize
+                                                        : env->me_os_psize) *
+                            meta_number;
 
     char buffer[MIN_PAGESIZE];
     unsigned retryleft = 42;
@@ -10487,9 +10556,7 @@ __cold static MDBX_page *mdbx_meta_model(const MDBX_env *env, MDBX_page *model,
                        pages2pv(pv2pages(model_meta->mm_geo.shrink_pv)));
 
   model_meta->mm_psize = env->me_psize;
-  model_meta->mm_flags = (uint16_t)env->me_flags & DB_PERSISTENT_FLAGS;
-  model_meta->mm_flags =
-      MDBX_INTEGERKEY; /* this is mm_dbs[FREE_DBI].md_flags */
+  model_meta->mm_dbs[FREE_DBI].md_flags = MDBX_INTEGERKEY;
   model_meta->mm_dbs[FREE_DBI].md_root = P_INVALID;
   model_meta->mm_dbs[MAIN_DBI].md_root = P_INVALID;
   mdbx_meta_set_txnid(env, model_meta, MIN_TXNID + num);
@@ -10518,9 +10585,9 @@ static size_t mdbx_madvise_threshold(const MDBX_env *env,
   const unsigned factor = 9;
   const size_t threshold = (largest_bytes < (65536ul << factor))
                                ? 65536 /* minimal threshold */
-                               : (largest_bytes > (MEGABYTE * 4 << factor))
-                                     ? MEGABYTE * 4 /* maximal threshold */
-                                     : largest_bytes >> factor;
+                           : (largest_bytes > (MEGABYTE * 4 << factor))
+                               ? MEGABYTE * 4 /* maximal threshold */
+                               : largest_bytes >> factor;
   return bytes_align2os_bytes(env, threshold);
 }
 #endif /* MDBX_ENABLE_MADVISE */
@@ -10672,7 +10739,7 @@ static int mdbx_sync_locked(MDBX_env *env, unsigned flags,
         mode_bits |= MDBX_SYNC_IODQ;
     }
 #if MDBX_ENABLE_PGOP_STAT
-    safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+    env->me_lck->mti_pgop_stat.wops.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
     if (flags & MDBX_WRITEMAP)
       rc =
@@ -10735,17 +10802,23 @@ static int mdbx_sync_locked(MDBX_env *env, unsigned flags,
 
   mdbx_debug("meta0: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
              "/%" PRIaPGNO,
-             (meta0 == head) ? "head" : (meta0 == target) ? "tail" : "stay",
+             (meta0 == head)     ? "head"
+             : (meta0 == target) ? "tail"
+                                 : "stay",
              mdbx_durable_str(meta0), mdbx_meta_txnid_fluid(env, meta0),
              meta0->mm_dbs[MAIN_DBI].md_root, meta0->mm_dbs[FREE_DBI].md_root);
   mdbx_debug("meta1: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
              "/%" PRIaPGNO,
-             (meta1 == head) ? "head" : (meta1 == target) ? "tail" : "stay",
+             (meta1 == head)     ? "head"
+             : (meta1 == target) ? "tail"
+                                 : "stay",
              mdbx_durable_str(meta1), mdbx_meta_txnid_fluid(env, meta1),
              meta1->mm_dbs[MAIN_DBI].md_root, meta1->mm_dbs[FREE_DBI].md_root);
   mdbx_debug("meta2: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
              "/%" PRIaPGNO,
-             (meta2 == head) ? "head" : (meta2 == target) ? "tail" : "stay",
+             (meta2 == head)     ? "head"
+             : (meta2 == target) ? "tail"
+                                 : "stay",
              mdbx_durable_str(meta2), mdbx_meta_txnid_fluid(env, meta2),
              meta2->mm_dbs[MAIN_DBI].md_root, meta2->mm_dbs[FREE_DBI].md_root);
 
@@ -10758,7 +10831,7 @@ static int mdbx_sync_locked(MDBX_env *env, unsigned flags,
               target == head || mdbx_meta_txnid_stable(env, target) <
                                     unaligned_peek_u64(4, pending->mm_txnid_a));
 #if MDBX_ENABLE_PGOP_STAT
-  safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+  env->me_lck->mti_pgop_stat.wops.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
   if (flags & MDBX_WRITEMAP) {
     mdbx_jitter4testing(true);
@@ -10769,7 +10842,7 @@ static int mdbx_sync_locked(MDBX_env *env, unsigned flags,
       unaligned_poke_u64(4, target->mm_datasync_sign, MDBX_DATASIGN_WEAK);
 #ifndef NDEBUG
       /* debug: provoke failure to catch a violators, but don't touch mm_psize
-       * and mm_flags to allow readers catch actual pagesize. */
+       * to allow readers catch actual pagesize. */
       uint8_t *provoke_begin = (uint8_t *)&target->mm_dbs[FREE_DBI].md_root;
       uint8_t *provoke_end = (uint8_t *)&target->mm_datasync_sign;
       memset(provoke_begin, 0xCC, provoke_end - provoke_begin);
@@ -10817,7 +10890,7 @@ static int mdbx_sync_locked(MDBX_env *env, unsigned flags,
                                      ? env->me_dsync_fd
                                      : env->me_lazy_fd;
 #if MDBX_ENABLE_PGOP_STAT
-    safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+    env->me_lck->mti_pgop_stat.wops.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
     rc = mdbx_pwrite(fd, pending, sizeof(MDBX_meta),
                      (uint8_t *)target - env->me_map);
@@ -10868,12 +10941,15 @@ fail:
 
 static void recalculate_merge_threshold(MDBX_env *env) {
   const unsigned bytes = page_space(env);
-  env->me_merge_threshold = (uint16_t)(
-      bytes - (bytes * env->me_options.merge_threshold_16dot16_percent >> 16));
-  env->me_merge_threshold_gc = (uint16_t)(
-      bytes - ((env->me_options.merge_threshold_16dot16_percent > 19005)
-                   ? bytes / 3 /* 33 % */
-                   : bytes / 4 /* 25 % */));
+  env->me_merge_threshold =
+      (uint16_t)(bytes -
+                 (bytes * env->me_options.merge_threshold_16dot16_percent >>
+                  16));
+  env->me_merge_threshold_gc =
+      (uint16_t)(bytes -
+                 ((env->me_options.merge_threshold_16dot16_percent > 19005)
+                      ? bytes / 3 /* 33 % */
+                      : bytes / 4 /* 25 % */));
 }
 
