/* * Copyright 2015-2022 Leonid Yuriev * 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 * . */ #pragma once #ifdef MDBX_CONFIG_H #include MDBX_CONFIG_H #endif #define LIBMDBX_INTERNALS #ifdef xMDBX_TOOLS #define MDBX_DEPRECATED #endif /* xMDBX_TOOLS */ #ifdef xMDBX_ALLOY /* Amalgamated build */ #define MDBX_INTERNAL_FUNC static #define MDBX_INTERNAL_VAR static #else /* Non-amalgamated build */ #define MDBX_INTERNAL_FUNC #define MDBX_INTERNAL_VAR extern #endif /* xMDBX_ALLOY */ /** Disables using GNU/Linux libc extensions. * \ingroup build_option * \note This option couldn't be moved to the options.h since dependant * control macros/defined should be prepared before include the options.h */ #ifndef MDBX_DISABLE_GNU_SOURCE #define MDBX_DISABLE_GNU_SOURCE 0 #endif #if MDBX_DISABLE_GNU_SOURCE #undef _GNU_SOURCE #elif (defined(__linux__) || defined(__gnu_linux__)) && !defined(_GNU_SOURCE) #define _GNU_SOURCE #endif /* MDBX_DISABLE_GNU_SOURCE */ /*----------------------------------------------------------------------------*/ /* Should be defined before any includes */ #if !defined(_FILE_OFFSET_BITS) && !defined(__ANDROID_API__) && \ !defined(ANDROID) #define _FILE_OFFSET_BITS 64 #endif #ifdef __APPLE__ #define _DARWIN_C_SOURCE #endif #ifdef _MSC_VER #if _MSC_FULL_VER < 190024234 /* Actually libmdbx was not tested with compilers older than 19.00.24234 (Visual * Studio 2015 Update 3). But you could remove this #error and try to continue * at your own risk. In such case please don't rise up an issues related ONLY to * old compilers. * * NOTE: * Unfortunately, there are several different builds of "Visual Studio" that * are called "Visual Studio 2015 Update 3". * * The 190024234 is used here because it is minimal version of Visual Studio * that was used for build and testing libmdbx in recent years. Soon this * value will be increased to 19.0.24241.7, since build and testing using * "Visual Studio 2015" will be performed only at https://ci.appveyor.com. * * Please ask Microsoft (but not us) for information about version differences * and how to and where you can obtain the latest "Visual Studio 2015" build * with all fixes. */ #error \ "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required." #endif #ifndef _CRT_SECURE_NO_WARNINGS #define _CRT_SECURE_NO_WARNINGS #endif /* _CRT_SECURE_NO_WARNINGS */ #if _MSC_VER > 1800 #pragma warning(disable : 4464) /* relative include path contains '..' */ #endif #if _MSC_VER > 1913 #pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation... \ */ #endif #if _MSC_VER > 1914 #pragma warning( \ disable : 5105) /* winbase.h(9531): warning C5105: macro expansion \ producing 'defined' has undefined behavior */ #endif #pragma warning(disable : 4710) /* 'xyz': function not inlined */ #pragma warning(disable : 4711) /* function 'xyz' selected for automatic \ inline expansion */ #pragma warning( \ disable : 4201) /* nonstandard extension used : nameless struct / union */ #pragma warning(disable : 4702) /* unreachable code */ #pragma warning(disable : 4706) /* assignment within conditional expression */ #pragma warning(disable : 4127) /* conditional expression is constant */ #pragma warning(disable : 4324) /* 'xyz': structure was padded due to \ alignment specifier */ #pragma warning(disable : 4310) /* cast truncates constant value */ #pragma warning( \ disable : 4820) /* bytes padding added after data member for alignment */ #pragma warning(disable : 4548) /* expression before comma has no effect; \ expected expression with side - effect */ #pragma warning(disable : 4366) /* the result of the unary '&' operator may be \ unaligned */ #pragma warning(disable : 4200) /* nonstandard extension used: zero-sized \ array in struct/union */ #pragma warning(disable : 4204) /* nonstandard extension used: non-constant \ aggregate initializer */ #pragma warning( \ disable : 4505) /* unreferenced local function has been removed */ #endif /* _MSC_VER (warnings) */ #if defined(__GNUC__) && __GNUC__ < 9 #pragma GCC diagnostic ignored "-Wattributes" #endif /* GCC < 9 */ #if (defined(__MINGW__) || defined(__MINGW32__) || defined(__MINGW64__)) && \ !defined(__USE_MINGW_ANSI_STDIO) #define __USE_MINGW_ANSI_STDIO 1 #endif /* __USE_MINGW_ANSI_STDIO */ #include "../mdbx.h" #include "defs.h" #if defined(__GNUC__) && !__GNUC_PREREQ(4, 2) /* Actually libmdbx was not tested with compilers older than GCC 4.2. * But you could ignore this warning at your own risk. * In such case please don't rise up an issues related ONLY to old compilers. */ #warning "libmdbx required GCC >= 4.2" #endif #if defined(__clang__) && !__CLANG_PREREQ(3, 8) /* Actually libmdbx was not tested with CLANG older than 3.8. * But you could ignore this warning at your own risk. * In such case please don't rise up an issues related ONLY to old compilers. */ #warning "libmdbx required CLANG >= 3.8" #endif #if defined(__GLIBC__) && !__GLIBC_PREREQ(2, 12) /* Actually libmdbx was not tested with something older than glibc 2.12. * But you could ignore this warning at your own risk. * In such case please don't rise up an issues related ONLY to old systems. */ #warning "libmdbx was only tested with GLIBC >= 2.12." #endif #ifdef __SANITIZE_THREAD__ #warning \ "libmdbx don't compatible with ThreadSanitizer, you will get a lot of false-positive issues." #endif /* __SANITIZE_THREAD__ */ #if __has_warning("-Wnested-anon-types") #if defined(__clang__) #pragma clang diagnostic ignored "-Wnested-anon-types" #elif defined(__GNUC__) #pragma GCC diagnostic ignored "-Wnested-anon-types" #else #pragma warning disable "nested-anon-types" #endif #endif /* -Wnested-anon-types */ #if __has_warning("-Wconstant-logical-operand") #if defined(__clang__) #pragma clang diagnostic ignored "-Wconstant-logical-operand" #elif defined(__GNUC__) #pragma GCC diagnostic ignored "-Wconstant-logical-operand" #else #pragma warning disable "constant-logical-operand" #endif #endif /* -Wconstant-logical-operand */ #if defined(__LCC__) && (__LCC__ <= 121) /* bug #2798 */ #pragma diag_suppress alignment_reduction_ignored #elif defined(__ICC) #pragma warning(disable : 3453 1366) #elif __has_warning("-Walignment-reduction-ignored") #if defined(__clang__) #pragma clang diagnostic ignored "-Walignment-reduction-ignored" #elif defined(__GNUC__) #pragma GCC diagnostic ignored "-Walignment-reduction-ignored" #else #pragma warning disable "alignment-reduction-ignored" #endif #endif /* -Walignment-reduction-ignored */ #ifdef __cplusplus extern "C" { #endif #include "osal.h" #define mdbx_sourcery_anchor XCONCAT(mdbx_sourcery_, MDBX_BUILD_SOURCERY) #if defined(xMDBX_TOOLS) extern LIBMDBX_API