mdbx: big-bang (initial).

- OS Abstraction Layer;
 - Windows Support.
 - preparation for more changes.

Change-Id: I53772eda9091ba361cbc9a28656190ea0d4c5cee

.clang-format

@@ -0,0 +1,3 @@
+BasedOnStyle: LLVM
+Standard: Cpp11
+ReflowComments: true

AUTHORS

@@ -0,0 +1,27 @@
+Contributors
+============
+
+Alexey Naumov <alexey.naumov@gmail.com>
+Chris Mikkelson <cmikk@qwest.net>
+Claude Brisson <claude.brisson@gmail.com>
+David Barbour <dmbarbour@gmail.com>
+David Wilson <dw@botanicus.net>
+Hallvard Furuseth <hallvard@openldap.org>, <h.b.furuseth@usit.uio.no>
+Heiko Becker <heirecka@exherbo.org>
+Howard Chu <hyc@openldap.org>, <hyc@symas.com>
+Ignacio Casal Quinteiro <ignacio.casal@nice-software.com>
+Jean-Christophe DUBOIS <jcd@tribudubois.net>
+John Hewson <john@jahewson.com>
+Kurt Zeilenga <kurt.zeilenga@isode.com>
+Leonid Yuriev <leo@yuriev.ru>, <lyuryev@ptsecurity.com>
+Lorenz Bauer <lmb@cloudflare.com>
+Luke Yeager <lyeager@nvidia.com>
+Martin Hedenfalk <martin@bzero.se>
+Ondrej Kuznik <ondrej.kuznik@acision.com>
+Orivej Desh <orivej@gmx.fr>
+Oskari Timperi <oskari.timperi@iki.fi>
+Pavel Medvedev <pmedvedev@gmail.com>
+Philipp Storz <philipp.storz@bareos.com>
+Quanah Gibson-Mount <quanah@openldap.org>
+Salvador Ortiz <sog@msg.com.mx>
+Sebastien Launay <sebastien@slaunay.fr>

Makefile

@@ -23,9 +23,9 @@ mandir	?= $(prefix)/man
 suffix	?=
 
 CC	?= gcc
-XCFLAGS	?= -DNDEBUG=1 -DMDB_DEBUG=0
+XCFLAGS	?= -DNDEBUG=1 -DMDB_DEBUG=0 -DMDBX_EXPORTS=1
-CFLAGS	?= -O2 -g3 -Wall -Werror -Wextra -ffunction-sections -fPIC
+CFLAGS	?= -O2 -g3 -Wall -Werror -Wextra -ffunction-sections -fPIC -fvisibility=hidden
-CFLAGS	+= -std=gnu99 -pthread $(XCFLAGS)
+CFLAGS	+= -D_GNU_SOURCE=1 -std=gnu99 -pthread $(XCFLAGS)
 COVER	?= -coverage -fprofile-arcs -ftest-coverage -O0
 
 # LY: for ability to built with modern glibc,
@@ -44,7 +44,7 @@ MANPAGES	:= mdbx_stat.1 mdbx_copy.1 mdbx_dump.1 mdbx_load.1
 TESTS		:= test0 test1 test2 test3 test4 test5 test6 test_bench \
 		   test_yota1 test_yota2
 
-SRC_MDBX	:= $(add_prefix src/, mdbx.c mdbx.h reopen.h barriers.h midl.h)
+MDBX_SRC	:= mdbx.h $(addprefix src/, mdbx.c osal.c lck-posix.c defs.h bits.h osal.h midl.h)
 
 .PHONY: mdbx all install clean check tests coverage
 
@@ -80,22 +80,28 @@ check:	tests
 		&& echo "*** LMDB-TEST-6" && ./test6 && ./mdbx_chk -v tmp.db \
 		&& echo "*** LMDB-TESTs - all done"
 
-mdbx.o: $(SRC_MDBX) Makefile
+mdbx.o: $(MDBX_SRC) Makefile
 	$(CC) $(CFLAGS) -c src/mdbx.c -o $@
 
-libmdbx.a:	mdbx.o
+osal.o: $(MDBX_SRC) Makefile
-	$(AR) rs $@ $^
+	$(CC) $(CFLAGS) -c src/osal.c -o $@
 
-libmdbx.so:	mdbx.o
+lck-posix.o: $(MDBX_SRC) Makefile
+	$(CC) $(CFLAGS) -c src/lck-posix.c -o $@
+
+libmdbx.a:	mdbx.o osal.o lck-posix.o
+	$(AR) rs $@ $?
+
+libmdbx.so:	mdbx.o osal.o lck-posix.o
 	$(CC) $(CFLAGS) $(LDFLAGS) -save-temps -pthread -shared $(LDOPS) -o $@ $^
 
-mdbx_%:	src/mdbx_%.c mdbx.o
+mdbx_%:	src/tools/mdbx_%.c libmdbx.a
 	$(CC) $(CFLAGS) $(LDFLAGS) $(LDOPS) -o $@ $^
 
-test%: test/test%.c mdbx.o
+test%: test/test%.c libmdbx.a
 	$(CC) $(CFLAGS) $(LDFLAGS) -Isrc -o $@ $^
 
-gcov-mdbx.o: $(SRC_MDBX) Makefile
+gcov-mdbx.o: $(MDBX_SRC) Makefile
 	$(CC) $(CFLAGS) $(COVER) -c src/mdbx.c -o $@
 
 # Seem this useless :(

mdbx.h

@@ -1,5 +1,17 @@
 /*
- * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ *
+ * ---
  *
  * This code is derived from "LMDB engine" written by
  * Howard Chu (Symas Corporation), which itself derived from btree.c
@@ -35,48 +47,140 @@
  */
 
 #pragma once
+/* *INDENT-OFF* */
+/* clang-format off */
+
 #ifndef _MDBX_H_
 #define _MDBX_H_
 #define MDBX_MODE_ENABLED 1
 
+#ifndef __has_attribute
+#	define __has_attribute(x) (0)
+#endif
+
+#ifndef __dll_export
+#	if defined(_WIN32) || defined(__CYGWIN__)
+#		if defined(__GNUC__) || __has_attribute(dllexport)
+#			define __dll_export __attribute__((dllexport))
+#		elif defined(_MSC_VER)
+#			define __dll_export __declspec(dllexport)
+#		else
+#			define __dll_export
+#		endif
+#	elif defined(__GNUC__) || __has_attribute(visibility)
+#		define __dll_export __attribute__((visibility("default")))
+#	else
+#		define __dll_export
+#	endif
+#endif /* __dll_export */
+
+#ifndef __dll_import
+#	if defined(_WIN32) || defined(__CYGWIN__)
+#		if defined(__GNUC__) || __has_attribute(dllimport)
+#			define __dll_import __attribute__((dllimport))
+#		elif defined(_MSC_VER)
+#			define __dll_import __declspec(dllimport)
+#		else
+#			define __dll_import
+#		endif
+#	else
+#		define __dll_import
+#	endif
+#endif /* __dll_import */
+
+#if defined(LIBMDBX_EXPORTS)
+#	define LIBMDBX_API __dll_export
+#elif defined(MDBX_IMPORTS)
+#	define LIBMDBX_API __dll_import
+#else
+#	define LIBMDBX_API
+#endif /* LIBMDBX_API */
+
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable : 4514) /* 'xyz': unreferenced inline function  \
+                                   has been removed */
+#pragma warning(disable : 4710) /* 'xyz': function not inlined */
+#pragma warning(disable : 4711) /* function 'xyz' selected for          \
+                                   automatic inline expansion */
+#pragma warning(disable : 4061) /* enumerator 'abc' in switch of enum   \
+                                   'xyz' is not explicitly handled by a case   \
+                                   label */
+#pragma warning(disable : 4201) /* nonstandard extension used :         \
+                                   nameless struct / union */
+#pragma warning(disable : 4127) /* conditional expression is constant   \
+                                   */
+
+#pragma warning(push, 1)
+#pragma warning(disable : 4530) /* C++ exception handler used, but      \
+                                    unwind semantics are not enabled. Specify  \
+                                    /EHsc */
+#pragma warning(disable : 4577) /* 'noexcept' used with no exception    \
+                                    handling mode specified; termination on    \
+                                    exception is not guaranteed. Specify /EHsc \
+                                    */
+#endif                          /* _MSC_VER (warnings) */
+
 #include <stdarg.h>
+#include <stddef.h>
 #include <stdint.h>
-#include <sys/types.h>
+
-#include <sys/uio.h>
+#if defined(_WIN32) || defined(_WIN64)
-#include <unistd.h>
+#	include <windows.h>
+#	include <winnt.h>
+	typedef unsigned mode_t;
+	typedef HANDLE mdbx_filehandle_t;
+	typedef DWORD mdbx_pid_t;
+	typedef DWORD mdbx_tid_t;
+#else
+#	include <pthread.h> /* for pthread_t */
+#	include <sys/uio.h> /* for truct iovec */
+#	include <sys/types.h> /* for pid_t */
+#	define HAVE_STRUCT_IOVEC 1
+	typedef int mdbx_filehandle_t;
+	typedef pid_t mdbx_pid_t;
+	typedef pthread_t mdbx_tid_t;
+#endif
+
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
+/* *INDENT-ON* */
+/* clang-format on */
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 /** Library major version */
-#define MDB_VERSION_MAJOR 0
+#define MDBX_VERSION_MAJOR 0
 /** Library minor version */
-#define MDB_VERSION_MINOR 9
+#define MDBX_VERSION_MINOR 2
 /** Library patch version */
-#define MDB_VERSION_PATCH 19
+#define MDBX_VERSION_PATCH 0
 
 /** Combine args a,b,c into a single integer for easy version comparisons */
 #define MDB_VERINT(a, b, c) (((a) << 24) | ((b) << 16) | (c))
 
 /** The full library version as a single integer */
-#define MDB_VERSION_FULL                                                       \
+#define MDBX_VERSION_FULL                                                      \
-  MDB_VERINT(MDB_VERSION_MAJOR, MDB_VERSION_MINOR, MDB_VERSION_PATCH)
+  MDB_VERINT(MDBX_VERSION_MAJOR, MDBX_VERSION_MINOR, MDBX_VERSION_PATCH)
 
 /* The release date of this library version */
-#define MDB_VERSION_DATE "DEVEL"
+#define MDBX_VERSION_DATE "DEVEL"
 
 /* A stringifier for the version info */
-#define MDB_VERSTR(a, b, c, d)                                                 \
+#define MDBX_VERSTR(a, b, c, d)                                                \
   "MDBX " #a "." #b "." #c ": (" d ", https://github.com/ReOpen/libmdbx)"
 
 /* A helper for the stringifier macro */
-#define MDB_VERFOO(a, b, c, d) MDB_VERSTR(a, b, c, d)
+#define MDBX_VERFOO(a, b, c, d) MDBX_VERSTR(a, b, c, d)
 
 /* The full library version as a C string */
-#define MDB_VERSION_STRING                                                     \
+#define MDBX_VERSION_STRING                                                    \
-  MDB_VERFOO(MDB_VERSION_MAJOR, MDB_VERSION_MINOR, MDB_VERSION_PATCH,          \
+  MDBX_VERFOO(MDBX_VERSION_MAJOR, MDBX_VERSION_MINOR, MDBX_VERSION_PATCH,      \
-             MDB_VERSION_DATE)
+              MDBX_VERSION_DATE)
 
 /* Opaque structure for a database environment.
  *
@@ -109,6 +213,14 @@ typedef struct MDB_cursor MDB_cursor;
  * The same applies to data sizes in databases with the MDB_DUPSORT flag.
  * Other data items can in theory be from 0 to 0xffffffff bytes long.
  */
+#ifndef HAVE_STRUCT_IOVEC
+struct iovec {
+  void *iov_base;
+  size_t iov_len;
+};
+#define HAVE_STRUCT_IOVEC
+#endif /* HAVE_STRUCT_IOVEC */
+
 typedef struct iovec MDB_val;
 #define mv_size iov_len
 #define mv_data iov_base
@@ -117,87 +229,85 @@ typedef struct iovec MDB_val;
 typedef int(MDB_cmp_func)(const MDB_val *a, const MDB_val *b);
 
 /* Environment Flags */
-/* mmap at a fixed address (experimental) */
-#define MDB_FIXEDMAP 0x01
 /* no environment directory */
-#define MDB_NOSUBDIR 0x4000
+#define MDB_NOSUBDIR 0x4000u
 /* don't fsync after commit */
-#define MDB_NOSYNC 0x10000
+#define MDB_NOSYNC 0x10000u
 /* read only */
-#define MDB_RDONLY 0x20000
+#define MDB_RDONLY 0x20000u
 /* don't fsync metapage after commit */
-#define MDB_NOMETASYNC 0x40000
+#define MDB_NOMETASYNC 0x40000u
 /* use writable mmap */
-#define MDB_WRITEMAP 0x80000
+#define MDB_WRITEMAP 0x80000u
 /* use asynchronous msync when MDB_WRITEMAP is used */
-#define MDB_MAPASYNC 0x100000
+#define MDB_MAPASYNC 0x100000u
 /* tie reader locktable slots to MDB_txn objects instead of to threads */
-#define MDB_NOTLS 0x200000
+#define MDB_NOTLS 0x200000u
 /* don't do any locking, caller must manage their own locks
  * WARNING: libmdbx don't support this mode. */
-#define MDB_NOLOCK__UNSUPPORTED 0x400000
+#define MDB_NOLOCK__UNSUPPORTED 0x400000u
 /* don't do readahead */
-#define MDB_NORDAHEAD 0x800000
+#define MDB_NORDAHEAD 0x800000u
 /* don't initialize malloc'd memory before writing to datafile */
-#define MDB_NOMEMINIT 0x1000000
+#define MDB_NOMEMINIT 0x1000000u
 
 #if MDBX_MODE_ENABLED
 /* aim to coalesce FreeDB records */
-#define MDBX_COALESCE 0x2000000
+#define MDBX_COALESCE 0x2000000u
 /* LIFO policy for reclaiming FreeDB records */
-#define MDBX_LIFORECLAIM 0x4000000
+#define MDBX_LIFORECLAIM 0x4000000u
 #endif /* MDBX_MODE_ENABLED */
 
 /* make a steady-sync only on close and explicit env-sync */
 #define MDBX_UTTERLY_NOSYNC (MDB_NOSYNC | MDB_MAPASYNC)
 /* debuging option, fill/perturb released pages */
-#define MDBX_PAGEPERTURB 0x8000000
+#define MDBX_PAGEPERTURB 0x8000000u
 
 /* Database Flags */
 /* use reverse string keys */
-#define MDB_REVERSEKEY 0x02
+#define MDB_REVERSEKEY 0x02u
 /* use sorted duplicates */
-#define MDB_DUPSORT 0x04
+#define MDB_DUPSORT 0x04u
 /* numeric keys in native byte order, either unsigned int or mdbx_size_t.
  *	(lmdb expects 32-bit int <= size_t <= 32/64-bit mdbx_size_t.)
  *  The keys must all be of the same size. */
-#define MDB_INTEGERKEY 0x08
+#define MDB_INTEGERKEY 0x08u
 /* with MDB_DUPSORT, sorted dup items have fixed size */
-#define MDB_DUPFIXED 0x10
+#define MDB_DUPFIXED 0x10u
 /* with MDB_DUPSORT, dups are MDB_INTEGERKEY-style integers */
-#define MDB_INTEGERDUP 0x20
+#define MDB_INTEGERDUP 0x20u
 /* with MDB_DUPSORT, use reverse string dups */
-#define MDB_REVERSEDUP 0x40
+#define MDB_REVERSEDUP 0x40u
 /* create DB if not already existing */
-#define MDB_CREATE 0x40000
+#define MDB_CREATE 0x40000u
 
 /* Write Flags */
 /* For put: Don't write if the key already exists. */
-#define MDB_NOOVERWRITE 0x10
+#define MDB_NOOVERWRITE 0x10u
 /* Only for MDB_DUPSORT
  * For put: don't write if the key and data pair already exist.
  * For mdbx_cursor_del: remove all duplicate data items.
  */
-#define MDB_NODUPDATA 0x20
+#define MDB_NODUPDATA 0x20u
 /* For mdbx_cursor_put: overwrite the current key/data pair
  *  MDBX allows this flag for mdbx_put() for explicit overwrite/update without
  * insertion. */
-#define MDB_CURRENT 0x40
+#define MDB_CURRENT 0x40u
 /* For put: Just reserve space for data, don't copy it. Return a
  * pointer to the reserved space.
  */
-#define MDB_RESERVE 0x10000
+#define MDB_RESERVE 0x10000u
 /* Data is being appended, don't split full pages. */
-#define MDB_APPEND 0x20000
+#define MDB_APPEND 0x20000u
 /* Duplicate data is being appended, don't split full pages. */
-#define MDB_APPENDDUP 0x40000
+#define MDB_APPENDDUP 0x40000u
 /* Store multiple data items in one call. Only for MDB_DUPFIXED. */
-#define MDB_MULTIPLE 0x80000
+#define MDB_MULTIPLE 0x80000u
 
 /* Copy Flags */
 /* Compacting copy: Omit free space from copy, and renumber all
  * pages sequentially. */
-#define MDB_CP_COMPACT 1
+#define MDB_CP_COMPACT 1u
 
 /* Cursor Get operations.
  *
@@ -280,7 +390,8 @@ typedef enum MDB_cursor_op {
 #define MDB_MAP_RESIZED (-30785)
 /* Operation and DB incompatible, or DB type changed. This can mean:
  *	 - The operation expects an MDB_DUPSORT / MDB_DUPFIXED database.
- *	 - Opening a named DB when the unnamed DB has MDB_DUPSORT/MDB_INTEGERKEY.
+ *	 - Opening a named DB when the unnamed DB has
+ *MDB_DUPSORT/MDB_INTEGERKEY.
  *	 - Accessing a data record as a database, or vice versa.
  *	 - The database was dropped and recreated with different flags.
  */
@@ -307,7 +418,6 @@ typedef enum MDB_cursor_op {
  *  - ABI version mismatch (rare case); */
 #define MDBX_EBADSIGN (-30420)
 
-
 /* Statistics for a database in the environment */
 typedef struct MDBX_stat {
   unsigned ms_psize;        /* Size of a database page.
@@ -325,12 +435,12 @@ typedef struct MDBX_envinfo {
   void *me_mapaddr;       /* Address of map, if fixed */
   size_t me_mapsize;      /* Size of the data memory map */
   size_t me_last_pgno;    /* ID of the last used page */
-  size_t me_last_txnid;   /* ID of the last committed transaction */
+  uint64_t me_last_txnid; /* ID of the last committed transaction */
   unsigned me_maxreaders; /* max reader slots in the environment */
   unsigned me_numreaders; /* max reader slots used in the environment */
-  size_t me_tail_txnid;   /* ID of the last reader transaction */
+  uint64_t me_tail_txnid; /* ID of the last reader transaction */
-  size_t me_meta1_txnid, me_meta1_sign;
+  uint64_t me_meta1_txnid, me_meta1_sign;
-  size_t me_meta2_txnid, me_meta2_sign;
+  uint64_t me_meta2_txnid, me_meta2_sign;
 } MDBX_envinfo;
 
 /* Return the LMDB library version information.
@@ -343,7 +453,7 @@ typedef struct MDBX_envinfo {
  * here
  * Returns "version string" The library version as a string
  */
-const char *mdbx_version(int *major, int *minor, int *patch);
+LIBMDBX_API const char *mdbx_version(int *major, int *minor, int *patch);
 
 /* Return a string describing a given error code.
  *
@@ -355,8 +465,8 @@ const char *mdbx_version(int *major, int *minor, int *patch);
  * [in] err The error code
  * Returns "error message" The description of the error
  */
-const char *mdbx_strerror(int errnum);
+LIBMDBX_API const char *mdbx_strerror(int errnum);
-const char *mdbx_strerror_r(int errnum, char *buf, size_t buflen);
+LIBMDBX_API const char *mdbx_strerror_r(int errnum, char *buf, size_t buflen);
 
 /* Create an LMDB environment handle.
  *
@@ -370,7 +480,7 @@ const char *mdbx_strerror_r(int errnum, char *buf, size_t buflen);
  * [out] env The address where the new handle will be stored
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_env_create(MDB_env **env);
+LIBMDBX_API int mdbx_env_create(MDB_env **env);
 
 /* Open an environment handle.
  *
@@ -383,19 +493,6 @@ int mdbx_env_create(MDB_env **env);
  * must be set to 0 or by bitwise OR'ing together one or more of the
  * values described here.
  * Flags set by mdbx_env_set_flags() are also used.
- *	 - MDB_FIXEDMAP
- *      use a fixed address for the mmap region. This flag must be specified
- *      when creating the environment, and is stored persistently in the
- *environment.
- *		If successful, the memory map will always reside at the same
- *virtual address
- *		and pointers used to reference data items in the database will
- *be constant
- *		across multiple invocations. This option may not always work,
- *depending on
- *		how the operating system has allocated memory to shared
- *libraries and other uses.
- *		The feature is highly experimental.
  *	 - MDB_NOSUBDIR
  *		By default, LMDB creates its environment in a directory whose
  *		pathname is given in \b path, and creates its data and lock
@@ -558,8 +655,9 @@ int mdbx_env_create(MDB_env **env);
  *files.
  *	 - EAGAIN - the environment was locked by another process.
  */
-int mdbx_env_open(MDB_env *env, const char *path, unsigned flags, mode_t mode);
+LIBMDBX_API int mdbx_env_open(MDB_env *env, const char *path, unsigned flags,
-int mdbx_env_open_ex(MDB_env *env, const char *path, unsigned flags,
+                              mode_t mode);
+LIBMDBX_API int mdbx_env_open_ex(MDB_env *env, const char *path, unsigned flags,
                                  mode_t mode, int *exclusive);
 
 /* Copy an LMDB environment to the specified path.
@@ -576,7 +674,7 @@ int mdbx_env_open_ex(MDB_env *env, const char *path, unsigned flags,
  * empty.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_env_copy(MDB_env *env, const char *path);
+LIBMDBX_API int mdbx_env_copy(MDB_env *env, const char *path);
 