 __cold static void mdbx_setup_pagesize(MDBX_env *env, const size_t pagesize) {
@@ -11867,6 +11943,31 @@ __cold static int mdbx_setup_dxb(MDBX_env *env, const int lck_rc,
 
     atomic_store32(&env->me_lck->mti_discarded_tail,
                    bytes2pgno(env, used_aligned2os_bytes), mo_Relaxed);
+
+    if ((env->me_flags & MDBX_RDONLY) == 0 && env->me_stuck_meta < 0) {
+      for (int n = 0; n < NUM_METAS; ++n) {
+        MDBX_meta *const pmeta = METAPAGE(env, n);
+        if (unlikely(unaligned_peek_u64(4, &pmeta->mm_magic_and_version) !=
+                     MDBX_DATA_MAGIC)) {
+          const txnid_t txnid = mdbx_meta_txnid_fluid(env, pmeta);
+          mdbx_notice("%s %s"
+                      "meta[%u], txnid %" PRIaTXN,
+                      "updating db-format signature for",
+                      META_IS_STEADY(pmeta) ? "stead-" : "weak-", n, txnid);
+          err = mdbx_override_meta(env, n, txnid, pmeta);
+          if (unlikely(err != MDBX_SUCCESS) &&
+              /* Just ignore the MDBX_PROBLEM error, since here it is
+               * returned only in case of the attempt to upgrade an obsolete
+               * meta-page that is invalid for current state of a DB,
+               * e.g. after shrinking DB file */
+              err != MDBX_PROBLEM) {
+            mdbx_error("%s meta[%u], txnid %" PRIaTXN ", error %d",
+                       "updating db-format signature for", n, txnid, err);
+            return err;
+          }
+        }
+      }
+    }
   } /* lck exclusive, lck_rc == MDBX_RESULT_TRUE */
 
   //---------------------------------------------------- setup madvise/readahead
@@ -12196,7 +12297,7 @@ __cold static int __must_check_result mdbx_override_meta(
     return MDBX_PROBLEM;
 
 #if MDBX_ENABLE_PGOP_STAT
-  safe64_inc(&env->me_lck->mti_pgop_stat.wops, 1);
+  env->me_lck->mti_pgop_stat.wops.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
   if (env->me_flags & MDBX_WRITEMAP) {
     rc = mdbx_msync(&env->me_dxb_mmap, 0,
@@ -13116,10 +13217,11 @@ mdbx_page_get_ex(MDBX_cursor *const mc, const pgno_t pgno,
   mdbx_tassert(txn, front <= txn->mt_front);
   if (unlikely(pgno >= txn->mt_next_pgno)) {
     mdbx_error("page #%" PRIaPGNO " beyond next-pgno", pgno);
+  notfound:
     ret.page = nullptr;
-  corrupted:
-    mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
     ret.err = MDBX_PAGE_NOTFOUND;
+  bailout:
+    mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
     return ret;
   }
 
@@ -13159,33 +13261,36 @@ dirty:
              "mismatch actual pgno (%" PRIaPGNO ") != expected (%" PRIaPGNO
              ")\n",
              ret.page->mp_pgno, pgno);
-    goto corrupted;
+    goto notfound;
   }
 
 #if !MDBX_DISABLE_PAGECHECKS
   if (unlikely(ret.page->mp_flags & P_ILL_BITS)) {
-    bad_page(ret.page, "invalid page's flags (%u)\n", ret.page->mp_flags);
-    goto corrupted;
+    ret.err =
+        bad_page(ret.page, "invalid page's flags (%u)\n", ret.page->mp_flags);
+    goto bailout;
   }
 
   if (unlikely(ret.page->mp_txnid > front) &&
       unlikely(ret.page->mp_txnid > txn->mt_front || front < txn->mt_txnid)) {
-    bad_page(ret.page,
-             "invalid page txnid (%" PRIaTXN ") for %s' txnid (%" PRIaTXN ")\n",
-             ret.page->mp_txnid,
-             (front == txn->mt_front && front != txn->mt_txnid) ? "front-txn"
-                                                                : "parent-page",
-             front);
-    goto corrupted;
+    ret.err = bad_page(
+        ret.page,
+        "invalid page txnid (%" PRIaTXN ") for %s' txnid (%" PRIaTXN ")\n",
+        ret.page->mp_txnid,
+        (front == txn->mt_front && front != txn->mt_txnid) ? "front-txn"
+                                                           : "parent-page",
+        front);
+    goto bailout;
   }
 
   if (unlikely((ret.page->mp_upper < ret.page->mp_lower ||
                 ((ret.page->mp_lower | ret.page->mp_upper) & 1) ||
                 PAGEHDRSZ + ret.page->mp_upper > env->me_psize) &&
                !IS_OVERFLOW(ret.page))) {
-    bad_page(ret.page, "invalid page lower(%u)/upper(%u) with limit (%u)\n",
-             ret.page->mp_lower, ret.page->mp_upper, page_space(env));
-    goto corrupted;
+    ret.err =
+        bad_page(ret.page, "invalid page lower(%u)/upper(%u) with limit (%u)\n",
+                 ret.page->mp_lower, ret.page->mp_upper, page_space(env));
+    goto bailout;
   }
 #endif /* !MDBX_DISABLE_PAGECHECKS */
 
@@ -13430,7 +13535,7 @@ __hot static int mdbx_page_search(MDBX_cursor *mc, const MDBX_val *key,
         break;
       }
     while (unlikely((scan = scan->mt_parent) != nullptr));
-    if (unlikely((rc = mdbx_page_get(mc, root, &mc->mc_pg[0], pp_txnid) != 0)))
+    if (unlikely((rc = mdbx_page_get(mc, root, &mc->mc_pg[0], pp_txnid)) != 0))
       return rc;
   }
 
@@ -13636,16 +13741,16 @@ static int mdbx_cursor_next(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
   MDBX_node *node;
   int rc;
 
-  if ((mc->mc_flags & C_DEL) && op == MDBX_NEXT_DUP)
+  if (unlikely(mc->mc_flags & C_DEL) && op == MDBX_NEXT_DUP)
     return MDBX_NOTFOUND;
 