const char *const mdbx_sourcery_anchor; #endif #include "options.h" /* Undefine the NDEBUG if debugging is enforced by MDBX_DEBUG */ #if MDBX_DEBUG #undef NDEBUG #endif /*----------------------------------------------------------------------------*/ /* Atomics */ enum MDBX_memory_order { mo_Relaxed, mo_AcquireRelease, mo_SequentialConsistency }; typedef union { volatile uint32_t weak; #ifdef MDBX_HAVE_C11ATOMICS volatile _Atomic uint32_t c11a; #endif /* MDBX_HAVE_C11ATOMICS */ } MDBX_atomic_uint32_t; typedef union { volatile uint64_t weak; #if defined(MDBX_HAVE_C11ATOMICS) && (MDBX_64BIT_CAS || MDBX_64BIT_ATOMIC) volatile _Atomic uint64_t c11a; #endif #if !defined(MDBX_HAVE_C11ATOMICS) || !MDBX_64BIT_CAS || !MDBX_64BIT_ATOMIC __anonymous_struct_extension__ struct { #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ MDBX_atomic_uint32_t low, high; #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ MDBX_atomic_uint32_t high, low; #else #error "FIXME: Unsupported byte order" #endif /* __BYTE_ORDER__ */ }; #endif } MDBX_atomic_uint64_t; #ifdef MDBX_HAVE_C11ATOMICS /* Crutches for C11 atomic compiler's bugs */ #if defined(__e2k__) && defined(__LCC__) && __LCC__ < /* FIXME */ 127 #define MDBX_c11a_ro(type, ptr) (&(ptr)->weak) #define MDBX_c11a_rw(type, ptr) (&(ptr)->weak) #elif defined(__clang__) && __clang__ < 8 #define MDBX_c11a_ro(type, ptr) ((volatile _Atomic(type) *)&(ptr)->c11a) #define MDBX_c11a_rw(type, ptr) (&(ptr)->c11a) #else #define MDBX_c11a_ro(type, ptr) (&(ptr)->c11a) #define MDBX_c11a_rw(type, ptr) (&(ptr)->c11a) #endif /* Crutches for C11 atomic compiler's bugs */ static __always_inline memory_order mo_c11_store(enum MDBX_memory_order fence) { switch (fence) { default: assert(false); __unreachable(); case mo_Relaxed: return memory_order_relaxed; case mo_AcquireRelease: return memory_order_release; case mo_SequentialConsistency: return memory_order_seq_cst; } } static __always_inline memory_order mo_c11_load(enum MDBX_memory_order fence) { switch (fence) { default: assert(false); __unreachable(); case mo_Relaxed: return memory_order_relaxed; case mo_AcquireRelease: return memory_order_acquire; case mo_SequentialConsistency: return memory_order_seq_cst; } } #endif /* MDBX_HAVE_C11ATOMICS */ #ifndef __cplusplus MDBX_MAYBE_UNUSED static __always_inline void mdbx_memory_fence(enum MDBX_memory_order order, bool write) { #ifdef MDBX_HAVE_C11ATOMICS atomic_thread_fence(write ? mo_c11_store(order) : mo_c11_load(order)); #else /* MDBX_HAVE_C11ATOMICS */ mdbx_compiler_barrier(); if (write && order > (MDBX_CPU_WRITEBACK_INCOHERENT ? mo_Relaxed : mo_AcquireRelease)) mdbx_memory_barrier(); #endif /* MDBX_HAVE_C11ATOMICS */ } MDBX_MAYBE_UNUSED static __always_inline uint32_t atomic_store32(MDBX_atomic_uint32_t *p, const uint32_t value, enum MDBX_memory_order order) { STATIC_ASSERT(sizeof(MDBX_atomic_uint32_t) == 4); #ifdef MDBX_HAVE_C11ATOMICS assert(atomic_is_lock_free(MDBX_c11a_rw(uint32_t, p))); atomic_store_explicit(MDBX_c11a_rw(uint32_t, p), value, mo_c11_store(order)); #else /* MDBX_HAVE_C11ATOMICS */ if (order != mo_Relaxed) mdbx_compiler_barrier(); p->weak = value; mdbx_memory_fence(order, true); #endif /* MDBX_HAVE_C11ATOMICS */ return value; } MDBX_MAYBE_UNUSED static __always_inline uint32_t atomic_load32(const MDBX_atomic_uint32_t *p, enum MDBX_memory_order order) { STATIC_ASSERT(sizeof(MDBX_atomic_uint32_t) == 4); #ifdef MDBX_HAVE_C11ATOMICS assert(atomic_is_lock_free(MDBX_c11a_ro(uint32_t, p))); return atomic_load_explicit(MDBX_c11a_ro(uint32_t, p), mo_c11_load(order)); #else /* MDBX_HAVE_C11ATOMICS */ mdbx_memory_fence(order, false); const uint32_t value = p->weak; if (order != mo_Relaxed) mdbx_compiler_barrier(); return value; #endif /* MDBX_HAVE_C11ATOMICS */ } #endif /* !__cplusplus */ /*----------------------------------------------------------------------------*/ /* Basic constants and types */ /* A stamp that identifies a file as an MDBX file. * There's nothing special about this value other than that it is easily * recognizable, and it will reflect any byte order mismatches. */ #define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11) /* FROZEN: The version number for a database's datafile format. */ #define MDBX_DATA_VERSION 3 /* The version number for a database's lockfile format. */ #define MDBX_LOCK_VERSION 4 /* 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 3 /* A page number in the database. * * MDBX uses 32 bit for page numbers. This limits database * size up to 2^44 bytes, in case of 4K pages. */ typedef uint32_t pgno_t; typedef MDBX_atomic_uint32_t atomic_pgno_t; #define PRIaPGNO PRIu32 #define MAX_PAGENO UINT32_C(0x7FFFffff) #define MIN_PAGENO NUM_METAS #define SAFE64_INVALID_THRESHOLD UINT64_C(0xffffFFFF00000000) /* A transaction ID. */ typedef uint64_t txnid_t; typedef MDBX_atomic_uint64_t atomic_txnid_t; #define PRIaTXN PRIi64 #define MIN_TXNID UINT64_C(1) #define MAX_TXNID (SAFE64_INVALID_THRESHOLD - 1) #define INITIAL_TXNID (MIN_TXNID + NUM_METAS - 1) #define INVALID_TXNID UINT64_MAX /* LY: for testing non-atomic 64-bit txnid on 32-bit arches. * #define xMDBX_TXNID_STEP (UINT32_MAX / 3) */ #ifndef xMDBX_TXNID_STEP #if MDBX_64BIT_CAS #define xMDBX_TXNID_STEP 1u #else #define xMDBX_TXNID_STEP 2u #endif #endif /* xMDBX_TXNID_STEP */ /* 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; #define MEGABYTE ((size_t)1 << 20) /*----------------------------------------------------------------------------*/ /* Core structures for database and shared memory (i.e. format definition) */ #pragma pack(push, 4) /* Information about a single database in the environment. */ typedef struct MDBX_db { uint16_t md_flags; /* see mdbx_dbi_open */ uint16_t md_depth; /* depth of this tree */ uint32_t md_xsize; /* key-size for MDBX_DUPFIXED (LEAF2 pages) */ pgno_t md_root; /* the root page 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 */ uint64_t md_seq; /* table sequence counter */ uint64_t md_entries; /* number of data items */ uint64_t md_mod_txnid; /* txnid of last committed modification */ } MDBX_db; /* database size-related parameters */ typedef struct MDBX_geo { uint16_t grow_pv; /* datafile growth step as a 16-bit packed (exponential quantized) value */ uint16_t shrink_pv; /* datafile shrink threshold as a 16-bit packed (exponential quantized) value */ pgno_t lower; /* minimal size of datafile in pages */ pgno_t upper; /* maximal size of datafile in pages */ pgno_t now; /* current size of datafile in pages */ pgno_t next; /* first unused page in the datafile, but actually the file may be shorter. */ } MDBX_geo; /* 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 