 /* Copy an LMDB environment to the specified file descriptor.
  *
@@ -591,7 +689,7 @@ int mdbx_env_copy(MDB_env *env, const char *path);
  * have already been opened for Write access.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_env_copyfd(MDB_env *env, int fd);
+LIBMDBX_API int mdbx_env_copyfd(MDB_env *env, mdbx_filehandle_t fd);
 
 /* Copy an LMDB environment to the specified path, with options.
  *
@@ -616,7 +714,7 @@ int mdbx_env_copyfd(MDB_env *env, int fd);
  *leak.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_env_copy2(MDB_env *env, const char *path, unsigned flags);
+LIBMDBX_API int mdbx_env_copy2(MDB_env *env, const char *path, unsigned flags);
 
 /* Copy an LMDB environment to the specified file descriptor,
  *	with options.
@@ -635,7 +733,8 @@ int mdbx_env_copy2(MDB_env *env, const char *path, unsigned flags);
  * See mdbx_env_copy2() for options.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_env_copyfd2(MDB_env *env, int fd, unsigned flags);
+LIBMDBX_API int mdbx_env_copyfd2(MDB_env *env, mdbx_filehandle_t fd,
+                                 unsigned flags);
 
 /* Return statistics about the LMDB environment.
  *
@@ -643,7 +742,7 @@ int mdbx_env_copyfd2(MDB_env *env, int fd, unsigned flags);
  * [out] stat The address of an MDB_stat structure
  * 	where the statistics will be copied
  */
-int mdbx_env_stat(MDB_env *env, MDBX_stat *stat, size_t bytes);
+LIBMDBX_API int mdbx_env_stat(MDB_env *env, MDBX_stat *stat, size_t bytes);
 
 /* Return information about the LMDB environment.
  *
@@ -651,7 +750,7 @@ int mdbx_env_stat(MDB_env *env, MDBX_stat *stat, size_t bytes);
  * [out] stat The address of an MDB_envinfo structure
  * 	where the information will be copied
  */
-int mdbx_env_info(MDB_env *env, MDBX_envinfo *info, size_t bytes);
+LIBMDBX_API int mdbx_env_info(MDB_env *env, MDBX_envinfo *info, size_t bytes);
 
 /* Flush the data buffers to disk.
  *
@@ -670,7 +769,7 @@ int mdbx_env_info(MDB_env *env, MDBX_envinfo *info, size_t bytes);
  *	 - EINVAL - an invalid parameter was specified.
  *	 - EIO - an error occurred during synchronization.
  */
-int mdbx_env_sync(MDB_env *env, int force);
+LIBMDBX_API int mdbx_env_sync(MDB_env *env, int force);
 
 /* Close the environment and release the memory map.
  *
@@ -687,7 +786,7 @@ int mdbx_env_sync(MDB_env *env, int force);
  *  on opening next time, and transactions since the last non-weak
  *  checkpoint (meta-page update) will rolledback for consistency guarantee.
  */
-void mdbx_env_close(MDB_env *env);
+LIBMDBX_API void mdbx_env_close(MDB_env *env);
 
 /* Set environment flags.
  *
@@ -701,7 +800,7 @@ void mdbx_env_close(MDB_env *env);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_env_set_flags(MDB_env *env, unsigned flags, int onoff);
+LIBMDBX_API int mdbx_env_set_flags(MDB_env *env, unsigned flags, int onoff);
 
 /* Get environment flags.
  *
@@ -711,7 +810,7 @@ int mdbx_env_set_flags(MDB_env *env, unsigned flags, int onoff);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_env_get_flags(MDB_env *env, unsigned *flags);
+LIBMDBX_API int mdbx_env_get_flags(MDB_env *env, unsigned *flags);
 
 /* Return the path that was used in mdbx_env_open().
  *
@@ -723,7 +822,7 @@ int mdbx_env_get_flags(MDB_env *env, unsigned *flags);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_env_get_path(MDB_env *env, const char **path);
+LIBMDBX_API int mdbx_env_get_path(MDB_env *env, const char **path);
 
 /* Return the filedescriptor for the given environment.
  *
@@ -737,7 +836,7 @@ int mdbx_env_get_path(MDB_env *env, const char **path);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_env_get_fd(MDB_env *env, int *fd);
+LIBMDBX_API int mdbx_env_get_fd(MDB_env *env, mdbx_filehandle_t *fd);
 
 /* Set the size of the memory map to use for this environment.
  *
@@ -772,7 +871,7 @@ int mdbx_env_get_fd(MDB_env *env, int *fd);
  *has
  *   	an active write transaction.
  */
-int mdbx_env_set_mapsize(MDB_env *env, size_t size);
+LIBMDBX_API int mdbx_env_set_mapsize(MDB_env *env, size_t size);
 
 /* Set the maximum number of threads/reader slots for the environment.
  *
@@ -792,7 +891,7 @@ int mdbx_env_set_mapsize(MDB_env *env, size_t size);
  *	 - EINVAL - an invalid parameter was specified, or the environment is
  *already open.
  */
-int mdbx_env_set_maxreaders(MDB_env *env, unsigned readers);
+LIBMDBX_API int mdbx_env_set_maxreaders(MDB_env *env, unsigned readers);
 
 /* Get the maximum number of threads/reader slots for the environment.
  *
@@ -802,7 +901,7 @@ int mdbx_env_set_maxreaders(MDB_env *env, unsigned readers);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_env_get_maxreaders(MDB_env *env, unsigned *readers);
+LIBMDBX_API int mdbx_env_get_maxreaders(MDB_env *env, unsigned *readers);
 
 /* Set the maximum number of named databases for the environment.
  *
@@ -822,7 +921,7 @@ int mdbx_env_get_maxreaders(MDB_env *env, unsigned *readers);
  *	 - EINVAL - an invalid parameter was specified, or the environment is
  *already open.
  */
-int mdbx_env_set_maxdbs(MDB_env *env, MDB_dbi dbs);
+LIBMDBX_API int mdbx_env_set_maxdbs(MDB_env *env, MDB_dbi dbs);
 
 /* Get the maximum size of keys and MDB_DUPSORT data we can write.
  *
@@ -831,7 +930,7 @@ int mdbx_env_set_maxdbs(MDB_env *env, MDB_dbi dbs);
  * [in] env An environment handle returned by mdbx_env_create()
  * Returns The maximum size of a key we can write
  */
-int mdbx_env_get_maxkeysize(MDB_env *env);
+LIBMDBX_API int mdbx_env_get_maxkeysize(MDB_env *env);
 
 /* Set application information associated with the MDB_env.
  *
@@ -839,14 +938,14 @@ int mdbx_env_get_maxkeysize(MDB_env *env);
  * [in] ctx An arbitrary pointer for whatever the application needs.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_env_set_userctx(MDB_env *env, void *ctx);
+LIBMDBX_API int mdbx_env_set_userctx(MDB_env *env, void *ctx);
 
 /* Get the application information associated with the MDB_env.
  *
  * [in] env An environment handle returned by mdbx_env_create()
  * Returns The pointer set by mdbx_env_set_userctx().
  */
-void *mdbx_env_get_userctx(MDB_env *env);
+LIBMDBX_API void *mdbx_env_get_userctx(MDB_env *env);
 
 /* A callback function for most LMDB assert() failures,
  * called before printing the message and aborting.
@@ -864,7 +963,7 @@ typedef void MDB_assert_func(MDB_env *env, const char *msg,
  * [in] func An MDB_assert_func function, or 0.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_env_set_assert(MDB_env *env, MDB_assert_func *func);
+LIBMDBX_API int mdbx_env_set_assert(MDB_env *env, MDB_assert_func *func);
 
 /* Create a transaction for use with the environment.
  *
@@ -898,14 +997,14 @@ int mdbx_env_set_assert(MDB_env *env, MDB_assert_func *func);
  *		the reader lock table is full. See mdbx_env_set_maxreaders().
  *	 - ENOMEM - out of memory.
  */
-int mdbx_txn_begin(MDB_env *env, MDB_txn *parent, unsigned flags,
+LIBMDBX_API int mdbx_txn_begin(MDB_env *env, MDB_txn *parent, unsigned flags,
                                MDB_txn **txn);
 
 /* Returns the transaction's MDB_env
  *
  * [in] txn A transaction handle returned by mdbx_txn_begin()
  */
-MDB_env *mdbx_txn_env(MDB_txn *txn);
+LIBMDBX_API MDB_env *mdbx_txn_env(MDB_txn *txn);
 
 /* Return the transaction's ID.
  *
@@ -916,7 +1015,7 @@ MDB_env *mdbx_txn_env(MDB_txn *txn);
  * [in] txn A transaction handle returned by mdbx_txn_begin()
  * Returns A transaction ID, valid if input is an active transaction.
  */
-size_t mdbx_txn_id(MDB_txn *txn);
+LIBMDBX_API size_t mdbx_txn_id(MDB_txn *txn);
 
 /* Commit all the operations of a transaction into the database.
  *
@@ -940,7 +1039,7 @@ size_t mdbx_txn_id(MDB_txn *txn);
  *	 - EIO - a low-level I/O error occurred while writing.
  *	 - ENOMEM - out of memory.
  */
-int mdbx_txn_commit(MDB_txn *txn);
+LIBMDBX_API int mdbx_txn_commit(MDB_txn *txn);
 
 /* Abandon all the operations of the transaction instead of saving
  * them.
@@ -959,7 +1058,7 @@ int mdbx_txn_commit(MDB_txn *txn);
  *
  * [in] txn A transaction handle returned by mdbx_txn_begin()
  */
-int mdbx_txn_abort(MDB_txn *txn);
+LIBMDBX_API int mdbx_txn_abort(MDB_txn *txn);
 
 /* Reset a read-only transaction.
  *
@@ -978,7 +1077,7 @@ int mdbx_txn_abort(MDB_txn *txn);
  * the database size may grow much more rapidly than otherwise.
  * [in] txn A transaction handle returned by mdbx_txn_begin()
  */
-int mdbx_txn_reset(MDB_txn *txn);
+LIBMDBX_API int mdbx_txn_reset(MDB_txn *txn);
 
 /* Renew a read-only transaction.
  *
@@ -992,7 +1091,7 @@ int mdbx_txn_reset(MDB_txn *txn);
  *		must be shut down.
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_txn_renew(MDB_txn *txn);
+LIBMDBX_API int mdbx_txn_renew(MDB_txn *txn);
 
 /* Open a database in the environment.
  * A database handle denotes the name and parameters of a database,
@@ -1072,7 +1171,8 @@ int mdbx_txn_renew(MDB_txn *txn);
  *	 - MDB_DBS_FULL - too many databases have been opened. See
  *mdbx_env_set_maxdbs().
  */
-int mdbx_dbi_open(MDB_txn *txn, const char *name, unsigned flags, MDB_dbi *dbi);
+LIBMDBX_API int mdbx_dbi_open(MDB_txn *txn, const char *name, unsigned flags,
+                              MDB_dbi *dbi);
 
 /* Retrieve statistics for a database.
  *
@@ -1084,7 +1184,8 @@ int mdbx_dbi_open(MDB_txn *txn, const char *name, unsigned flags, MDB_dbi *dbi);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_stat(MDB_txn *txn, MDB_dbi dbi, MDBX_stat *stat, size_t bytes);
+LIBMDBX_API int mdbx_stat(MDB_txn *txn, MDB_dbi dbi, MDBX_stat *stat,
+                          size_t bytes);
 
 /* Retrieve the DB flags for a database handle.
  *
@@ -1093,7 +1194,7 @@ int mdbx_stat(MDB_txn *txn, MDB_dbi dbi, MDBX_stat *stat, size_t bytes);
  * [out] flags Address where the flags will be returned.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_dbi_flags(MDB_txn *txn, MDB_dbi dbi, unsigned *flags);
+LIBMDBX_API int mdbx_dbi_flags(MDB_txn *txn, MDB_dbi dbi, unsigned *flags);
 
 /* Close a database handle. Normally unnecessary. Use with care:
  *
@@ -1111,7 +1212,7 @@ int mdbx_dbi_flags(MDB_txn *txn, MDB_dbi dbi, unsigned *flags);
  * [in] env An environment handle returned by mdbx_env_create()
  * [in] dbi A database handle returned by mdbx_dbi_open()
  */
-void mdbx_dbi_close(MDB_env *env, MDB_dbi dbi);
+LIBMDBX_API void mdbx_dbi_close(MDB_env *env, MDB_dbi dbi);
 
 /* Empty or delete+close a database.
  *
@@ -1122,7 +1223,7 @@ void mdbx_dbi_close(MDB_env *env, MDB_dbi dbi);
  * environment and close the DB handle.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_drop(MDB_txn *txn, MDB_dbi dbi, int del);
+LIBMDBX_API int mdbx_drop(MDB_txn *txn, MDB_dbi dbi, int del);
 
 /* Set a custom key comparison function for a database.
  *
@@ -1146,7 +1247,7 @@ int mdbx_drop(MDB_txn *txn, MDB_dbi dbi, int del);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
+LIBMDBX_API int mdbx_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
 
 /* Set a custom data comparison function for a MDB_DUPSORT database.
  *
@@ -1174,7 +1275,7 @@ int mdbx_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
+LIBMDBX_API int mdbx_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
 
 /* Get items from a database.
  *
@@ -1200,7 +1301,8 @@ int mdbx_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
  *	 - MDB_NOTFOUND - the key was not in the database.
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_get(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data);
+LIBMDBX_API int mdbx_get(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
+                         MDB_val *data);
 
 /* Store items into a database.
  *
@@ -1252,7 +1354,7 @@ int mdbx_get(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data);
  *	 - EACCES - an attempt was made to write in a read-only transaction.
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_put(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data,
+LIBMDBX_API int mdbx_put(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data,
                          unsigned flags);
 
 /* Delete items from a database.
@@ -1283,7 +1385,8 @@ int mdbx_put(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data,
  *	 - EACCES - an attempt was made to write in a read-only transaction.
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_del(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data);
+LIBMDBX_API int mdbx_del(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
+                         MDB_val *data);
 
 /* Create a cursor handle.
  *
@@ -1313,7 +1416,8 @@ int mdbx_del(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **cursor);
+LIBMDBX_API int mdbx_cursor_open(MDB_txn *txn, MDB_dbi dbi,
+                                 MDB_cursor **cursor);
 
 /* Close a cursor handle.
  *
@@ -1321,7 +1425,7 @@ int mdbx_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **cursor);
  * Its transaction must still be live if it is a write-transaction.
  * [in] cursor A cursor handle returned by mdbx_cursor_open()
  */
-void mdbx_cursor_close(MDB_cursor *cursor);
+LIBMDBX_API void mdbx_cursor_close(MDB_cursor *cursor);
 
 /* Renew a cursor handle.
  *
@@ -1337,19 +1441,19 @@ void mdbx_cursor_close(MDB_cursor *cursor);
  * errors are:
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_cursor_renew(MDB_txn *txn, MDB_cursor *cursor);
+LIBMDBX_API int mdbx_cursor_renew(MDB_txn *txn, MDB_cursor *cursor);
 
 /* Return the cursor's transaction handle.
  *
  * [in] cursor A cursor handle returned by mdbx_cursor_open()
  */
-MDB_txn *mdbx_cursor_txn(MDB_cursor *cursor);
+LIBMDBX_API MDB_txn *mdbx_cursor_txn(MDB_cursor *cursor);
 
 /* Return the cursor's database handle.
  *
  * [in] cursor A cursor handle returned by mdbx_cursor_open()
  */
-MDB_dbi mdbx_cursor_dbi(MDB_cursor *cursor);
+LIBMDBX_API MDB_dbi mdbx_cursor_dbi(MDB_cursor *cursor);
 
 /* Retrieve by cursor.
  *
@@ -1371,7 +1475,7 @@ MDB_dbi mdbx_cursor_dbi(MDB_cursor *cursor);
  *	 - MDB_NOTFOUND - no matching key found.
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
+LIBMDBX_API int mdbx_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
                                 MDB_cursor_op op);
 
 /* Store by cursor.
@@ -1444,7 +1548,7 @@ int mdbx_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
  *	 - EACCES - an attempt was made to write in a read-only transaction.
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_cursor_put(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
+LIBMDBX_API int mdbx_cursor_put(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
                                 unsigned flags);
 
 /* Delete current key/data pair
@@ -1461,7 +1565,7 @@ int mdbx_cursor_put(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
  *	 - EACCES - an attempt was made to write in a read-only transaction.
  *	 - EINVAL - an invalid parameter was specified.
  */
-int mdbx_cursor_del(MDB_cursor *cursor, unsigned flags);
+LIBMDBX_API int mdbx_cursor_del(MDB_cursor *cursor, unsigned flags);
 
 /* Return count of duplicates for current key.
  *
@@ -1474,7 +1578,7 @@ int mdbx_cursor_del(MDB_cursor *cursor, unsigned flags);
  *	 - EINVAL - cursor is not initialized, or an invalid parameter was
  *specified.
  */
-int mdbx_cursor_count(MDB_cursor *cursor, size_t *countp);
+LIBMDBX_API int mdbx_cursor_count(MDB_cursor *cursor, size_t *countp);
 
 /* Compare two data items according to a particular database.
  *
@@ -1486,7 +1590,8 @@ int mdbx_cursor_count(MDB_cursor *cursor, size_t *countp);
  * [in] b The second item to compare
  * Returns < 0 if a < b, 0 if a == b, > 0 if a > b
  */
-int mdbx_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b);
+LIBMDBX_API int mdbx_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a,
+                         const MDB_val *b);
 
 /* Compare two data items according to a particular database.
  *
@@ -1498,7 +1603,8 @@ int mdbx_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b);
  * [in] b The second item to compare
  * Returns < 0 if a < b, 0 if a == b, > 0 if a > b
  */
-int mdbx_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b);
+LIBMDBX_API int mdbx_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a,
+                          const MDB_val *b);
 
 /* A callback function used to print a message from the library.
  *
@@ -1515,7 +1621,7 @@ typedef int(MDB_msg_func)(const char *msg, void *ctx);
  * [in] ctx Anything the message function needs
  * Returns < 0 on failure, >= 0 on success.
  */
-int mdbx_reader_list(MDB_env *env, MDB_msg_func *func, void *ctx);
+LIBMDBX_API int mdbx_reader_list(MDB_env *env, MDB_msg_func *func, void *ctx);
 
 /* Check for stale entries in the reader lock table.
  *
@@ -1523,11 +1629,11 @@ int mdbx_reader_list(MDB_env *env, MDB_msg_func *func, void *ctx);
  * [out] dead Number of stale slots that were cleared
  * Returns 0 on success, non-zero on failure.
  */
-int mdbx_reader_check(MDB_env *env, int *dead);
+LIBMDBX_API int mdbx_reader_check(MDB_env *env, int *dead);
 
-char *mdbx_dkey(MDB_val *key, char *buf);
+LIBMDBX_API char *mdbx_dkey(MDB_val *key, char *buf);
 
-int mdbx_env_close_ex(MDB_env *env, int dont_sync);
+LIBMDBX_API int mdbx_env_close_ex(MDB_env *env, int dont_sync);
 
 /* Set threshold to force flush the data buffers to disk,
  * even of MDB_NOSYNC, MDB_NOMETASYNC and MDB_MAPASYNC flags
@@ -1546,7 +1652,8 @@ int mdbx_env_close_ex(MDB_env *env, int dont_sync);
  * when a synchronous flush would be made.
  * Returns A non-zero error value on failure and 0 on success.
  */
-int mdbx_env_set_syncbytes(MDB_env *env, size_t bytes);
+LIBMDBX_API int mdbx_env_set_syncbytes(MDB_env *env, size_t bytes);
+
 /* Returns a lag of the reading.
  *
  * Returns an information for estimate how much given read-only
@@ -1557,7 +1664,7 @@ int mdbx_env_set_syncbytes(MDB_env *env, size_t bytes);
  * Returns Number of transactions committed after the given was started for
  * read, or -1 on failure.
  */
-int mdbx_txn_straggler(MDB_txn *txn, int *percent);
+LIBMDBX_API int mdbx_txn_straggler(MDB_txn *txn, int *percent);
 
 /* A callback function for killing a laggard readers,
  * but also could waiting ones. Called in case of MDB_MAP_FULL error.
@@ -1573,8 +1680,8 @@ int mdbx_txn_straggler(MDB_txn *txn, int *percent);
  * 	1 on success (reader was killed),
  * 	>1 on success (reader was SURE killed).
  */
-typedef int(MDBX_oom_func)(MDB_env *env, int pid, void *thread_id, size_t txn,
+typedef int(MDBX_oom_func)(MDB_env *env, int pid, mdbx_tid_t thread_id,
-                           unsigned gap, int retry);
+                           size_t txn, unsigned gap, int retry);
 
 /* Set the OOM callback.
  *
@@ -1584,7 +1691,7 @@ typedef int(MDBX_oom_func)(MDB_env *env, int pid, void *thread_id, size_t txn,
  * [in] env An environment handle returned by mdbx_env_create().
  * [in] oomfunc A #MDBX_oom_func function or NULL to disable.
  */
-void mdbx_env_set_oomfunc(MDB_env *env, MDBX_oom_func *oom_func);
+LIBMDBX_API void mdbx_env_set_oomfunc(MDB_env *env, MDBX_oom_func *oom_func);
 
 /* Get the current oom_func callback.
  *
@@ -1594,7 +1701,7 @@ void mdbx_env_set_oomfunc(MDB_env *env, MDBX_oom_func *oom_func);
  * [in] env An environment handle returned by mdbx_env_create().
  * Returns A #MDBX_oom_func function or NULL if disabled.
  */
-MDBX_oom_func *mdbx_env_get_oomfunc(MDB_env *env);
+LIBMDBX_API MDBX_oom_func *mdbx_env_get_oomfunc(MDB_env *env);
 
 #define MDBX_DBG_ASSERT 1
 #define MDBX_DBG_PRINT 2
@@ -1609,48 +1716,56 @@ MDBX_oom_func *mdbx_env_get_oomfunc(MDB_env *env);
 typedef void MDBX_debug_func(int type, const char *function, int line,
                              const char *msg, va_list args);
 