-  if (!(mc->mc_flags & C_INITIALIZED))
+  if (unlikely(!(mc->mc_flags & C_INITIALIZED)))
     return mdbx_cursor_first(mc, key, data);
 
   mp = mc->mc_pg[mc->mc_top];
-  if (mc->mc_flags & C_EOF) {
+  if (unlikely(mc->mc_flags & C_EOF)) {
     if (mc->mc_ki[mc->mc_top] + 1u >= page_numkeys(mp))
-      return MDBX_NOTFOUND;
+      return (mc->mc_flags & C_SUB) ? MDBX_NOTFOUND : MDBX_ENODATA;
     mc->mc_flags ^= C_EOF;
   }
 
@@ -13737,10 +13842,10 @@ static int mdbx_cursor_prev(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
   MDBX_node *node;
   int rc;
 
-  if ((mc->mc_flags & C_DEL) && op == MDBX_PREV_DUP)
+  if (unlikely(mc->mc_flags & C_DEL) && op == MDBX_PREV_DUP)
     return MDBX_NOTFOUND;
 
-  if (!(mc->mc_flags & C_INITIALIZED)) {
+  if (unlikely(!(mc->mc_flags & C_INITIALIZED))) {
     rc = mdbx_cursor_last(mc, key, data);
     if (unlikely(rc))
       return rc;
@@ -14043,6 +14148,10 @@ got_node:
                             MDBX_SET_RANGE);
       if (unlikely(ret.err != MDBX_SUCCESS))
         return ret;
+      if (op == MDBX_GET_BOTH && !ret.exact) {
+        ret.err = MDBX_NOTFOUND;
+        return ret;
+      }
     }
   } else if (likely(data)) {
     if (op == MDBX_GET_BOTH || op == MDBX_GET_BOTH_RANGE) {
@@ -14074,12 +14183,12 @@ got_node:
           break;
         }
       }
-      MDBX_val olddata;
-      ret.err = mdbx_node_read(mc, node, &olddata,
+      MDBX_val actual_data;
+      ret.err = mdbx_node_read(mc, node, &actual_data,
                                pp_txnid4chk(mc->mc_pg[mc->mc_top], mc->mc_txn));
       if (unlikely(ret.err != MDBX_SUCCESS))
         return ret;
-      const int cmp = mc->mc_dbx->md_dcmp(&aligned_data, &olddata);
+      const int cmp = mc->mc_dbx->md_dcmp(&aligned_data, &actual_data);
       if (cmp) {
         mdbx_cassert(mc, mc->mc_ki[mc->mc_top] <
                                  page_numkeys(mc->mc_pg[mc->mc_top]) ||
@@ -14089,7 +14198,7 @@ got_node:
           return ret;
         }
       }
-      *data = olddata;
+      *data = actual_data;
     } else {
       ret.err = mdbx_node_read(mc, node, data,
                                pp_txnid4chk(mc->mc_pg[mc->mc_top], mc->mc_txn));
@@ -14234,6 +14343,8 @@ int mdbx_cursor_get(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
     const unsigned nkeys = page_numkeys(mp);
     if (mc->mc_ki[mc->mc_top] >= nkeys) {
       mdbx_cassert(mc, nkeys <= UINT16_MAX);
+      if (mc->mc_flags & C_EOF)
+        return MDBX_ENODATA;
       mc->mc_ki[mc->mc_top] = (uint16_t)nkeys;
       mc->mc_flags |= C_EOF;
       return MDBX_NOTFOUND;
@@ -14701,24 +14812,24 @@ int mdbx_cursor_put(MDBX_cursor *mc, const MDBX_val *key, MDBX_val *data,
           rc = MDBX_NOTFOUND;
           exact = false;
         } else /* checking for early exit without dirtying pages */
-            if (!(flags & (MDBX_RESERVE | MDBX_MULTIPLE)) &&
-                unlikely(mc->mc_dbx->md_dcmp(data, &olddata) == 0)) {
-          if (!mc->mc_xcursor)
-            /* the same data, nothing to update */
-            return MDBX_SUCCESS;
-          if (flags & MDBX_NODUPDATA)
-            return MDBX_KEYEXIST;
-          if (flags & MDBX_APPENDDUP)
-            return MDBX_EKEYMISMATCH;
-          if (likely(unsure_equal(mc->mc_dbx->md_dcmp, data, &olddata)))
-            /* data is match exactly byte-to-byte, nothing to update */
-            return MDBX_SUCCESS;
-          else {
-            /* The data has differences, but the user-provided comparator
-             * considers them equal. So continue update since called without.
-             * Continue to update since was called without MDBX_NODUPDATA. */
+          if (!(flags & (MDBX_RESERVE | MDBX_MULTIPLE)) &&
+              unlikely(mc->mc_dbx->md_dcmp(data, &olddata) == 0)) {
+            if (!mc->mc_xcursor)
+              /* the same data, nothing to update */
+              return MDBX_SUCCESS;
+            if (flags & MDBX_NODUPDATA)
+              return MDBX_KEYEXIST;
+            if (flags & MDBX_APPENDDUP)
+              return MDBX_EKEYMISMATCH;
+            if (likely(unsure_equal(mc->mc_dbx->md_dcmp, data, &olddata)))
+              /* data is match exactly byte-to-byte, nothing to update */
+              return MDBX_SUCCESS;
+            else {
+              /* The data has differences, but the user-provided comparator
+               * considers them equal. So continue update since called without.
+               * Continue to update since was called without MDBX_NODUPDATA. */
+            }
           }
-        }
       }
     } else if (unlikely(rc != MDBX_NOTFOUND))
       return rc;
@@ -14894,8 +15005,7 @@ int mdbx_cursor_put(MDBX_cursor *mc, const MDBX_val *key, MDBX_val *data,
               return err;
 