MDBX_meta { /* Stamp identifying this as an MDBX file. * It must be set to MDBX_MAGIC with MDBX_DATA_VERSION. */ uint32_t mm_magic_and_version[2]; /* txnid that committed this page, the first of a two-phase-update pair */ uint32_t mm_txnid_a[2]; uint16_t mm_extra_flags; /* extra DB flags, zero (nothing) for now */ uint8_t mm_validator_id; /* ID of checksum and page validation method, * zero (nothing) for now */ uint8_t mm_extra_pagehdr; /* extra bytes in the page header, * zero (nothing) for now */ MDBX_geo mm_geo; /* database size-related parameters */ MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */ /* The size of pages used in this DB */ #define mm_psize mm_dbs[FREE_DBI].md_xsize MDBX_canary mm_canary; #define MDBX_DATASIGN_NONE 0u #define MDBX_DATASIGN_WEAK 1u #define SIGN_IS_STEADY(sign) ((sign) > MDBX_DATASIGN_WEAK) #define META_IS_STEADY(meta) \ SIGN_IS_STEADY(unaligned_peek_u64_volatile(4, (meta)->mm_datasync_sign)) uint32_t mm_datasync_sign[2]; /* txnid that committed this page, the second of a two-phase-update pair */ uint32_t mm_txnid_b[2]; /* Number of non-meta pages which were put in GC after COW. May be 0 in case * DB was previously handled by libmdbx without corresponding feature. * This value in couple with mr_snapshot_pages_retired allows fast estimation * of "how much reader is restraining GC recycling". */ uint32_t mm_pages_retired[2]; /* The analogue /proc/sys/kernel/random/boot_id or similar to determine * whether the system was rebooted after the last use of the database files. * If there was no reboot, but there is no need to rollback to the last * steady sync point. Zeros mean that no relevant information is available * from the system. */ bin128_t mm_bootid; } MDBX_meta; #pragma pack(1) /* Common header for all page types. The page type depends on mp_flags. * * P_BRANCH and P_LEAF pages have unsorted 'MDBX_node's at the end, with * sorted mp_ptrs[] entries referring to them. Exception: P_LEAF2 pages * omit mp_ptrs and pack sorted MDBX_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 MDBX_meta, the start point of an MDBX snapshot. * * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once * in the snapshot: Either used by a database or listed in a GC record. */ typedef struct MDBX_page { union { #define IS_FROZEN(txn, p) ((p)->mp_txnid < (txn)->mt_txnid) #define IS_SPILLED(txn, p) ((p)->mp_txnid == (txn)->mt_txnid) #define IS_SHADOWED(txn, p) ((p)->mp_txnid > (txn)->mt_txnid) #define IS_VALID(txn, p) ((p)->mp_txnid <= (txn)->mt_front) #define IS_MODIFIABLE(txn, p) ((p)->mp_txnid == (txn)->mt_front) uint64_t mp_txnid; struct MDBX_page *mp_next; /* for in-memory list of freed pages */ }; uint16_t mp_leaf2_ksize; /* key size if this is a LEAF2 page */ #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_BAD 0x10 /* explicit flag for invalid/bad page */ #define P_LEAF2 0x20 /* for MDBX_DUPFIXED records */ #define P_SUBP 0x40 /* for MDBX_DUPSORT sub-pages */ #define P_SPILLED 0x2000 /* spilled in parent txn */ #define P_LOOSE 0x4000 /* page was dirtied then freed, can be reused */ #define P_FROZEN 0x8000 /* used for retire page with known status */ #define P_ILL_BITS (~(P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW | P_SPILLED)) uint16_t mp_flags; union { uint32_t mp_pages; /* number of overflow pages */ __anonymous_struct_extension__ struct { indx_t mp_lower; /* lower bound of free space */ indx_t mp_upper; /* upper bound of free space */ }; }; pgno_t mp_pgno; /* page number */ #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \ (!defined(__cplusplus) && defined(_MSC_VER)) indx_t mp_ptrs[] /* dynamic size */; #endif /* C99 */ } MDBX_page; /* Size of the page header, excluding dynamic data at the end */ #define PAGEHDRSZ ((unsigned)offsetof(MDBX_page, mp_ptrs)) #pragma pack(pop) #if MDBX_ENABLE_PGOP_STAT /* Statistics of page operations overall of all (running, completed and aborted) * transactions */ typedef struct { MDBX_atomic_uint64_t newly; /* Quantity of a new pages added */ MDBX_atomic_uint64_t cow; /* Quantity of pages copied for update */ MDBX_atomic_uint64_t clone; /* Quantity of parent's dirty pages clones for nested transactions */ MDBX_atomic_uint64_t split; /* Page splits */ MDBX_atomic_uint64_t merge; /* Page merges */ MDBX_atomic_uint64_t spill; /* Quantity of spilled dirty pages */ MDBX_atomic_uint64_t unspill; /* Quantity of unspilled/reloaded pages */ MDBX_atomic_uint64_t wops; /* Number of explicit write operations (not a pages) to a disk */ } MDBX_pgop_stat_t; #endif /* MDBX_ENABLE_PGOP_STAT */ #if MDBX_LOCKING == MDBX_LOCKING_WIN32FILES #define MDBX_CLOCK_SIGN UINT32_C(0xF10C) typedef void mdbx_ipclock_t; #elif MDBX_LOCKING == MDBX_LOCKING_SYSV #define MDBX_CLOCK_SIGN UINT32_C(0xF18D) typedef mdbx_pid_t mdbx_ipclock_t; #ifndef EOWNERDEAD #define EOWNERDEAD MDBX_RESULT_TRUE #endif #elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 || \ MDBX_LOCKING == MDBX_LOCKING_POSIX2008 #define MDBX_CLOCK_SIGN UINT32_C(0x8017) typedef pthread_mutex_t mdbx_ipclock_t; #elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988 #define MDBX_CLOCK_SIGN UINT32_C(0xFC29) typedef sem_t mdbx_ipclock_t; #else #error "FIXME" #endif /* MDBX_LOCKING */ #if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus) MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc); MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc); #endif /* MDBX_LOCKING */ /* Reader Lock Table * * Readers don't acquire any locks for their data access. Instead, they * simply record their transaction ID in the reader table. The reader * mutex is needed just to find an empty slot in the reader table. The * slot's address is saved in thread-specific data so that subsequent * read transactions started by the same thread need no further locking to * proceed. * * If MDBX_NOTLS is set, the slot address is not saved in thread-specific data. * No reader table is used if the database is on a read-only filesystem. * * Since the database uses multi-version concurrency control, readers don't * actually need any locking. This table is used to keep track of which * readers are using data from which old transactions, so that we'll know * when a particular old transaction is no longer in use. Old transactions * that have discarded any data pages can then have those pages reclaimed * for use by a later write transaction. * * The lock table is constructed such that reader slots are aligned with the * processor's cache line size. Any slot is only ever used by one thread. * This alignment guarantees that there will be no contention or cache * thrashing as threads update their own slot info, and also