-int mdbx_setup_debug(int flags, MDBX_debug_func *logger, long edge_txn);
+LIBMDBX_API int mdbx_setup_debug(int flags, MDBX_debug_func *logger,
+                                 long edge_txn);
 
 typedef int MDBX_pgvisitor_func(size_t pgno, unsigned pgnumber, void *ctx,
                                 const char *dbi, const char *type, int nentries,
                                 int payload_bytes, int header_bytes,
                                 int unused_bytes);
-int mdbx_env_pgwalk(MDB_txn *txn, MDBX_pgvisitor_func *visitor, void *ctx);
+LIBMDBX_API int mdbx_env_pgwalk(MDB_txn *txn, MDBX_pgvisitor_func *visitor,
+                                void *ctx);
 
 typedef struct mdbx_canary { size_t x, y, z, v; } mdbx_canary;
 
-int mdbx_canary_put(MDB_txn *txn, const mdbx_canary *canary);
+LIBMDBX_API int mdbx_canary_put(MDB_txn *txn, const mdbx_canary *canary);
-size_t mdbx_canary_get(MDB_txn *txn, mdbx_canary *canary);
+LIBMDBX_API size_t mdbx_canary_get(MDB_txn *txn, mdbx_canary *canary);
 
 /* Returns:
  *	- MDBX_RESULT_TRUE	when no more data available
  *				or cursor not positioned;
  *	- MDBX_RESULT_FALSE	when data available;
  *	- Otherwise the error code. */
-int mdbx_cursor_eof(MDB_cursor *mc);
+LIBMDBX_API int mdbx_cursor_eof(MDB_cursor *mc);
 
 /* Returns: MDBX_RESULT_TRUE, MDBX_RESULT_FALSE or Error code. */
-int mdbx_cursor_on_first(MDB_cursor *mc);
+LIBMDBX_API int mdbx_cursor_on_first(MDB_cursor *mc);
 
 /* Returns: MDBX_RESULT_TRUE, MDBX_RESULT_FALSE or Error code. */
-int mdbx_cursor_on_last(MDB_cursor *mc);
+LIBMDBX_API int mdbx_cursor_on_last(MDB_cursor *mc);
 
-int mdbx_replace(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *new_data,
+LIBMDBX_API int mdbx_replace(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
-                 MDB_val *old_data, unsigned flags);
+                             MDB_val *new_data, MDB_val *old_data,
+                             unsigned flags);
 /* Same as mdbx_get(), but:
  * 1) if values_count is not NULL, then returns the count
  *    of multi-values/duplicates for a given key.
  * 2) updates the key for pointing to the actual key's data inside DB. */
-int mdbx_get_ex(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data,
+LIBMDBX_API int mdbx_get_ex(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
-                int *values_count);
+                            MDB_val *data, int *values_count);
 
-int mdbx_is_dirty(const MDB_txn *txn, const void *ptr);
+LIBMDBX_API int mdbx_is_dirty(const MDB_txn *txn, const void *ptr);
 
-int mdbx_dbi_open_ex(MDB_txn *txn, const char *name, unsigned flags,
+LIBMDBX_API int mdbx_dbi_open_ex(MDB_txn *txn, const char *name, unsigned flags,
-                     MDB_dbi *dbi, MDB_cmp_func *keycmp, MDB_cmp_func *datacmp);
+                                 MDB_dbi *dbi, MDB_cmp_func *keycmp,
+                                 MDB_cmp_func *datacmp);
 
 #ifdef __cplusplus
 }
 #endif
 
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
 #endif /* _MDBX_H_ */

src/barriers.h

@@ -1,156 +0,0 @@
-/*
- * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>.
- * Copyright 2015,2016 Peter-Service R&D LLC.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-/*****************************************************************************
- * Properly compiler/memory/coherence barriers
- * in the most portable way for libmdbx project.
- *
- * Feedback and comments are welcome.
- * https://gist.github.com/leo-yuriev/ba186a6bf5cf3a27bae7 */
-
-#pragma once
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#if defined(__mips) && defined(__linux)
-	/* Only MIPS has explicit cache control */
-#	include <asm/cachectl.h>
-#endif
-
-#if defined(__GNUC__) || defined(__clang__)
-#	define MDBX_INLINE __inline
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-#	include <intrin.h>
-#	if defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#		pragma intrinsic(__mf)
-#	elif defined(__i386__) || defined(__x86_64__)
-#		pragma intrinsic(_mm_mfence)
-#	endif
-#	define MDBX_INLINE __inline
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-#	include <mbarrier.h>
-#	define MDBX_INLINE inline
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) \
-	&& (defined(HP_IA64) || defined(__ia64))
-#	include <machine/sys/inline.h>
-#	define MDBX_INLINE
-#elif defined(__IBMC__) && defined(__powerpc)
-#	include <atomic.h>
-#	define MDBX_INLINE
-#elif defined(_AIX)
-#	include <builtins.h>
-#	include <sys/atomic_op.h>
-#	define MDBX_INLINE
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-#	include <machine/builtins.h>
-#	include <c_asm.h>
-#	define MDBX_INLINE
-#elif defined(__MWERKS__)
-	/* CodeWarrior - troubles ? */
-#	pragma gcc_extensions
-#	define MDBX_INLINE
-#elif defined(__SNC__)
-	/* Sony PS3 - troubles ? */
-#	define MDBX_INLINE
-#else
-#	define MDBX_INLINE
-#endif
-
-#if defined(__i386__) || defined(__x86_64__) \
-	|| defined(_M_AMD64) || defined(_M_IX86) \
-	|| defined(__i386) || defined(__amd64) \
-	|| defined(i386) || defined(__x86_64) \
-	|| defined(_AMD64_) || defined(_M_X64)
-#	define MDB_CACHE_IS_COHERENT 1
-#elif defined(__hppa) || defined(__hppa__)
-#	define MDB_CACHE_IS_COHERENT 1
-#endif
-
-#ifndef MDB_CACHE_IS_COHERENT
-#	define MDB_CACHE_IS_COHERENT 0
-#endif
-
-#define MDBX_BARRIER_COMPILER 0
-#define MDBX_BARRIER_MEMORY 1
-
-static MDBX_INLINE void mdbx_barrier(int type) {
-#if defined(__clang__)
-	__asm__ __volatile__ ("" ::: "memory");
-	if (type > MDBX_BARRIER_COMPILER)
-#	if __has_extension(c_atomic) || __has_extension(cxx_atomic)
-		__c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
-#	else
-		__sync_synchronize();
-#	endif
-#elif defined(__GNUC__)
-	__asm__ __volatile__ ("" ::: "memory");
-	if (type > MDBX_BARRIER_COMPILER)
-#	if defined(__ATOMIC_SEQ_CST)
-		__atomic_thread_fence(__ATOMIC_SEQ_CST);
-#	else
-		__sync_synchronize();
-#	endif
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-	__memory_barrier();
-	if (type > MDBX_BARRIER_COMPILER)
-#	if defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-		__mf();
-#	elif defined(__i386__) || defined(__x86_64__)
-		_mm_mfence();
-#	else
-#		error "Unknown target for Intel Compiler, please report to us."
-#	endif
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-	__compiler_barrier();
-	if (type > MDBX_BARRIER_COMPILER)
-		__machine_rw_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) \
-	&& (defined(HP_IA64) || defined(__ia64))
-	_Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
-	if (type > MDBX_BARRIER_COMPILER)
-		_Asm_mf();
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) \
-	|| defined(__ppc64__) || defined(__powerpc64__)
-	__fence();
-	if (type > MDBX_BARRIER_COMPILER)
-		__lwsync();
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-	__PAL_DRAINA(); /* LY: excessive ? */
-	__MB();
-#else
-#	error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-#define mdbx_compiler_barrier() \
-	mdbx_barrier(MDBX_BARRIER_COMPILER)
-#define mdbx_memory_barrier() \
-	mdbx_barrier(MDBX_BARRIER_MEMORY)
-#define mdbx_coherent_barrier() \
-	mdbx_barrier(MDB_CACHE_IS_COHERENT ? MDBX_BARRIER_COMPILER : MDBX_BARRIER_MEMORY)
-
-static MDBX_INLINE void mdbx_invalidate_cache(void *addr, int nbytes) {
-	mdbx_coherent_barrier();
-#if defined(__mips) && defined(__linux)
-	/* MIPS has cache coherency issues.
-	 * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-	cacheflush(addr, nbytes, DCACHE);
-#elif defined(_M_MRX000) || defined(_MIPS_)
-#	error "Sorry, cacheflush() for MIPS not implemented"
-#else
-	/* LY: assume no mmap/dcache issues. */
-	(void) addr;
-	(void) nbytes;
-#endif
-}

