mdb.tar.gz_Transaction_high_nosql

/** @file mdb.c * @brief memory-mapped database library * * A Btree-based database management library modeled loosely on the * BerkeleyDB API, but much simplified. */ /* * Copyright 2011-2013 Howard Chu, Symas Corp. * 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 btree.c written by Martin Hedenfalk. * * Copyright (c) 2009, 2010 Martin Hedenfalk <martin@bzero.se> * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #ifndef _GNU_SOURCE #define _GNU_SOURCE 1 #endif #include <sys/types.h> #include <sys/stat.h> #include <sys/param.h> #ifdef _WIN32 #include <windows.h> #else #include <sys/uio.h> #include <sys/mman.h> #ifdef HAVE_SYS_FILE_H #include <sys/file.h> #endif #include <fcntl.h> #endif #include <assert.h> #include <errno.h> #include <limits.h> #include <stddef.h> #include <inttypes.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h> #include <unistd.h> #if !(defined(BYTE_ORDER) || defined(__BYTE_ORDER)) #include <netinet/in.h> #include <resolv.h> /* defines BYTE_ORDER on HPUX and Solaris */ #endif #if defined(__APPLE__) || defined (BSD) # define MDB_USE_POSIX_SEM 1 # define MDB_FDATASYNC fsync #elif defined(ANDROID) # define MDB_FDATASYNC fsync #endif #ifndef _WIN32 #include <pthread.h> #ifdef MDB_USE_POSIX_SEM #include <semaphore.h> #endif #endif #ifdef USE_VALGRIND #include <valgrind/memcheck.h> #define VGMEMP_CREATE(h,r,z) VALGRIND_CREATE_MEMPOOL(h,r,z) #define VGMEMP_ALLOC(h,a,s) VALGRIND_MEMPOOL_ALLOC(h,a,s) #define VGMEMP_FREE(h,a) VALGRIND_MEMPOOL_FREE(h,a) #define VGMEMP_DESTROY(h) VALGRIND_DESTROY_MEMPOOL(h) #define VGMEMP_DEFINED(a,s) VALGRIND_MAKE_MEM_DEFINED(a,s) #else #define VGMEMP_CREATE(h,r,z) #define VGMEMP_ALLOC(h,a,s) #define VGMEMP_FREE(h,a) #define VGMEMP_DESTROY(h) #define VGMEMP_DEFINED(a,s) #endif #ifndef BYTE_ORDER # if (defined(_LITTLE_ENDIAN) || defined(_BIG_ENDIAN)) && !(defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)) /* Solaris just defines one or the other */ # define LITTLE_ENDIAN 1234 # define BIG_ENDIAN 4321 # ifdef _LITTLE_ENDIAN # define BYTE_ORDER LITTLE_ENDIAN # else # define BYTE_ORDER BIG_ENDIAN # endif # else # define BYTE_ORDER __BYTE_ORDER # endif #endif #ifndef LITTLE_ENDIAN #define LITTLE_ENDIAN __LITTLE_ENDIAN #endif #ifndef BIG_ENDIAN #define BIG_ENDIAN __BIG_ENDIAN #endif #if defined(__i386) || defined(__x86_64) || defined(_M_IX86) #define MISALIGNED_OK 1 #endif #include "lmdb.h" #include "midl.h" #if (BYTE_ORDER == LITTLE_ENDIAN) == (BYTE_ORDER == BIG_ENDIAN) # error "Unknown or unsupported endianness (BYTE_ORDER)" #elif (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF # error "Two's complement, reasonably sized integer types, please" #endif /** @defgroup internal MDB Internals * @{ */ /** @defgroup compat Windows Compatibility Macros * A bunch of macros to minimize the amount of platform-specific ifdefs * needed throughout the rest of the code. When the features this library * needs are similar enough to POSIX to be hidden in a one-or-two line * replacement, this macro approach is used. * @{ */ #ifdef _WIN32 #define MDB_PIDLOCK 0 #define pthread_t DWORD #define pthread_mutex_t HANDLE #define pthread_key_t DWORD #define pthread_self() GetCurrentThreadId() #define pthread_key_create(x,y) \ ((*(x) = TlsAlloc()) == TLS_OUT_OF_INDEXES ? ErrCode() : 0) #define pthread_key_delete(x) TlsFree(x) #define pthread_getspecific(x) TlsGetValue(x) #define pthread_setspecific(x,y) (TlsSetValue(x,y) ? 