 #if MDBX_ENABLE_PGOP_STAT
-            safe64_inc(&mc->mc_txn->mt_env->me_lck->mti_pgop_stat.clone,
-                       ovpages);
+            mc->mc_txn->mt_env->me_lck->mti_pgop_stat.clone.weak += ovpages;
 #endif /* MDBX_ENABLE_PGOP_STAT */
             mdbx_cassert(mc, mdbx_dirtylist_check(mc->mc_txn));
           }
@@ -15414,7 +15524,7 @@ static struct page_result mdbx_page_new(MDBX_cursor *mc, const unsigned flags,
   mdbx_cassert(mc, *mc->mc_dbistate & DBI_DIRTY);
   mdbx_cassert(mc, mc->mc_txn->mt_flags & MDBX_TXN_DIRTY);
 #if MDBX_ENABLE_PGOP_STAT
-  safe64_inc(&mc->mc_txn->mt_env->me_lck->mti_pgop_stat.newly, npages);
+  mc->mc_txn->mt_env->me_lck->mti_pgop_stat.newly.weak += npages;
 #endif /* MDBX_ENABLE_PGOP_STAT */
 
   if (likely((flags & P_OVERFLOW) == 0)) {
@@ -16766,7 +16876,7 @@ static int mdbx_page_merge(MDBX_cursor *csrc, MDBX_cursor *cdst) {
   mdbx_cassert(cdst, cdst->mc_snum == cdst->mc_top + 1);
 
 #if MDBX_ENABLE_PGOP_STAT
-  safe64_inc(&cdst->mc_txn->mt_env->me_lck->mti_pgop_stat.merge, 1);
+  cdst->mc_txn->mt_env->me_lck->mti_pgop_stat.merge.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
 
   if (IS_LEAF(cdst->mc_pg[cdst->mc_top])) {
@@ -18262,7 +18372,7 @@ done:
         newdata->iov_base = node_data(node);
     }
 #if MDBX_ENABLE_PGOP_STAT
-    safe64_inc(&env->me_lck->mti_pgop_stat.split, 1);
+    env->me_lck->mti_pgop_stat.split.weak += 1;
 #endif /* MDBX_ENABLE_PGOP_STAT */
   }
 
@@ -19289,31 +19399,11 @@ __cold int mdbx_env_info(const MDBX_env *env, MDBX_envinfo *info,
 }
 #endif /* LIBMDBX_NO_EXPORTS_LEGACY_API */
 
-__cold int mdbx_env_info_ex(const MDBX_env *env, const MDBX_txn *txn,
-                            MDBX_envinfo *arg, size_t bytes) {
-  if (unlikely((env == NULL && txn == NULL) || arg == NULL))
-    return MDBX_EINVAL;
-
-  if (txn) {
-    int err = check_txn(txn, MDBX_TXN_BLOCKED);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-  }
-  if (env) {
-    int err = check_env(env, false);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-    if (txn && unlikely(txn->mt_env != env))
-      return MDBX_EINVAL;
-  } else {
-    env = txn->mt_env;
-  }
+__cold static int fetch_envinfo_ex(const MDBX_env *env, const MDBX_txn *txn,
+                                   MDBX_envinfo *arg, const size_t bytes) {
 
   const size_t size_before_bootid = offsetof(MDBX_envinfo, mi_bootid);
   const size_t size_before_pgop_stat = offsetof(MDBX_envinfo, mi_pgop_stat);
-  if (unlikely(bytes != sizeof(MDBX_envinfo)) && bytes != size_before_bootid &&
-      bytes != size_before_pgop_stat)
-    return MDBX_EINVAL;
 
   /* is the environment open? (https://github.com/erthink/libmdbx/issues/171) */
   if (unlikely(!env->me_map)) {
@@ -19343,64 +19433,48 @@ __cold int mdbx_env_info_ex(const MDBX_env *env, const MDBX_txn *txn,
   const MDBX_meta *const meta0 = METAPAGE(env, 0);
   const MDBX_meta *const meta1 = METAPAGE(env, 1);
   const MDBX_meta *const meta2 = METAPAGE(env, 2);
-  pgno_t unsynced_pages;
-  while (1) {
-    if (unlikely(env->me_flags & MDBX_FATAL_ERROR))
-      return MDBX_PANIC;
+  if (unlikely(env->me_flags & MDBX_FATAL_ERROR))
+    return MDBX_PANIC;
 
-    const MDBX_meta *const recent_meta = mdbx_meta_head(env);
-    arg->mi_recent_txnid = mdbx_meta_txnid_fluid(env, recent_meta);
-    arg->mi_meta0_txnid = mdbx_meta_txnid_fluid(env, meta0);
-    arg->mi_meta0_sign = unaligned_peek_u64(4, meta0->mm_datasync_sign);
-    arg->mi_meta1_txnid = mdbx_meta_txnid_fluid(env, meta1);
-    arg->mi_meta1_sign = unaligned_peek_u64(4, meta1->mm_datasync_sign);
-    arg->mi_meta2_txnid = mdbx_meta_txnid_fluid(env, meta2);
-    arg->mi_meta2_sign = unaligned_peek_u64(4, meta2->mm_datasync_sign);
-    if (likely(bytes > size_before_bootid)) {
-      memcpy(&arg->mi_bootid.meta0, &meta0->mm_bootid, 16);
-      memcpy(&arg->mi_bootid.meta1, &meta1->mm_bootid, 16);
-      memcpy(&arg->mi_bootid.meta2, &meta2->mm_bootid, 16);
-    }
-
-    const MDBX_meta *txn_meta = recent_meta;
-    arg->mi_last_pgno = txn_meta->mm_geo.next - 1;
-    arg->mi_geo.current = pgno2bytes(env, txn_meta->mm_geo.now);
-    if (txn) {
-      arg->mi_last_pgno = txn->mt_next_pgno - 1;
-      arg->mi_geo.current = pgno2bytes(env, txn->mt_end_pgno);
-
-      const txnid_t wanna_meta_txnid = (txn->mt_flags & MDBX_TXN_RDONLY)
-                                           ? txn->mt_txnid
-                                           : txn->mt_txnid - xMDBX_TXNID_STEP;
-      txn_meta = (arg->mi_meta0_txnid == wanna_meta_txnid) ? meta0 : txn_meta;
-      txn_meta = (arg->mi_meta1_txnid == wanna_meta_txnid) ? meta1 : txn_meta;
-      txn_meta = (arg->mi_meta2_txnid == wanna_meta_txnid) ? meta2 : txn_meta;
-    }
-    arg->mi_geo.lower = pgno2bytes(env, txn_meta->mm_geo.lower);
-    arg->mi_geo.upper = pgno2bytes(env, txn_meta->mm_geo.upper);
-    arg->mi_geo.shrink = pgno2bytes(env, pv2pages(txn_meta->mm_geo.shrink_pv));
-    arg->mi_geo.grow = pgno2bytes(env, pv2pages(txn_meta->mm_geo.grow_pv));
-    unsynced_pages =
-        atomic_load32(&env->me_lck->mti_unsynced_pages, mo_Relaxed) +
-        (atomic_load32(&env->me_lck->mti_meta_sync_txnid, mo_Relaxed) !=
-         (uint32_t)arg->mi_last_pgno);
-
-    arg->mi_mapsize = env->me_dxb_mmap.limit;
-    mdbx_compiler_barrier();
-    if (likely(arg->mi_meta0_txnid == mdbx_meta_txnid_fluid(env, meta0) &&
-               arg->mi_meta0_sign ==
-                   unaligned_peek_u64(4, meta0->mm_datasync_sign) &&
-               arg->mi_meta1_txnid == mdbx_meta_txnid_fluid(env, meta1) &&
-               arg->mi_meta1_sign ==
-                   unaligned_peek_u64(4, meta1->mm_datasync_sign) &&
-               arg->mi_meta2_txnid == mdbx_meta_txnid_fluid(env, meta2) &&
-               arg->mi_meta2_sign ==
-                   unaligned_peek_u64(4, meta2->mm_datasync_sign) &&
-               recent_meta == mdbx_meta_head(env) &&
-               arg->mi_recent_txnid == mdbx_meta_txnid_fluid(env, recent_meta)))
-      break;
+  const MDBX_meta *const recent_meta = mdbx_meta_head(env);
+  arg->mi_recent_txnid = mdbx_meta_txnid_fluid(env, recent_meta);
+  arg->mi_meta0_txnid = mdbx_meta_txnid_fluid(env, meta0);
+  arg->mi_meta0_sign = unaligned_peek_u64(4, meta0->mm_datasync_sign);
+  arg->mi_meta1_txnid = mdbx_meta_txnid_fluid(env, meta1);
+  arg->mi_meta1_sign = unaligned_peek_u64(4, meta1->mm_datasync_sign);
+  arg->mi_meta2_txnid = mdbx_meta_txnid_fluid(env, meta2);
+  arg->mi_meta2_sign = unaligned_peek_u64(4, meta2->mm_datasync_sign);
+  if (likely(bytes > size_before_bootid)) {
+    memcpy(&arg->mi_bootid.meta0, &meta0->mm_bootid, 16);
+    memcpy(&arg->mi_bootid.meta1, &meta1->mm_bootid, 16);
+    memcpy(&arg->mi_bootid.meta2, &meta2->mm_bootid, 16);
   }
 