src/bits.h

@@ -0,0 +1,796 @@
+/*
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#pragma once
+/* *INDENT-OFF* */
+/* clang-format off */
+
+#ifndef _FILE_OFFSET_BITS
+#	define _FILE_OFFSET_BITS 64
+#endif
+
+#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
+#	define _CRT_SECURE_NO_WARNINGS
+#endif
+
+#ifdef _MSC_VER
+#pragma warning(disable : 4464) /* C4464: relative include path contains '..' */
+#pragma warning(disable : 4710) /* C4710: 'xyz': function not inlined */
+#pragma warning(disable : 4711) /* C4711: function 'xyz' selected for automatic inline expansion */
+//#pragma warning(disable : 4061) /* C4061: enumerator 'abc' in switch of enum 'xyz' is not explicitly handled by a case label */
+#pragma warning(disable : 4201) /* C4201: nonstandard extension used : nameless struct / union */
+#pragma warning(disable : 4706) /* C4706: assignment within conditional expression */
+#pragma warning(disable : 4127) /* C4127: conditional expression is constant */
+#endif                          /* _MSC_VER (warnings) */
+
+#include "../mdbx.h"
+#include "./defs.h"
+
+#if defined(USE_VALGRIND)
+#	include <valgrind/memcheck.h>
+#	ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
+/* LY: available since Valgrind 3.10 */
+#		define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
+#		define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
+#	endif
+#else
+#	define VALGRIND_CREATE_MEMPOOL(h,r,z)
+#	define VALGRIND_DESTROY_MEMPOOL(h)
+#	define VALGRIND_MEMPOOL_TRIM(h,a,s)
+#	define VALGRIND_MEMPOOL_ALLOC(h,a,s)
+#	define VALGRIND_MEMPOOL_FREE(h,a)
+#	define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
+#	define VALGRIND_MAKE_MEM_NOACCESS(a,s)
+#	define VALGRIND_MAKE_MEM_DEFINED(a,s)
+#	define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
+#	define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
+#	define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
+#	define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
+#	define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
+#endif /* USE_VALGRIND */
+
+#ifdef __SANITIZE_ADDRESS__
+#	include <sanitizer/asan_interface.h>
+#else
+#	define ASAN_POISON_MEMORY_REGION(addr, size) \
+		((void)(addr), (void)(size))
+#	define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
+		((void)(addr), (void)(size))
+#endif /* __SANITIZE_ADDRESS__ */
+
+#include "./osal.h"
+
+#ifndef MDB_DEBUG
+#	define MDB_DEBUG 0
+#endif
+
+#if MDB_DEBUG
+#	undef NDEBUG
+#endif
+
+#if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
+	/* Actualy libmdbx was not tested with compilers older than GCC from RHEL6.
+	 * 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.
+	 */
+#	warning "libmdbx required at least GCC 4.2 compatible C/C++ compiler."
+#endif
+
+#if defined(__GLIBC__) && !__GLIBC_PREREQ(2,12)
+	/* Actualy libmdbx was not tested with something older than glibc 2.12 (from RHEL6).
+	 * 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 systems.
+	 */
+#	warning "libmdbx required at least GLIBC 2.12."
+#endif
+
+#if defined(__i386) || defined(__x86_64) || defined(_M_IX86)
+#	define MISALIGNED_OK 1 /* TODO */
+#endif
+#ifndef MISALIGNED_OK
+#	define MISALIGNED_OK 0
+#endif /* MISALIGNED_OK */
+
+#if (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
+#	error "Sanity checking failed: Two's complement, reasonably sized integer types"
+#endif
+
+/*----------------------------------------------------------------------------*/
+
+#ifndef ARRAY_LENGTH
+#	ifdef __cplusplus
+		template <typename T, size_t N>
+		char (&__ArraySizeHelper(T (&array)[N]))[N];
+#		define ARRAY_LENGTH(array) (sizeof(::__ArraySizeHelper(array)))
+#	else
+#		define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
+#	endif
+#endif /* ARRAY_LENGTH */
+
+#ifndef ARRAY_END
+#	define ARRAY_END(array) (&array[ARRAY_LENGTH(array)])
+#endif /* ARRAY_END */
+
+#ifndef STRINGIFY
+#	define STRINGIFY_HELPER(x) #x
+#	define STRINGIFY(x) STRINGIFY_HELPER(x)
+#endif /* STRINGIFY */
+
+#ifndef offsetof
+#	define offsetof(type, member)  __builtin_offsetof(type, member)
+#endif /* offsetof */
+
+#ifndef container_of
+#	define container_of(ptr, type, member) \
+		((type *)((char *)(ptr) - offsetof(type, member)))
+#endif /* container_of */
+
+/* *INDENT-ON* */
+/* clang-format on */
+
+#define FIXME "FIXME: " __FILE__ ", " STRINGIFY(__LINE__)
+
+/*----------------------------------------------------------------------------*/
+
+/** handle for the DB used to track free pages. */
+#define FREE_DBI 0
+/** handle for the default DB. */
+#define MAIN_DBI 1
+/** Number of DBs in metapage (free and main) - also hardcoded elsewhere */
+#define CORE_DBS 2
+
+/** Number of meta pages - also hardcoded elsewhere */
+#define NUM_METAS 2
+
+/* A generic unsigned ID number. These were entryIDs in back-bdb.
+* Preferably it should have the same size as a pointer.
+*/
+typedef size_t MDB_ID;
+
+/** A page number in the database.
+*	Note that 64 bit page numbers are overkill, since pages themselves
+*	already represent 12-13 bits of addressable memory, and the OS will
+*	always limit applications to a maximum of 63 bits of address space.
+*
+*	@note In the #MDB_node structure, we only store 48 bits of this value,
+*	which thus limits us to only 60 bits of addressable data.
+*/
+typedef MDB_ID pgno_t;
+
+/** A transaction ID.
+*	See struct MDB_txn.mt_txnid for details.
+*/
+typedef MDB_ID txnid_t;
+
+/* An IDL is an ID List, a sorted array of IDs. The first
+* element of the array is a counter for how many actual
+* IDs are in the list. In the original back-bdb code, IDLs are
+* sorted in ascending order. For libmdb IDLs are sorted in
+* descending order.
+*/
+typedef MDB_ID *MDB_IDL;
+
+/* An ID2 is an ID/pointer pair.
+*/
+typedef struct MDB_ID2 {
+  MDB_ID mid; /* The ID */
+  void *mptr; /* The pointer */
+} MDB_ID2;
+
+/* An ID2L is an ID2 List, a sorted array of ID2s.
+* The first element's \b mid member is a count of how many actual
+* elements are in the array. The \b mptr member of the first element is
+* unused.
+* The array is sorted in ascending order by \b mid.
+*/
+typedef MDB_ID2 *MDB_ID2L;
+
+/**	Used for offsets within a single page.
+*	Since memory pages are typically 4 or 8KB in size, 12-13 bits,
+*	this is plenty.
+*/
+typedef uint16_t indx_t;
+
+#pragma pack(push, 1)
+
+/**	The information we store in a single slot of the reader table.
+*	In addition to a transaction ID, we also record the process and
+*	thread ID that owns a slot, so that we can detect stale information,
+*	e.g. threads or processes that went away without cleaning up.
+*	@note We currently don't check for stale records. We simply re-init
+*	the table when we know that we're the only process opening the
+*	lock file.
+*/
+typedef struct MDB_rxbody {
+  /**	Current Transaction ID when this transaction began, or (txnid_t)-1.
+  *	Multiple readers that start at the same time will probably have the
+  *	same ID here. Again, it's not important to exclude them from
+  *	anything; all we need to know is which version of the DB they
+  *	started from so we can avoid overwriting any data used in that
+  *	particular version.
+  */
+  volatile txnid_t mrb_txnid;
+  /** The process ID of the process owning this reader txn. */
+  volatile mdbx_pid_t mrb_pid;
+  /** The thread ID of the thread owning this txn. */
+  volatile mdbx_tid_t mrb_tid;
+} MDB_rxbody;
+
+/** The actual reader record, with cacheline padding. */
+typedef struct MDB_reader {
+  union {
+    MDB_rxbody mrx;
+/** shorthand for mrb_txnid */
+#define mr_txnid mru.mrx.mrb_txnid
+#define mr_pid mru.mrx.mrb_pid
+#define mr_tid mru.mrx.mrb_tid
+    /** cache line alignment */
+    char pad[(sizeof(MDB_rxbody) + MDBX_CACHELINE_SIZE - 1) &
+             ~(MDBX_CACHELINE_SIZE - 1)];
+  } mru;
+} MDB_reader;
+
+/** Information about a single database in the environment. */
+typedef struct MDB_db {
+  uint32_t md_xsize;        /**< also ksize for LEAF2 pages */
+  uint16_t md_flags;        /**< @ref mdbx_dbi_open */
+  uint16_t md_depth;        /**< depth of this tree */
+  pgno_t md_branch_pages;   /**< number of internal pages */
+  pgno_t md_leaf_pages;     /**< number of leaf pages */
+  pgno_t md_overflow_pages; /**< number of overflow pages */
+  size_t md_entries;        /**< number of data items */
+  pgno_t md_root;           /**< the root page of this tree */
+} MDB_db;
+
+/** Meta page content.
+*	A meta page is the start point for accessing a database snapshot.
+*	Pages 0-1 are meta pages. Transaction N writes meta page #(N % 2).
+*/
+typedef struct MDB_meta {
+  /** Stamp identifying this as an LMDB file. It must be set
+  *	to #MDB_MAGIC. */
+  uint32_t mm_magic;
+  /** Version number of this file. Must be set to #MDB_DATA_VERSION. */
+  uint32_t mm_version;
+  size_t mm_mapsize;       /**< size of mmap region */
+  MDB_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. @ref mdbx_env */
+#define mm_flags mm_dbs[FREE_DBI].md_flags
+  /** Last used page in the datafile.
+  *	Actually the file may be shorter if the freeDB lists the final pages.
+  */
+  pgno_t mm_last_pg;
+  volatile txnid_t mm_txnid; /**< txnid that committed this page */
+#define MDB_DATASIGN_NONE 0u
+#define MDB_DATASIGN_WEAK 1u
+  volatile uint64_t mm_datasync_sign;
+#define META_IS_WEAK(meta) ((meta)->mm_datasync_sign == MDB_DATASIGN_WEAK)
+#define META_IS_STEADY(meta) ((meta)->mm_datasync_sign > MDB_DATASIGN_WEAK)
+
+#if MDBX_MODE_ENABLED
+  volatile mdbx_canary mm_canary;
+#endif
+} MDB_meta;
+
+/** Common header for all page types. The page type depends on #mp_flags.
+*
+* #P_BRANCH and #P_LEAF pages have unsorted '#MDB_node's at the end, with
+* sorted #mp_ptrs[] entries referring to them. Exception: #P_LEAF2 pages
+* omit mp_ptrs and pack sorted #MDB_DUPFIXED values after the page header.
+*
+* #P_OVERFLOW records occupy one or more contiguous pages where only the
+* first has a page header. They hold the real data of #F_BIGDATA nodes.
+*
+* #P_SUBP sub-pages are small leaf "pages" with duplicate data.
+* A node with flag #F_DUPDATA but not #F_SUBDATA contains a sub-page.
+* (Duplicate data can also go in sub-databases, which use normal pages.)
+*
+* #P_META pages contain #MDB_meta, the start point of an LMDB snapshot.
+*
+* Each non-metapage up to #MDB_meta.%mm_last_pg is reachable exactly once
+* in the snapshot: Either used by a database or listed in a freeDB record.
+*/
+typedef struct MDB_page {
+#define mp_pgno mp_p.p_pgno
+#define mp_next mp_p.p_next
+  union {
+    pgno_t p_pgno;           /**< page number */
+    struct MDB_page *p_next; /**< for in-memory list of freed pages */
+  } mp_p;
+  uint16_t mp_leaf2_ksize; /**< key size if this is a LEAF2 page */
+                           /**	@defgroup mdbx_page	Page Flags
+                           *	@ingroup internal
+                           *	Flags for the page headers.
+                           *	@{
+                           */
+#define P_BRANCH 0x01      /**< branch page */
+#define P_LEAF 0x02        /**< leaf page */
+#define P_OVERFLOW 0x04    /**< overflow page */
+#define P_META 0x08        /**< meta page */
+#define P_DIRTY 0x10       /**< dirty page, also set for #P_SUBP pages */
+#define P_LEAF2 0x20       /**< for #MDB_DUPFIXED records */
+#define P_SUBP 0x40        /**< for #MDB_DUPSORT sub-pages */
+#define P_LOOSE 0x4000     /**< page was dirtied then freed, can be reused */
+#define P_KEEP 0x8000      /**< leave this page alone during spill */
+                           /** @} */
+  uint16_t mp_flags;       /**< @ref mdbx_page */
+#define mp_lower mp_pb.pb.pb_lower
+#define mp_upper mp_pb.pb.pb_upper
+#define mp_pages mp_pb.pb_pages
+  union {
+    struct {
+      indx_t pb_lower; /**< lower bound of free space */
+      indx_t pb_upper; /**< upper bound of free space */
+    } pb;
+    uint32_t pb_pages; /**< number of overflow pages */
+  } mp_pb;
+  indx_t mp_ptrs[1]; /**< dynamic size */
+} MDB_page;
+
+/** Size of the page header, excluding dynamic data at the end */
+#define PAGEHDRSZ ((unsigned)offsetof(MDB_page, mp_ptrs))
+
+/** Buffer for a stack-allocated meta page.
+*	The members define size and alignment, and silence type
+*	aliasing warnings.  They are not used directly; that could
+*	mean incorrectly using several union members in parallel.
+*/
+typedef union MDB_metabuf {
+  MDB_page mb_page;
+  struct {
+    char mm_pad[PAGEHDRSZ];
+    MDB_meta mm_meta;
+  } mb_metabuf;
+} MDB_metabuf;
+
+/* The header for the reader table (a memory-mapped lock file). */
+typedef struct MDBX_lockinfo {
+  /* Stamp identifying this as an LMDB file. It must be set to MDB_MAGIC. */
+  uint64_t mti_magic;
+  /* Format of this lock file. Must be set to MDB_LOCK_FORMAT. */
+  uint64_t mti_format;
+
+  /* The ID of the last transaction committed to the database.
+   * This is recorded here only for convenience; the value can always
+   * be determined by reading the main database meta pages. */
+  volatile txnid_t mti_txnid;
+#ifdef MDBX_OSAL_LOCK
+  MDBX_OSAL_LOCK mti_wmutex;
+#endif
+
+  /* The number of slots that have been used in the reader table.
+  * This always records the maximum count, it is not decremented
+  * when readers release their slots. */
+  __cache_aligned volatile unsigned mti_numreaders;
+#ifdef MDBX_OSAL_LOCK
+  /* Mutex protecting access to this table. */
+  MDBX_OSAL_LOCK mti_rmutex;
+#endif
+  MDB_reader mti_readers[1];
+} MDBX_lockinfo;
+
+#pragma pack(pop)
+
+/** Auxiliary DB info.
+*	The information here is mostly static/read-only. There is
+*	only a single copy of this record in the environment.
+*/
+typedef struct MDB_dbx {
+  MDB_val md_name;       /**< name of the database */
+  MDB_cmp_func *md_cmp;  /**< function for comparing keys */
+  MDB_cmp_func *md_dcmp; /**< function for comparing data items */
+} MDB_dbx;
+
+#if MDBX_MODE_ENABLED
+#define MDBX_MODE_SALT 0
+#else
+#error !?
+#endif
+
+/** A database transaction.
+*	Every operation requires a transaction handle.
+*/
+struct MDB_txn {
+#define MDBX_MT_SIGNATURE (0x93D53A31 ^ MDBX_MODE_SALT)
+  unsigned mt_signature;
+  MDB_txn *mt_parent; /**< parent of a nested txn */
+  /** Nested txn under this txn, set together with flag #MDB_TXN_HAS_CHILD */
+  MDB_txn *mt_child;
+  pgno_t mt_next_pgno; /**< next unallocated page */
+  /** The ID of this transaction. IDs are integers incrementing from 1.
+  *	Only committed write transactions increment the ID. If a transaction
+  *	aborts, the ID may be re-used by the next writer.
+  */
+  txnid_t mt_txnid;
+  MDB_env *mt_env; /**< the DB environment */
+                   /** The list of reclaimed txns from freeDB */
+  MDB_IDL mt_lifo_reclaimed;
+  /** The list of pages that became unused during this transaction.
+  */
+  MDB_IDL mt_free_pgs;
+  /** The list of loose pages that became unused and may be reused
+  *	in this transaction, linked through #NEXT_LOOSE_PAGE(page).
+  */
+  MDB_page *mt_loose_pgs;
+  /** Number of loose pages (#mt_loose_pgs) */
+  int mt_loose_count;
+  /** The sorted list of dirty pages we temporarily wrote to disk
+  *	because the dirty list was full. page numbers in here are
+  *	shifted left by 1, deleted slots have the LSB set.
+  */
+  MDB_IDL mt_spill_pgs;
+  union {
+    /** For write txns: Modified pages. Sorted when not MDB_WRITEMAP. */
+    MDB_ID2L dirty_list;
+    /** For read txns: This thread/txn's reader table slot, or NULL. */
+    MDB_reader *reader;
+  } mt_u;
+  /** Array of records for each DB known in the environment. */
+  MDB_dbx *mt_dbxs;
+  /** Array of MDB_db records for each known DB */
+  MDB_db *mt_dbs;
+  /** Array of sequence numbers for each DB handle */
+  unsigned *mt_dbiseqs;
+/** @defgroup mt_dbflag	Transaction DB Flags
+*	@ingroup internal
+* @{
+*/
+#define DB_DIRTY 0x01    /**< DB was written in this txn */
+#define DB_STALE 0x02    /**< Named-DB record is older than txnID */
+#define DB_NEW 0x04      /**< Named-DB handle opened in this txn */
+#define DB_VALID 0x08    /**< DB handle is valid, see also #MDB_VALID */
+#define DB_USRVALID 0x10 /**< As #DB_VALID, but not set for #FREE_DBI */
+#define DB_DUPDATA 0x20  /**< DB is #MDB_DUPSORT data */
+  /** @} */
+  /** In write txns, array of cursors for each DB */
+  MDB_cursor **mt_cursors;
+  /** Array of flags for each DB */
+  unsigned char *mt_dbflags;
+  /**	Number of DB records in use, or 0 when the txn is finished.
+  *	This number only ever increments until the txn finishes; we
+  *	don't decrement it when individual DB handles are closed.
+  */
+  MDB_dbi mt_numdbs;
+
+/** @defgroup mdbx_txn	Transaction Flags
+*	@ingroup internal
+*	@{
+*/
+/** #mdbx_txn_begin() flags */
+#define MDB_TXN_BEGIN_FLAGS (MDB_NOMETASYNC | MDB_NOSYNC | MDB_RDONLY)
+#define MDB_TXN_NOMETASYNC                                                     \
+  MDB_NOMETASYNC                  /**< don't sync meta for this txn on commit */
+#define MDB_TXN_NOSYNC MDB_NOSYNC /**< don't sync this txn on commit */
+#define MDB_TXN_RDONLY MDB_RDONLY /**< read-only transaction */
+                                  /* internal txn flags */
+#define MDB_TXN_WRITEMAP                                                       \
+  MDB_WRITEMAP                 /**< copy of #MDB_env flag in writers           \
+                                          */
+#define MDB_TXN_FINISHED 0x01  /**< txn is finished or never began */
+#define MDB_TXN_ERROR 0x02     /**< txn is unusable after an error */
+#define MDB_TXN_DIRTY 0x04     /**< must write, even if dirty list is empty */
+#define MDB_TXN_SPILLS 0x08    /**< txn or a parent has spilled pages */
+#define MDB_TXN_HAS_CHILD 0x10 /**< txn has an #MDB_txn.%mt_child */
+/** most operations on the txn are currently illegal */
+#define MDB_TXN_BLOCKED (MDB_TXN_FINISHED | MDB_TXN_ERROR | MDB_TXN_HAS_CHILD)
+  /** @} */
+  unsigned mt_flags; /**< @ref mdbx_txn */
+  /** #dirty_list room: Array size - \#dirty pages visible to this txn.
+  *	Includes ancestor txns' dirty pages not hidden by other txns'
+  *	dirty/spilled pages. Thus commit(nested txn) has room to merge
+  *	dirty_list into mt_parent after freeing hidden mt_parent pages.
+  */
+  unsigned mt_dirty_room;
+
+#if MDBX_MODE_ENABLED
+  mdbx_canary mt_canary;
+#endif
+};
+
+/** Enough space for 2^32 nodes with minimum of 2 keys per node. I.e., plenty.
+* At 4 keys per node, enough for 2^64 nodes, so there's probably no need to
+* raise this on a 64 bit machine.
+*/
+#define CURSOR_STACK 32
+
+struct MDB_xcursor;
+
+/** Cursors are used for all DB operations.
+*	A cursor holds a path of (page pointer, key index) from the DB
+*	root to a position in the DB, plus other state. #MDB_DUPSORT
+*	cursors include an xcursor to the current data item. Write txns
+*	track their cursors and keep them up to date when data moves.
+*	Exception: An xcursor's pointer to a #P_SUBP page can be stale.
+*	(A node with #F_DUPDATA but no #F_SUBDATA contains a subpage).
+*/
+struct MDB_cursor {
+#define MDBX_MC_SIGNATURE (0xFE05D5B1 ^ MDBX_MODE_SALT)
+#define MDBX_MC_READY4CLOSE (0x2817A047 ^ MDBX_MODE_SALT)
+#define MDBX_MC_WAIT4EOT (0x90E297A7 ^ MDBX_MODE_SALT)
+  unsigned mc_signature;
+  /** Next cursor on this DB in this txn */
+  MDB_cursor *mc_next;
+  /** Backup of the original cursor if this cursor is a shadow */
+  MDB_cursor *mc_backup;
+  /** Context used for databases with #MDB_DUPSORT, otherwise NULL */
+  struct MDB_xcursor *mc_xcursor;
+  /** The transaction that owns this cursor */
+  MDB_txn *mc_txn;
+  /** The database handle this cursor operates on */
+  MDB_dbi mc_dbi;
+  /** The database record for this cursor */
+  MDB_db *mc_db;
+  /** The database auxiliary record for this cursor */
+  MDB_dbx *mc_dbx;
+  /** The @ref mt_dbflag for this database */
+  uint8_t *mc_dbflag;
+  uint16_t mc_snum;        /**< number of pushed pages */
+  uint16_t mc_top;         /**< index of top page, normally mc_snum-1 */
+                           /** @defgroup mdbx_cursor	Cursor Flags
+                           *	@ingroup internal
+                           *	Cursor state flags.
+                           *	@{
+                           */
+#define C_INITIALIZED 0x01 /**< cursor has been initialized and is valid */
+#define C_EOF 0x02         /**< No more data */
+#define C_SUB 0x04         /**< Cursor is a sub-cursor */
+#define C_DEL 0x08         /**< last op was a cursor_del */
+#define C_UNTRACK 0x40     /**< Un-track cursor when closing */
+#define C_RECLAIMING 0x80  /**< FreeDB lookup is prohibited */
+                           /** @} */
+  unsigned mc_flags;       /**< @ref mdbx_cursor */
+  MDB_page *mc_pg[CURSOR_STACK]; /**< stack of pushed pages */
+  indx_t mc_ki[CURSOR_STACK];    /**< stack of page indices */
+};
+
+/** Context for sorted-dup records.
+*	We could have gone to a fully recursive design, with arbitrarily
+*	deep nesting of sub-databases. But for now we only handle these
+*	levels - main DB, optional sub-DB, sorted-duplicate DB.
+*/
+typedef struct MDB_xcursor {
+  /** A sub-cursor for traversing the Dup DB */
+  MDB_cursor mx_cursor;
+  /** The database record for this Dup DB */
+  MDB_db mx_db;
+  /**	The auxiliary DB record for this Dup DB */
+  MDB_dbx mx_dbx;
+  /** The @ref mt_dbflag for this Dup DB */
+  unsigned char mx_dbflag;
+} MDB_xcursor;
+
+/** Check if there is an inited xcursor, so #XCURSOR_REFRESH() is proper */
+#define XCURSOR_INITED(mc)                                                     \
+  ((mc)->mc_xcursor && ((mc)->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED))
+
+/** Update sub-page pointer, if any, in \b mc->mc_xcursor.  Needed
+*	when the node which contains the sub-page may have moved.  Called
+*	with \b mp = mc->mc_pg[mc->mc_top], \b ki = mc->mc_ki[mc->mc_top].
+*/
+#define XCURSOR_REFRESH(mc, mp, ki)                                            \
+  do {                                                                         \
+    MDB_page *xr_pg = (mp);                                                    \
+    MDB_node *xr_node = NODEPTR(xr_pg, ki);                                    \
+    if ((xr_node->mn_flags & (F_DUPDATA | F_SUBDATA)) == F_DUPDATA)            \
+      (mc)->mc_xcursor->mx_cursor.mc_pg[0] = NODEDATA(xr_node);                \
+  } while (0)
+
+/** State of FreeDB old pages, stored in the MDB_env */
+typedef struct MDB_pgstate {
+  pgno_t *mf_pghead; /**< Reclaimed freeDB pages, or NULL before use */
+  txnid_t mf_pglast; /**< ID of last used record, or 0 if !mf_pghead */
+} MDB_pgstate;
+
+#define MDBX_LOCKINFO_WHOLE_SIZE                                               \
+  ((sizeof(MDBX_lockinfo) + MDBX_CACHELINE_SIZE - 1) &                         \
+   ~((size_t)MDBX_CACHELINE_SIZE - 1))
+
+/** Lockfile format signature: version, features and field layout */
+#define MDB_LOCK_FORMAT                                                        \
+  (((uint64_t)(MDBX_OSAL_LOCK_SIGN) << 32) +                                   \
+   ((MDBX_LOCKINFO_WHOLE_SIZE + MDBX_CACHELINE_SIZE - 1) << 16) +              \
+   (MDB_LOCK_VERSION) /* Flags which describe functionality */)
+
+/** The database environment. */
+struct MDB_env {
+#define MDBX_ME_SIGNATURE (0x9A899641 ^ MDBX_MODE_SALT)
+  unsigned me_signature;
+  mdbx_filehandle_t me_fd;  /**< The main data file */
+  mdbx_filehandle_t me_lfd; /**< The lock file */
+/** Failed to update the meta page. Probably an I/O error. */
+#define MDB_FATAL_ERROR 0x80000000U
+/** Some fields are initialized. */
+#define MDB_ENV_ACTIVE 0x20000000U
+/** me_txkey is set */
+#define MDB_ENV_TXKEY 0x10000000U
+  uint32_t me_flags;      /**< @ref mdbx_env */
+  unsigned me_psize;      /**< DB page size, inited from me_os_psize */
+  unsigned me_os_psize;   /**< OS page size, from mdbx_syspagesize() */
+  unsigned me_maxreaders; /**< size of the reader table */
+  /** Max #MDBX_lockinfo.mti_numreaders of interest to #mdbx_env_close() */
+  unsigned me_close_readers;
+  MDB_dbi me_numdbs;      /**< number of DBs opened */
+  MDB_dbi me_maxdbs;      /**< size of the DB table */
+  mdbx_pid_t me_pid;      /**< process ID of this env */
+  char *me_path;          /**< path to the DB files */
+  char *me_map;           /**< the memory map of the data file */
+  MDBX_lockinfo *me_txns; /**< the memory map of the lock file, never NULL */
+  void *me_pbuf;          /**< scratch area for DUPSORT put() */
+  MDB_txn *me_txn;        /**< current write transaction */
+  MDB_txn *me_txn0;       /**< prealloc'd write transaction */
+  size_t me_mapsize;      /**< size of the data memory map */
+  pgno_t me_maxpg;        /**< me_mapsize / me_psize */
+  MDB_dbx *me_dbxs;       /**< array of static DB info */
+  uint16_t *me_dbflags;   /**< array of flags from MDB_db.md_flags */
+  unsigned *me_dbiseqs;   /**< array of dbi sequence numbers */
+  mdbx_thread_key_t me_txkey; /**< thread-key for readers */
+  txnid_t me_pgoldest;        /**< ID of oldest reader last time we looked */
+  MDB_pgstate me_pgstate;     /**< state of old pages from freeDB */
+#define me_pglast me_pgstate.mf_pglast
+#define me_pghead me_pgstate.mf_pghead
+  MDB_page *me_dpages; /**< list of malloc'd blocks for re-use */
+                       /** IDL of pages that became unused in a write txn */
+  MDB_IDL me_free_pgs;
+  /** ID2L of pages written during a write txn. Length MDB_IDL_UM_SIZE. */
+  MDB_ID2L me_dirty_list;
+  /** Max number of freelist items that can fit in a single overflow page */
+  unsigned me_maxfree_1pg;
+  /** Max size of a node on a page */
+  unsigned me_nodemax;
+  unsigned me_maxkey_limit; /**< max size of a key */
+  int me_live_reader;       /**< have liveness lock in reader table */
+  void *me_userctx;         /**< User-settable context */
+#if MDB_DEBUG
+  MDB_assert_func *me_assert_func; /**< Callback for assertion failures */
+#endif
+  uint64_t me_sync_pending; /**< Total dirty/commited bytes since the last
+                                                    mdbx_env_sync() */
+  uint64_t
+      me_sync_threshold; /**< Treshold of above to force synchronous flush */
+#if MDBX_MODE_ENABLED
+  MDBX_oom_func *me_oom_func; /**< Callback for kicking laggard readers */
+#endif
+#ifdef USE_VALGRIND
+  int me_valgrind_handle;
+#endif
+};
+
+/** Nested transaction */
+typedef struct MDB_ntxn {
+  MDB_txn mnt_txn;         /**< the transaction */
+  MDB_pgstate mnt_pgstate; /**< parent transaction's saved freestate */
+} MDB_ntxn;
+
+/*----------------------------------------------------------------------------*/
+
+extern int mdbx_runtime_flags;
+extern MDBX_debug_func *mdbx_debug_logger;
+extern txnid_t mdbx_debug_edge;
+
+void mdbx_debug_log(int type, const char *function, int line, const char *fmt,
+                    ...)
+#if defined(__GNUC__) || __has_attribute(format)
+    __attribute__((format(printf, 4, 5)))
+#endif
+    ;
+
+void mdbx_panic(const char *fmt, ...)
+#if defined(__GNUC__) || __has_attribute(format)
+    __attribute__((format(printf, 1, 2)))
+#endif
+    ;
+
+#if MDB_DEBUG
+
+#define mdbx_assert_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_ASSERT)
+
+#define mdbx_audit_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_AUDIT)
+
+#define mdbx_debug_enabled(type)                                               \
+  unlikely(mdbx_runtime_flags &(type & (MDBX_DBG_TRACE | MDBX_DBG_EXTRA)))
+
+#else
+#ifndef NDEBUG
+#define mdbx_debug_enabled(type) (1)
+#else
+#define mdbx_debug_enabled(type) (0)
+#endif
+#define mdbx_audit_enabled() (0)
+#define mdbx_assert_enabled() (0)
+#endif /* MDB_DEBUG */
+
+#define mdbx_print(fmt, ...)                                                   \
+  mdbx_debug_log(MDBX_DBG_PRINT, NULL, 0, fmt, ##__VA_ARGS__)
+
+#define mdbx_debug(fmt, ...)                                                   \
+  do {                                                                         \
+    if (mdbx_debug_enabled(MDBX_DBG_TRACE))                                    \
+      mdbx_debug_log(MDBX_DBG_TRACE, __FUNCTION__, __LINE__, fmt "\n",         \
+                     ##__VA_ARGS__);                                           \
+  } while (0)
+
+#define mdbx_debug_print(fmt, ...)                                             \
+  do {                                                                         \
+    if (mdbx_debug_enabled(MDBX_DBG_TRACE))                                    \
+      mdbx_debug_log(MDBX_DBG_TRACE, NULL, 0, fmt, ##__VA_ARGS__);             \
+  } while (0)
+
+#define mdbx_debug_extra(fmt, ...)                                             \
+  do {                                                                         \
+    if (mdbx_debug_enabled(MDBX_DBG_EXTRA))                                    \
+      mdbx_debug_log(MDBX_DBG_EXTRA, __FUNCTION__, __LINE__, fmt,              \
+                     ##__VA_ARGS__);                                           \
+  } while (0)
+
+#define mdbx_debug_extra_print(fmt, ...)                                       \
+  do {                                                                         \
+    if (mdbx_debug_enabled(MDBX_DBG_EXTRA))                                    \
+      mdbx_debug_log(MDBX_DBG_EXTRA, NULL, 0, fmt, ##__VA_ARGS__);             \
+  } while (0)
+
+#define mdbx_ensure_msg(env, expr, msg)                                        \
+  do {                                                                         \
+    if (unlikely(!(expr)))                                                     \
+      mdbx_assert_fail(env, msg, __FUNCTION__, __LINE__);                      \
+  } while (0)
+
+#define mdbx_ensure(env, expr) mdbx_ensure_msg(env, expr, #expr)
+
+/* assert(3) variant in environment context */
+#define mdbx_assert(env, expr)                                                 \
+  do {                                                                         \
+    if (mdbx_assert_enabled())                                                 \
+      mdbx_ensure(env, expr);                                                  \
+  } while (0)
+
+/* assert(3) variant in cursor context */
+#define mdbx_cassert(mc, expr) mdbx_assert((mc)->mc_txn->mt_env, expr)
+
+/* assert(3) variant in transaction context */
+#define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
+
+/*----------------------------------------------------------------------------*/
+
+int mdbx_reader_check0(MDB_env *env, int rlocked, int *dead);
+
+#define METAPAGE_1(env) (&((MDB_metabuf *)(env)->me_map)->mb_metabuf.mm_meta)
+
+#define METAPAGE_2(env)                                                        \
+  (&((MDB_metabuf *)((env)->me_map + env->me_psize))->mb_metabuf.mm_meta)
+
+static __inline MDB_meta *mdbx_meta_head_w(MDB_env *env) {
+  MDB_meta *a = METAPAGE_1(env);
+  MDB_meta *b = METAPAGE_2(env);
+  txnid_t head_txnid = env->me_txns->mti_txnid;
+
+  mdbx_assert(env, a->mm_txnid != b->mm_txnid || head_txnid == 0);
+  if (a->mm_txnid == head_txnid)
+    return a;
+  if (likely(b->mm_txnid == head_txnid))
+    return b;
+
+  mdbx_debug("me_txns->mti_txnid not match meta-pages");
+  mdbx_assert(env, head_txnid == a->mm_txnid || head_txnid == b->mm_txnid);
+  env->me_flags |= MDB_FATAL_ERROR;
+  return a;
+}
+
+void mdbx_rthc_dtor(void *rthc);
+void mdbx_rthc_lock(void);
+void mdbx_rthc_unlock(void);
+int mdbx_rthc_alloc(mdbx_thread_key_t *key, MDB_reader *begin, MDB_reader *end);
+void mdbx_rthc_remove(mdbx_thread_key_t key);
+void mdbx_rthc_cleanup(void);