eliminates * any need for locking when accessing a slot. * * A writer thread will scan every slot in the table to determine the oldest * outstanding reader transaction. Any freed pages older than this will be * reclaimed by the writer. The writer doesn't use any locks when scanning * this table. This means that there's no guarantee that the writer will * see the most up-to-date reader info, but that's not required for correct * operation - all we need is to know the upper bound on the oldest reader, * we don't care at all about the newest reader. So the only consequence of * reading stale information here is that old pages might hang around a * while longer before being reclaimed. That's actually good anyway, because * the longer we delay reclaiming old pages, the more likely it is that a * string of contiguous pages can be found after coalescing old pages from * many old transactions together. */ /* The actual reader record, with cacheline padding. */ typedef struct MDBX_reader { /* 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. */ MDBX_atomic_uint64_t /* txnid_t */ mr_txnid; /* 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. */ /* The thread ID of the thread owning this txn. */ MDBX_atomic_uint64_t mr_tid; /* The process ID of the process owning this reader txn. */ MDBX_atomic_uint32_t mr_pid; /* The number of pages used in the reader's MVCC snapshot, * i.e. the value of meta->mm_geo.next and txn->mt_next_pgno */ atomic_pgno_t mr_snapshot_pages_used; /* Number of retired pages at the time this reader starts transaction. So, * at any time the difference mm_pages_retired - mr_snapshot_pages_retired * will give the number of pages which this reader restraining from reuse. */ MDBX_atomic_uint64_t mr_snapshot_pages_retired; } MDBX_reader; /* The header for the reader table (a memory-mapped lock file). */ typedef struct MDBX_lockinfo { /* Stamp identifying this as an MDBX file. * It must be set to MDBX_MAGIC with with MDBX_LOCK_VERSION. */ uint64_t mti_magic_and_version; /* Format of this lock file. Must be set to MDBX_LOCK_FORMAT. */ uint32_t mti_os_and_format; /* Flags which environment was opened. */ MDBX_atomic_uint32_t mti_envmode; /* Threshold of un-synced-with-disk pages for auto-sync feature, * zero means no-threshold, i.e. auto-sync is disabled. */ atomic_pgno_t mti_autosync_threshold; /* Low 32-bit of txnid with which meta-pages was synced, * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */ MDBX_atomic_uint32_t mti_meta_sync_txnid; /* Period for timed auto-sync feature, i.e. at the every steady checkpoint * the mti_unsynced_timeout sets to the current_time + mti_autosync_period. * The time value is represented in a suitable system-dependent form, for * example clock_gettime(CLOCK_BOOTTIME) or clock_gettime(CLOCK_MONOTONIC). * Zero means timed auto-sync is disabled. */ MDBX_atomic_uint64_t mti_autosync_period; /* Marker to distinguish uniqueness of DB/CLK. */ MDBX_atomic_uint64_t mti_bait_uniqueness; MDBX_ALIGNAS(MDBX_CACHELINE_SIZE) /* cacheline ----------------------------*/ #if MDBX_ENABLE_PGOP_STAT /* Statistics of costly ops of all (running, completed and aborted) * transactions */ MDBX_pgop_stat_t mti_pgop_stat; #endif /* MDBX_ENABLE_PGOP_STAT*/ MDBX_ALIGNAS(MDBX_CACHELINE_SIZE) /* cacheline ----------------------------*/ /* Write transaction lock. */ #if MDBX_LOCKING > 0 mdbx_ipclock_t mti_wlock; #endif /* MDBX_LOCKING > 0 */ atomic_txnid_t mti_oldest_reader; /* Timestamp of the last steady sync. Value is represented in a suitable * system-dependent form, for example clock_gettime(CLOCK_BOOTTIME) or * clock_gettime(CLOCK_MONOTONIC). */ MDBX_atomic_uint64_t mti_sync_timestamp; /* Number un-synced-with-disk pages for auto-sync feature. */ atomic_pgno_t mti_unsynced_pages; /* Number of page which was discarded last time by madvise(MADV_FREE). */ atomic_pgno_t mti_discarded_tail; /* Timestamp of the last readers check. */ MDBX_atomic_uint64_t mti_reader_check_timestamp; /* Shared anchor for tracking readahead edge and enabled/disabled status. */ pgno_t mti_readahead_anchor; MDBX_ALIGNAS(MDBX_CACHELINE_SIZE) /* cacheline ----------------------------*/ /* Readeaders registration lock. */ #if MDBX_LOCKING > 0 mdbx_ipclock_t mti_rlock; #endif /* MDBX_LOCKING > 0 */ /* 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. */ MDBX_atomic_uint32_t mti_numreaders; MDBX_atomic_uint32_t mti_readers_refresh_flag; #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \ (!defined(__cplusplus) && defined(_MSC_VER)) MDBX_ALIGNAS(MDBX_CACHELINE_SIZE) /* cacheline ----------------------------*/ MDBX_reader mti_readers[] /* dynamic size */; #endif /* C99 */ } MDBX_lockinfo; /* Lockfile format signature: version, features and field layout */ #define MDBX_LOCK_FORMAT \ (MDBX_CLOCK_SIGN * 27733 + (unsigned)sizeof(MDBX_reader) * 13 + \ (unsigned)offsetof(MDBX_reader, mr_snapshot_pages_used) * 251 + \ (unsigned)offsetof(MDBX_lockinfo, mti_oldest_reader) * 83 + \ (unsigned)offsetof(MDBX_lockinfo, mti_numreaders) * 37 + \ (unsigned)offsetof(MDBX_lockinfo, mti_readers) * 29) #define MDBX_DATA_MAGIC \ ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION) #define MDBX_DATA_MAGIC_LEGACY_COMPAT \ ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + 2) #define MDBX_DATA_MAGIC_LEGACY_DEVEL ((MDBX_MAGIC << 8) + 255) #define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION) /* The maximum size of a database page. * * It is 64K, but value-PAGEHDRSZ must fit in MDBX_page.mp_upper. * * MDBX will use database pages < OS pages if needed. * That causes more I/O in write transactions: The OS must * know (read) the whole page before writing a partial page. * * Note that we don't currently support Huge pages. On Linux, * regular data files cannot use Huge pages, and in general * Huge pages aren't actually pageable. We rely on the OS * demand-pager to read our data and page it out when memory * pressure from other processes is high. So until OSs have * actual paging support for Huge pages, they're not viable. */ #define MAX_PAGESIZE MDBX_MAX_PAGESIZE #define MIN_PAGESIZE MDBX_MIN_PAGESIZE #define MIN_MAPSIZE (MIN_PAGESIZE * MIN_PAGENO) #if defined(_WIN32) || defined(_WIN64) #define MAX_MAPSIZE32 UINT32_C(0x38000000) #else #define MAX_MAPSIZE32 UINT32_C(0x7f000000) #endif #define MAX_MAPSIZE64 ((MAX_PAGENO + 1) * (uint64_t)MAX_PAGESIZE) #if MDBX_WORDBITS >= 64 #define MAX_MAPSIZE MAX_MAPSIZE64 #define MDBX_PGL_LIMIT ((size_t)MAX_PAGENO) #else #define MAX_MAPSIZE MAX_MAPSIZE32 #define MDBX_PGL_LIMIT (MAX_MAPSIZE32 / MIN_PAGESIZE) #endif /* MDBX_WORDBITS */ #define MDBX_READERS_LIMIT 32767 #define MDBX_RADIXSORT_THRESHOLD 