+  const MDBX_meta *txn_meta = recent_meta;
+  arg->mi_last_pgno = txn_meta->mm_geo.next - 1;
+  arg->mi_geo.current = pgno2bytes(env, txn_meta->mm_geo.now);
+  if (txn) {
+    arg->mi_last_pgno = txn->mt_next_pgno - 1;
+    arg->mi_geo.current = pgno2bytes(env, txn->mt_end_pgno);
+
+    const txnid_t wanna_meta_txnid = (txn->mt_flags & MDBX_TXN_RDONLY)
+                                         ? txn->mt_txnid
+                                         : txn->mt_txnid - xMDBX_TXNID_STEP;
+    txn_meta = (arg->mi_meta0_txnid == wanna_meta_txnid) ? meta0 : txn_meta;
+    txn_meta = (arg->mi_meta1_txnid == wanna_meta_txnid) ? meta1 : txn_meta;
+    txn_meta = (arg->mi_meta2_txnid == wanna_meta_txnid) ? meta2 : txn_meta;
+  }
+  arg->mi_geo.lower = pgno2bytes(env, txn_meta->mm_geo.lower);
+  arg->mi_geo.upper = pgno2bytes(env, txn_meta->mm_geo.upper);
+  arg->mi_geo.shrink = pgno2bytes(env, pv2pages(txn_meta->mm_geo.shrink_pv));
+  arg->mi_geo.grow = pgno2bytes(env, pv2pages(txn_meta->mm_geo.grow_pv));
+  const pgno_t unsynced_pages =
+      atomic_load32(&env->me_lck->mti_unsynced_pages, mo_Relaxed) +
+      (atomic_load32(&env->me_lck->mti_meta_sync_txnid, mo_Relaxed) !=
+       (uint32_t)arg->mi_last_pgno);
+
+  arg->mi_mapsize = env->me_dxb_mmap.limit;
+
   const MDBX_lockinfo *const lck = env->me_lck;
   arg->mi_maxreaders = env->me_maxreaders;
   arg->mi_numreaders = env->me_lck_mmap.lck
@@ -19466,13 +19540,55 @@ __cold int mdbx_env_info_ex(const MDBX_env *env, const MDBX_txn *txn,
     }
   }
 
+  mdbx_compiler_barrier();
   return MDBX_SUCCESS;
 }
 
+__cold int mdbx_env_info_ex(const MDBX_env *env, const MDBX_txn *txn,
+                            MDBX_envinfo *arg, size_t bytes) {
+  if (unlikely((env == NULL && txn == NULL) || arg == NULL))
+    return MDBX_EINVAL;
+
+  if (txn) {
+    int err = check_txn(txn, MDBX_TXN_BLOCKED);
+    if (unlikely(err != MDBX_SUCCESS))
+      return err;
+  }
+  if (env) {
+    int err = check_env(env, false);
+    if (unlikely(err != MDBX_SUCCESS))
+      return err;
+    if (txn && unlikely(txn->mt_env != env))
+      return MDBX_EINVAL;
+  } else {
+    env = txn->mt_env;
+  }
+
+  const size_t size_before_bootid = offsetof(MDBX_envinfo, mi_bootid);
+  const size_t size_before_pgop_stat = offsetof(MDBX_envinfo, mi_pgop_stat);
+  if (unlikely(bytes != sizeof(MDBX_envinfo)) && bytes != size_before_bootid &&
+      bytes != size_before_pgop_stat)
+    return MDBX_EINVAL;
+
+  MDBX_envinfo snap;
+  int rc = fetch_envinfo_ex(env, txn, &snap, sizeof(snap));
+  if (unlikely(rc != MDBX_SUCCESS))
+    return rc;
+
+  while (1) {
+    rc = fetch_envinfo_ex(env, txn, arg, bytes);
+    if (unlikely(rc != MDBX_SUCCESS))
+      return rc;
+    if (likely(memcmp(&snap, arg, bytes) == 0))
+      return MDBX_SUCCESS;
+    memcpy(&snap, arg, bytes);
+  }
+}
+
 static __inline MDBX_cmp_func *get_default_keycmp(unsigned flags) {
-  return (flags & MDBX_REVERSEKEY)
-             ? cmp_reverse
-             : (flags & MDBX_INTEGERKEY) ? cmp_int_align2 : cmp_lexical;
+  return (flags & MDBX_REVERSEKEY)   ? cmp_reverse
+         : (flags & MDBX_INTEGERKEY) ? cmp_int_align2
+                                     : cmp_lexical;
 }
 