src/defs.h

@@ -0,0 +1,302 @@
+/*
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#pragma once
+/* *INDENT-OFF* */
+/* clang-format off */
+
+#ifndef __GNUC_PREREQ
+#	if defined(__GNUC__) && defined(__GNUC_MINOR__)
+#		define __GNUC_PREREQ(maj, min) \
+			((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
+#	else
+#		define __GNUC_PREREQ(maj, min) (0)
+#	endif
+#endif /* __GNUC_PREREQ */
+
+#ifndef __CLANG_PREREQ
+#	ifdef __clang__
+#		define __CLANG_PREREQ(maj,min) \
+			((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
+#	else
+#		define __CLANG_PREREQ(maj,min) (0)
+#	endif
+#endif /* __CLANG_PREREQ */
+
+#ifndef __GLIBC_PREREQ
+#	if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
+#		define __GLIBC_PREREQ(maj, min) \
+			((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
+#	else
+#		define __GLIBC_PREREQ(maj, min) (0)
+#	endif
+#endif /* __GLIBC_PREREQ */
+
+#ifndef __has_attribute
+#	define __has_attribute(x) (0)
+#endif
+
+#ifndef __has_feature
+#	define __has_feature(x) (0)
+#endif
+
+#ifndef __has_extension
+#	define __has_extension(x) (0)
+#endif
+
+#ifndef __has_builtin
+#	define __has_builtin(x) (0)
+#endif
+
+#if __has_feature(thread_sanitizer)
+#	define __SANITIZE_THREAD__ 1
+#endif
+
+#if __has_feature(address_sanitizer)
+#	define __SANITIZE_ADDRESS__ 1
+#endif
+
+/*----------------------------------------------------------------------------*/
+
+#ifndef __extern_C
+#	ifdef __cplusplus
+#		define __extern_C extern "C"
+#	else
+#		define __extern_C
+#	endif
+#endif /* __extern_C */
+
+#ifndef __cplusplus
+#	ifndef bool
+#		define bool _Bool
+#	endif
+#	ifndef true
+#		define true (1)
+#	endif
+#	ifndef false
+#		define false (0)
+#	endif
+#endif
+
+#if !defined(nullptr) && !defined(__cplusplus) || (__cplusplus < 201103L && !defined(_MSC_VER))
+#	define nullptr NULL
+#endif
+
+/*----------------------------------------------------------------------------*/
+
+#if !defined(__thread) && (defined(_MSC_VER) || defined(__DMC__))
+#	define __thread __declspec(thread)
+#endif /* __thread */
+
+#ifndef __alwaysinline
+#	if defined(__GNUC__) || __has_attribute(always_inline)
+#		define __alwaysinline __inline __attribute__((always_inline))
+#	elif defined(_MSC_VER)
+#		define __alwaysinline __forceinline
+#	else
+#		define __alwaysinline
+#	endif
+#endif /* __alwaysinline */
+
+#ifndef __noinline
+#	if defined(__GNUC__) || __has_attribute(noinline)
+#		define __noinline __attribute__((noinline))
+#	elif defined(_MSC_VER)
+#		define __noinline __declspec(noinline)
+#	elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
+#		define __noinline inline
+#	elif !defined(__INTEL_COMPILER)
+#		define __noinline /* FIXME ? */
+#	endif
+#endif /* __noinline */
+
+#ifndef __must_check_result
+#	if defined(__GNUC__) || __has_attribute(warn_unused_result)
+#		define __must_check_result __attribute__((warn_unused_result))
+#	else
+#		define __must_check_result
+#	endif
+#endif /* __must_check_result */
+
+#ifndef __deprecated
+#	if defined(__GNUC__) || __has_attribute(deprecated)
+#		define __deprecated __attribute__((deprecated))
+#	elif defined(_MSC_VER)
+#		define __deprecated __declspec(deprecated)
+#	else
+#		define __deprecated
+#	endif
+#endif /* __deprecated */
+
+#ifndef __packed
+#	if defined(__GNUC__) || __has_attribute(packed)
+#		define __packed __attribute__((packed))
+#	else
+#		define __packed
+#	endif
+#endif /* __packed */
+
+#ifndef __aligned
+#	if defined(__GNUC__) || __has_attribute(aligned)
+#		define __aligned(N) __attribute__((aligned(N)))
+#	elif defined(_MSC_VER)
+#		define __aligned(N) __declspec(align(N))
+#	else
+#		define __aligned(N)
+#	endif
+#endif /* __aligned */
+
+#ifndef __noreturn
+#	if defined(__GNUC__) || __has_attribute(noreturn)
+#		define __noreturn __attribute__((noreturn))
+#	elif defined(_MSC_VER)
+#		define __noreturn __declspec(noreturn)
+#	else
+#		define __noreturn
+#	endif
+#endif /* __noreturn */
+
+#ifndef __nothrow
+#	if defined(__GNUC__) || __has_attribute(nothrow)
+#		define __nothrow __attribute__((nothrow))
+#	elif defined(_MSC_VER) && defined(__cplusplus)
+#		define __nothrow __declspec(nothrow)
+#	else
+#		define __nothrow
+#	endif
+#endif /* __nothrow */
+
+#ifndef __pure_function
+	/* Many functions have no effects except the return value and their
+	 * return value depends only on the parameters and/or global variables.
+	 * Such a function can be subject to common subexpression elimination
+	 * and loop optimization just as an arithmetic operator would be.
+	 * These functions should be declared with the attribute pure. */
+#	if defined(__GNUC__) || __has_attribute(pure)
+#		define __pure_function __attribute__((pure))
+#	else
+#		define __pure_function
+#	endif
+#endif /* __pure_function */
+
+#ifndef __const_function
+	/* Many functions do not examine any values except their arguments,
+	 * and have no effects except the return value. Basically this is just
+	 * slightly more strict class than the PURE attribute, since function
+	 * is not allowed to read global memory.
+	 *
+	 * Note that a function that has pointer arguments and examines the
+	 * data pointed to must not be declared const. Likewise, a function
+	 * that calls a non-const function usually must not be const.
+	 * It does not make sense for a const function to return void. */
+#	if defined(__GNUC__) || __has_attribute(const)
+#		define __const_function __attribute__((const))
+#	else
+#		define __const_function
+#	endif
+#endif /* __const_function */
+
+#ifndef __dll_hidden
+#	if defined(__GNUC__) || __has_attribute(visibility)
+#		define __hidden __attribute__((visibility("hidden")))
+#	else
+#		define __hidden
+#	endif
+#endif /* __dll_hidden */
+
+#ifndef __optimize
+#	if defined(__OPTIMIZE__)
+#		if defined(__clang__) && !__has_attribute(optimize)
+#			define __optimize(ops)
+#		elif defined(__GNUC__) || __has_attribute(optimize)
+#			define __optimize(ops) __attribute__((optimize(ops)))
+#		else
+#			define __optimize(ops)
+#		endif
+#	else
+#			define __optimize(ops)
+#	endif
+#endif /* __optimize */
+
+#ifndef __hot
+#	if defined(__OPTIMIZE__)
+#		if defined(__clang__) && !__has_attribute(hot)
+			/* just put frequently used functions in separate section */
+#			define __hot __attribute__((section("text.hot"))) __optimize("O3")
+#		elif defined(__GNUC__) || __has_attribute(hot)
+#			define __hot __attribute__((hot)) __optimize("O3")
+#		else
+#			define __hot  __optimize("O3")
+#		endif
+#	else
+#		define __hot
+#	endif
+#endif /* __hot */
+
+#ifndef __cold
+#	if defined(__OPTIMIZE__)
+#		if defined(__clang__) && !__has_attribute(cold)
+			/* just put infrequently used functions in separate section */
+#			define __cold __attribute__((section("text.unlikely"))) __optimize("Os")
+#		elif defined(__GNUC__) || __has_attribute(cold)
+#			define __cold __attribute__((cold)) __optimize("Os")
+#		else
+#			define __cold __optimize("Os")
+#		endif
+#	else
+#		define __cold
+#	endif
+#endif /* __cold */
+
+#ifndef __flatten
+#	if defined(__OPTIMIZE__) && (defined(__GNUC__) || __has_attribute(flatten))
+#		define __flatten __attribute__((flatten))
+#	else
+#		define __flatten
+#	endif
+#endif /* __flatten */
+
+#ifndef likely
+#	if defined(__GNUC__) || defined(__clang__)
+#		define likely(cond) __builtin_expect(!!(cond), 1)
+#	else
+#		define likely(x) (x)
+#	endif
+#endif /* likely */
+
+#ifndef unlikely
+#	if defined(__GNUC__) || defined(__clang__)
+#		define unlikely(cond) __builtin_expect(!!(cond), 0)
+#	else
+#		define unlikely(x) (x)
+#	endif
+#endif /* unlikely */
+
+/*----------------------------------------------------------------------------*/
+
+/* Wrapper around __func__, which is a C99 feature */
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
+#	define mdbx_func_ __func__
+#elif (defined(__GNUC__) && __GNUC__ >= 2) || defined(__clang__) || defined(_MSC_VER)
+#	define mdbx_func_ __FUNCTION__
+#else
+#	define mdbx_func_ "<mdbx_unknown>"
+#endif
+
+/* *INDENT-ON* */
+/* clang-format on */
+
+#define MDBX_TETRAD(a, b, c, d)                                                \
+  ((uint32_t)(a) << 24 | (uint32_t)(b) << 16 | (uint32_t)(c) << 8 |            \
+   (uint32_t)(d))

src/lck-posix.c

@@ -0,0 +1,251 @@
+/*
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#include "./bits.h"
+
+/* Some platforms define the EOWNERDEAD error code
+ * even though they don't support Robust Mutexes.
+ * Compile with -DMDB_USE_ROBUST=0. */
+#ifndef MDB_USE_ROBUST
+/* Howard Chu: Android currently lacks Robust Mutex support */
+#if defined(EOWNERDEAD) &&                                                     \
+    !defined(ANDROID) /* LY: glibc before 2.10 has a troubles with Robust      \
+                         Mutex too. */                                         \
+    && __GLIBC_PREREQ(2, 10)
+#define MDB_USE_ROBUST 1
+#else
+#define MDB_USE_ROBUST 0
+#endif
+#endif /* MDB_USE_ROBUST */
+
+/*----------------------------------------------------------------------------*/
+/* rthc */
+
+static mdbx_mutex_t mdbx_rthc_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+void mdbx_rthc_lock(void) {
+  mdbx_ensure(NULL, pthread_mutex_lock(&mdbx_rthc_mutex) == 0);
+}
+
+void mdbx_rthc_unlock(void) {
+  mdbx_ensure(NULL, pthread_mutex_unlock(&mdbx_rthc_mutex) == 0);
+}
+
+/*----------------------------------------------------------------------------*/
+/* lck */
+
+static int mdbx_lck_op(mdbx_filehandle_t fd, int op, int lck, off_t offset);
+static int mdbx_mutex_failed(MDB_env *env, pthread_mutex_t *mutex, int rc);
+
+int mdbx_lck_init(MDB_env *env) {
+  pthread_mutexattr_t ma;
+  int rc = pthread_mutexattr_init(&ma);
+  if (rc)
+    return rc;
+
+  rc = pthread_mutexattr_setpshared(&ma, PTHREAD_PROCESS_SHARED);
+  if (rc)
+    goto bailout;
+
+#if MDB_USE_ROBUST
+#if __GLIBC_PREREQ(2, 12)
+  rc = pthread_mutexattr_setrobust(&ma, PTHREAD_MUTEX_ROBUST);
+#else
+  rc = pthread_mutexattr_setrobust_np(&ma, PTHREAD_MUTEX_ROBUST_NP);
+#endif
+  if (rc)
+    goto bailout;
+#endif /* MDB_USE_ROBUST */
+
+#if _POSIX_C_SOURCE >= 199506L
+  rc = pthread_mutexattr_setprotocol(&ma, PTHREAD_PRIO_INHERIT);
+  if (rc == ENOTSUP)
+    rc = pthread_mutexattr_setprotocol(&ma, PTHREAD_PRIO_NONE);
+  if (rc)
+    goto bailout;
+#endif /* PTHREAD_PRIO_INHERIT */
+
+  rc = pthread_mutex_init(&env->me_txns->mti_rmutex, &ma);
+  if (rc)
+    goto bailout;
+  rc = pthread_mutex_init(&env->me_txns->mti_wmutex, &ma);
+
+bailout:
+  pthread_mutexattr_destroy(&ma);
+  return rc;
+}
+
+void mdbx_lck_destroy(MDB_env *env) {
+  if (env->me_lfd != INVALID_HANDLE_VALUE) {
+    /* try get exclusive access */
+    if (mdbx_lck_op(env->me_lfd, F_SETLK, F_WRLCK, 0) == 0) {
+      /* got exclusive, drown mutexes */
+      int rc = pthread_mutex_destroy(&env->me_txns->mti_rmutex);
+      if (rc == 0)
+        rc = pthread_mutex_destroy(&env->me_txns->mti_wmutex);
+      assert(rc == 0);
+      (void)rc;
+      /* lock would be released (by kernel) while the me_lfd will be closed */
+    }
+  }
+}
+
+static int mdbx_robust_lock(MDB_env *env, pthread_mutex_t *mutex) {
+  int rc = pthread_mutex_lock(mutex);
+  if (unlikely(rc != 0))
+    rc = mdbx_mutex_failed(env, mutex, rc);
+  return rc;
+}
+
+static int mdbx_robust_unlock(MDB_env *env, pthread_mutex_t *mutex) {
+  int rc = pthread_mutex_unlock(mutex);
+  if (unlikely(rc != 0))
+    rc = mdbx_mutex_failed(env, mutex, rc);
+  return rc;
+}
+
+int mdbx_rdt_lock(MDB_env *env) {
+  return mdbx_robust_lock(env, &env->me_txns->mti_rmutex);
+}
+
+void mdbx_rdt_unlock(MDB_env *env) {
+  int rc = mdbx_robust_unlock(env, &env->me_txns->mti_rmutex);
+  if (unlikely(rc != 0))
+    mdbx_panic("%s() failed: errcode %d\n", mdbx_func_, rc);
+}
+
+int mdbx_txn_lock(MDB_env *env) {
+  return mdbx_robust_lock(env, &env->me_txns->mti_wmutex);
+}
+
+void mdbx_txn_unlock(MDB_env *env) {
+  int rc = mdbx_robust_unlock(env, &env->me_txns->mti_wmutex);
+  if (unlikely(rc != 0))
+    mdbx_panic("%s() failed: errcode %d\n", mdbx_func_, rc);
+}
+
+int mdbx_lck_seize(MDB_env *env) {
+  /* try exclusive access */
+  int rc = mdbx_lck_op(env->me_lfd, F_SETLK, F_WRLCK, 0);
+  if (rc == 0)
+    /* got exclusive */
+    return MDBX_RESULT_TRUE;
+  if (rc == EAGAIN || rc == EACCES || rc == EBUSY) {
+    /* get shared access */
+    rc = mdbx_lck_op(env->me_lfd, F_SETLKW, F_RDLCK, 0);
+    if (rc == 0) {
+      /* got shared, try exclusive again */
+      rc = mdbx_lck_op(env->me_lfd, F_SETLK, F_WRLCK, 0);
+      if (rc == 0)
+        /* now got exclusive */
+        return MDBX_RESULT_TRUE;
+      if (rc == EAGAIN || rc == EACCES || rc == EBUSY)
+        /* unable exclusive, but stay shared */
+        return MDBX_RESULT_FALSE;
+    }
+  }
+  assert(rc != MDBX_RESULT_FALSE && rc != MDBX_RESULT_TRUE);
+  return rc;
+}
+
+int mdbx_lck_downgrade(MDB_env *env) {
+  return mdbx_lck_op(env->me_lfd, F_SETLK, F_RDLCK, 0);
+}
+
+int mdbx_rpid_set(MDB_env *env) {
+  return mdbx_lck_op(env->me_lfd, F_SETLK, F_WRLCK, env->me_pid);
+}
+
+int mdbx_rpid_clear(MDB_env *env) {
+  return mdbx_lck_op(env->me_lfd, F_SETLKW, F_UNLCK, env->me_pid);
+}
+
+int mdbx_rpid_check(MDB_env *env, mdbx_pid_t pid) {
+  int rc = mdbx_lck_op(env->me_lfd, F_GETLK, F_WRLCK, pid);
+  if (rc == 0)
+    return MDBX_RESULT_FALSE;
+  if (rc < 0 && -rc == pid)
+    return MDBX_RESULT_TRUE;
+  return rc;
+}
+
+static int mdbx_lck_op(mdbx_filehandle_t fd, int op, int lck, off_t offset) {
+  for (;;) {
+    int rc;
+    struct flock lock_op;
+    memset(&lock_op, 0, sizeof(lock_op));
+    lock_op.l_type = lck;
+    lock_op.l_whence = SEEK_SET;
+    lock_op.l_start = offset;
+    lock_op.l_len = 1;
+    if ((rc = fcntl(fd, op, &lock_op)) == 0) {
+      if (op == F_GETLK && lock_op.l_type != F_UNLCK)
+        rc = -lock_op.l_pid;
+    } else if ((rc = errno) == EINTR) {
+      continue;
+    }
+    return rc;
+  }
+}
+
+static int __cold mdbx_mutex_failed(MDB_env *env, mdbx_mutex_t *mutex, int rc) {
+#if MDB_USE_ROBUST
+  if (unlikely(rc == EOWNERDEAD)) {
+    int rlocked, rc2;
+
+    /* We own the mutex. Clean up after dead previous owner. */
+    rc = MDB_SUCCESS;
+    rlocked = (mutex == &env->me_txns->mti_rmutex);
+    if (!rlocked) {
+      /* Keep mtb.mti_txnid updated, otherwise next writer can
+       * overwrite data which latest meta page refers to.
+       *
+       * LY: Hm, how this can happen, if the mtb.mti_txnid
+       * is updating only at the finish of a successful commit ?
+       */
+      MDB_meta *meta = mdbx_meta_head_w(env);
+      assert(env->me_txns->mti_txnid == meta->mm_txnid);
+      (void)meta;
+      /* env is hosed if the dead thread was ours */
+      if (env->me_txn) {
+        env->me_flags |= MDB_FATAL_ERROR;
+        env->me_txn = NULL;
+        rc = MDB_PANIC;
+      }
+    }
+    mdbx_debug("%cmutex owner died, %s", (rlocked ? 'r' : 'w'),
+               (rc ? "this process' env is hosed" : "recovering"));
+    rc2 = mdbx_reader_check0(env, rlocked, NULL);
+    if (rc2 == 0)
+#if __GLIBC_PREREQ(2, 12)
+      rc2 = pthread_mutex_consistent(mutex);
+#else
+      rc2 = pthread_mutex_consistent_np(mutex);
+#endif
+    if (rc || (rc = rc2)) {
+      mdbx_debug("mutex recovery failed, %s", mdbx_strerror(rc));
+      pthread_mutex_unlock(mutex);
+    }
+  }
+#endif /* MDB_USE_ROBUST */
+
+  if (unlikely(rc)) {
+    mdbx_debug("lock mutex failed, %s", mdbx_strerror(rc));
+    if (rc != EDEADLK) {
+      env->me_flags |= MDB_FATAL_ERROR;
+      rc = MDB_PANIC;
+    }
+  }
+  return rc;
+}