0 : ErrCode()) #define pthread_mutex_unlock(x) ReleaseMutex(x) #define pthread_mutex_lock(x) WaitForSingleObject(x, INFINITE) #define LOCK_MUTEX_R(env) pthread_mutex_lock((env)->me_rmutex) #define UNLOCK_MUTEX_R(env) pthread_mutex_unlock((env)->me_rmutex) #define LOCK_MUTEX_W(env) pthread_mutex_lock((env)->me_wmutex) #define UNLOCK_MUTEX_W(env) pthread_mutex_unlock((env)->me_wmutex) #define getpid() GetCurrentProcessId() #define MDB_FDATASYNC(fd) (!FlushFileBuffers(fd)) #define MDB_MSYNC(addr,len,flags) (!FlushViewOfFile(addr,len)) #define ErrCode() GetLastError() #define GET_PAGESIZE(x) {SYSTEM_INFO si; GetSystemInfo(&si); (x) = si.dwPageSize;} #define close(fd) (CloseHandle(fd) ? 0 : -1) #define munmap(ptr,len) UnmapViewOfFile(ptr) #ifdef PROCESS_QUERY_LIMITED_INFORMATION #define MDB_PROCESS_QUERY_LIMITED_INFORMATION PROCESS_QUERY_LIMITED_INFORMATION #else #define MDB_PROCESS_QUERY_LIMITED_INFORMATION 0x1000 #endif #define Z "I" #else #define Z "z" /** For MDB_LOCK_FORMAT: True if readers take a pid lock in the lockfile */ #define MDB_PIDLOCK 1 #ifdef MDB_USE_POSIX_SEM #define LOCK_MUTEX_R(env) mdb_sem_wait((env)->me_rmutex) #define UNLOCK_MUTEX_R(env) sem_post((env)->me_rmutex) #define LOCK_MUTEX_W(env) mdb_sem_wait((env)->me_wmutex) #define UNLOCK_MUTEX_W(env) sem_post((env)->me_wmutex) static int mdb_sem_wait(sem_t *sem) { int rc; while ((rc = sem_wait(sem)) && (rc = errno) == EINTR) ; return rc; } #else /** Lock the reader mutex. */ #define LOCK_MUTEX_R(env) pthread_mutex_lock(&(env)->me_txns->mti_mutex) /** Unlock the reader mutex. */ #define UNLOCK_MUTEX_R(env) pthread_mutex_unlock(&(env)->me_txns->mti_mutex) /** Lock the writer mutex. * Only a single write transaction is allowed at a time. Other writers * will block waiting for this mutex. */ #define LOCK_MUTEX_W(env) pthread_mutex_lock(&(env)->me_txns->mti_wmutex) /** Unlock the writer mutex. */ #define UNLOCK_MUTEX_W(env) pthread_mutex_unlock(&(env)->me_txns->mti_wmutex) #endif /* MDB_USE_POSIX_SEM */ /** Get the error code for the last failed system function. */ #define ErrCode() errno /** An abstraction for a file handle. * On POSIX systems file handles are small integers. On Windows * they're opaque pointers. */ #define HANDLE int /** A value for an invalid file handle. * Mainly used to initialize file variables and signify that they are * unused. */ #define INVALID_HANDLE_VALUE (-1) /** 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. */ #define GET_PAGESIZE(x) ((x) = sysconf(_SC_PAGE_SIZE)) #endif #if defined(_WIN32) || defined(MDB_USE_POSIX_SEM) #define MNAME_LEN 32 #else #define MNAME_LEN (sizeof(pthread_mutex_t)) #endif /** @} */ #ifndef _WIN32 /** A flag for opening a file and requesting synchronous data writes. * This is only used when writing a meta page. It's not strictly needed; * we could just do a normal write and then immediately perform a flush. * But if this flag is available it saves us an extra system call. * * @note If O_DSYNC is undefined but exists in /usr/include, * preferably set some compiler flag to get the definition. * Otherwise compile with the less efficient -DMDB_DSYNC=O_SYNC. */ #ifndef MDB_DSYNC # define MDB_DSYNC O_DSYNC #endif #endif /** Function for flushing the data of a file. Define this to fsync * if fdatasync() is not supporte