 static __inline MDBX_cmp_func *get_default_datacmp(unsigned flags) {

src/internals.h

@@ -61,13 +61,26 @@
  * Studio 2015 Update 3). But you could remove this #error and try to continue
  * at your own risk. In such case please don't rise up an issues related ONLY to
  * old compilers.
+ *
+ * NOTE:
+ *   Unfortunately, there are several different builds of "Visual Studio" that
+ *   are called "Visual Studio 2015 Update 3".
+ *
+ *   The 190024234 is used here because it is minimal version of Visual Studio
+ *   that was used for build and testing libmdbx in recent years. Soon this
+ *   value will be increased to 19.0.24241.7, since build and testing using
+ *   "Visual Studio 2015" will be performed only at https://ci.appveyor.com.
+ *
+ *   Please ask Microsoft (but not us) for information about version differences
+ *   and how to and where you can obtain the latest "Visual Studio 2015" build
+ *   with all fixes.
  */
 #error                                                                         \
     "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required."
 #endif
 #ifndef _CRT_SECURE_NO_WARNINGS
 #define _CRT_SECURE_NO_WARNINGS
-#endif
+#endif /* _CRT_SECURE_NO_WARNINGS */
 #if _MSC_VER > 1800
 #pragma warning(disable : 4464) /* relative include path contains '..' */
 #endif
@@ -264,8 +277,6 @@ static __always_inline memory_order mo_c11_load(enum MDBX_memory_order fence) {
 
 #ifndef __cplusplus
 
-static __inline void mdbx_jitter4testing(bool tiny);
-
 MDBX_MAYBE_UNUSED static __always_inline void
 mdbx_memory_fence(enum MDBX_memory_order order, bool write) {
 #ifdef MDBX_HAVE_C11ATOMICS
@@ -309,70 +320,6 @@ atomic_load32(const MDBX_atomic_uint32_t *p, enum MDBX_memory_order order) {
 #endif /* MDBX_HAVE_C11ATOMICS */
 }
 
-MDBX_MAYBE_UNUSED static __always_inline uint64_t
-atomic_store64(MDBX_atomic_uint64_t *p, const uint64_t value,
-               enum MDBX_memory_order order) {
-  STATIC_ASSERT(sizeof(MDBX_atomic_uint64_t) == 8);
-#if MDBX_64BIT_ATOMIC
-#ifdef MDBX_HAVE_C11ATOMICS
-  assert(atomic_is_lock_free(MDBX_c11a_rw(uint64_t, p)));
-  atomic_store_explicit(MDBX_c11a_rw(uint64_t, p), value, mo_c11_store(order));
-#else  /* MDBX_HAVE_C11ATOMICS */
-  if (order != mo_Relaxed)
-    mdbx_compiler_barrier();
-  p->weak = value;
-  mdbx_memory_fence(order, true);
-#endif /* MDBX_HAVE_C11ATOMICS */
-#else  /* !MDBX_64BIT_ATOMIC */
-  mdbx_compiler_barrier();
-  atomic_store32(&p->low, (uint32_t)value, mo_Relaxed);
-  mdbx_jitter4testing(true);
-  atomic_store32(&p->high, (uint32_t)(value >> 32), order);
-  mdbx_jitter4testing(true);
-#endif /* !MDBX_64BIT_ATOMIC */
-  return value;
-}
-
-MDBX_MAYBE_UNUSED static
-#if MDBX_64BIT_ATOMIC
-    __always_inline
-#endif /* MDBX_64BIT_ATOMIC */
-        uint64_t
-        atomic_load64(const MDBX_atomic_uint64_t *p,
-                      enum MDBX_memory_order order) {
-  STATIC_ASSERT(sizeof(MDBX_atomic_uint64_t) == 8);
-#if MDBX_64BIT_ATOMIC
-#ifdef MDBX_HAVE_C11ATOMICS
-  assert(atomic_is_lock_free(MDBX_c11a_ro(uint64_t, p)));
-  return atomic_load_explicit(MDBX_c11a_ro(uint64_t, p), mo_c11_load(order));
-#else  /* MDBX_HAVE_C11ATOMICS */
-  mdbx_memory_fence(order, false);
-  const uint64_t value = p->weak;
-  if (order != mo_Relaxed)
-    mdbx_compiler_barrier();
-  return value;
-#endif /* MDBX_HAVE_C11ATOMICS */
-#else  /* !MDBX_64BIT_ATOMIC */
-  mdbx_compiler_barrier();
-  uint64_t value = (uint64_t)atomic_load32(&p->high, order) << 32;
-  mdbx_jitter4testing(true);
-  value |= atomic_load32(&p->low, (order == mo_Relaxed) ? mo_Relaxed
-                                                        : mo_AcquireRelease);
-  mdbx_jitter4testing(true);
-  for (;;) {
-    mdbx_compiler_barrier();
-    uint64_t again = (uint64_t)atomic_load32(&p->high, order) << 32;
-    mdbx_jitter4testing(true);
-    again |= atomic_load32(&p->low, (order == mo_Relaxed) ? mo_Relaxed
-                                                          : mo_AcquireRelease);
-    mdbx_jitter4testing(true);
-    if (likely(value == again))
-      return value;
-    value = again;
-  }
-#endif /* !MDBX_64BIT_ATOMIC */
-}
-
 #endif /* !__cplusplus */
 
 /*----------------------------------------------------------------------------*/
@@ -384,7 +331,7 @@ MDBX_MAYBE_UNUSED static
 #define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11)
 
 /* FROZEN: The version number for a database's datafile format. */
-#define MDBX_DATA_VERSION 2
+#define MDBX_DATA_VERSION 3
 /* The version number for a database's lockfile format. */
 #define MDBX_LOCK_VERSION 4
 