src/lck-windows.c

@@ -0,0 +1,314 @@
+/*
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#include "./bits.h"
+
+/* PREAMBLE FOR WINDOWS:
+ *
+ * We are not concerned for performance here.
+ * If you are running Windows a performance could NOT be the goal.
+ * Otherwise please use Linux.
+ *
+ * Regards,
+ * LY
+ */
+
+/*----------------------------------------------------------------------------*/
+/* rthc */
+
+static CRITICAL_SECTION rthc_critical_section;
+
+static void NTAPI tls_callback(PVOID module, DWORD reason, PVOID reserved) {
+  (void)module;
+  (void)reserved;
+  switch (reason) {
+  case DLL_PROCESS_ATTACH:
+    InitializeCriticalSection(&rthc_critical_section);
+    break;
+  case DLL_PROCESS_DETACH:
+    DeleteCriticalSection(&rthc_critical_section);
+    break;
+
+  case DLL_THREAD_ATTACH:
+    break;
+  case DLL_THREAD_DETACH:
+    mdbx_rthc_cleanup();
+    break;
+  }
+}
+
+void mdbx_rthc_lock(void) { EnterCriticalSection(&rthc_critical_section); }
+
+void mdbx_rthc_unlock(void) { LeaveCriticalSection(&rthc_critical_section); }
+
+/* *INDENT-OFF* */
+/* clang-format off */
+#if defined(_MSC_VER)
+#  pragma const_seg(push)
+#  pragma data_seg(push)
+
+#  ifdef _WIN64
+     /* kick a linker to create the TLS directory if not already done */
+#    pragma comment(linker, "/INCLUDE:_tls_used")
+     /* Force some symbol references. */
+#    pragma comment(linker, "/INCLUDE:mdbx_tls_callback")
+     /* specific const-segment for WIN64 */
+#    pragma const_seg(".CRT$XLB")
+     const
+#  else
+     /* kick a linker to create the TLS directory if not already done */
+#    pragma comment(linker, "/INCLUDE:__tls_used")
+     /* Force some symbol references. */
+#    pragma comment(linker, "/INCLUDE:_mdbx_tls_callback")
+     /* specific data-segment for WIN32 */
+#    pragma data_seg(".CRT$XLB")
+#  endif
+
+   PIMAGE_TLS_CALLBACK mdbx_tls_callback = tls_callback;
+#  pragma data_seg(pop)
+#  pragma const_seg(pop)
+
+#elif defined(__GNUC__)
+#  ifdef _WIN64
+     const
+#  endif
+   PIMAGE_TLS_CALLBACK mdbx_tls_callback __attribute__((section(".CRT$XLB"), used))
+     = tls_callback;
+#else
+#  error FIXME
+#endif
+/* *INDENT-ON* */
+/* clang-format on */
+
+/*----------------------------------------------------------------------------*/
+
+#define LCK_SHARED 0
+#define LCK_EXCLUSIVE LOCKFILE_EXCLUSIVE_LOCK
+#define LCK_WAITFOR 0
+#define LCK_DONTWAIT LOCKFILE_FAIL_IMMEDIATELY
+
+static BOOL flock(mdbx_filehandle_t fd, DWORD flags, off_t offset,
+                  size_t bytes) {
+  OVERLAPPED ov;
+  ov.hEvent = 0;
+  ov.Offset = (DWORD)offset;
+  ov.OffsetHigh = HIGH_DWORD(offset);
+  return LockFileEx(fd, flags, 0, (DWORD)bytes, HIGH_DWORD(bytes), &ov);
+}
+
+static BOOL funlock(mdbx_filehandle_t fd, off_t offset, size_t bytes) {
+  return UnlockFile(fd, (DWORD)offset, HIGH_DWORD(offset), (DWORD)bytes,
+                    HIGH_DWORD(bytes));
+}
+
+/*----------------------------------------------------------------------------*/
+/* global `write` lock for write-txt processing,
+ * exclusive locking both meta-pages) */
+
+int mdbx_txn_lock(MDB_env *env) {
+  if (flock(env->me_fd, LCK_EXCLUSIVE | LCK_WAITFOR, 0, env->me_psize * 2))
+    return MDB_SUCCESS;
+  return GetLastError();
+}
+
+void mdbx_txn_unlock(MDB_env *env) {
+  if (!funlock(env->me_fd, 0, env->me_psize * 2))
+    mdbx_panic("%s failed: errcode %u", mdbx_func_, GetLastError());
+}
+
+/*----------------------------------------------------------------------------*/
+/* global `read` lock for readers registration,
+ * exclusive locking `mti_numreaders` (second) cacheline */
+
+#define LCK_LO_OFFSET 0
+#define LCK_LO_LEN offsetof(MDBX_lockinfo, mti_numreaders)
+#define LCK_UP_OFFSET LCK_LO_LEN
+#define LCK_UP_LEN (MDBX_LOCKINFO_WHOLE_SIZE - LCK_UP_OFFSET)
+#define LCK_LOWER LCK_LO_OFFSET, LCK_LO_LEN
+#define LCK_UPPER LCK_UP_OFFSET, LCK_UP_LEN
+
+int mdbx_rdt_lock(MDB_env *env) {
+  if (env->me_lfd == INVALID_HANDLE_VALUE)
+    return MDB_SUCCESS; /* readonly database in readonly filesystem */
+
+  /* transite from S-? (used) to S-E (locked), e.g. exlcusive lock upper-part */
+  if (flock(env->me_lfd, LCK_EXCLUSIVE | LCK_WAITFOR, LCK_UPPER))
+    return MDB_SUCCESS;
+  return GetLastError();
+}
+
+void mdbx_rdt_unlock(MDB_env *env) {
+  if (env->me_lfd != INVALID_HANDLE_VALUE) {
+    /* transite from S-E (locked) to S-? (used), e.g. unlock upper-part */
+    if (!funlock(env->me_lfd, LCK_UPPER))
+      mdbx_panic("%s failed: errcode %u", mdbx_func_, GetLastError());
+  }
+}
+
+/*----------------------------------------------------------------------------*/
+/* global `initial` lock for lockfile initialization,
+*  exclusive/shared locking first cacheline */
+
+/* FIXME: locking scheme/algo descritpion.
+ ?-?  = free
+ S-?  = used
+ E-?
+ ?-S
+ ?-E  = middle
+ S-S
+ S-E  = locked
+ E-S
+ E-E  = exclusive
+*/
+
+int mdbx_lck_init(MDB_env *env) {
+  (void)env;
+  return MDB_SUCCESS;
+}
+
+/* Seize state as exclusive (E-E and returns MDBX_RESULT_TRUE)
+ * or used (S-? and returns MDBX_RESULT_FALSE), otherwise returns an error */
+int mdbx_lck_seize(MDB_env *env) {
+  /* 1) now on ?-? (free), get ?-E (middle) */
+  if (!flock(env->me_lfd, LCK_EXCLUSIVE | LCK_WAITFOR, LCK_UPPER))
+    return GetLastError() /* 2) something went wrong, give up */;
+
+  /* 3) now on ?-E (middle), try E-E (exclusive) */
+  if (flock(env->me_lfd, LCK_EXCLUSIVE | LCK_DONTWAIT, LCK_LOWER))
+    return MDBX_RESULT_TRUE; /* 4) got E-E (exclusive), done */
+
+  /* 5) still on ?-E (middle) */
+  int rc = GetLastError();
+  if (rc != ERROR_SHARING_VIOLATION && rc != ERROR_LOCK_VIOLATION) {
+    /* 6) something went wrong, give up */
+    if (!funlock(env->me_lfd, LCK_UPPER)) {
+      rc = GetLastError();
+      mdbx_panic("%s(%s) failed: errcode %u", mdbx_func_,
+                 "?-E(middle) >> ?-?(free)", rc);
+    }
+    return rc;
+  }
+
+  /* 7) still on ?-E (middle), try S-E (locked) */
+  rc = flock(env->me_lfd, LCK_EXCLUSIVE | LCK_DONTWAIT, LCK_LOWER)
+           ? MDBX_RESULT_FALSE
+           : GetLastError();
+
+  /* 8) now on S-E (locked) or still on ?-E (middle),
+   *    transite to S-? (used) or ?-? (free) */
+  if (!funlock(env->me_lfd, LCK_UPPER)) {
+    rc = GetLastError();
+    mdbx_panic("%s(%s) failed: errcode %u", mdbx_func_,
+               "X-E(locked/middle) >> X-?(used/free)", rc);
+  }
+
+  /* 9) now on S-? (used, DONE) or ?-? (free, FAILURE) */
+  return rc;
+}
+
+/* Transite from exclusive state (E-E) to used (S-?) */
+int mdbx_lck_downgrade(MDB_env *env) {
+  int rc;
+
+  /* 1) now at E-E (exclusive), continue transition to ?_E (middle) */
+  if (!funlock(env->me_lfd, LCK_LOWER)) {
+    rc = GetLastError();
+    mdbx_panic("%s(%s) failed: errcode %u", mdbx_func_,
+               "E-E(exclusive) >> ?-E(middle)", rc);
+  }
+
+  /* 2) now at ?-E (middle), transite to S-E (locked) */
+  if (!flock(env->me_lfd, LCK_SHARED | LCK_DONTWAIT, LCK_LOWER)) {
+    rc = GetLastError() /* 3) something went wrong, give up */;
+    return rc;
+  }
+
+  /* 4) got S-E (locked), continue transition to S-? (used) */
+  if (!funlock(env->me_lfd, LCK_UPPER)) {
+    rc = GetLastError();
+    mdbx_panic("%s(%s) failed: errcode %u", mdbx_func_,
+               "S-E(locked) >> S-?(used)", rc);
+  }
+  return MDB_SUCCESS /* 5) now at S-? (used), done */;
+}
+
+void mdbx_lck_destroy(MDB_env *env) {
+  int rc;
+
+  if (env->me_fd != INVALID_HANDLE_VALUE) {
+    /* explicitly unlock to avoid latency for other processes (windows kernel
+     * releases such locks via deferred queues) */
+    while (funlock(env->me_fd, 0, env->me_psize * 2))
+      ;
+    rc = GetLastError();
+    assert(rc == ERROR_NOT_LOCKED);
+    (void)rc;
+    SetLastError(ERROR_SUCCESS);
+  }
+
+  if (env->me_lfd != INVALID_HANDLE_VALUE) {
+    /* double `unlock` for robustly remove overlapped shared/exclusive locks */
+    while (funlock(env->me_lfd, LCK_LOWER))
+      ;
+    assert(rc == ERROR_NOT_LOCKED);
+    (void)rc;
+    SetLastError(ERROR_SUCCESS);
+
+    while (funlock(env->me_lfd, LCK_UPPER))
+      ;
+    assert(rc == ERROR_NOT_LOCKED);
+    (void)rc;
+    SetLastError(ERROR_SUCCESS);
+  }
+}
+
+/*----------------------------------------------------------------------------*/
+/* reader checking (by pid) */
+
+int mdbx_rpid_set(MDB_env *env) {
+  (void)env;
+  return MDB_SUCCESS;
+}
+
+int mdbx_rpid_clear(MDB_env *env) {
+  (void)env;
+  return MDB_SUCCESS;
+}
+
+int mdbx_rpid_check(MDB_env *env, mdbx_pid_t pid) {
+  (void)env;
+  HANDLE hProcess = OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION, FALSE, pid);
+  int rc;
+  if (hProcess) {
+    rc = WaitForSingleObject(hProcess, 0);
+    CloseHandle(hProcess);
+  } else {
+    rc = GetLastError();
+  }
+
+  switch (rc) {
+  case ERROR_INVALID_PARAMETER:
+    /* pid seem invalid */
+    return MDBX_RESULT_FALSE;
+  case WAIT_OBJECT_0:
+    /* process just exited */
+    return MDBX_RESULT_FALSE;
+  case WAIT_TIMEOUT:
+    /* pid running */
+    return MDBX_RESULT_TRUE;
+  default:
+    /* failure */
+    return rc;
+  }
+}

src/midl.h

@@ -1,19 +1,19 @@
-/** A generic unsigned ID number. These were entryIDs in back-bdb.
+/*
- *	Preferably it should have the same size as a pointer.
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
  */
-typedef size_t MDB_ID;
-
-/** An IDL is an ID List, a sorted array of IDs. The first
- * element of the array is a counter for how many actual
- * IDs are in the list. In the original back-bdb code, IDLs are
- * sorted in ascending order. For libmdb IDLs are sorted in
- * descending order.
- */
-typedef MDB_ID *MDB_IDL;
 
 /* IDL sizes - likely should be even bigger
- *   limiting factors: sizeof(ID), thread stack size
+ * limiting factors: sizeof(ID), thread stack size */
- */
 #define MDB_IDL_LOGN 16 /* DB_SIZE is 2^16, UM_SIZE is 2^17 */
 #define MDB_IDL_DB_SIZE (1 << MDB_IDL_LOGN)
 #define MDB_IDL_UM_SIZE (1 << (MDB_IDL_LOGN + 1))
@@ -27,27 +27,12 @@ typedef MDB_ID *MDB_IDL;
 #define MDB_IDL_FIRST(ids) ((ids)[1])
 #define MDB_IDL_LAST(ids) ((ids)[(ids)[0]])
 
-/** Current max length of an #mdbx_midl_alloc()ed IDL */
+/* Current max length of an #mdbx_midl_alloc()ed IDL */
 #define MDB_IDL_ALLOCLEN(ids) ((ids)[-1])
 
-/** Append ID to IDL. The IDL must be big enough. */
+/* Append ID to IDL. The IDL must be big enough. */
 #define mdbx_midl_xappend(idl, id)                                             \
   do {                                                                         \
     MDB_ID *xidl = (idl), xlen = ++(xidl[0]);                                  \
     xidl[xlen] = (id);                                                         \
   } while (0)
-
-/** An ID2 is an ID/pointer pair.
- */
-typedef struct MDB_ID2 {
-  MDB_ID mid; /**< The ID */
-  void *mptr; /**< The pointer */
-} MDB_ID2;
-
-/** An ID2L is an ID2 List, a sorted array of ID2s.
- * The first element's \b mid member is a count of how many actual
- * elements are in the array. The \b mptr member of the first element is
- * unused.
- * The array is sorted in ascending order by \b mid.
- */
-typedef MDB_ID2 *MDB_ID2L;

src/osal.c

@@ -0,0 +1,625 @@
+/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
+
+/*
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#include "./bits.h"
+
+#if defined(_WIN32) || defined(_WIN64)
+static int waitfor2errcode(DWORD result) {
+  switch (result) {
+  case WAIT_OBJECT_0:
+    return MDB_SUCCESS;
+  case WAIT_FAILED:
+    return GetLastError();
+  case WAIT_ABANDONED:
+    return ERROR_ABANDONED_WAIT_0;
+  case WAIT_IO_COMPLETION:
+    return ERROR_USER_APC;
+  case WAIT_TIMEOUT:
+    return ERROR_TIMEOUT;
+  default:
+    return ERROR_UNHANDLED_ERROR;
+  }
+}
+#endif /* _WIN32 || _WIN64 */
+
+/*----------------------------------------------------------------------------*/
+
+#ifndef _MSC_VER
+/* Prototype should match libc runtime. ISO POSIX (2003) & LSB 3.1 */
+__nothrow __noreturn void __assert_fail(const char *assertion, const char *file,
+                                        unsigned line, const char *function);
+#else
+__extern_C __declspec(dllimport) void __cdecl _assert(char const *message,
+                                                      char const *filename,
+                                                      unsigned line);
+#endif /* _MSC_VER */
+
+#ifndef mdbx_assert_fail
+void __cold mdbx_assert_fail(MDB_env *env, const char *msg, const char *func,
+                             int line) {
+#if MDB_DEBUG
+  if (env && env->me_assert_func) {
+    env->me_assert_func(env, msg, func, line);
+    return;
+  }
+#else
+  (void)env;
+#endif /* MDB_DEBUG */
+
+  if (mdbx_debug_logger)
+    mdbx_debug_log(MDBX_DBG_ASSERT, func, line, "assert: %s\n", msg);
+#ifndef _MSC_VER
+  __assert_fail(msg, "mdbx", line, func);
+#else
+  _assert(msg, func, line);
+#endif /* _MSC_VER */
+}
+#endif /* mdbx_assert_fail */
+
+__cold void mdbx_panic(const char *fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+#ifdef _MSC_VER
+  if (IsDebuggerPresent()) {
+    OutputDebugString("\r\n" FIXME "\r\n");
+    FatalExit(ERROR_UNHANDLED_ERROR);
+  }
+#elif _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L ||                    \
+    (__GLIBC_PREREQ(1, 0) && !__GLIBC_PREREQ(2, 10) && defined(_GNU_SOURCE))
+  vdprintf(STDERR_FILENO, fmt, ap);
+#else
+#error FIXME
+#endif
+  va_end(ap);
+  abort();
+}
+
+/*----------------------------------------------------------------------------*/
+
+#ifndef mdbx_asprintf
+int mdbx_asprintf(char **strp, const char *fmt, ...) {
+  va_list ap, ones;
+
+  va_start(ap, fmt);
+  va_copy(ones, ap);
+#ifdef _MSC_VER
+  int needed = _vscprintf(fmt, ap);
+#elif defined(_BSD_SOURCE) || _XOPEN_SOURCE >= 500 ||                          \
+    defined(_ISOC99_SOURCE) || _POSIX_C_SOURCE >= 200112L
+  int needed = vsnprintf(nullptr, 0, fmt, ap);
+#else
+#error FIXME
+#endif
+  va_end(ap);
+
+  if (unlikely(needed < 0 || needed >= INT_MAX)) {
+    *strp = NULL;
+    va_end(ones);
+    return needed;
+  }
+
+  *strp = malloc(needed + 1);
+  if (unlikely(*strp == NULL)) {
+    va_end(ones);
+    return -ENOMEM;
+  }
+
+#ifdef _MSC_VER
+  int actual = vsnprintf_s(*strp, needed + 1, _TRUNCATE, fmt, ones);
+#elif defined(_BSD_SOURCE) || _XOPEN_SOURCE >= 500 ||                          \
+    defined(_ISOC99_SOURCE) || _POSIX_C_SOURCE >= 200112L
+  int actual = vsnprintf(*strp, needed + 1, fmt, ones);
+#else
+#error FIXME
+#endif
+  va_end(ones);
+
+  assert(actual == needed);
+  if (unlikely(actual < 0)) {
+    free(*strp);
+    *strp = NULL;
+  }
+  return actual;
+}
+#endif /* mdbx_asprintf */
+
+#ifndef mdbx_memalign_alloc
+int mdbx_memalign_alloc(size_t alignment, size_t bytes, void **result) {
+#if _MSC_VER
+  *result = _aligned_malloc(bytes, alignment);
+  return *result ? MDB_SUCCESS : ERROR_OUTOFMEMORY;
+#elif __GLIBC_PREREQ(2, 16) || __STDC_VERSION__ >= 201112L
+  *result = memalign(alignment, bytes);
+  return *result ? MDB_SUCCESS : errno;
+#elif _POSIX_VERSION >= 200112L
+  *result = NULL;
+  return posix_memalign(result, alignment, bytes);
+#else
+#error FIXME
+#endif
+}
+#endif /* mdbx_memalign_alloc */
+
+#ifndef mdbx_memalign_free
+void mdbx_memalign_free(void *ptr) {
+#if _MSC_VER
+  _aligned_free(ptr);
+#else
+  free(ptr);
+#endif
+}
+#endif /* mdbx_memalign_free */
+
+/*----------------------------------------------------------------------------*/
+
+int mdbx_mutex_init(mdbx_mutex_t *mutex) {
+#if defined(_WIN32) || defined(_WIN64)
+  *mutex = CreateMutex(NULL, FALSE, NULL);
+  return *mutex ? MDB_SUCCESS : GetLastError();
+#else
+  return pthread_mutex_init(mutex, NULL);
+#endif
+}
+
+int mdbx_mutex_destroy(mdbx_mutex_t *mutex) {
+#if defined(_WIN32) || defined(_WIN64)
+  return CloseHandle(*mutex) ? MDB_SUCCESS : GetLastError();
+#else
+  return pthread_mutex_destroy(mutex);
+#endif
+}
+
+int mdbx_mutex_lock(mdbx_mutex_t *mutex) {
+#if defined(_WIN32) || defined(_WIN64)
+  DWORD code = WaitForSingleObject(*mutex, INFINITE);
+  return waitfor2errcode(code);
+#else
+  return pthread_mutex_lock(mutex);
+#endif
+}
+
+int mdbx_mutex_unlock(mdbx_mutex_t *mutex) {
+#if defined(_WIN32) || defined(_WIN64)
+  return ReleaseMutex(*mutex) ? MDB_SUCCESS : GetLastError();
+#else
+  return pthread_mutex_unlock(mutex);
+#endif
+}
+
+/*----------------------------------------------------------------------------*/
+
+int mdbx_cond_init(mdbx_cond_t *cond) {
+#if defined(_WIN32) || defined(_WIN64)
+  *cond = CreateEvent(NULL, FALSE, FALSE, NULL);
+  return *cond ? MDB_SUCCESS : GetLastError();
+#else
+  return pthread_cond_init(cond, NULL);
+#endif
+}
+
+#ifndef mdbx_cond_destroy
+int mdbx_cond_destroy(mdbx_cond_t *cond) {
+#if defined(_WIN32) || defined(_WIN64)
+  return CloseHandle(*cond) ? MDB_SUCCESS : GetLastError();
+#else
+  return pthread_cond_destroy(cond);
+#endif
+}
+#endif /* mdbx_cond_destroy */
+
+int mdbx_cond_signal(mdbx_cond_t *cond) {
+#if defined(_WIN32) || defined(_WIN64)
+  return SetEvent(*cond) ? MDB_SUCCESS : GetLastError();
+#else
+  return pthread_cond_signal(cond);
+#endif
+}
+
+int mdbx_cond_wait(mdbx_cond_t *cond, mdbx_mutex_t *mutex) {
+#if defined(_WIN32) || defined(_WIN64)
+  DWORD code = SignalObjectAndWait(*mutex, *cond, INFINITE, FALSE);
+  if (code == WAIT_OBJECT_0)
+    code = WaitForSingleObject(*mutex, INFINITE);
+  return waitfor2errcode(code);
+#else
+  return pthread_cond_wait(cond, mutex);
+#endif
+}
+
+/*----------------------------------------------------------------------------*/
+
+int mdbx_openfile(const char *pathname, int flags, mode_t mode,
+                  mdbx_filehandle_t *fd) {
+  *fd = INVALID_HANDLE_VALUE;
+#if defined(_WIN32) || defined(_WIN64)
+  (void)mode;
+
+  DWORD DesiredAccess;
+  DWORD ShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
+  DWORD FlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
+  switch (flags & (O_RDONLY | O_WRONLY | O_RDWR)) {
+  default:
+    return ERROR_INVALID_PARAMETER;
+  case O_RDONLY:
+    DesiredAccess = GENERIC_READ;
+    break;
+  case O_WRONLY: /* assume for mdb_env_copy() and friends output */
+    DesiredAccess = GENERIC_WRITE;
+    ShareMode = 0;
+    FlagsAndAttributes |= FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH;
+    break;
+  case O_RDWR:
+    DesiredAccess = GENERIC_READ | GENERIC_WRITE;
+    break;
+  }
+
+  DWORD CreationDisposition;
+  switch (flags & (O_EXCL | O_CREAT)) {
+  default:
+    return ERROR_INVALID_PARAMETER;
+  case 0:
+    CreationDisposition = OPEN_EXISTING;
+    break;
+  case O_EXCL | O_CREAT:
+    CreationDisposition = CREATE_NEW;
+    FlagsAndAttributes |= FILE_ATTRIBUTE_NOT_CONTENT_INDEXED;
+    break;
+  case O_CREAT:
+    CreationDisposition = OPEN_ALWAYS;
+    FlagsAndAttributes |= FILE_ATTRIBUTE_NOT_CONTENT_INDEXED;
+    break;
+  }
+
+  *fd = CreateFileA(pathname, DesiredAccess, ShareMode, NULL,
+                    CreationDisposition, FlagsAndAttributes, NULL);
+
+  if (*fd == INVALID_HANDLE_VALUE)
+    return GetLastError();
+  if ((flags & O_CREAT) && GetLastError() != ERROR_ALREADY_EXISTS) {
+    /* set FILE_ATTRIBUTE_NOT_CONTENT_INDEXED for new file */
+    DWORD FileAttributes = GetFileAttributesA(pathname);
+    if (FileAttributes == INVALID_FILE_ATTRIBUTES ||
+        !SetFileAttributesA(pathname, FileAttributes |
+                                          FILE_ATTRIBUTE_NOT_CONTENT_INDEXED)) {
+      int rc = GetLastError();
+      CloseHandle(*fd);
+      *fd = INVALID_HANDLE_VALUE;
+      return rc;
+    }
+  }
+#else
+
+#ifdef O_CLOEXEC
+  flags |= O_CLOEXEC;
+#endif
+  *fd = open(pathname, flags, mode);
+  if (*fd < 0)
+    return errno;
+#if defined(FD_CLOEXEC) && defined(F_GETFD)
+  flags = fcntl(*fd, F_GETFD);
+  if (flags >= 0)
+    (void)fcntl(*fd, F_SETFD, flags | FD_CLOEXEC);
+#endif
+#endif
+  return MDB_SUCCESS;
+}
+
+int mdbx_closefile(mdbx_filehandle_t fd) {
+#if defined(_WIN32) || defined(_WIN64)
+  return CloseHandle(fd) ? MDB_SUCCESS : GetLastError();
+#else
+  return (close(fd) == 0) ? MDB_SUCCESS : errno;
+#endif
+}
+
+int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t bytes, off_t offset) {
+#if defined(_WIN32) || defined(_WIN64)
+  if (bytes > MAX_WRITE)
+    return ERROR_INVALID_PARAMETER;
+
+  OVERLAPPED ov;
+  ov.hEvent = 0;
+  ov.Offset = (DWORD)offset;
+  ov.OffsetHigh = HIGH_DWORD(offset);
+
+  DWORD read;
+  if (unlikely(!ReadFile(fd, buf, (DWORD)bytes, &read, &ov))) {
+    int rc = GetLastError();
+    if (rc == ERROR_HANDLE_EOF && read == 0 && offset == 0)
+      return ENOENT;
+    return rc;
+  }
+  return (read == bytes) ? MDB_SUCCESS : ERROR_READ_FAULT;
+#else
+  ssize_t read = pread(fd, buf, bytes, offset);
+  if (likely(bytes == (size_t)read))
+    return MDB_SUCCESS;
+  if (read < 0)
+    return errno;
+  return (read == 0 && offset == 0) ? ENOENT : EIO;
+#endif
+}
+
+int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf, size_t bytes,
+                off_t offset) {
+#if defined(_WIN32) || defined(_WIN64)
+  if (bytes > MAX_WRITE)
+    return ERROR_INVALID_PARAMETER;
+
+  OVERLAPPED ov;
+  ov.hEvent = 0;
+  ov.Offset = (DWORD)offset;
+  ov.OffsetHigh = HIGH_DWORD(offset);
+
+  DWORD written;
+  if (likely(WriteFile(fd, buf, (DWORD)bytes, &written, &ov)))
+    return (bytes == written) ? MDB_SUCCESS : ERROR_WRITE_FAULT;
+  return GetLastError();
+#else
+  int rc;
+  ssize_t written;
+  do {
+    written = pwrite(fd, buf, bytes, offset);
+    if (likely(bytes == (size_t)written))
+      return MDB_SUCCESS;
+    rc = errno;
+  } while (rc == EINTR);
+  return (written < 0) ? rc : EIO /* Use which error code (ENOSPC)? */;
+#endif
+}
+
+int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov, int iovcnt,
+                 off_t offset, size_t expected_written) {
+#if defined(_WIN32) || defined(_WIN64)
+  size_t written = 0;
+  for (int i = 0; i > iovcnt; ++i) {
+    int rc = mdbx_pwrite(fd, iov[i].iov_base, iov[i].iov_len, offset);
+    if (unlikely(rc != MDB_SUCCESS))
+      return rc;
+    written += iov[i].iov_len;
+    offset += iov[i].iov_len;
+  }
+  return (expected_written == written) ? MDB_SUCCESS : ERROR_WRITE_FAULT;
+#else
+  int rc;
+  ssize_t written;
+  do {
+    written = pwritev(fd, iov, iovcnt, offset);
+    if (likely(expected_written == (size_t)written))
+      return MDB_SUCCESS;
+    rc = errno;
+  } while (rc == EINTR);
+  return (written < 0) ? rc : EIO /* Use which error code? */;
+#endif
+}
+
+int mdbx_write(mdbx_filehandle_t fd, const void *buf, size_t bytes) {
+#ifdef SIGPIPE
+  sigset_t set, old;
+  sigemptyset(&set);
+  sigaddset(&set, SIGPIPE);
+  int rc = rc = pthread_sigmask(SIG_BLOCK, &set, &old);
+  if (rc != 0)
+    return rc;
+#endif
+
+  const char *ptr = buf;
+  for (;;) {
+    size_t chunk = (MAX_WRITE < bytes) ? MAX_WRITE : bytes;
+#if defined(_WIN32) || defined(_WIN64)
+    DWORD written;
+    if (unlikely(!WriteFile(fd, ptr, (DWORD)chunk, &written, NULL)))
+      return GetLastError();
+#else
+    ssize_t written = write(fd, ptr, chunk);
+    if (written < 0) {
+      int rc = errno;
+#ifdef SIGPIPE
+      if (rc == EPIPE) {
+        /* Collect the pending SIGPIPE, otherwise at least OS X
+         * gives it to the process on thread-exit (ITS#8504).
+         */
+        int tmp;
+        sigwait(&set, &tmp);
+        written = 0;
+        continue;
+      }
+      pthread_sigmask(SIG_SETMASK, &old, NULL);
+#endif
+      return rc;
+    }
+#endif
+    if (likely(bytes == (size_t)written)) {
+#ifdef SIGPIPE
+      pthread_sigmask(SIG_SETMASK, &old, NULL);
+#endif
+      return MDB_SUCCESS;
+    }
+    ptr += written;
+    bytes -= written;
+  }
+}
+
+int mdbx_filesync(mdbx_filehandle_t fd, bool syncmeta) {
+#if defined(_WIN32) || defined(_WIN64)
+  (void)syncmeta;
+  return FlushFileBuffers(fd) ? 0 : -1;
+#elif __GLIBC_PREREQ(2, 16) || _BSD_SOURCE || _XOPEN_SOURCE ||                 \
+    (__GLIBC_PREREQ(2, 8) && _POSIX_C_SOURCE >= 200112L)
+#if _POSIX_C_SOURCE >= 199309L || _XOPEN_SOURCE >= 500 ||                      \
+    defined(_POSIX_SYNCHRONIZED_IO)
+  if (!syncmeta)
+    return (fdatasync(fd) == 0) ? MDB_SUCCESS : errno;
+#endif
+  (void)syncmeta;
+  return (fsync(fd) == 0) ? MDB_SUCCESS : errno;
+#else
+#error FIXME
+#endif
+}
+
+int mdbx_filesize(mdbx_filehandle_t fd, off_t *length) {
+#if defined(_WIN32) || defined(_WIN64)
+  BY_HANDLE_FILE_INFORMATION info;
+  if (!GetFileInformationByHandle(fd, &info))
+    return GetLastError();
+  *length = info.nFileSizeLow | (uint64_t)info.nFileIndexHigh << 32;
+#else
+  struct stat st;
+
+  if (fstat(fd, &st))
+    return errno;
+
+  *length = st.st_size;
+#endif
+  return MDB_SUCCESS;
+}
+
+int mdbx_ftruncate(mdbx_filehandle_t fd, off_t length) {
+#if defined(_WIN32) || defined(_WIN64)
+  LARGE_INTEGER li;
+  li.QuadPart = length;
+  return (SetFilePointerEx(fd, li, NULL, FILE_BEGIN) && SetEndOfFile(fd))
+             ? MDB_SUCCESS
+             : GetLastError();
+#else
+  return ftruncate(fd, length) == 0 ? MDB_SUCCESS : errno;
+#endif
+}
+
+/*----------------------------------------------------------------------------*/
+
+int mdbx_thread_key_create(mdbx_thread_key_t *key) {
+#if defined(_WIN32) || defined(_WIN64)
+  *key = TlsAlloc();
+  return (*key != TLS_OUT_OF_INDEXES) ? MDB_SUCCESS : GetLastError();
+#else
+  return pthread_key_create(key, mdbx_rthc_dtor);
+#endif
+}
+
+void mdbx_thread_key_delete(mdbx_thread_key_t key) {
+#if defined(_WIN32) || defined(_WIN64)
+  mdbx_ensure(NULL, TlsFree(key));
+#else
+  mdbx_ensure(NULL, pthread_key_delete(key) == 0);
+#endif
+}
+
+void *mdbx_thread_rthc_get(mdbx_thread_key_t key) {
+#if defined(_WIN32) || defined(_WIN64)
+  return TlsGetValue(key);
+#else
+  return pthread_getspecific(key);
+#endif
+}
+
+void mdbx_thread_rthc_set(mdbx_thread_key_t key, const void *value) {
+#if defined(_WIN32) || defined(_WIN64)
+  mdbx_ensure(NULL, TlsSetValue(key, (void *)value));
+#else
+  mdbx_ensure(NULL, pthread_setspecific(key, value) == 0);
+#endif
+}
+
+mdbx_tid_t mdbx_thread_self(void) {
+#if defined(_WIN32) || defined(_WIN64)
+  return GetCurrentThreadId();
+#else
+  return pthread_self();
+#endif
+}
+
+int mdbx_thread_create(mdbx_thread_t *thread,
+                       THREAD_RESULT(THREAD_CALL *start_routine)(void *),
+                       void *arg) {
+#if defined(_WIN32) || defined(_WIN64)
+  *thread = CreateThread(NULL, 0, start_routine, arg, 0, NULL);
+  return *thread ? MDB_SUCCESS : GetLastError();
+#else
+  return pthread_create(thread, NULL, start_routine, arg);
+#endif
+}
+
+int mdbx_thread_join(mdbx_thread_t thread) {
+#if defined(_WIN32) || defined(_WIN64)
+  DWORD code = WaitForSingleObject(thread, INFINITE);
+  return waitfor2errcode(code);
+#else
+  void *unused_retval = &unused_retval;
+  return pthread_join(thread, &unused_retval);
+#endif
+}
+
+/*----------------------------------------------------------------------------*/
+
+int mdbx_msync(void *addr, size_t length, int async) {
+#if defined(_WIN32) || defined(_WIN64)
+  if (async)
+    return MDB_SUCCESS;
+  return FlushViewOfFile(addr, length) ? 0 : GetLastError();
+#else
+  return (msync(addr, length, async ? MS_ASYNC : MS_SYNC) == 0) ? MDB_SUCCESS
+                                                                : errno;
+#endif
+}
+
+int mdbx_mremap_size(void **address, size_t old_size, size_t new_size) {
+#if defined(_WIN32) || defined(_WIN64)
+  *address = MAP_FAILED;
+  (void)old_size;
+  (void)new_size;
+  return ERROR_NOT_SUPPORTED;
+#else
+  *address = mremap(*address, old_size, new_size, 0, address);
+  return (*address != MAP_FAILED) ? MDB_SUCCESS : errno;
+#endif
+}
+
+int mdbx_mmap(void **address, size_t length, int rw, mdbx_filehandle_t fd) {
+#if defined(_WIN32) || defined(_WIN64)
+  HANDLE h = CreateFileMapping(fd, NULL, rw ? PAGE_READWRITE : PAGE_READONLY,
+                               HIGH_DWORD(length), (DWORD)length, NULL);
+  if (!h)
+    return GetLastError();
+  *address = MapViewOfFileEx(h, rw ? FILE_MAP_WRITE : FILE_MAP_READ, 0, 0,
+                             length, *address);
+  int rc = (*address != MAP_FAILED) ? MDB_SUCCESS : GetLastError();
+  CloseHandle(h);
+  return rc;
+#else
+  *address = mmap(address, length, rw ? PROT_READ | PROT_WRITE : PROT_READ,
+                  MAP_SHARED, fd, 0);
+  return (*address != MAP_FAILED) ? MDB_SUCCESS : errno;
+#endif
+}
+
+int mdbx_munmap(void *address, size_t length) {
+#if defined(_WIN32) || defined(_WIN64)
+  (void)length;
+  return UnmapViewOfFile(address) ? MDB_SUCCESS : GetLastError();
+#else
+  return (munmap(address, length) == 0) ? MDB_SUCCESS : errno;
+#endif
+}
+
+int mdbx_mlock(const void *address, size_t length) {
+#if defined(_WIN32) || defined(_WIN64)
+  return VirtualLock((void *)address, length) ? MDB_SUCCESS : GetLastError();
+#else
+  return (mlock(address, length) == 0) ? MDB_SUCCESS : errno;
+#endif
+}