333 /*----------------------------------------------------------------------------*/ /* An PNL is an Page Number List, a sorted array of IDs. * The first element of the array is a counter for how many actual page-numbers * are in the list. By default PNLs are sorted in descending order, this allow * cut off a page with lowest pgno (at the tail) just truncating the list. The * sort order of PNLs is controlled by the MDBX_PNL_ASCENDING build option. */ typedef pgno_t *MDBX_PNL; #if MDBX_PNL_ASCENDING #define MDBX_PNL_ORDERED(first, last) ((first) < (last)) #define MDBX_PNL_DISORDERED(first, last) ((first) >= (last)) #else #define MDBX_PNL_ORDERED(first, last) ((first) > (last)) #define MDBX_PNL_DISORDERED(first, last) ((first) <= (last)) #endif /* List of txnid, only for MDBX_txn.tw.lifo_reclaimed */ typedef txnid_t *MDBX_TXL; /* An Dirty-Page list item is an pgno/pointer pair. */ typedef struct MDBX_dp { MDBX_page *ptr; pgno_t pgno; union { unsigned extra; __anonymous_struct_extension__ struct { unsigned multi : 1; unsigned lru : 31; }; }; } MDBX_dp; /* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */ typedef struct MDBX_dpl { unsigned sorted; unsigned length; unsigned detent; /* allocated size excluding the MDBX_DPL_RESERVE_GAP */ #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \ (!defined(__cplusplus) && defined(_MSC_VER)) MDBX_dp items[] /* dynamic size with holes at zero and after the last */; #endif } MDBX_dpl; /* PNL sizes */ #define MDBX_PNL_GRANULATE 1024 #define MDBX_PNL_INITIAL \ (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t)) #define MDBX_TXL_GRANULATE 32 #define MDBX_TXL_INITIAL \ (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t)) #define MDBX_TXL_MAX \ ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t)) #define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1]) #define MDBX_PNL_SIZE(pl) ((pl)[0]) #define MDBX_PNL_FIRST(pl) ((pl)[1]) #define MDBX_PNL_LAST(pl) ((pl)[MDBX_PNL_SIZE(pl)]) #define MDBX_PNL_BEGIN(pl) (&(pl)[1]) #define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_SIZE(pl) + 1]) #if MDBX_PNL_ASCENDING #define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl) #define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl) #else #define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl) #define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl) #endif #define MDBX_PNL_SIZEOF(pl) ((MDBX_PNL_SIZE(pl) + 1) * sizeof(pgno_t)) #define MDBX_PNL_IS_EMPTY(pl) (MDBX_PNL_SIZE(pl) == 0) /*----------------------------------------------------------------------------*/ /* Internal structures */ /* 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 MDBX_dbx { MDBX_val md_name; /* name of the database */ MDBX_cmp_func *md_cmp; /* function for comparing keys */ MDBX_cmp_func *md_dcmp; /* function for comparing data items */ size_t md_klen_min, md_klen_max; /* min/max key length for the database */ size_t md_vlen_min, md_vlen_max; /* min/max value/data length for the database */ } MDBX_dbx; /* A database transaction. * Every operation requires a transaction handle. */ struct MDBX_txn { #define MDBX_MT_SIGNATURE UINT32_C(0x93D53A31) uint32_t mt_signature; /* Transaction Flags */ /* mdbx_txn_begin() flags */ #define MDBX_TXN_RO_BEGIN_FLAGS (MDBX_TXN_RDONLY | MDBX_TXN_RDONLY_PREPARE) #define MDBX_TXN_RW_BEGIN_FLAGS \ (MDBX_TXN_NOMETASYNC | MDBX_TXN_NOSYNC | MDBX_TXN_TRY) /* Additional flag for mdbx_sync_locked() */ #define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000) /* internal txn flags */ #define MDBX_TXN_FINISHED 0x01 /* txn is finished or never began */ #define MDBX_TXN_ERROR 0x02 /* txn is unusable after an error */ #define MDBX_TXN_DIRTY 0x04 /* must write, even if dirty list is empty */ #define MDBX_TXN_SPILLS 0x08 /* txn or a parent has spilled pages */ #define MDBX_TXN_HAS_CHILD 0x10 /* txn has an MDBX_txn.mt_child */ /* most operations on the txn are currently illegal */ #define MDBX_TXN_BLOCKED \ (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_HAS_CHILD) #define TXN_FLAGS \ (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS | \ MDBX_TXN_HAS_CHILD) #if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) || \ ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) & \ MDBX_SHRINK_ALLOWED) #error "Oops, some flags overlapped or wrong" #endif uint32_t mt_flags; MDBX_txn *mt_parent; /* parent of a nested txn */ /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */ MDBX_txn *mt_child; MDBX_geo mt_geo; /* next unallocated page */ #define mt_next_pgno mt_geo.next /* corresponding to the current size of datafile */ #define mt_end_pgno mt_geo.now /* 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; txnid_t mt_front; MDBX_env *mt_env; /* the DB environment */ /* Array of records for each DB known in the environment. */ MDBX_dbx *mt_dbxs; /* Array of MDBX_db records for each known DB */ MDBX_db *mt_dbs; /* Array of sequence numbers for each DB handle */ unsigned *mt_dbiseqs; /* Transaction DBI Flags */ #define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */ #define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */ #define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */ #define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */ #define DBI_VALID 0x10 /* DB handle is valid, see also DB_VALID */ #define DBI_USRVALID 0x20 /* As DB_VALID, but not set for FREE_DBI */ #define DBI_AUDITED 0x40 /* Internal flag for accounting during audit */ /* Array of flags for each DB */ uint8_t *mt_dbistate; /* 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. */ MDBX_dbi mt_numdbs; size_t mt_owner; /* thread ID that owns this transaction */ MDBX_canary mt_canary; void *mt_userctx; /* User-settable context */ MDBX_cursor **mt_cursors; union { struct { /* For read txns: This thread/txn's reader table slot, or NULL. */ MDBX_reader *reader; } to; struct { /* In write txns, array of cursors for each DB */ pgno_t *reclaimed_pglist; /* Reclaimed GC pages */ txnid_t last_reclaimed; /* ID of last used record */ #if MDBX_ENABLE_REFUND pgno_t loose_refund_wl /* FIXME: describe */; #endif /* MDBX_ENABLE_REFUND */ /* dirtylist room: Dirty 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 * dirtylist into mt_parent after freeing hidden mt_parent pages. */ unsigned dirtyroom; /* a sequence to spilling dirty page with LRU policy */ unsigned dirtylru; /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */ MDBX_dpl *dirtylist; /* The list of reclaimed txns from GC */ MDBX_TXL lifo_reclaimed; /* The list of pages that became unused during this transaction. */ MDBX_PNL retired_pages; /* The list of loose pages that