@@ -488,8 +435,6 @@ typedef struct MDBX_meta {
   MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */
                             /* The size of pages used in this DB */
 #define mm_psize mm_dbs[FREE_DBI].md_xsize
-/* Any persistent environment flags, see mdbx_env */
-#define mm_flags mm_dbs[FREE_DBI].md_flags
   MDBX_canary mm_canary;
 
 #define MDBX_DATASIGN_NONE 0u
@@ -789,7 +734,11 @@ typedef struct MDBX_lockinfo {
 
 #define MDBX_DATA_MAGIC                                                        \
   ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION)
-#define MDBX_DATA_MAGIC_DEVEL ((MDBX_MAGIC << 8) + 255)
+
+#define MDBX_DATA_MAGIC_LEGACY_COMPAT                                          \
+  ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + 2)
+
+#define MDBX_DATA_MAGIC_LEGACY_DEVEL ((MDBX_MAGIC << 8) + 255)
 
 #define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION)
 
@@ -1253,6 +1202,15 @@ extern uint8_t mdbx_runtime_flags;
 extern uint8_t mdbx_loglevel;
 extern MDBX_debug_func *mdbx_debug_logger;
 
+MDBX_MAYBE_UNUSED static __inline void mdbx_jitter4testing(bool tiny) {
+#if MDBX_DEBUG
+  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
+    mdbx_osal_jitter(tiny);
+#else
+  (void)tiny;
+#endif
+}
+
 MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
     mdbx_debug_log(int level, const char *function, int line, const char *fmt,
                    ...) MDBX_PRINTF_ARGS(4, 5);
@@ -1422,15 +1380,6 @@ MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void);
 MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void);
 MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr);
 
-MDBX_MAYBE_UNUSED static __inline void mdbx_jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
-    mdbx_osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
 #endif /* !__cplusplus */
 
 #define MDBX_IS_ERROR(rc)                                                      \
@@ -1565,10 +1514,11 @@ typedef struct MDBX_node {
  *                |  1, a > b
  *                \
  */
-#if 1
+#ifndef __e2k__
 /* LY: fast enough on most systems */
 #define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
 #else
+/* LY: more parallelable on VLIW Elbrus */
 #define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
 #endif
 

src/mdbx.c++

@@ -5,9 +5,9 @@
 // Non-inline part of the libmdbx C++ API (preliminary)
 //
 
-#ifdef _MSC_VER
+#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
 #define _CRT_SECURE_NO_WARNINGS
-#endif
+#endif /* _CRT_SECURE_NO_WARNINGS */
 
 #include "../mdbx.h++"
 
@@ -992,7 +992,8 @@ bool from_base64::is_erroneous() const noexcept {
 
 template class LIBMDBX_API_TYPE buffer<legacy_allocator>;
 
-#if defined(__cpp_lib_memory_resource) && __cpp_lib_memory_resource >= 201603L
+#if defined(__cpp_lib_memory_resource) &&                                      \
+    __cpp_lib_memory_resource >= 201603L && _GLIBCXX_USE_CXX11_ABI
 template class LIBMDBX_API_TYPE buffer<polymorphic_allocator>;
 #endif /* __cpp_lib_memory_resource >= 201603L */
 
@@ -1428,7 +1429,7 @@ __cold ::std::ostream &operator<<(::std::ostream &out,
   }
 
   const auto bytes = (it.bytes < 0) ? out << "-",
-             size_t(-it.bytes) : size_t(it.bytes);
+             size_t(-it.bytes)      : size_t(it.bytes);
   struct {
     size_t one;
     const char *suffix;

src/osal.c

@@ -1461,8 +1461,9 @@ MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
   if (!NT_SUCCESS(err))
     return ntstatus2errcode(err);
 
-  SIZE_T ViewSize =
-      (flags & MDBX_RDONLY) ? 0 : mdbx_RunningUnderWine() ? size : limit;
+  SIZE_T ViewSize = (flags & MDBX_RDONLY)     ? 0
+                    : mdbx_RunningUnderWine() ? size
+                                              : limit;
   err = NtMapViewOfSection(
       map->section, GetCurrentProcess(), &map->address,
       /* ZeroBits */ 0,

src/osal.h

@@ -33,7 +33,7 @@
 #if defined(_WIN32) || defined(_WIN64)
 #if !defined(_CRT_SECURE_NO_WARNINGS)
 #define _CRT_SECURE_NO_WARNINGS
-#endif
+#endif /* _CRT_SECURE_NO_WARNINGS */
 #if !defined(_NO_CRT_STDIO_INLINE) && MDBX_BUILD_SHARED_LIBRARY &&             \
     !defined(xMDBX_TOOLS) && MDBX_WITHOUT_MSVC_CRT
 #define _NO_CRT_STDIO_INLINE
@@ -114,11 +114,9 @@
 #include <mach/mach_host.h>
 #include <mach/mach_port.h>
 #include <uuid/uuid.h>
-#undef P_DIRTY
 #endif
 
 #if defined(__linux__) || defined(__gnu_linux__)
-#include <linux/sysctl.h>
 #include <sched.h>
 #include <sys/sendfile.h>
 #include <sys/statfs.h>
@@ -481,9 +479,10 @@ typedef union MDBX_srwlock {
 } MDBX_srwlock;
 #endif /* Windows */
 
-#ifdef __cplusplus
-extern void mdbx_osal_jitter(bool tiny);
-#else
+#ifndef __cplusplus
+
+MDBX_MAYBE_UNUSED MDBX_INTERNAL_FUNC void mdbx_osal_jitter(bool tiny);
+MDBX_MAYBE_UNUSED static __inline void mdbx_jitter4testing(bool tiny);
 
 /*----------------------------------------------------------------------------*/
 /* Atomics */
@@ -735,7 +734,6 @@ MDBX_MAYBE_UNUSED static __inline uintptr_t mdbx_thread_self(void) {
   return (uintptr_t)thunk;
 }
 