src/osal.h

@@ -0,0 +1,423 @@
+/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
+
+/*
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#pragma once
+
+#ifdef _MSC_VER
+#pragma warning(push, 1)
+#pragma warning(disable : 4530) /* C++ exception handler used, but             \
+                                    unwind semantics are not enabled. Specify  \
+                                    /EHsc */
+#pragma warning(disable : 4577) /* 'noexcept' used with no exception           \
+                                    handling mode specified; termination on    \
+                                    exception is not guaranteed. Specify /EHsc \
+                                    */
+#endif                          /* _MSC_VER (warnings) */
+
+#include <inttypes.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <malloc.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+
+#ifndef _POSIX_C_SOURCE
+#ifdef _POSIX_SOURCE
+#define _POSIX_C_SOURCE 1
+#else
+#define _POSIX_C_SOURCE 0
+#endif
+#endif
+
+#ifndef _XOPEN_SOURCE
+#define _XOPEN_SOURCE 0
+#endif
+
+#if defined(_WIN32) || defined(_WIN64)
+#include <windows.h>
+#include <winnt.h>
+#define HAVE_SYS_STAT_H
+#define HAVE_SYS_TYPES_H
+typedef HANDLE mdbx_mutex_t;
+typedef HANDLE mdbx_cond_t;
+typedef HANDLE mdbx_thread_t;
+typedef unsigned mdbx_thread_key_t;
+typedef SSIZE_T ssize_t;
+#define MAP_FAILED NULL
+#define HIGH_DWORD(v) ((DWORD)((sizeof(v) > 4) ? ((uint64_t)(v) >> 32) : 0))
+#define THREAD_CALL WINAPI
+#define THREAD_RESULT DWORD
+#else
+#include <pthread.h>
+#include <sys/mman.h>
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/uio.h>
+#include <unistd.h>
+typedef pthread_mutex_t mdbx_mutex_t;
+typedef pthread_cond_t mdbx_cond_t;
+typedef pthread_t mdbx_thread_t;
+typedef pthread_key_t mdbx_thread_key_t;
+#define INVALID_HANDLE_VALUE (-1)
+#define THREAD_CALL
+#define THREAD_RESULT void *
+#endif /* Platform */
+
+#ifndef SSIZE_MAX
+#define SSIZE_MAX INTPTR_MAX
+#endif
+
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_FILE_H
+#include <sys/file.h>
+#endif
+
+/*----------------------------------------------------------------------------*/
+
+#ifdef _MSC_VER
+
+#if _MSC_FULL_VER < 190024215
+#if _MSC_FULL_VER < 180040629 && defined(_M_IX86)
+#error Please use Visual Studio 2015 (MSC 19.0) or newer for 32-bit target.
+#else
+#pragma message(                                                               \
+    "It is recommended to use Visual Studio 2015 (MSC 19.0) or newer.")
+#endif
+#endif
+
+#include <intrin.h>
+
+#elif __GNUC_PREREQ(4, 4) || defined(__clang__)
+#if defined(__i386__) || defined(__x86_64__)
+#include <cpuid.h>
+#include <x86intrin.h>
+#endif
+#elif defined(__INTEL_COMPILER)
+#include <intrin.h>
+#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
+#include <mbarrier.h>
+#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
+    (defined(HP_IA64) || defined(__ia64))
+#include <machine/sys/inline.h>
+#elif defined(__IBMC__) && defined(__powerpc)
+#include <atomic.h>
+#elif defined(_AIX)
+#include <builtins.h>
+#include <sys/atomic_op.h>
+#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
+#include <c_asm.h>
+#include <machine/builtins.h>
+#elif defined(__MWERKS__)
+/* CodeWarrior - troubles ? */
+#pragma gcc_extensions
+#elif defined(__SNC__)
+/* Sony PS3 - troubles ? */
+#else
+#error Unknown C compiler, please use GNU C 5.x or newer
+#endif /* Compiler */
+
+/*----------------------------------------------------------------------------*/
+/* Byteorder */
+
+#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) ||           \
+    !defined(__ORDER_BIG_ENDIAN__)
+
+#if defined(HAVE_ENDIAN_H)
+#include <endian.h>
+#elif defined(HAVE_SYS_PARAM_H)
+#include <sys/param.h> /* for endianness */
+#elif defined(HAVE_NETINET_IN_H) && defined(HAVE_RESOLV_H)
+#include <netinet/in.h>
+#include <resolv.h> /* defines BYTE_ORDER on HPUX and Solaris */
+#endif
+
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
+#if defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
+#define __ORDER_LITTLE_ENDIAN__ __LITTLE_ENDIAN
+#define __ORDER_BIG_ENDIAN__ __BIG_ENDIAN
+#define __BYTE_ORDER__ __BYTE_ORDER
+#else
+#define __ORDER_LITTLE_ENDIAN__ 1234
+#define __ORDER_BIG_ENDIAN__ 4321
+#if defined(__LITTLE_ENDIAN__) || defined(_LITTLE_ENDIAN) ||                   \
+    defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) ||    \
+    defined(__MIPSEL__) || defined(_MIPSEL) || defined(__MIPSEL) ||            \
+    defined(__i386) || defined(__x86_64__) || defined(_M_IX86) ||              \
+    defined(_M_X64) || defined(i386) || defined(_X86_) || defined(__i386__) || \
+    defined(_X86_64_) || defined(_M_ARM) || defined(__e2k__)
+#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
+#elif defined(__BIG_ENDIAN__) || defined(_BIG_ENDIAN) || defined(__ARMEB__) || \
+    defined(__THUMBEB__) || defined(__AARCH64EB__) || defined(__MIPSEB__) ||   \
+    defined(_MIPSEB) || defined(__MIPSEB)
+#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
+#else
+#error __BYTE_ORDER__ should be defined.
+#endif
+#endif
+#endif
+
+#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__ &&                               \
+    __BYTE_ORDER__ != __ORDER_BIG_ENDIAN__
+#error Unsupported byte order.
+#endif
+
+/*----------------------------------------------------------------------------*/
+/* Cache coherence */
+
+#if defined(__i386__) || defined(__x86_64__) || defined(_M_AMD64) ||           \
+    defined(_M_IX86) || defined(__i386) || defined(__amd64) ||                 \
+    defined(i386) || defined(__x86_64) || defined(_AMD64_) || defined(_M_X64)
+#define MDBX_CACHE_IS_COHERENT 1
+#elif defined(__hppa) || defined(__hppa__)
+#define MDBX_CACHE_IS_COHERENT 1
+#endif
+
+#ifndef MDBX_CACHE_IS_COHERENT
+#define MDBX_CACHE_IS_COHERENT 0
+#endif
+
+#ifndef MDBX_CACHELINE_SIZE
+#if defined(SYSTEM_CACHE_ALIGNMENT_SIZE)
+#define MDBX_CACHELINE_SIZE SYSTEM_CACHE_ALIGNMENT_SIZE
+#elif defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
+#define MDBX_CACHELINE_SIZE 128
+#else
+#define MDBX_CACHELINE_SIZE 64
+#endif
+#endif /* MDBX_CACHELINE_SIZE */
+
+#ifndef __cache_aligned
+#define __cache_aligned __aligned(MDBX_CACHELINE_SIZE)
+#endif
+
+/*----------------------------------------------------------------------------*/
+/* Memory/Compiler barriers */
+
+static __inline void mdbx_compiler_barrier(void) {
+#if defined(__clang__) || defined(__GNUC__)
+  __asm__ __volatile__("" ::: "memory");
+#elif defined(_MSC_VER)
+  _ReadWriteBarrier();
+#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
+  __memory_barrier();
+  if (type > MDBX_BARRIER_COMPILER)
+#if defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
+    __mf();
+#elif defined(__i386__) || defined(__x86_64__)
+    _mm_mfence();
+#else
+#error "Unknown target for Intel Compiler, please report to us."
+#endif
+#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
+  __compiler_barrier();
+#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
+    (defined(HP_IA64) || defined(__ia64))
+  _Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
+#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
+    defined(__ppc64__) || defined(__powerpc64__)
+  __fence();
+#else
+#error "Could not guess the kind of compiler, please report to us."
+#endif
+}
+
+static __inline void mdbx_memory_barrier(void) {
+#if __has_extension(c_atomic) || __has_extension(cxx_atomic)
+  __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
+#elif defined(__ATOMIC_SEQ_CST)
+  __atomic_thread_fence(__ATOMIC_SEQ_CST);
+#elif defined(__clang__) || defined(__GNUC__)
+  __sync_synchronize();
+#elif defined(_MSC_VER)
+  MemoryBarrier();
+#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
+#if defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
+  __mf();
+#elif defined(__i386__) || defined(__x86_64__)
+  _mm_mfence();
+#else
+#error "Unknown target for Intel Compiler, please report to us."
+#endif
+#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
+  __machine_rw_barrier();
+#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
+    (defined(HP_IA64) || defined(__ia64))
+  _Asm_mf();
+#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
+    defined(__ppc64__) || defined(__powerpc64__)
+  __lwsync();
+#else
+#error "Could not guess the kind of compiler, please report to us."
+#endif
+}
+
+#if MDBX_CACHE_IS_COHERENT
+#define mdbx_coherent_barrier() mdbx_compiler_barrier()
+#else
+#define mdbx_coherent_barrier() mdbx_memory_barrier()
+#endif
+
+#if defined(__mips) && defined(__linux)
+/* Only MIPS has explicit cache control */
+#include <asm/cachectl.h>
+#endif
+
+static __inline void mdbx_invalidate_cache(void *addr, size_t nbytes) {
+  mdbx_coherent_barrier();
+#if defined(__mips) && defined(__linux)
+  /* MIPS has cache coherency issues.
+   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
+  cacheflush(addr, nbytes, DCACHE);
+#elif defined(_M_MRX000) || defined(_MIPS_)
+#error "Sorry, cacheflush() for MIPS not implemented"
+#else
+  /* LY: assume no relevant mmap/dcache issues. */
+  (void)addr;
+  (void)nbytes;
+#endif
+}
+
+/*----------------------------------------------------------------------------*/
+
+/* max bytes to write in one call */
+#define MAX_WRITE (0x80000000U >> (sizeof(ssize_t) == 4))
+
+/* Get the size of a memory page for the system.
+ * This is the basic size that the platform's memory manager uses, and is
+ * fundamental to the use of memory-mapped files. */
+static __inline size_t mdbx_syspagesize(void) {
+#if defined(_WIN32) || defined(_WIN64)
+  SYSTEM_INFO si;
+  GetSystemInfo(&si);
+  return si.dwPageSize;
+#else
+  return sysconf(_SC_PAGE_SIZE);
+#endif
+}
+
+static __inline char *mdbx_strdup(const char *str) {
+#ifdef _MSC_VER
+  return _strdup(str);
+#else
+  return strdup(str);
+#endif
+}
+
+int mdbx_memalign_alloc(size_t alignment, size_t bytes, void **result);
+void mdbx_memalign_free(void *ptr);
+
+int mdbx_mutex_init(mdbx_mutex_t *mutex);
+int mdbx_mutex_destroy(mdbx_mutex_t *mutex);
+int mdbx_mutex_lock(mdbx_mutex_t *mutex);
+int mdbx_mutex_unlock(mdbx_mutex_t *mutex);
+
+int mdbx_cond_init(mdbx_cond_t *cond);
+int mdbx_cond_destroy(mdbx_cond_t *cond);
+int mdbx_cond_signal(mdbx_cond_t *cond);
+int mdbx_cond_wait(mdbx_cond_t *cond, mdbx_mutex_t *mutex);
+
+int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov, int iovcnt,
+                 off_t offset, size_t expected_written);
+int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count, off_t offset);
+int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf, size_t count,
+                off_t offset);
+int mdbx_write(mdbx_filehandle_t fd, const void *buf, size_t count);
+
+int mdbx_msync(void *addr, size_t length, int async);
+
+int mdbx_thread_create(mdbx_thread_t *thread,
+                       THREAD_RESULT(THREAD_CALL *start_routine)(void *),
+                       void *arg);
+int mdbx_thread_join(mdbx_thread_t thread);
+mdbx_tid_t mdbx_thread_self(void);
+int mdbx_thread_key_create(mdbx_thread_key_t *key);
+void mdbx_thread_key_delete(mdbx_thread_key_t key);
+void *mdbx_thread_rthc_get(mdbx_thread_key_t key);
+void mdbx_thread_rthc_set(mdbx_thread_key_t key, const void *value);
+
+int mdbx_filesync(mdbx_filehandle_t fd, bool syncmeta);
+int mdbx_ftruncate(mdbx_filehandle_t fd, off_t length);
+int mdbx_filesize(mdbx_filehandle_t fd, off_t *length);
+int mdbx_openfile(const char *pathname, int flags, mode_t mode,
+                  mdbx_filehandle_t *fd);
+int mdbx_closefile(mdbx_filehandle_t fd);
+
+int mdbx_mremap_size(void **address, size_t old_size, size_t new_size);
+int mdbx_mmap(void **address, size_t length, int rw, mdbx_filehandle_t fd);
+int mdbx_munmap(void *address, size_t length);
+int mdbx_mlock(const void *address, size_t length);
+
+static __inline mdbx_pid_t mdbx_getpid(void) {
+#if defined(_WIN32) || defined(_WIN64)
+  return GetCurrentProcessId();
+#else
+  return getpid();
+#endif
+}
+
+/*----------------------------------------------------------------------------*/
+
+#ifndef mdbx_assert_fail
+void mdbx_assert_fail(MDB_env *env, const char *msg, const char *func,
+                      int line);
+#endif /* mdbx_assert_fail */
+
+#if __GLIBC_PREREQ(2, 1)
+#define mdbx_asprintf asprintf
+#else
+int mdbx_asprintf(char **strp, const char *fmt, ...);
+#endif
+
+/*----------------------------------------------------------------------------*/
+
+#if defined(_WIN32) || defined(_WIN64)
+#undef MDBX_OSAL_LOCK
+#define MDBX_OSAL_LOCK_SIGN MDBX_TETRAD('f', 'l', 'c', 'k')
+#else
+#define MDBX_OSAL_LOCK pthread_mutex_t
+#define MDBX_OSAL_LOCK_SIGN MDBX_TETRAD('P', 'T', 'M', 'X')
+#endif
+
+int mdbx_lck_init(MDB_env *env);
+
+int mdbx_lck_seize(MDB_env *env);
+int mdbx_lck_downgrade(MDB_env *env);
+void mdbx_lck_destroy(MDB_env *env);
+
+int mdbx_rdt_lock(MDB_env *env);
+void mdbx_rdt_unlock(MDB_env *env);
+
+int mdbx_txn_lock(MDB_env *env);
+void mdbx_txn_unlock(MDB_env *env);
+
+int mdbx_rpid_set(MDB_env *env);
+int mdbx_rpid_clear(MDB_env *env);
+int mdbx_rpid_check(MDB_env *env, mdbx_pid_t pid);