became unused and may be reused * in this transaction, linked through `mp_next`. */ MDBX_page *loose_pages; /* Number of loose pages (tw.loose_pages) */ unsigned 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. */ MDBX_PNL spill_pages; unsigned spill_least_removed; } tw; }; }; #if MDBX_WORDBITS >= 64 #define CURSOR_STACK 32 #else #define CURSOR_STACK 24 #endif struct MDBX_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. MDBX_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 MDBX_cursor { #define MDBX_MC_LIVE UINT32_C(0xFE05D5B1) #define MDBX_MC_READY4CLOSE UINT32_C(0x2817A047) #define MDBX_MC_WAIT4EOT UINT32_C(0x90E297A7) uint32_t mc_signature; /* The database handle this cursor operates on */ MDBX_dbi mc_dbi; /* Next cursor on this DB in this txn */ MDBX_cursor *mc_next; /* Backup of the original cursor if this cursor is a shadow */ MDBX_cursor *mc_backup; /* Context used for databases with MDBX_DUPSORT, otherwise NULL */ struct MDBX_xcursor *mc_xcursor; /* The transaction that owns this cursor */ MDBX_txn *mc_txn; /* The database record for this cursor */ MDBX_db *mc_db; /* The database auxiliary record for this cursor */ MDBX_dbx *mc_dbx; /* The mt_dbistate for this database */ uint8_t *mc_dbistate; unsigned mc_snum; /* number of pushed pages */ unsigned mc_top; /* index of top page, normally mc_snum-1 */ /* 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 0x10 /* Un-track cursor when closing */ #define C_RECLAIMING 0x20 /* GC lookup is prohibited */ #define C_GCFREEZE 0x40 /* reclaimed_pglist must not be updated */ /* Cursor checking flags. */ #define C_COPYING 0x100 /* skip key-value length check (copying simplify) */ #define C_UPDATING 0x200 /* update/rebalance pending */ #define C_RETIRING 0x400 /* refs to child pages may be invalid */ #define C_SKIPORD 0x800 /* don't check keys ordering */ unsigned mc_flags; /* see mdbx_cursor */ MDBX_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 MDBX_xcursor { /* A sub-cursor for traversing the Dup DB */ MDBX_cursor mx_cursor; /* The database record for this Dup DB */ MDBX_db mx_db; /* The auxiliary DB record for this Dup DB */ MDBX_dbx mx_dbx; } MDBX_xcursor; typedef struct MDBX_cursor_couple { MDBX_cursor outer; void *mc_userctx; /* User-settable context */ MDBX_xcursor inner; } MDBX_cursor_couple; /* The database environment. */ struct MDBX_env { /* ----------------------------------------------------- mostly static part */ #define MDBX_ME_SIGNATURE UINT32_C(0x9A899641) MDBX_atomic_uint32_t me_signature; /* Failed to update the meta page. Probably an I/O error. */ #define MDBX_FATAL_ERROR UINT32_C(0x80000000) /* Some fields are initialized. */ #define MDBX_ENV_ACTIVE UINT32_C(0x20000000) /* me_txkey is set */ #define MDBX_ENV_TXKEY UINT32_C(0x10000000) /* Legacy MDBX_MAPASYNC (prior v0.9) */ #define MDBX_DEPRECATED_MAPASYNC UINT32_C(0x100000) #define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY) uint32_t me_flags; mdbx_mmap_t me_dxb_mmap; /* The main data file */ #define me_map me_dxb_mmap.dxb #define me_lazy_fd me_dxb_mmap.fd mdbx_filehandle_t me_dsync_fd; mdbx_mmap_t me_lck_mmap; /* The lock file */ #define me_lfd me_lck_mmap.fd struct MDBX_lockinfo *me_lck; unsigned me_psize; /* DB page size, initialized from me_os_psize */ unsigned me_leaf_nodemax; /* max size of a leaf-node */ uint8_t me_psize2log; /* log2 of DB page size */ int8_t me_stuck_meta; /* recovery-only: target meta page or less that zero */ uint16_t me_merge_threshold, me_merge_threshold_gc; /* pages emptier than this are candidates for merging */ unsigned me_os_psize; /* OS page size, from mdbx_syspagesize() */ unsigned me_maxreaders; /* size of the reader table */ MDBX_dbi me_maxdbs; /* size of the DB table */ uint32_t me_pid; /* process ID of this env */ mdbx_thread_key_t me_txkey; /* thread-key for readers */ char *me_pathname; /* path to the DB files */ void *me_pbuf; /* scratch area for DUPSORT put() */ MDBX_txn *me_txn0; /* preallocated write transaction */ MDBX_dbx *me_dbxs; /* array of static DB info */ uint16_t *me_dbflags; /* array of flags from MDBX_db.md_flags */ unsigned *me_dbiseqs; /* array of dbi sequence numbers */ unsigned me_maxgc_ov1page; /* Number of pgno_t fit in a single overflow page */ uint32_t me_live_reader; /* have liveness lock in reader table */ void *me_userctx; /* User-settable context */ MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */ struct { unsigned dp_reserve_limit; unsigned rp_augment_limit; unsigned dp_limit; unsigned dp_initial; uint8_t dp_loose_limit; uint8_t spill_max_denominator; uint8_t spill_min_denominator; uint8_t spill_parent4child_denominator; unsigned merge_threshold_16dot16_percent; union { unsigned all; /* tracks options with non-auto values but tuned by user */ struct { unsigned dp_limit : 1; } non_auto; } flags; } me_options; /* struct me_dbgeo used for accepting db-geo params from user for the new * database creation, i.e. when mdbx_env_set_geometry() was called before * mdbx_env_open(). */ struct { size_t lower; /* minimal size of datafile */ size_t upper; /* maximal size of datafile */ size_t now; /* current size of datafile */ size_t grow; /* step to grow datafile */ size_t shrink; /* threshold to shrink datafile */ } me_dbgeo; #if MDBX_LOCKING == MDBX_LOCKING_SYSV union { key_t key; int semid; } me_sysv_ipc; #endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */ MDBX_env *me_lcklist_next; /* --------------------------------------------------- mostly volatile part */ MDBX_txn *me_txn; /* current write transaction */ mdbx_fastmutex_t me_dbi_lock; MDBX_dbi me_numdbs; /* number of DBs opened */ MDBX_page *me_dp_reserve; /* list of malloc'ed blocks for re-use */ unsigned me_dp_reserve_len; /* PNL of pages that became unused in a write txn */ MDBX_PNL me_retired_pages; #if defined(_WIN32) || defined(_WIN64) MDBX_srwlock me_remap_guard; /* Workaround for LockFileEx and WriteFile multithread bug */ CRITICAL_SECTION me_windowsbug_lock; #else mdbx_fastmutex_t me_remap_guard; #endif /* -------------------------------------------------------------- debugging */ #if MDBX_DEBUG MDBX_assert_func *me_assert_func; /* Callback for assertion failures */ #endif #ifdef MDBX_USE_VALGRIND int me_valgrind_handle; #endif #if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__) pgno_t me_poison_edge; #endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */ #ifndef xMDBX_DEBUG_SPILLING #define xMDBX_DEBUG_SPILLING 0 #endif #if xMDBX_DEBUG_SPILLING == 2 unsigned debug_dirtied_est, debug_dirtied_act; #endif /* xMDBX_DEBUG_SPILLING */ /* ------------------------------------------------- stub for lck-less mode */ MDBX_atomic_uint64_t x_lckless_stub[(sizeof(MDBX_lockinfo) + MDBX_CACHELINE_SIZE - 1) / sizeof(MDBX_atomic_uint64_t)]; }; #ifndef __cplusplus /*----------------------------------------------------------------------------*/ /* Debug and Logging stuff */ #define MDBX_RUNTIME_FLAGS_INIT \ ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT extern uint8_t mdbx_runtime_flags; extern uint8_t mdbx_loglevel; extern MDBX_debug_func *mdbx_debug_logger; MDBX_MAYBE_UNUSED static __inline void mdbx_jitter4testing(bool tiny) { #if MDBX_DEBUG if (MDBX_DBG_JITTER & mdbx_runtime_flags) mdbx_osal_jitter(tiny); #else (void)tiny; #endif } MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5) mdbx_debug_log(int level, const char *function, int line, const char *fmt, ...) MDBX_PRINTF_ARGS(4, 5); MDBX_INTERNAL_FUNC void mdbx_debug_log_va(int level, const char *function, int line, const char *fmt, va_list args); #if MDBX_DEBUG #define mdbx_log_enabled(msg) unlikely(msg <= mdbx_loglevel) #define mdbx_audit_enabled() unlikely((mdbx_runtime_flags & MDBX_DBG_AUDIT)) #else /* MDBX_DEBUG */ #define mdbx_log_enabled(msg) (msg < MDBX_LOG_VERBOSE && msg <= mdbx_loglevel) #define mdbx_audit_enabled() (0) #endif /* MDBX_DEBUG */ #if MDBX_FORCE_ASSERTIONS #define mdbx_assert_enabled() (1) #elif MDBX_DEBUG #define mdbx_assert_enabled() likely((mdbx_runtime_flags & MDBX_DBG_ASSERT)) #else #define mdbx_assert_enabled() (0) #endif /* assertions */ #if !MDBX_DEBUG && defined(__ANDROID_API__) #define mdbx_assert_fail(env, msg, func, line) \ __android_log_assert(msg, "mdbx", "%s:%u", func, line) #else void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func, int line); #endif #define mdbx_debug_extra(fmt, ...) \ do { \ if (mdbx_log_enabled(MDBX_LOG_EXTRA)) \ mdbx_debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__); \ } while (0) #define mdbx_debug_extra_print(fmt, ...) \ do { \ if (mdbx_log_enabled(MDBX_LOG_EXTRA)) \ mdbx_debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__); \ } while (0) #define mdbx_trace(fmt, ...) \ do { \ if (mdbx_log_enabled(MDBX_LOG_TRACE)) \ mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n", \ __VA_ARGS__); \ } while (0) #define mdbx_debug(fmt, ...) \ do { \ if (mdbx_log_enabled(MDBX_LOG_DEBUG)) \ mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n", \ __VA_ARGS__); \ } while (0) #define mdbx_verbose(fmt, ...) \ do { \ if (mdbx_log_enabled(MDBX_LOG_VERBOSE)) \ mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n", \ __VA_ARGS__); \ } while (0) #define mdbx_notice(fmt, ...) \ do { \ if (mdbx_log_enabled(MDBX_LOG_NOTICE)) \ mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n", \ __VA_ARGS__); \ } while (0) #define mdbx_warning(fmt, ...) \ do { \ if (mdbx_log_enabled(MDBX_LOG_WARN)) \ mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n", \ __VA_ARGS__); \ } while (0) #define mdbx_error(fmt, ...) \ do { \ if (mdbx_log_enabled(MDBX_LOG_ERROR)) \ mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n", \ __VA_ARGS__); \ } while (0) #define mdbx_fatal(fmt, ...) \ mdbx_debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__); #define mdbx_ensure_msg(env, expr, msg) \ do { \ if (unlikely(!(expr))) \ mdbx_assert_fail(env, msg, __func__, __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) #ifndef xMDBX_TOOLS /* Avoid using internal mdbx_assert() */ #undef assert #define assert(expr) mdbx_assert(NULL, expr) #endif /*----------------------------------------------------------------------------*/ /* Cache coherence and mmap invalidation */ #if MDBX_CPU_WRITEBACK_INCOHERENT #define mdbx_flush_incoherent_cpu_writeback() mdbx_memory_barrier() #else #define mdbx_flush_incoherent_cpu_writeback() mdbx_compiler_barrier() #endif /* MDBX_CPU_WRITEBACK_INCOHERENT */ MDBX_MAYBE_UNUSED static __inline void mdbx_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) { #if MDBX_MMAP_INCOHERENT_FILE_WRITE char *const begin = (char *)(-pagesize & (intptr_t)addr); char *const end = (char *)(-pagesize & (intptr_t)((char *)addr + nbytes + pagesize - 1)); int err = msync(begin, end - begin, MS_SYNC | MS_INVALIDATE) ? errno : 0; mdbx_assert(nullptr, err == 0); (void)err; #else (void)pagesize; #endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */ #if MDBX_MMAP_INCOHERENT_CPU_CACHE #ifdef DCACHE /* MIPS has cache coherency issues. * Note: for any nbytes >= on-chip cache size, entire is flushed. */ cacheflush(addr, nbytes, DCACHE); #else #error "Oops, cacheflush() not available" #endif /* DCACHE */ #endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */ #if !MDBX_MMAP_INCOHERENT_FILE_WRITE && !MDBX_MMAP_INCOHERENT_CPU_CACHE (void)addr; (void)nbytes; #endif } /*----------------------------------------------------------------------------*/ /* Internal prototypes */ MDBX_INTERNAL_FUNC int mdbx_cleanup_dead_readers(MDBX_env *env, int rlocked, int *dead); MDBX_INTERNAL_FUNC int mdbx_rthc_alloc(mdbx_thread_key_t *key, MDBX_reader *begin, MDBX_reader *end); MDBX_INTERNAL_FUNC void mdbx_rthc_remove(const mdbx_thread_key_t key); MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void); MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void); MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr); #endif /* !__cplusplus */ #define MDBX_IS_ERROR(rc) \ ((rc) != MDBX_RESULT_TRUE && (rc) != MDBX_RESULT_FALSE) /* Internal error codes, not exposed outside libmdbx */ #define MDBX_NO_ROOT (MDBX_LAST_ADDED_ERRCODE + 10) /* Debugging output value of a cursor DBI: Negative in a sub-cursor. */ #define DDBI(mc) \ (((mc)->mc_flags & C_SUB) ? -(int)(mc)->mc_dbi : (int)(mc)->mc_dbi) /* Key size which fits in a DKBUF (debug key buffer). */ #define DKBUF_MAX 511 #define DKBUF char _kbuf[DKBUF_MAX * 4 + 2] #define DKEY(x) mdbx_dump_val(x, _kbuf, DKBUF_MAX * 2 + 1) #define DVAL(x) mdbx_dump_val(x, _kbuf + DKBUF_MAX * 2 + 1, DKBUF_MAX * 2 + 1) #if MDBX_DEBUG #define DKBUF_DEBUG DKBUF #define DKEY_DEBUG(x) DKEY(x) #define DVAL_DEBUG(x) DVAL(x) #else #define DKBUF_DEBUG ((void)(0)) #define DKEY_DEBUG(x) ("-") #define DVAL_DEBUG(x) ("-") #endif /* An invalid page number. * Mainly used to denote an empty tree. */ #define P_INVALID (~(pgno_t)0) /* Test if the flags f are set in a flag word w. */ #define F_ISSET(w, f) (((w) & (f)) == (f)) /* Round n up to an even number. */ #define EVEN(n) (((n) + 1U) & -2) /* sign-extending -2 to match n+1U */ /* Default size of memory map. * This is certainly too small for any actual applications. Apps should * always set the size explicitly using mdbx_env_set_geometry(). */ #define DEFAULT_MAPSIZE MEGABYTE /* Number of slots in the reader table. * This value was chosen somewhat arbitrarily. The 