-MDBX_MAYBE_UNUSED MDBX_INTERNAL_FUNC void mdbx_osal_jitter(bool tiny);
 MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void);
 MDBX_INTERNAL_FUNC uint64_t
 mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16);

test/base.h

@@ -23,7 +23,9 @@
 #define _WIN32_WINNT 0x0601 /* Windows 7 */
 #endif
 #ifdef _MSC_VER
+#ifndef _CRT_SECURE_NO_WARNINGS
 #define _CRT_SECURE_NO_WARNINGS
+#endif /* _CRT_SECURE_NO_WARNINGS */
 #pragma warning(push, 1)
 #pragma warning(disable : 4548) /* expression before comma has no effect;      \
                                    expected expression with side - effect */

test/hill.cc

@@ -73,7 +73,12 @@ bool testcase_hill::run() {
   uint64_t committed_serial = serial_count;
   unsigned txn_nops = 0;
 
-  bool rc = false;
+  bool rc = speculum_verify();
+  if (!rc) {
+    log_notice("uphill: bailout before main loop");
+    goto bailout;
+  }
+
   while (should_continue()) {
     const keygen::serial_t a_serial = serial_count;
     if (unlikely(!keyvalue_maker.increment(serial_count, 1))) {

test/test.cc

@@ -641,7 +641,8 @@ enum speculum_cursors : int {
   prev = 1,
   prev_prev = 2,
   next = 3,
-  next_next = 4
+  next_next = 4,
+  seek_check = 5
 };
 
 bool testcase::is_same(const Item &a, const Item &b) const {
@@ -715,7 +716,7 @@ void testcase::speculum_check_cursor(const char *where, const char *stage,
   // verbose(where, stage, cursor_key, cursor_data, cursor_err);
   // verbose(where, stage, it);
   if (cursor_err != MDBX_SUCCESS && cursor_err != MDBX_NOTFOUND &&
-      cursor_err != MDBX_RESULT_TRUE)
+      cursor_err != MDBX_RESULT_TRUE && cursor_err != MDBX_ENODATA)
     failure("speculum-%s: %s %s %d %s", where, stage, "cursor-get", cursor_err,
             mdbx_strerror(cursor_err));
 
@@ -852,11 +853,26 @@ int testcase::insert(const keygen::buffer &akey, const keygen::buffer &adata,
   int err;
   bool rc = true;
   Item item;
+#if SPECULUM_CURSORS
+  MDBX_cursor *check_seek_cursor = nullptr;
+  MDBX_val seek_check_key, seek_check_data;
+  int seek_check_err = 42;
+#endif /* SPECULUM_CURSORS */
   if (config.params.speculum) {
     item.first = iov2dataview(akey);
     item.second = iov2dataview(adata);
 #if SPECULUM_CURSORS
     speculum_prepare_cursors(item);
+    check_seek_cursor = speculum_cursors[seek_check].get();
+    seek_check_key = akey->value;
+    seek_check_data = adata->value;
+    seek_check_err = mdbx_cursor_get(
+        check_seek_cursor, &seek_check_key, &seek_check_data,
+        (config.params.table_flags & MDBX_DUPSORT) ? MDBX_GET_BOTH
+                                                   : MDBX_SET_KEY);
+    if (seek_check_err != MDBX_SUCCESS && seek_check_err != MDBX_NOTFOUND)
+      failure("speculum-%s: %s pre-insert %d %s", "insert", "seek",
+              seek_check_err, mdbx_strerror(seek_check_err));
 #endif /* SPECULUM_CURSORS */
   }
 
@@ -881,6 +897,26 @@ int testcase::insert(const keygen::buffer &akey, const keygen::buffer &adata,
     }
 
 #if SPECULUM_CURSORS
+    if (insertion_result.second) {
+      if (seek_check_err != MDBX_NOTFOUND) {
+        log_error(
+            "speculum.pre-insert-seek: unexpected %d {%s, %s}", seek_check_err,
+            mdbx_dump_val(&seek_check_key, dump_key, sizeof(dump_key)),
+            mdbx_dump_val(&seek_check_data, dump_value, sizeof(dump_value)));
+        rc = false;
+      }
+    } else {
+      if (seek_check_err != MDBX_SUCCESS) {
+        log_error(
+            "speculum.pre-insert-seek: unexpected %d {%s, %s}", seek_check_err,
+            mdbx_dump_val(&seek_check_key, dump_key, sizeof(dump_key)),
+            mdbx_dump_val(&seek_check_data, dump_value, sizeof(dump_value)));
+        speculum_check_iterator("insert", "pre-seek", insertion_result.first,
+                                seek_check_key, seek_check_data);
+        rc = false;
+      }
+    }
+
     if (insertion_result.first != speculum.begin()) {
       const auto cursor_prev = speculum_cursors[prev].get();
       auto it_prev = insertion_result.first;
@@ -1050,6 +1086,15 @@ bool testcase::speculum_verify() {
   MDBX_val akey, avalue;
   MDBX_val mkey, mvalue;
   err = mdbx_cursor_get(cursor, &akey, &avalue, MDBX_FIRST);
+  if (err == MDBX_NOTFOUND) {
+    err = mdbx_cursor_get(cursor, &akey, &avalue, MDBX_GET_CURRENT);
+    if (err == MDBX_ENODATA)
+      err = MDBX_NOTFOUND;
+    else {
+      log_error("unexpected %d for MDBX_GET_CURRENT on empty DB", err);
+      rc = false;
+    }
+  }
 
   unsigned extra = 0, lost = 0, n = 0;
   assert(std::is_sorted(speculum.cbegin(), speculum.cend(), ItemCompare(this)));
@@ -1128,6 +1173,13 @@ bool testcase::speculum_verify() {
       log_error("false-negative cursor-eof: %u, rc %i", n, eof);
       rc = false;
     }
+    err = mdbx_cursor_get(cursor, &akey, &avalue, MDBX_GET_CURRENT);
+    if (err == MDBX_SUCCESS)
+      err = mdbx_cursor_get(cursor, &akey, &avalue, MDBX_NEXT);
+    if (err != MDBX_ENODATA) {
+      log_error("unexpected %d for MDBX_GET_CURRENT at EOF", err);
+      rc = false;
+    }
   }
   mdbx_cursor_close(cursor);
   return rc;

test/test.h

@@ -202,7 +202,7 @@ protected:
 #define SPECULUM_CURSORS 1
 #endif /* SPECULUM_CURSORS */
 #if SPECULUM_CURSORS
-  scoped_cursor_guard speculum_cursors[5];
+  scoped_cursor_guard speculum_cursors[5 + 1];
   void speculum_prepare_cursors(const Item &item);
   void speculum_check_cursor(const char *where, const char *stage,
                              const testcase::SET::const_iterator &it,