src/reopen.h

@@ -1,236 +0,0 @@
-/*
- * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>.
- * Copyright 2015,2016 Peter-Service R&D LLC.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-#pragma once
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#ifndef __CLANG_PREREQ
-#	ifdef __clang__
-#		define __CLANG_PREREQ(maj,min) \
-			((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-#	else
-#		define __CLANG_PREREQ(maj,min) (0)
-#	endif
-#endif /* __CLANG_PREREQ */
-
-#ifndef __has_attribute
-#	define __has_attribute(x) (0)
-#endif
-
-#if !defined(__thread) && (defined(_MSC_VER) || defined(__DMC__))
-#	define __thread __declspec(thread)
-#endif
-
-#ifndef __forceinline
-#	if defined(__GNUC__) || defined(__clang__)
-#		define __forceinline __inline __attribute__((always_inline))
-#	elif ! defined(_MSC_VER)
-#		define __forceinline
-#	endif
-#endif /* __forceinline */
-
-#ifndef __noinline
-#	if defined(__GNUC__) || defined(__clang__)
-#		define __noinline __attribute__((noinline))
-#	elif defined(_MSC_VER)
-#		define __noinline __declspec(noinline)
-#	endif
-#endif /* __noinline */
-
-#ifndef __must_check_result
-#	if defined(__GNUC__) || defined(__clang__)
-#		define __must_check_result __attribute__((warn_unused_result))
-#	else
-#		define __must_check_result
-#	endif
-#endif /* __must_check_result */
-
-#ifndef __hot
-#	if defined(__OPTIMIZE__) && (defined(__GNUC__) && !defined(__clang__))
-#		define __hot __attribute__((hot, optimize("O3")))
-#	elif defined(__GNUC__)
-		/* cland case, just put frequently used functions in separate section */
-#		define __hot __attribute__((section("text.hot")))
-#	else
-#		define __hot
-#	endif
-#endif /* __hot */
-
-#ifndef __cold
-#	if defined(__OPTIMIZE__) && (defined(__GNUC__) && !defined(__clang__))
-#		define __cold __attribute__((cold, optimize("Os")))
-#	elif defined(__GNUC__)
-		/* cland case, just put infrequently used functions in separate section */
-#		define __cold __attribute__((section("text.unlikely")))
-#	else
-#		define __cold
-#	endif
-#endif /* __cold */
-
-#ifndef __flatten
-#	if defined(__OPTIMIZE__) && (defined(__GNUC__) || defined(__clang__))
-#		define __flatten __attribute__((flatten))
-#	else
-#		define __flatten
-#	endif
-#endif /* __flatten */
-
-#ifndef __aligned
-#	if defined(__GNUC__) || defined(__clang__)
-#		define __aligned(N) __attribute__((aligned(N)))
-#	elif defined(__MSC_VER)
-#		define __aligned(N) __declspec(align(N))
-#	else
-#		define __aligned(N)
-#	endif
-#endif /* __align */
-
-#ifndef __noreturn
-#	if defined(__GNUC__) || defined(__clang__)
-#		define __noreturn __attribute__((noreturn))
-#	elif defined(__MSC_VER)
-#		define __noreturn __declspec(noreturn)
-#	else
-#		define __noreturn
-#	endif
-#endif
-
-#ifndef __nothrow
-#	if defined(__GNUC__) || defined(__clang__)
-#		define __nothrow __attribute__((nothrow))
-#	elif defined(__MSC_VER)
-#		define __nothrow __declspec(nothrow)
-#	else
-#		define __nothrow
-#	endif
-#endif
-
-#ifndef CACHELINE_SIZE
-#	if defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#		define CACHELINE_SIZE 128
-#	else
-#		define CACHELINE_SIZE 64
-#	endif
-#endif
-
-#ifndef __cache_aligned
-#	define __cache_aligned __aligned(CACHELINE_SIZE)
-#endif
-
-#ifndef likely
-#	if defined(__GNUC__) || defined(__clang__)
-#		ifdef __cplusplus
-			/* LY: workaround for "pretty" boost */
-			static __inline __attribute__((always_inline))
-				bool likely(bool cond) { return __builtin_expect(cond, 1); }
-#		else
-#			define likely(cond) __builtin_expect(!!(cond), 1)
-#		endif
-#	else
-#		define likely(x) (x)
-#	endif
-#endif /* likely */
-
-#ifndef unlikely
-#	if defined(__GNUC__) || defined(__clang__)
-#		ifdef __cplusplus
-			/* LY: workaround for "pretty" boost */
-			static __inline __attribute__((always_inline))
-				bool unlikely(bool cond) { return __builtin_expect(cond, 0); }
-#		else
-#			define unlikely(cond) __builtin_expect(!!(cond), 0)
-#		endif
-#	else
-#		define unlikely(x) (x)
-#	endif
-#endif /* unlikely */
-
-#ifndef __extern_C
-#    ifdef __cplusplus
-#        define __extern_C extern "C"
-#    else
-#        define __extern_C
-#    endif
-#endif
-
-#ifndef __noop
-#    define __noop() do {} while (0)
-#endif
-
-/* -------------------------------------------------------------------------- */
-
-#include <assert.h>
-
-/* Prototype should match libc runtime. ISO POSIX (2003) & LSB 3.1 */
-__extern_C void __assert_fail(
-		const char* assertion,
-		const char* file,
-		unsigned line,
-		const char* function) __nothrow __noreturn;
-
-/* -------------------------------------------------------------------------- */
-
-#if defined(HAVE_VALGRIND) || defined(USE_VALGRIND)
-	/* Get debugging help from Valgrind */
-#	include <valgrind/memcheck.h>
-#	ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
-		/* LY: available since Valgrind 3.10 */
-#		define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#		define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#	endif
-#else
-#	define VALGRIND_CREATE_MEMPOOL(h,r,z)
-#	define VALGRIND_DESTROY_MEMPOOL(h)
-#	define VALGRIND_MEMPOOL_TRIM(h,a,s)
-#	define VALGRIND_MEMPOOL_ALLOC(h,a,s)
-#	define VALGRIND_MEMPOOL_FREE(h,a)
-#	define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
-#	define VALGRIND_MAKE_MEM_NOACCESS(a,s)
-#	define VALGRIND_MAKE_MEM_DEFINED(a,s)
-#	define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
-#	define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#	define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#	define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
-#	define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
-#endif /* ! USE_VALGRIND */
-
-#if defined(__has_feature)
-#	if __has_feature(thread_sanitizer)
-#		define __SANITIZE_THREAD__ 1
-#	endif
-#endif
-
-#ifdef __SANITIZE_THREAD__
-#	define ATTRIBUTE_NO_SANITIZE_THREAD __attribute__((no_sanitize_thread, noinline))
-#else
-#	define ATTRIBUTE_NO_SANITIZE_THREAD
-#endif
-
-#if defined(__has_feature)
-#	if __has_feature(address_sanitizer)
-#		define __SANITIZE_ADDRESS__ 1
-#	endif
-#endif
-
-#ifdef __SANITIZE_ADDRESS__
-#	include <sanitizer/asan_interface.h>
-#	define ATTRIBUTE_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address, noinline))
-#else
-#	define ASAN_POISON_MEMORY_REGION(addr, size) \
-		((void)(addr), (void)(size))
-#	define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
-		((void)(addr), (void)(size))
-#	define ATTRIBUTE_NO_SANITIZE_ADDRESS
-#endif /* __SANITIZE_ADDRESS__ */

src/tools/mdbx_chk.c

@@ -1,24 +1,17 @@
 /* mdbx_chk.c - memory-mapped database check tool */
 
 /*
- * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
- * Copyright 2015,2016 Peter-Service R&D LLC.
+ * and other libmdbx authors: please see AUTHORS file.
+ * All rights reserved.
  *
- * This file is part of libmdbx.
+ * Redistribution and use in source and binary forms, with or without
- *
+ * modification, are permitted only as authorized by the OpenLDAP
- * libmdbx is free software; you can redistribute it and/or modify it under
+ * Public License.
- * the terms of the GNU Affero General Public License as published by
- * the Free Software Foundation; either version 3 of the License, or
- * (at your option) any later version.
- *
- * libmdbx is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
  */
 
 #include <ctype.h>
@@ -32,8 +25,8 @@
 #include <time.h>
 #include <unistd.h>
 
-#include "mdbx.h"
+#include "../../mdbx.h"
-#include "midl.h"
+#include "../midl.h"
 
 typedef struct flagbit {
   int bit;
@@ -624,7 +617,7 @@ int main(int argc, char *argv[]) {
   while ((i = getopt(argc, argv, "Vvqnwcds:")) != EOF) {
     switch (i) {
     case 'V':
-      printf("%s\n", MDB_VERSION_STRING);
+      printf("%s\n", MDBX_VERSION_STRING);
       exit(EXIT_SUCCESS);
       break;
     case 'v':

src/tools/mdbx_copy.c

@@ -1,9 +1,8 @@
 /* mdbx_copy.c - memory-mapped database backup tool */
 
 /*
- * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
- * Copyright 2012-2017 Howard Chu, Symas Corp.
+ * and other libmdbx authors: please see AUTHORS file.
- * Copyright 2015,2016 Peter-Service R&D LLC.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -15,10 +14,11 @@
  * <http://www.OpenLDAP.org/license.html>.
  */
 
-#include "mdbx.h"
+#include "../../mdbx.h"
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 static void sighandle(int sig) { (void)sig; }
 
@@ -35,7 +35,7 @@ int main(int argc, char *argv[]) {
     else if (argv[1][1] == 'c' && argv[1][2] == '\0')
       cpflags |= MDB_CP_COMPACT;
     else if (argv[1][1] == 'V' && argv[1][2] == '\0') {
-      printf("%s\n", MDB_VERSION_STRING);
+      printf("%s\n", MDBX_VERSION_STRING);
       exit(0);
     } else
       argc = 0;

src/tools/mdbx_dump.c

@@ -1,9 +1,8 @@
 /* mdbx_dump.c - memory-mapped database dump tool */
 
 /*
- * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
- * Copyright 2011-2017 Howard Chu, Symas Corp.
+ * and other libmdbx authors: please see AUTHORS file.
- * Copyright 2015,2016 Peter-Service R&D LLC.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -15,7 +14,7 @@
  * <http://www.OpenLDAP.org/license.html>.
  */
 
-#include "mdbx.h"
+#include "../../mdbx.h"
 #include <ctype.h>
 #include <errno.h>
 #include <signal.h>
@@ -178,7 +177,7 @@ int main(int argc, char *argv[]) {
   while ((i = getopt(argc, argv, "af:lnps:V")) != EOF) {
     switch (i) {
     case 'V':
-      printf("%s\n", MDB_VERSION_STRING);
+      printf("%s\n", MDBX_VERSION_STRING);
       exit(0);
       break;
     case 'l':

src/tools/mdbx_load.c

@@ -1,9 +1,8 @@
 /* mdbx_load.c - memory-mapped database load tool */
 
 /*
- * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
- * Copyright 2011-2017 Howard Chu, Symas Corp.
+ * and other libmdbx authors: please see AUTHORS file.
- * Copyright 2015,2016 Peter-Service R&D LLC.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -15,7 +14,7 @@
  * <http://www.OpenLDAP.org/license.html>.
  */
 
-#include "mdbx.h"
+#include "../../mdbx.h"
 #include <ctype.h>
 #include <errno.h>
 #include <stdio.h>
@@ -314,7 +313,7 @@ int main(int argc, char *argv[]) {
   while ((i = getopt(argc, argv, "f:ns:NTV")) != EOF) {
     switch (i) {
     case 'V':
-      printf("%s\n", MDB_VERSION_STRING);
+      printf("%s\n", MDBX_VERSION_STRING);
       exit(0);
       break;
     case 'f':
@@ -365,8 +364,10 @@ int main(int argc, char *argv[]) {
   if (info.me_mapsize)
     mdbx_env_set_mapsize(env, info.me_mapsize);
 
+#ifdef MDB_FIXEDMAP
   if (info.me_mapaddr)
     envflags |= MDB_FIXEDMAP;
+#endif
 
   rc = mdbx_env_open(env, envname, envflags, 0664);
   if (rc) {

src/tools/mdbx_stat.c

@@ -1,9 +1,8 @@
 /* mdbx_stat.c - memory-mapped database status tool */
 
 /*
- * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>.
+ * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
- * Copyright 2011-2017 Howard Chu, Symas Corp.
+ * and other libmdbx authors: please see AUTHORS file.
- * Copyright 2015,2016 Peter-Service R&D LLC.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -15,7 +14,7 @@
  * <http://www.OpenLDAP.org/license.html>.
  */
 
-#include "mdbx.h"
+#include "../../mdbx.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -65,7 +64,7 @@ int main(int argc, char *argv[]) {
   while ((i = getopt(argc, argv, "Vaefnrs:")) != EOF) {
     switch (i) {
     case 'V':
-      printf("%s\n", MDB_VERSION_STRING);
+      printf("%s\n", MDBX_VERSION_STRING);
       exit(0);
       break;
     case 'a':

test/test0.c

@@ -15,7 +15,7 @@
  * <http://www.OpenLDAP.org/license.html>.
  */
 
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -79,7 +79,7 @@ int main(int argc, char *argv[]) {
 
   E(stat("/proc/self/exe", &exe_stat) ? errno : 0);
   E(stat(DBPATH "/.", &db_stat) ? errno : 0);
-  env_oflags = MDB_FIXEDMAP | MDB_NOSYNC;
+  env_oflags = MDB_NOSYNC;
   if (major(db_stat.st_dev) != major(exe_stat.st_dev)) {
     /* LY: Assume running inside a CI-environment:
      *  1) don't use FIXEDMAP to avoid EBUSY in case collision,

test/test1.c

@@ -14,7 +14,7 @@
 
 /* Based on mtest2.c - memory-mapped database tester/toy */
 
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -65,7 +65,7 @@ int main(int argc, char *argv[]) {
 
   E(stat("/proc/self/exe", &exe_stat) ? errno : 0);
   E(stat(DBPATH "/.", &db_stat) ? errno : 0);
-  env_oflags = MDB_FIXEDMAP | MDB_NOSYNC;
+  env_oflags = MDB_NOSYNC;
   if (major(db_stat.st_dev) != major(exe_stat.st_dev)) {
     /* LY: Assume running inside a CI-environment:
      *  1) don't use FIXEDMAP to avoid EBUSY in case collision,

test/test2.c

@@ -17,7 +17,7 @@
 
 /* Just like mtest.c, but using a subDB instead of the main DB */
 
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -68,7 +68,7 @@ int main(int argc, char *argv[]) {
 
   E(stat("/proc/self/exe", &exe_stat) ? errno : 0);
   E(stat(DBPATH "/.", &db_stat) ? errno : 0);
-  env_oflags = MDB_FIXEDMAP | MDB_NOSYNC;
+  env_oflags = MDB_NOSYNC;
   if (major(db_stat.st_dev) != major(exe_stat.st_dev)) {
     /* LY: Assume running inside a CI-environment:
      *  1) don't use FIXEDMAP to avoid EBUSY in case collision,

test/test3.c

@@ -16,7 +16,7 @@
  */
 
 /* Tests for sorted duplicate DBs */
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -70,7 +70,7 @@ int main(int argc, char *argv[]) {
 
   E(stat("/proc/self/exe", &exe_stat) ? errno : 0);
   E(stat(DBPATH "/.", &db_stat) ? errno : 0);
-  env_oflags = MDB_FIXEDMAP | MDB_NOSYNC;
+  env_oflags = MDB_NOSYNC;
   if (major(db_stat.st_dev) != major(exe_stat.st_dev)) {
     /* LY: Assume running inside a CI-environment:
      *  1) don't use FIXEDMAP to avoid EBUSY in case collision,

test/test4.c

@@ -16,7 +16,7 @@
  */
 
 /* Tests for sorted duplicate DBs with fixed-size keys */
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -68,7 +68,7 @@ int main(int argc, char *argv[]) {
 
   E(stat("/proc/self/exe", &exe_stat) ? errno : 0);
   E(stat(DBPATH "/.", &db_stat) ? errno : 0);
-  env_oflags = MDB_FIXEDMAP | MDB_NOSYNC;
+  env_oflags = MDB_NOSYNC;
   if (major(db_stat.st_dev) != major(exe_stat.st_dev)) {
     /* LY: Assume running inside a CI-environment:
      *  1) don't use FIXEDMAP to avoid EBUSY in case collision,

test/test5.c

@@ -16,7 +16,7 @@
  */
 
 /* Tests for sorted duplicate DBs using cursor_put */
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -70,7 +70,7 @@ int main(int argc, char *argv[]) {
 
   E(stat("/proc/self/exe", &exe_stat) ? errno : 0);
   E(stat(DBPATH "/.", &db_stat) ? errno : 0);
-  env_oflags = MDB_FIXEDMAP | MDB_NOSYNC;
+  env_oflags = MDB_NOSYNC;
   if (major(db_stat.st_dev) != major(exe_stat.st_dev)) {
     /* LY: Assume running inside a CI-environment:
      *  1) don't use FIXEDMAP to avoid EBUSY in case collision,

test/test6.c

@@ -16,7 +16,7 @@
  */
 
 /* Tests for DB splits and merges */
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -61,7 +61,7 @@ int main(int argc, char *argv[]) {
 
   E(stat("/proc/self/exe", &exe_stat) ? errno : 0);
   E(stat(DBPATH "/.", &db_stat) ? errno : 0);
-  env_oflags = MDB_FIXEDMAP | MDB_NOSYNC;
+  env_oflags = MDB_NOSYNC;
   if (major(db_stat.st_dev) != major(exe_stat.st_dev)) {
     /* LY: Assume running inside a CI-environment:
      *  1) don't use FIXEDMAP to avoid EBUSY in case collision,

test/test_bench.c

@@ -22,7 +22,7 @@
 #include <time.h>
 #include <unistd.h>
 
-#include "mdbx.h"
+#include "../mdbx.h"
 
 #define E(expr) CHECK((rc = (expr)) == MDB_SUCCESS, #expr)
 #define RES(err, expr) ((rc = expr) == (err) || (CHECK(!rc, #expr), 0))

test/test_yota1.c

@@ -22,7 +22,7 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <assert.h>
 #include <limits.h>
 #include <stddef.h>

test/test_yota2.c

@@ -22,7 +22,7 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 
-#include "mdbx.h"
+#include "../mdbx.h"
 #include <assert.h>
 #include <limits.h>
 #include <stddef.h>