61 is a prime number, * and such readers plus a couple mutexes fit into single 4KB page. * Applications should set the table size using mdbx_env_set_maxreaders(). */ #define DEFAULT_READERS 61 /* Test if a page is a leaf page */ #define IS_LEAF(p) (((p)->mp_flags & P_LEAF) != 0) /* Test if a page is a LEAF2 page */ #define IS_LEAF2(p) unlikely(((p)->mp_flags & P_LEAF2) != 0) /* Test if a page is a branch page */ #define IS_BRANCH(p) (((p)->mp_flags & P_BRANCH) != 0) /* Test if a page is an overflow page */ #define IS_OVERFLOW(p) unlikely(((p)->mp_flags & P_OVERFLOW) != 0) /* Test if a page is a sub page */ #define IS_SUBP(p) (((p)->mp_flags & P_SUBP) != 0) #define PAGETYPE(p) ((p)->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW)) /* Header for a single key/data pair within a page. * Used in pages of type P_BRANCH and P_LEAF without P_LEAF2. * We guarantee 2-byte alignment for 'MDBX_node's. * * Leaf node flags describe node contents. F_BIGDATA says the node's * data part is the page number of an overflow page with actual data. * F_DUPDATA and F_SUBDATA can be combined giving duplicate data in * a sub-page/sub-database, and named databases (just F_SUBDATA). */ typedef struct MDBX_node { #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ union { uint32_t mn_dsize; uint32_t mn_pgno32; }; uint8_t mn_flags; /* see mdbx_node flags */ uint8_t mn_extra; uint16_t mn_ksize; /* key size */ #else uint16_t mn_ksize; /* key size */ uint8_t mn_extra; uint8_t mn_flags; /* see mdbx_node flags */ union { uint32_t mn_pgno32; uint32_t mn_dsize; }; #endif /* __BYTE_ORDER__ */ /* mdbx_node Flags */ #define F_BIGDATA 0x01 /* data put on overflow page */ #define F_SUBDATA 0x02 /* data is a sub-database */ #define F_DUPDATA 0x04 /* data has duplicates */ /* valid flags for mdbx_node_add() */ #define NODE_ADD_FLAGS (F_DUPDATA | F_SUBDATA | MDBX_RESERVE | MDBX_APPEND) #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \ (!defined(__cplusplus) && defined(_MSC_VER)) uint8_t mn_data[] /* key and data are appended here */; #endif /* C99 */ } MDBX_node; #define DB_PERSISTENT_FLAGS \ (MDBX_REVERSEKEY | MDBX_DUPSORT | MDBX_INTEGERKEY | MDBX_DUPFIXED | \ MDBX_INTEGERDUP | MDBX_REVERSEDUP) /* mdbx_dbi_open() flags */ #define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE) #define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */ #define DB_INTERNAL_FLAGS DB_VALID #if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS #error "Oops, some flags overlapped or wrong" #endif #if DB_PERSISTENT_FLAGS & ~DB_USABLE_FLAGS #error "Oops, some flags overlapped or wrong" #endif /* max number of pages to commit in one writev() call */ #define MDBX_COMMIT_PAGES 64 #if defined(IOV_MAX) && IOV_MAX < MDBX_COMMIT_PAGES /* sysconf(_SC_IOV_MAX) */ #undef MDBX_COMMIT_PAGES #define MDBX_COMMIT_PAGES IOV_MAX #endif /* * / * | -1, a < b * CMP2INT(a,b) = < 0, a == b * | 1, a > b * \ */ #ifndef __e2k__ /* LY: fast enough on most systems */ #define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b)) #else /* LY: more parallelable on VLIW Elbrus */ #define CMP2INT(a, b) (((a) > (b)) - ((b) > (a))) #endif /* Do not spill pages to disk if txn is getting full, may fail instead */ #define MDBX_NOSPILL 0x8000 MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __inline pgno_t int64pgno(int64_t i64) { if (likely(i64 >= (int64_t)MIN_PAGENO && i64 <= (int64_t)MAX_PAGENO + 1)) return (pgno_t)i64; return (i64 < (int64_t)MIN_PAGENO) ? MIN_PAGENO : MAX_PAGENO; } MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __inline pgno_t pgno_add(size_t base, size_t augend) { assert(base <= MAX_PAGENO + 1 && augend < MAX_PAGENO); return int64pgno(base + augend); } MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __inline pgno_t pgno_sub(size_t base, size_t subtrahend) { assert(base >= MIN_PAGENO && base <= MAX_PAGENO + 1 && subtrahend < MAX_PAGENO); return int64pgno(base - subtrahend); } MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __always_inline bool is_powerof2(size_t x) { return (x & (x - 1)) == 0; } MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __always_inline size_t floor_powerof2(size_t value, size_t granularity) { assert(is_powerof2(granularity)); return value & ~(granularity - 1); } MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static __always_inline size_t ceil_powerof2(size_t value, size_t granularity) { return floor_powerof2(value + granularity - 1, granularity); } MDBX_MAYBE_UNUSED MDBX_NOTHROW_CONST_FUNCTION static unsigned log2n_powerof2(size_t value) { assert(value > 0 && value < INT32_MAX && is_powerof2(value)); assert((value & -(int32_t)value) == value); #if __GNUC_PREREQ(4, 1) || __has_builtin(__builtin_ctzl) return __builtin_ctzl(value); #elif defined(_MSC_VER) unsigned long index; _BitScanForward(&index, (unsigned long)value); return index; #else static const uint8_t debruijn_ctz32[32] = { 0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8, 31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9}; return debruijn_ctz32[(uint32_t)(value * 0x077CB531u) >> 27]; #endif } /* Only a subset of the mdbx_env flags can be changed * at runtime. Changing other flags requires closing the * environment and re-opening it with the new flags. */ #define ENV_CHANGEABLE_FLAGS \ (MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC | MDBX_DEPRECATED_MAPASYNC | \ MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_PAGEPERTURB | MDBX_ACCEDE) #define ENV_CHANGELESS_FLAGS \ (MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \ MDBX_LIFORECLAIM | MDBX_EXCLUSIVE) #define ENV_USABLE_FLAGS (ENV_CHANGEABLE_FLAGS | ENV_CHANGELESS_FLAGS) #if !defined(__cplusplus) || CONSTEXPR_ENUM_FLAGS_OPERATIONS MDBX_MAYBE_UNUSED static void static_checks(void) { STATIC_ASSERT_MSG(INT16_MAX - CORE_DBS == MDBX_MAX_DBI, "Oops, MDBX_MAX_DBI or CORE_DBS?"); STATIC_ASSERT_MSG((unsigned)(MDBX_DB_ACCEDE | MDBX_CREATE) == ((DB_USABLE_FLAGS | DB_INTERNAL_FLAGS) & (ENV_USABLE_FLAGS | ENV_INTERNAL_FLAGS)), "Oops, some flags overlapped or wrong"); STATIC_ASSERT_MSG((ENV_INTERNAL_FLAGS & ENV_USABLE_FLAGS) == 0, "Oops, some flags overlapped or wrong"); } #endif /* Disabled for MSVC 19.0 (VisualStudio 2015) */ #ifdef __cplusplus } #endif #define MDBX_ASAN_POISON_MEMORY_REGION(addr, size) \ do { \ mdbx_trace("POISON_MEMORY_REGION(%p, %zu) at %u", (void *)(addr), \ (size_t)(size), __LINE__); \ ASAN_POISON_MEMORY_REGION(addr, size); \ } while (0) #define MDBX_ASAN_UNPOISON_MEMORY_REGION(addr, size) \ do { \ mdbx_trace("UNPOISON_MEMORY_REGION(%p, %zu) at %u", (void *)(addr), \ (size_t)(size), __LINE__); \ ASAN_UNPOISON_MEMORY_REGION(addr, size); \ } while (0)